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Thermal-water-salt coupling process of unsaturated saline soil under unidirectional freezing

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Journal of Mountain Science 2023年第2期20卷 557-569页

作者： luo chong-liang YU Yun-yan ZHANG Jing TAO Jing-yan OU Qing-jie CUI Wen-hao School of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730070China School of Civil Engineering Hexi UniversityZhangye 734000China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Salinization and desertification are closely related to water-salt migration caused by a temperature *** on the Darcy Law of unsaturated soils,the law of energy conservation and the law of mass conservation,the thermal-water-salt coupling mathematical model of unsaturated frozen saline soil was *** model considered the latent heat of phase change,crystallization impedance,crystallization consumption and complete precipitation of solute crystallization in *** order to verify the rationality of the model,the unidirectional freezing test of unsaturated saline soil was carried out in an open system with no-pressure water supplement to obtain the spatial distribution of temperature,moisture and salt in the saline ***,numerical simulations are implemented with the assistance of COMSOL *** of the model is illustrated by comparisons between the simulation and experimental *** results demonstrated that the temperature within saline soil changes with time and can be divided into three stages,namely quick freezing stage,transitional stage and stable *** water and salt contents in the freezing zone are layered,with peak values at the freezing *** coupled model could reveal the heat-mass migration mechanism of unsaturated frozen saline soil and dynamically describe the freezing depth and the movement law of the freezing front,ice and salt crystal formation mechanism,and the change law of thermal conductivity and permeability coefficient.

关键词： Unsaturated sulfate saline soil Watersalt migration Crystallization latent heat Crystallization impedance Mathematical model

不同饲喂方式对早期断奶“茶卡羊”羔羊生长性能、养殖收益及血清生化指标的影响

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西南农业学报 2024年第3期37卷 648-655页

作者：刘宏金许显莉韩学平张骞郭同庆王循刚罗崇亮胡林勇赵娜才让周在徐世晓中国科学院西北高原生物研究所/中国科学院三江源国家公园研究院西宁810008 中国科学院高原生物适应和进化重点实验室西宁810008 中国科学院大学北京100049 青海省畜牧总站西宁810001 青海省刚察县畜牧兽医工作站青海刚察810399

【目的】探究早期断奶后不同饲喂方式对舍饲羔羊生长性能、养殖收益及血清生化指标的影响。【方法】选取体重(5.94±0.34)kg、日龄(20±1)相近的健康茶卡羊公羔40只,用耳标标记,随机分为早期断奶组(A、B、C组)和随母哺乳组(D组,对照),每... 详细信息

【目的】探究早期断奶后不同饲喂方式对舍饲羔羊生长性能、养殖收益及血清生化指标的影响。【方法】选取体重(5.94±0.34)kg、日龄(20±1)相近的健康茶卡羊公羔40只,用耳标标记,随机分为早期断奶组(A、B、C组)和随母哺乳组(D组,对照),每组10只。早期断奶组羔羊于21日龄开始断奶并用代乳粉替代饲喂至60日龄后进行不同日粮组合饲喂,即A组:开食料+燕麦青干草+玉米青贮;B组:开食料+燕麦青干草;C组:开食料+玉米青贮,饲喂时间为65 d。D组羔羊随母哺乳至试验结束。【结果】生长性能方面,A组羔羊增质量(16.43 kg)、平均日增重(156.48 g/d)、增重比例(362.32%)及饲料转化效率(4.28)显著高于其它各处理组(P0.05,下同)。养殖收益方面,随母哺乳组羔羊收益最低(171.16元/只),断奶后A组饲喂方式显著提高羔羊养殖收益,为217.35元/只。不同饲喂方式显著影响羔羊血清部分激素、氮代谢及免疫功能;激素方面,生长激素(GH)、胰岛素生长因子(IGF-1)和胃泌素含量A组显著高于其它各处理组;氮代谢方面,A组显著提升羔羊氮代谢能力,主要表现为较低的尿素氮(7.12 mmol/L)和尿酸含量(122.25μmol/L);免疫功能方面,免疫球蛋白G(IgG)和免疫球蛋白A(IgA)含量在A组显著高于其它处理组。免疫球蛋白M(IgM)在各处理组间无显著差异。【结论】茶卡羊羔羊早期断奶后采用开食料、玉米青贮和燕麦青干草混合饲喂方式有利于其生长性能、养殖收益及机体各功能的发挥。农牧民应树立羔羊早期断奶观念,在早期断奶后通过科学的饲喂管理提升羔羊养殖水平,以期获得良好的生长性能及养殖收益。

关键词：早期断奶羔羊饲喂方式生长性能养殖收益血清生化指标

Comprehensive tensile properties improved by deep cryogenic treatment prior to aging in friction-stir-welded 2198 Al–Li alloy

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Rare Metals 2024年第10期43卷 5403-5409页

作者： Jian-Qiu Sun Yue Ma chong Gao Hong-Yun luo School of Materials Science and Engineering Beihang University Chinalco Research Institute of Science and Technology

