Quantitative geomorphic analyses are usually powerful in identifying active tectonics across global orogenic belts.Our present study will focus on the Anatolian Plate which hosts a lot of recent catastrophic earthquak...Quantitative geomorphic analyses are usually powerful in identifying active tectonics across global orogenic belts.Our present study will focus on the Anatolian Plate which hosts a lot of recent catastrophic earthquakes in Türkiye.Six geomorphic indices for 100 sub-basins around Türkiye have been computed including local relief,slope,normalized steepness index(k_(Sn)),hypsometric curve and integral(HI),transverse topographic symmetry factor(Tf),and the basin asymmetry factor(Af).The averaged kSnand Af values have shown four high-value anomalous zones,suggesting relatively high uplift rates featured by high river incision and regional tilting.The values of 0.35≤HI<0.6 for basins with S-shaped curves imply intensive tectonic activities along the eastern part of the North Anatolian Fault Zone(NAFZ),the Northeast Anatolian Fault Zone(NEAFZ),the East Anatolian Fault Zone(EAFZ),and the Central Anatolian Fault Zone(CAFZ).All results of the geomorphic indices analysis suggest a relatively high degree of tectonic activity in the following four areas,the Isparta Angle,the Eastern Black Sea Mountains,the South-eastern Anatolia Region,and the Central Anatolian fault zone.We further suggest that the eastern part of the NAFZ,NEAFZ,EAFZ,and CAFZ will be more active in tectonic activities,with a greater potential for strong earthquake occurrence.展开更多
Adsorption dynamics of ethane in two granular fixed beds and structured fixed beds with microfibrous composites was studied.5A zeolite membrane 5A/PSSF(paper-like sintered stainless steel fiber)and microfibrous entrap...Adsorption dynamics of ethane in two granular fixed beds and structured fixed beds with microfibrous composites was studied.5A zeolite membrane 5A/PSSF(paper-like sintered stainless steel fiber)and microfibrous entrapped activated carbon(MEAC)composites were prepared by wet layup papermaking/sintering technique and in-situ hydrothermal method.Microfibrous composites were characterized by X-ray diffraction,scanning electron microscopy and N2 adsorption/desorption.Structured fixed beds were designed by filling granular adsorbents(5A zeolite or activated carbon)and microfibrous composites at the inlet and outlet of the beds,respectively.Effects of flow rate,bed height and structure on the breakthrough curves were investigated.The length of unused bed(LUB)was determined,and Yoon–Nelson model was used to fit the breakthrough curves.The experimental results showed ethane was effectively adsorbed on the granular adsorbents and microfibrous composites.Both composites could decrease the LUB values and enhance bed utilization.All breakthrough curves fitted well to Yoon–Nelson model,with correlation coefficient exceeding 0.89.The adsorption rate of ethane could be improved in the structured fixed beds,which showed an enhanced mass transfer efficiency for ethane adsorption.LUB values of structured fixed beds with 5A/PSSF composites were larger,the bed utilization values were lower,and the adsorption rate constants were higher than those with MEAC composites under the same conditions.展开更多
Single-cell or low-input multi-omics techniques have revolutionized the study of pre-implantation embryo development.However,the single-cell or low-input proteomic research in this field is relatively underdeveloped b...Single-cell or low-input multi-omics techniques have revolutionized the study of pre-implantation embryo development.However,the single-cell or low-input proteomic research in this field is relatively underdeveloped because of the higher threshold of the starting material for mammalian embryo samples and the lack of hypersensitive proteome technology.In this study,a comprehensive solution of ultrasensitive proteome technology(CS-UPT)was developed for single-cell or low-input mouse oocyte/embryo samples.The deep coverage and high-throughput routes significantly reduced the starting material and were selected by investigators based on their demands.Using the deep coverage route,we provided the first large-scale snapshot of the very early stage of mouse maternal-to-zygotic transition,including almost 5,500 protein groups from 20 mouse oocytes or zygotes for each sample.Moreover,significant protein regulatory networks centered on transcription factors and kinases between the MII oocyte and 1-cell embryo provided rich insights into minor zygotic genome activation.展开更多
Ethylene thiourea(ETU)converted from ethylene bisdithiocarbamate(EBDC)fungicides has aroused great concern because of its prevalence and harmful effects.Although ETU-induced neurotoxicity has been reported,the potenti...Ethylene thiourea(ETU)converted from ethylene bisdithiocarbamate(EBDC)fungicides has aroused great concern because of its prevalence and harmful effects.Although ETU-induced neurotoxicity has been reported,the potential mechanisms remain unclear.This study provided insights into its neurotoxic effects at environmentally relevant concentrations in zebrafish.Our findings showed that embryonic exposure to ETU decreased the hatch rate and delayed somite development.Furthermore,ETU treatment significantly reduced the dark velocity in the locomotion assay.The upregulated tendency of the mitogen-activated protein kinases(MAPK)pathway(mknk1,atf4,mapkapk3)screened by transcriptome analysis implied motor neuron degeneration,which was validated by subsequent morphological observation,as axon length and branches were truncated in the 62.5μg/L ETU group.However,although the rescue experiment with a p38 MAPK inhibitor(SB203580)successfully ameliorated axon degeneration,it failed to reverse the locomotion behaviors.Further exploration of transcriptome data revealed the varied expression of presynaptic scaffold protein-related genes(pcloa,pclob,bsna),whose downregulation might impair the neuromuscular junction(NMJ).Therefore,we reasonably suspected that ETU-induced neurobehavioral deficits might result from the combined effects of the MAPK pathway and presynaptic proteins.Considering this,we highlighted the necessity to take precautions and early interventions for susceptible ETU-exposed populations.展开更多
