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Investigation on the computation of atomic multipole moments with the modified cumulative potential-derived semiempiricalmethod

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Chinese Journal of Chemistry 1997年第6期15卷 481-491页

作者： Xu, LJ Zhu, cb Yan, JM Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

The suitability of calculating atomic multipole moments from AM1 wave functions by cumulative potential-derived method has been investigated. It is shown that this method has a faster convergence of the fitting process and gives a better description of the charge distribution than the original PD method. Atomic charges obtained in this way are of comparable quality with 6-31G* data and the calculated dipole moments are closer to the experimental data than the values computed directly from the AM1 charges. The results demonstrate that the atomic multipole moments higher than monopole moment can be used to supplement the atomic charge to obtain a more accurate description of charge distribution. For the sake of comparison, both the Williams fitting potential surface and the Connolly one are used in the calculation.

关键词： atomic charge atomic multipole moment cumulative fitting AM1

INVESTIGATION　ON　THE　INTERACTION　OF　THE　HALOGEN　ATOMS　WITH　THE　C_（60）　CAGE　IN　THE　HALOGEN－ENCLOSED　COMPLEXES　（HALOGEN＠C_（60））

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Chinese Chemical Letters 1995年第10期6卷 867-870页

作者： Zhu, cb Yan, JM Acad Sinica Inst Chem Beijing 100080 Peoples R China

The interaction between C60 cage and the centerhalogen atoms in endoheoral complexes(HalogenC60)(Halogen=Hal=F,ClBr1),including electro-static interaction,dispersive interection and repulsive interaction,have been calculated by molecular molecular mechanics method combined with the results obtained by quantum-chemical EHMO/ASED method The computational results show that the total interaction is attraction which reduces the endohedral comples system except for,and the electro-static interaction plays a decisive role in the three forms of interactions,reaching up more than 90%. For the endohedral complex the resultant non-bonded interaction is *** is a similar variation trend for the total energy variation of system and the total interaction energy of which the order is (F@C_(60))<(cl@C(60))<(I@C(60)).

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Annealing Effect on Mechanical Properties of Ti_(51)Ni_(13)Pd_(36)High Temperature Memory Alloy

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Journal of Materials Science & Technology 2000年第5期16卷 531-533页

作者： Xu, HB Hu, SQ Jiang, cb Gong, SK Beijing Univ Aeronaut & Astronaut Dept Mat Sci & Engn Beijing 100083 Peoples R China

The high temperature shape memory alloy Ti51Ni13Pd36 was subjected to a cold working and annealing treatment to improve its mechanical properties and the shape memory effect. It was found that recovery of the cold worked alloys started at near 673 K and the recrystallization temperature was at about 748 K. The grain size decreased with the increase of annealing temperature below 923 K and then increased when above 923 K. The smallest average grain size of about 3.5μm, which is approximately 10 times smaller than the hot rolled one, permitted the best combination of the mechanical properties in the alloy annealed at 923 K for 1h. The cold rolling raised the peak temperature of reverse transformation. This temperature dropped very sharply when the specimen was annealed at temperatures higher than 673 K.

关键词： Alloys

Y-Ba-Cu-O mixed oxides for production of diphenols in liquid-solid phase

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Chinese Journal of Chemistry 1996年第6期14卷 516-524页

作者： Liu, cb Zhao, Z Yang, XG Ye, XK Wu, Y CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022JILINPEOPLES R CHINA

Superconductor mixed oxides were often used as catalysts at higher temperature in gas phase oxidations, and considered not suitable for lower temperature reactions in the liquid-solid phase; here the catalysis of YBa2Cu3O7+/-x and Y2BaCuO5+/-x in the phenol hydroxylation at lower temperature with H2O2 as oxygen donor was studied, and found that the superconductor YBa2Cu3O7+/-x, has no catalytic activity for phenol hydroxylation, but Y2BaCuO5+/-x does, even has better catalytic activity and stability than most previously reported ones. With the studies of catalysis of other simple metal oxides and perovskite-like mixed oxides, a radical substitution mechanism is proposed and the experimental facts are explained clearly, and draw a conclusion that the perovskite-like mixed oxides with (AO)(ABO(3)) and (AO)2(ABO(3)) structure have better catalytic activity than the simple perovskite oxides with (ABO(3))(3) structure alone, and (AO) structure unit is the key for the mixed oxides to have the phenol hydroxylation activity. No pollution of this process is very important for its further industrial application.

关键词： superconductor mixed oxides phenol hydroxylation radical substitution

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慢性肾脏病伴高血压患者的强化血压控制

中华高血压杂志(中英文) 2010年第11期18卷 1005-1005页

作者：张玲玉叶鹏 Appel Lawrence J W Jackson TJr G Tom A Lawrence YA brad cb George LC William HC Jeanne C Gabriel F Marquetta LG Francis BG Jennifer JH Lee AJ Kenneth AK Joel DK John WL James PL Janice PL Julia BL Michael SM Shaul GM Edgar RN Keith P Robert AP Velvie AR Otelio SR StephenG S Miroslaw JT Robert DW Xuelei

在观察性研究中发现,血压与终末期肾脏病(endstage renal disease,ESRD)直接相关,并且相互促进。非洲裔美国人中高血压相关的慢性肾脏病和ESRD的患病比例相当高,但极少有试验去检验对非洲裔美国人进行强化血压控制是否能够延缓其慢性肾... 详细信息

