The practical application of lithium-sulfur(Li-S)batteries is greatly hindered by soluble polysulfides shuttling and sluggish sulfur redox kinetics.Rational design of multifunctional hybrid materials with superior ele...The practical application of lithium-sulfur(Li-S)batteries is greatly hindered by soluble polysulfides shuttling and sluggish sulfur redox kinetics.Rational design of multifunctional hybrid materials with superior electronic conductivity and high electrocatalytic activity,e.g.,heterostructures,is a promising strategy to solve the above obstacles.Herein,a binary metal sulfide MnS-MoS_(2) heterojunction electrocatalyst is first designed for the construction of high-sulfur-loaded and durable Li-S batteries.The MnS-MoS_(2) p-n heterojunction shows a unique structure of MoS_(2) nanosheets decorated with ample MnS nanodots,which contributes to the formation of a strong built-in electric field at the two-phase interface.The MnS-MoS_(2) hybrid host shows strong soluble polysulfide affinity,enhanced electronic conductivity,and exceptional catalytic effect on sulfur reduction.Benefiting from the synergistic effect,the as-derived S/MnS-MoS_(2) cathode delivers a superb rate capability(643 m A h g^(-1)at 6 C)and a durable cyclability(0.048%decay per cycle over 1000 cycles).More impressively,an areal capacity of 9.9 m A h cm^(-2)can be achieved even under an extremely high sulfur loading of 14.7 mg cm^(-2)and a low electrolyte to sulfur ratio of 2.9μL mg^(-1).This work provides an in-depth understanding of the interfacial catalytic effect of binary metal compound heterojunctions on sulfur reaction kinetics.展开更多
The concentration and velocity fields of two refractive index matched miscible shear-thinning fluids in a lid-driven cavity were investigated by using planar laser-induced fluorescence and particle image velocimetry,a...The concentration and velocity fields of two refractive index matched miscible shear-thinning fluids in a lid-driven cavity were investigated by using planar laser-induced fluorescence and particle image velocimetry,as well by computational fluid dynamics.Quantitative analyses show that the results obtained by flow simulations with the species transport model are in good agreement with the experimental results.The effects of different parameters were studied by using the intensity of segregation.For two fluids with the same rheological parameters,the relative amounts of liquids H_(1)/H and the power-law index n dominate the mixing process while the Reynolds number Re plays a marginal role.As for two fluids with density difference,buoyancy has significant influence on the mixing process.The dimensionless group Ar/Re(redefined such as to include shear thinning behavior)is proposed for assessing the effect of buoyancy and rheological properties on the mixing of miscible shear-thinning fluids.展开更多
The economic alga Neopyropia,which holds significant value in China for its edibility and economic potential,harbors diverse epiphytic bacteria on its surface.The epiphytic bacteria on Neopyropia yezoensis and Neopyro...The economic alga Neopyropia,which holds significant value in China for its edibility and economic potential,harbors diverse epiphytic bacteria on its surface.The epiphytic bacteria on Neopyropia yezoensis and Neopyropia katadae,two nori species of Neopyropia living at the same tidal level but with distinct physiological states and living habits,were investigated to understand the differences between them and the effects of epiphytic bacteria on their differential characteristics.Analysis of 16S rRNA gene sequences and real-time quantitative PCR(qPCR)of thalli and seawater samples(n=24)revealed notable differences in microbial diversity and community structure between the two species.Bacteroidetes dominated the bacterial communities in association with N.yezoensis,whereas Proteobacteria were predominant in N.katadae.Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt2)analysis revealed enriched genes that related to the ABC transport system,iron complex outer membrane receptor proteins,and proliferation in N.yezoensis,whereas N.katadae exhibited enrichment of genes that related to energy supply as well as cell wall and cell membrane production.The results of qPCR indicate a higher abundance of epiphytic bacteria on surface of N.yezoensis than those on surface of N.katadae.The findings indicate that differences in the living environments of N.yezoensis and N.katadae may result in distinct structural composition and abundance of epiphytic bacteria on their surfaces,thereby conferring specific biological functionalities to each microbial community,and the epiphytic bacteria may shape the living habits of hosts to some extents.This study provided a basis for understanding the close association between surface microorganisms and algal bodies,and the physiological and ecological characteristics of nori species.展开更多
As the rapid development of more powerful and safer lithiumion batteries, the mechanism study of gases evolution is attacking more and more attention in recent years. Especially under overcharge/discharge and/or high-...As the rapid development of more powerful and safer lithiumion batteries, the mechanism study of gases evolution is attacking more and more attention in recent years. Especially under overcharge/discharge and/or high-temperature working condition.展开更多
With less extra stress on the testing sample, a free-stress sample holder was designed to place the sample horizontally. With the free-stress sample holder, a magnetoelectric (ME) coefficient measurement system was de...With less extra stress on the testing sample, a free-stress sample holder was designed to place the sample horizontally. With the free-stress sample holder, a magnetoelectric (ME) coefficient measurement system was developed based on dynamic method. This measurement system has the hardware part and the software part, integrated by the DC magnetic field generation module, the AC magnetic field generation module, the induced ME voltage detecting module and PC software module. Then, a sample of Terfenol-D/PZT/Terfenol-D trilayer was designed and fabricated, and the relationships of its ME coefficient influenced by the DC magnetic field and the frequency of the AC magnetic field were tested using the measurement system. And the results showed that the free-stress sample holder was proven to improve the accuracy of the measurement system by less stress interference.展开更多
