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Endogenous nitric oxide mediates alleviation of cadmium toxicity induced by calcium in rice seedlings

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Journal of Environmental Sciences 2012年第5期24卷 940-948页

作者： Long Zhang zhen Chen cheng Zhu State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang UniversityHangzhou 310058China College of Life Sciences China Jiliang UniversityHangzhou 310018China School of Life Sciences Taizhou UniversityTaizhou 317000China

The effect of calcium chloride （CaCl2） on rice seedling growth under cadmium chloride （CdCl2） stress, as well as the possible role of endogenous nitric oxide （NO） in this process, was studied. The growth of rice seedlings was seriously inhibited by CdCl2, and the inhibition was significantly mitigated by CaCl2. However, hemoglobin （Hb） and 2-（4-carboxyphenyl）-4, 4,5,5-tetramethylimidazoline- l-oxyl-3-oxide （cPTIO） weakened the promotion effect of CaCl2. The results of NO fluorescence localization suggest that growth accelerated by CaCl2 might be associated with elevated NO levels. The content of Cd, protein thiols （PBT）, and nonprotein thiols （NPT） in cell walls, cell organelles, and soluble fractions, respectively, of rice seedlings decreased considerably in the presence of CaCl2, whereas the content of pectin, hemicellulose 1 （HC1）, and hemicellulose 2 （HC2） increased significantly. Elimination of endogenous NO in Cd＋Ca treatment could promote the transportation of Cd2＋ to cell organelles and soluble fractions and increase the content of NPT and PBT in leaves. In addition, transportation of Cd2＋ to cell organelles and soluble fractions was retarded in roots, the content of NPT increased, and the content of PBT decreased. With elimination of endogenous NO in Cd＋Ca treatment, the content of pectin, HC1, and HC2 decreased significantly. Thus, Ca may alleviate Cd toxicity via endogenous NO with variation in the levels of NPT, PBT, and matrix polysaccharides.

关键词： nitric oxide cadmium calcium nonprotein thiols protein thiols matrix polysaccharides

In situ observation and modeling of austenite grain growth in a Nb-Ti-bearing high carbon steel

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Journal of Iron and Steel Research International 2019年第3期26卷 292-300页

作者： Guang Ji xiu-hua Gao zhen-guang Liu Ke Zhang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Jiangsu Shagang Group Huaigang Special Steel Co. Ltd.Huaian 223002JiangsuChina School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina Institute of Research of Iron and Steel ShasteelZhangjiagang 215625JiangsuChina

In situ measurements of austenite grain growth were made at various temperatures in the range of 1273-1473 K with subsequent isothermal holding time of 3600 s for the Nb-Ti-bearing and Nb-Ti-free high carb on steel by using a confocal laser scanning *** solid solute behavior of Nb-Ti carbides during austenitizing process was *** experimental results indicate that the austenite grains of both steels grow up gradually with increasing the heating temperature and holding time;the size and growth rate of austenite grain of Nb-Ti-bearing high carbon steel are much lower than those of Nb-Ti-free high carbon steel.A large amount of(Nb,Ti)(C,N)nanoparticles are observed in Nb-Tibearing steel,which retain the strong pinning effect on austenite grain *** kinetics model of austenite grain growth of Nb-Ti-bearing steel during isothermal heat treatment is obtained and the predicted values calculated by using the model meet the experimental values very well.

关键词： Con focal laser scanning microscope Nb-Ti microalloying High carb on steel Grain growth Nanoparticle Grain growth model

Simutaneous radar imaging and velocity measuring with step frequency waveforms

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Journal of Systems Engineering and Electronics 2009年第4期20卷 741-747页

作者： Yuan Haotian Wen Shuliang cheng zhen Beijing Inst. of Radio Measurement Beijing 100854 P. R. China

The principle and method of both radar target imaging and velocity measurement simultaneously based on step frequency waveforms is presented. Velocity compensation is necessary in order to obtain the good High resolution range profile since this waveform is greatly sensitive to the Doppler shift. The velocity measurement performance of the four styles is analyzed with two pulse trains consisted of positive and negative step frequency waveforms. The velocity of targets can be estimated first coarsely by using the pulse trains with positive-positive step frequency combination, and then fine by positive-negative combination. Simulation results indicate that the method can accomplish the accurate estimation of the velocity with efficient computation and good anti-noise performance and obtain the good HRRP simultaneously.

关键词： high resolution radar step frequency waveform velocity measuring high resolution range profile.

