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Study on the bond Covalency and bond Susceptibility in NdCr_1-xM_xO₃ （M=Mn, Fe, Co）

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Chinese Chemical Letters 1998年第11期9卷 0-0,0-0页

作者： Zhi jian WU Qing bo MENG Si Yuan ZHANG (Changchun Institute of Applied Chemistry Chinese Academy of Sciences, Changchun 130022)

bond covalency, bond susceptibility and macroscopic linear susceptibility in NdCr1-xMxO3 (M=Mn, Fe, Co, 0.0≤x ≤1.0) are investigated by complex chemical bond theory. The results indicate the bond covalencies are insensitive to the doping level. With the increasing doping level, the macroscopic linear susceptibilities increase for M=Mn, Fe, decrease for M=*** valence state of Cr can be strongly influenced by the properties of the doping ions.

关键词： bond covalency bond susceptibility complex chemical bond theory NdCr1-xMxO3

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基于小波变换的超声导波管道腐蚀C扫描

化工学报 2013年第12期64卷 4599-4607页

作者：戴波孙雅静唐建北京石油化工学院信息工程学院北京102617 北京化工大学信息科学与技术学院北京100029

常规超声导波回波信号处理是基于A扫描分析,存在易漏检、无法定位缺陷周向位置等不足,选用L(0,2)模态中心频率为48kHz的导波进行管道检测实验,通过对A扫描检测回波与腐蚀缺陷的对比分析,提出了对A扫描检测回波先进行小波变换处理,再进行... 详细信息

常规超声导波回波信号处理是基于A扫描分析,存在易漏检、无法定位缺陷周向位置等不足,选用L(0,2)模态中心频率为48kHz的导波进行管道检测实验,通过对A扫描检测回波与腐蚀缺陷的对比分析,提出了对A扫描检测回波先进行小波变换处理,再进行log线性化处理,最后使用C扫描显示管道腐蚀检测结果的回波信号处理方法。实验表明,所提方法可有效地检测各类管道腐蚀缺陷,并准确地定位缺陷的轴向和周向位置,为导波技术的实际工程应用提供简单有效的方法。

关键词：超声导波管道腐蚀 C扫描

Apoptosis of human pancreatic carcinoma cell-1 cells induced by Yin Chen Hao Decoction

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World Journal of Gastroenterology 2015年第27期21卷 8352-8357页

作者： Hai-bo Zhou Jing-Ming Chen Li-Ming shao Zhi-Gang Chen Department of Gastroenterology the Second Affiliated Hospital of Zhejiang University School of Medicine

AIM: To evaluate human pancreatic carcinoma cell line(PANC-1) cells apoptosis and Bcl-2 and Bax expression induced by Yin Chen Hao Decoction(YCHD).METHODS: The cell growth inhibitory rate was determined by MTT assay. Apoptosis of PANC-1 cells before and after treatment with YCHD was determined by TUNEL staining. Expression of the apoptosisassociated genes, Bcl-2 and Bax, was detected by immunohistochemical staining and reverse ***: YCHD inhibited the growth of PANC-1 cells. Following treatment with YCHD for 24-96 h, the apoptotic rate of PANC-1 cells increased with time. In addition, the positive rate of Bcl-2 protein expression decreased in a time-dependent manner, whereas the positive rate of Bax protein expression increased in a time-dependent manner. Following treatment of with YCHD for 24-96 h, expression of BAX m RNA increased gradually and BCL-2 m RNA reduced gradually with ***: YCHD induces apoptosis of PANC-1 cells mediated in part via up-regulation of BAX and down-regulation of BCL-2.

关键词： Apoptosis Pancreatic carcinoma Yin ChenHao Decoction

维普期刊数据库评论

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采煤机液压系统的研发现状和实际应用

煤炭技术 2013年第8期32卷 35-36页

作者：邵林波昆明市冶金高等专科学校昆明650033

采煤机液压系统主要涉及到牵引液压系统以及调高液压系统两部分内容,笔者在此以6MG200-WC大倾角采煤机液压系统为例,分别对其牵引液压系统以及调高液压系统的设计研发进行全面分析和探讨,并对采煤机液压系统的实际应用情况进行了阐述。

关键词：采煤机牵引液压系统调高液压系统

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数据定价机制现状及发展趋势

北京邮电大学学报 2019年第1期42卷 120-125页

作者：彭慧波周亚建北京邮电大学网络空间安全学院北京100876

探讨了以合理定价为核心的数据交易机制.介绍了国内外知名的数据交易平台;将当前的数据交易定价机制归纳为4种模型:基于博弈论的协议定价模型、基于数据特征的第三方定价模型、基于元组的定价模型和基于查询的定价模型.通过比较各模型... 详细信息

探讨了以合理定价为核心的数据交易机制.介绍了国内外知名的数据交易平台;将当前的数据交易定价机制归纳为4种模型:基于博弈论的协议定价模型、基于数据特征的第三方定价模型、基于元组的定价模型和基于查询的定价模型.通过比较各模型的优缺点,结合数据定价的相关理论,分析了存在的问题,讨论了一种适用于复杂真实交易环境,能准确衡量隐私和正确评估数据价值的方法,为相关研究提供参考.

