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Chiral Coordination Metallacycles/Metallacages for Enantioselec-tive Recognition and Separation

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Chinese journal of Chemistry 2021年第8期39卷 2273-2286页

作者： Liyan Zhang Huiping liu Guozan Yuan Ying-Feng Han School of Chemistry and Chemical Engineering Institute of Materials Science and EngineeringAnhui University of TechnologyMaanshanAnhui 243032China Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi'anShaanxi 710127China

In recent years,chiral discrete supramolecular coordination complexes have attracted increasing interest as simple enzyme mimetics owing to their aesthetic architectures and potential applications in chiral *** review summarizes the recent advances on chiral coordination metallacy-cles/metallacages with inherent cavities for enanti on selective recog nition and separation,including their design principles and synthesis,the in troduc-tion of chirality and functionality,structural adaptability,and host-guest bonding in enantioselective ***,the perspectives on the remain-ing challenges and future opportunities are presented.

关键词： Chirality Metallacycles Metallacages Molecular recognition Chiral resolution

基于超声波无损检测技术的侧压竹集成材力学性能试验研究

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西北林学院学报 2024年第1期39卷 200-207页

作者：刘丰禄赵扬吴传宇戴俊龙张鸿江杨锦添福建农林大学机电工程学院福建福州350108

探究超声波传播速度与侧压竹集成材力学性能(抗弯弹性模量和抗弯强度)之间的关系模型,结合密度计算出的动态弹性模量和抗弯弹性模量之间的关系模型,为超声波无损检测侧压竹集成材的力学性能提供理论依据。以侧压竹集成材为研究对象,利... 详细信息

探究超声波传播速度与侧压竹集成材力学性能(抗弯弹性模量和抗弯强度)之间的关系模型,结合密度计算出的动态弹性模量和抗弯弹性模量之间的关系模型,为超声波无损检测侧压竹集成材的力学性能提供理论依据。以侧压竹集成材为研究对象,利用超声波微秒计测量仪,通过超声波传播测量试验,得到了超声波在侧压竹集成材和竹板小试样中传播速度,并绘制出侧压竹集成材超声波传播速度的等值线分布图。利用密度计测量竹板小试样的密度和超声波波速计算竹板小试样的动态弹性模量。通过三点弯曲试验得到侧压竹集成材小试样的抗弯弹性模量和抗弯强度,回归分析超声波传播速度与抗弯弹性模量和抗弯强度,以及动态弹性模量与抗弯弹性模量之间的关系。结果表明,虽然采用相同的热压工艺参数,但各个侧压竹集成材所得到的超声波波速等值线分布图存在明显差异,说明各个侧压竹集成材的胶合效果存在差别,导致其之间的力学性能也存在一定的差别,超声波传播速度越大,表明侧压竹集成材的胶合效果或者力学性能越好;超声波波速与侧压竹集成材小试样的抗弯弹性模量和抗弯强度之间存在较好的相关性(决定系数R2分别为0.65和0.59),这说明可以通过超声波波速来合理地预测和评价侧压竹集成材小试样的抗弯弹性模量和抗弯强度;侧压竹集成材小试样的动态弹性模量与其抗弯弹性模量之间也存在良好的相关性,两者的决定系数R2为0.68,这说明也可以通过测量侧压竹集成材小试样的动态弹性模量,来对其抗弯弹性模量进行合理的预测和评价。研究表明,超声波无损检测技术是合理预测和评价侧压竹集成材力学性能的一种潜在的有效手段。

关键词：超声波无损检测竹集成材超声波速力学性能

Fine root litter quality regulates soil carbon storage efficiency in subtropical forest soils

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Soil Ecology Letters 2023年第4期5卷 65-80页

作者： Shan Xu Fanglong Su Emma j.Sayer Shu Kee Lam Xiankai Lu Chengshuai liu Derrick Y.F.Lai Department of Geography and Resource Management The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina South China Botanical Garden Chinese Academy of SciencesGuangzhou 510070China Lancaster Environment Centre Lancaster UniversityLancasterLA14YQUnited Kingdom Smithsonian Tropical Research Institute P.O.Box 0843-03092BalboaAnconPanamaRepublic of Panama School of Agriculture and Food The University of MelbourneVictoria 3010Australia Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management Guangdong Institute of Eco-environmental Science&TechnologyGuangzhou 510650China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Centre for Environmental Policy and Resource Management The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina

●High-quality and low-quality root litter had contrasting patterns of mass loss.●Greater litter-derived C was incorporated into soils under high-quality root litter.●Root litter decay rate or litter-derived C were related to soil microbial diversity.●Root litter quality had little effect on soil physicochemical properties.●High root litter quality was the main driver of enhanced soil C storage *** root litter is a major contributor to soil carbon(C)storage in forest *** decomposition,the quality of root litter could play a critical role in soil C ***,it is unclear whether root litter quality influences soil C storage *** conducted a two-year greenhouse decomposition experiment using 13C-labeled fine root litter of two tree species to investigate how root litter quality,represented by C to nitrogen(C/N)ratios,regulates decomposition and C storage efficiency in subtropical forest soils in China.‘High-quality’root litter(C/N ratio=26)decayed faster during the first year(0−410 days),whereas‘low-quality’root litter(C/N ratio=46)decomposed faster toward the end of the two-year period(598−767 days).However,over the two years of the study,mass loss from high-quality root litter(29.14±1.42%)was lower than‘low-quality’root litter(33.01±0.54%).Nonetheless,root litter C storage efficiency(i.e.,the ratio of new root litter-derived soil C to total mineralized root litter C)was significantly greater for high-quality root litter,with twice as much litter-derived C stored in soils compared to low-quality root litter at the end of the *** litter quality likely influenced soil C storage via changes in microbial diversity,as the decomposition of high-quality litter declined with increasing bacterial diversity,whereas the amount of litter-derived soil C from low-quality litter increased with fungal *** results thus reveal that root litter quality mediates decomposition and C storage in subtropical forest soils in Ch

关键词： fine root litter quality root litter decomposition litter carbon storage efficiency soil organic carbon accumulation subtropical forest

2型糖尿病患者血清铁蛋白水平与血尿酸的关系

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海军军医大学学报 2024年第3期45卷 284-289页

作者：王亚雯李凯蔡静郭梅琦潘斌晶闫均新刘靖芳兰州大学第一临床医学院内分泌科兰州730000 兰州大学第一医院内分泌科兰州730000

目的探究2型糖尿病(T2DM)患者血清铁蛋白(SF)水平与血尿酸(SUA)的关系,为临床上T2DM合并高尿酸血症(HUA)患者的诊治提供新的分子标志物。方法选取2021年8月至2022年9月于兰州大学第一医院内分泌科住院治疗的T2DM患者351例,根据SF的四分... 详细信息

目的探究2型糖尿病(T2DM)患者血清铁蛋白(SF)水平与血尿酸(SUA)的关系,为临床上T2DM合并高尿酸血症(HUA)患者的诊治提供新的分子标志物。方法选取2021年8月至2022年9月于兰州大学第一医院内分泌科住院治疗的T2DM患者351例,根据SF的四分位数水平将其分为4组:q1组(SFq2组(SF为76.2~138.9 ng/mL,88例)、q3组(SF为139.0~240.9 ng/mL,87例)、q4组(SF≥241.0 ng/mL,89例),比较不同SF水平组患者SUA水平、HUA患病率的差异。根据是否合并HUA将T2DM患者分为HUA组(54例)和非HUA组(297例),比较两组之间SF水平及高铁蛋白血症患病率的差异。采用Pearson相关、Spearman秩相关及多元线性回归模型分析T2DM患者SF与SUA之间的相关性,采用二元logistic回归模型分析T2DM患者HUA发生的影响因素。结果T2DM患者q4组SUA水平[(344.54±105.94)μmol/L]高于q1组[(308.34±79.60)μmol/L,P0.05)。HUA组SF水平[174.50(105.40,295.25)ng/mL]高于非HUA组[129.00(69.55,226.00)ng/mL],差异有统计学意义(P0.05)。相关性分析提示SUA与SF呈正相关(rs=0.110,P=0.040)。多元线性回归分析提示T2DM患者SF与SUA呈独立正相关(P<0.05)。二元logistic回归分析提示T2DM患者SF与HUA呈独立正相关(OR=1.003,P=0.023)。结论T2DM患者SF水平与SUA密切相关,SF是T2DM患者HUA发生的独立影响因素。

