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Single-cell profiling of the pig cecum at various developmental stages
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作者 Yan-Yuan Xiao Qing Zhang +9 位作者 Fei Huang Lin Rao Tian-Xiong Yao Si-Yu Yang Lei Xie Xiao-Xiao Zou Li-Ping Cai Jia-Wen Yang Bin Yang Lu-Sheng Huang 《Zoological Research》 SCIE CSCD 2024年第1期55-68,共14页
The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding... The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity,functional heterogeneity,and their importance in intestinal tract development and disease.Although such profiling has been extensively conducted in humans and mice,the single-cell gene expression landscape of the pig cecum remains unexplored.Here,single-cell RNA sequencing was performed on 45572 cells obtained from seven cecal samples in pigs at four different developmental stages(days(D)30,42,150,and 730).Analysis revealed 12 major cell types and 38 subtypes,as well as their distinctive genes,transcription factors,and regulons,many of which were conserved in humans.An increase in the relative proportions of CD8^(+)T and Granzyme A(low expression)natural killer T cells(GZMA^(low)NKT)cells and a decrease in the relative proportions of epithelial stem cells,Tregs,RHEX^(+)T cells,and plasmacytoid dendritic cells(pDCs)were noted across the developmental stages.Moreover,the post-weaning period exhibited an up-regulation in mitochondrial genes,COX2 and ND2,as well as genes involved in immune activation in multiple cell types.Cell-cell crosstalk analysis indicated that IBP6^(+)fibroblasts were the main signal senders at D30,whereas IBP6^(−)fibroblasts assumed this role at the other stages.NKT cells established interactions with epithelial cells and IBP6^(+)fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs.This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages. 展开更多
关键词 Single-cell RNA-seq CECUM Bama Xiang pigs Various developmental stages Cellular heterogeneity
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The influence of different types of satisfaction on loyalty on C2C online shopping platform:From the perspective of sellers and the platform
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作者 Yanan Lu Qian Huang Yuting Wang 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第5期36-48,I0007,共14页
With the rise and development of major types of platforms,the competition for resources has become extremely fierce,and the market share of C2C platforms has been seriously threatened by the loss of resources.Therefor... With the rise and development of major types of platforms,the competition for resources has become extremely fierce,and the market share of C2C platforms has been seriously threatened by the loss of resources.Therefore,building and maintaining buyers’satisfaction and loyalty to C2C platforms is critical to the survival and sustainability of C2C platforms in China.However,the current knowledge on how platform satisfaction and loyalty are constructed in the C2C e-commerce environment is incomplete.In this study,seller-based satisfaction and platform-based satisfaction are constructed separately.We further distinguish seller-based transaction satisfaction into economic and social satisfaction and explore their antecedents and consequences.To test our research hypotheses,we conduct a survey and collect data from a real online market(Taobao website).The results show that seller-based transaction satisfaction positively affects platform-based overall satisfaction and loyalty,and that perceived product quality,perceived assurance,and perceived price fairness all have a significant effect on economic satisfaction,whereas perceived relationship quality and perceived empathy significantly influence social satisfaction.These findings help us understand the literature related to customer satisfaction in the context of C2C in China and provide inspiration for online sellers and platforms. 展开更多
关键词 transaction-specific satisfaction social and economic satisfaction various antecedents of satisfaction overall satisfaction C2C online shopping platform
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Multifunctional AlPO_(4)reconstructed LiMn_(2)O_(4)surface for electrochemical lithium extraction from brine
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作者 Jun Gu Linlin Chen +5 位作者 Xiaowei Li Guiling Luo Linjing Fan Yanhong Chao Haiyan Ji Wenshuai Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期410-421,I0010,共13页
