In riparian forests,litter decay provides essential energy and nutrients for both terrestrial and fluvial ecosystems.Litter mixing effects(LMEs)are crucial in regulating litter decay and nutrient dynamics,yet how LMEs...In riparian forests,litter decay provides essential energy and nutrients for both terrestrial and fluvial ecosystems.Litter mixing effects(LMEs)are crucial in regulating litter decay and nutrient dynamics,yet how LMEs change over time is unclear in riparian forests.In this study,leaf litter of three common species(Alnus sibirica Fisch.ex Turcz,Betula platyphylla Sukaczev,and Betula fruticosa Pall.)were mixed in an equal mass ratio and LMEs were measured for mass and nitrogen(N)remaining in whole litter mixtures over a 3-year period in a boreal riparian forest,northeastern China.LMEs were also assessed for component litter mass and N remaining by separating litter mixtures by species.During the decay of litter mixtures,antagonistic effects on mass and N remaining were dominant after one and two years of decay,whereas only additive effects were observed after three years.LMEs correlated negatively with functional diversity after the first and two years of decay but disappeared after three years.When sorting litter mixtures by species,non-additive LMEs on mass and N remaining decreased over incubation time.Moreover,non-additive LMEs were more frequent for litter of both B.platyphylla and B.fruticosa with lower N concentration than for A.sibirica litter with higher N concentration.These results indicate that incubation time is a key determinant of litter mixing effects during decay and highlight that late-stage litter mixture decay may be predicted from single litter decay dynamics in boreal riparian forests.展开更多
The development of electrocatalysts for the oxygen reduction reaction(ORR) that bears high selectivity,exceptional activity,and long-term stability is crucial for advancing various green energy technologies.Intermetal...The development of electrocatalysts for the oxygen reduction reaction(ORR) that bears high selectivity,exceptional activity,and long-term stability is crucial for advancing various green energy technologies.Intermetallics composed of platinum and transition metals are considered to be promising candidates for this purpose.However,they typically face challenges such as unfavorable intrinsic activity and a propensity for particle aggregation,diminishing their ORR performance.Against this backdrop,we present our findings on a N-doped carbon confined Pt_(3)Co intermetallic doped with p-block metal tin(Pt_(3)Co_(x)Sn_(1-x)/NC).The introduction of Sn induces lattice strain due to its larger atomic size,which leads to the distortion of the Pt_(3)Co lattice structure,while the coupling of carbon polyhedra inhibits the particle aggregation.The optimized Pt_(3)Co_(0.8)Sn_(0.2)/NC catalyst demonstrates an impressive half-wave potential of 0.86 V versus RHE,surpassing both Pt_(3)Co/NC and Pt_(3)Sn/NC catalysts.Moreover,the Pt_(3)Co_(0.8)Sn_(0.2)/NC exhibits a mass-specific activity as high as 1.4 A mg_(Pt)^(-1),ranking it in the top level among the intermetallicsbased ORR electrocatalysts.When further employed as a cathode material in a self-assembled zinc-air battery,it shows stable operation for over 80 h.These results underscore the significant impact of lattice strain engineering through the strategic doping of p-block metal in the carbon-confined Pt_(3)Co intermetallic,thereby enhancing the catalytic efficiency for the ORR.展开更多
BACKGROUND Presently,there is no established standard anti-blood clot therapy for patients facing acute myocardial infarction(AMI)complicated by left ventricular thrombus(LVT).While vitamin K antagonists are the prefe...BACKGROUND Presently,there is no established standard anti-blood clot therapy for patients facing acute myocardial infarction(AMI)complicated by left ventricular thrombus(LVT).While vitamin K antagonists are the preferred choice for oral blood thinning,determining the best course of blood-thinning medication remains challenging.It is unclear if non-vitamin K antagonist oral blood thinners have different effectiveness in treating LVT.This study significantly contributes to the medical community.CASE SUMMARY The blood-thinning treatment of a patient with AMI and LVT was analyzed.Triple blood-thinning therapy included daily enteric-coated aspirin tablets at 0.1 g,daily clopidogrel hydrogen sulfate at 75 mg,and dabigatran etexilate at 110 mg twice daily.After 15 d,the patient’s LVT did not decrease but instead increased.Clinical pharmacists comprehensively analyzed the cases from the perspective of the patient’s disease status and drug interaction.The drug regimen was reformulated for the patient,replacing dabigatran etexilate with warfarin,and was administered for six months.The clinical pharmacist provided the patient with professional and standardized pharmaceutical services.The patient’s condition was discharged after meeting the international normalized ratio value(2-3)criteria.The patient fully complied with the follow-up,and the time in the therapeutic range was 78.57%,with no serious adverse effects during pharmaceutical monitoring.CONCLUSION Warfarin proves to be an effective drug for patients with AMI complicated by LVT,and its blood-thinning course lasts for six months.展开更多
[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were ...[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were obtained in Escherichia coli prokaryotic expression system by optimizing codons and expression conditions of E.coli.Furthermore,based on the purified soluble N protein and NH fusion protein,a high-sensitivity fluorescence immunoassay kit for detecting the antibody against PPR V was established.[Results]The method could quickly and quantitatively detect PPR V antibody in sheep serum,with high sensitivity and specificity,without any cross reaction to other related sheep pathogens.The intra-batch and inter-batch coefficients of variation were less than 10%and 15%,respectively,and the method had good repeatability.Through detection on 292 clinical serum samples,it was compared with the French IDVET competitive ELISA kit,and the coincidence rate of the two methods reached 93.84%.Compared with the serum neutralization test,the detected titer value of the high-sensitivity rapid fluorescence quantitative detection method was basically consistent with the tilter value obtained by the neutralization test on the standard positive serum(provided by the WOAH Brucellosis Reference Laboratory of France).[Conclusions]This method can realize rapid quantitative detection of PPR V antibody on site,and has high practical value and popularization value.展开更多
Objective: To discuss the changes in the tight junction protein of intestinal epithelium and permeability of colonic mucosa and its possible mechanism by building the rat mode of inflammatory bowel disease at the chro...Objective: To discuss the changes in the tight junction protein of intestinal epithelium and permeability of colonic mucosa and its possible mechanism by building the rat mode of inflammatory bowel disease at the chronic recovery stage. Methods: A total of 36 SD rats were divided into the model group and control one according to the random number table, with 18 rats in each group. Rats in the model group were given the 3% dextran sulfate sodium solution by the way of drinking for 7 d to build the rat model of inflammatory bowel disease, while rats in the control group were given free drinking of water. Six rats were executed at day 7, 14 and 21 respectively. The colonic tissues were collected from rats to observe the pathological changes of colonic mucosa. The activity of myeloperoxidase was detected and the white blood count was performed for rats in each group. The Ussing chamber technique was employed to detect the transepithelial electrical resistance(TER) and short-circuit current(SC) of colonic mucosa of rats in different time intervals; the quantum dots labeling technique was employed to detect the expression level of claudin-1 and claudin-2 in the colonic tissues. Results: After the successful modeling, the weight of rats in the model group was significantly reduced, while the disease activity index score was increased. The weight was at the lowest level at day 14 and then it began to increase afterwards. The disease activity index score was at the highest level at day 12 and then it began to decrease gradually. The activity of myeloperoxidase and WBC for rats in the model group all reached the peak value at day 14 and then decreased gradually. There was no significant difference in the changes of TER and SC in different time intervals for rats in the control group(P>0.05). TER of model group was at the lowest level at day 14 and then increased gradually; SC was at the highest level at day 14 and then decreased gradually. TER of model group at day 7, 14 and 21 was significantly lower than that of control group, while SC of model group was significantly higher than that of control group(P<0.05). There was no significant difference in the change of mean fluorescence intensity of claudin-1 and claudin-2 in different time intervals for rats in the control group(P>0.05). The claudin-1 and claudin-2 for rats in the model group reached the highest level at day 14 and then decreased gradually. The claudin-1 and claudin-2 of model group at day 7, 14 and 21 was significantly higher than that of control group(P<0.05). Conclusions: After the acute stage, the inflammatory bowel disease is then in the chronic recovery stage; the increased permeability of colonic mucosa and increased expression of tight junction protein of intestinal epithelium are closely related to the pathogenesis and development of disease. The tight junction protein plays a key role in the pathogenesis of injured colonic barrier of inflammatory bowel disease.展开更多