To the complication and uncertainty in coal seam floor water-inrush monitoring, Internet of Things (IoT) perception is applied to the monitoring and controlling of coal seam floor water inrush with major impacting fac...To the complication and uncertainty in coal seam floor water-inrush monitoring, Internet of Things (IoT) perception is applied to the monitoring and controlling of coal seam floor water inrush with major impacting factors analyzed, and an open distribution information processing platform is constructed based on IoT-GIS coupling perception. Then using the platform to comprehensively perceive various floor water inrush impacting parameters, an AHP model is established. At this stage, by means of weight reasoning algorithm based on dynamic Bayesian network, the AHP weight can be worked out using the two-way probability transfer and chain rules. Then the multiple factors are spatially fused by GIS to form a non-linear mathematical model for the calculation of the water inrush relative probability index. After that, the discrimination threshold of the comb graph for the floor water inrush relative probability index is used to further identify the floor water inrush mode. The experiments in 10# Coal Seam of Suntuan Mine show that, the accuracy perceived the floor water inrush is above 92%, and the platform of IoT-GIS coupling perception has the obvious technical advantage than traditional monitoring technology. Therefore, it has has demonstrated strong systematic robustness, important theoretical and application significance.展开更多
Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway ...Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway network in cluster of orthologous groups(COG)and Kyoto Encyclopedia of Genes and Genomes(KEGG),and carbohydrate-active enzymes(CAZymes)were explored in metagenomic analysis.DNA extraction from gametophytes of P.haitanensis was performed first,followed by library construction,sequencing,preprocessing of sequencing data,taxonomy assignment,gene prediction,and functional annotation.The results show that the predominant microorganisms of P.haitanensis were bacteria(98.98%),and the phylum with the highest abundance was Proteobacteria(54.64%),followed by Bacteroidetes(37.92%).Erythrobacter(3.98%)and Hyunsoonleella jejuensis(1.56%)were the genera and species with the highest abundance of bacteria,respectively.The COG annotation demonstrated that genes associated with microbial metabolism was the predominant category.The results of metabolic pathway annotation show that the ABC transport system and two-component system were the main pathways in the microbial community.Plant growth hormone biosynthesis pathway and multi-vitamin biosynthesis functional units(modules)were the other important pathways.The CAZyme annotation revealed that the starch might be an important carbon source for microorganisms.Glycosyl transferase family 2(GT2)and glycosyl transferase family 3(GT3)were the highly abundant families in glucoside transferase superfamily.Six metagenome-assembled genomes containing enzymes involved in the biosynthesis of cobalamin(vitamin B 12)and indole-3-acetic acid were obtained by binning method.They were confirmed to belong to Rhodobacterales and Rhizobiales,respectively.Our findings provide comprehensive insights into the microorganism community of Pyropia.展开更多
The genus Pyropia contains several important cultivated species.Genetic research in nori species has mainly focused on the cell nucleus,with few studies on organelles(chloroplast and mitochondria).Due to the high copy...The genus Pyropia contains several important cultivated species.Genetic research in nori species has mainly focused on the cell nucleus,with few studies on organelles(chloroplast and mitochondria).Due to the high copy numbers of organelles in cells,which influence the development and traits of algae,it is necessary to study their genetic mechanism.In this study,the marine red alga Pyropia yezoensis,an important economic macroalga,was selected as the study object.To investigate organelle(chloroplast and mitochondria)inheritance in P.yezoensis,the wild type RZ(maternal strain)was crossed with the red mutant HT(paternal strain)and 30 color-sectors from 11 F1 gametophytic blades were examined.The complete chloroplast and mitochondrial genomes of the red mutant(HT)were assembled for the first time.One reliable and stable single nucleotide polymorphism(SNP)loci filtrated by bioinformatics analysis was used as a molecular marker for chloroplast and mitochondrial DNA,respectively,in subsequent experiments.PCR amplification and sequence analysis showed that the haplotypes of color-sectors detected were consistent with those of the maternal parent,confirming that both chloroplast and mitochondrial genomes were inherited maternally in P.yezoensis.The inheritance pattern of organelles in P.yezoensis can be used to guide the hybridization and breeding of nori.Additionally,the organelle SNP markers developed in this study can be applied in subsequent genetic research.展开更多