Experimental and numerical investigation of failure mode in geometrically imperfect DP590 steel

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Science China(Technological Sciences) 2015年第3期58卷 476-484页

作者： ZHUANG XinCun XU cheng ZHAO zhen Institute of Forming Technology & Equipment School of Materials Science and Engineering Shanghai Jiaotong University

Various microstructure-level finite element models were generated according to the real microstructure of DP590 steel to capture the mechanical behavior and fracture *** failure mode of the dual-phase(DP)steels,mainly resulting from microstructure-level inhomogeneity and initial geometrical imperfection,was predicted using the plastic strain localization *** addition,dog-bone-type tensile test specimens with different edge qualities were prepared and the deformation processes were recorded using a digital image correlation *** the steel exhibited no initial geometrical imperfection,void initiation was triggered by decohesion between martensite and ferrite which was predicted based on the severe strain concentration,or tensile stress in areas where stress triaxiality and strain values were *** failure was caused by shear localization in the ***,the initial geometrical imperfections severely affected the overall ductility and failure mode of the *** initial geometrical imperfections were deeply ingrained,an incipient crack began at the site of initial geometrical imperfection,and then caused progressive damage throughout the microstructure,from the area of shear localization to the final ***,the depth of the geometrical imperfection was the critical factor in determining whether internal decohesion or a local crack plays a dominant role.

关键词： representative volume element dual-phase(DP) steel geometrical imperfection failure mode

Ni@N-doped graphene nanosheets and CNTs hybrids modified separator as efficient polysulfide barrier for high-performance lithium sulfur batteries

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Nano Research 2019年第4期12卷 829-836页

作者： Xintao Zuo Mengmeng zhen cheng Wang Tianjin Key Laboratory of Advanced Functional Porous Materials and Center far Electron Microscopy Institute far New Energy Materials & Low-Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology Tianjin 300071 China Tianjin Key Laboratory of Clean Energy and Pollution Control School of Energy and Environmental Engineering Hebei University of Technology Tianjin 300401 China

Lithium-sulfur batteries (LSBs) have been regarded as one of the most promising energy storage systems to break through the upper limit of lithium-ion ***,the rampant diffusions of soluble lithium polysulfides (LiPSs) in the electrolyte induced the shuttle effect between anode and cathode,resulting in low sulfur utilization,low energy efficiency and short cycling ***,we prove the rational design and construction of Ni nanoparticles filled in vertically grown N-doped bamboo-like carbon nanotubes (CNTs) on graphene nanosheets (Ni@NG-CNTs) as efficient polysulfide barrier for high-performance *** unique design integrates graphene nanosheets and CNTs into hierarchical architectures with one-dimensional (1D) CNTs,two-dimensional (2D) ultrethin nanosheets and abundant carbon *** design provides large surface area for lithium polysulfides (LiPSs) adsorption,accelerates electron transport and enhances electrochemical redox of *** from the unique structural features,the LSBs with the Ni@NG-CNTs as polysulfide barrier keep high reversible specific capacities of 309.1 and 265.0 mAh·g-1 at 5 and 10 C rates after 500 *** work provides a new strategy for constructing self-assembled hybrids of CNTs and graphene nanosheets with abundant carbon nanocages for high-performance LSBs.

关键词： lithium-sulfur batteries self-assembled hierarchical architecture confined Ni nanoparticles abundant carbon nanocages modified separator

上海市长宁区虹桥街道社区卫生服务中心家庭病床服务现状分析

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中国初级卫生保健 2025年第1期39卷 14-17页

作者：葛臻程頲上海市长宁区虹桥街道社区卫生服务中心上海200051

目的:通过对上海市长宁区虹桥街道社区卫生服务中心家庭病床患者服务现状进行调查分析,以探讨家庭病床服务在社区养老体系中的作用与现状。方法:采用回顾性调查方法,对2020—2023年虹桥街道社区卫生服务中心建立的家庭病床情况进行调查... 详细信息

目的:通过对上海市长宁区虹桥街道社区卫生服务中心家庭病床患者服务现状进行调查分析,以探讨家庭病床服务在社区养老体系中的作用与现状。方法:采用回顾性调查方法,对2020—2023年虹桥街道社区卫生服务中心建立的家庭病床情况进行调查。结果:2020—2023年虹桥街道社区卫生服务中心家庭病床数分别为465张、498张、324张、446张,共计1 733张,建床数除了2022年因疫情原因明显下降外,其他年份建床数增幅在6.4‰~7.2‰之间;中医床位数分别为158张、187张、116张、151张,中医床位数占比均在30%以上。家庭病床患者年龄为52~103岁,中位年龄为88.5岁;以慢性病患者为主,高血压患者占比最高(40.8%),其次为心血管疾病患者(30.8%)和脑血管病患者(12.6%),此外居家安宁疗护患者占2.3%。虹桥街道社区卫生服务中心家庭病床医生共15人、护理人员8人,均为兼职开展家庭病床工作。结论:家庭病床服务在慢性病管理中扮演着重要角色,未来还需要通过完善相应的法律法规、加快专业人才队伍的建设、完善对医务人员的激励机制、不断创新和拓展服务内容等方式进一步完善和促进家庭病床服务全面发展。