At GMT time 13:19, August 8, 2017, an M1.0 earthquake struck the Jiuzhaigou region in Sichuan Province, China, causing severe damages and casualties. To investigate the source properties, seismogenic structures, and ...At GMT time 13:19, August 8, 2017, an M1.0 earthquake struck the Jiuzhaigou region in Sichuan Province, China, causing severe damages and casualties. To investigate the source properties, seismogenic structures, and seismic hazards, we systematically analyzed the tectonic environment, crustal velocity structure in the source region, source parameters and rupture process, Coulomb failure stress changes, and 3-D features of the rupture plane of the Jiuzhaigou earthquake. Our results indicate the following: (1) The Jiuzhaigou earthquake occurred on an unmarked fault belonging to the transition zone of the east Kunlun fault system and is located northwest of the Huya fault. (2) Both the mainshock and aftershock rupture zones are located in a region where crustal seismic velocity changes dramatically. Southeast to the source region, shear wave velocity at the middle to lower crust is significantly low, but it rapidly increases northeastward and lies close to the background velocity across the rupture fault. (3) The aftershock zone is narrow and distributes along the northwest-southeast trend, and most aftershocks occur within a depth range of 5-20 km. (4) The focal mechanism of the Jiuzhaigou earthquake indicates a left-lateral strike-slip fault, with strike, dip, and rake angles of 152~, 74~ and 8~, respectively. The hypocenter depth measures 20 km, whereas the centroid depth is about 6 kin. The co-seismic rupture mainly concentrates at depths of 3-13 km, with a moment magnitude (Mw) of 6.5. (5) The co-seismic rupture also strengthens the Coulomb failure stress at the two ends of the rupture fault and the east segment of the Tazang fault. Aftershocks relocation results together with geological surveys indicate that the causative fault is a near vertical fault with notable spatial variations: dip angle varies within 660-89~ from northwest to southeast and the average dip angle measures -84~. The results of this work are of fundamental importance for further studies on the source characteristics, tectonic environment, and seismic hazard evaluation of the Jiuzhaigou earthquake.展开更多
Langshan, a monoclinic mountain, which started to uplift since Oligocene, bounds the northwest margin of the Hetao Basin. The continuous activity of the active normal Langshan range- front fault forms the typical basi...Langshan, a monoclinic mountain, which started to uplift since Oligocene, bounds the northwest margin of the Hetao Basin. The continuous activity of the active normal Langshan range- front fault forms the typical basin-and-range landform in Langshan area and controls the landform evolution of Langshan. Langshan is an ideal place to study relationship between quantitative geomor- phological index and active deformation. According to study on knickpoints, fitting on longitudinal channel profiles and steepness index, we demonstrate that the main controlling factors on distribution of normalized steepness index of channels are not climate (precipitation), lithology, sediment flux, but tectonic factor, or the activity of Langshan range-front fault. The short channels in southeast flank, whose lengths are shorter than 16 km, may be still in the non-steady status. If not considering these short channels, the distribution of normalized steepness index along the Langshan range-front fault appears like M-shape pattern, while the normalized steepness index in the middle section is higher than those at both ends. This pattern is well consistent with geometrical segmentation model of the Langshan range-front fault. Combining previous active tectonic research on Langshan range-front fault, which demonstrates the Langshan range-front fault has been in the stage of linkup, we reasonably infer the Langshan range-front fault now is the result of linkup of both fault which continuously bilaterally ex- tended independently. Our tectonic geomorphological study also supports the conclusion that the Langshan range-front fault has been in the stage of linkup. The formation of several knickpoints due to tectonic factor may have been caused by slip-rate variation because of linkup of both independent faults. Based on cognition above, we also proposed the geological and geomorphological evolutionary model of the Langshan range-front fault since Oligocene.展开更多
Carbon molecular sieve membrane(CMSM)/paper-like stainless steel fibers(PSSF)has been manufactured by pyrolyzing poly(fiirfuryl alcohol)(PFA)coated on the metal fibers.PFA was synthesized using oxalic acid dihydrate a...Carbon molecular sieve membrane(CMSM)/paper-like stainless steel fibers(PSSF)has been manufactured by pyrolyzing poly(fiirfuryl alcohol)(PFA)coated on the metal fibers.PFA was synthesized using oxalic acid dihydrate as a catalyst and coated on microfibers by dip coating method.For the purpose of investigating the effects of final carbonization temperature,the composites were carbonized between 400℃ and 800℃ under flowing nitrogen.The morphology and microstructure were examined by X-ray diffraction,Fourier transforms infrared spectroscopy,scanning electron microscopy,thermogravimetric analysis,N2 adsorption and desorption,Raman spectra and X-ray photoelectron spectra.The consequences of characterization showed that the CMSM containing mesopores o f 3.9 nm were manufactured.The specific surface area of the CMSM/PSSF fabricated in different pyrolysis temperature varies from 26.5 to 169.1 m^2·g^-1 and pore volume varies from 0.06 to 0.23 cm^3·g^-1.When pyrolysis temperature exceeds 600℃,the specific surface,pore diameter and pore volume decreased as carbonization temperature increased.Besides,the degree of graphitization in carbon matrix increased with rising pyrolysis temperature.Toluene adsorption experiments on different structured fixed bed that was padded by CMSM/PSSF and granular activated carbon(GAC)were conducted.For the sake of comparison,adsorption test was also performed on fixed bed packed with GAC.The experimental results indicated that the rate constant κ′ was dramatically increased as the proportion of CMCM/PSSF composites increased on the basis of Yoon-Nelson model,which suggested that structured fixed bed padded with CMSM/PSSF composite offered higher adsorption rate and mass transfer efficiency.展开更多
Direct separation of Xe and Kr from air or used nuclear fuel(UNF)off-gas by means of porous adsorbents is of industrial importance but is a very challenging task.In this work,we show a robust metal-organic framework(M...Direct separation of Xe and Kr from air or used nuclear fuel(UNF)off-gas by means of porous adsorbents is of industrial importance but is a very challenging task.In this work,we show a robust metal-organic framework(MOF),namely ECUT-60,which renders not only high chemical stability,but also unique structure with multiple traps.This leads to the ultrahigh Xe adsorption capacity,exceeding most reported porous materials.Impressively,this MOF also enables high selectivity of Xe over Kr,CO2,O2,and N2,leading to the high-performance separation for trace quantitites of Xe/Kr from a simulated UNF reprocessing off-gas.The separation capability has been demonstrated by using dynamic breakthrough experiments,giving the record Xe uptake up to 70.4 mmol/kg and the production of 19.7 mmol/kg pure Xe.Consequently,ECUT-60 has promising potential in direct production of Xe from UNF off-gas or air.The separation mechanism,as unveiled by theoretical calculation,is attributed to the multiple traps in ECUT-60 that affords rigid restrict for Xe atom via van der Waals force.展开更多
