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Surface Modification of Rice Husk Ash by Ethanol-assisted Milling to Reinforce the Properties of Natural Rubber/Butadiene Rubber Composites

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Chemical Research in Chinese Universities 2021年第3期37卷 757-762页

作者： CHEN Zhixiao QIAN Miaomiao LIU Chang XUE Beichen YULiyun zhu yanchao WANG Xiaofeng State Key Laboratory of Inorganic Synthesis&Preparative Chemistry College of ChemistryJilin UniversityChangchun130012P.R.China Jilin Province Product Quality Supervision Test Institute Changchun130103P.R.China

Rice husk ash(RHA),obtained by pyrolysis of rice husks,can be used as a potential reinforcing filler for rubber composites.In this work,ball milling in ethanol(ethanol-assisted milling)was used to hydroxylate the surface of RHA,promoting the graft modification of bis-(γ-triethoxysilylpropyl)-tetrasulfide(Si69).The obtained modified RHA(RHA-EM-Si69)was filled into the natural rubber/butadiene rubber(NR/BR)composites,and the filler-rubber interactions were enhanced.In consequence,RHA-EM-Si69 filled NR/BR composites showed overall improvement in the mechanical properties compared with RHA filled NR/BR composites.The tear strength increased from 13.37 kN/m to 34.71 kN/m,and the tensile strength increased from 1.84 MPa to 7.75 MPa.Carbon black(N774)was also used for comparison under the same conditions.This method provides a potential for promoting the value of RHA in rubber industry.

关键词： Ethanol-assisted milling Rice husk ash Rubber reinforcement

2000-2021年降水对黄河流域植被和地表水的影响

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Journal of Geographical Sciences 2024年第4期34卷 633-653页

作者：时晓蕊杨鹏夏军张永勇黄河清朱艳超 Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China National Engineering Research Center for Geographic Information System China University of GeosciencesWuhan 430074China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

The Yellow River Basin (YRB) is a vital ecological zone in China owing to its sensitive and fragile environment.Under the long-term influence of climate changes and artificial factors,the relationship between precipitation,vegetation,and surface water in the YRB has changed drastically,ultimately affecting the water resources and environmental management.Therefore,we applied multivariate statistical analysis to investigate the precipitation,normalized difference vegetation index (NDVI),and surface water changes in the YRB from 2000to 2021.Furthermore,we attempted to clarify the ecological effects of precipitation by explaining the relationship between precipitation and vegetation in terms of the time-lag relationship using the Integrated Multi-satellite Retrievals for Global Precipitation Measurement algorithm,Moderate Resolution Imaging Spectroradiometer,and hydrological databases.Precipitation,vegetation,and area of surface water in the YRB showed increasing trends from 2000–2021 (e.g.,7.215 mm/yr,0.004 NDVI/yr,and 0.932 km^(2)/yr,respectively).The water level in the upper reaches of the YRB showed a downward trend,whereas that in the middle and lower reaches exhibited an upward trend.Changes in precipitation had a positive effect on vegetation and surface water in the YRB,with correlation coefficients of 0.63 and0.51,respectively.The responses of NDVI and surface water elevation to precipitation were heterogeneous and delayed,with the majority showing a lag time of approximately≤16 days.Moreover,the lag times of Longyangxia Lake and Ngoring-Co Lake were 0 and 8 days,respectively.We showed that precipitation variability can effectively explain vegetation improvement and increases in surface water elevation,while providing a proven scenario for predicting the surface water and vegetation productivity under the influence of climate change.

关键词： precipitation vegetation cover surface water spatial and temporal variation Yellow River Basin

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共轭聚合物“电子舌”检测四环素类抗生素

华东理工大学学报（自然科学版） 2024年第3期50卷 354-359页

作者：陈世勇王杰朱琰超张丽娟王贵友胡爱国华东理工大学材料科学与工程学院上海市先进聚合物材料重点实验室上海200237

通过将6种共轭聚合物(CPs)与水性聚氨酯(WPU)物理共混,制备了WPU包覆的荧光传感阵列,用以检测水中的四环素类抗生素(TCs)。WPU与CPs共混后制备的薄膜阵列形状规则,荧光亮度高且稳定。WPU基体在溶胀后,存在泡孔状的孔道结构,增大了附着... 详细信息