Pyropia yezoensis is an important macroalga because of its extensive global distribution and economic importance.Color is an important trait in the thalli of P.yezoensis,it is also an effective marker to identify the ...Pyropia yezoensis is an important macroalga because of its extensive global distribution and economic importance.Color is an important trait in the thalli of P.yezoensis,it is also an effective marker to identify the hybridization in genetic breeding.In this study,a high-density genetic linkage map was constructed based on high-throughput single nucleotide polymorphism(SNP)markers,and used for analyzing the quantitative trait loci(QTLs)of red color trait in the thalli of P.yezoensis.The conchospore undergoes meiosis to develop into an ordered tetrad,and each cell has a haploid phenotype and can grow into a single individual.Based on this theory,F1 haploid population was used as the mapping population.The map included 531 SNP markers,394.57 cM long on average distance of 0.74 cM.Collinear analysis of the genetic linkage map and the physical map indicated that the coverage between the two maps was 79.42%.Furthermore,QTL mapping identified six QTLs for the chromosomal regions associated with the red color trait of the thalli.The value of phenotypic variance explained(PVE)by an individual QTL ranged from 4.71%-63.11%.And QTL qRed-1-1,with a PVE of 63.11%,was considered the major QTL.Thus,these data may provide a platform for gene and QTL fine mapping,and marker-assisted breeding in P.yezoensis in the future.展开更多
Hydrogels electrolytes with flexibility and high conductivity have been widely used in kinds of flexible electronics.However,hydrogels always suffer from the inevitable freezing of water at subzero temperatures,which ...Hydrogels electrolytes with flexibility and high conductivity have been widely used in kinds of flexible electronics.However,hydrogels always suffer from the inevitable freezing of water at subzero temperatures,which results in the sacrificing of their electrical properties.Herein,an anti-freezing,flexible hydrogel based on in situ reduction of graphene oxide(GO)and laponite has been developed as electrolyte for high performance supercapacitor and sensitive sensors.The crosslinked GO and laponite in polyacrylamide(PAM)resulted in an enhanced mechanical property,while the in-situ reduction of GO in the hydrogel enhanced the conductivity and diminishes the aggregated of GO.These features guarantee a reliable electro signal as sensor and a high performance of the supercapacitor.Besides,in the process of preparation of reduced graphene oxide(rGO)hydrogel,the addition of ethylene glycol(EG)and KOH,endows the hydrogel antifreeze properties.This anti-freezing electrolyte can be stretched to a strain of 1600%and maintained a specific capacitance of 37.38 F·g^(-1) at-20℃.In addition,the photothermal conversion character of rGO in the hydrogel,endows it’s the potential application in wound healing.The overall merits of the hydrogel will open up a new avenue for sensitive sensor and energy storage device in practical applications.展开更多
The inland lakes on the Tibetan Plateau(TP)are undergoing significant changes due to their sensitivity to climate.The largest lake in Tibet,Siling Co,has expanded most dramatically during recent decades.Using Landsat,...The inland lakes on the Tibetan Plateau(TP)are undergoing significant changes due to their sensitivity to climate.The largest lake in Tibet,Siling Co,has expanded most dramatically during recent decades.Using Landsat,GRACE and meteorological data,the expansion of Siling Co was detailed in four stages and the process was further explained.The results show that the lake area increased from 1647.30 km^(2)in 1972 to 2438.99 km^(2)in 2020.It experienced a slow growth at a rate 6.03 km^(2)/yr from 1972 to 1988,while fluctuating at 1.44 km^(2)/yr during 1989–1997,then accelerated at 60.28 km^(2)/yr between 1998 and 2005,and expanded slowly again at 11.40 km^(2)/yr since 2006.The continued expansion led to its merger with nearby Yagain Co in 2003.Terrestrial water storage(TWS)increase was also observed from GRACE(0.65 cm/yr),with about 0.75 coefficient of determination between the TWS and lake area during 2002–2020.The long-term expansion of Siling Co is related to the increasing trends of temperature and precipitation,but their contributions vary with time span.Specifically,the accelerated stage between 1998 and 2005 can be explained by the increased temperature and precipitation accompanied by a drop in evaporation,while the slow expansion since 2006 was due to the decrease in precipitation and temperature and the rise in evaporation.There is no obvious mass loss of glaciers revealed by GRACE during 2002–2020,which may be related to the negative trend of the temperature.Furthermore,the precipitation may still make a major contribution in this phase,as its average is about 93.9 mm higher than that in 1988–1997.展开更多
Cows mounting behavior is a significant manifestation of estrus in cows.The timely detection of cows mounting behavior can make cows conceive in time,thereby improving milk production of cows and economic benefits of ...Cows mounting behavior is a significant manifestation of estrus in cows.The timely detection of cows mounting behavior can make cows conceive in time,thereby improving milk production of cows and economic benefits of the pasture.Existing methods of mounting behavior detection are difficult to achieve precise detection under occlusion and severe scale change environments and meet real-time requirements.Therefore,this study proposed a Cow-YOLO model to detect cows mounting behavior.To meet the needs of real-time performance,YOLOv5s model is used as the baseline model.In order to solve the problem of difficult detection of cows mounting behavior in an occluded environment,the CSPDarknet53 of YOLOv5s is replaced with Non-local CSPDarknet53,which enables the network to obtain global information and improves the model’s ability to detect the mounting cows.Next,the neck of YOLOv5s is redesigned to Multiscale Neck,reinforcing the multi-scale feature fusion capability of model to solve difficulty detection under dramatic scale changes.Then,to further increase the detection accuracy,the Coordinate Attention Head is integrated into YOLOv5s.Finally,these improvements form a novel cow mounting detection model called Cow-YOLO and make Cow-YOLO more suitable for cows mounting behavior detection in occluded and drastic scale changes environments.Cow-YOLO achieved a precision of 99.7%,a recall of 99.5%,a mean average precision of 99.5%,and a detection speed of 156.3 f/s on the test set.Compared with existing detection methods of cows mounting behavior,Cow-YOLO achieved higher detection accuracy and faster detection speed in an occluded and drastic scale-change environment.Cow-YOLO can assist ranch breeders in achieving real-time monitoring of cows estrus,enhancing ranch economic efficiency.展开更多