In order to improve the comprehensive mechanical properties,deep cryogenic treatment （DCT）prior to aging was carried out on friction-stir-welded（FSW） 2198 Al-Li alloy;afterward,the microstructure and tensile properties were characterized by means of optical microscopy （OM）,transmission electron microscopy（TEM） and tensile *** results show that FSW 2198 alloy through DCT prior to aging （DAT） possesses superior tensile properties than conventional aging treatment （AT）The microstructural analysis reveals that DAT alloy exhibits a finer grain structure,since DCT might effectively alleviate the residual stress in FSW 2198 alloy and thus decrease the driving force for grain coarsening in subsequent aging ***,DCT generates dislocation multiplication,which provides more preferential nucleation sites for T1 （Al2CuLi） phase during subsequent aging treatment,resulting in high-density fine T1 phases and thin precipitate-free zone within DAT *** reasonable microstructure leads to DAT alloy possessing better strength-ductility combination compared to AT alloy.

关键词： Al–Li alloy Deep cryogenic treatment Friction stir welding Tensile properties

Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution

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Petroleum Science 2024年第3期21卷 1765-1779页

作者： Yan-Zhong liang Bai-Lu Teng Wan-Jing luo School of Energy Resources China University of Geosciences(Beijing)Beijing100083China

During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional ***,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field ***,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux ***,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow *** using the finite difference method,we can obtain the numerical solutions of the transient flow within the *** the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the *** complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient ***,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional *** computation results show that the flux variation along the direction well has a significant effect on pressure *** addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial *** horizontal linear flow can be observed only if the formation thickness is much smaller than the well ***,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore.

关键词： Directional well Pressure transient behavior Semi-analytical model Non-uniform flux

High-Order Two-Scale Asymptotic Paradigm for the Elastodynamic Homogenization of Periodic Composites

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Acta Mechanica Solida Sinica 2024年第1期37卷 124-138页

作者： Wei-Zhi luo Mu He liang Xia Qi-Chang He State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Laboratoire Modélisation et Simulation Multi-Echelle MSME UMR 8208 CNRSUniversite Gustave Eiffel77454 Marne-la-ValléeFrance

The classical two-scale asymptotic paradigm provides macroscopic and microscopic analyses for the elastodynamic homogenization of periodic composites based on the spatial or/and temporal variable,which offers an approximate framework for the asymptotic homogenization analysis of the motion ***,in this framework,the growing complexity of the homogenization formulation gradually becomes an obstacle as the asymptotic order *** such a context,a compact,fast,and accurate asymptotic paradigm is *** work reviews the high-order spatial two-scale asymptotic paradigm with the effective displacement field representation and optimizes the implementation by symmetrizing the tensor to be ***,the modified implementation gets rid of the excessive memory consumption required for computing the high-order tensor,which is demonstrated by representative one-and two-dimensional *** numerical results show that(1)the contrast of the material parameters between media in composites directly affects the convergence rate of the asymptotic results for the homogenization of periodic composites,(2)the convergence error of the asymptotic results mainly comes from the truncation error of the modified asymptotic homogenized motion equation,and(3)the excessive norm of the normalized wavenumber vector in the two-dimensional inclusion case may lead to a non-convergence of the asymptotic results.

关键词： Composites Homogenization Asymptotic analysis Dynamics Dispersion

Sponge as Scaffolds in Bone and Cartilage Tissue Engineering

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Chemical Research in Chinese Universities 2024年第5期40卷 786-797页

作者： luo Lei GONG Yining YAN liang BU Yazhong Yan’an University Yan’an716000P.R.China Department of Spine Surgery Honghui HospitalXi’an Jiaotong UniversityXi’an710054P.R.China Institute of Medical Engineering Department of BiophysicsSchool of Basic Medical SciencesHealth Science CenterXi’an Jiaotong UniversityXi’an710061P.R.China

In recent years,tissue scaffolds have emerged as a new therapeutic method for bone and cartilage regeneration,with sponge scaffolds gaining increasing *** scaffolds possess several favorable characteristics,including appropriate biodegradability,excellent biocompatibility,good processability,powerful osteogenic ability,a unique porous structure,and adjustable pore size and *** attributes make sponge scaffolds a promising option for bone and cartilage ***,to date,there is a lack of comprehensive reviews summarizing the use of sponge scaffolds in this *** this review,our objective is to provide a comprehensive overview of the research progress and development trends of sponge ***,we introduce the various materials used for sponge ***,we summarize the different preparation methods employed for creating sponge ***,we discuss the functional additives that can be incorporated into the ***,we present some special structures that can be achieved in sponge *** aim is for this review to offer valuable insights and serve as a comprehensive resource for the design of sponge scaffolds in cartilage and bone regeneration.

