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Study on the Synthesis and Adsorption Properties of KH-560 modified PalygorskiteSupported β-Cyclodextrin

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复旦学报（自然科学版） 2007年第5期46卷 788-,791页

作者： d.m.zhu L.YAN X.L.SHI Y.CHANG Key Laboratory of Polymer materials of Gansu Province College of Chemistry and Chemical EngineeringNorthwest Normal University

1 Results Palygorskite (PGS) is a chain-layer magnesium-aluminum silicate mineral. Because of its developed interior channels and large specific surface area, and thus considerable adsorption capacity, it has been studied for the application as one of environmental mineral adsorbents[1-3]. Cyclodextrins (Cd) possess a hydrophilic exterior and a hydrophobic interior into which a variety of hydrophobic organic molecules maybe introduced. The Cd molecule not only affects a hydrophilic cavity on the nanomet...

关键词： KH-560 modified palygorskite β-cyclodextrin adsorption phenolic compounds

THE EFFECT OF mELTING TEmPERATURE ON THE PROPERTIES OF PbBr _2-PbCl_2-P_2O_5 GLASSES

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Acta metallurgica Sinica(English Letters) 1999年第5期12卷 1153-1158页

作者： H.S.Zhao,W.C.Zhou, d.L.Zhao and d.m.zhu State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072,China

A series of PbBr 2 PbCl 2 P 2O 5 glasses have been prepared and characterized to research the effect of melting temperature on the properties of glasses. The glass forming regions have been explored and the stability of the glasses against crystallization studied. The density, characteristic temperatures, chemical analysis compositions, and infrared absorption spectra of the glasses were measured. Results show that the PbBr 2 PbCl 2 P 2O 5 ternary system melted at 530～540℃ has a broader glass forming region which extended to the side of PbBr2 than that melted at 450～470℃. The glass transition temperature is more than 200℃ and the density is more than 5 5 g·cm 3 . Both the chemical analysis composition and the infrared absorption spectra of some glasses melted at 530～540℃ show that the decomposition of NH 4H 2PO 4 is more complete than that of glasses melted at 450～470℃.

关键词： phosphate glasses melting temperature property

Stress-strain relationship for reactive powder concrete with recycled powder under uniaxial compression

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1015-1027页

作者： Peng zhu Yunming zhu Wenjun QU Liyu XIE College of Civil Engineering Tongji UniversityShanghai 200092China Key Laboratory of Performance Evolution and Control for Engineering Structures of ministry of Education Tongji UniversityShanghai 200092China

The recycled powder(RP)from construction wastes can be used to partially replace cement in the preparation of reactive powder *** this paper,reactive powder concrete mixtures with RP partially replacing cement,and natural sand instead of quartz,are *** curing is used,instead of steam curing that is normally requested by standard for reactive powder *** influences of RP replacement ratio(0%,10%,20%,30%),silica fume proportion(10%,15%,20%),and steel fiber proportion(0%,1%,2%)are *** effects of RP,silica fume,and steel fiber proportion on compressive strength,elastic modulus,and relative absorption energy are analyzed,and theoretical models for compressive strength,elastic modulus,and relative absorption energy are established.A constitutive model for the uniaxial compressive stress-strain relationship of reactive powder concrete with RP is *** the increase of RP replacement ratio from 0% to 30%,the compressive strength decreases by 42% and elastic modulus decreases by 24%.

关键词： recycled powder reactive powder concrete elastic modulus relative absorbed energy stress-strain relationship

Old Pinus massoniana forests benefit more from recent rapid warming in humid subtropical areas of central-southern China

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Journal of Forestry Research 2024年第5期35卷 155-170页

作者： Wenxin Li Liangjun zhu Lianhua zhu mengdan Jing Censhi Qian Yu zhu Paolo Cherubini College of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004People’s Republic of China Swiss Federal Institute for Forest Snow and Landscape Research WSL8903 BirmensdorfSwitzerland department of Forest and Conservation Sciences Faculty of ForestryUniversity of British Columbia2004-2424 Main MallVancouverBC V6T 1Z4Canada

Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environmental *** the importance of age-related growth responses on overall forest health and management policies,limited knowledge exists regarding age-related effects on dendroclimatic relationships in key subtropical tree *** this study,we employed a den-drochronological method to examine the impact of rapid warming on growth dynamics and climatic sensitivity of young(40–60 years)and old(100–180 years)Pinus mas-soniana forests across six sites in central-southern *** normalized log basal area increment of trees in both age groups increased significantly following rapid warming in *** in young forests further showed a distinct growth decline during a prolonged severe drought(2004–2013),whereas those in old forests maintained growth *** growth was more strongly influenced by temperature than by moisture,particularly in old *** tem-peratures strongly and positively impacted the growth of old trees but had a weaker effect on young *** forests had a significantly lower resistance to extreme drought but faster recovery compared to young ***“divergence problem”was more pronounced in younger forests due to their heightened sensitivity to warming-induced drought and heat *** ongoing warming,young forests also may initially experience a growth decline due to their heightened sensitivity to winter *** findings underscore the importance of considering age-dependent changes in forest/tree growth response to warming in subtropical forest man-agement,particularly in the context of achieving“Carbon Peak&Carbon Neutrality”goals in China.

关键词： Tree rings Pinus massoniana Age effects drought resilience Subtropical forests Rapid warming

Efficient Removal of Phosphate from Aqueous Solutions Using Corundum-hollow-spheres Supported Caclined Hydrotalcite Porous Thin Films

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Journal of Wuhan University of Technology(materials Science) 2024年第1期39卷 44-49页

作者：刘云才 zhu Chen School of Architecture and materials Engineering Hubei Second Normal UniversityWuhan 430205China

Phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 min and cHT thin films were obtained by annealing of the HT thin films at 500℃for 180 min. Their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRd) and scanning electron microscopy (SEm).The results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. The mechanism of nucleation and growth of the HT thin films was fitted well with the anion coordination polyhedron growth unit model. To determine the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/min) were examined by column experiments. The highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). The adsorption capacity increased as the bed depth increased and decreased as the flow rate increased.

关键词： adsorption phosphate hydrotalcite corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal

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 ***,alternative approaches to conventional spin coating and development processes are required to optimize the lithography procedure on irregular *** this review,we summarize the state of the art in nanofabrication on irregular substrates using e-beam *** overcome these challenges,unconventional methods have been *** instance,polymeric and nonpolymeric materials can be sprayed or evaporated to form uniform layers of electron-sensitive materials on irregular ***,chemical bonds can be applied to help form polymer brushes or self-assembled monolayers on these *** addition,thermal oxides can serve as resists,as the etching rate in solution changes after e-beam ***,e-beam lithography tools can be combined with cryostages,evaporation systems,and metal deposition chambers for sample development and lift-off while maintaining low *** nanopyramids can be fabricated on an AFm tip by utilizing ice as a positive ***,Ti/Au caps can be patterned around a carbon ***,3d nanostructures can be formed on irregular surfaces by exposing layers of anisole on organic ice surfaces with a focused *** 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

Predicting effects of tunnel throttling of annular freeway vehicular flow by a continuum model

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 733-746页

作者： Zhongmin Huang m.N.Smirnova N.N.Smirnov Zuojin zhu Faculty of Engineering Science University of Science and Technology of ChinaHefei 230026China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Faculty of mechanics and mathematics Lomonosov Moscow State UniversityMoscow 119992Russia

Fluid flow throttling is common in industrial and building services *** tunnel throttling of vehicular flow is caused by the abrupt number reduction of roadway lane,as the tunnel has a lower lane number than in the roadway normal *** predict the effects of tunnel throttling of annular freeway vehicular flow,a three-lane continuum model is ***Ⅲof the tunnel is completely blocked due to the need of tunnel rehabilitation,*** exists mandatory net lane-changing rate from laneⅢto laneⅡjust upstream of the tunnel entrance,which is described by a model of random number generated through a golden section *** net-changing rate between adjacent lanes is modeled using a lane-changing time expressed explicitly in algebraic *** paper assumes that the annular freeway has a total length of 100 km,a two-lane tunnel of length 2 km with a speed limit of 80 km/*** free flow speeds on lanesⅠ,ⅡandⅢare assumed to be 110,100 and 90 km/h *** on the three-lane continuum model,numerical simulations of vehicular flows on the annular freeway with such a tunnel are conducted with a reliable numerical method of 3rd-order *** results reveal that the vehicular flow has a smaller threshold of traffic jam formation in comparison with the case without tunnel *** fuel consumption can be estimated by interpolation with time averaged grid traffic speed and an assumed curve of vehicle *** vehicle fuel consumption is lane number dependent,distributes with initial density concavely,ranging from 5.56 to 8.00 *** throttling leads to an earlier traffic jam formation in comparison with the case without tunnel throttling.