The hydrocarbon generation effectiveness of lacustrine limestone has been gradually proven. The Da'anzhai Member limestone is the most important Jurassic oil-producing layer in the central Sichuan Basin, and the c...The hydrocarbon generation effectiveness of lacustrine limestone has been gradually proven. The Da'anzhai Member limestone is the most important Jurassic oil-producing layer in the central Sichuan Basin, and the characteristics of limestone organic matter are often overlooked. 175 typical samples of different lithologies from 19 wells were systematically analyzed to determine hydrocarbon generation, controlling factors and formation models by analyses of organic matter, minerals, elements, isotopes and petrography. (1) Lacustrine paleoenvironments can be beneficial for the enrichment of organic matter in limestone. A favorable environment would be a quiet, low-energy zone in a warm and humid climate with an appropriate supply of terrestrial inputs. (2) Lacustrine limestone has a higher organic matter conversion rate, and a lower hydrocarbon generation threshold than argillaceous source rocks, and can be effective source rock. (3) The mud-bearing shell limestone from the forebeach to the lake slope is thick, with a relatively high abundance of organic matter, and its hydrocarbon generation is effective. This study can clarify the effectiveness and enrichment of the limestone organic matters in the study area, and contribute to an understanding of hydrocarbon generation for full-rock system in a lacustrine mixed sedimentary environment.展开更多
Micro-grinding with a spherical grinding head has been deemed an indispensable method in high-risk surgeries, such as neurosurgery and spine surgery, where bone grinding has long been plagued by the technical bottlene...Micro-grinding with a spherical grinding head has been deemed an indispensable method in high-risk surgeries, such as neurosurgery and spine surgery, where bone grinding has long been plagued by the technical bottleneck of mechanical stress-induced crack damage. In response to this challenge, the ultrasound-assisted biological bone micro-grinding novel process with a spherical grinding head has been proposed by researchers. Force modeling is a prerequisite for process parameter determination in orthopedic surgery, and the difculty in establishing and accurately predicting bone micro-grinding force prediction models is due to the geometric distribution of abrasive grains and the dynamic changes in geometry and kinematics during the cutting process. In addressing these critical needs and technical problems, the shape and protrusion heights of the wear particle of the spherical grinding head were frst studied, and the gradual rule of the contact arc length under the action of high-speed rotating ultrasonic vibration was proposed. Second, the mathematical model of the maximum thickness of undeformed chips under ultrasonic vibration of the spherical grinding head was established. Results showed that ultrasonic vibration can reduce the maximum thickness of undeformed chips and increase the range of ductile and bone meal removals, revealing the mechanism of reducing grinding force. Further, the dynamic grinding behavior of diferent layers of abrasive particles under diferent instantaneous interaction states was studied. Finally, a prediction model of micro-grinding force was established in accordance with the relationship between grinding force and cutting depth, revealing the mechanism of micro-grinding force transfer under ultrasonic vibration. The theoretical model’s average deviations are 10.37% in x-axis direction, 6.85% in y-axis direction, and 7.81% in z-axis direction compared with the experimental results. This study provides theoretical guidance and technical support for clinical bone micro-grinding.展开更多
As“Bohai Red”scallops were originated from the hybrids between the Peruvian scallop(Argopecten purpuratus)and the bay scallop(Argopecten irradians)northern subspecies(Argopecten irradians irradians).Twelve Wnt membe...As“Bohai Red”scallops were originated from the hybrids between the Peruvian scallop(Argopecten purpuratus)and the bay scallop(Argopecten irradians)northern subspecies(Argopecten irradians irradians).Twelve Wnt members were identified from the two subspecies of bay scallop,and 13 Wnt genes were found in the genome of the Peruvian scallop.Protein structure analyses showed that most Wnt genes poses all 5 conserved motifs except Wnt1,Wnt2,Wnt6,and Wnt9 in the bay scallops and Wnt2 and Wnt9 in the Peruvian scallop.Unexpectedly,Wnt8 gene was present while Wnt3 was absent in both the bay scallops and the Peruvian scallop.Phylogenetic analysis revealed that Wnt3 might have disappeared in the early evolution of mollusks.The expression profile of Wnt genes in the“Bohai Red”exposed to different temperatures was examined by qRT-PCR.Results show that expression of Wnt genes responded differentially to temperature changes.The Wnt genes such as Wnt1,Wnt6,Wnt7,Wnt11,and WntA that responded slowly to low and high temperature stresses may be related to the maintenance of basic homeostasis.Other Wnt genes such as Wnt4,Wnt9,Wnt5,and Wnt2 that responded rapidly to low temperature may play an important role in organismal protection against low temperature stress.And yet some Wnt genes including Wnt10,Wnt16,and Wnt8 that responded quickly to high temperature stress may play key roles in response to high temperature stress.The results provide new insights into the evolution and function of Wnt genes in bivalves and eventually benefit culture of“Bohai Red”scallops.展开更多
Following the outbreak of coronavirus disease 2019(COVID-19),several severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-related coronaviruses have been discovered.Previous research has identified a novel line...Following the outbreak of coronavirus disease 2019(COVID-19),several severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-related coronaviruses have been discovered.Previous research has identified a novel lineage of SARS-CoV-2-related CoVs in bats,including RsYN04,which recognizes human angiotensin-converting enzyme 2(ACE2)and thus poses a potential threat to humans.Here,we screened the binding of the RsYN04receptor-binding domain(RBD)to ACE2 orthologs from 52animal species and found that the virus showed a narrower ACE2-binding spectrum than SARS-CoV-2.However,the presence of the T484W mutation in the RsYN04 RBD broadened its range.We also evaluated 44 SARS-CoV-2antibodies targeting seven epitope communities in the SARS-CoV-2 RBD,together with serum obtained from COVID-19 convalescents and vaccinees,to determine their cross-reaction against RsYN04.Results showed that no antibodies,except for the RBD-6 and RBD-7 classes,bound to the RsYN04 RBD,indicating substantial immune differences from SARS-CoV-2.Furthermore,the structure of the RsYN04 RBD in complex with cross-reactive antibody S43 in RBD-7 revealed a potently broad epitope for the development of therapeutics and vaccines.Our findings suggest RsYN04 and other viruses belonging to the same clade have the potential to infect several species,including humans,highlighting the necessity for viral surveillance and development of broad anticoronavirus countermeasures.展开更多
Kernel adaptive filters(KAFs)have sparked substantial attraction for online non-linear learning applications.It is noted that the effectiveness of KAFs is highly reliant on a rational learning criterion.Concerning thi...Kernel adaptive filters(KAFs)have sparked substantial attraction for online non-linear learning applications.It is noted that the effectiveness of KAFs is highly reliant on a rational learning criterion.Concerning this,the logarithmic hyperbolic cosine(lncosh)criterion with better robustness and convergence has drawn attention in recent studies.However,existing lncosh loss-based KAFs use the stochastic gradient descent(SGD)for optimization,which lack a trade-off between the convergence speed and accuracy.But recursion-based KAFs can provide more effective filtering performance.Therefore,a Nyström method-based robust sparse kernel recursive least lncosh loss algorithm is derived in this article.Experiments via measures and synthetic data against the non-Gaussian noise confirm the superiority with regard to the robustness,accuracy performance,and computational cost.展开更多
