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Journal of Wuhan University of Technology(Materials Science) 2019年第1期34卷 207-215页

作者： YANG zhangqiang SI junhui School of Materials Science and Engineering Fuzhou University School of Materials Science and Engineering Fujian University of Technology Fujian Provincial Key Laboratory of Advanced Materials Processing and Application

Composite nanofiber membranes based on biodegradable poly(lactic acid)(PLA) and cellulose nanofibrils(CNF) were produced via electrospinning. The influence of CNF content on the morphology, thermal properties, and mechanical properties of PLA/CNF composite nanofiber membranes were characterized by field scanning electron microscopy(FE-SEM), differential scanning calorimetry(DSC), thermogravimetric analysis(TGA), and dynamic mechanical analysis(DMA), respectively. The results show that the PLA/CNF composite nanofibers with smooth, free-bead surface can be successfully fabricated with various CNF contents. The introduction of CNF is an effective approach to improve the crystalline ability, thermal stability and mechanical properties for PLA/CNF composite fibers. The Young's moduli and tensile strength of the PLA/CNF composite nanofiber reach 106.6 MPa and 2.7 MPa when the CNF content is 3%, respectively, which are one times higher and 1.5 times than those of pure PLA nanofiber. Additionally, the water contact angle of PLA/CNF composite nanofiber membranes decreases with the increase of the CNF loading, resulting in the enhancement of their hydrophilicity.

关键词： poly(lactic acid)(PLA) cellulose nanofibrils(CNF) electrospinning mechanical and thermal properties

Desorption hysteresis of coalbed methane and its controlling factors: a brief review

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Frontiers of Earth Science 2021年第2期15卷 224-236页

作者： Weikai XU junhui LI Xiang WU Du LIU zhuangsen WANG College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China China Coalbed Methane Co.Ltd Beijing 100011China

Most coal reservoirs show high gas content with relatively low desorption efficiency,which restricts the efficiency of coalbed methane(CBM)extraction and single-well *** review highlights the desorption hysteresis mechanism and its controlling factors as well as methods and models to reveal desorption hysteresis and potential *** adsorption and desorption can be recorded by both gravimetric and volumetric *** different adsorption models are used,desorption is generally considered with the Langmuir *** hysteresis is influenced by the petrophysical composition,thermal maturity,pore structure distribution of the coal,reservoir temperature,and moisture and water *** for calculating desorption hysteresis include the area index,hysteresis index and introduction of a hysteresis factor and a hysteresis *** dynamics simulations of methane desorption are mainly based on theories of kinetics,thermodynamics,and potential *** interaction forces operating among coal,water,and methane molecules can be calculated from microscopic intermolecular forces(van der Waals forces).The desorption hysteresis mechanism and desorption process still lack quantitative probe methodologies,and future research should focus on coal wettability under the constraints of liquid content,potential energy adjustment mechanism,and quantitative analysis of methane desorption *** research is expected to reveal the desorption kinetics of methane through the use of the solid–liquid–gas three-phase coupling theory associated with the quantitative analysis of methane desorption hysteresis,thereby enhancing the recovery rate and efficiency of CBM wells.

关键词： desorption hysteresis diffusion process kinetics multiphase coupling coalbed methane production

Fabrication,microstructures,and properties of copper matrix composites reinforced by molybdenum-coated carbon nanotubes

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Rare Metals 2011年第4期30卷 401-407页

作者： NIE junhui JIA Chengchang JIA Xian zHANG Yafeng SHI Na LI Yi School of Matertals Sctence and Engmeermg Umverszty of Sctence and Technology Beijing Beijing 100083 China China Iron ＆ Steel Research Institute Group Beijing 100081 China

Multiwalled carbon nanotubes （CNTs） were coated by a molybdenum layer using carbonyl thermal decomposition process with a precursor of molybdenum hexacarbonyl. The Mo-coated CNTs （Mo-CNTs） were added into copper powders to fabricate Mo-CNT/Cu composites by means of mechanical milling followed by spark plasma sintering. The Mo-CNTs were uniform dispersion in the Cu matrix when their contents were 2.5 vo1.%-7.5 vol.%, while some Mo-CNT clusters were clearly observed at additions of 10.0 vo1.%-15.0 vol.% Mo-CNTs in the mixture. The mechanical, electrical, and thermal properties of the Mo-CNT/Cu composites were characterized, and the results showed that the tensile strength and hardness were 2.0 and 2.2 times higher than those of CNT-free specimens, respectively. Moreover, the Mo-CNT/Cu composites exhibited an enhanced thermal conductivity but inferior electrical conductivity compared with sintered pure Cu. The uncoated CNT/Cu composites were fabricated by the similar processes, and the measured tensile strength, hardness, thermal conductivity, and electrical conductivity of the CNT/Cu composites were lower than those of the Mo-CNT/Cu composites.