River is one of the geomorphic units that are the most sensitive to tectonic activity, of which the longitudinal profile serves as a key archieve to record information on active tectonics. The stream-power incision mo...River is one of the geomorphic units that are the most sensitive to tectonic activity, of which the longitudinal profile serves as a key archieve to record information on active tectonics. The stream-power incision model is an important means to analyze channel long profiles and to extract both temporal and spatial patterns of regional tectonic activity. Analytical solutions to the steady-state and linear transient-state equations of the model provides means to calibrate drainage basin concavity,calculate channel steepness index, determine drainage divide stability, project the paleo-channel profile, and to invert the tectonic uplift rate history. Yet, not all of these functions have been implemented in the published open-source tools. Here, we developed a set of open-source codes, RiverProAnalysis, which was based on the Matlab platform and integrated all of these functions. The products of the tool set are in the format of image, text and vector files, which not only can be used for visual analysis, but be read by softwares of geographic information system. Taking examples of two transient drainage catchments in the northern margin of the Taiyuan Basin, we analyzed the long profiles of the trunk streams, identified two generations of knickpoints, and estimated the minimum amount of river incision. We combined all the trunk and tributary channels together to model the catchment-wide uplift history and found moderate increases in the uplift rates since the Middle Pliocene and rapid accelation since the late Quaternary. The inverted results are consistent with the sedimentary records in the adjacent basin. By comparing the chi value,slope, and topographic relief of both sides of the catchment divide, we concluded the stability of the drainage divide. Our tool set integrates the main functions of the modern studies on fluvial landsape, thus providing a powerful tool for analyzing river long profiles and for understanding tectonic geomorphology.展开更多
The SE Tibetan Plateau,tectonically situated in the eastern India-Eurasia oblique convergence zone,has experienced multiple stages of deformation since the Cenozoic.Three major tectonic boundaries—the Ailaoshan-Red R...The SE Tibetan Plateau,tectonically situated in the eastern India-Eurasia oblique convergence zone,has experienced multiple stages of deformation since the Cenozoic.Three major tectonic boundaries—the Ailaoshan-Red River,ChongshanLincang-Inthanon,and Gaoligong-Mogok shear zones—delineate the first-order tectonic framework in this region.The most striking structural features in the block interiors are a series of NW-and NE-trending fault systems,such as the Dayingjiang,Longlin-Ruili,Nantinghe,Red River,Weixi-Qiaohou,and Lancang-Genma faults,which have conjugate geometric relationships.In this study,we review these structures’geometric and kinematic characteristics and deformation histories.A synthesis of existing geological observations,geomorphological analyses,and chronological data reveals three major Cenozoic tectonothermal events,including crustal shortening,strike-slip shearing,and kinematic reversal.The boundary structures controlled the tectonic extrusion of plateau material during the early Oligocene-early Miocene.In the mid-late Miocene,NW-and NE-trending fault systems mostly experienced diachronous slip-sense inversions.The onset and spatial trend of regional kinematic reversal are constrained by existing chronologic data.Together with geophysical and geodetic observations,the activity and geodynamic drivers of the major fault systems and regional deformation styles are explored,revealing that the SE Tibetan Plateau underwent a transition from discrete(lateral block extrusion)to diffuse deformation in the mid-late Miocene.The intracontinental crustal deformation and its coupling with dynamic processes at depth during the plateau growth are discussed in the context of the IndiaEurasia convergence.展开更多
This article aims to study the geomorpometric features of alluvial fans since they act as a small-scale geomorphic unit response to tectonics and climate changes around the Chaka-Qinghai Lake area in the northeastern ...This article aims to study the geomorpometric features of alluvial fans since they act as a small-scale geomorphic unit response to tectonics and climate changes around the Chaka-Qinghai Lake area in the northeastern Tibetan Plateau. We quantitatively extracted geomorphic parameters, such as the surface area and slope of alluvial fans adjacent to the Qinghai Nan Shan and Ela Shan. Alluvial fans in the Chaka Lake partition area, south of the Qinghai Nan Shan, are featured by a small area and short length, but the largest slope. Geomorphic parameters of the alluvial fans in Ela Shan area are in- termediate in size, and the alluvial fans in the Qinghai Lake partition area north of Qinghai Nan Shan have the gentlest slope. Together with the regional faulting activity analysis, we suggest that the alluvial fans with the high slopes in the south of Qinghai Nan Shan are mainly controlled by the reverse faulting along the Qinghai Nan Shan faults, and the strike-slip movement of the Eia Shan fault zone plays a weak role. In contrast, due to the lack of active faults, the alluvial fans near the Qinghai Lake area north of the Qinghai Nan Shan only respond to regional erosion, transportation, and deposition proc- esses, thereby forming relatively gentle geomorphic units.展开更多
Microwave(MW)assisted catalyst-free hydrolysis of fibrous cellulose(FC,cellulolysis)at 200℃promoted a cellulose conversion o f ca.37.2%and quantitative production o f valuable C5/C6 sugars(e.g.,glucose)and the accord...Microwave(MW)assisted catalyst-free hydrolysis of fibrous cellulose(FC,cellulolysis)at 200℃promoted a cellulose conversion o f ca.37.2%and quantitative production o f valuable C5/C6 sugars(e.g.,glucose)and the according platform biochemicals(e.g.,5-hydroxymethylfurfliral),corresponding to an overall selectivity o f 96.5%.Conversely,conventional hydrothermal cellulolysis under similar conditions was not effective,even after 24 h,carbonising the FC.Based on the systematic study of MW-assisted cellulolysis,the specific interaction between water molecules and macroscopic FC under the MW irradiation was proposed,accounting for the interpretation o f the experimental observation.The kinetic energy o f water molecules under the MW irradiation facilitated the C-C(in the non-hindered surface-CH2OH groups)and C-O-C bond breaking(inside the cellulose cavities)in FC,producing primary cellulolysis products of xylose,glucose and cellobiose.展开更多
Accurately forecasting short-term electricity prices is of great significance to electricity market participants.Compared with the time series forecasting methods,machine learning forecasting methods can consider more...Accurately forecasting short-term electricity prices is of great significance to electricity market participants.Compared with the time series forecasting methods,machine learning forecasting methods can consider more external factors.The forecasting accuracy of machine learning models is greatly affected by the parameters,meanwhile,the manual selection of parameters usually cannot guarantee the accuracy and stability of the forecasting.Therefore,this paper proposes a random forest(RF)electricity price forecasting model based on the grey wolf optimizer(GWO)to improve the accuracy of forecasting.Among them,RF has a good ability to deal with the problem of non-linear and unstable electricity prices.The optimization of model parameters by GWO can overcome the instability of the forecasting accuracy of manually tune parameters.On this basis,the short-term electricity prices of the PJM power market in four seasons are separately predicted.Experimental results show that the RF algorithm can better predict the short-term electricity price,and the optimization of the RF forecasting model by GWO can effectively improve the accuracy of the RF forecasting model.展开更多