LiMn_(2)O_(4)(LMO)electrochemical lithium-ion pump has gained widespread attention due to its green,high efficiency,and low energy consumption in selectively extracting lithium from brine.However,collapse of crystal s... LiMn_(2)O_(4)(LMO)electrochemical lithium-ion pump has gained widespread attention due to its green,high efficiency,and low energy consumption in selectively extracting lithium from brine.However,collapse of crystal structure and loss of lithium extraction capacity caused by Mn dissolution loss limits its industrialized application.Hence,a multifunctional coating was developed by depositing amorphous AlPO_(4)on the surface of LMO using sol-gel method.The characterization and electrochemical performance test provided insights into the mechanism of Li^(+)embedment and de-embedment and revealed that multifunctional AlPO_(4)can reconstruct the physical and chemical state of LMO surface to improve the interface hydrophilicity,promote the transport of Li^(+),strengthen cycle stability.Remarkably,after 20 cycles,the capacity retention rate of 0.5AP-LMO reached 93.6%with only 0.147%Mn dissolution loss.The average Li^(+)release capacity of 0.5AP-LMO//Ag system in simulated brine is 28.77 mg/(g h),which is 90.4%higher than LMO.Encouragingly,even in the more complex Zabuye real brine,0.5AP-LMO//Ag can still maintain excellent lithium extraction performance.These results indicate that the 0.5AP-LMO//Ag lithium-ion pump shows promising potential as a Li^(+)selective extraction system. 展开更多
关键词 LiMn_(2)O_(4) Multifunctional AlPO_(4)coating Li^(+)embedment and de-embedment mechanism Stability HYDROPHILICITY Various solution
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Measurement Uncertainty Analysis of the Rotary-scan Method for the Measurable Dimension of Cylindrical Workpieces
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作者 Jiali Zhao Liang Zhang +2 位作者 Dan Wu Bobo Shen Qiaolin Li 《Instrumentation》 2024年第1期10-17,共8页
The measurement uncertainty analysis is carried out to investigate the measurable dimensions of cylindrical workpieces by the rotary-scan method in this paper.Due to the difficult alignment of the workpiece with a dia... The measurement uncertainty analysis is carried out to investigate the measurable dimensions of cylindrical workpieces by the rotary-scan method in this paper.Due to the difficult alignment of the workpiece with a diameter of less than 3 mm by the rotary scan method,the measurement uncertainty of the cylindrical workpiece with a diameter of 3 mm and length of 50 mm which is measured by a roundness measuring machine,is evaluated according to GUM(Guide to the Expression of Uncertainty in Measurement)as an example.Since the uncertainty caused by the eccentricity of the measured workpiece is different with the dimension changing,the measurement uncertainty of cylindrical workpieces with other dimensions can be evaluated the same as the diameter of 3 mm but with different eccentricity.Measurement uncertainty caused by different eccentricities concerning the dimension of the measured cylindrical workpiece is set to simulate the evaluations.Compared to the target value of the measurement uncertainty of 0.1μm,the measurable dimensions of the cylindrical workpiece can be obtained.Experiments and analysis are presented to quantitatively evaluate the reliability of the rotary-scan method for the roundness measurement of cylindrical workpieces. 展开更多
关键词 measurement uncertainty rotary-scan cylindrical workpiece various dimensions
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Fluoridation routes,function mechanism and application of fluorinated/fluorine-doped nanocarbon-based materials for various batteries:A review
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作者 Weicui Liu Nanping Deng +5 位作者 Gang Wang Ruru Yu Xiaoxiao Wang Bowen Cheng Jingge Ju Weimin Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期363-393,I0011,共32页
With the popularity and widespread applications of electronics,higher demands are being placed on the performance of battery materials.Due to the large difference in electronegativity between fluorine and carbon atoms... With the popularity and widespread applications of electronics,higher demands are being placed on the performance of battery materials.Due to the large difference in electronegativity between fluorine and carbon atoms,doping fluorine atoms in nanocarbon-based materials is considered an effective way to improve the performance of used battery.However,there is still a blank in the systematic review of the mechanism and research progress of fluorine-doped nanostructured carbon materials in various batteries.In this review,the synthetic routes of fluorinated/fluorine-doped nanocarbon-based(CF_x)materials under different fluorine sources and the function mechanism of CF_x in various batteries are reviewed in detail.Subsequently,judging from the dependence between the structure and electrochemical performance of nanocarbon sources,the progress of CF_x based on different dimensions(0D–3D)for primary battery applications is reviewed and the balance between energy density and power density is critically discussed.In addition,the roles of CF_x materials in secondary batteries and their current applications in recent years are summarized in detail to illustrate the effect of introducing F atoms.Finally,we envisage the prospect of CF_x materials and offer some insights and recommendations to facilitate the further exploration of CF_x materials for various high-performance battery applications. 展开更多
关键词 Nanocarbon materials Fluorinated/fluorine-doped effect Function mechanism Various batteries