关键词： metallic matrix composites mechanical properties ball milling molybdenum carbon nanotubes

Using citizen science data to improve regional bird species list:A case study in Shaanxi,China

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Avian Research 2022年第3期13卷 341-346页

作者： Ying Ding Lichuan Xiong Fandi Ji junhui Lu Xiaojia zhu Huateng Huang College of Life Sciences Shaanxi Normal UniversityXi'an710119China

An accurate and updated regional bird species checklist is the foundation for biodiversity research and ***,with ongoing climate and landscape changes,tracking the distributions of bird species is challenging,and expert-curated species lists are often limited regarding survey area and *** in China is becoming increasingly popular,and observations recorded by citizen birders are quickly increasing as *** the value of these data for improving regional species lists and studying bird distribution needs a detailed and quantitative comparison of citizen science data and expert-curated *** collected observation reports from the China Bird Report Center,the largest online open platform for sharing bird sightings in *** focused on reports from 2016 to 2019 in Shaanxi *** expert-curated species lists,we used three sources:the latest bird field guide published by local ornithologists,the province list from Avibase,and a list generated from overlaying distribution range from BirdLife International with the outline of Shaanxi *** addition,we also compared the bird sighting coordinates with the species distribution maps from BirdLife ***,species checklists from different sources have considerable discrepancies,even among lists based on expert *** birdwatching data,there are 616 bird species in total,but less than half of the species(294)appear in all checklists,and 17.2%of species are unique to one *** hundred sixty-three species lack birdwatching records,but birdwatching identified 39 species new to the *** hundred thirty-six bird species have sighting locations outside the distribution ranges from BirdLife International,suggesting that updates might be *** data also showed a clear trend of bird species shifting to higher latitudes than their traditional *** being inadequate for generating a regional species checklist on its own,b

关键词： Bird distribution Birdwatching Citizen science Expert knowledge Species checklist

基于密度泛函理论下H_(2)S在单原子催化剂V/Ti_(2)CO_(2)上的分解机理研究

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物理化学学报 2021年第8期37卷 65-73页

作者：周君慧敖志敏安太成广东工业大学环境健康与污染控制研究院环境科学与工程学院广东省环境催化与健康风险控制重点实验室和广州市环境催化与污染控制重点实验室广州510006

解析工业脱硫气中硫化氢与催化剂的相互作用机制及其分解机理对于开发处理H_(2)S气体的催化剂具有重要意义。本研究采用密度泛函理论计算方法研究了H_(2)S分子在单原子催化剂(SACs,Ti和V原子负载的单层MXene-Ti_(2)CO_(2))表面上的吸附... 详细信息

解析工业脱硫气中硫化氢与催化剂的相互作用机制及其分解机理对于开发处理H_(2)S气体的催化剂具有重要意义。本研究采用密度泛函理论计算方法研究了H_(2)S分子在单原子催化剂(SACs,Ti和V原子负载的单层MXene-Ti_(2)CO_(2))表面上的吸附和催化解离行为。分波态密度(PDOS)、电荷分析以及差分电荷密度的结果表明:单原子Ti和V的负载导致了Ti_(2)CO_(2)表面上的电荷进行重新分配,并且显著改善了H_(2)S分子与Ti_(2)CO_(2)之间的相互作用,从而提高SACs的催化活性。为了深入理解硫化氢分子的催化处理过程及其分解机理(H_(2)S→HS^(*)+H^(*)→H2+S^(*)),本研究对硫化氢分子在Ti/Ti_(2)CO_(2)和V/Ti_(2)CO_(2)表面上的分解反应路径进行了对比分析。结果表明:硫化氢分子在被Ti和V负载的Ti_(2)CO_(2)表面上都能够自动解离形成-HS基团和一个质子(HS^(*)/H^(*)),而且在V负载的Ti_(2)CO_(2)的SACs上,整条路径的速率限制步骤所要跨越的能垒低至0.28 eV,该结果表明H_(2)S分子可在室温下能容易地被单原子催化剂V/Ti_(2)CO_(2)解离成H2分子和S原子,而且S原子能够在该催化剂表面团聚形成稳定的单质硫,从而完成催化循环。此外,使用该SACs催化剂分解H_(2)S,相比于已经报道过的其它体系的催化剂,无论是在可持续经济角度还是处理能力方面都有较好的应用前景。综上所述,我们发现V负载的Ti_(2)CO_(2)催化剂能够高效催化分解硫化氢气体。