The reticular chemistry strategy presents a powerful molecule-design tool to tailor the physical and chemical properties of metal-organic framework(MOF).In this work,we for the first time investigated the effect of or...The reticular chemistry strategy presents a powerful molecule-design tool to tailor the physical and chemical properties of metal-organic framework(MOF).In this work,we for the first time investigated the effect of organic ligands on the radionuclide sequestration(TcO_(4)^(-))of thorium-organic framework.Through a coordination modulation technique,two novel isoreticular thorium-organic frameworks,namely Th-MOF-67 and Th-MOF-68,were obtained.Relative to the antetype MOF of Th-MOF-66 that shows extremely low uptake of ReO_(4)^(-)(a chemical surrogate of radioactive TcO_(4)^(-)),the isoreticular MOFs of Th-MOF-67 and Th-MOF-68 enable ultrahigh uptake of ReO_(4)^(-),giving an impressively 36.8-fold or 56-fold enhancement,respectively.The adsorption capacity of Th-MOF-68 is as high as 560 mg/g,exceeding most reported adsorbents for such use.The mechanism for such exceptional outstanding performance,as unveiled by both the single crystal X-ray diffraction and theoretical calculation,is due to coordination interaction for Th-MOF-67,when a tetrazolate ligand was used,or a combined effect from both coordination interaction and anion-exchange for Th-MOF-68,if using a triazolate ligand.展开更多
Landscape evolution in active orogen region is inevitably affected by landslides associated with strong earthquakes, rain or storm. However, quantitative studies of the orogenic or eroded volumes are rarely demonstrat...Landscape evolution in active orogen region is inevitably affected by landslides associated with strong earthquakes, rain or storm. However, quantitative studies of the orogenic or eroded volumes are rarely demonstrated. The 2008 Wenchuan Earthquake triggered serious landsliding, consequently, a large amount of landslide material. However, the landslide volume is estimated mainly on the landslides areas interpreted in their semi-automated landslide mapping algorithm. However, the total volume of landslides triggered by the Wenchuan Earthquake amounts to 5-10 times bigger than the expected upper bound according to the empirical correlation between "total landslide volume" and "moment magnitude". Here we show that the total landslide volume estimation has large uncertainties to be used to determine whether the Wenchuan Earthquake generates or reduces relief. Thus, the widely held view that large dip-slip and oblique-slip earthquakes build mountainous topography may still be applicable to the Wenchuan Earthquake in Longmen Shan area. To challenge this view, simple landslide volume and co-seismic uplift comparison is not enough, i.e., more data are needed.展开更多
Previous researches had emphasized tectonic impacts on the fluvial system at the tectonically active areas,while the effects of lithology and local base level change have received relatively rare attention.Here we inv...Previous researches had emphasized tectonic impacts on the fluvial system at the tectonically active areas,while the effects of lithology and local base level change have received relatively rare attention.Here we investigated fluvial landforms at different spatial scales,focusing on knickpoints and channel network reorganization from an area affected by the Haiyuan Fault in the northeastern Tibetan Plateau.The geomorphic indices,i.e.,drainage pattern andχanomalies,were calculated and investigated.The results show that two regional radial drainages formed around the Laohu and Hasi Mountains.Within the interior of the radial drainage,tributaries from the southeast side of the Laohu Mountain experienced near 180°direction change.We interpret this as the gradual drainage capture originating from the height difference(~190 m)of the local base level between the two catchments.Some tributaries from the Hasi Mountain show alternating gorges and broad valleys controlled by lithology.Besides,tectonic uplift and the lowering of base level(from the incision of the Yellow River)triggered an autogenic positivefeedback transition from parallel to dendritic drainage patterns.These observations suggest that base level change and lithology play a crucial role in landscape evolution,even in a tectonically active region.展开更多
The citrate secreted by the rice(Oryza sativa L.)roots will promote the absorption of phosphate,and this process is described by the Kirk model.In our work,the Kirk model is divided into citrate sub-model and phosphat...The citrate secreted by the rice(Oryza sativa L.)roots will promote the absorption of phosphate,and this process is described by the Kirk model.In our work,the Kirk model is divided into citrate sub-model and phosphate sub-model.In the citrate sub-model,we obtain the analytical solution of citrate with the Laplace transform,inverse Laplace transform and convolution theorem.The citrate solution is substituted into the phosphate sub-model,and the analytical solution of phosphate is obtained by the separation variable method.The existence of the solutions can be proved by the comparison test,the Weierstrass M-test and the Abel discriminating method.展开更多
基金supported by the Key Research and Development Plan of Yunnan Province:The Technology of the Comprehensive Risk Assessment of the Earthquake Catastrophe and the Disaster Chains in Yunnan and Its Application(No.202203AC100003)Institute of Geology,China Earthquake Administration(No.IGCEA2302)。
文摘Quantitative geomorphic analyses are usually powerful in identifying active tectonics across global orogenic belts.Our present study will focus on the Anatolian Plate which hosts a lot of recent catastrophic earthquakes in Türkiye.Six geomorphic indices for 100 sub-basins around Türkiye have been computed including local relief,slope,normalized steepness index(k_(Sn)),hypsometric curve and integral(HI),transverse topographic symmetry factor(Tf),and the basin asymmetry factor(Af).The averaged kSnand Af values have shown four high-value anomalous zones,suggesting relatively high uplift rates featured by high river incision and regional tilting.The values of 0.35≤HI<0.6 for basins with S-shaped curves imply intensive tectonic activities along the eastern part of the North Anatolian Fault Zone(NAFZ),the Northeast Anatolian Fault Zone(NEAFZ),the East Anatolian Fault Zone(EAFZ),and the Central Anatolian Fault Zone(CAFZ).All results of the geomorphic indices analysis suggest a relatively high degree of tectonic activity in the following four areas,the Isparta Angle,the Eastern Black Sea Mountains,the South-eastern Anatolia Region,and the Central Anatolian fault zone.We further suggest that the eastern part of the NAFZ,NEAFZ,EAFZ,and CAFZ will be more active in tectonic activities,with a greater potential for strong earthquake occurrence.