关键词： Bone Sponge Scaffold Tissue regeneration

Epiphytic zooplankton community profiles in a typical urban wetland as revealed by DNA metabarcoding

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Journal of Oceanology and Limnology 2024年第5期42卷 1571-1585页

作者： Diwen liang Chunrong HUANG Senjie LIN Jiahua DONG Mingyi liang Hailin luo State Environmental Protection Key Laboratory of Urban Ecological Simulation and Protection South China Institute of Environmental SciencesMinistry of Ecology and Environment of the People’s Republic of ChinaGuangzhou 510530China Department of Marine Sciences University of ConnecticutGrotonConnecticut 06340USA

Zooplankton,a crucial component of urban wetland,are one of the effective bioindicators for monitoring the feeding stocks of organisms at higher trophic levels and assessing the ecological quality of ***,information about the characteristics of epiphytic zooplankton community structure resulted from traditional methods is limited and hindered by the large amount of detritus and sludge attached to the *** investigated the epiphytic zooplankton communities associated with macrophytes(Vallisneria,Nymphaea,and Thalia dealbata)in a subtropical wetland using as DNA markers of the 18 S rRNA gene and the mitochondrial cytochrome c oxidase subunit I(COI)gene.A total of 241 OTUs of zooplankton were obtained from COI amplicons,including 194 OTUs of Rotifera,22 of Cladocera,and 25 of Copepoda,while only 62 OTUs of zooplankton were obtained from 18 S rDNA amplicons including 34 OTUs of Rotifera and 28 of *** zooplankton communities associated with the three macrophytes were similar,but they differed significantly from those in the open ***,there were no significant temporal differences among the zooplankton *** zooplankton communities were dominated by littoral zooplankton such as Testudinella,Lecane,and ***,especially littoral species,utilize macrophytes as food sources and as refuges against *** further led to an increase inαandβdiversity of zooplankton communities in urban *** result suggests that the joint use of multiple molecular markers could improve the taxonomic resolution and generate a comprehensive biodiversity profile of zooplankton.

关键词： environmental DNA metabarcoding diversity macrophyte cytochrome c oxidase subunit I(COI) 18 S rRNA

Water disinfection:Advances in photocatalysis and piezo/triboelectric catalysis with progressively enhanced energy utilization

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SusMat 2024年第5期4卷 114-138页

作者： Zhidi Chen Mengyao Pan chong Cheng Jing luo Xu Deng Institute of Fundamental and Frontier Sciences School of MedicineSichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengduChina College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengduChina Shenzhen Institute for Advanced Study University of Electronic Science and Technology of ChinaShenzhenChina

Increasing climate-related extreme weather events and conflicts hinder safe water sanitation for vulnerable *** developing areas,centralized water systems are impractical due to high costs and poor ***,technologies utilizing renewable energy like solar and mechanical energy for water treatment hold *** is critical to develop photocatalysts and piezo-electric/triboelectric catalysts that capture solar energy as well as mechanical energy to generate disinfectants to maximize energy *** latest advancements in principles,materials,and processes utilizing solar and mechan-ical energy for water disinfection are highlighted in this ***,we elucidate both direct and indirect mechanisms of sunlight-mediated water dis-infection,discuss the evolution of photocatalysts from simple UV absorption to visible-light utilization,and even near-infrared light exploitation to enhance solar spectrum utilization ***,we delve into the fundamen-tal principles of piezoelectricity and triboelectricity relying on mechanical energy conversion as well as summarize the development of piezo/triboelectric cat-alysts from being driven by high-frequency energy to utilizing low-frequency mechanical energy from the ***,challenges and directions for efficient systems are outlined to inspire rational design strategies and accel-erate the production of superior catalytic systems applicable across a broad range.

关键词： photocatalysis piezo/triboelectric catalysis water disinfection

The journey towards physiology and pathology: Tracing the path of neuregulin 4

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Genes & Diseases 2024年第2期11卷 687-700页

作者： Min Chen Jieying Zhu Hongyang luo Wangjing Mu liang Guo School of Exercise and Health and Shanghai Frontiers Science Research Base of Exercise and Metabolic Health Shanghai University of SportShanghai 200438China

Neuregulin 4 (Nrg4),an epidermal growth factor (EGF) family member,can bind to and activate the ErbB4 receptor tyrosine ***4 has five different isoforms by alternative splicing and performs a wide variety of ***4 is involved in a spectrum of physiological processes including neurobiogenesis,lipid metabolism,glucose metabolism,thermogenesis,and *** pathological processes,Nrg4 inhibits inflammatory factor levels and suppresses apoptosis in inflammatory *** addition,Nrg4 could ameliorate obesity,insulin resistance,and cardiovascular ***,Nrg4 improves non-alcoholic fatty liver disease (NAFLD) by promoting autophagy,improving lipid metabolism,and inhibiting cell death of ***,Nrg4 is closely related to the development of cancer,hyperthyroidism,and some other ***,elucidation of the functional role and mechanisms of Nrg4 will provide a clearer view of the therapeutic potential and possible risks of Nrg4.

关键词： Angiogenesis Cardiovascular diseases Inflammation Insulin resistance Lipid and glucose metabolism NAFLD Neurobiogenesis Obesity