关键词： MXene 单原子催化剂硫化氢解离 Ti_(2)CO_(2) 密度泛函理论

Selective Targeting of Perirhinal Cortex Projection to Hippocampal CA1 Interneurons

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Neuroscience Bulletin 2019年第4期35卷 763-765页

作者： Xiang Li Yiding Li junhui zhang Xiaohui zhang State Key Laboratory of Cognitive Neuroscience & Learning IDG/McGovern Institute for Brain Research Beijing Normal University Beijing 100875 China Department of Joint Surgery The 6th Hospital of Ningbo Ningbo 31500 China

Dear Editor,The perirhinal cortex (PER) is conceptually important in the recognition memory, especially in familiarity discrimination, whereas the hippocampus is important for association and recollection [1]. This no... 详细信息

关键词： Selective Targeting Perirhinal Cortex CA1 Interneurons

Transformation toughening in zirconium tantalum ceramics

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Science China(Technological Sciences) 2022年第8期65卷 1772-1779页

作者： LI Cong TAN Dan LUO Cheng LUO junhui Cao Ke YANG Li zHOU YiChun School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710126China Frontier Research Center of Thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710126China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China

Toughness enhancement of zirconium tantalum ceramics is conducive to the new generation of thermal barrier coatings(TBCs).The phase transformation toughening mechanism of zirconium tantalum ceramics has been explored through the Vickers indentation of YTao_(4) ceramic block,the phase transformation region is found near the indentation and the microcrack *** increased energy of stable phaseΔE_(M.M′)>0,and the volume expandedΔV≈1.9%,so,the phase transformation is a process of energy *** additional stressσa restraining the crack propagation was generated in the shielding area at the crack *** addition,combined with the toughening of ferroelastic domains switch,the traditional microcrack toughening,and crack propagation toughening,we summarized the toughening mechanism of YTao_(4) ceramics with the increasing external load,which is followed by ferroelastic toughening,phase transformation,microcrack,and crack *** the perspective of toughening,we found that z^(4+) doping in YTao_(4) ceramics could broaden the phase transformation range in phase transformation toughening,significantly improve the toughness and reduce the generation of cracks in microcrack toughening and crack propagation ***,toughening mechanism of zirconium tantalum ceramics has important guiding significance for the service of TBCs.

关键词： transformation toughening crack tip YTao_(4)ceramics toughening mode

高疏水纳米纤维素-壳聚糖/膨润土气凝胶的构建及其高效油水分离的应用

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复合材料学报 2024年第3期41卷 1347-1355页

作者：徐诗琪周洲汤睿江露莹王俊辉金学群张菁玮廖丹葵童张法张寒冰广西大学资源环境与材料学院南宁530004 崇左南方水泥有限公司广西钙基材料协同创新中心崇左532200 广西大学化学化工学院广西钙基材料协同创新中心南宁530004

气凝胶具有高孔隙率和高吸附性的特点,因此在含油废水处理领域是一种具有前景的候选材料。目前,所报道的气凝胶仍存在机械强度不足、制作工艺复杂、制备成本高等问题,限制了气凝胶在油水分离领域的应用。膨润土(Bentonite,BT)具有价格... 详细信息

气凝胶具有高孔隙率和高吸附性的特点,因此在含油废水处理领域是一种具有前景的候选材料。目前,所报道的气凝胶仍存在机械强度不足、制作工艺复杂、制备成本高等问题,限制了气凝胶在油水分离领域的应用。膨润土(Bentonite,BT)具有价格低、来源丰富、机械性能优良等特点,能够有效地改善气凝胶的机械性能。本文通过简单的冷冻干燥-常温浸渍法,在羧基纤维素纳米纤维(Carboxycellulose nanofibres,CNF-C)与壳聚糖(Chitosan,CS)的交联网络上引入剥离膨润土(Exfoliated bentonite,BTex),合成了疏水的纳米纤维素-壳聚糖/剥离膨润土气凝胶(CNC/BTex)。制备出的CNC/BTex气凝胶表现出优异的疏水性能(水接触角高达133°);经过挤压后在5 s内可恢复形变,具有良好的力学性能;对不同油品(正己烷、环己烷、二氯甲烷、食用油和发动机油)的吸附容量为18.48~40.20 g·g^(-1)不等。以二氯甲烷和环己烷为主要研究对象,经过5次循环使用后依然保持稳定的吸油性能(维持在原始吸附量的90%)。本文的工作为制备低成本、高性能的油水分离吸附材料提供了参考。

关键词：油水分离气凝胶纤维素壳聚糖剥离膨润土

Fabrication and Characterization of 3D Graded PDMS Scaffolds Using Vacuum-Assisted Resin Transfer Moulding