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Introduction to the Special Issue on Advances in Neutrosophic and Plithogenic Sets for Engineering and Sciences:Theory,Models,and Applications
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作者 S.A.Edalatpanah Florentin Smarandache 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期817-819,共3页
Recently,research on uncertainty modeling has been progressing rapidly,and many essential and breakthrough studies have already been done.There are various ways to handle these uncertainties,such as fuzzy and intuitio... Recently,research on uncertainty modeling has been progressing rapidly,and many essential and breakthrough studies have already been done.There are various ways to handle these uncertainties,such as fuzzy and intuitionistic fuzzy sets.Although these concepts can take incomplete information in various real-world issues,they cannot address all types of uncertainty,such as indeterminate and inconsistent information.The neutrosophic theory founded by Florentin Smarandache in 1998 constitutes a further generalization of fuzzy set,intuitionistic fuzzy set,picture fuzzy set,Pythagorean fuzzy set,spherical fuzzy set,etc.Since then,this logic has been applied in various science and engineering domains. 展开更多
关键词 uncertainty modeling various science engineering domains
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Rural Revitalization Planning under the Territorial Spatial Planning System
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作者 HU Hongxia LI Zhi 《Journal of Landscape Research》 2023年第4期50-52,56,共4页
With the rapid development of China’s social economy,village planning is increasingly important.Departments should fully draw up practical village plan“integrating various plans”.In the context of“rural revitaliza... With the rapid development of China’s social economy,village planning is increasingly important.Departments should fully draw up practical village plan“integrating various plans”.In the context of“rural revitalization”,how to better promote“rural revitalization”and realize the concept that“lucid waters and lush mountains are invaluable assets”is a difficult problem in front of everyone.After many years of pilot of“integrating various plans”,“five levels,three categories and four systems”have been formed,but the territorial spatial planning in the new era under the construction of ecological civilization still faces many problems and challenges.In this paper,the practical village planning of“integrating various plans”under the background of territorial spatial planning was analyzed,aiming to establish and improve a complete rural spatial system and provide an effective scheme for rural governance mechanism by analyzing and refining the key points of rural planning. 展开更多
关键词 Territorial spatial planning Village planning Rural revitalization Integrating various plans
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洛马公司的无人机 被引量:1
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作者 李文杰 《飞航导弹》 北大核心 2007年第1期34-37,共4页
重点介绍了最近洛马公司披露的其臭鼬工厂秘密研制的无人机,包括臭鼬、VARIOUS、猎手-杀手、无人型F-35以及猎鹰无人轰炸机,并简单回顾了洛马公司其它研制单位在无人机领域的研究成果。
关键词 无人机 洛马公司 臭鼬 VARIOUS 猎手-杀手
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Kinematic Analysis and Experimental Verification on the Locomotion of Gecko 被引量:7
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作者 Woochul Nam TaeWon Seo +3 位作者 Byungwook Kim DongsuJeon Kyu-Jin Cho Jongwon Kim 《Journal of Bionic Engineering》 SCIE EI CSCD 2009年第3期246-254,共9页
This paper presents a kinematic analysis of the locomotion of a gecko,and experimental verification of the kinematic model.Kinematic analysis is important for parameter design,dynamic analysis,and optimization in biom... This paper presents a kinematic analysis of the locomotion of a gecko,and experimental verification of the kinematic model.Kinematic analysis is important for parameter design,dynamic analysis,and optimization in biomimetic robot research. The proposed kinematic analysis can simulate,without iteration,the locomotion of gecko satisfying the constraint conditions that maintain the position of the contacted feet on the surface.So the method has an advantage for analyzing the climbing motion of the quadruped mechanism in a real time application.The kinematic model of a gecko consists of four legs based on 7-degrees of freedom spherical-revolute-spherical joints and two revolute joints in the waist.The motion of the kinematic model is simulated based on measurement data of each joint.The motion of the kinematic model simulates the investigated real gecko's motion by using the experimental results.The analysis solves the forward kinematics by considering the model as a combination of closed and open serial mechanisms under the condition that maintains the contact positions of the attached feet on the ground. The motions of each joint are validated by comparing with the experimental results.In addition to the measured gait,three other gaits are simulated based on the kinematic model.The maximum strides of each gait are calculated by workspace analysis.The result can be used in biomimetic robot design and motion planning. 展开更多