Nowadays,the rapid development of edge computing has driven an increasing number of deep learning applications deployed at the edge of the network,such as pedestrian and vehicle detection,to provide efficient intellig...Nowadays,the rapid development of edge computing has driven an increasing number of deep learning applications deployed at the edge of the network,such as pedestrian and vehicle detection,to provide efficient intelligent services to mobile users.However,as the accuracy requirements continue to increase,the components of deep learning models for pedestrian and vehicle detection,such as YOLOv4,become more sophisticated and the computing resources required for model training are increasing dramatically,which in turn leads to significant challenges in achieving effective deployment on resource-constrained edge devices while ensuring the high accuracy performance.For addressing this challenge,a cloud-edge collaboration-based pedestrian and vehicle detection framework is proposed in this paper,which enables sufficient training of models by utilizing the abundant computing resources in the cloud,and then deploying the well-trained models on edge devices,thus reducing the computing resource requirements for model training on edge devices.Furthermore,to reduce the size of the model deployed on edge devices,an automatic pruning method combines the convolution layer and BN layer is proposed to compress the pedestrian and vehicle detection model size.Experimental results show that the framework proposed in this paper is able to deploy the pruned model on a real edge device,Jetson TX2,with 6.72 times higher FPS.Meanwhile,the channel pruning reduces the volume and the number of parameters to 96.77%for the model,and the computing amount is reduced to 81.37%.展开更多
Research of spin polarization of magnetic CoFeB thin films is of practical importance in spintronic applications.Here,using a direct characterization technique of spin-resolved photoemission spectroscopy,we obtain the...Research of spin polarization of magnetic CoFeB thin films is of practical importance in spintronic applications.Here,using a direct characterization technique of spin-resolved photoemission spectroscopy,we obtain the surface spin polarization of amorphous Co_(40)Fe_(40)B_(20)thin films with different annealing temperatures from 100℃to 500℃prepared by magnetron sputtering.After high annealing temperature,a quasi-semiconductor state is gradually formed at the CoFeB surface due to the boron diffusion.While the global magnetization remains almost constant,the secondary electrons’spin polarization,average valence band spin polarization and the spin polarization at Fermi level from spin-resolved photoemission spectroscopy show a general trend of decreasing with the increasing annealing temperature above 100℃.These distinct surface properties are attributed to the enhanced Fe-B bonding due to the boron segregation upon surface after annealing as confirmed by x-ray photoelectron spectroscopy and scanning transmission electron microscopy with energy dispersive spectroscopy.Our findings provide insight into the surface spin-resolved electronic structure of the CoFeB thin films,which should be important for development of high-performance magnetic random-access memories.展开更多
Climate models are vital for understanding and projecting global climate change and its associated impacts.However,these models suffer from biases that limit their accuracy in historical simulations and the trustworth...Climate models are vital for understanding and projecting global climate change and its associated impacts.However,these models suffer from biases that limit their accuracy in historical simulations and the trustworthiness of future projections.Addressing these challenges requires addressing internal variability,hindering the direct alignment between model simulations and observations,and thwarting conventional supervised learning methods.Here,we employ an unsupervised Cycle-consistent Generative Adversarial Network(CycleGAN),to correct daily Sea Surface Temperature(SST)simulations from the Community Earth System Model 2(CESM2).Our results reveal that the CycleGAN not only corrects climatological biases but also improves the simulation of major dynamic modes including the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole mode,as well as SST extremes.Notably,it substantially corrects climatological SST biases,decreasing the globally averaged Root-Mean-Square Error(RMSE)by 58%.Intriguingly,the CycleGAN effectively addresses the well-known excessive westward bias in ENSO SST anomalies,a common issue in climate models that traditional methods,like quantile mapping,struggle to rectify.Additionally,it substantially improves the simulation of SST extremes,raising the pattern correlation coefficient(PCC)from 0.56 to 0.88 and lowering the RMSE from 0.5 to 0.32.This enhancement is attributed to better representations of interannual,intraseasonal,and synoptic scales variabilities.Our study offers a novel approach to correct global SST simulations and underscores its effectiveness across different time scales and primary dynamical modes.展开更多
Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking.This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey so...Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking.This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey soils.To validate the feasibility and efficacy of the proposed approach,direct tensile tests were employed to determine the tensile strength of the compacted soil with different W-OH treatment concentrations and water contents.Desiccation tests were also performed to evaluate the effectiveness of W-OH treatment in enhancing soil tensile cracking resistance.During this period,the effects of W-OH treatment concentration and water content on tensile properties,soil suction and microstructure were investigated.The tensile tests reveal that W-OH treatment has a significant impact on the tensile strength and failure mode of the soil,which not only effectively enhances the tensile strength and failure displacement,but also changes the brittle failure behavior into a more ductile quasi-brittle failure behavior.The suction measurements and mercury intrusion porosimetry(MIP)tests show that W-OH treatment can slightly reduce soil suction by affecting skeleton structure and increasing macropores.Combined with the microstructural analysis,it becomes evident that the significant improvement in soil tensile behavior through W-OH treatment is mainly attributed to the W-OH gel's ability to provide additional binding force for bridging and encapsulating the soil particles.Moreover,desiccation tests demonstrate that W-OH treatment can significantly reduce or even inhibit the formation of soil tensile cracking.With the increase of W-OH treatment concentration,the surface crack ratio and total crack length are significantly reduced.This study enhances a fundamental understanding of eco-polymer impacts on soil mechanical properties and provides valuable insight into their potential application for improving soil crack resistance.展开更多
A submerged cavitation water jet(SCWJ)is an effective method to recycle solid propellant from obsolete solid engines by the breaking method.Solid propellant's breaking modes and mechanical process under SCWJ impac...A submerged cavitation water jet(SCWJ)is an effective method to recycle solid propellant from obsolete solid engines by the breaking method.Solid propellant's breaking modes and mechanical process under SCWJ impact are unclear.This study aims to understand those impact breaking mechanisms.The hydroxyl-terminated polybutadiene(HTPB)propellant was chosen as the research material,and a self-designed test system was used to conduct impact tests at four different working pressures.The high-speed camera characterized crack propagation,and the DIC method calculated strain change during the impact process.Besides,micro and macro fracture morphologies were characterized by scanning electron microscope(SEM)and computed tomography(CT)scanning.The results reveal that the compressive strain concentration region locates right below the nozzle,and the shear strain region distributes symmetrically with the jet axis,which increases to 4% at first 16th ms,the compressive strain rises to 2% and 6% in the axial and transverse direction,respectively.The two tensile cracks formed first at the compression strain concentrate region,and there generate many shear cracks around the tensile cracks,and those shear cracks that develop and aggregate cause the cracks to become wider and cut through the tensile cracks,forming the tensile-shear cracks and the impact parts eventually fail.The HTPB propellant forms a breaking hole shaped conical after impact 10 s.The mass loss increases by 17 times at maximum,with the working pressure increasing by three times.Meanwhile,the damage value of the breaking hole remaining on the surface increases by 7.8 times while 2.9 times in the depth of the breaking hole.The breaking efficiency is closely affected by working pressures.The failure modes of HTPB impacted by SCWJ are classified as tensile crack-dominated and tensile-shear crack-dominated damage mechanisms.展开更多