Macroalgae that inhabit intertidal zones are exposed to the air for several hours during low tide and must endure desiccation and high variations in temperature, light intensity, and salinity. Pyropia yezoensis (Rhodo...Macroalgae that inhabit intertidal zones are exposed to the air for several hours during low tide and must endure desiccation and high variations in temperature, light intensity, and salinity. Pyropia yezoensis (Rhodophyta, Bangiales), a typical intertidal red macroalga that is commercially cultivated in the northwestern Pacific Ocean, was investigated under different dehydration stresses of desiccation, high salinity, and high mannitol concentration. Using chlorophyll fluorescence imaging, photosynthetic activities of P. yezoensis thalli were analyzed using six parameters derived from quenching curves and rapid light curves. A distinct discrepancy was revealed in photosynthetic responses to different dehydration stresses. Dehydration caused by exposure to air resulted in rapid decreases in photosynthetic activities, which were always lower than two other stresses at the same water loss (WL) level. High salinity only reduced photosynthesis significantly at its maximum WL of 40% but maintained a relatively stable maximum quantum yield of photosystem II (PSII) (Fv/Fm). High mannitol concentration induced maximum WL of 20% for a longer time (60 min) than the other two treatments and caused no adverse influences on the six parameters at different WL except for a significant decrease in non-photochemical quenching (NPQ) at 20% WL. Illustrated by chlorophyll fluorescence images, severe spatial heterogeneities were induced by desiccation with lower values in the upper parts than the middle or basal parts of the thalli. The NPQ and rETRmax (maximum relative electron transport rate) demonstrated clear distinctions for evaluating photosynthetic responses, indicating their sensitivity and applicability. The findings of this study indicated that the natural dehydration of exposure to air results in stronger and more heterogeneous effects than those of high salinity or high mannitol concentration.展开更多
Ready-to-eat wine-pickled mud snails(Bullacta exarata)typically host a large number of microorganisms and are frequently contaminated with pathogenic bacteria during processing,resulting in a higher risk for foodborne...Ready-to-eat wine-pickled mud snails(Bullacta exarata)typically host a large number of microorganisms and are frequently contaminated with pathogenic bacteria during processing,resulting in a higher risk for foodborne illness with consumption.In this study,the decontamination effects of different treatment methods,including the use of ultrasonic cleaning(USC),natural chemicals,and ultra-high pressure(UHP),on the quality and safety of pickled mud snails were investigated by assessing the total viable count(TVC),total volatile base nitrogen(TVB-N)content,thiobarbituric acid-reactive substance(TBARS),and pH value of the products after 12 months of storage at-20℃.Treatment with 200 W USC for 5 min was the most effective approach for reducing TVC in raw mud snails,with a minimal change in food quality.Natural chemical treatment or UHP treatment significantly inhibited the increase inTVC,pH,and TBARS and TVB-N accumulation compared with the control group;however,their combined treatment had no synergistic effect.In contrast,the combined chemical treatment was more effective in inhibiting changes in the above indices in pickled mud snails than UHP treatment alone or combined chemicals+UHP treatment.In addition,the bacterial diversity of pickled mud snails before and after 12 months of storage at-20℃was determined using lllumina MiSeq sequencing.Our results indicated that USC combined with natural chemicals can be utilized commercially to maintain the quality and safety of pickled mud snails during storage at-20℃.展开更多
The reasonable allocation of healthcare resources across different levels of healthcare facilities is the key to promoting the tiered diagnosis and treatment approach.The sudden outbreak of COVID−19 underscores the sh...The reasonable allocation of healthcare resources across different levels of healthcare facilities is the key to promoting the tiered diagnosis and treatment approach.The sudden outbreak of COVID−19 underscores the shortage of resources and service capability of China’s primary healthcare facilities.From the perspective of the vertical division of labor in the healthcare service system and based on the quality adjustment and quantitative correction of healthcare workers,this paper comprehensively calculates and analyzes the evenness of resources allocation between hospitals and primary healthcare facilities;and then,combining the theoretical model derivation with China’s empirical data test,this paper demonstrates how the misallocation of healthcare resources affects their utilization efficiency.The results are as below.(1)There are varying degrees of quantity and quality imbalance in various healthcare resources between hospitals and primary healthcare facilities.(2)When other conditions remain unchanged,the more misallocated healthcare resources are,the lower the“actual”utilization efficiency after quality adjustment is.(3)Compared with the absence of price regulation,government price regulation has led to a relative“overtreatment equilibrium”in the healthcare service market.Therefore,measures should be taken to optimize the structure of healthcare resources allocation and improve the efficiency of resources utilization,such as strengthening the government’s healthcare financing function,formulating policies that favor primary healthcare facilities,and encouraging social capital to invest at the community level.展开更多