关键词： 2型糖尿病血清铁蛋白血尿酸高尿酸血症

Preparation and growth mechanism of nickel nanowires under applied magnetic field

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Nano-Micro Letters 2010年第2期2卷 134-138页

作者： j.Wang L.Y.Zhang P.liu T.M.Lan j.Zhang L.M.Wei Eric Siu-Wai Kong C.H.jiang Y.F.Zhang National Key Laboratory of Nano/Micro Fabrication Technology Key Laboratory for Thin Film and Microfabrication of the Ministry of Education Institute of Micro and Nano Science and Technology Shanghai Jiao Tong University School of Materials Science and Engineering Shanghai Jiao Tong University Zhongyuan University of Technology

Nickel nanowires with large aspect ratio of up to 300 have been prepared by a hydrazine hydrate reduction method under applied magnetic field. The diameter of nickel nanowires is about 200 nm and length up to 60 μm. The role of magnetic field on the growth of magnetic nanowires is discussed and a magnetic nanowire growth mechanism has been proposed. Nickel ions are firstly reduced to nickel atoms by hydrazine hydrates in a strong alkaline solution and grow into tiny spherical nanoparticles. Then, these magnetic particles will align under a magnetic force and form linear chains. Furthermore, the as-formed chains can enhance the local magnetic field and attract other magnetic particles nearby, resulting finally as linear nanowires. The formation and the size of nanowires depend strongly on the magnitude of applied magnetic field.

关键词： Nanowire growth mechanism Nickel nanowires Magnetic-field assisted synthesis

Studies on Diversity of Leaf Morphological Traits of Plants Regenerated from ＂Miniature Seeds＂ in Loquat

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journal of Agricultural Science and Technology 2011年第1期5卷 116-120页

作者： L.Tao Y. q. Wang j. Yan q.X. Deng R. Z. Gu N. Luo College of Horticulture Sichuan Agricultural University Ya＇an 625014 Sichuan China

The genetic diversity of 79 accessions regenerated from ＂miniature seeds＂ of loquat （Eriobotrya japonica Lindl. cv. ＇Dawuxing＇） was analyzed based on 13 morphological characteristics of leaves in this study, in order to provide important morphological basis for breeding new varieties and materials through ＂miniature seed＂ breeding method in loquat. The results showed that there was abundant genetic diversity in leaf morphological characteristics of regenerated plants （D=0.785）, especially indicated by diversity indexes of leaf length （D=0.991）, leaf width （D=0.994）, petiole length （D=0.982）, petiole thickness （D=0.995） and leaf thickness （D=0.987）. And all the characteristic values varied broadly with coefficients of variation ranging from 9.84% to 40.09%; 79 accessions were divided into 6 groups by UPGMA method, there were significant differences in leaf morphological traits among the 6 groups; Group I and group VI were quite different from other groups and parent plants （cv. ＂Dawuxing＂）. The leaves of group I were darkgreen, large, hard and thick with long and thick petioles; while those of group VI were yellowgreen, small, thin and soft with slender petioles. These two groups were important excellent germplasm. Based on the abundant genetic diversity in leaf morphological characteristics, the breeding via ＂miniature seeds＂ was considered as an efficient method for broadening the germplasm resources and breeding new varieties of loquat.

关键词： Eriobotryajaponica Lindl genetic diversity leaf morphology miniature seed.

Conditional knockout tools: Application of site-specific incorporation of unnatural amino acid via genetic code expansion in viral and parasite vaccine development

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Synthetic and Systems Biotechnology 2017年第1期2卷 2-4页

作者： Pinghua liu Lubin jiang Department of Chemistry Boston UniversityBostonMA 02215USA Institut Pasteur of Shanghai(IPS) Chinese Academy of Sciences(CAS)Shanghai 200031PR China