基金support from the National Natural Science Foundation of China(21776101)the National Natural Science Foundation of China(22178122)for this work.
文摘Adsorption dynamics of ethane in two granular fixed beds and structured fixed beds with microfibrous composites was studied.5A zeolite membrane 5A/PSSF(paper-like sintered stainless steel fiber)and microfibrous entrapped activated carbon(MEAC)composites were prepared by wet layup papermaking/sintering technique and in-situ hydrothermal method.Microfibrous composites were characterized by X-ray diffraction,scanning electron microscopy and N2 adsorption/desorption.Structured fixed beds were designed by filling granular adsorbents(5A zeolite or activated carbon)and microfibrous composites at the inlet and outlet of the beds,respectively.Effects of flow rate,bed height and structure on the breakthrough curves were investigated.The length of unused bed(LUB)was determined,and Yoon–Nelson model was used to fit the breakthrough curves.The experimental results showed ethane was effectively adsorbed on the granular adsorbents and microfibrous composites.Both composites could decrease the LUB values and enhance bed utilization.All breakthrough curves fitted well to Yoon–Nelson model,with correlation coefficient exceeding 0.89.The adsorption rate of ethane could be improved in the structured fixed beds,which showed an enhanced mass transfer efficiency for ethane adsorption.LUB values of structured fixed beds with 5A/PSSF composites were larger,the bed utilization values were lower,and the adsorption rate constants were higher than those with MEAC composites under the same conditions.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.:82030099,30700397 Detail)the National Key R&D Program of China(Grant No.:2022YFD2101500)+5 种基金the Science and Technology Commission of Shanghai Municipality,China(Grant No.:22DZ2303000)the Shanghai Municipal Science and Technology Commission“Science and Technology Innovation Action Plan”Technical Standard Project,China(Grant No.:21DZ2201700)the Shanghai Municipal Science and Technology Commission“Science and Technology Innovation Action Plan”Natural Science Foundation Project,China(Grant No.:23ZR1435800)the Strategic Priority Research Program of the Chinese Academy of Sciences,China(Grant No.:XDB32060000)the Basic Frontier Scientific Research Program of Chinese Academy of Sciences(Grant No.:ZDBS-LY-SM019)the Yangfan Project of Shanghai Science and Technology Commission,China(Grant No.:22YF1454100),and the Innovative Research Team of High-level Local Universities in Shanghai,China.
文摘Single-cell or low-input multi-omics techniques have revolutionized the study of pre-implantation embryo development.However,the single-cell or low-input proteomic research in this field is relatively underdeveloped because of the higher threshold of the starting material for mammalian embryo samples and the lack of hypersensitive proteome technology.In this study,a comprehensive solution of ultrasensitive proteome technology(CS-UPT)was developed for single-cell or low-input mouse oocyte/embryo samples.The deep coverage and high-throughput routes significantly reduced the starting material and were selected by investigators based on their demands.Using the deep coverage route,we provided the first large-scale snapshot of the very early stage of mouse maternal-to-zygotic transition,including almost 5,500 protein groups from 20 mouse oocytes or zygotes for each sample.Moreover,significant protein regulatory networks centered on transcription factors and kinases between the MII oocyte and 1-cell embryo provided rich insights into minor zygotic genome activation.
基金supported by the National Key R&D Program of China (Nos.2018YFC1004300 and 2018YFC1004304)。
文摘Ethylene thiourea(ETU)converted from ethylene bisdithiocarbamate(EBDC)fungicides has aroused great concern because of its prevalence and harmful effects.Although ETU-induced neurotoxicity has been reported,the potential mechanisms remain unclear.This study provided insights into its neurotoxic effects at environmentally relevant concentrations in zebrafish.Our findings showed that embryonic exposure to ETU decreased the hatch rate and delayed somite development.Furthermore,ETU treatment significantly reduced the dark velocity in the locomotion assay.The upregulated tendency of the mitogen-activated protein kinases(MAPK)pathway(mknk1,atf4,mapkapk3)screened by transcriptome analysis implied motor neuron degeneration,which was validated by subsequent morphological observation,as axon length and branches were truncated in the 62.5μg/L ETU group.However,although the rescue experiment with a p38 MAPK inhibitor(SB203580)successfully ameliorated axon degeneration,it failed to reverse the locomotion behaviors.Further exploration of transcriptome data revealed the varied expression of presynaptic scaffold protein-related genes(pcloa,pclob,bsna),whose downregulation might impair the neuromuscular junction(NMJ).Therefore,we reasonably suspected that ETU-induced neurobehavioral deficits might result from the combined effects of the MAPK pathway and presynaptic proteins.Considering this,we highlighted the necessity to take precautions and early interventions for susceptible ETU-exposed populations.
基金supported by the Training Program for Academic and Technical Leaders of Major Disciplines in Jiangxi Province(20194BCJ22010)the National Natural Science Foundations of China(21966002)+1 种基金the Youth Leading Talent Project of Fuzhou(2020ED64)Jiangxi Project(DHSQT22021007).