关键词 kinematic analysis locomotlon of gecko lizard gait simulation various gaits workspace analysis
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The Evolution of Organic Carbon in Chinese Mollisol Under Different Farming Systems: Validation and Prediction by Using Century Model 被引量:6
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作者 GAO Chong-sheng WANG Jian-guo ZHANG Xing-yi SUI Yue-yu 《Agricultural Sciences in China》 CAS CSCD 2008年第12期1490-1496,共7页
Soil organic carbon (SOC) is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processi... Soil organic carbon (SOC) is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processing and assorting concerning data, based on clarifying parameters of Century model need, combined with best use of recorded data of field management, observed data of long-term experiments, climate, soil, and biology, and achieved results from Hailun Agro-Ecological Experimental Station, Chinese Academy of Sciences. The results were showed as follows: Before reclamation, SOC content was around 58.00 g kg^-1, SOC content dropped quickly in early years, and then decreased slowly after reclamation. SOC content was around 34.00 g kg^-1 with a yearly average rate of 8.91‰ decrease before long-term experiments was established. After a long-term experiment, SOC would change under different farming systems. Shift farming system changed as follows: By 20-year model simulation, SOC content decreased from 34.03 to 30.19 g kg^-1, with a yearly average rate of 5.97‰; by 100-year model simulation, SOC content decreased to 24.31 g kg^-1, with a yearly average rate of 3.36‰. Organic farming system changed as follows: By 20-year model simulation, SOC content decreased slowly from 34.03 to 33.39 g kg^-1, with a yearly average rate of 0.95‰, 5‰ less than that of shift farming system; by 100-year model simulation, SOC content decreased to 32.21 g kg^-1, with a yearly average rate of 0.55‰. "Petroleum" farming system changed as follows: By 20-year model simulation, SOC content decreased from 34.03 to 32.88 g kg^-1, with a yearly average rate of 1.72‰, much more than that of organic farming system; by 100-year model simulation, SOC content decreased to 30.89 g kg^-1, with a yearly average rate of 0.96‰. Combined "petroleum"-organic farming system changed as follows: By 20-year model simulation, SOC content was increased slightly; by 100-year model simulation, SOC content increased from 34.03 to 34.41g kg^-1, with a yearly average rate of 0.11‰. The above results provided an optimal way for maintaining SOC in Chinese mollisol farmland: To increase, as much as possible within agro-ecosystem, soil organic matter returns such as crop stubble, crop litter, crop straw or stalk, and manure, besides applying chemical nitrogen and phosphorous, which increased system productivity and maintained SOC content as well. Also, the results provided a valuable methodology both for a study of CO2 sequestration capacity and for a target fertility determination in Chinese mollisol. 展开更多
关键词 Century model Chinese mollisol farmland soil organic carbon various farming systems PREDICTION
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Study of total phenol,flavonoids contents and phytochemical screening of various leaves crude extracts of locally grown Thymus vulgaris 被引量:2
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作者 Mohammad Amzad Hossain Khulood Ahmed Salim AL-Raqmi +2 位作者 Zawan Hamood AL-Mijizy Afaf Mohammed Weli Qasim Al-Riyami 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第9期705-710,共6页
Objective:To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol,flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al ... Objective:To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol,flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al Jabal Al Akhdar,Nizwa.Sultanate of Oman.Methods:The leave sample was extracted with methanol and evaporated.Then it was defatted with water and extracted with different polarities organic solvents with increasing polarities.The prepare hexane,chloroform,ethyl acetate,hutanol and methanol crude extracts were used for their evaluation of total phenol,flavonoids contents and phytochemical screening study.The established conventional metliods were used for quantitative determination of total phenol,flavonoids contents and phytochemical screening.Results:Phytochemical screening for various crude extracts were tested and shown positive result for flavonoids,saponins and steroids compounds.The result for total phenol content was the highest in hutanol and the lowest in methanol crude extract whereas the total flavonoids contents was the highest in methanol and the lowest hexane crude extract.Conclusions:The crude extracts from locally grown Thymus vulgaris showed high concentration of flavonoids and it could be used as antibiotics for different curable and uncurable diseases. 展开更多
关键词 THYMUS VULGARIS L. VARIOUS crude extracts PHYTOCHEMICAL screening SOXHLET EXTRACTOR Total phenol Flavonoids contents.
