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Formation of Heterocyclic C_(60) Derivative by Gas-Phase Ion/molecule Reaction

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Chinese Chemical Letters 1997年第5期8卷 375-376页

作者： Hao, CY Liu, ZY Guo, XH Liu, sy CHINESE ACAD SCI CHANGCHUN INST APPL CHEMCHANGCHUN 130022PEOPLES R CHINA

Ion/molecule reaedons of C60 with vinyl acetate under chendcal ionization conditions havebeen studied here. Compared with C2H3O~ from acetone. C2H3O~ from vinyl acetate undergoes thereaedons more easily a new heterocycle between C60, and the studied ion is formed. The generation of two0-bonds and little angle tensile force of pentatomic ring make it more stable.

关键词： C-70

Specific Mass Spectrometric Fragmentations from the Dissociation of Intermediate Ion-Neutral Complexes

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Chinese Chemical Letters 1998年第1期9卷 93-97页

作者： She, YM Wei, JH Tu, YP Liu, sy Hunan Normal Univ Anal & Testing Ctr Changsha 410006 Hunan Peoples R China Chinese Acad Sci Changchun Inst Appl Chem Changchun 1300222 Jilin Peoples R China

It is reported that two kinds of specific mass spectrometric fragmentations are generated from dissociations of the intermediates of both the ion-neutral complex and the proton-bound complex. Collision-induced dissociation, isotopic labelling, and semi-empirical AM1 calculations were used to investigate the formation mechanism of the ion of m/z 139 from ionized tetrahydroimidazole-substituted methylene beta-diketones and the unimolecular fragmentations pathway of 3-phenyl-1-butyn-3-ol upon electron impact.

关键词： mass spectrometric fragmentation ion-neutral complex proton bound complex dissociation

Microstructure and Mechanical Property of in-situ Al-Cu/TiC Composites

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Journal of Materials Science & technology 1998年第3期14卷 255-258页

作者： Zhang, EL Zeng, sy Yang, B Li, QC Ma, MZ Harbin Inst technol Sch Mat Sci & Engn Harbin 150001 Peoples R China Jiamusi Univ Jiamusi 154002 Peoples R China

An approach named direct reaction synthesis (DRS) has been developed to fabricate particulate composites with an extremely fine reinforcement size. ID situ Al matrix composites were fabri-cated by DRS. Extensive analysis of the composites microstructure using SEM and teM identify that the reinforcement formed during the DRS process is Ti carbide (TiC) particle, generally less than 1.0 μm. The reacted, semisolid extruded samples exhibit a homogeneous distribution of fine TiC particles in Al-Cu matrix, Mechanical property evaluation of the composites has revealed a very high tensile strength relative to the matrix alloy. Fractographic analysis indicates ductile failure although the ductility and strength are limited by the presence of coarse titanium aluminides (Al3Ti).

关键词： TiC Cu Figure Microstructure and Mechanical Property of in-situ Al-Cu/TiC Composites Al

Production, extraction and characterization of dilutetium fullerenes

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Chinese Science Bulletin 1997年第11期42卷 900-903页

作者： Hao, CY Guo, XH Liu, ZY Liu, sy Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China

THE study on metallofullerenes which gives rise to novel molecules and materials has alwaysbeen one of the most attractive directions of fullerenes research since the discovery of LaC82.But it did not develop rapidly until K-H method was used to prepare metallofullerenes *** most lanthanides including La,Ce,Nd,Sm,Eu,Gd,Tb,Dy,Ho and Er can

关键词： dilutetium fullerenes Lu2C2n high-pressure extraction DEI-MS LDI-MS.

Acute Coronary syndromes in Semi-Urban African Areas: Clinical Aspects and Management in Ziguinchor (Senegal)

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Open Journal of Emergency Medicine 2021年第4期9卷 179-187页

作者： Simon Joël Manga Mame Diarra Mbaye Sidy Lamine sy Quinta te Indafa Cardiology Departement Hospital de la Paix Assane Seck University of Ziguinchor Ziguinchor Senegal Cardiologie Departement Fann National University Center Dakar Cheikh Anta Diop University Ziguinchor Senegal

Context and Objectives: Acute coronary syndromes (ACS) constitute a major medical emergency. In Senegal, outside the capital Dakar, there is a lack of appropriate care structures. The objective of this work was to study the ACS treatment in the city of Ziguinchor. Methodology: This was a retrospective study of acute coronary syndromes’ cases admitted to the two-level two hospitals in the city of Ziguinchor from January 1, 2016 to December 31, 2019. We included all patients with acute angina pain at rest and/or electrocardiographic changes in at least two contiguous leads. The data were analysed using sphinx V5 software. Results: 57 cases were collected. The average age was 60.1 ± 14.1 years. There was a male predominance with a sex ratio of 3.7. The majority of patients arrived at the hospital by unsafe delivery (70.5%). Symptomatology was dominated by typical angina pain (50.8%). On the electrocardiogram, a majority of acute coronary syndromes with ST segment shift were observed (70.2%). Doppler echocardiography found abnormalities in segmental kinetics in 69.8% of cases. The troponin dosage was performed in 7 patients, i.e. 12.3%. The average time of treatment was 3.4 ± 4.5 days. Medical treatment remained standard and no patient was thrombosed. The average hospitalization period was 5 ± 3.2 days. The hospital lethality was 7.2%. Conclusion: Acute coronary syndromes constitute a medical emergency. Dia

关键词： Acute Coronary syndromes Clinic Management Ziguinchor

A Comparison of Rural Development Between China and Vietnam After the Reform

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A Comparison of Rural Development Between China and Vietnam ...