关键词：数据定价定价机制博弈论隐私度量

Sirolimus-eluting stents for treatment of drug-eluting versus bare-metal stents restenosis： 42-month clinical outcomes from a Chinese single center

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Chinese Medical Journal 2012年第19期125卷 3398-3403页

作者： YAN Rong-qiang CHEN Ji-lin GAO Li-jian YANG Yue-jin LI jian-jun QIAO Shu-bin XU bo YAO Min QIN Xue-wen LIU Hai-bo WU Yong-jian YUAN Jin-qing CHEN Jue YOU Shi-jie DAI Jun GAO Run-lin State Key Laboratory of Cardiovascular Disease Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China

Background Restenosis of bare-metal stents （BMS） and drug-eluting stents （DES） has been increasingly treated with sirolimus-eluting stents （SES）, but the long-term outcomes are unknown. Methods In our study, 388 consecutive patients （144 DES restenosis and 244 BMS restenosis） with 400 lesions （147 DES restenosis and 253 BMS restenosis） treated with SES were included. The rates of target lesion revascularization （TLR） and major adverse cardiac events （MACE） at 42 months were analyzed. Results At the mean follow-up of 42 months, the rates of death （3.5% vs. 3.3%, P=1.000） and myocardial infarction （2.8% vs. 1.2%, P=0.431） in the DES group and BMS group were comparable. Compared with the BMS group, ischemia-driven TLR occurred with a higher frequency in the DES group （18.8% vs.10.7%, P=0.024）. This translated into an increased rate of MACE in the DES group （22.2% vs. 14.0%, P=0.034）. Stent thrombosis occurred with a similar frequency in both groups （2.8% vs. 1.6%, P=0.475）. Multivariate analysis showed that DES restenosis （OR=1.907, 95% Cl 1.108-3.285, P=0.020） and smoking （OR=2.069; 95% Cl 1.188-3.605; P=0.010） were independent predictors of MACE.

关键词： restenosis percutaneous coronary intervention drug-eluting stents

Structures and Vibrational Spectra of C_(2) and LaC^(+)_(2) Clusters

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Chemical Research in Chinese Universities 1998年第2期14卷 71-75页

作者： WU Zhi jian, MENG Qing bo and ZHANG Si yuan ** (Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022)

C 2 and LaC + 2 were studied using Hartree Fock(HF), B3LYP (Becke 3 paremeter Lee Yang Parr) density functional method, second order Mφller Plesset perturbation(MP2) and coupled cluster singles and doubles with non iterative triples(CCSD(T)) methods. The basis set employed was LANL1DZ. Geometries, vibrational frequencies and other quantities were reported. The results showed that for C 2, all the methods performed well for low spin state(singlet), while only HF and B3LYP remained so for high spin state(triplet). For LaC + 2, four isomers were presented and fully optimized. The results suggested that linear isomers with C ∞v and D ∞h symmetries were predicted to be saddle points on the energy surface for all the methods, while for isomers with C 2v and C s symmetries, they were local minima except C 2v at B3LYP level, and were isoenergetic at HF, MP2 and CCSD(T) levels, near isoenergetic at B3LYP level. From the differences between HOMO and LUMO, it is also known that the isomers with C 2v and C s symmetries offer the largest values and therefore correspond to the most stable structure. For La—C bond lengths, B3LYP gives the shortest, the order is B3LYP

关键词： C 2 LaC + 2 Structure Vibrational frequency Computational methods

Numerical Simulation of the Electromagnetic Continuous Casting for Clad Slab

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Journal of Iron and Steel Research International 2012年第S1期19卷 153-157页

作者： YU Ying-shui WANG Tong-min SUN jian-bo JIE Jin-chuan CAO Zhi-qiang LI Ting-ju School of Materials Science and Engineering Dalian University of Technology School of Materials Science and Engineering Jiamusi University

In this paper,a new electromagnetic continuous casting process to prepare clad slab is *** influence of level direct current electromagnetic field on temperature and flow fields of the melt during the fabrication of clad slab were numerically studied by the engineering software ANSYS and *** results indicated that when the magnetic flux density(B)was 0.15 T,the impact velocity and distance of the flow to the narrow face and underside of the dividing plate decreased *** the flow impact to the liquid pool was *** the same time,the high temperature zone of the melt moved away from the narrow face and the dividing plate,and distributed more uniformly. The wider semi-solid area next to the dividing plate was useful for 3003 and 4004 aluminum alloys to bond.

关键词： clad slab electromagnetic continuous casting numerical simulation

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广义平方素数码

电子与信息学报 2008年第3期30卷 652-655页

作者：刘青格邵定蓉李署坚北京航空航天大学电子信息工程学院北京100083

基于有限扩域与有限基域的对应关系,该文将素数码的构造思想延伸到有限扩域,基于有限扩域乘法,以一般二次既约多项式为模,构造出一类周期增大、序列数目增多的跳频序列族——广义平方素数码,该码具有理想汉明自相关特性和最大互相关值为... 详细信息

基于有限扩域与有限基域的对应关系,该文将素数码的构造思想延伸到有限扩域,基于有限扩域乘法,以一般二次既约多项式为模,构造出一类周期增大、序列数目增多的跳频序列族——广义平方素数码,该码具有理想汉明自相关特性和最大互相关值为2的几乎理想的汉明互相关特性。通过分组,得到具有最大互相关值为1的理想汉明互相关特性的跳频序列组。

关键词：素数码跳频序列广义平方素数码有限扩域