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A review on electronically conducting polymers for lithium-sulfur battery and lithium-selenium battery:Progress and prospects 被引量:3
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作者 Hengying Xiang Nanping Deng +5 位作者 Huijuan Zhao Xiaoxiao Wang Liying Wei Meng Wang Bowen Cheng Weimin Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期523-556,共34页
Lithium-sulfur(Li-S) batteries and lithium-selenium(Li-Se) batteries,as environmental protection energy storage systems with outstanding theoretical specific capacities and high energy densities,have become the hotspo... Lithium-sulfur(Li-S) batteries and lithium-selenium(Li-Se) batteries,as environmental protection energy storage systems with outstanding theoretical specific capacities and high energy densities,have become the hotspots of current researches.Besides,elemental S(Se) raw materials are widely sourced and their production costs are both low,which make them considered one of the new generations of high energy density electrochemical energy storage systems with the most potential for development.However,poor conductivity of elemental S/Se and the notorious "shuttle effect" of lithium polysulfides(polyselenides) severely hinder the commercialization of Li-S/Se batteries.Thanks to the excellent electrical conductivity and strong absorption of lithium polysulfide(polyselenide) about electronically conducting polymer,some of the above thorny problems have been effectively alleviated.The review presents the fundamental studies and current development trends of common electronically conducting polymers in various components of Li-S/Se batteries,which involves polyaniline(PANI) polypyrrole(PPy),and polythiophene(PTh) with its derivatives,e.g.polyethoxythiophene(PEDOT) and poly(3,4-ethylene dioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS).Finally,the review not only summarizes the research directions and challenges facing the application of electronically conducting polymers,but also looks forward to the development prospects of them,which will provide a way for the practical use of electronically conducting polymers in Li-S/Se batteries with outstanding electrochemical properties in the short run. 展开更多
关键词 Li-S/Se batteries Electronically conducting polymer Various battery components Suppressed"shuttle effect" Outstanding electrochemical properties
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Fabrication of High-Density Out-of-Plane Microneedle Arrays with Various Heights and Diverse Cross-Sectional Shapes 被引量:2
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作者 Hyeonhee Roh Young Jun Yoon +4 位作者 Jin Soo Park Dong-Hyun Kang Seung Min Kwak Byung Chul Lee Maesoon Im 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第2期60-78,共19页
Out-of-plane microneedle structures are widely used in various applications such as transcutaneous drug delivery and neural signal recording for brain machine interface.This work presents a novel but simple method to ... Out-of-plane microneedle structures are widely used in various applications such as transcutaneous drug delivery and neural signal recording for brain machine interface.This work presents a novel but simple method to fabricate high-density silicon(Si)microneedle arrays with various heights and diverse cross-sectional shapes depending on photomask pattern designs.The proposed fabrication method is composed of a single photolithography and two subsequent deep reactive ion etching(DRIE)steps.First,a photoresist layer was patterned on a Si substrate to define areas to be etched,which will eventually determine the final location and shape of each individual microneedle.Then,the 1st DRIE step created deep trenches with a highly anisotropic etching of the Si substrate.Subsequently,the photoresist was removed for more isotropic etching;the 2nd DRIE isolated and sharpened microneedles from the predefined trench structures.Depending on diverse photomask designs,the 2nd DRIE formed arrays of microneedles that have various height distributions,as well as diverse cross-sectional shapes across the substrate.With these simple steps,high-aspect ratio microneedles were created in the high density of up to 625 microneedles mm^(-2)on a Si wafer.Insertion tests showed a small force as low as~172μN/microneedle is required for microneedle arrays to penetrate the dura mater of a mouse brain.To demonstrate a feasibility of drug delivery application,we also implemented silk microneedle arrays using molding processes.The fabrication method of the present study is expected to be broadly applicable to create microneedle structures for drug delivery,neuroprosthetic devices,and so on. 展开更多
关键词 MICRONEEDLE Various heights Cross-sectional shapes Isotropic etch Deep reactive ion etching
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Uptake,Depuration and Subcellular Distribution of Cadmium in Various Tissues of Perna viridis 被引量:4
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作者 M. S. YANG S. T. CHIU AND M. H. WONG(Department of Biology and Center for Waste Recycling and Environmental Biotechnology, Hong Kong Baptist University, Kowloon Tong, Hong Kong) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1995年第2期176-185,共10页