Mikania micrantha is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production.It has advantages in photosynthesis,includi...Mikania micrantha is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production.It has advantages in photosynthesis,including a similar net photosynthetic rate as C4 plants and a higher carbon fixation capacity.We used a combination of genomics and transcriptomics approaches to study the evolutionary mechanisms and circadian expression patterns of M.micrantha.In M.micrantha,16 positive selection genes focused on photoreaction and utilization of photoassimilates.In different tissues,98.1%of the genes associated with photoresponse had high expression in stems,and more than half of the genes of the C4 cycle had higher expression in stems than in leaves.In stomatal opening and closing,2 genes of carbonic anhydrase(CAs)had higher expression at 18:00 than at 8:00,and the slow anion channel 1(SLAC1)and high-leaf-temperature 1 kinase(HT1)genes were expressed at low levels at 18:00.In addition,genes associated with photosynthesis had higher expression levels at 7:00 and 17:00.We hypothesized that M.micrantha may undergo photosynthesis in the stem and flower organs and that some stomata of the leaves were opening at night by CO_(2)signals.In addition,its evolution may attenuate photoinhibition at high light intensities,and enhance more efficient of photosynthesis during low light intensity.And the tissue-specific photosynthetic types and different diurnal pattern of photosynthetic-related genes may contribute to its rapid colonization of new habitats of M.micrantha.展开更多
The proper recycling of spent lithium-ion batteries(LIBs)can promote the recovery and utilization of valuable resources,while also negative environmental effects resulting from the presence of toxic and hazardous subs...The proper recycling of spent lithium-ion batteries(LIBs)can promote the recovery and utilization of valuable resources,while also negative environmental effects resulting from the presence of toxic and hazardous substances.In this study,a new environmentally friendly hydro-metallurgical process was proposed for leaching lithium(Li),nickel(Ni),cobalt(Co),and manganese(Mn)from spent LIBs using sulfuric acid with citric acid as a reductant.The effects of the concentration of sulfuric acid,the leaching temperature,the leaching time,the solid-liquid ratio,and the reducing agent dosage on the leaching behavior of the above elements were investigated.Key parameters were optimized using response surface methodology(RSM)to maximize the recovery of metals from spent LIBs.The maxim-um recovery efficiencies of Li,Ni,Co,and Mn can reach 99.08%,98.76%,98.33%,and 97.63%.under the optimized conditions(the sulfuric acid concentration was 1.16 mol/L,the citric acid dosage was 15wt%,the solid-liquid ratio was 40 g/L,and the temperature was 83℃ for 120 min),respectively.It was found that in the collaborative leaching process of sulfuric acid and citric acid,the citric acid initially provided strong reducing CO_(2)^(-),and the transition metal ions in the high state underwent a reduction reaction to produce transition metal ions in the low state.Additionally,citric acid can also act as a proton donor and chelate with lower-priced transition metal ions,thus speeding up the dissolution process.展开更多
The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three...The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch mode.The kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn coil.The full magnetic field strength was 0.005 T.This paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker magnets.The relevant experimental results are also presented.The pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 MHz.The developed kicker satisfies the requirements for the SHINE project.Finally,numerous recommendations for the future optimization of kicker magnets are provided.展开更多
Traditional selection of combustion catalysis is time-consuming and labor-intensive.Theoretical calculation is expected to resolve this problem.The adsorption energy of HMX and O atoms on 13 metal oxides was calculate...Traditional selection of combustion catalysis is time-consuming and labor-intensive.Theoretical calculation is expected to resolve this problem.The adsorption energy of HMX and O atoms on 13 metal oxides was calculated using DMol3,since HMX and O are key substances in decomposition process.And the relationship between the adsorption energy of HMX,O on metal oxides(TiO_(2),Al_(2)O_(3),PbO,CuO,Fe_(2)O_(3),Co_(3)O_(4),Bi_(2)O_(3),NiO)and experimental T30 values(time required for the decomposition depth of HMX to reach 30%)was depicted as volcano plot.Thus,the T30 values of other metal oxides was predicted based on their adsorption energy on volcano plot and validated by previous experimental data.Further,the adsorption energy of HMX on ZrO_(2)and MnO_(2)was predicted based on the linear relationship between surface energy and adsorption energy,and T30 values were estimated based on volcano plot.The apparent activation energy data of HMX/MgO,HMX/SnO_(2),HMX/ZrO_(2),and HMX/MnO_(2)obtained from DSC experiments are basically consistent with our predicted T30 values,indicating that it is feasible to predict the catalytic activity based on the adsorption calculation,and it is expected that these simple structural properties can predict adsorption energy to reduce the large quantities of computation and experiment cost.展开更多
Reactive transport modeling(RTM)is an emerging method used to address geological issues in diagenesis research.However,the extrapolation of RTM results to practical reservoir prediction is not sufficiently understood....Reactive transport modeling(RTM)is an emerging method used to address geological issues in diagenesis research.However,the extrapolation of RTM results to practical reservoir prediction is not sufficiently understood.This paper presents a case study of the Eocene Qaidam Basin that combines RTM results with petrological and mineralogical evidence.The results show that the Eocene Xiaganchaigou Formation is characterized by mixed siliciclastic-carbonate-evaporite sedimentation in a semiclosed saline lacustrine environment.Periodic evaporation and salinization processes during the syngeneticpenecontemporaneous stage gave rise to the replacive genesis of dolomites and the cyclic enrichment of dolomite in the middle-upper parts of the meter-scale depositional sequences.The successive change in mineral paragenesis from terrigenous clastics to carbonates to evaporites was reconstructed using RTM simulations.Parametric uncertainty analyses further suggest that the evaporation intensity(brine salinity)and particle size of sediments(reactive surface area)were important rate-determining factors in the dolomitization,as shown by the relatively higher reaction rates under conditions of higher brine salinity and fine-grained sediments.Combining the simulation results with measured mineralogical and reservoir physical property data indicates that the preservation of original intergranular pores and the generation of porosity via replacive dolomitization were the major formation mechanisms of the distinctive lacustrine dolomite reservoirs(widespread submicron intercrystalline micropores)in the Eocene Qaidam Basin.The results confirm that RTM can be effectively used in geological studies,can provide a better general understanding of the dolomitizing fluid-rock interactions,and can shed light on the spatiotemporal evolution of mineralogy and porosity during dolomitization and the formation of lacustrine dolomite reservoirs.展开更多
基金National Natural Science Foundation of China(41771108 and 31570479)the Natural Science Foundation of Jiangxi,China(20212ACB215002
文摘In riparian forests,litter decay provides essential energy and nutrients for both terrestrial and fluvial ecosystems.Litter mixing effects(LMEs)are crucial in regulating litter decay and nutrient dynamics,yet how LMEs change over time is unclear in riparian forests.In this study,leaf litter of three common species(Alnus sibirica Fisch.ex Turcz,Betula platyphylla Sukaczev,and Betula fruticosa Pall.)were mixed in an equal mass ratio and LMEs were measured for mass and nitrogen(N)remaining in whole litter mixtures over a 3-year period in a boreal riparian forest,northeastern China.LMEs were also assessed for component litter mass and N remaining by separating litter mixtures by species.During the decay of litter mixtures,antagonistic effects on mass and N remaining were dominant after one and two years of decay,whereas only additive effects were observed after three years.LMEs correlated negatively with functional diversity after the first and two years of decay but disappeared after three years.When sorting litter mixtures by species,non-additive LMEs on mass and N remaining decreased over incubation time.Moreover,non-additive LMEs were more frequent for litter of both B.platyphylla and B.fruticosa with lower N concentration than for A.sibirica litter with higher N concentration.These results indicate that incubation time is a key determinant of litter mixing effects during decay and highlight that late-stage litter mixture decay may be predicted from single litter decay dynamics in boreal riparian forests.