通过将6种共轭聚合物(CPs)与水性聚氨酯(WPU)物理共混,制备了WPU包覆的荧光传感阵列,用以检测水中的四环素类抗生素(TCs)。WPU与CPs共混后制备的薄膜阵列形状规则,荧光亮度高且稳定。WPU基体在溶胀后,存在泡孔状的孔道结构,增大了附着于其中的CPs与水中待测物TCs的接触概率,增强了阵列的荧光响应。通过相机捕捉检测前后的荧光照片,并提取照片的红绿蓝(RGB)值,获得了18维向量数据库。通过主成分分析(PCA)和线性判别分析(LDA)等方法对数据进行降维处理。结果发现该荧光传感阵列具有良好的区分不同结构TCs的能力,LDA模型的分析预测准确度可达100%。这种WPU包覆CPs的荧光检测阵列具有制备便捷、成本低和稳定性好等优点,可望作为环境检测中的“电子舌”,检测并甄别水体中的污染物如四环素类抗生素。

关键词：共轭聚合物水性聚氨酯荧光传感阵列四环素类抗生素环境监测

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新工科背景下材料科学与工程本科创新应用型实践教学体系优化探索

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创新创业理论研究与实践 2024年第12期7卷 18-21页

作者：胡攀朱艳超祁亚军田键胡唐辉湖北大学材料科学与工程学院

材料科学与工程专业最典型的特点是材料学基础理论和工程实践紧密结合。实践教学体系是锻炼和培养学生工程素质、实践能力、创新素质的重要环节和途径。该文分析材料科学与工程专业本科实践教学体系现状及存在的问题，从实验教学课程体... 详细信息

材料科学与工程专业最典型的特点是材料学基础理论和工程实践紧密结合。实践教学体系是锻炼和培养学生工程素质、实践能力、创新素质的重要环节和途径。该文分析材料科学与工程专业本科实践教学体系现状及存在的问题，从实验教学课程体系、实习过程、毕业论文模式、实践教学管理考核体系4个方面提出具体改革建议，为培养新时期创新应用型材料学人才提供新思路。

关键词：新工科材料科学与工程创新应用型实践教学体系人才培养

碳化硅晶圆高温磁控溅射制备铝薄膜异常结晶现象

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微纳电子技术 2024年第5期61卷 157-161页

作者：王川宝默江辉朱延超王帅张力江付兴中中国电子科技集团公司第十三研究所石家庄050051 河北博威集成电路有限公司石家庄050200

在碳化硅表面使用高温磁控溅射法制备铝薄膜过程中有时会出现异常“斑点”现象,针对出现该异常现象可能的原因进行了研究,确认其主要因素为溅射温度和溅射功率,SiC表面状态和金属体系对异常现象的出现影响很小。采用白光干涉仪测定正常... 详细信息

在碳化硅表面使用高温磁控溅射法制备铝薄膜过程中有时会出现异常“斑点”现象,针对出现该异常现象可能的原因进行了研究,确认其主要因素为溅射温度和溅射功率,SiC表面状态和金属体系对异常现象的出现影响很小。采用白光干涉仪测定正常和异常区域表面形貌和粗糙度,结果表明“斑点”区域粗糙度明显低于正常区域,两者分别为1.7和5.6 nm。采用聚焦离子束分析技术对比剖面结构差异,发现“斑点”区域存在明显晶粒合并现象,金属表面晶界比正常区域少很多。“斑点”形成的可能原因是沉积过程温度过高,导致Al膜沉积初始成核过程中大量晶核合并、晶界消失,从而表面粗糙度显著降低。

关键词： SiC晶圆铝薄膜磁控溅射异常结晶溅射温度

Leaching kinetics of fluorine during the aluminum removal from spent Li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie Li Jianxin zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and Lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent Li-ion battery cathode materials.In this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent Li-ion batteries(LIBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery process.The mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this study.The leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/mol.While,the leaching of F was attributed to the dissolution of LiPF6and decomposition of PVDF,and the kinetics associated was described by Avrami model.The interaction of Al and F is advantageous to realize the defluoridation to some degree.It is expected that our investigation will provide theoretical support for the large-scale recycling of spent LIBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

Electron beam lithography on nonplanar and irregular surfaces

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Microsystems & Nanoengineering 2024年第2期10卷 1-23页

作者： Chenxu zhu Huseyin Ekinci Aixi Pan Bo Cui Xiaoli zhu Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology(WIN) University of WaterlooWaterlooONCanada

