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Comparing surface erosion processes in four soils from the loess Plateau under extreme rainfall events

International Soil and Water Conservation Research 2021年第4期9卷 520-531页

作者： liying Sun john l.zhou Qiangguo Cai Suxia liu Jingan Xiao Key laboratory of Water Cycle and Related land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China School of Civil and Environmental Engineering University of Technology Sydney15 BroadwayNSW 2007Australia

This research aims to improve erosion control practice in the loess Plateau,by studying the surface erosion processes,including splash,sheet/interrill and rill erosion in four contrasting soils under high rainfall intensity(120 mm h^(−1))with three-scale indoor artificial *** contrasting soils as sandy loam,sandy clay loam,clay loam and loamy clay were collected from different parts of the loess *** results showed that sediment load was significantly impacted by soil properties in all three *** rate(4.0-21.6 g m^(−2∙)min^(−1))was highest in sandy loam from the north part of the loess Plateau and showed a negative power relation with the mean weight diameter of aggregates after 20 min of rainfall *** average sediment load by sheet/interrill erosion(6.94-42.86 g m^(−2∙)min^(−1))was highest in clay loam from middle part of the loess Plateau,and the stable sediment load after 20 min showed a positive power relation with the silt content in *** average sediment load increased dramatically by rill and interrill erosion(21.03-432.16 g m^(−2∙)min^(−1)),which was highest in loamy clay from south part of the loess *** average sediment load after the occurrence of rill showed a positive power relation with clay content and a negative power relation with soil organic matter *** impacts of slope gradient on the runoff rate and sediment load also changed with soil *** critical factors varied for different processes,which were the aggregate size for splash erosion,the content of silt particles and slope gradient for sheet/interrill erosion,and the content of clay particles,soil organic matter and slope gradient for rill *** on the results of the experiments,specific erosion control practices were proposed by targeting certain erosion processes in areas with different soil texture and different distribution of slope *** findings from this study should support the improvement of erosion

关键词： Soil erosion process Particle size Surface erosion Cropland management loess Plateau

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Phenanthrene sorption to environmental black carbon in sediments from the Song-liao watershed(China)

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Frontiers of Environmental Science & Engineering 2009年第4期3卷 434-442页

作者： Jinghuan ZHANG Mengchang HE Chunye lIN Ke SUN Bin MEN john l.zhou State Key laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China

Black carbon(BC)in ten contaminated sediments from the Song-liao watershed,NE China,was isolated upon treatments using a combustion method at 375℃,and the isolates’sorption isotherms for phenanthrene(Phen)were *** sorption isotherms were nonlinear and fitted well by the Freundlich model.A negative relation was found between Freundlich sorption nonlinearity parameter(n values)and BC/total organic carbon(TOC)content of the original sediments(r^(2)=0.687,plates from this industrialized region had n values of 0.342 to 0.505 and logKFOC values of 6.02 to 6.42(μg·kg^(–1)·OC^(–1))/(μg·l^(–1))n for *** a given Ce,the BC had higher Koc value than the original sediments,revealing a higher sorption capacity for *** was responsible for 50.0%to 87.3%of the total sorption at Ce=0.05 Sw,clearly indicating the dominance of BC particles in overall sorption of Phen by sediments.

关键词： phenanthrene sorption black carbon sediment Song-liao watershed

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Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo Zhang Jie Dang Jia Guo Hanghang zhou Xuewei lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

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A SIMUlATION STUDY OF DEPOSITION UNDER TWO TYPES OF IMPINGING TRAJECTORIES

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Acta Metallurgica Sinica(English letters) 2004年第6期17卷 876-880页

作者： X.Q.Wei l.zhou SchoolofMaterialsScience＆Engineering NanchangUniversityNanchang330047China

A model coupling particle aggregation and randomwalk surface diffusion has been developed for 2D simulation of depositional growth, in which impinging particles follow either a straight-line trajectory of cosine distribution, representing typically sputter deposition, or a scattered trajectory, representing typically electrochemical deposition. Simulations of the growth under various impinging conditions and effective surface diffusivity have been carried out. Pattern and defect development in deposition on flat, trenched and ridged substrates have been investigated. We found that on flat and ridged substrates, both types of trajectories yield similar features, including formation of cone-like defects on surface ridges. While on trenched substrate, the straight-line impingement yielded more uniform step coverage than the scattered impingement.

