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江淮流域梅雨期持续性强降水及其10～30d低频环流特征

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热带气象学报 2014年第5期30卷 851-860页

作者：王黎娟庞玥于波李业进南京信息工程大学气象灾害预报预警与评估协同创新中心/气象灾害教育部重点实验室江苏南京210044 重庆市气象台重庆401147 安徽省气象局安徽合肥230061

利用1961-2010年中国556站的逐日降水资料和NCEP/NCAR逐日再分析资料,采用合成分析等方法探讨了江淮流域梅雨期持续性强降水的低频振荡特征及其发生前后低频大气环流场的演变特征.结果表明,汀淮梅雨持续性强降水存在显著的10～ 30 d低... 详细信息

利用1961-2010年中国556站的逐日降水资料和NCEP/NCAR逐日再分析资料,采用合成分析等方法探讨了江淮流域梅雨期持续性强降水的低频振荡特征及其发生前后低频大气环流场的演变特征.结果表明,汀淮梅雨持续性强降水存在显著的10～ 30 d低频振荡特征.持续性强降水发生时,汀淮流域对流层高层受东海低频反气旋西北部的偏西气流控制,使得南亚高压位置偏东,加强了高层的辐散型流场;对流层中层,中高纬度地区存在“＋、-、＋”的低频位势高度中心,蒙古低频低压使得极地冷空气易于南侵;对流层低层,汀淮流域受低频P-J波列西段的台湾岛低频反气旋影响,并伴随强烈的对流活动,此反气旋使得西太平洋副热带高压向更西的位置伸展;因此低层辐合、高层辐散使得汀淮流域表现为强烈的低频上升运动,同时低频水汽从孟加拉湾-南海一带输送到汀淮流域,为持续性强降水的发生提供了有利的低频环流条件.另外,在持续性强降水发生前后,低层低频正涡度向北、向西传播,高层低频负涡度向南、向东传播,高低层斜压结构明显,共同作用于汀淮流域,维持持续性强降水过程.

关键词：江淮流域持续性强降水 10 ~ 30 d振荡低频大气环流特征

Interface-modulated approach toward multilevel metal oxide nanotubes for lithium-ion batteries and oxygen reduction reaction

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Nano Research 2016年第8期9卷 2445-2457页

作者： Jiashen Meng Chaojiang Niu Xiong Liu Ziang Liu Hongliang Chen Xuanpeng Wang Jiantao Li Wei Chen Xuefeng Guo Liqiang Mai State Key Laboratory of Advcrnced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China Center for Nanochemistry Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Metal oxide hollow structures with multilevel interiors are of great interest for potential applications such as catalysis, chemical sensing, drug delivery, and energy storage. However, the controlled synthesis of multilevel nanotubes remains a great challenge. Here we develop a facile interface-modulated approach toward the synthesis of complex metal oxide multilevel nanotubes with tunable interior structures through electrospinning followed by controlled heat treatment. This versatile strategy can be effectively applied to fabricate wire-in-tube and tube- in-tube nanotubes of various metal oxides. These multilevel nanotubes possess a large specific surface area, fast mass transport, good strain accommodation, and high packing density, which are advantageous for lithium-ion batteries （LIBs） and the oxygen reduction reaction （ORR）. Specifically, shrinkable CoMn204 tube-in-tube nanotubes as a lithium-ion battery anode deliver a high discharge capacity of -565 mAh-g-1 at a high rate of 2 A.g-~, maintaining 89% of the latter after 500 cycles. Further, as an oxygen reduction reaction catalyst, these nanotubes also exhibit excellent stability with about 92% current retention after 30,000 s, which is higher than that of commercial Pt/C （81%）. Therefore, this feasible method may push the rapid development of one-dimensional （1D） nanomaterials. These multifunctional nanotubes have great potential in many frontier fields.