基金Natural Science Foundation of Jiangsu Province (BK20210735)National Natural Science Foundation of China (52201269, 52302296)+4 种基金Collaborative Innovation Center of Suzhou Nano Science and Technologythe 111 Projectthe Suzhou Key Laboratory of Functional Nano and Soft MaterialsJiangsu Key Laboratory for Carbon-Based Functional Materials & Devicesthe funding from the Gusu leading talent plan for scientific and technological innovation and entrepreneurship (ZXL2022487)。
文摘The development of electrocatalysts for the oxygen reduction reaction(ORR) that bears high selectivity,exceptional activity,and long-term stability is crucial for advancing various green energy technologies.Intermetallics composed of platinum and transition metals are considered to be promising candidates for this purpose.However,they typically face challenges such as unfavorable intrinsic activity and a propensity for particle aggregation,diminishing their ORR performance.Against this backdrop,we present our findings on a N-doped carbon confined Pt_(3)Co intermetallic doped with p-block metal tin(Pt_(3)Co_(x)Sn_(1-x)/NC).The introduction of Sn induces lattice strain due to its larger atomic size,which leads to the distortion of the Pt_(3)Co lattice structure,while the coupling of carbon polyhedra inhibits the particle aggregation.The optimized Pt_(3)Co_(0.8)Sn_(0.2)/NC catalyst demonstrates an impressive half-wave potential of 0.86 V versus RHE,surpassing both Pt_(3)Co/NC and Pt_(3)Sn/NC catalysts.Moreover,the Pt_(3)Co_(0.8)Sn_(0.2)/NC exhibits a mass-specific activity as high as 1.4 A mg_(Pt)^(-1),ranking it in the top level among the intermetallicsbased ORR electrocatalysts.When further employed as a cathode material in a self-assembled zinc-air battery,it shows stable operation for over 80 h.These results underscore the significant impact of lattice strain engineering through the strategic doping of p-block metal in the carbon-confined Pt_(3)Co intermetallic,thereby enhancing the catalytic efficiency for the ORR.
文摘BACKGROUND Presently,there is no established standard anti-blood clot therapy for patients facing acute myocardial infarction(AMI)complicated by left ventricular thrombus(LVT).While vitamin K antagonists are the preferred choice for oral blood thinning,determining the best course of blood-thinning medication remains challenging.It is unclear if non-vitamin K antagonist oral blood thinners have different effectiveness in treating LVT.This study significantly contributes to the medical community.CASE SUMMARY The blood-thinning treatment of a patient with AMI and LVT was analyzed.Triple blood-thinning therapy included daily enteric-coated aspirin tablets at 0.1 g,daily clopidogrel hydrogen sulfate at 75 mg,and dabigatran etexilate at 110 mg twice daily.After 15 d,the patient’s LVT did not decrease but instead increased.Clinical pharmacists comprehensively analyzed the cases from the perspective of the patient’s disease status and drug interaction.The drug regimen was reformulated for the patient,replacing dabigatran etexilate with warfarin,and was administered for six months.The clinical pharmacist provided the patient with professional and standardized pharmaceutical services.The patient’s condition was discharged after meeting the international normalized ratio value(2-3)criteria.The patient fully complied with the follow-up,and the time in the therapeutic range was 78.57%,with no serious adverse effects during pharmaceutical monitoring.CONCLUSION Warfarin proves to be an effective drug for patients with AMI complicated by LVT,and its blood-thinning course lasts for six months.
基金Supported by The National Project for the Prevention and Control of Major Exotic Animal Diseases(2022YFD1800500)National Mutton Sheep Industrial Technology System(CARS39).
文摘[Objectives]This study was conducted to establish a rapid quantitative method for detecting antibody against Peste des Petits Ruminants Virus(PPR V)in sheep serum.[Methods]Soluble N protein and NH fusion protein were obtained in Escherichia coli prokaryotic expression system by optimizing codons and expression conditions of E.coli.Furthermore,based on the purified soluble N protein and NH fusion protein,a high-sensitivity fluorescence immunoassay kit for detecting the antibody against PPR V was established.[Results]The method could quickly and quantitatively detect PPR V antibody in sheep serum,with high sensitivity and specificity,without any cross reaction to other related sheep pathogens.The intra-batch and inter-batch coefficients of variation were less than 10%and 15%,respectively,and the method had good repeatability.Through detection on 292 clinical serum samples,it was compared with the French IDVET competitive ELISA kit,and the coincidence rate of the two methods reached 93.84%.Compared with the serum neutralization test,the detected titer value of the high-sensitivity rapid fluorescence quantitative detection method was basically consistent with the tilter value obtained by the neutralization test on the standard positive serum(provided by the WOAH Brucellosis Reference Laboratory of France).[Conclusions]This method can realize rapid quantitative detection of PPR V antibody on site,and has high practical value and popularization value.
基金supported by Project of Science and Technology Development of Hubei Province(No.2013HBF21825)
文摘Objective: To discuss the changes in the tight junction protein of intestinal epithelium and permeability of colonic mucosa and its possible mechanism by building the rat mode of inflammatory bowel disease at the chronic recovery stage. Methods: A total of 36 SD rats were divided into the model group and control one according to the random number table, with 18 rats in each group. Rats in the model group were given the 3% dextran sulfate sodium solution by the way of drinking for 7 d to build the rat model of inflammatory bowel disease, while rats in the control group were given free drinking of water. Six rats were executed at day 7, 14 and 21 respectively. The colonic tissues were collected from rats to observe the pathological changes of colonic mucosa. The activity of myeloperoxidase was detected and the white blood count was performed for rats in each group. The Ussing chamber technique was employed to detect the transepithelial electrical resistance(TER) and short-circuit current(SC) of colonic mucosa of rats in different time intervals; the quantum dots labeling technique was employed to detect the expression level of claudin-1 and claudin-2 in the colonic tissues. Results: After the successful modeling, the weight of rats in the model group was significantly reduced, while the disease activity index score was increased. The weight was at the lowest level at day 14 and then it began to increase afterwards. The disease activity index score was at the highest level at day 12 and then it began to decrease gradually. The activity of myeloperoxidase and WBC for rats in the model group all reached the peak value at day 14 and then decreased gradually. There was no significant difference in the changes of TER and SC in different time intervals for rats in the control group(P>0.05). TER of model group was at the lowest level at day 14 and then increased gradually; SC was at the highest level at day 14 and then decreased gradually. TER of model group at day 7, 14 and 21 was significantly lower than that of control group, while SC of model group was significantly higher than that of control group(P<0.05). There was no significant difference in the change of mean fluorescence intensity of claudin-1 and claudin-2 in different time intervals for rats in the control group(P>0.05). The claudin-1 and claudin-2 for rats in the model group reached the highest level at day 14 and then decreased gradually. The claudin-1 and claudin-2 of model group at day 7, 14 and 21 was significantly higher than that of control group(P<0.05). Conclusions: After the acute stage, the inflammatory bowel disease is then in the chronic recovery stage; the increased permeability of colonic mucosa and increased expression of tight junction protein of intestinal epithelium are closely related to the pathogenesis and development of disease. The tight junction protein plays a key role in the pathogenesis of injured colonic barrier of inflammatory bowel disease.
基金supported by the National Natural Science Foundation of China(Grants 41902131 and 41821002 and 4169130014).
