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生物化学与生物物理学报 1999年第6期31卷 689-694页

作者：钱友存范春阳刘小龙胡泰山杨胜利龚毅中国科学院上海生物工程研究中心!上海200233 中国科学院上海生物化学研究所!上海200031

从银环蛇毒腺中抽提总ＲＮＡ，ＲＴＰＣＲ扩增编码β银环蛇毒素Ａ链的ｃＤＮＡ，克隆并测定了全序列。一个新的ｃＤＮＡ得以克隆，其编码一个２７个氨基酸的信号肽和一个１２０个氨基酸的成熟蛋白。该成熟蛋白和其他β银环蛇... 详细信息

从银环蛇毒腺中抽提总ＲＮＡ，ＲＴＰＣＲ扩增编码β银环蛇毒素Ａ链的ｃＤＮＡ，克隆并测定了全序列。一个新的ｃＤＮＡ得以克隆，其编码一个２７个氨基酸的信号肽和一个１２０个氨基酸的成熟蛋白。该成熟蛋白和其他β银环蛇毒素Ａ链一样，具有１３个位置固定的半胱氨酸，而且和这些Ａ链具有很高的同源性。此外，以同样的引物，从眼镜蛇毒腺总ＲＮＡ中，克隆到编码眼镜蛇ＰＬＡ２前体的ｃＤＮＡ。将β银环蛇毒素Ａ链和眼镜蛇ＰＬＡ２的ｃＤＮＡ亚克隆到表达载体ｐＭＡＬｐ２上，转化大肠杆菌ＢＬ２１菌株。两种蛋白质在大肠杆菌中得到高效的可溶性融合蛋白。通过亲和层析纯化这两种融合蛋白。经Ｘａ因子酶切得到的重组眼镜蛇ＰＬＡ２和β银环蛇毒素Ａ链分别具有较强和较弱的磷脂酶Ａ２活性。

关键词： β-银环蛇毒素A链 cDNA克隆融合表达磷脂酶A2活性

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广西佛子冲广平岩体成因及地质意义

矿物岩石 2016年第4期36卷 86-94页

作者：王泰山杨启军鲁海峰林艳海周辉张鑫利余福承陈秉芳徐贝贝青海省青藏高原北部地质过程与矿产资源重点实验室青海西宁810012 青海省地质调查院青海西宁810012 桂林理工大学地球科学学院广西桂林541004 广西地质调查院广西南宁530021

针对佛子冲地区产出的正长花岗岩进行锆石LA-ICP-MS锆石U-Pb同位素年代学研究,结果表明,该岩体的形成年龄为170.8 Ma±6.3 Ma,时代为中侏罗世。岩石地球化学研究表明该岩石具有高钾钙碱性特征(K_2O+Na_2O=8.64%~9.62%,σ=2.44~2.69),准... 详细信息

针对佛子冲地区产出的正长花岗岩进行锆石LA-ICP-MS锆石U-Pb同位素年代学研究,结果表明,该岩体的形成年龄为170.8 Ma±6.3 Ma,时代为中侏罗世。岩石地球化学研究表明该岩石具有高钾钙碱性特征(K_2O+Na_2O=8.64%~9.62%,σ=2.44~2.69),准铝—弱过铝质(A/CNK=1.01~1.04),稀土含量高(ΣREE=273×10^(-6)~439×10^(-6),平均323×10^(-6)),LREE强烈富集,HREE轻度富集(La/Yb)N=10.87~16.21,平均13.68),较强的Eu负异常(δEu=0.18~0.26),总体呈向右缓倾斜的海鸥式,微量元素蛛网图上出现强烈富集Rb,Th,U,Pb,而亏损Ba,Sr,P,Ti,Eu,结合花岗岩成因类型判别图解确定其为A型花岗岩。综合区域上的研究成果,佛子冲中侏罗世正长花岗岩进一步佐证了华南地区在侏罗纪时,岩石圈发生了伸展作用,区域上是太平洋板块向西俯冲的一个地质响应。

关键词：佛子冲锆石U-Pb年龄岩石地球化学 A型花岗岩伸展作用

Near-Threshold Wide-Voltage Design Review

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Tsinghua Science and Technology 2023年第4期28卷 696-718页

作者： Yan Zhao Jun yang Chao Chen Weiwei shan Peng Cao Yongliang Zhou Ziyu Li tai yang National Application Specific Integrated Circuit(ASIC)Center Southeast UniversityNanjing 210096China

