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Photoinduced Charge Transfer in MBB-PPV/C_(60) Composite Film

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Chinese Physics Letters 2000年第11期17卷 829-831页

作者： guo li-jun MA guo-Hong SHAN Fu-Kai MO Yu-jun QIAN Shi-Xiong Department of Physics Fudan UniversityShanghai 200433 Department of Physics Henan UniversityKaifeng 475001

The photoconductive properties of MBB-PPV/C_(60) composite films fabricated by the physical jet deposition(PJD)technique have been studied on the basis of the photoinduced charge transfer *** the photoex-citation,the transverse photoconductivity of the composite films is greatly enhanced by 4 orders of magnitude due to the efficient excitation transfer process from MBB-PPV(as donor)to C_(60)(as acceptor)occurring at the interface,the separation of charges and the existence of in-layer free *** results indicate that the conjugated polymer/fullerene composite films optimized by an appropriate configuration have potential applications in photoelectric devices and photonic fields.

关键词： composite V/C films

A new aryltetrahydronaphthalene lignan from Epimedium brevicornum

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Chinese Chemical Letters 2011年第1期22卷 85-87页

作者： Hai Zhou li guo jun Luo Hong Mei li Xiao Lei li Rong Tao li The college of life Science and Technology Kunming University of Science and Technology Kunming 650224 China

A new aryltetrahydronaphthalene lignan, （＋）-cycloolivil formaldehyde condensate （1）, was isolated from the whole plants of Epimedium brevicornum （Berberidaceae）. Its structure was elucidated on the basis of MS,... 详细信息

关键词： Epimedium brevicornum lignan Cycloolivil formaldehyde condensate

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曲酸对健康影响的危害评估

毒理学杂志 2024年第2期38卷 109-115页

作者：聂燕敏齐丽娟宁钧宇李国君敬海明高珊北京市疾病预防控制中心食物中毒诊断溯源技术北京市重点实验室北京100013 首都医科大学公共卫生学院北京100069

曲酸(Kojic Acid)作为常见的曲霉属和青霉属真菌的代谢产物,存在于传统酿造和发酵食品中,因其具有防腐、保鲜、抗氧化、抗菌、护色和美白等功效,近年来在食品、化妆品和医药等领域广泛应用。本研究参考粮农组织/世界卫生组织食品添加剂... 详细信息

曲酸(Kojic Acid)作为常见的曲霉属和青霉属真菌的代谢产物,存在于传统酿造和发酵食品中,因其具有防腐、保鲜、抗氧化、抗菌、护色和美白等功效,近年来在食品、化妆品和医药等领域广泛应用。本研究参考粮农组织/世界卫生组织食品添加剂联合专家委员会(Joint FAO/WHO Expert Committee on Food Additives,JECFA)关于系统文献检索指南的方法,通过检索数据库以及权威机构网站中与研究相关的文献,获取相关的试验研究及人群流行病学研究等信息,开展曲酸的健康危害评估。

关键词：曲酸危害识别危害特征描述危害评估

An Inverse Method for Equivalent Gray Gas Radiation Characteristic Parameter

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Journal of Iron and Steel Research International 2013年第4期20卷 1-5页

作者： ZHANG Wei-jun YI Zhi liU Xiao-ting li guo-jun CHEN Hai-geng College of Materials and Metallurgy Northeastern University

Compared with non-gray model,equivalent gray model has equal calculation accuracy but much higher computing *** solve the existing problems of the equivalent gray method,sole ternary model was *** the model,coupling solving process of energy balance equations is omitted and the model zone is real ***,the full furnace temperature and heat flow calculations are avoided,which makes it easier to find the relationship between the equivalent gray gas radiation characteristic parameter and the initial *** radiation characteristic parameter was calculated with different temperature combinations,different model zone sizes and different partial pressures of absorbent *** results show the similar variations in the absorption coefficient and emissivity for the equivalent gray model,which both decrease with the increase of the gas temperature and the surface temperature（especially the former one）as well as the model zone size while increase with the increase of the partial pressure of absorbent gas.