文摘The hydrocarbon generation effectiveness of lacustrine limestone has been gradually proven. The Da'anzhai Member limestone is the most important Jurassic oil-producing layer in the central Sichuan Basin, and the characteristics of limestone organic matter are often overlooked. 175 typical samples of different lithologies from 19 wells were systematically analyzed to determine hydrocarbon generation, controlling factors and formation models by analyses of organic matter, minerals, elements, isotopes and petrography. (1) Lacustrine paleoenvironments can be beneficial for the enrichment of organic matter in limestone. A favorable environment would be a quiet, low-energy zone in a warm and humid climate with an appropriate supply of terrestrial inputs. (2) Lacustrine limestone has a higher organic matter conversion rate, and a lower hydrocarbon generation threshold than argillaceous source rocks, and can be effective source rock. (3) The mud-bearing shell limestone from the forebeach to the lake slope is thick, with a relatively high abundance of organic matter, and its hydrocarbon generation is effective. This study can clarify the effectiveness and enrichment of the limestone organic matters in the study area, and contribute to an understanding of hydrocarbon generation for full-rock system in a lacustrine mixed sedimentary environment.
基金Supported by National Natural Science Foundation of China(Grant Nos.51975305,52105457,and 52205481)the Special Fund of Taishan Scholars Project(Grant No.tsqn202211179)+1 种基金Shandong Provincial Youth Talent Promotion Project(Grant No.SDAST2021qt12)Shandong Provincial Natural Science Foundation(Grant Nos.ZR2023QE057,ZR2022QE028,ZR2021QE116,and ZR2020KE027).
文摘Micro-grinding with a spherical grinding head has been deemed an indispensable method in high-risk surgeries, such as neurosurgery and spine surgery, where bone grinding has long been plagued by the technical bottleneck of mechanical stress-induced crack damage. In response to this challenge, the ultrasound-assisted biological bone micro-grinding novel process with a spherical grinding head has been proposed by researchers. Force modeling is a prerequisite for process parameter determination in orthopedic surgery, and the difculty in establishing and accurately predicting bone micro-grinding force prediction models is due to the geometric distribution of abrasive grains and the dynamic changes in geometry and kinematics during the cutting process. In addressing these critical needs and technical problems, the shape and protrusion heights of the wear particle of the spherical grinding head were frst studied, and the gradual rule of the contact arc length under the action of high-speed rotating ultrasonic vibration was proposed. Second, the mathematical model of the maximum thickness of undeformed chips under ultrasonic vibration of the spherical grinding head was established. Results showed that ultrasonic vibration can reduce the maximum thickness of undeformed chips and increase the range of ductile and bone meal removals, revealing the mechanism of reducing grinding force. Further, the dynamic grinding behavior of diferent layers of abrasive particles under diferent instantaneous interaction states was studied. Finally, a prediction model of micro-grinding force was established in accordance with the relationship between grinding force and cutting depth, revealing the mechanism of micro-grinding force transfer under ultrasonic vibration. The theoretical model’s average deviations are 10.37% in x-axis direction, 6.85% in y-axis direction, and 7.81% in z-axis direction compared with the experimental results. This study provides theoretical guidance and technical support for clinical bone micro-grinding.
基金Supported by the Focally Deployed Program,Center for Ocean Mega-Science,Chinese Academy of Sciences,National Natural Science Foundation(No.COMS2019R03)the National Natural Science Foundation of China(No.31972791)+2 种基金the Earmarked Fund for Agriculture Seed Improvement Project of Shandong Province(No.2020LZGC016)the Earmarked Fund for Shandong Modern Agro-Industry Technology Research System(No.SDAIT-14)the Natural Science Foundation of Shandong Province(No.ZR2020MC192)。
文摘As“Bohai Red”scallops were originated from the hybrids between the Peruvian scallop(Argopecten purpuratus)and the bay scallop(Argopecten irradians)northern subspecies(Argopecten irradians irradians).Twelve Wnt members were identified from the two subspecies of bay scallop,and 13 Wnt genes were found in the genome of the Peruvian scallop.Protein structure analyses showed that most Wnt genes poses all 5 conserved motifs except Wnt1,Wnt2,Wnt6,and Wnt9 in the bay scallops and Wnt2 and Wnt9 in the Peruvian scallop.Unexpectedly,Wnt8 gene was present while Wnt3 was absent in both the bay scallops and the Peruvian scallop.Phylogenetic analysis revealed that Wnt3 might have disappeared in the early evolution of mollusks.The expression profile of Wnt genes in the“Bohai Red”exposed to different temperatures was examined by qRT-PCR.Results show that expression of Wnt genes responded differentially to temperature changes.The Wnt genes such as Wnt1,Wnt6,Wnt7,Wnt11,and WntA that responded slowly to low and high temperature stresses may be related to the maintenance of basic homeostasis.Other Wnt genes such as Wnt4,Wnt9,Wnt5,and Wnt2 that responded rapidly to low temperature may play an important role in organismal protection against low temperature stress.And yet some Wnt genes including Wnt10,Wnt16,and Wnt8 that responded quickly to high temperature stress may play key roles in response to high temperature stress.The results provide new insights into the evolution and function of Wnt genes in bivalves and eventually benefit culture of“Bohai Red”scallops.
基金supported by the National Key R&D Program of China (2022YFC2303403)National Natural Science Foundation of China (82225021)supported by the Chinese Academy of Sciences (YSBR-010 and Y2022037)。
文摘Following the outbreak of coronavirus disease 2019(COVID-19),several severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-related coronaviruses have been discovered.Previous research has identified a novel lineage of SARS-CoV-2-related CoVs in bats,including RsYN04,which recognizes human angiotensin-converting enzyme 2(ACE2)and thus poses a potential threat to humans.Here,we screened the binding of the RsYN04receptor-binding domain(RBD)to ACE2 orthologs from 52animal species and found that the virus showed a narrower ACE2-binding spectrum than SARS-CoV-2.However,the presence of the T484W mutation in the RsYN04 RBD broadened its range.We also evaluated 44 SARS-CoV-2antibodies targeting seven epitope communities in the SARS-CoV-2 RBD,together with serum obtained from COVID-19 convalescents and vaccinees,to determine their cross-reaction against RsYN04.Results showed that no antibodies,except for the RBD-6 and RBD-7 classes,bound to the RsYN04 RBD,indicating substantial immune differences from SARS-CoV-2.Furthermore,the structure of the RsYN04 RBD in complex with cross-reactive antibody S43 in RBD-7 revealed a potently broad epitope for the development of therapeutics and vaccines.Our findings suggest RsYN04 and other viruses belonging to the same clade have the potential to infect several species,including humans,highlighting the necessity for viral surveillance and development of broad anticoronavirus countermeasures.
基金supported in part by the National Natural Science Foundation of China under Grants No.62027803,No.61601096,No.61971111,and No.61801089in part by the Science and Technology Program under Grants No.8091C24,No.2021JCJQJJ0949,and No.2022JCJQJJ0784in part by the Industrial Technology Development Program under Grant No.2020110C041.
文摘Kernel adaptive filters(KAFs)have sparked substantial attraction for online non-linear learning applications.It is noted that the effectiveness of KAFs is highly reliant on a rational learning criterion.Concerning this,the logarithmic hyperbolic cosine(lncosh)criterion with better robustness and convergence has drawn attention in recent studies.However,existing lncosh loss-based KAFs use the stochastic gradient descent(SGD)for optimization,which lack a trade-off between the convergence speed and accuracy.But recursion-based KAFs can provide more effective filtering performance.Therefore,a Nyström method-based robust sparse kernel recursive least lncosh loss algorithm is derived in this article.Experiments via measures and synthetic data against the non-Gaussian noise confirm the superiority with regard to the robustness,accuracy performance,and computational cost.