Recently,Si et *** their attempts on generating live,while replication-incompetent influenza virus vaccine[1]as an alternative to inactivated and attenuated virus *** goal is to make use of the full infectivity of live whole-viron vaccine to elicit protective immunity while remaining as avirulent as *** this report,the authors explored the application of the sitespecific incorporation of unnatural amino acid approach[2,3]as a conditional knockout *** this method,a pair of tRNA-tRNA synthetase using one of the stop codons to encode for an unnatural amino acid of interest was *** tRNA-tRNA synthetase pair is orthogonal to all of the other tRNA-tRNA synthetase pairs in the host cell to ensure the site-specific incorporation of the unnatural amino acid of interest(Fig.1).One of the concerns is that the prematural stop codon used for encoding the unnatural amino acid might also be the natural stop codon for some of the host *** a result,introducing such tRNA-tRNA synthetase pair and the supplementation of the corresponding unnatural amino acid might impair the functions of the host cell *** select a proper cell line for viral packaging,the author integrated the Methanosarcinabarkeri MS pyrolysyl tRNA synthetase/tRNACUA pair,and an amber suppressor codon containing green fluorescent protein gene into the Human embryonic kidney(HEK)293T cell *** 200 generations of passage by selecting the unnatural amino acid dependent GFP production,the authors obtained a cell line that can mediate influenza A/WSN/33(H1N1:WSN)viral packaging in an efficiency as good as in the parental cells.

关键词： expansion selecting generating

An Easily Implementable Algorithm for Efficient Projection onto the Ordered Weighted l_(1)Norm Ball

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journal of the Operations Research Society of China 2023年第4期11卷 925-940页

作者： Yong-jin liu jia-jing Xu Lan-Yu Lin School of Mathematics and Statistics Fuzhou UniversityFuzhou350108FujianChina

This paper concerns with efficient projection onto the ordered weighted l_(1)norm ball,which is equivalent to the problem of finding projector onto the intersection of the monotone nonnegative cone and an affine *** on Lagrangian relaxation and secant approximation method,we propose an easily implementable yet efficient algorithm to solve the projection problem which is proved to terminate after a finite number of ***,we design efficient implementations for our algorithm and compare it with a semismooth Newton(SSN)algorithm and a root-finding(Root-F)*** results on a diversity of test problems show that our algorithm is superior than SSN and Root-F.

关键词： Lagrangian relaxation secant method ordered weighted l_(1)norm ball

激光功率对AlCoCrFeNi2.1高熵合金涂层组织与性能影响

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材料热处理学报 2024年第8期45卷 183-194页

作者：冉启科徐峰王波刘文义景然李凡可陕西理工大学材料科学与工程学院陕西汉中723000 西安重装蒲白煤矿机械有限公司陕西渭南715500

利用激光熔覆技术在q235钢基体表面制备了AlCoCrFeNi2.1高熵合金涂层,研究了激光功率对涂层组织和性能的影响。通过X射线衍射仪(XRD)、扫描电镜(SEM)、能谱仪(EDS)、维氏显微硬度计、摩擦磨损试验机和电化学工作站等对AlCoCrFeNi2.1高... 详细信息

利用激光熔覆技术在q235钢基体表面制备了AlCoCrFeNi2.1高熵合金涂层,研究了激光功率对涂层组织和性能的影响。通过X射线衍射仪(XRD)、扫描电镜(SEM)、能谱仪(EDS)、维氏显微硬度计、摩擦磨损试验机和电化学工作站等对AlCoCrFeNi2.1高熵合金涂层的显微组织、物相、力学性能及耐蚀性能进行了分析。结果表明:激光熔覆制备的AlCoCrFeNi2.1高熵合金涂层的组织由体心立方(BCC)结构和面心立方(FCC)结构的固溶体相构成;当激光功率大于1200 W时,涂层中BCC(α-Fe)固溶体相逐渐增多,晶粒由等轴晶和柱状树枝晶逐渐转变为细小的等轴晶;随着激光功率的增加,涂层的硬度呈现出先增加后降低的趋势;当激光功率1600 W时,涂层的硬度最大,为403.6 HV0.2,约为基体的2.5倍,此时涂层的耐磨性能达到最优,其磨损率为0.39×10^(-5) g·N^(-1)·m^(-1),自腐蚀电流密度最小,为5.23×10^(-9 )A·cm^(-2),耐腐蚀性能最好。

关键词： AlCoCrFeNi2.1高熵合金微观组织耐磨性耐腐蚀性