基金financial support from the National Natural Science Foundation of China (NSFC,21875155,22032004)the support of the National Key Research and Development Program of China (2021YFA1201502)the support of the Nanqiang Young Top-notch Talent Fellowship in Xiamen University。
文摘The practical application of lithium-sulfur(Li-S)batteries is greatly hindered by soluble polysulfides shuttling and sluggish sulfur redox kinetics.Rational design of multifunctional hybrid materials with superior electronic conductivity and high electrocatalytic activity,e.g.,heterostructures,is a promising strategy to solve the above obstacles.Herein,a binary metal sulfide MnS-MoS_(2) heterojunction electrocatalyst is first designed for the construction of high-sulfur-loaded and durable Li-S batteries.The MnS-MoS_(2) p-n heterojunction shows a unique structure of MoS_(2) nanosheets decorated with ample MnS nanodots,which contributes to the formation of a strong built-in electric field at the two-phase interface.The MnS-MoS_(2) hybrid host shows strong soluble polysulfide affinity,enhanced electronic conductivity,and exceptional catalytic effect on sulfur reduction.Benefiting from the synergistic effect,the as-derived S/MnS-MoS_(2) cathode delivers a superb rate capability(643 m A h g^(-1)at 6 C)and a durable cyclability(0.048%decay per cycle over 1000 cycles).More impressively,an areal capacity of 9.9 m A h cm^(-2)can be achieved even under an extremely high sulfur loading of 14.7 mg cm^(-2)and a low electrolyte to sulfur ratio of 2.9μL mg^(-1).This work provides an in-depth understanding of the interfacial catalytic effect of binary metal compound heterojunctions on sulfur reaction kinetics.
基金The financial supports from the National Natural Science Foundation of China(22178014)。
文摘The concentration and velocity fields of two refractive index matched miscible shear-thinning fluids in a lid-driven cavity were investigated by using planar laser-induced fluorescence and particle image velocimetry,as well by computational fluid dynamics.Quantitative analyses show that the results obtained by flow simulations with the species transport model are in good agreement with the experimental results.The effects of different parameters were studied by using the intensity of segregation.For two fluids with the same rheological parameters,the relative amounts of liquids H_(1)/H and the power-law index n dominate the mixing process while the Reynolds number Re plays a marginal role.As for two fluids with density difference,buoyancy has significant influence on the mixing process.The dimensionless group Ar/Re(redefined such as to include shear thinning behavior)is proposed for assessing the effect of buoyancy and rheological properties on the mixing of miscible shear-thinning fluids.
基金Supported by the National Natural Science Foundation of China(Nos.42276148,41976133)。
文摘The economic alga Neopyropia,which holds significant value in China for its edibility and economic potential,harbors diverse epiphytic bacteria on its surface.The epiphytic bacteria on Neopyropia yezoensis and Neopyropia katadae,two nori species of Neopyropia living at the same tidal level but with distinct physiological states and living habits,were investigated to understand the differences between them and the effects of epiphytic bacteria on their differential characteristics.Analysis of 16S rRNA gene sequences and real-time quantitative PCR(qPCR)of thalli and seawater samples(n=24)revealed notable differences in microbial diversity and community structure between the two species.Bacteroidetes dominated the bacterial communities in association with N.yezoensis,whereas Proteobacteria were predominant in N.katadae.Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt2)analysis revealed enriched genes that related to the ABC transport system,iron complex outer membrane receptor proteins,and proliferation in N.yezoensis,whereas N.katadae exhibited enrichment of genes that related to energy supply as well as cell wall and cell membrane production.The results of qPCR indicate a higher abundance of epiphytic bacteria on surface of N.yezoensis than those on surface of N.katadae.The findings indicate that differences in the living environments of N.yezoensis and N.katadae may result in distinct structural composition and abundance of epiphytic bacteria on their surfaces,thereby conferring specific biological functionalities to each microbial community,and the epiphytic bacteria may shape the living habits of hosts to some extents.This study provided a basis for understanding the close association between surface microorganisms and algal bodies,and the physiological and ecological characteristics of nori species.
基金partially supported by the National Natural Science Foundation of China (grant no. 22021001, 22179111)the Ministry of Science and Technology of China (grant no. 2021YFA1201900)+3 种基金the Basic Research Program of Tan Kah Kee Innovation Laboratory (grant no. RD2021070401)the Principal Fund from Xiamen University (grant no. 20720210015)the Fundamental Research Funds for the Central Universities (grant no. 20720220010)the National Natural Science Foundation of China (grant no. 22202082)。
文摘As the rapid development of more powerful and safer lithiumion batteries, the mechanism study of gases evolution is attacking more and more attention in recent years. Especially under overcharge/discharge and/or high-temperature working condition.
