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Journal of Materials Science & Technology 2001年第2期17卷 197-202页

作者： Xiufeng HAN State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China Terunobu Miyazaki Department of Applied Physics, Graduate School of Engineering, Tohoku University, Aoba-yama 08, Sendai 980-8579, Japa State Key Lab. of Magnetism Inst. of Phys. Chinese Acad. of Sci. Beijing 100080 China

Temperature dependence of tunnel magnetoresistance (TMR) ratio. resistance, and coercivity from 4.2 K to room temperature (RT), applied dc bias voltage dependence of the TMR ratio and resistances at 4.2 K and RT. tunnel current I and dynamic conductance dI/dV as functions of the dc bias voltage at 4.2 K, and inelastic electron tunneling (IET) spectroscopy, d2I/dV2 versus V, at 4.2 K for a tunnel junction of Ta(5 nm)/Ni79 Fe21 (25 nm)/lr22 Mn78(12 nm)/Co75 Fe25(4 nm)/ Al(0.8 um)-oxide/Co75Fe25(4 nm)/Ni79Fe21(25 nm)/Ta(5 um ) were systematically investigated High TMR ratio of 59.2% at 4.2 K and 41.3% at RT were observed for this junction after annealing at 275’C for an hour. The temperature dependence of TMR ratio and resistances from 4.2 to 300 K at 1.0 mV bias and the dc bias voltage dependence of TMR ratio at 4.2 K from 0 to 80 mV can be evaluated by a comparison of self-consistent calculations with the experimental data based on the magnon-assisted inelastic excitation model and theory. An anisotropic wavelength cutoff energy of spin-wave spectrum in magnetic tunnel junctions (MTJs) was suggested, which is necessary for self-consistent calculations, based on a series of IET spectra observed in the MTJs.

关键词： off TMR A Self-consistent Calculation and an Anisotropic Wavelength Cut Energy of Spin-wave Spectrumin Magnetic Tunnel Junctions wave Figure than

High-Performance In0.23Ga0.77As Channel MOSFETs with High Current Ratio Ion/Ioff Grown on Semi-insulating GaAs Substrates by MOCVD

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Chinese Physics Letters 2015年第3期32卷 121-123页

作者：孔祥挺周旭亮李士颜乔丽君刘洪刚王圩潘教青 Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 Microwave Device and IC Department Institute of Microeleetronics Chinese Academy of Sciences Beijing 100029

We demonstrate high-performance In0.23 Ga0.77 As channel metal-oxide-semiconductor field-effect transistors （ MOS- FETs） with high on-current to off-current （Ion/Ioff） ratio grown on semi-insulating GaAs wafers by metal-organic chemical vapor deposition （MOCVD）. The 2μm channel-length devices exhibit a peak extrinsic transeonductance of 150 mS/mm and a drain current up to 500 mA/mm. The maximum effective mobility is 1680 cm2/Vs extracted by the split C-V method. Furthermore, the Ion/Ioff ratio is significantly improved from approximately 4.5 × 10^3 up to approximately 4.32 × 10^4 by controlling the etch thickness of In0.49Ga0.51P, The high drain current and high Ion/Ioff ratio of the In0.23Ga0.77As channel MOSFETs are achieved due to the high effective mobility and the low gate leakage current density.

关键词： As Channel MOSFETs with High Current Ratio I MOSFET Ga Grown on Semi-insulating GaAs Substrates by MOCVD off

Study　on　the　Methods　Of　Adsorbent　Enriching－SFE　Desorbing　and　off－line　GC－MS－DS　Determination　of　Trace　Organic　Pollutants　from　Coal　Smoke

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Chinese Chemical Letters 1996年第11期7卷 1061-1064页

作者： Cui, ZJ Gao, LC Zhang, CY Wang, SR SHANDONG UNIV DEPT ENVIRONM ENGNJINAN 250100PEOPLES R CHINA

The optimum conditions of supercritical fluid extraction(SFE) desorping the organic pollutants adsorbed and enriched by the adsorbent Porapak P and the effects of the conditions on the efficiencies ofSFE desorping organic pollutants are studied emphatically. Different kinds of organic adsorbents andmodifiers were tested. The recoveries of SFE are compared with Soxhlet extraction. The recoveries between93.1% and 109.3% are obtained for 25 kinds of compounds at 35 MPa, 100℃and 9.0ml SF-CO2, andtheir relative standard deviations (RSD) are in the range of 0.6-12.6 percent.