关键词： equivalent gray radiation characteristic parameter sole ternary model

大气压固体分析探针结合单四极杆质谱仪快速检测18种合成大麻素

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质谱学报 2024年第2期45卷 292-300页

作者：许中石陈涛江柯成姚伟宣王继业吴元钊王斌杰李国军浙江警察学院浙江杭州310000 杭州市公安局交通警察支队西湖风景名胜区大队浙江杭州310000

本研究建立了一种大气压固体分析探针结合单四极杆质谱仪(ASAP-MS)快速检测18种合成大麻素(SCs)的方法。通过优化ASAP-MS锥孔电压,确定4种优化电压为15、25、35和50 V,以提供化合物全面的质谱信息。在优化条件下对一系列SCs标准溶液进... 详细信息

本研究建立了一种大气压固体分析探针结合单四极杆质谱仪(ASAP-MS)快速检测18种合成大麻素(SCs)的方法。通过优化ASAP-MS锥孔电压,确定4种优化电压为15、25、35和50 V,以提供化合物全面的质谱信息。在优化条件下对一系列SCs标准溶液进行分析,建立了18种SCs的质谱库,并对本方法进行方法学验证,得到18种SCs的检出限为10~20 mg/L。应用该方法对缴获的15批次未知样品进行检测,9批次呈阳性。该方法具有前处理简单、分析速度快、匹配高效精准、定性准确的优势,可用于基层公安禁毒部门的分析检测。

关键词：合成大麻素大气压固体分析探针结合单四极杆质谱(ASAP-MS) 快速检测自建库

Large margin classification for combatingdisguise attacks on spam filters

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第3期13卷 187-195页

作者： Xi-chuan ZHOU Hai-bin SHEN Zhi-yong HUANG guo-jun li College of Communications Engineering Chongqing UniversityChongqing40044China Institute of VLSI Design Zhejiang UniversityHangzhou 310027China Chongqing Communication Institute Chongqing 400032China

This paper addresses the challenge of large margin classification for spare filtering in the presence of an adversary who disguises the spam mails to avoid being detected. In practice, the adversary may strategically add good words indicative of a legitimate message or remove bad words indicative of spam. We assume that the adversary could afford to modify a spam message only to a certain extent, without damaging its utility for the spammer. Under this assumption, we present a large margin approach for classification of spare messages that may be disguised. The proposed classifier is formulated as a second-order cone programming optimization. We performed a group of experiments using the TREC 2006 Spam Corpus. Results showed that the performance of the standard support vector machine （SVM） degrades rapidly when more words are injected or removed by the adversary, while the proposed approach is more stable under the disguise attack.

关键词： Large margin Spam filtering Second-order cone programming (SOCP) Adversarial classification

Efficient Synthesis of Octalone

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Chemical Research in Chinese Universities 2007年第3期23卷 276-279页

作者： ZHANG Chen CHEN Jin-chun ZHENG guo-jun li Yu-lin State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 P. R. China

A highly efficient and convergent approach for the synthesis of octalone 1, the focal intermediate for the synthesis of several sesquiterpenoids, was developed based on the cationic cyclization strategy of the functio... 详细信息

关键词： Octalone (± )-1β,11-Dihydroxy-△^4-eudesmol Cationic cyclization Sesquiterpenoids Total synthesis

Euler Characteristic and Topological Phase Transition of NUT-Kerr-Newman Black Hole

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Communications in Theoretical Physics 2008年第4期49卷 941-944页

作者： YUE Jing-Hua YANG guo-Hong TIAN li-jun ZHU Shu Department of Physics Shanghai University Shanghai 200444 China

From the Gauss-Bonnet-Chern theorem, the Euler characteristic of NUT-Kerr-Newman black hole is calculated to be some discrete numbers from 0 to 2. We find that the Bekenstein-Hawking entropy is the largest entropy in topology by taking into account of the relationship between the entropy and the Euler characteristic. The NUT-Kerr- Newman black hole evolves from the torus-like topological structure to the spherical structure with the changes of mass, angular momentum, electric and NUT charges. In this process, the Euler characteristic and the entropy are changed discontinuously, which give the topological aspect of the first-order phase transition of NUT-Kerr-Newman black hole. The corresponding latent heat of the topological phase transition is also obtained. The estimated latent heat of the black hole evolving from the star just lies in the range of the energy of gamma ray bursts.

关键词： euler characteristic entropy NUT-Kerr-Newman black hole killing vector field

煤制乙二醇DMO合成系统气相组分影响因素研究

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化肥设计 2024年第4期62卷 16-19,50页

作者：李国君陈松领徐恒恒河南龙宇煤化工有限公司河南永城476600

针对煤制乙二醇DMO(Dimethyl oxalate)合成系统影响气相组分稳定的因素进行了分析,并提出相应的措施和调整手段,为煤制乙二醇DMO合成系统操作提供了宝贵经验。

关键词：酯化加氧量尾气影响因素措施