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Fluoride in Tea and Its Risk Assessment

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茶叶 2013年第4期39卷 515-518页

作者： Li NN Liang YR zheng xq Zhejiang University Tea Research Institute

Tea plant absorbs from soil a large amount of fluorine(F) which is accumulated in leaf,resulting in elevated F concentration in *** is a controversial topic whether the fluoride in tea is associated with *** research advances in F variation of various kinds of tea,factors influencing F level in tea and the associated health risk assessment were reviewed in the present *** F level in tea increases with the maturity of the tea *** tea had a high F content because it was prepared using mature shoots and old tea leaves as raw *** low grade UK supermarket economy teas contained elevated F comparable to the Chinese brick *** F level is also affected by tea cultivar,soil condition,tea processing method and tea infusion preparation method.

关键词：健康风险评估茶叶经济氟中毒茶树品种土壤条件制备方法加工方法氟含量

Characteristics of atmospheric oscillation in the Prydz Bay region during the ozone hole period in 1993

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Chinese Science Bulletin 1997年第10期42卷 842-845页

作者： Lu, LH Zhou, XJ Bian, LG Zhang, xq zheng, XD Chinese Academy of Meteorological Sciences Beijing China

IN ref.[1],a preliminary analysis was reported on the change characteristics of total ozoneduring the Antarctic'ozone hole'period in 1993,revealing that there is a very obvious dailychange of total ozone over Zhongshan Station and suggesting that this change would be relatedto the position of Zhongshan Station on the rim of the ozone hole influenced by the polar vortexvacillation and the expanding and contracting processes in Antarctic *** this note,

关键词： Antarctic Prvdz Bay ozone hole atmospheric oscillation.

Current and future perspectives on the regulation and functions of miR-545 in cancer development

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Cancer Pathogenesis and Therapy 2024年第3期2卷 142-154页

作者： Jinze Shen Xinming Su Qurui Wang Yufei Ke Tianyu zheng Yunan Mao Zehua Wang Jingyin Dong Shiwei Duan Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province School of MedicineHangzhou City UniversityHangzhouZhejiang 310015China

Micro ribonucleic acids(miRNAs)are a highly conserved class of single-stranded non-coding *** the miR-545/374a cluster,miR-545 resides in the intron of the long non-coding RNA(lncRNA)FTX on *** precursor form,pre-miR-545,is cleaved to generate two mature miRNAs,miR-545-3p and ***,these two miRNAs exhibit distinct aberrant expression patterns in different cancers;however,their expression in colorectal cancer remains ***,miR-545-3p is affected by 15 circular RNAs(circRNAs)and 10 long non-coding RNAs(lncRNAs),and it targets 27 protein-coding genes(PCGs)that participate in the regulation of four signaling *** contrast,miR-545-5p is regulated by one circRNA and five lncRNAs,it targets six PCGs and contributes to the regulation of one signaling *** miR-545-3p and miR-545-5p affect crucial cellular behaviors,including cell cycle,proliferation,apoptosis,epithelial-mesenchymal transition,invasion,and *** low miR-545-3p expression is associated with poor prognosis in three cancer types,studies on miR-545-5p are yet to be ***-545-3p operates within a diverse range of regulatory networks,thereby augmenting the efficacy of cancer chemotherapy,radiotherapy,and ***,miR-545-5p enhances immunotherapy efficacy by inhibiting T-cell immunoglobulin and mucin-domain containing-3(TIM-3)*** summary,miR-545 holds immense potential as a cancer biomarker and therapeutic *** aberrant expression and regulatory mechanisms of miR-545 in cancer warrant further investigation.

关键词： miR-545 Competing endogenous RNA Cell behavior Biomarker Therapeutic drug Immunotherapy

Vitrificational cryopreservation and subsequently fertile plant regeneration from rice (Oryza sativa L.) embryogenic suspension cells

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Chinese Science Bulletin 1997年第5期42卷 422-426页

作者： Wang, JH zheng, Y Yan, QF Yan, QS Zhang, xq Huang, CN College of Life Science Hangzhou University Hangzhou China China National Rice Research Institute Hangzhou China

CRYOPRESERVATION by vitrification is a new ultralow-temperature-storage technique developed in the 1980s. Operationally, procedures for vitrification of biological specimens consist of the following basic steps: treatment of the samples in a highly concentrated vitrification solution and then plunging the specimens into liquid nitrogen. The word 'vitrification' is sometimes used to describe the high moisture of the in vitro cultures or regenerants. However, in this note, this word means a biophysical process in which the cells and the solution are transformed into a homogeneous and amorphous state. The water in cells does not change into ice, but in

关键词： rice embryogenic suspension cells vitrification cryopreservation plant regeneration.

Twelve-frame camera for soft X-ray

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Chinese Science Bulletin 1997年第14期42卷 1215-1217页

作者： Cheng, JX Yang, CB Wen, TS Wen, SH Tang, DY zheng, ZJ Shan, B Liu, JY Chang, ZH Liu, xq Gao, SC Institute of Nuclear Physics and Chemistry Chinese Academy of Engineering Physics Chengdu China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China

THE procedure of inertial confinement fusion (ICF) takes place in sub-nanosecond period. Inorder to investigate the hydrodynamic instability and asymmetry during the implosion, weneed to measure the two-dimensional distribution of plasmas temperature and density as well asits relationship with time. For this purpose, an X-ray picosecond multiframe technique hasbeen developed.