关键词： deposition simulation pattern formation ballistic model

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NANOSIZE EFFECT IN GRAIN BOUNDARY MIGRATION OF COPPER

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Acta Metallurgica Sinica(English letters) 2004年第1期17卷 11-15页

作者： l.zhou X.Q.Wei N.G.zhou D.G.li School of Materials Science and Engineering Nanchang UniversityNanchang 330047ChinaSchool of Materials Science and EngineeringNanchang UniversityNanchang 330047ChinaSchool of Materials Science and EngineeringNanchang UniversityNanchang 330047ChinaCentral Iron and Steel Research InstituteBeijing 100083China

Molecular dynamics simulations of high temperature annealing of copper bicrystals have been carried out. The bicrystals have planar grain boundaries, and the gain size varies in nano range. An EAM (embedded atom method) potential of FS type is used for calculating the interatomic forces. The results show that in nanocrystalline copper, GB migration driven by inter-GB reaction can take place. A critical grain size is identified, below which the inter-GB reaction becomes strong enough to trigger GB motion, which accelerates rapidly and leads to annihilation of the grain boundaries. The critical size is found to be 16 atomic radii. A "through intermediate grain mechanism" is identified for the nano-grain boundary motion observed, which is never reported for GB migrations of conventional polycrystalline metals.

关键词： grain boundary migration nanocrystal copper

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lessons on mobile apps for COVID-19 from China

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Journal of Safety Science and Resilience 2021年第2期2卷 40-49页

作者： Sophia l.zhou Xianhan Jia Samuel P.Skinner William Yang Isabelle Claude Mass Academy of Math and Science Worcester Polytechnic Institute85 Prescott StreetWorcesterMA 01605United States Department of Computer Science Worcester Polytechnic Institute100 Institute RoadWorcesterMA 01609United States Department of Physics Worcester Polythenic Institute100 Institute RoadWorcesterMA 01609United States Department of Biomedical Engineering Worcester Polytechnic Institute100 Institute RoadWorcesterMA 10609United States

The COVID-19 pandemic has impacted the global society and human life *** countries have launched COVID-19 mobile apps with a wide range in how these apps *** it is hoped that these apps can assist in the fight against COVID-19,many are worried about user *** implemented“health code”systems,which assigned neighborhoods and citizens a specific health code,meant to indicate their risk of having been exposed to *** most widely used health code systems were hosted on the popular apps WeChat and Alipay,each with billions of *** experts argued that China’s use of mobile applications was essential to its successful combat against *** in this study are a summary of mobile technology usage in China,a review of previous studies of mobile technology in healthcare,and a brief survey of some existing mobile applications for COVID-19 that were *** included are outcomes of interviews with healthcare and public safety experts and a public survey to understand how mobile applications were used in China’s response to *** interviews revealed four important themes:personal privacy,community involvement,government involvement,and situational *** was found that a key concern was maintaining a balance between collecting and utilizing personal information,as well as protecting this *** addition,close collaboration between local communities and the national government was *** applications assisted in communication and coordination but did not replace the work of people such as delivery drivers and contact *** results also showed that there was room for improvement,especially accessibility for the elderly or those unfamiliar with *** results were obtained from our *** was interesting to find that the apps were mostly used for“accessing information on COVID-19.”In addition,respondents overwhelmingly identified“information”as the most valuable featur

关键词： Mobile apps COVID-19 response Survey Interview lessons

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A hidden precipitation scenario of theθ’-phase in Al-Cu alloys

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Journal of Materials Science & Technology 2021年第16期75卷 126-138页

作者： l.zhou C.l.Wu P.Xie F.J.Niu W.Q.Ming K.Du J.H.Chen center for high-resolution electron microscopy college of materials science and engineeringhunan universitychangshahunan410082china shenyang national laboratory for materials science institute of metal researchchinese academy of sciences.shenyan7.110016china

Al-Cu binary alloys are important and interesting industry *** to date,the formation mechanisms of the key strengthening precipitates,namedθ’-phase,in the alloys are still ***,we report that for non-deformed bulk Al-Cu alloys theθ’-phase actually has its own direct precursors that can form only at elevated aging temperature(>ca.200℃).These high-temperature precursors have the same plate-like morphology as theθ’-phase precipitates but rather different *** imaging reveals that they have a tetragonal structure with a=0.405 nm and c=1.213 nm,and an average composition of Al_(5-x)Cu_(1+x)(0≤xlly coherent with the *** precursor phase may initiate with a composition of Al5 Cu and evolve locally towards Al_(4)Cu_(2)in composition,eventually leading to a consequent structural transformation into theθ’-phase(Al4 Cu2=Al2 Cu).There are evidences that because of their genetic links in structure,such a high-temperature precursor may transform to theθ’-phase without having to change their morphology and interface *** study reveals a well-defined and previously hidden precipitation scenario for theθ’-phase to form in Al-Cu alloys at an elevated aging temperature.