关键词： interface-modulatedapproach multilevel nanotubes metal oxide lithium-ion battery (LIB~ ~ oxygen reduction reaction(ORR)

The use of fire at Zhoukoudian:evidence from magnetic susceptibility and color measurements

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Chinese Science Bulletin 2014年第8期59卷 1013-1020页

作者： Yan Zhang Zhengtang Guo Chenglong Deng Shuangquan Zhang Haibin Wu Chunxia Zhang Junyi Ge Deai Zhao Qin Li Yang Song Rixiang Zhu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleoanthropology Chinese Academy of Sciences Faculty of Earth Sciences China University of Geosciences

In order to provide direct evidence for the use of fire by humans at Locality 1,Zhoukoudian,we examine the burnt and unburnt sediments of newly excavated area in Layer 4 by detailed measurements of magnetic susceptibility,color,and diffuse reflectance *** show that the magnetic susceptibility and redness of the burnt sediments are remarkably higher than those of other areas on the same level:up to*22 times for magnetic susceptibility and*3 times for redness of those of the adjacent unburnt ***-grained(superparamagnetic/stable single-domain)magnetite and hematite grains make dominant contributions to the distinctly high values of magnetic susceptibility and redness in the burnt *** reflectance spectroscopy results show that the burnt sediments contain more hematite than those of other areas and localities 2 and ***-temperature magnetic susceptibility measurements demonstrate that the burnt sediments have been heated above 700°*** changes in low-frequency magnetic susceptibility and redness are impossibly resulted from natural fires,thus most likely signaling the human activities of controlled use of ***,further work is needed to confirm whether or not these heat-affected sediments were produced in situ.

关键词： Zhoukoudian Use of fire Magneticsusceptibility Redness ~ Rock magnetism

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碳团簇型材料/环氧树脂复合材料吸波性能研究(英文)

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功能材料 2005年第7期36卷 1131-1134页

作者：徐国亮朱正和蒋刚李步云刘波四川大学原子与分子物理研究所四川成都610065

主要研究了碳团簇型材料吸收剂含量,颗粒形状对碳团簇/环氧树脂复合材料吸波性能的影响,并由此制得了在8.2～12.4GHz波段最大反射衰减为-27dB,反射率＜-10dB的有效带宽为全波段的较高性能的复合吸波材料.材料总厚度为2mm,密度为1.16g/c... 详细信息

主要研究了碳团簇型材料吸收剂含量,颗粒形状对碳团簇/环氧树脂复合材料吸波性能的影响,并由此制得了在8.2～12.4GHz波段最大反射衰减为-27dB,反射率＜-10dB的有效带宽为全波段的较高性能的复合吸波材料.材料总厚度为2mm,密度为1.16g/cm3.并采用电磁波理论对材料的吸波性能进行了探讨.

关键词： absorbing material carbon cluster-like material 8.2 ~ 12.4GHz

Effects of Volume Ratios of Water Phase to Oily Phase on Morphology and Releasing Performance of Emulsion Electrospun Fibers

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Journal of Donghua University(English Edition) 2014年第5期31卷 577-581页

作者： LIN Gang HU Jue DING Xin PENG Xiao HU Ji-yong YANG Xu-dong Key Laboratory of Textile Science & Technology Ministry of Education of China Donghua University Shanghai 201620 China College of Textiles Donghua University Shanghai 201620 China

Emulsion electrospinning as a novel process in spinning core-sheath fibers shows a promising potential in drug release control. The volume ratio of water phase to oily phase is one of the critical parameters in forming core-sheath fibers. In this study, water phase was presented by hydrophilic tetracycline hydrochloride and oily phase by hydrophobic poly （E-caprolactone）（PCL）. The effects of volume ratios of water phase to oily phase on fiber morphology and in vitro drug release were investigated. Scanning electron microscopy （ SEM ）, transmission electron microscopy （ TEM）, and eonfoeal laser scanning microscopy（CLSM） were used to observe the morphology, *** structure of the fibers and drug loading in the fibers, respectively. Samples of three different volume ratios of water phase to oily phase, 1： 25, 1：15, and 1：10, were prepared with the same concentration of drug solution. Experiment results showed that, with an increase in the volume ratios of water phase to oily phase, the fiber diameter increased and diameter distribution scattered. The drug entrapment efficiency of the fibers reduces with the increase in volume ratios, L e. , from 73.48 % in the ratio of 1 ： 25, 62.23 % in 1 ： 15, down to 45.63 % in 1：10. In vitro release tests showed that a higher volume ratio of water phase to oily phase would lead to a lower release rate resulted from thicker fiber sheath.