文摘With less extra stress on the testing sample, a free-stress sample holder was designed to place the sample horizontally. With the free-stress sample holder, a magnetoelectric (ME) coefficient measurement system was developed based on dynamic method. This measurement system has the hardware part and the software part, integrated by the DC magnetic field generation module, the AC magnetic field generation module, the induced ME voltage detecting module and PC software module. Then, a sample of Terfenol-D/PZT/Terfenol-D trilayer was designed and fabricated, and the relationships of its ME coefficient influenced by the DC magnetic field and the frequency of the AC magnetic field were tested using the measurement system. And the results showed that the free-stress sample holder was proven to improve the accuracy of the measurement system by less stress interference.
文摘To the complication and uncertainty in coal seam floor water-inrush monitoring, Internet of Things (IoT) perception is applied to the monitoring and controlling of coal seam floor water inrush with major impacting factors analyzed, and an open distribution information processing platform is constructed based on IoT-GIS coupling perception. Then using the platform to comprehensively perceive various floor water inrush impacting parameters, an AHP model is established. At this stage, by means of weight reasoning algorithm based on dynamic Bayesian network, the AHP weight can be worked out using the two-way probability transfer and chain rules. Then the multiple factors are spatially fused by GIS to form a non-linear mathematical model for the calculation of the water inrush relative probability index. After that, the discrimination threshold of the comb graph for the floor water inrush relative probability index is used to further identify the floor water inrush mode. The experiments in 10# Coal Seam of Suntuan Mine show that, the accuracy perceived the floor water inrush is above 92%, and the platform of IoT-GIS coupling perception has the obvious technical advantage than traditional monitoring technology. Therefore, it has has demonstrated strong systematic robustness, important theoretical and application significance.
基金Supported by the National Key R&D Program of China(Nos.2018YFC1406704,2018YFD0900106,2018YFC1406700)the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2018SDKJ0302-4)the MOA Modern Agricultural Talents Support Project。
文摘Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway network in cluster of orthologous groups(COG)and Kyoto Encyclopedia of Genes and Genomes(KEGG),and carbohydrate-active enzymes(CAZymes)were explored in metagenomic analysis.DNA extraction from gametophytes of P.haitanensis was performed first,followed by library construction,sequencing,preprocessing of sequencing data,taxonomy assignment,gene prediction,and functional annotation.The results show that the predominant microorganisms of P.haitanensis were bacteria(98.98%),and the phylum with the highest abundance was Proteobacteria(54.64%),followed by Bacteroidetes(37.92%).Erythrobacter(3.98%)and Hyunsoonleella jejuensis(1.56%)were the genera and species with the highest abundance of bacteria,respectively.The COG annotation demonstrated that genes associated with microbial metabolism was the predominant category.The results of metabolic pathway annotation show that the ABC transport system and two-component system were the main pathways in the microbial community.Plant growth hormone biosynthesis pathway and multi-vitamin biosynthesis functional units(modules)were the other important pathways.The CAZyme annotation revealed that the starch might be an important carbon source for microorganisms.Glycosyl transferase family 2(GT2)and glycosyl transferase family 3(GT3)were the highly abundant families in glucoside transferase superfamily.Six metagenome-assembled genomes containing enzymes involved in the biosynthesis of cobalamin(vitamin B 12)and indole-3-acetic acid were obtained by binning method.They were confirmed to belong to Rhodobacterales and Rhizobiales,respectively.Our findings provide comprehensive insights into the microorganism community of Pyropia.
基金Supported by the National Key R&D Program of China(Nos.2018YFD0900106,2018YFC1406700)the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2018SDKJ0302-4)the MOA Modern Agricultural Talents Support Project。
文摘The genus Pyropia contains several important cultivated species.Genetic research in nori species has mainly focused on the cell nucleus,with few studies on organelles(chloroplast and mitochondria).Due to the high copy numbers of organelles in cells,which influence the development and traits of algae,it is necessary to study their genetic mechanism.In this study,the marine red alga Pyropia yezoensis,an important economic macroalga,was selected as the study object.To investigate organelle(chloroplast and mitochondria)inheritance in P.yezoensis,the wild type RZ(maternal strain)was crossed with the red mutant HT(paternal strain)and 30 color-sectors from 11 F1 gametophytic blades were examined.The complete chloroplast and mitochondrial genomes of the red mutant(HT)were assembled for the first time.One reliable and stable single nucleotide polymorphism(SNP)loci filtrated by bioinformatics analysis was used as a molecular marker for chloroplast and mitochondrial DNA,respectively,in subsequent experiments.PCR amplification and sequence analysis showed that the haplotypes of color-sectors detected were consistent with those of the maternal parent,confirming that both chloroplast and mitochondrial genomes were inherited maternally in P.yezoensis.The inheritance pattern of organelles in P.yezoensis can be used to guide the hybridization and breeding of nori.Additionally,the organelle SNP markers developed in this study can be applied in subsequent genetic research.