关键词： gated microchannel-plate picosecond frame microstrip line.

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礼遇文化观照下社区坐具设计策略

建材技术与应用 2024年第2期 75-80页

作者：肖瑜丁铮福州外语外贸学院艺术与设计学院福建福州350202 福建农林大学风景园林与艺术学院福建福州350002

基于大量的社区坐具使用现状调研和用户行为分析可知,当今社会社区坐具的设计存在造型功能单一、人性化设计缺失和文化内涵薄弱等问题。以传承和发展现代礼遇文化特色为基础,通过提出造型设计元素萃取、坐具需求全面分析和礼遇文化精准... 详细信息

基于大量的社区坐具使用现状调研和用户行为分析可知,当今社会社区坐具的设计存在造型功能单一、人性化设计缺失和文化内涵薄弱等问题。以传承和发展现代礼遇文化特色为基础,通过提出造型设计元素萃取、坐具需求全面分析和礼遇文化精准注入三个设计策略,解决社区坐具存在的主要问题,进而为社区坐具的设计提供新角度,也为礼遇文化在现代设计中的应用提供新思路。

关键词：礼遇文化社区坐具设计策略

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金属橡胶-聚氨酯复合材料减振性能研究

材料导报 2024年第6期38卷 267-273页

作者：郑孝源任志英吴乙万白鸿柏黄健萌谭桂斌福州大学机械工程及自动化学院金属橡胶与振动噪声研究所福州350116 广东工业大学机电工程学院广州510006

针对单一减振材料无法兼具高阻尼与高刚度的弊端,本工作提出了一种新的复合材料,即将三维空间网状结构的金属橡胶(EMWM)作为基体,聚氨酯(PU)作为增强体,并采用真空渗流的方式制备了具有高阻尼与高刚度的金属橡胶-聚氨酯(EMWM-PU)复合材... 详细信息

针对单一减振材料无法兼具高阻尼与高刚度的弊端,本工作提出了一种新的复合材料,即将三维空间网状结构的金属橡胶(EMWM)作为基体,聚氨酯(PU)作为增强体,并采用真空渗流的方式制备了具有高阻尼与高刚度的金属橡胶-聚氨酯(EMWM-PU)复合材料。通过EMWM与EMWM-PU复合材料的准静态压缩试验,发现界面摩擦的引入使得EMWM-PU复合材料的耗能与刚度特性得到显著提升。此外搭建了复合材料管路减振测试平台,以平均振动加速度级和插入损失作为评价指标,研究了EMWM密度、激振量级、安装时的预紧间距对管路减振性能的影响。结果表明,EMWM-PU复合材料在5~1 000 Hz频段范围内均具有优异的减振效果,且复合材料中基体材料EMEM的密度越小、安装时的预紧间距越大,减振效果越好。本研究有效拓宽了复合材料的应用范围,也为金属橡胶复合材料的设计和应用提供了有效的指导。

关键词：金属橡胶聚氨酯复合材料力学性能管路减振

Analytic Initial Relative Orbit Solution for Angles-Only Space Rendezvous Using Hybrid Dynamics Method

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 221-234页

作者： Baichun Gong Shuang Li Lili zheng Jinglang Feng Nanjing University of Aeronautics and Astronautics Nanjing210016China Beijing Institute of Aerospace System Engineering Beijing100076China University of Strathclyde GlasgowG11XQScotland

A closed-form solution to the angles-only initial relative orbit determination(IROD)problem for space rendezvous with non-cooperated target is developed,where a method of hybrid dynamics with the concept of virtual formation is introduced to analytically solve the *** is placed on developing the solution based on hybrid dynamics(i.e.,Clohessy-Wiltshire equations and two-body dynamics),obtaining formation geometries that produce relative orbit state observability,and deriving the approximate analytic error covariance for the IROD solution.A standard Monte Carlo simulation system based on two-body dynamics is used to verify the feasibility and evaluate the performance proposed *** sensitivity of the solution accuracy to the formation geometry,observation numbers is presented and discussed.

关键词： Space rendezvous relative orbit determination angles-only measurement covariance analysis

基于ADAMS的六轴搬运机器人动力学仿真分析

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闽江学院学报 2024年第2期45卷 21-29页

作者：翁伟郑祥盘唐晓腾福建信息职业技术学院智能制造学院福建福州350002 闽江学院物理与电子信息工程学院福建福州350108

以折弯生产线中上下料工序中所使用的六轴搬运机器人为例开展研究,首先确定了机器人的结构形式,设计了各关键零部件并建立了六轴搬运机器人的三维模型;其次基于ADAMS软件建立了搬运机器人的动力学仿真模型,对机器人的零部件材料、约束... 详细信息

以折弯生产线中上下料工序中所使用的六轴搬运机器人为例开展研究,首先确定了机器人的结构形式,设计了各关键零部件并建立了六轴搬运机器人的三维模型;其次基于ADAMS软件建立了搬运机器人的动力学仿真模型,对机器人的零部件材料、约束、驱动,以及载荷进行定义;最后通过对机器人进行动力学仿真模拟得到了机器人的基本运动数据。研究结果表明:所设计的搬运机器人6个轴的位移、速度、加速度、关节受力以及扭矩曲线基本上连续、无异变。六轴搬运机器人在运动过程中运动平稳、振荡较小、设计合理,为改进其结构提供了理论支撑。

关键词：六轴搬运机器人动力学建模动力学仿真分析 ADAMS