作者： Vo sy 西北农林科技大学

学位级别：硕士

随着济改革地推行,越南和中国在农村地区的发展方面都取得了很大进展。农村居民的生活水平、基础设施、农村经济、产能和社会服务等都因改革而得到显著提升。然而,由于地理条件、气候、人口、经济规模、政府政策、改革程度、资源禀赋和... 详细信息

随着济改革地推行,越南和中国在农村地区的发展方面都取得了很大进展。农村居民的生活水平、基础设施、农村经济、产能和社会服务等都因改革而得到显著提升。然而,由于地理条件、气候、人口、经济规模、政府政策、改革程度、资源禀赋和投资倾向的不同,两国农村发展状况也有所不同。本研究的目的是通过比较改革后中国与越南农村的发展,找到两国农村地区存在的共同问题。此外,通过比较可以得出,在一些方面中国农村比越南发展的更好,而在另外一些方面,越南比中国农村做的好。最后,笔者将为两国农村的发展提出一些适当的建议。通过阅读相关文献和从《家庭生活水平调查》(1993-2012)、《中国农村统计年鉴》(1978-2012)和世界银行(1986-2012)获取的数据,笔者构建了一个指标体系。该指标体系主要用以评估和比较两国实行改革开放政策后,在农村经济、产能、就业、资源禀赋和社会服务等方面的发展水平。笔者使用Excel计算了两国从改革到现在各项指标的均值,用层次分析法(AHP)确定了各个指标在总体中的权重并用密切值法估计了两国最优点集中的密切值。结果显示中国农村发展有着更高的权重,其密切值也更加接近最优集。最后,作者提出以下措施来改善两国农村的发展：(1)在越南,国家必须确定支柱产业、龙头产业;政府应鼓励人民和企业投资于机器、设备和技术;将科技成果应用到生产过程中;加强管理;用政策吸引劳动力到地方工作等。(2)在中国,应鼓励自主就业;优化农村资源配置,促进城乡协调发展,治理农村环境污染,以及发挥工业和城市对农村的资金支持和技术支持,推进农村民主化进程等。本文研究结果表明：(1)在农村经济、产能、就业、资源禀赋和社会服务方面中国做的比越南好;另一方面,在乡村环境、社会公正和福利方面越南比中国做的好。(2)中国的问题有：城市和农村之间的收入差距不断扩大;农村基础设施建设落后于城市;西部和东部农村经济发展不平衡;环境污染严重;乡镇企业在吸收农民工就业方面作用有限;农村地区昂贵的医疗保健系统制约了穷人;全球竞争、自然灾害已经严重影响了人们的生存条件;农民的权利得不到保护等。(3)越南的问题有：农业用地正在萎缩;农业劳动力存在剩余;人均耕地面积较少;农村工业发展缓慢;农村家庭资本积累缓慢;劳动生产率低;农产品价格不稳定;科学技术在农业生产中的运用缓慢。

关键词：农村发展水平层次分析法(AHP) 密切值法中国越南

Bilharzia Appendicitis: Incidence in a Commune in Mali, about 3CAS

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Surgical Science 2024年第5期15卷 321-329页

作者： Souleymane Bingue Dembélé Yely Dianessy Moussa Samake Abdou Guiré Siaka Konaté Ousmane sy Boubacar Yoro Sidibé Amadou Maïga Thiorno Nadio Boubacar Karembe Amaguiré Saye Sirama Diarra Dorcas Sodjiné Yede Issiaka Diarra Ibrahima Maiga Mahamane Dicko Moussa Konaté Aliou Bina Diarra Bakary Tientigui Dembélé General Surgery Department of the District Hospital of Commune IV of Bamako Bamako Mali Kolondié ba Reference Health Centre Sikasso Mali Epidemiology and Clinical Research Bamako Mali General Surgery Department of Gabriel Touré University Hospital Bamako Mali Ophthalmology Department of the District Hospital of Commune IV of Bamako Bamako Mali Gynecology and Obstetrics Department of the District Hospital of Commune IV of Bamako Bamako Mali Commune I of the District of Bamako Reference Health Centre Bamako Mali Imaging Department of the District Hospital of Commune IV of Bamako Bamako Mali Commune VI of the District of Bamako Reference Health Centre Bamako Mali Anotomy-Pathology Department of the G Point University Hospital Bamako Mali

Appendicitis bilharzia is a very rare condition and we report 3 cases of this pathology that sense clinical and biological similarities with bacterial appendicitis. The etiological diagnosis was exclusively histopathological, this allowed to highlight eggs of Schistosome in the appendicular wall in the three patients. The surgical treatment was supplemented by a specific medical treatment based on praziquantel. The surgical suites were simple for 2 patients, complicated by superficial parietal suppuration in a patient.

关键词： Bilharzial Appendicitis Endemic Histopathology Specific Antiparasitic Treatment

Studies of the dissociation and the protonation of TB-chlorosulphophenol

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Chinese Journal of Chemistry 1997年第1期15卷 68-75页

作者： Zhu, CZ Yang, BL Zhao, H Gu, WX Ai, sy Department of Chemistry East China Normal University Shanghai 200062 China [*]Department of Chemistry East China Normal University Shanghai 200062 China

The dissociation constant of each step for TB-chlorosulphophenol has been determined by potentiometric method, and the thermodynamic constants, Delta G degrees, Delta H degrees and Delta S degrees, of the dissociation process have been calculated. The protonation constants were measured by the spectrophotometric method. The pH values of various forms of anions of the chromogenic reagent at their concentrations were also calculated.

关键词： dissociation protonation TB-chlorosulphophenol

Enhancing Precision in Radiotherapy Delivery: Validating Monte Carlo Simulation Models for 6 MV Elekta synergy Agility LINAC Photon Beam Using Two Models of the GAMOS Code

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