基金supported by Key-Area Research and Development Program of Guangdong Province(2021B0101420002)the Major Key Project of PCL(PCL2021A09)+3 种基金National Natural Science Foundation of China(62072187)Guangdong Major Project of Basic and Applied Basic Research(2019B030302002)Guangdong Marine Economic Development Special Fund Project(GDNRC[2022]17)Guangzhou Development Zone Science and Technology(2021GH10,2020GH10).
文摘Nowadays,the rapid development of edge computing has driven an increasing number of deep learning applications deployed at the edge of the network,such as pedestrian and vehicle detection,to provide efficient intelligent services to mobile users.However,as the accuracy requirements continue to increase,the components of deep learning models for pedestrian and vehicle detection,such as YOLOv4,become more sophisticated and the computing resources required for model training are increasing dramatically,which in turn leads to significant challenges in achieving effective deployment on resource-constrained edge devices while ensuring the high accuracy performance.For addressing this challenge,a cloud-edge collaboration-based pedestrian and vehicle detection framework is proposed in this paper,which enables sufficient training of models by utilizing the abundant computing resources in the cloud,and then deploying the well-trained models on edge devices,thus reducing the computing resource requirements for model training on edge devices.Furthermore,to reduce the size of the model deployed on edge devices,an automatic pruning method combines the convolution layer and BN layer is proposed to compress the pedestrian and vehicle detection model size.Experimental results show that the framework proposed in this paper is able to deploy the pruned model on a real edge device,Jetson TX2,with 6.72 times higher FPS.Meanwhile,the channel pruning reduces the volume and the number of parameters to 96.77%for the model,and the computing amount is reduced to 81.37%.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFB3601600)the National Natural Science Foundation of China(Grant Nos.12104216,61427812,11774160,51971109,51871236,51771053,U1806219)+1 种基金the Natural Science Foundation of Jiangsu Province of China(Grant Nos.BK20200307,BK20192006,BK20180056)the Fundamental Research Funds for the Central Universities(Grant No.21014380113)。
文摘Research of spin polarization of magnetic CoFeB thin films is of practical importance in spintronic applications.Here,using a direct characterization technique of spin-resolved photoemission spectroscopy,we obtain the surface spin polarization of amorphous Co_(40)Fe_(40)B_(20)thin films with different annealing temperatures from 100℃to 500℃prepared by magnetron sputtering.After high annealing temperature,a quasi-semiconductor state is gradually formed at the CoFeB surface due to the boron diffusion.While the global magnetization remains almost constant,the secondary electrons’spin polarization,average valence band spin polarization and the spin polarization at Fermi level from spin-resolved photoemission spectroscopy show a general trend of decreasing with the increasing annealing temperature above 100℃.These distinct surface properties are attributed to the enhanced Fe-B bonding due to the boron segregation upon surface after annealing as confirmed by x-ray photoelectron spectroscopy and scanning transmission electron microscopy with energy dispersive spectroscopy.Our findings provide insight into the surface spin-resolved electronic structure of the CoFeB thin films,which should be important for development of high-performance magnetic random-access memories.
基金supported by the National Natural Science Foundation of China(Grant Nos.42141019 and 42261144687)the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(Grant No.2019QZKK0102)+4 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB42010404)the National Natural Science Foundation of China(Grant No.42175049)the Guangdong Meteorological Service Science and Technology Research Project(Grant No.GRMC2021M01)the National Key Scientific and Technological Infrastructure project“Earth System Science Numerical Simulator Facility”(EarthLab)for computational support and Prof.Shiming XIANG for many useful discussionsNiklas BOERS acknowledges funding from the Volkswagen foundation.
文摘Climate models are vital for understanding and projecting global climate change and its associated impacts.However,these models suffer from biases that limit their accuracy in historical simulations and the trustworthiness of future projections.Addressing these challenges requires addressing internal variability,hindering the direct alignment between model simulations and observations,and thwarting conventional supervised learning methods.Here,we employ an unsupervised Cycle-consistent Generative Adversarial Network(CycleGAN),to correct daily Sea Surface Temperature(SST)simulations from the Community Earth System Model 2(CESM2).Our results reveal that the CycleGAN not only corrects climatological biases but also improves the simulation of major dynamic modes including the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole mode,as well as SST extremes.Notably,it substantially corrects climatological SST biases,decreasing the globally averaged Root-Mean-Square Error(RMSE)by 58%.Intriguingly,the CycleGAN effectively addresses the well-known excessive westward bias in ENSO SST anomalies,a common issue in climate models that traditional methods,like quantile mapping,struggle to rectify.Additionally,it substantially improves the simulation of SST extremes,raising the pattern correlation coefficient(PCC)from 0.56 to 0.88 and lowering the RMSE from 0.5 to 0.32.This enhancement is attributed to better representations of interannual,intraseasonal,and synoptic scales variabilities.Our study offers a novel approach to correct global SST simulations and underscores its effectiveness across different time scales and primary dynamical modes.
基金supported by the National Natural Science Foundation of China(Grant Nos.41925012,42230710)Key Laboratory Cooperation Special Project of Western Cross Team of Western Light,Chinese Academy of Sciences(Grant No.xbzg-zdsys-202107).
文摘Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking.This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey soils.To validate the feasibility and efficacy of the proposed approach,direct tensile tests were employed to determine the tensile strength of the compacted soil with different W-OH treatment concentrations and water contents.Desiccation tests were also performed to evaluate the effectiveness of W-OH treatment in enhancing soil tensile cracking resistance.During this period,the effects of W-OH treatment concentration and water content on tensile properties,soil suction and microstructure were investigated.The tensile tests reveal that W-OH treatment has a significant impact on the tensile strength and failure mode of the soil,which not only effectively enhances the tensile strength and failure displacement,but also changes the brittle failure behavior into a more ductile quasi-brittle failure behavior.The suction measurements and mercury intrusion porosimetry(MIP)tests show that W-OH treatment can slightly reduce soil suction by affecting skeleton structure and increasing macropores.Combined with the microstructural analysis,it becomes evident that the significant improvement in soil tensile behavior through W-OH treatment is mainly attributed to the W-OH gel's ability to provide additional binding force for bridging and encapsulating the soil particles.Moreover,desiccation tests demonstrate that W-OH treatment can significantly reduce or even inhibit the formation of soil tensile cracking.With the increase of W-OH treatment concentration,the surface crack ratio and total crack length are significantly reduced.This study enhances a fundamental understanding of eco-polymer impacts on soil mechanical properties and provides valuable insight into their potential application for improving soil crack resistance.
基金supported by the Program for National Defense Science and Technology Foundation Strengtheningthe Youth Foundation of Rocket Force University of Engineering(Grant No.2021QN-B014)。
文摘A submerged cavitation water jet(SCWJ)is an effective method to recycle solid propellant from obsolete solid engines by the breaking method.Solid propellant's breaking modes and mechanical process under SCWJ impact are unclear.This study aims to understand those impact breaking mechanisms.The hydroxyl-terminated polybutadiene(HTPB)propellant was chosen as the research material,and a self-designed test system was used to conduct impact tests at four different working pressures.The high-speed camera characterized crack propagation,and the DIC method calculated strain change during the impact process.Besides,micro and macro fracture morphologies were characterized by scanning electron microscope(SEM)and computed tomography(CT)scanning.The results reveal that the compressive strain concentration region locates right below the nozzle,and the shear strain region distributes symmetrically with the jet axis,which increases to 4% at first 16th ms,the compressive strain rises to 2% and 6% in the axial and transverse direction,respectively.The two tensile cracks formed first at the compression strain concentrate region,and there generate many shear cracks around the tensile cracks,and those shear cracks that develop and aggregate cause the cracks to become wider and cut through the tensile cracks,forming the tensile-shear cracks and the impact parts eventually fail.The HTPB propellant forms a breaking hole shaped conical after impact 10 s.The mass loss increases by 17 times at maximum,with the working pressure increasing by three times.Meanwhile,the damage value of the breaking hole remaining on the surface increases by 7.8 times while 2.9 times in the depth of the breaking hole.The breaking efficiency is closely affected by working pressures.The failure modes of HTPB impacted by SCWJ are classified as tensile crack-dominated and tensile-shear crack-dominated damage mechanisms.