基金Supported by the National Natural Science Foundation of China(Nos.41976146,31672641)the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2018SDKJ0302-4)+1 种基金the National Key R&D Program of China(No.2018YFD0900106)the Shandong Province Key Research and Development Program(No.2019GHY112008)。
文摘Pyropia yezoensis is an important macroalga because of its extensive global distribution and economic importance.Color is an important trait in the thalli of P.yezoensis,it is also an effective marker to identify the hybridization in genetic breeding.In this study,a high-density genetic linkage map was constructed based on high-throughput single nucleotide polymorphism(SNP)markers,and used for analyzing the quantitative trait loci(QTLs)of red color trait in the thalli of P.yezoensis.The conchospore undergoes meiosis to develop into an ordered tetrad,and each cell has a haploid phenotype and can grow into a single individual.Based on this theory,F1 haploid population was used as the mapping population.The map included 531 SNP markers,394.57 cM long on average distance of 0.74 cM.Collinear analysis of the genetic linkage map and the physical map indicated that the coverage between the two maps was 79.42%.Furthermore,QTL mapping identified six QTLs for the chromosomal regions associated with the red color trait of the thalli.The value of phenotypic variance explained(PVE)by an individual QTL ranged from 4.71%-63.11%.And QTL qRed-1-1,with a PVE of 63.11%,was considered the major QTL.Thus,these data may provide a platform for gene and QTL fine mapping,and marker-assisted breeding in P.yezoensis in the future.
基金supported by the National Key R&D Program of China(No.2018YFA0209302)the National Natural Science Foundation of China(Nos.21976177,22276191).
文摘Hydrogels electrolytes with flexibility and high conductivity have been widely used in kinds of flexible electronics.However,hydrogels always suffer from the inevitable freezing of water at subzero temperatures,which results in the sacrificing of their electrical properties.Herein,an anti-freezing,flexible hydrogel based on in situ reduction of graphene oxide(GO)and laponite has been developed as electrolyte for high performance supercapacitor and sensitive sensors.The crosslinked GO and laponite in polyacrylamide(PAM)resulted in an enhanced mechanical property,while the in-situ reduction of GO in the hydrogel enhanced the conductivity and diminishes the aggregated of GO.These features guarantee a reliable electro signal as sensor and a high performance of the supercapacitor.Besides,in the process of preparation of reduced graphene oxide(rGO)hydrogel,the addition of ethylene glycol(EG)and KOH,endows the hydrogel antifreeze properties.This anti-freezing electrolyte can be stretched to a strain of 1600%and maintained a specific capacitance of 37.38 F·g^(-1) at-20℃.In addition,the photothermal conversion character of rGO in the hydrogel,endows it’s the potential application in wound healing.The overall merits of the hydrogel will open up a new avenue for sensitive sensor and energy storage device in practical applications.
基金supported by the National Natural Science Foundation of China(No.42076234).
文摘The inland lakes on the Tibetan Plateau(TP)are undergoing significant changes due to their sensitivity to climate.The largest lake in Tibet,Siling Co,has expanded most dramatically during recent decades.Using Landsat,GRACE and meteorological data,the expansion of Siling Co was detailed in four stages and the process was further explained.The results show that the lake area increased from 1647.30 km^(2)in 1972 to 2438.99 km^(2)in 2020.It experienced a slow growth at a rate 6.03 km^(2)/yr from 1972 to 1988,while fluctuating at 1.44 km^(2)/yr during 1989–1997,then accelerated at 60.28 km^(2)/yr between 1998 and 2005,and expanded slowly again at 11.40 km^(2)/yr since 2006.The continued expansion led to its merger with nearby Yagain Co in 2003.Terrestrial water storage(TWS)increase was also observed from GRACE(0.65 cm/yr),with about 0.75 coefficient of determination between the TWS and lake area during 2002–2020.The long-term expansion of Siling Co is related to the increasing trends of temperature and precipitation,but their contributions vary with time span.Specifically,the accelerated stage between 1998 and 2005 can be explained by the increased temperature and precipitation accompanied by a drop in evaporation,while the slow expansion since 2006 was due to the decrease in precipitation and temperature and the rise in evaporation.There is no obvious mass loss of glaciers revealed by GRACE during 2002–2020,which may be related to the negative trend of the temperature.Furthermore,the precipitation may still make a major contribution in this phase,as its average is about 93.9 mm higher than that in 1988–1997.
基金supported by the National Natural Science Foundation of China(Grant No.32072788,31902210,32002227,32172784)the National Key Research and Development Program of China(Grant No.2019YFE0125600)the earmarked fund(Grant No.CARS36).
文摘Cows mounting behavior is a significant manifestation of estrus in cows.The timely detection of cows mounting behavior can make cows conceive in time,thereby improving milk production of cows and economic benefits of the pasture.Existing methods of mounting behavior detection are difficult to achieve precise detection under occlusion and severe scale change environments and meet real-time requirements.Therefore,this study proposed a Cow-YOLO model to detect cows mounting behavior.To meet the needs of real-time performance,YOLOv5s model is used as the baseline model.In order to solve the problem of difficult detection of cows mounting behavior in an occluded environment,the CSPDarknet53 of YOLOv5s is replaced with Non-local CSPDarknet53,which enables the network to obtain global information and improves the model’s ability to detect the mounting cows.Next,the neck of YOLOv5s is redesigned to Multiscale Neck,reinforcing the multi-scale feature fusion capability of model to solve difficulty detection under dramatic scale changes.Then,to further increase the detection accuracy,the Coordinate Attention Head is integrated into YOLOv5s.Finally,these improvements form a novel cow mounting detection model called Cow-YOLO and make Cow-YOLO more suitable for cows mounting behavior detection in occluded and drastic scale changes environments.Cow-YOLO achieved a precision of 99.7%,a recall of 99.5%,a mean average precision of 99.5%,and a detection speed of 156.3 f/s on the test set.Compared with existing detection methods of cows mounting behavior,Cow-YOLO achieved higher detection accuracy and faster detection speed in an occluded and drastic scale-change environment.Cow-YOLO can assist ranch breeders in achieving real-time monitoring of cows estrus,enhancing ranch economic efficiency.