关键词：家庭病床社区养老基层社区

Syntheses, Structures and Fluorescent Properties of Two 1D Chain Organic Amines and Metal Iodine Organic-inorganic Hybrid Compounds

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Chinese Journal of Structural Chemistry 2019年第2期38卷 284-292,168页

作者： YOU xiu-Li WEI zhen-Hong Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal University College of Chemistry Nanchang University

Two bifunctional amines, 4-(2-aminoethyl)morpholine and histamine, were heated with PbI_2 and BiI_3 in concentrated HI aqueous solution to give one-dimensional(1D) organicinorganic hybrid compounds [(C_6H_(16)N_2O)PbI4]n(1) and [(C_(16)H_(20)N_(20))Bi_2I_(10)](2), respectively. In 1, the [PbI6] octahedra formed double chain anions through sharing-corner and-edge, and the protonated(C_6H_(16)N_2O)^(2+) cations were located at the vicinity of the double chains by hydrogen bonds. In 2, the [BiI_6] octahedra firstly formed dimeric [Bi_2I_(10)]^(4-) anion through sharing edge, and subsequently, the protonated histamine cations worked as bridge to link alternately with [Bi_2I_(10)]^(4-) anion by hydrogen bonds to form organic-inorganic hybrid 1D chains. In addition, compound 1 emitted a green light at the excitation wavelength of 400 nm and the maximum emission wavelength is at 503 nm.

关键词： organic-inorganic hybrids bifunctional amines metal iodide crystal structure fluorescent property

STRATEGIC ENVIRONMENTAL ASSESSMENT FOR SUSTAINABLE DEVELOPMENT IN URBANIZATION PROCESS IN CHINA

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Chinese Geographical Science 2004年第2期14卷 148-152页

作者： CHExiu-zhen SHANGJin-cheng ShenzhenInstituteofEnvironmentalScience Shenzhen518008P.R.China EnvironmentalScienceResearchInstitute NortheastNormalUniversityChangchun130024P.R.China

This paper reviewed the development of Strategic Environmental Assessment (SEA) in China, expounded its functions and regional characteristics, and discussed the targets of SEA in the process of urbanization,and the main assessment indicators, procedures, techniques and methodologies of SEA. It concluded that SEA could be improved by the following recommendations: incorporating SEA in decision-making process, selecting experimental units for SEA trial run, and developing strategic evaluation tools and techniques. SEA can provide appropriate and up-to-date information on the impact of human activity on environment in the process of urbanization, and develop a plan of action targeting implementation of intervention for the rehabilitation and preservation of the ecological stability of a city. Therefore, SEA can be a supporting tool for decision-making toward achieving sustainable development.

关键词： Strategic Environmental Assessment urbanization sustainable development environmental decision-making

Unified Classification and Rejection:A One-versus-all Framework

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Machine Intelligence Research 2024年第5期21卷 870-887页

作者： zhen cheng Xu-Yao Zhang cheng-Lin Liu State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing100049China

Classifying patterns of known classes and rejecting ambiguous and novel(also called as out-of-distribution(OOD))inputs are involved in open world pattern *** neural network models usually excel in closed-set classification while perform poorly in rejecting OOD *** tackle this problem,numerous methods have been designed to perform open set recognition(OSR)or OOD rejection/detection *** methods mostly take post-training score transformation or hybrid models to ensure low scores on OOD inputs while separating known *** this paper,we attempt to build a unified framework for building open set classifiers for both classification and OOD *** formulate the open set recognition of K-known-class as a(K+1)-class classification problem with model trained on known-class samples *** decomposing the K-class problem into K one-versus-all(OVA)binary classification tasks and binding some parameters,we show that combining the scores of OVA classifiers can give(K+1)-class posterior probabilities,which enables classification and OOD rejection in a unified *** maintain the closed-set classification accuracy of the OVA trained classifier,we propose a hybrid training strategy combining OVA loss and multi-class cross-entropy *** implement the OVA framework and hybrid training strategy on the recently proposed convolutional prototype network and prototype classifier on vision transformer(ViT)*** on popular OSR and OOD detection datasets demonstrate that the proposed framework,using a single multi-class classifier,yields competitive performance in closed-set classification,OOD detection,and misclassification *** code is available at https://***/zhen-cheng121/CPN_OVA_unified.

关键词： Open set recognition out-of-distribution detection misclassification detection convolutional prototype network oneversus-all Dempster-Shafer theory of evidence