This paper presents a comprehensive review of near-threshold wide-voltage designs on memory,resilient logic designs,low voltage Radio Frequency(RF)circuits,and timing *** the prosperous development of wearable applications,low power consumption has become one of the primary challenges for IC *** improve the power efficiency,the prefer scheme is to operate at an ultra low voltage of Near Threshold Voltage(NTV).For the performance variation and degradation,a self-adaptive margin assignment technique is proposed in the low *** proposed technique tracks the circuit states in real time and dynamically allocates voltage margins,reducing the minimum supply voltage and achieving higher energy *** self-adaptive margin assignment technique can be used in Static Random Access Memory(SRAM),digital circuits,and analog/RF *** on the self-adaptive margin assignment technique,the minimum voltage in the 40 nm CMOS process is reduced to 0.6 V or even lower,and the energy efficiency is increased by 3–4 times.

关键词： Near Threshold Voltage(NTV) wide-voltage memory resilient logic design low voltage Radio Frequency(RF) timing analysis

Two New Diterpenes from Helianthus annuus L.

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Chinese Chemical Letters 2006年第1期17卷 45-48页

作者： Mao Rong SUO Jun shan yang yang LU Li WU Qi tai ZHENG Institute of Medicinal Plant Development Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100094 Institute of Medicinal Materia Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050

Two new diterpenes, 2β, 16β-ent-kaurane diol, 15α, 16α-epoxy-17β-al-ent-kaurane- 19-oic acid were isolated from Helianthus annuus L. Their structures were determined by spectroscopic evidences.

关键词： Helianthus annuus diterpene.

Asymptotic Behavior of Solutions to a Class of Systems of Delay Differential Equations

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Acta Mathematica Sinica,English Series 2007年第8期23卷 1375-1384页

作者： tai shan YI Li Hong HUANG College of Mathematics and Econometrics. Hu'nan University Changsha Hu'nan 410082 P. R. China

The authors investigate the asymptotic behavior of solutions to a class of systems of delay differential equations. It is shown that every bounded solution of such a class of systems tends to a constant vector as t→... 详细信息

关键词： asymptotic behavior delay differential equation ω-limit set

Use of chlorophyll fluorescence and P700 absorbance to rapidly detect glyphosate resistance in goosegrass(Eleusine indica)

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Journal of Integrative Agriculture 2015年第4期14卷 714-723页

作者： ZHANG tai-jie FENG Li TIAN Xing-shan yang Cai-hong GAO Jia-dong Institute of Plant Protection Guangdong Academy of Agricultural Sciences/Guangdong Provincial Key Laboratory of High Technology for Plant Protection

The rapid detection of glyphosate resistance in goosegrass（Eleusine indica） will enhance our ability to respond to new resistant populations of this major weed. Chlorophyll fluorescence（Fluo） and P700（reaction center chlorophyll of photosystem I） absorbance were analyzed in one biotype of goosegrass that is resistant to glyphosate and in another that remains sensitive to the herbicide. Both biotypes were treated with a foliar spray of glyphosate. Differences in photosystem II maximum quantum yield（Fv/Fm）, effective photochemical quantum yield（Y（II））, and non-photochemical quenching（NPQ） between the biotypes increased over time. Values for Fv/Fm and Y（II） differed between the two biotypes 24 h after treatment（HAT）. Differentiated activities and energy dissipation processes of photosystem II（PSII） and energy dissipation processes of photosystem I（PSI） were manifested in the two biotypes 24 HAT with 20 mmol L–1 glyphosate. Differentiated energy dissipation processes of PSI were still apparent 24 HAT with 200 mmol L–1 glyphosate. These results indicate that the Fluo parameters related to PSII activity and energy dissipation and the P700 parameters related to energy dissipation are suitable indicators that enable rapid detection of glyphosate resistance in goosegrass.

关键词： Eleusine indica glyphosate resistance chlorophyll fluorescence P700

Tetracycline removal by a magnetic heterojunction Cu_(2)O/CoFe_(2)O_(4) activating peroxymonosulfate

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Rare Metals 2023年第3期42卷 862-874页

作者： Xiao-Qing Li shan Feng Jun yang tai-Ping Xie Jian-Kang Wang Xiao-Jing Chen De-Shun Kong Hou-yang Chen Department of Chemical Engineering Chongqing Chemical Industry Vocational CollegeChongqing 401228China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Environmental Materials and Remediation Technologies College of Chemical and Environmental EngineeringChongqing University of Arts and SciencesYongchuan 402160China School of Materials Science and Engineering Yangtze Normal UniversityChongqing 408100China School of Mining and Civil Engineering Liupanshui Normal UniversityLiupanshui 553004China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