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Journal of Wuhan University of Technology(Materials Science) 2018年第5期33卷 1263-1270页

作者： SI junhui LIN Jiahe zHENG zifeng CUI zhixiang WANG Qianting School of Materials Science and Engineering Fujian University of TechnologyFuzhou 350118China Fujian Provincial Key Laboratory of Advanced Materials Processing and Application Fuzhou 350118China

Graded porous scaffold can be applied to study the interactions between cells and scaffold with different pore sizes. Polydimethylsiloxane（PDMS） scaffold with an axial pore size grade was successfully manufactured via vacuum-assisted resin transfer moulding（VARTM） and particle leaching technologies. The properties of graded PDMS scaffolds, including porosity, water absorption, interconnectivity, compression modulus, as well as compression strength were investigated. The results showed that the smaller the size of the NaCl particles is, the higher the porosity and water absorption of graded PDMS scaffolds would be. The graded PDMS scaffold fabricated had a compressive modulus and a compressive strength of 19.69±1.42 kPa and 4.76±0.22 kPa, respectively. Moreover, the graded chitosan（CS）-coated PDMS scaffolds were prepared by using dip-coating technique under low vacuum and their hydrophilicity was examined. It is found that the water contact angle（WCA） will decrease with an increase in the CS solution concentration and the coating time, which indicates that CS-coated PDMS scaffolds exhibit noticeable hydrophilicity compared with graded PDMS scaffold.

关键词： polydimethylsiloxane(PDMS) graded porous scaffold biomedical applications

铁酸镍负载杉木屑生物炭活化过一硫酸盐降解磷酸氯喹

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复合材料学报 2024年第8期41卷 4310-4323页

作者：王俊辉张菁玮孙静鄢经缘徐梓淞江露莹黄燕韩彪张寒冰郝格日乐何思静朱华凤广西大学资源环境与材料学院南宁530004 广西壮族自治区环境保护科学研究院南宁530022 广西大学化学化工学院广西石化资源加工及过程强化技术重点实验室南宁530004 广西大学广西新污染物监测预警与环境健康评估重点实验室南宁530004

近年来,磷酸氯喹(Chloroquine phosphate,CQP)作为治疗新冠的特效药得到广泛应用,并且由于其具有优异的抗炎症和抗疟疾能力,在疫情结束后仍发挥着重要作用。磷酸氯喹的大量使用对环境造成严重的潜在危害。将废弃的木屑资源化利用,通过... 详细信息

近年来,磷酸氯喹(Chloroquine phosphate,CQP)作为治疗新冠的特效药得到广泛应用,并且由于其具有优异的抗炎症和抗疟疾能力,在疫情结束后仍发挥着重要作用。磷酸氯喹的大量使用对环境造成严重的潜在危害。将废弃的木屑资源化利用,通过共沉淀-无氧煅烧法制备出具有磁回收能力的铁酸镍负载杉木屑生物炭复合材料(Nickel ferrate loaded biochar,NiFe_(2)O_(4)@BC),并研究其活化过一硫酸盐(Peroxymonosulfate,PMS)降解CQP的性能。利用多种表征对NiFe_(2)O_(4)@BC复合材料的组成结构、表面官能团和石墨化程度进行分析,相较于未改性的杉木屑生物炭(Fir sawdust biochar,BC),将具有磁性NiFe_(2)O_(4)的负载在生物炭上,使复合材料的石墨化程度提高,缺陷活性位点也得到增多,对CQP的去除效果得到巨大提高。主要考察了NiFe_(2)O_(4)@BC投加量、PMS浓度、溶液初始pH、共存无机阴离子与腐殖酸在降解CQP过程中的影响。研究表明:当Ni Fe_(2)O_(4)@BC投加量为0.5 g/L,PMS浓度为1.0 mmol/L,CQP浓度为10 mg/L的条件下,CQP去除率在120 min达到89%。在偏酸性或者偏碱的条件下更有利于CQP的降解,腐殖酸(Humic acid,HA)对NiFe_(2)O_(4)@BC活化PMS降解CQP具有促进作用。淬灭实验证实,自由基途径和非自由基途径生成的·OH与^(1)O_(2)主导了NiFe_(2)O_(4)@BC/PMS体系对CQP的降解。在同等条件下,对多种污染物均能达到80%以上的降解效果。此外,NiFe_(2)O_(4)@BC循环使用5次后,活化PMS去除CQP的效率仍能达到74%左右。本文为废弃杉木屑高效、绿色的资源化利用提供了新策略和借鉴意义。

关键词：生物炭降解木屑铁酸镍磷酸氯喹过一硫酸盐