基金funded by the National Natural Science Foundation of China(32072490)the National Key R&D Program of China(2021YFC2600100 and2021YFC2600101)the Agricultural Science and Technology Innovation Program,China。
文摘Mikania micrantha is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production.It has advantages in photosynthesis,including a similar net photosynthetic rate as C4 plants and a higher carbon fixation capacity.We used a combination of genomics and transcriptomics approaches to study the evolutionary mechanisms and circadian expression patterns of M.micrantha.In M.micrantha,16 positive selection genes focused on photoreaction and utilization of photoassimilates.In different tissues,98.1%of the genes associated with photoresponse had high expression in stems,and more than half of the genes of the C4 cycle had higher expression in stems than in leaves.In stomatal opening and closing,2 genes of carbonic anhydrase(CAs)had higher expression at 18:00 than at 8:00,and the slow anion channel 1(SLAC1)and high-leaf-temperature 1 kinase(HT1)genes were expressed at low levels at 18:00.In addition,genes associated with photosynthesis had higher expression levels at 7:00 and 17:00.We hypothesized that M.micrantha may undergo photosynthesis in the stem and flower organs and that some stomata of the leaves were opening at night by CO_(2)signals.In addition,its evolution may attenuate photoinhibition at high light intensities,and enhance more efficient of photosynthesis during low light intensity.And the tissue-specific photosynthetic types and different diurnal pattern of photosynthetic-related genes may contribute to its rapid colonization of new habitats of M.micrantha.
基金supported by Key R&D Program of Zhejiang Province,China (No.2022C03061)the National Natural Science Foundation of China (No.52074204)the Fundamental Research Funds for the Central Universities (No.2023-vb-032).
文摘The proper recycling of spent lithium-ion batteries(LIBs)can promote the recovery and utilization of valuable resources,while also negative environmental effects resulting from the presence of toxic and hazardous substances.In this study,a new environmentally friendly hydro-metallurgical process was proposed for leaching lithium(Li),nickel(Ni),cobalt(Co),and manganese(Mn)from spent LIBs using sulfuric acid with citric acid as a reductant.The effects of the concentration of sulfuric acid,the leaching temperature,the leaching time,the solid-liquid ratio,and the reducing agent dosage on the leaching behavior of the above elements were investigated.Key parameters were optimized using response surface methodology(RSM)to maximize the recovery of metals from spent LIBs.The maxim-um recovery efficiencies of Li,Ni,Co,and Mn can reach 99.08%,98.76%,98.33%,and 97.63%.under the optimized conditions(the sulfuric acid concentration was 1.16 mol/L,the citric acid dosage was 15wt%,the solid-liquid ratio was 40 g/L,and the temperature was 83℃ for 120 min),respectively.It was found that in the collaborative leaching process of sulfuric acid and citric acid,the citric acid initially provided strong reducing CO_(2)^(-),and the transition metal ions in the high state underwent a reduction reaction to produce transition metal ions in the low state.Additionally,citric acid can also act as a proton donor and chelate with lower-priced transition metal ions,thus speeding up the dissolution process.
基金This work was supported by the Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX02)the National Natural Science Foundation of China(No.12005282)+1 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2021283)the Shanghai Pilot Program for Basic Research—Chinese Academy of Science,Shanghai Branch(JCYJSHFY-2021-010).
文摘The Shanghai high-repetition-rate X-ray free-electron laser and extreme light facility(SHINE)operates at a maximum repetition rate of 1 MHz.Kicker magnets are key components that distribute electron bunches into three different undulator lines in a bunch-by-bunch mode.The kicker field width must be less than the time interval between bunches.A lumpedinductance kicker prototype was developed using a vacuum chamber with a single-turn coil.The full magnetic field strength was 0.005 T.This paper presents the requirements,design considerations,design parameters,magnetic field calculations,and measurements of the kicker magnets.The relevant experimental results are also presented.The pulse width of the magnetic field was approximately 600 ns,and the maximum operation repetition rate was 1 MHz.The developed kicker satisfies the requirements for the SHINE project.Finally,numerous recommendations for the future optimization of kicker magnets are provided.
基金supported by Key Science and Technology Innovation Team of Shaanxi Province(No.2022TD-33)National Natural Science Foundation of China(Grant Nos.21373161,21504067)。
文摘Traditional selection of combustion catalysis is time-consuming and labor-intensive.Theoretical calculation is expected to resolve this problem.The adsorption energy of HMX and O atoms on 13 metal oxides was calculated using DMol3,since HMX and O are key substances in decomposition process.And the relationship between the adsorption energy of HMX,O on metal oxides(TiO_(2),Al_(2)O_(3),PbO,CuO,Fe_(2)O_(3),Co_(3)O_(4),Bi_(2)O_(3),NiO)and experimental T30 values(time required for the decomposition depth of HMX to reach 30%)was depicted as volcano plot.Thus,the T30 values of other metal oxides was predicted based on their adsorption energy on volcano plot and validated by previous experimental data.Further,the adsorption energy of HMX on ZrO_(2)and MnO_(2)was predicted based on the linear relationship between surface energy and adsorption energy,and T30 values were estimated based on volcano plot.The apparent activation energy data of HMX/MgO,HMX/SnO_(2),HMX/ZrO_(2),and HMX/MnO_(2)obtained from DSC experiments are basically consistent with our predicted T30 values,indicating that it is feasible to predict the catalytic activity based on the adsorption calculation,and it is expected that these simple structural properties can predict adsorption energy to reduce the large quantities of computation and experiment cost.
文摘Reactive transport modeling(RTM)is an emerging method used to address geological issues in diagenesis research.However,the extrapolation of RTM results to practical reservoir prediction is not sufficiently understood.This paper presents a case study of the Eocene Qaidam Basin that combines RTM results with petrological and mineralogical evidence.The results show that the Eocene Xiaganchaigou Formation is characterized by mixed siliciclastic-carbonate-evaporite sedimentation in a semiclosed saline lacustrine environment.Periodic evaporation and salinization processes during the syngeneticpenecontemporaneous stage gave rise to the replacive genesis of dolomites and the cyclic enrichment of dolomite in the middle-upper parts of the meter-scale depositional sequences.The successive change in mineral paragenesis from terrigenous clastics to carbonates to evaporites was reconstructed using RTM simulations.Parametric uncertainty analyses further suggest that the evaporation intensity(brine salinity)and particle size of sediments(reactive surface area)were important rate-determining factors in the dolomitization,as shown by the relatively higher reaction rates under conditions of higher brine salinity and fine-grained sediments.Combining the simulation results with measured mineralogical and reservoir physical property data indicates that the preservation of original intergranular pores and the generation of porosity via replacive dolomitization were the major formation mechanisms of the distinctive lacustrine dolomite reservoirs(widespread submicron intercrystalline micropores)in the Eocene Qaidam Basin.The results confirm that RTM can be effectively used in geological studies,can provide a better general understanding of the dolomitizing fluid-rock interactions,and can shed light on the spatiotemporal evolution of mineralogy and porosity during dolomitization and the formation of lacustrine dolomite reservoirs.