基金funded by the Seismological Bureau Spark Program Project(Grant No.XH15007)the National Natural Science Foundation of China(Grant Nos.41604058,41574057,41621091)the Sichuan-Yunnan National Seismological Monitoring and Prediction Experimental Station Project(Grant No.2016CESE0204)
文摘At GMT time 13:19, August 8, 2017, an M1.0 earthquake struck the Jiuzhaigou region in Sichuan Province, China, causing severe damages and casualties. To investigate the source properties, seismogenic structures, and seismic hazards, we systematically analyzed the tectonic environment, crustal velocity structure in the source region, source parameters and rupture process, Coulomb failure stress changes, and 3-D features of the rupture plane of the Jiuzhaigou earthquake. Our results indicate the following: (1) The Jiuzhaigou earthquake occurred on an unmarked fault belonging to the transition zone of the east Kunlun fault system and is located northwest of the Huya fault. (2) Both the mainshock and aftershock rupture zones are located in a region where crustal seismic velocity changes dramatically. Southeast to the source region, shear wave velocity at the middle to lower crust is significantly low, but it rapidly increases northeastward and lies close to the background velocity across the rupture fault. (3) The aftershock zone is narrow and distributes along the northwest-southeast trend, and most aftershocks occur within a depth range of 5-20 km. (4) The focal mechanism of the Jiuzhaigou earthquake indicates a left-lateral strike-slip fault, with strike, dip, and rake angles of 152~, 74~ and 8~, respectively. The hypocenter depth measures 20 km, whereas the centroid depth is about 6 kin. The co-seismic rupture mainly concentrates at depths of 3-13 km, with a moment magnitude (Mw) of 6.5. (5) The co-seismic rupture also strengthens the Coulomb failure stress at the two ends of the rupture fault and the east segment of the Tazang fault. Aftershocks relocation results together with geological surveys indicate that the causative fault is a near vertical fault with notable spatial variations: dip angle varies within 660-89~ from northwest to southeast and the average dip angle measures -84~. The results of this work are of fundamental importance for further studies on the source characteristics, tectonic environment, and seismic hazard evaluation of the Jiuzhaigou earthquake.
基金funded jointly by the National Natural Science Foundation of China (Nos. 41402187, 41372220, 41590861, 41661134011)
文摘Langshan, a monoclinic mountain, which started to uplift since Oligocene, bounds the northwest margin of the Hetao Basin. The continuous activity of the active normal Langshan range- front fault forms the typical basin-and-range landform in Langshan area and controls the landform evolution of Langshan. Langshan is an ideal place to study relationship between quantitative geomor- phological index and active deformation. According to study on knickpoints, fitting on longitudinal channel profiles and steepness index, we demonstrate that the main controlling factors on distribution of normalized steepness index of channels are not climate (precipitation), lithology, sediment flux, but tectonic factor, or the activity of Langshan range-front fault. The short channels in southeast flank, whose lengths are shorter than 16 km, may be still in the non-steady status. If not considering these short channels, the distribution of normalized steepness index along the Langshan range-front fault appears like M-shape pattern, while the normalized steepness index in the middle section is higher than those at both ends. This pattern is well consistent with geometrical segmentation model of the Langshan range-front fault. Combining previous active tectonic research on Langshan range-front fault, which demonstrates the Langshan range-front fault has been in the stage of linkup, we reasonably infer the Langshan range-front fault now is the result of linkup of both fault which continuously bilaterally ex- tended independently. Our tectonic geomorphological study also supports the conclusion that the Langshan range-front fault has been in the stage of linkup. The formation of several knickpoints due to tectonic factor may have been caused by slip-rate variation because of linkup of both independent faults. Based on cognition above, we also proposed the geological and geomorphological evolutionary model of the Langshan range-front fault since Oligocene.
基金The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China(Grant No.21776106)Pearl River S&T Nova Program of Guangzhou(Grant No.201610010171)for this work.
文摘Carbon molecular sieve membrane(CMSM)/paper-like stainless steel fibers(PSSF)has been manufactured by pyrolyzing poly(fiirfuryl alcohol)(PFA)coated on the metal fibers.PFA was synthesized using oxalic acid dihydrate as a catalyst and coated on microfibers by dip coating method.For the purpose of investigating the effects of final carbonization temperature,the composites were carbonized between 400℃ and 800℃ under flowing nitrogen.The morphology and microstructure were examined by X-ray diffraction,Fourier transforms infrared spectroscopy,scanning electron microscopy,thermogravimetric analysis,N2 adsorption and desorption,Raman spectra and X-ray photoelectron spectra.The consequences of characterization showed that the CMSM containing mesopores o f 3.9 nm were manufactured.The specific surface area of the CMSM/PSSF fabricated in different pyrolysis temperature varies from 26.5 to 169.1 m^2·g^-1 and pore volume varies from 0.06 to 0.23 cm^3·g^-1.When pyrolysis temperature exceeds 600℃,the specific surface,pore diameter and pore volume decreased as carbonization temperature increased.Besides,the degree of graphitization in carbon matrix increased with rising pyrolysis temperature.Toluene adsorption experiments on different structured fixed bed that was padded by CMSM/PSSF and granular activated carbon(GAC)were conducted.For the sake of comparison,adsorption test was also performed on fixed bed packed with GAC.The experimental results indicated that the rate constant κ′ was dramatically increased as the proportion of CMCM/PSSF composites increased on the basis of Yoon-Nelson model,which suggested that structured fixed bed padded with CMSM/PSSF composite offered higher adsorption rate and mass transfer efficiency.