在观察性研究中发现,血压与终末期肾脏病(endstage renal disease,ESRD)直接相关,并且相互促进。非洲裔美国人中高血压相关的慢性肾脏病和ESRD的患病比例相当高,但极少有试验去检验对非洲裔美国人进行强化血压控制是否能够延缓其慢性肾脏病进展。方法:入选慢性肾脏病伴高血压的非洲裔美国人患者1094例作为研究对象,随机给予强化或者标准的血压控制治疗。[第一段]

关键词：慢性肾脏病高血压患者血压控制平均血压

The Early-Middle Pleistocene Transition： characterization and proposed guide for the defining boundary

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Episodes 2008年第2期31卷 255-259页

作者： Martin J. Head brad Pillans Sarah A. Farquhar Department of Earth Sciences Brock University St Catharines Ontario L2S 3A1 Canada. Research School of Earth Sciences The Australian National University Canberra ACT 0200 Australia. Cambridge Quaternary Department of Geography University of Cambridge Downing Place Cambridge CB2 3EN United Kingdom.

The mid-Pleistocene transition （MPT, c. 1.2 to 0.5 Ma） records fundamental changes in Earth＇s climate state, where low-amplitude 41-kyr obliquity-dominated cycles gave way progressively to the high-amplitude, quasiperiodic （c. 100-kyr） fluctuations that characterize the later Pleistocene and Holocene. We use wavelet analysis on the LR04 δ^l8O benthic foraminiferal stack to confirm low-frequency power as early as 1.25-1.20 Ma, determine the persistence of obliquity-dominated cyclicity through and beyond the MPT, and reveal new levels of complexity in climate evolution.

关键词：地球气候状态洪积世振幅

The Use of 'In Process' Monitoring Equipment in Heat Treatment Today

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材料热处理学报 2004年第5期25卷 591-596页

作者： Dave Plester Datapaq limited Cambridge CB4 OGU UK

This paper looks at how in-process temperature monitoring systems are being increasingly used in heat treatment applications such as surface hardening, annealing, normalizing, tempering etc. We look at the basic equipment required to successfully monitor from within a furnace and how developments such as RF transmission have enhanced the effectiveness of profiling trials to the point where on line adjustments to furnace conditions can be seen and analyzed in real time. We examine how continuous processes can benefit from this type of monitoring and also how routine operations such as furnace surveying in batch furnaces can benefit greatly from in-process monitoring. Advances in software are also considered, showing how packages are now designed to speed up the processing of data in day to day heat treatment operations.

关键词：热处理温度监测器射频传输剖面测量

Management of hilar cholangiocarcinoma in the North of England: Pathology, treatment, and outcome

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World Journal of Gastroenterology 2005年第48期11卷 7625-7630页

作者： SD Mansfield O Barakat RM Charnley BC Jaques cb O'Suilleabhain PJ Atherton D Manas Department of Hepato-Pancreatico-Biliary Surgery

AIM: To assess the management and outcome of hilar cholangiocarcinoma (Klatskin tumor) in a single tertiary referral ***: The notes of all patients with a diagnosis of hilar cholangiocarcinoma referred to our unit for over an 8-year period were identified and retrospectively reviewed. Presentation, management and outcome were ***: Seventy-five patients were identified. The median age was 64 years (range 34-84 years). Male to female ratio was 1:1. Eighty-nine percent of patients presented with jaundice. Most patients referred were under Bismuth classification 3a, 3b or 4. Seventy patients required biliary drainage, 65 patients required 152percutaneous drainage procedures, and 25 had other complications. Forty-one patients had 51 endoscopic drainage procedures performed (15 failed). Of these,36 subsequently required percutaneous drainage. The median number of drainage procedures for all patients was three, 18 patients underwent resection (24%), nine had major complications and three died *** 5-year survival rate was 4.2% for all patients, 21%for resected patients and 0% for those who did not undergo resection (P = 0.0021). The median number of admissions after diagnosis in resected patients was two and three in non-resected patients (P＜0.05).Twelve patients had external-beam radiotherapy, seven brachytherapy, and eight chemotherapy. There was no significant benefit in terms of survival (P = 0.46) or hospital ***: Resection increases survival but carries the risk of significant morbidity and *** biliary drainage is almost always necessary and endoscopic drainage should be avoided if possible.

关键词： Hilar cholangiocarcinoma Pathology Treatment Outcome England

Cloning of murine BRI3 gene and study on its function for inducing cell death

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Chinese Science Bulletin 2002年第5期47卷 375-378,441页

作者： Lin, LZ Yu, H Ying, MY Tang, J Zhou, W Zhao, SY Li, cb Fudan Univ Sch Life Sci Inst Genet State Key Lab Genet Engn Shanghai 200433 Peoples R China

To understand the molecular mechanism of TNFα effects, the cDNA of murine BRI3 gene was cloned from the total RNA of murine brain endothelial cells (bEnd.3) treated with hTNFa by using the suppression subtractive hybridization (SSH) and the RT-PCR method. The fusion expression vector harbouring BRI3 gene and enhanced green fluorescence protein (EGFP) thus obtained were designated as pEGFP/I3. Then pEGFP/I3 was transiently transfected into L929 cells and the fusion protein EGFP/I3 was localized in cytoplasm. It is found that the expression of EGFP/I3 could induce cell death in L929 cells detected by TUNEL method and flow cytometry. And the overexpression of Bcl-2 in L929 cells can block cell death induced by EGFP/I3, indicating that murine BRI3 gene might related to the TNFα mediated cytotoxicity.

关键词： tumor necrosis factor α BRI3 fusion protein cell death.