关键词： AlCu alloy Age-hardening Precipitation Electron microscopy

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Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion

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Neural Regeneration Research 2025年第4期20卷 1192-1206页

作者： Tyler A.Smith liwen zhou Cameron l.Ghergherehchi Michelle Mikesh Cathy Z.Yang Haley O.Tucker JuliAnne Allgood Jared S.Bushman George D.Bittner Department of Molecular Biosciences University of Texas at AustinAustinTXUSA Department of Neuroscience University of Texas at AustinAustinTXUSA Division of Pharmaceutical Sciences University of WyomingLaramieWYUSA

Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal ***,such peripheral nerve allografts undergo immunological rejection by the host immune *** contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian *** relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this *** hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral *** examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal ***-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host *** to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days *** morphological signs of rejection,such as col

关键词： allograft rejection axotomy macrophage myelin nerve repair polyethylene glycol(PEG) sciatic nerve T cell transplantation Wallerian degeneration

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Controlled cationic ring-opening polymerization of l-lactide by organic ion pair: novel approach to isotactic-rich and crystalline polylactide

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Science China Chemistry 2025年第1期 394-402页

作者： Zhiqiang Ding Mingqian Wang Zijing zhou Bin Wang Yuesheng li Tianjin Key laboratory of Composite & Functional Materials School of Materials Science and Engineering Tianjin University

living/controlled cationic ring-opening polymerization （ROP） of l-lactide is a promising approach to isotactic-rich and crystalline poly（l-lactide）.In contrast with the unsubstituted lactones,l-lA can not be polymerized by organic lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of l-lA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of l-lA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid l-lA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PllA without transesterification and epimerization side *** activated chain end mechanism,involving twice SN2 substitution and configuration-inversion （S→R→S） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of l-lA catalyzed by an organic ion pair.

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Spatial transcriptomics combined with single-nucleus RNA sequencing reveals glial cell heterogeneity in the human spinal cord

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Neural Regeneration Research 2025年第11期20卷 3302-3316页

作者： Yali Chen Yiyong Wei Jin liu Tao Zhu Cheng zhou Donghang Zhang Department of Anesthesiology West China HospitalSichuan UniversityChengduSichuan ProvinceChina laboratory of Anesthesia and Critical Care Medicine National-Local Joint Engineering Research Center of Translational Medicine of AnesthesiologyWest China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of Anesthesiology Longgang District Maternity&Child Healthcare Hospital of Shenzhen City(Longgang Maternity and Child Institute of Shantou University Medical College)ShenzhenGuangdong ProvinceChina Department of Anesthesiology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Glial cells play crucial roles in regulating physiological and pathological functions,including sensation,the response to infection and acute injury,and chronic neurodegenerative *** cells include astrocytes,microglia,and oligodendrocytes in the central nervous system,and satellite glial cells and Schwann cells in the peripheral nervous *** the greater understanding of glial cell types and functional heterogeneity achieved through single-cell and single-nucleus RNA sequencing in animal models,few studies have investigated the transcriptomic profiles of glial cells in the human spinal ***,we used high-throughput single-nucleus RNA sequencing and spatial transcriptomics to map the cellular and molecular heterogeneity of astrocytes,microglia,and oligodendrocytes in the human spinal *** explore the conservation and divergence across species,we compared these findings with those from *** the human spinal cord,astrocytes,microglia,and oligodendrocytes were each divided into six distinct transcriptomic *** the mouse spinal cord,astrocytes,microglia,and oligodendrocytes were divided into five,four,and five distinct transcriptomic subclusters,*** comparative results revealed substantial heterogeneity in all glial cell types between humans and ***,we detected sex differences in gene expression in human spinal cord glial ***,in all astrocyte subtypes,the levels of NEAT1 and CHI3l1 were higher in males than in females,whereas the levels of CST3 were lower in males than in *** all microglial subtypes,all differentially expressed genes were located on the sex *** addition to sex-specific gene differences,the levels of MT-ND4,MT2A,MT-ATP6,MT-CO3,MT-ND2,MT-ND3,and MT-CO_(2) in all spinal cord oligodendrocyte subtypes were higher in females than in ***,the present dataset extensively characterizes glial cell heterogeneity and offers a valuable resource for explo

关键词： astrocyte glial cell human microglia oligodendrocyte sex differentiation single-nucleus RNA sequencing spatial transcriptomics species variation spinal cord

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