关键词： Effects of tunnel throttling Vehicle fuel consumption Travel time Threshold of traffic jam formation Continuum model

modulating the degree of O vacancy defects to achieve selective control of electrochemical CO_(2) reduction products

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Chinese Chemical Letters 2024年第5期35卷 482-486页

作者： Tianbo Jia Lili Wang Zhouhao zhu Baikang zhu Yingtang Zhou Guoxing zhu mingshan zhu Hengcong Tao School of Petrochemical Engineering&Environment Zhejiang Ocean UniversityZhoushan 316022China department of General Practice First Medical CenterChinese PLA General HospitalBeijing 100853China National&Local Joint Engineering Research Center of Harbor Oil&Gas Storage and Transportation Technology Zhoushan 316022China School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013China Guangdong Key Laboratory of Environmental Pollution and Health School of EnvironmentJinan UniversityGuangzhou 511443China

Conversion of CO_(2) into high-value products using electrochemical CO_(2) reduction(ECR)technology is an effective way to alleviate global warming and reach carbon *** oxygen vacancies in heterogenous catalysis are generally considered as a powerful method to enhance the performance of ECR by promoting CO_(2) adsorption and ***,the extent of defects in oxygen vacancies-activity relation has rarely been ***,we prepared Cu-Cd bimetallic catalysts with adjustable oxygen defect degree by controlling the amount of cadmium *** transform infrared spectroscopy characterization results reveal that the formation of oxygen vacancies is attributed to the asymmetric stretching of Cu-O by the addition of *** results show that the oxygen defect degree can modulate the selectivity of ECR products.A low degree of oxygen defects(CuO)is generally associated with lower product Faraday efficiency(FE_(C2)/FE_(C1)≈114%),but overabundant oxygen vacancies(CuO_(2.625)-CdO_(0.375))are not entirely favorable to improving ECR activity(FE_(C2)/FE_(C1)≈125%)and single selectivity,while an appropriate degree of oxygen vacancies(CuO_(2.75)-CdO_(0.25))can facilitate the ECR process toward single product selective production(FE_(C2)/FE_(C1)≈296%).The theoretical calculation showed that the O vacancy formed on CuO and the interface between CdO and CuO were conducive to enhancing the formation of ^(*)COOH intermediate and promoting the generation of ethylene *** study provides a new approach and insight into the selective production of single products for future industrial applications of ECR.

关键词： CO_(2) O-vacancies Bimetallic catalysts Copper oxide Cadmium oxide Selective

Theoretical modeling and Surface Roughness Prediction of microtextured Surfaces in Ultrasonic Vibration-Assisted milling

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Chinese Journal of mechanical Engineering 2024年第2期37卷 163-183页

作者： Chenbing Ni Junjie zhu Youqiang Wang dejian Liu Xuezhao Wang Lida zhu School of mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266525China School of mechanical Engineering and Automation Northeastern UniversityShenyang 110819China

Textured surfaces with certain micro/nano structures have been proven to possess some advanced functions,such as reducing friction,improving wear and increasing *** prediction of micro/nano surface textures is of great significance for the design,fabrication and application of functional textured *** this paper,based on the kinematic analysis of cutter teeth,the discretization of ultrasonic machining process,transformation method of coordinate systems and the cubic spline data interpolation,an integrated theoretical model was established to characterize the distribution and geometric features of micro textures on the surfaces machined by different types of ultrasonic vibration-assisted milling(UVAm).Based on the theoretical model,the effect of key process parameters(vibration directions,vibration dimensions,cutting parameters and vibration parameters)on tool trajectories and microtextured surface morphology in UVAm is ***,the effect of phase difference on the elliptical shape in 2d/3d ultrasonic elliptical vibration-assisted milling(UEVAm)was *** to conventional numerical models,the method of the cubic spline data interpolation is applied to the simulation of microtextured surface morphology in UVAm,which is more suitable for characterizing the morphological features of microtextured surfaces than traditional methods due to the presence of numerous micro *** prediction of surface roughness indicates that the magnitude of ultrasonic amplitude in z-direction should be strictly limited in 1d rotary UVAm,2d and 3d UEVAm due to the unfavorable effect of axial ultrasonic vibration on the surface *** study can provide theoretical guidance for the design and fabrication of microtextured surfaces in UVAm.

关键词： Theoretical modeling microtextured surface Ultrasonic vibration-assisted milling Cubic spline interpolation Surface roughness