基金supported by National Key R&D Program of China(2018YFC1406704 and 2020YFD0900702).
文摘Macroalgae that inhabit intertidal zones are exposed to the air for several hours during low tide and must endure desiccation and high variations in temperature, light intensity, and salinity. Pyropia yezoensis (Rhodophyta, Bangiales), a typical intertidal red macroalga that is commercially cultivated in the northwestern Pacific Ocean, was investigated under different dehydration stresses of desiccation, high salinity, and high mannitol concentration. Using chlorophyll fluorescence imaging, photosynthetic activities of P. yezoensis thalli were analyzed using six parameters derived from quenching curves and rapid light curves. A distinct discrepancy was revealed in photosynthetic responses to different dehydration stresses. Dehydration caused by exposure to air resulted in rapid decreases in photosynthetic activities, which were always lower than two other stresses at the same water loss (WL) level. High salinity only reduced photosynthesis significantly at its maximum WL of 40% but maintained a relatively stable maximum quantum yield of photosystem II (PSII) (Fv/Fm). High mannitol concentration induced maximum WL of 20% for a longer time (60 min) than the other two treatments and caused no adverse influences on the six parameters at different WL except for a significant decrease in non-photochemical quenching (NPQ) at 20% WL. Illustrated by chlorophyll fluorescence images, severe spatial heterogeneities were induced by desiccation with lower values in the upper parts than the middle or basal parts of the thalli. The NPQ and rETRmax (maximum relative electron transport rate) demonstrated clear distinctions for evaluating photosynthetic responses, indicating their sensitivity and applicability. The findings of this study indicated that the natural dehydration of exposure to air results in stronger and more heterogeneous effects than those of high salinity or high mannitol concentration.
基金the Major Project of Agricultural in Ningbo(No.2017C110009),China.
文摘Ready-to-eat wine-pickled mud snails(Bullacta exarata)typically host a large number of microorganisms and are frequently contaminated with pathogenic bacteria during processing,resulting in a higher risk for foodborne illness with consumption.In this study,the decontamination effects of different treatment methods,including the use of ultrasonic cleaning(USC),natural chemicals,and ultra-high pressure(UHP),on the quality and safety of pickled mud snails were investigated by assessing the total viable count(TVC),total volatile base nitrogen(TVB-N)content,thiobarbituric acid-reactive substance(TBARS),and pH value of the products after 12 months of storage at-20℃.Treatment with 200 W USC for 5 min was the most effective approach for reducing TVC in raw mud snails,with a minimal change in food quality.Natural chemical treatment or UHP treatment significantly inhibited the increase inTVC,pH,and TBARS and TVB-N accumulation compared with the control group;however,their combined treatment had no synergistic effect.In contrast,the combined chemical treatment was more effective in inhibiting changes in the above indices in pickled mud snails than UHP treatment alone or combined chemicals+UHP treatment.In addition,the bacterial diversity of pickled mud snails before and after 12 months of storage at-20℃was determined using lllumina MiSeq sequencing.Our results indicated that USC combined with natural chemicals can be utilized commercially to maintain the quality and safety of pickled mud snails during storage at-20℃.
基金part of a major project of the National Social Science Fund“Research on the Theoretical System and Application of Government Supervision with Chinese Characteristics”(18ZDA111).
文摘The reasonable allocation of healthcare resources across different levels of healthcare facilities is the key to promoting the tiered diagnosis and treatment approach.The sudden outbreak of COVID−19 underscores the shortage of resources and service capability of China’s primary healthcare facilities.From the perspective of the vertical division of labor in the healthcare service system and based on the quality adjustment and quantitative correction of healthcare workers,this paper comprehensively calculates and analyzes the evenness of resources allocation between hospitals and primary healthcare facilities;and then,combining the theoretical model derivation with China’s empirical data test,this paper demonstrates how the misallocation of healthcare resources affects their utilization efficiency.The results are as below.(1)There are varying degrees of quantity and quality imbalance in various healthcare resources between hospitals and primary healthcare facilities.(2)When other conditions remain unchanged,the more misallocated healthcare resources are,the lower the“actual”utilization efficiency after quality adjustment is.(3)Compared with the absence of price regulation,government price regulation has led to a relative“overtreatment equilibrium”in the healthcare service market.Therefore,measures should be taken to optimize the structure of healthcare resources allocation and improve the efficiency of resources utilization,such as strengthening the government’s healthcare financing function,formulating policies that favor primary healthcare facilities,and encouraging social capital to invest at the community level.