关键词： emulsion electrospinning volume ratio of water phase tooily phase drug entrapment efficiency ~ sustained release

基于Internet的房地产投资决策分析系统

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计算机工程与应用 2003年第35期39卷 189-191,224页

作者：游艳琴王训国丁永生邵世煌东华大学信息科学与技术学院长宁区土地规划管理局上海200336

针对我国房地产开发活动的特点,为房地产投资者开发了一个投资决策分析系统。系统采用C/S与B/S模式相结合的总体架构。详细讨论了该系统的功能设计,探讨了系统实施过程中模型库的设计、工作流过程模型的设计及系统的安全性等关键技术。

关键词：智能决策支持系统(IDSS) 投资分析房地产工作流 1』VV’ o''''1 ,^,㈣1f …… ……… …….一 ~

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耐高低温耐压橡胶弹性材料

宇航材料工艺 2014年第3期44卷 42-45页

作者：余惠琴刘晓红张金明景宽陈雯西安航天复合材料研究所西安710025

采用丁异戊橡胶作为主体材料,从补强体系、硫化体系和增塑剂三个方面分析了它们对橡胶高低温性能、耐老化性能和耐压性能的影响.粒径小、结构度高的炭黑和气相白炭黑并用可有效改善橡胶的力学性能;硫磺含量在0.8％～1.3％使得硫化橡胶... 详细信息

采用丁异戊橡胶作为主体材料,从补强体系、硫化体系和增塑剂三个方面分析了它们对橡胶高低温性能、耐老化性能和耐压性能的影响.粒径小、结构度高的炭黑和气相白炭黑并用可有效改善橡胶的力学性能;硫磺含量在0.8％～1.3％使得硫化橡胶既具备较好的高低温性能又兼顾较好的耐老化性能;增塑剂可有效调整橡胶硬度和耐压性能.并对研制的丁异戊橡胶弹性材料及其柔性接头构件耐高低温性能及耐压性能进行分析.结果表明,弹性材料高低温剪切性能及耐压性能表征结果能初步反映柔性接头构件的摆动性能及耐压性能.

关键词：丁异戊橡胶补强剂硫化体系 -40 ~ +60℃ 压缩

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任意频点双混频时差测量方法及仪器的研究

电子测量与仪器学报 2014年第5期28卷 500-506页

作者：白力军张冠宇苏志强杜向伟河北省计量监督检测院石家庄050051 石家庄数英仪器有限公司石家庄050051

介绍了采用双混频时差法研制的任意频点比对测量系统,媒介频标采用DDS代替了传统的调偏振荡器,采用双混频时差法原理,研发一种1~30 MHz频率范围内任意频点的时差、频差比对分析系统。系统比对测量频率1~30MHz,采样时间100 ms^106s;本底... 详细信息

介绍了采用双混频时差法研制的任意频点比对测量系统,媒介频标采用DDS代替了传统的调偏振荡器,采用双混频时差法原理,研发一种1~30 MHz频率范围内任意频点的时差、频差比对分析系统。系统比对测量频率1~30MHz,采样时间100 ms^106s;本底噪声(1 s)为5MHz/10MHz优于5×10-13,其他频点优于1×10-12。测量系统通过软件算法可以测量稳定度、准确度、相位差、老化率。

关键词：双混频时差法双混频时差频差比对分析系统 1 ~ 30 MHz任意频点比对

EVALUATION OF EFFICACY OF RECOMBINANT-IFN IN TREATMENT OF CHRONIC HEPATITIS C

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Medical Bulletin of Shanghai Jiaotong University 1994年第1期17卷 45-50页

作者：金根娣矢野佑人

Twenty-nine patients with civic hepatitis C (CHC) have been treated witha-IFN (6 MU/d) for eight weeks The sera were collected at six different periods duringthe medical survey, ***-treatment, end of treatment, three months, six months, oneyear, two years after the *** HCV-RNA, as a mark of viral reproduction,was detected ac the trend of ALT was also observed. The results showed that 12 con(41.4%) had continuous responses with negative reverses of HCV-RNA for mere thantwo years. Simultaneously, the levels of ALT for these pothots were also continuously normal9 cases(31.0%) had temporary responses and 8 cases (27.6%)no *** stop re-vealed that the patients with high titre HCV-RNA sera wiht he more sensitive to thetreatrel of a-IFN.

关键词： chronic hepatitis C α-interferonreverse transcription ~ cab reaction