Green-lipped mussels (Perna viridis) were collected from a local mariculture site and placed in pre-cleaned sea water tanks containing 0, 0.2, 0.5 and 1.3 μg/ml CdCl2. The level of Cd in the gill, viscera and gonad w... Green-lipped mussels (Perna viridis) were collected from a local mariculture site and placed in pre-cleaned sea water tanks containing 0, 0.2, 0.5 and 1.3 μg/ml CdCl2. The level of Cd in the gill, viscera and gonad was measured. The concentration of Cd in the 3 tissues increased linearly over 4 days' of exposure. The rate of uptake depends on the concentration of Cd in the water. In the 3 tissues studied, the maximum rate of uptake (Vmax) was highest in the gill (500μg/g dry weight/day), followed by viscera (100μg/g dry weight/day) and gonad (56.8 μg/g dry weight/day). The majority of the Cd taken up was bound to a fraction of the heat-stable proteins similar to metallothioneins. The rate of Cd depuration from the tissues was poor. There was no change in Cd concentration over 8 days' depuration in clean water 展开更多
关键词 In Uptake Depuration and Subcellular Distribution of Cadmium in Various Tissues of Perna viridis
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Cell signaling associated with internalization of 67 kDa laminin receptor (67LR) by soluble laminin and its implication for protection against neurodegenerative diseases 被引量:1
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作者 Rayudu Gopalakrishna Narayan R.Bhat +1 位作者 Sarah Zhou William J.Mack 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第9期1513-1514,共2页
Various isoforms of laminins are present in the basement membranes complexed with other structural proteins.In the central nervous system(CNS),they are primarily localized to the basement membranes of blood vessels an... Various isoforms of laminins are present in the basement membranes complexed with other structural proteins.In the central nervous system(CNS),they are primarily localized to the basement membranes of blood vessels and reactive astrocytes.Limited amounts of various laminin isoforms are also associated with neuronal cell bodies and axons,which are referred to as“neuronal”laminins(Yamamoto et al.,1988).They exist in a soluble form,free from other basement membrane proteins.Neurons either produce these soluble laminins or acquire them from astroglial cells.Laminin stimulates neuritogenesis and confers neuroprotection in vitro,but their exact role of these neuronal soluble laminins in the CNS is yet unknown. 展开更多
关键词 Various ISOFORMS BASEMENT membranes confers NEUROPROTECTION
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New progress and prospect of oilfields development technologies in China 被引量:6
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作者 YUAN Shiyi WANG Qiang 《Petroleum Exploration and Development》 2018年第4期698-711,共14页
As technologies advance in oilfield development, mature oilfields are able to keep sustainable production and complex oilfields difficult to produce in the past are put into production efficiently. In this work, new p... As technologies advance in oilfield development, mature oilfields are able to keep sustainable production and complex oilfields difficult to produce in the past are put into production efficiently. In this work, new progresses of main development technologies for medium-high permeability and high water cut, low permeability, heavy oil, complex faulted block and special lithology reservoirs in the past decade, especially those international achievements made in enhanced oil recovery, were summarized, the key problems and major challenges that different oilfields are facing were analyzed, and the development route and direction of three-generation technologies were proposed as "mature technology in industrialized application, key technology in pilot test and innovative technology for backup". The key research contents should focus on:(1) Fine water flooding and chemical flooding for mature oilfields, improving oil recovery after chemical flooding, and gas flooding for low permeability reservoirs must be researched and tested in field further.(2) Study on subversive technologies like nanometer smart flooding, in-situ upgrading and injection and production through the same well should be strengthened.(3) EOR technologies for low oil price, new fields(deep sea, deep layer, unconventional reservoirs etc.) and highly difficult conditions(the quaternary recovery after chemical flooding, tertiary recovery in ultra-low permeability reservoirs) should be stocked up in advance. The development cost must be lowered significantly through constant innovation in technology and reservoir management to realize sustainable development of oilfields. 展开更多
关键词 various OIL RESERVOIRS OILFIELD DEVELOPMENT enhanced OIL recovery main technology technological DEVELOPMENT
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Study on the Singlet and Triplet StateElectron Transfer between Hypocrellin A and Aromatic Amines in Solvents of Various Polarity 被引量:1