基金supported by the National Natural Science Foundations of China(21966002 and 21871047)the Natural Science Foundation of Jiangxi Province(20181ACB20003)+1 种基金the Training Program for Academic and Technical Leaders of Major Disciplines in Jiangxi Province(20194BCJ22010)the Graduate Innovation Project of East China University of Technology(DHYC-202023)。
文摘Direct separation of Xe and Kr from air or used nuclear fuel(UNF)off-gas by means of porous adsorbents is of industrial importance but is a very challenging task.In this work,we show a robust metal-organic framework(MOF),namely ECUT-60,which renders not only high chemical stability,but also unique structure with multiple traps.This leads to the ultrahigh Xe adsorption capacity,exceeding most reported porous materials.Impressively,this MOF also enables high selectivity of Xe over Kr,CO2,O2,and N2,leading to the high-performance separation for trace quantitites of Xe/Kr from a simulated UNF reprocessing off-gas.The separation capability has been demonstrated by using dynamic breakthrough experiments,giving the record Xe uptake up to 70.4 mmol/kg and the production of 19.7 mmol/kg pure Xe.Consequently,ECUT-60 has promising potential in direct production of Xe from UNF off-gas or air.The separation mechanism,as unveiled by theoretical calculation,is attributed to the multiple traps in ECUT-60 that affords rigid restrict for Xe atom via van der Waals force.
基金supported by the National Natural Science Foundation of China (Grant No. 41802227)。
文摘River is one of the geomorphic units that are the most sensitive to tectonic activity, of which the longitudinal profile serves as a key archieve to record information on active tectonics. The stream-power incision model is an important means to analyze channel long profiles and to extract both temporal and spatial patterns of regional tectonic activity. Analytical solutions to the steady-state and linear transient-state equations of the model provides means to calibrate drainage basin concavity,calculate channel steepness index, determine drainage divide stability, project the paleo-channel profile, and to invert the tectonic uplift rate history. Yet, not all of these functions have been implemented in the published open-source tools. Here, we developed a set of open-source codes, RiverProAnalysis, which was based on the Matlab platform and integrated all of these functions. The products of the tool set are in the format of image, text and vector files, which not only can be used for visual analysis, but be read by softwares of geographic information system. Taking examples of two transient drainage catchments in the northern margin of the Taiyuan Basin, we analyzed the long profiles of the trunk streams, identified two generations of knickpoints, and estimated the minimum amount of river incision. We combined all the trunk and tributary channels together to model the catchment-wide uplift history and found moderate increases in the uplift rates since the Middle Pliocene and rapid accelation since the late Quaternary. The inverted results are consistent with the sedimentary records in the adjacent basin. By comparing the chi value,slope, and topographic relief of both sides of the catchment divide, we concluded the stability of the drainage divide. Our tool set integrates the main functions of the modern studies on fluvial landsape, thus providing a powerful tool for analyzing river long profiles and for understanding tectonic geomorphology.
基金supported by the Natural Science Foundation of Guangdong Province(Grant Nos.2021A1515011631,202102020490 and 2019B1515120019)the National Natural Science Foundation of China(Grant Nos.U1701641 and41802213)+1 种基金the Second Tibetan Plateau Scientific Expedition and Research Program(STEP,Grant No.2019QZKK0703)Guangdong Province Introduced Innovative and R&D Team of Geological Processes and Natural Disasters around the South China Sea(Grant No.2016ZT06N331)。
文摘The SE Tibetan Plateau,tectonically situated in the eastern India-Eurasia oblique convergence zone,has experienced multiple stages of deformation since the Cenozoic.Three major tectonic boundaries—the Ailaoshan-Red River,ChongshanLincang-Inthanon,and Gaoligong-Mogok shear zones—delineate the first-order tectonic framework in this region.The most striking structural features in the block interiors are a series of NW-and NE-trending fault systems,such as the Dayingjiang,Longlin-Ruili,Nantinghe,Red River,Weixi-Qiaohou,and Lancang-Genma faults,which have conjugate geometric relationships.In this study,we review these structures’geometric and kinematic characteristics and deformation histories.A synthesis of existing geological observations,geomorphological analyses,and chronological data reveals three major Cenozoic tectonothermal events,including crustal shortening,strike-slip shearing,and kinematic reversal.The boundary structures controlled the tectonic extrusion of plateau material during the early Oligocene-early Miocene.In the mid-late Miocene,NW-and NE-trending fault systems mostly experienced diachronous slip-sense inversions.The onset and spatial trend of regional kinematic reversal are constrained by existing chronologic data.Together with geophysical and geodetic observations,the activity and geodynamic drivers of the major fault systems and regional deformation styles are explored,revealing that the SE Tibetan Plateau underwent a transition from discrete(lateral block extrusion)to diffuse deformation in the mid-late Miocene.The intracontinental crustal deformation and its coupling with dynamic processes at depth during the plateau growth are discussed in the context of the IndiaEurasia convergence.
基金supported by the Fund of the Insti-tute of Geology,CEA(No.IGCEA1115)the National Natural Science Foundation of China(Nos.41203012,41272196)
文摘This article aims to study the geomorpometric features of alluvial fans since they act as a small-scale geomorphic unit response to tectonics and climate changes around the Chaka-Qinghai Lake area in the northeastern Tibetan Plateau. We quantitatively extracted geomorphic parameters, such as the surface area and slope of alluvial fans adjacent to the Qinghai Nan Shan and Ela Shan. Alluvial fans in the Chaka Lake partition area, south of the Qinghai Nan Shan, are featured by a small area and short length, but the largest slope. Geomorphic parameters of the alluvial fans in Ela Shan area are in- termediate in size, and the alluvial fans in the Qinghai Lake partition area north of Qinghai Nan Shan have the gentlest slope. Together with the regional faulting activity analysis, we suggest that the alluvial fans with the high slopes in the south of Qinghai Nan Shan are mainly controlled by the reverse faulting along the Qinghai Nan Shan faults, and the strike-slip movement of the Eia Shan fault zone plays a weak role. In contrast, due to the lack of active faults, the alluvial fans near the Qinghai Lake area north of the Qinghai Nan Shan only respond to regional erosion, transportation, and deposition proc- esses, thereby forming relatively gentle geomorphic units.
文摘Microwave(MW)assisted catalyst-free hydrolysis of fibrous cellulose(FC,cellulolysis)at 200℃promoted a cellulose conversion o f ca.37.2%and quantitative production o f valuable C5/C6 sugars(e.g.,glucose)and the according platform biochemicals(e.g.,5-hydroxymethylfurfliral),corresponding to an overall selectivity o f 96.5%.Conversely,conventional hydrothermal cellulolysis under similar conditions was not effective,even after 24 h,carbonising the FC.Based on the systematic study of MW-assisted cellulolysis,the specific interaction between water molecules and macroscopic FC under the MW irradiation was proposed,accounting for the interpretation o f the experimental observation.The kinetic energy o f water molecules under the MW irradiation facilitated the C-C(in the non-hindered surface-CH2OH groups)and C-O-C bond breaking(inside the cellulose cavities)in FC,producing primary cellulolysis products of xylose,glucose and cellobiose.