关键词： GC off MS line DS SFE

Turned off Characteristics of Linear Ultrasonic Motor

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第1期34卷 49-54页

作者： Zhang Jun Shi Yunlai Niu Zijie Liang Dazhi State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics College of Mechanical and Electronic Engineering Northwest Agriculture and Forestry University

The high controllability and high resolution control of linear ultrasonic motors depend on effective control of driving signals.For a good control characteristic,step control which the driver output turned off and on was used.Therefore,a novel dual PWM topology structure ultrasonic motor driver was designed and analyzed.According to the characteristics of the circuits,two kinds of hardware turned off methods named methods A and B were discussed.The differences of the voltage applied on motor by different methods were figured out.Finally,a series of experiments were carried out in the clean room to study the influence of step characteristic by different turn off methods.The experimental results show that the steplength was 230 nm by method A and 125 nm by method B,while cycles of driving signals were 6.The method B has a smaller steplength when cycles are 6.The average steplength varies in non-linear while driving cycles changing.The steplength varies approximately in linear while voltage amplitude changing.Therefore,method B is better to implement step control,because it gets a better control in positioning system.

关键词： linear ultrasonic motor turned off characteristics step control steplength

Ricci Positive Metrics on the Moment-Angle Manifolds

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Chinese Annals of Mathematics,Series B 2019年第3期40卷 469-480页

作者： Liman CHEN Feifei FAN School of Mathematical Sciences Capital Normal University School of Mathematics Sun Yat-sen University

In this paper, the authors consider the problem of which(generalized) momentangle manifolds admit Ricci positive metrics. For a simple polytope P, the authors can cut off one vertex v of P to get another simple polytope P_v, and prove that if the generalized moment-angle manifold corresponding to P admits a Ricci positive metric, the generalized moment-angle manifold corresponding to P_v also admits a Ricci positive metric. For a special class of polytope called Fano polytopes, the authors prove that the moment-angle manifolds corresponding to Fano polytopes admit Ricci positive metrics. Finally some conjectures on this problem are given.

关键词： Moment-Angle manifolds Simple polytope Cutting off face Positive Ricci curvature Fano polytope

Design of off/ON fluorescent thiol probes based on coumarin fluorophore

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Science China Chemistry 2012年第9期55卷 1776-1780页

作者： SUN Wei LI Jing LI WenHua SU LiJuan DU LuPei LI MinYong Key Laboratory of Chemical Biology of Natural Products(MOE) Department of Medicinal ChemistrySchool of PharmacyShandong UniversityJinan 250012China

This paper presents a series of first-and second-generation click-modified coumarin-based fluorescent probes for thiols.These molecules demonstrate high turn-on fluorescent response and good selectivity towards aromatic thiols over other relevant reactive sulfur species,reactive oxygen species and common nucleophiles.Moreover,probe 1a can detect thiols in the reduced rabbit plasma sample.Therefore,this approach provides a particularly impressive tool for detecting thiol in biological systems.

关键词：荧光探针香豆素类探针设计巯基 off 基础荧光反应亲核试剂

Dynamics Analysis of Carrier-Based Aircraft with off-Center Catapult Launch

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第3期36卷 468-478页

作者： ZHOU Jin ZHU Jianhui TONG Mingbo School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191P.R.China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

In order to enhance the safety of the catapult launch of the carrier-based aircraft,the catapult launch multibody dynamic model is established aiming at the problem of off center catapult launch.The whole catapult process including four stages which are buffering,tensioning,releasing and taxiing is taken into consideration and the body dynamics of the off-center catapult during each stage is analyzed.The catapult launch dynamic differences between the conditions only considering taxiing and that considering four stages are compared,and the effects of the different initial off center distances considering four stages on the attitude,landing gear load and acceleration of the carrier based aircraft during catapult launch are discussed.The results show that only considering taxiing may underestimate the dynamics of the carrier-based aircraft substantially.When taking four stages into consideration,the initial off-center distance has small influence on the aircraft dynamic characteristics during buffering and tensioning but has larger influence on that during releasing and taxiing.The increase of the off-center distance will cause the enhancement of the aircraft rolling and yawing,which may lead to the load difference between the left and right landing gears and the increase of the aircraft lateral acceleration.The establishment and simulation of the catapult launch multi body dynamic model founded on buffering,tensioning,releasing and taxiing provide reference for the carrier-based aircraft design and analysis of the catapult launch dynamics.