The electron transfer mechanism in the process of peroxymonosulfate(PMS)activation using heterojunction catalyst was *** this work,magnetic heterojunction Cu_(2)O/CoFe_(2)O_(4)(CC)was first synthesized to activate *** innovative reaction mechanism based on built-in electric field-driven electron migration from Cu2O to CoFe2O4 and effective magnetic moment of CC for enhancing PMS activation was ***,the CC/PMS system was used for efficient removal of antibiotic tetracycline(TC).Under optimal conditions,98.0%TC could be removed using CC/PMS catalytic system after only 30 *** catalytic activity was higher than that of Cu_(2)O/PMS and CoFe_(2)O_(4)/***,the impact of solution pH on TC removal was insignificant,suggesting the pH-insensitive PMS activation ability of ***,the coexisting inorganic ions in the environment,such as HCO_(3)-,H_(2)PO4-,NO_(3)-,Cl-and humic acid(HA)as representative of natural organic matter,did not inhibit TC removal in CC/PMS ***,CC/PMS system exhibited excellent reusability with more than94.0%TC removal after the 5th *** paramagnetic resonance(EPR)tests and quenching experiments showed that O_(2)·-and 1O_(2) played vital roles in TC *** intermediate products and corresponding toxicity assessment revealed that this catalytic system could reduce TC *** work provided new insights into the PMS activation mechanism using heterogeneous magnetic catalysts,including transition metal oxide.

关键词： Peroxymonosulfate(PMS)activation Heterojunction catalyst Electron migration Cu2O CoFe204

Experimental study on ceramic balls impact composite armor

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Defence Technology（防务技术） 2020年第2期16卷 408-416页

作者： Wei-zhan Wang Zhi-gang Chen Shun-shan Feng tai-yong Zhao Underground Target Damage Technology National Defense Key Discipline Laboratory North University of ChinaTaiyuan 030051ShanxiChina State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology100081BeijingChina

Ceramic balls represent a new type of damaging element,and studies on their damaging power of composite armor are required for a comprehensive evaluation of the effectiveness of various types of *** goal of this study was to determine the impact ofφ7 mm toughened Al2 O3 ceramic balls on a composite ceramic/metal *** influences of the ceramic panel and the thickness of the metal backing material on the destroying power of the ceramic balls were first *** on the agreement between numerical simulation,experimental results,and calculation models of the target plate resistance,the response mechanism of the ceramic balls was further *** results indicate that for a back plate of Q235 steel,with an increasing thickness of the ceramic panel,the piercing speed limit of the ceramic balls gradually increases and the diameter of the out-going hole on the metal back *** conditions were tested to assess the effects on the piercing speed,the diameter of the out-going hole,the micro-element stress,and the integrity of the recovered ceramic bowl.

关键词： Impact Penetration Infinitesimal Interface collapse

High-resolution ARPES endstation for in situ electronic structure investigations at SSRF

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Nuclear Science and Techniques 2021年第3期32卷 94-106页

作者： Yi-Chen yang Zheng-tai Liu Ji-shan Liu Zhong-Hao Liu Wan-Ling Liu Xiang-Le Lu Hong-Ping Mei Ang Li Mao Ye shan Qiao Da-Wei Shen State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China University of Chinese Academy of Sciences Beijing 100049China

Angle-resolved photoemission spectroscopy(ARPES)is one of the most powerful experimental techniques in condensed matter *** ARPES,which uses photons with high flux and continuously tunable energy,has become particularly ***,an excellent synchrotron ARPES system must have features such as a small beam spot,super-high energy resolution,and a user-friendly operation interface.A synchrotron beamline and an endstation(BL03 U)were designed and constructed at the shanghai Synchrotron Radiation *** beam spot size at the sample position is 7.5(V)μm×67(H)μm,and the fundamental photon range is 7-165 eV;the ARPES system enables photoemission with an energy resolution of 2.67 meV at21.2 *** addition,the ARPES system of this endstation is equipped with a six-axis cryogenic sample manipulator(the lowest temperature is 7 K)and is integrated with an oxide molecular beam epitaxy system and a scanning tunneling microscope,which can provide an advanced platform for in situ characterization of the fine electronic structure of condensed matter.

关键词： Synchrotron ARPES In situ VUV laser Quantum materials