文摘Accurately forecasting short-term electricity prices is of great significance to electricity market participants.Compared with the time series forecasting methods,machine learning forecasting methods can consider more external factors.The forecasting accuracy of machine learning models is greatly affected by the parameters,meanwhile,the manual selection of parameters usually cannot guarantee the accuracy and stability of the forecasting.Therefore,this paper proposes a random forest(RF)electricity price forecasting model based on the grey wolf optimizer(GWO)to improve the accuracy of forecasting.Among them,RF has a good ability to deal with the problem of non-linear and unstable electricity prices.The optimization of model parameters by GWO can overcome the instability of the forecasting accuracy of manually tune parameters.On this basis,the short-term electricity prices of the PJM power market in four seasons are separately predicted.Experimental results show that the RF algorithm can better predict the short-term electricity price,and the optimization of the RF forecasting model by GWO can effectively improve the accuracy of the RF forecasting model.
基金supported financially by the Natural Science Foundation of Jiangxi Province of China(No.20181ACB20003)the Training Program for Academic and Technical Leaders of Major Disciplines in Jiangxi Province(No.20194BCJ22010)the National Natural Science Foundations of China(Nos.21966002 and 21871047).
文摘The reticular chemistry strategy presents a powerful molecule-design tool to tailor the physical and chemical properties of metal-organic framework(MOF).In this work,we for the first time investigated the effect of organic ligands on the radionuclide sequestration(TcO_(4)^(-))of thorium-organic framework.Through a coordination modulation technique,two novel isoreticular thorium-organic frameworks,namely Th-MOF-67 and Th-MOF-68,were obtained.Relative to the antetype MOF of Th-MOF-66 that shows extremely low uptake of ReO_(4)^(-)(a chemical surrogate of radioactive TcO_(4)^(-)),the isoreticular MOFs of Th-MOF-67 and Th-MOF-68 enable ultrahigh uptake of ReO_(4)^(-),giving an impressively 36.8-fold or 56-fold enhancement,respectively.The adsorption capacity of Th-MOF-68 is as high as 560 mg/g,exceeding most reported adsorbents for such use.The mechanism for such exceptional outstanding performance,as unveiled by both the single crystal X-ray diffraction and theoretical calculation,is due to coordination interaction for Th-MOF-67,when a tetrazolate ligand was used,or a combined effect from both coordination interaction and anion-exchange for Th-MOF-68,if using a triazolate ligand.
基金funded by the National Natural Science Foundation of China (No. 41102136)the National Nonprofit Fundamental Research Grant of China (No. IGCEA1119)the Foundation of Returned Overseas Scholars of China (to Dr. Zhikun Ren)
文摘Landscape evolution in active orogen region is inevitably affected by landslides associated with strong earthquakes, rain or storm. However, quantitative studies of the orogenic or eroded volumes are rarely demonstrated. The 2008 Wenchuan Earthquake triggered serious landsliding, consequently, a large amount of landslide material. However, the landslide volume is estimated mainly on the landslides areas interpreted in their semi-automated landslide mapping algorithm. However, the total volume of landslides triggered by the Wenchuan Earthquake amounts to 5-10 times bigger than the expected upper bound according to the empirical correlation between "total landslide volume" and "moment magnitude". Here we show that the total landslide volume estimation has large uncertainties to be used to determine whether the Wenchuan Earthquake generates or reduces relief. Thus, the widely held view that large dip-slip and oblique-slip earthquakes build mountainous topography may still be applicable to the Wenchuan Earthquake in Longmen Shan area. To challenge this view, simple landslide volume and co-seismic uplift comparison is not enough, i.e., more data are needed.
基金supported by the National Natural Science Foundation of China(Grant Nos.41971005,41522101)the Second Tibetan Plateau Scientific Expedition Program(Grant No.2019QZKK0205)the National Key Research and Development Program(Grant No.2016YFA0600500)。
文摘Previous researches had emphasized tectonic impacts on the fluvial system at the tectonically active areas,while the effects of lithology and local base level change have received relatively rare attention.Here we investigated fluvial landforms at different spatial scales,focusing on knickpoints and channel network reorganization from an area affected by the Haiyuan Fault in the northeastern Tibetan Plateau.The geomorphic indices,i.e.,drainage pattern andχanomalies,were calculated and investigated.The results show that two regional radial drainages formed around the Laohu and Hasi Mountains.Within the interior of the radial drainage,tributaries from the southeast side of the Laohu Mountain experienced near 180°direction change.We interpret this as the gradual drainage capture originating from the height difference(~190 m)of the local base level between the two catchments.Some tributaries from the Hasi Mountain show alternating gorges and broad valleys controlled by lithology.Besides,tectonic uplift and the lowering of base level(from the incision of the Yellow River)triggered an autogenic positivefeedback transition from parallel to dendritic drainage patterns.These observations suggest that base level change and lithology play a crucial role in landscape evolution,even in a tectonically active region.
基金support of the Natural Science Foundations.of China(11671085,11501111 and 11771082)Leading project in Fujian Province(2015Y0054)Nonlinear Analysis and Its Applications(19120/Z1607219016,IRTL1206).
文摘The citrate secreted by the rice(Oryza sativa L.)roots will promote the absorption of phosphate,and this process is described by the Kirk model.In our work,the Kirk model is divided into citrate sub-model and phosphate sub-model.In the citrate sub-model,we obtain the analytical solution of citrate with the Laplace transform,inverse Laplace transform and convolution theorem.The citrate solution is substituted into the phosphate sub-model,and the analytical solution of phosphate is obtained by the separation variable method.The existence of the solutions can be proved by the comparison test,the Weierstrass M-test and the Abel discriminating method.