关键词： carrier-based aircraft catapult launch off center distance attitude angle landing gear

日本新古书店的成功之道:以BOOK off为中心

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编辑之友 2023年第7期 107-112页

作者：吴琼付国乐安徽财经大学文学院安徽蚌埠233030 南京邮电大学传媒与艺术学院江苏南京210000

当前,建构循环型社会已是全球不二共识,世界各国之各个行业无不为之“上下求索”。日本新古书店BOOK off以文化为连接,围绕循环再利用进行思考、想象与实践,以“书+N”为路径给大众带来二手生活方式提案,在盈利的同时不忘观照现实,与读... 详细信息

当前,建构循环型社会已是全球不二共识,世界各国之各个行业无不为之“上下求索”。日本新古书店BOOK off以文化为连接,围绕循环再利用进行思考、想象与实践,以“书+N”为路径给大众带来二手生活方式提案,在盈利的同时不忘观照现实,与读者共创价值,为公益精神的建构、传播与书写贡献力量。分析与研究BOOK off的成功之道,可为塑造“中国版”的循环再利用理念构建相关的行为逻辑,探索具体的实践方法,提供借鉴与参照。

关键词： BOOK off 循环再利用 SDGs 公益书写

Distribution of chlorophyll-a off the Changjiang River and its dynamic cause interpretation

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Science China Earth Sciences 2005年第7期48卷 950-956页

作者： ZHU Jianrong State Key Laboratory of Estuarine and Coastal Research East China Normal University Shanghai 200062 China

An interdisciplinary comprehensive survey was conducted in August 2000 with the modern measurement instruments off the Changjiang River. The analysis of the observation data shows that there exist two sources of phytoplankton blooms off the Changjiang River. The one with wider spatial extent and stronger intensity appears in the surface plume due to photosyn- thesis produced by the eutrophication brought by a huge amount of nutrient load via the Chang- jiang River and well light penetration because of lower turbidity seawater. Photosynthesis pro- duces chlorophyll-a (Chl-a), meanwhile releases oxygen and absorbs carbon dioxide, so the high Chl-a concentration distribution corresponds to the distribution of high dissolved oxygen and pH. The other with smaller spatial extent and weaker intensity exists in the thermocline in the Taiwan Warm Current (TWC), but the high Chl-a concentration does not correspond to the high dissolved oxygen and pH, which may be a result of long distance advection by the TWC. The eutrophica- tion associated with the huge amount of nutrient flowing into the sea via the Changjiang River is the main cause of the red tide bloom in the area off the Changjiang River, the red tide that oc- curred along the Fujian and Zhejiang coast can influence the area off the Changjiang River pos- sibly via the TWC. The distributions of current simulated by a three-dimension numerical model support the above conclusion.

关键词： area off the Changjiang River field survey red tide eutrophication Taiwan Warm Current.

A Preliminary Analysis of Trace-Elemental Signatures in Statoliths of Different Spawning Cohorts for Dosidicus gigas off EEZ Waters of Chile

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Journal of Ocean University of China 2015年第6期14卷 1059-1067页

作者： LIU Bilin CHEN Xinjun FANG Zhou HU Song SONG Qian College of Marine Sciences Shanghai Ocean University Collaborative Innovation Center for Distant-Water Fisheries The Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of Education National Engineering Research Center for Oceanic Fisheries Shanghai Ocean University Collaborative Innovation Center for National Distant-water Fisheries

We applied solution-based ICP-MS method to quantify the trace-elemental signatures in statoliths of jumbo flying squid, Dosidius gigas, which were collected from the waters off northern and central Chile during the scientific surveys carried out by Chinese squid jigging vessels in 2007 and 2008. The age and spawning date of the squid were back-calculated based on daily increments in statoliths. Eight elemental ratios(Sr/Ca, Ba/Ca, Mg/Ca, Mn/Ca, Na/Ca, Fe/Ca, Cu/Ca and Zn/Ca) were analyzed. It was found that Sr is the second most abundant element next to Ca, followed by Na, Fe, Mg, Zn, Cu, Ba and Mn. There was no significant relationship between element/Ca and sea surface temperature(SST) and sea surface salinity(SSS), although weak negative or positive tendency was found. MANOVA analysis showed that multivariate elemental signatures did not differ among the cohorts spawned in spring, autumn and winter, and no significant difference was found between the northern and central sampling locations. Classification results showed that all individuals of each spawned cohorts were correctly classified. This study demonstrates that the elemental signatures in D. gigas statoliths are potentially a useful tool to improve our understanding of its population structure and habitat environment.

关键词： jumbo flying squid element/Ca off EEZ waters of Chile solution-based ICP-MS environmental variables