E-beam lithography is a powerful tool for generating nanostructures and fabricating nanodevices with fine features approaching a few nanometers in size.However,alternative approaches to conventional spin coating and development processes are required to optimize the lithography procedure on irregular surfaces.In this review,we summarize the state of the art in nanofabrication on irregular substrates using e-beam lithography.To overcome these challenges,unconventional methods have been developed.For instance,polymeric and nonpolymeric materials can be sprayed or evaporated to form uniform layers of electron-sensitive materials on irregular substrates.Moreover,chemical bonds can be applied to help form polymer brushes or self-assembled monolayers on these surfaces.In addition,thermal oxides can serve as resists,as the etching rate in solution changes after e-beam exposure.Furthermore,e-beam lithography tools can be combined with cryostages,evaporation systems,and metal deposition chambers for sample development and lift-off while maintaining low temperatures.Metallic nanopyramids can be fabricated on an AFM tip by utilizing ice as a positive resistor.Additionally,Ti/Au caps can be patterned around a carbon nanotube.Moreover,3D nanostructures can be formed on irregular surfaces by exposing layers of anisole on organic ice surfaces with a focused e-beam.These advances in e-beam lithography on irregular substrates,including uniform film coating,instrumentation improvement,and new pattern transferring method development,substantially extend its capabilities in the fabrication and application of nanoscale structures.

关键词： lithography beam coating

Wood of trees:Cellular structure,molecular formation,and genetic engineering

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Journal of Integrative Plant Biology 2024年第3期66卷 443-467页

作者： Yingying zhu Laigeng Li State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems and College of Ecology Lanzhou UniversityLanzhou 730000China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghai 200032China

Wood is an invaluable asset to human society due to its renewable nature,making it suitable for both sustainable energy production and material manufacturing.Additionally,wood derived from forest trees plays a crucial role in sequestering a significant portion of the carbon dioxide fixed during photosynthesis by terrestrial plants.Nevertheless,with the expansion of the global population and ongoing industrialization,forest coverage has been substantially decreased,resulting in significant challenges for wood production and supply.Wood production practices have changed away from natural forests toward plantation forests.Thus,understanding the underlying genetic mechanisms of wood formation is the foundation for developing high-quality,fast-growing plantation trees.Breeding ideal forest trees for wood production using genetic technologies has attracted the interest of many.Tremendous studies have been carried out in recent years on the molecular,genetic,and cell-biological mechanisms of wood formation,and considerable progress and findings have been achieved.These studies and findings indicate enormous possibilities and prospects for tree improvement.This review will outline and assess the cellular and molecular mechanisms of wood formation,as well as studies on genetically improving forest trees,and address future development prospects.

关键词： cambium cell wall Populus wood formation xylem

Compositional evolution for mixed aerosols containing gluconic acid and typical nitrate and the effect of multiply factors on hygroscopicity

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Journal of Environmental Sciences 2024年第5期139卷 206-216页

作者： Yue zhu Shufeng Pang Yunhong Zhang School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing 100081China

The aging process of atmospheric aerosols usually leads to a mixture of inorganic salts and organic compounds of anthropogenic origin.In organic compounds,polyhydroxy organic acids are important components,however,the study on composition and hygroscopic properties of the mixture containing inorganics and polyhydroxy organic acids is scanty.In this study,gluconic acid,the proxy of polyhydroxy organic acids,is mixed with the representative nitrate(Mg(NO_(3))_(2),Ca(NO_(3))_(2))to form aerosols.ATR-FTIR and optical microscopy are employed to study the component changes and hygroscopicity as a function of relative humidity.As relative humidity fluctuates,the FTIR-ATR spectra display that the internal mixed gluconic acid(CH_(2)(CH)_(4)(OH)_(5)COOH)and nitrate can react to release acidic gases,forming relevant gluconate and further affecting the hygroscopicity.The specific presentation is particles cannot be recovered to their original size after the dehydration-hydration process and there will be some disparities in GF for mixed particles.For the gluconic acid-Ca(NO_(3))_(2)/Mg(NO_(3))_(2)mixtures with molar ratios of 1:1,higher degree of reaction resulting in the production of large amounts of gluconate should be responsible to the lower hygroscopicity compared to ZSR model.For 1:2 gluconic acid-nitrate mixed systems(with higher nitrate content),the hygroscopicity of mixtures are higher than the ZSR prediction.A possible reason could be‘salt-promoting effect’on the organic fractions of the surplus inorganic salt in the mixture.These data can improve the chemical composition list evaluation,in turn hygroscopic properties and phase state of atmospheric aerosol,and then the climate effect.

关键词： Hygroscopicity Gluconic acid Reaction ZSR simulation Size growth factors