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作者 Min WENG ManHua ZHANG Tao SHEN(Institute of Photographic Chemistry, Academia Sinica, P.O.Box 772,Beijing 100101) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期924-927,共4页
In this paper, the singlet and triplet state electron transfer processes between hypocrellin A(HA) and aromatic amines in solvents of various polarity have been studied by fluorescence and time-resolved transient abso... In this paper, the singlet and triplet state electron transfer processes between hypocrellin A(HA) and aromatic amines in solvents of various polarity have been studied by fluorescence and time-resolved transient absorption spectra. The results show,in.polar solvent, the quenching of HA fluorescence by aromatic amines results in Stern-Volmer plot, the investigation of transient absorption indicated that triplet-state electron transfer process from 3HA to the ground-state of amines occured, and the wines of the singlet and triplet state electron transfer rate constant were calculated, however in weak polar solvent, only the triplet-triplet absorption of HA was observed. 展开更多
关键词 StateElectron TRANSFER TRIPLET Solvents VARIOUS HYPOCRELLIN
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Chemical vapor deposition growth behavior of graphene 被引量:1
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作者 Jie Wang Tengfei Fan +3 位作者 Jianchen Lu Xiaoming Cai Lei Gao Jinming Cai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第1期136-143,共8页
The optimized growth parameters of graphene with different morphologies,such as dendrites,rectangle,and hexagon,have been obtained by low-pressure chemical vapor deposition on polycrystalline copper substrates.The evo... The optimized growth parameters of graphene with different morphologies,such as dendrites,rectangle,and hexagon,have been obtained by low-pressure chemical vapor deposition on polycrystalline copper substrates.The evolution of fractal graphene,which grew on the polycrystalline copper substrate,has also been observed.When the equilibrium growth state of graphene is disrupted,its intrinsic hexagonal symmetry structure will change into a non-hexagonal symmetry structure.Then,we present a systematic and comprehensive study of the evolution of graphene with different morphologies grown on solid copper as a function of the volume ratio of methane to hydrogen in a controllable manner.Moreover,the phenomena of stitching snow-like graphene together and stacking graphene with different angles was also observed. 展开更多
关键词 GRAPHENE chemical vapor deposition various morphologies DENDRITES METHANE
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Mechanical properties evaluation for thin film/substrate material systems 被引量:1
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作者 Simon S.Wang Zhanwei Liu Christopher M.Harvey 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2018年第1期1-2,共2页
Thin film/substrate material systems have been widely used in various industries such as aerospace,automotive,marine and electronics.One example is thermal barrier coatings(TBCs):TBCs are extensively applied to metall... Thin film/substrate material systems have been widely used in various industries such as aerospace,automotive,marine and electronics.One example is thermal barrier coatings(TBCs):TBCs are extensively applied to metallic components on gas turbine engines in order to protect them from high and prolonged heat loads,and they play an essential role in the aircraft industry.Another example is laminated polymer matrix composites(PMCs),reinforced with fibers such as carbon,glass or aramid:These materials have been extensively employed in a variety of applications due to their superior properties and the improving ease and cost-effectiveness of fabricating them.The evaluation of mechanical properties for thin film/substrate material systems is imperative for more efficient use of these material systems and further improvements. 展开更多
关键词 TBCS PMCs VARIOUS INDUSTRIES
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A Controllable Synthetic Route for Preparing Graphene-Cu and Graphene-Cu_2O Nanocomposites Using Graphene Oxide-CuO as a Precursor 被引量:1
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作者 陈丽 朱俊武 +3 位作者 BI Huiping MENG Xiaoqian YAO Pengcheng HAN Qiaofeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第5期947-950,共4页
The development of convenient method to obtain graphene-based nanocomposites is a key issue for their application. Herein, we described a facile route for synthesizing graphene-Cu and graphene-Cu2 O nanocomposites usi... The development of convenient method to obtain graphene-based nanocomposites is a key issue for their application. Herein, we described a facile route for synthesizing graphene-Cu and graphene-Cu2 O nanocomposites using graphene oxide-Cu O as a precursor. Remarkably, the different nanocomposites could be formed just by varying the reaction temperature and time. This work provides a feasible route for the preparation of graphene-based nanocomposites with various constituents. 展开更多
关键词 graphene-based nanocomposites various constituents PRECURSOR
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