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Rare Metals 2011年第5期30卷 544-549页

作者： liang xuebing JIA Chengchang CHU Ke CHEN Hui School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China General Research Institute for Nonferrous Metals （GRINM） Beijing 100083 China

The interfacial thermal conductance （ITC） and thermal conductivity （TC） of diamond/Al composites with various coatings were theoretically studied and discussed. A series of predictions and numerical analyses were performed to investigate the effect of thickness, sound velocity, and other parameters of coating layers on the ITC and TC. It is found that both the ITC and TC decline with increasing coating thickness, especially for the coatings with relatively low thermal conductivity. Nevertheless, if the coating thickness is close to zero, or quite a small value, the ITC and TC are mainly determined by the constants of the coating material. Under this condition, coatings such as Ni, TiC, Mo 2 C, SiC, and Si can significantly improve the ITC and TC of diamond/Al composites. By contrast, coatings like Ag will exert the negative effect. Taking the optimization of interfacial bonding into account, conductive carbides such as TiC or Mo 2 C with low thickness can be the most suitable coatings for diamond/Al composites.

关键词： metallic matrix composites coatings diamonds thermal conductivity interfacial thermal conductance

Effect of particle size on the microstructure and thermal conductivity of Al/diamond composites prepared by spark plasma sintering

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Rare Metals 2009年第6期28卷 646-650页

作者： CHU Ke JIA Chengchang liang xuebing CHEN Hui GAO Wenji School of Material Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Spark plasma sintering （SPS） was used to fabricate Al/diamond composites. The influence of diamond particle size on the microstructure and thermal conductivity （TC） of composites was investigated by combining experimental results with model prediction. The results show that both composites with 40 pan particles and 70 μm particles exhibit high density and good TC, and the composite with 70 μm particles indicates an excellent TC of 325 W.m^-1.K^-1. Their TCs lay between the theoretical estimated bounds. In contrast, the composite with 100 lain particles demonstrates low density as well as poor TC due to its high porosity and weak interfacial bonding. Its TC is even considerably less than the lower bound of the predicted value. Using larger diamond particles can further enhance thermal conductive performance only based on the premise that highly dense composites of strong interfacial bonding can be obtained.

关键词： metal matrix composites thermal properties sintering particle size

Effect of powder mixing process on the microstructure and thermal conductivity of Al/diamond composites fabricated by spark plasma sintering

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Rare Metals 2010年第1期29卷 86-91页

作者： CHU Ke, JIA Chengchang, liang xuebing, and CHEN Hui School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China School of Materials Science and Engineering University of Science and Technology Beijing

Two powder mixing processes, mechanical mixing （MM） and mechanical alloying （MA）, were used to prepare mixed Al/diamond powders, which were subsequently consolidated using spark plasma sintering （SPS） to produce bulk Al/diamond composites. The effects of the powder mixing process on the morphologies of the mixed powders, the microstructure and the thermal conductivity of the composites were investigated. The results show that the powder mixing process can significantly affect the microstructure and the thermal conductivity of the composites. Agglomerations of the particles occurred in mixed powders using MM for 30 min, which led to high pore content and weak interfacial bonding in the composites and resulted in low relative density and low thermal conductivity for the composites. Mixed powders of homogeneous distribution of diamond particles could be obtained using MA for 10 min and MM for 2 h. The composite prepared through MA indicated a high relative density but low thermal conductivity due to its defects, such as damaged particles, Fe impurity, and local interfacial debonding, which were mainly introduced in the MA process. In contrast, the composite made by MM for 2 h demonstrated high relative density and an excellent thermal conductivity of 325 W.m^-1.K^-1, owing to its having few defects and strong inter-facial bonding.

关键词： metal matrix composites thermal properties sintering powder mixing

妊娠期糖尿病孕妇尿路感染的临床特征与危险因素分析

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国际泌尿系统杂志 2024年第5期44卷 887-890页

作者：凌勇赵越梁雪冰陈晓丽叶龙刘洁南方医科大学附属广东省人民医院(广东省医学科学院)检验科广州510080 南方医科大学附属广东省人民医院(广东省医学科学院)生殖医学科广州510080

目的探讨妊娠期糖尿病(GDM)孕妇发生尿路感染的临床特征与相关危险因素。方法选取2017年1月至2021年12月在本院收治的289例确诊为GDM的孕妇,对GDM孕妇发生尿路感染的发病率、病原菌分布以及耐药性进行回顾性分析,并采用logistic回归模... 详细信息

目的探讨妊娠期糖尿病(GDM)孕妇发生尿路感染的临床特征与相关危险因素。方法选取2017年1月至2021年12月在本院收治的289例确诊为GDM的孕妇,对GDM孕妇发生尿路感染的发病率、病原菌分布以及耐药性进行回顾性分析,并采用logistic回归模型分析GDM孕妇发生尿路感染的相关危险因素。结果289例GDM孕妇中有32例发生尿路感染,发病率为11.07%。洁净中段尿培养共检出32株病原菌,其中以大肠埃希菌为主[53.13%(17/32)],其次是无乳链球菌[15.63%(5/32)]。大肠埃希菌对氨苄西林耐药率较高,对阿米卡星、β-内酰胺酶抑制剂合剂、碳青霉烯类等抗菌药物耐药率较低。单因素分析结果显示,三酰甘油(TG)、糖化血红蛋白(HDL-C)、高密度脂蛋白胆固醇(HbA1c)均是GDM孕妇发生尿路感染的危险因素(均P<0.05)。多因素分析结果显示,TG是GDM孕妇发生尿路感染的独立危险因素(OR=1.276,95%CI:1.066~1.526,P<0.05)。结论TG与GDM孕妇尿路感染的发生有关,临床上可采取相应措施,以降低尿路感染的发病率,并根据患者病情合理选择抗菌药物。

关键词：孕妇糖尿病尿路感染

下颌骨外板矢状劈开自体骨充填术矫正半侧颜面短小

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中华整形外科杂志 2024年第3期40卷 249-257页

作者：归来牛峰俞冰刘剑锋陈莹付茜徐史兴乔嘉靳琦贺宇梁雪冰崔蕾陈甫寰陈琪中国医学科学院北京协和医学院整形外科医院颅颌面外科北京100144

目的探讨采用矢状劈开患侧下颌骨外板并植入健侧切取的下颌骨外板修复重建半侧颜面短小的新方法。方法回顾性分析2006年3月至2023年3月,中国医学科学院整形外科医院颅颌面外科收治的半侧颜面短小患者临床资料。术前根据临床表现和影像... 详细信息

目的探讨采用矢状劈开患侧下颌骨外板并植入健侧切取的下颌骨外板修复重建半侧颜面短小的新方法。方法回顾性分析2006年3月至2023年3月,中国医学科学院整形外科医院颅颌面外科收治的半侧颜面短小患者临床资料。术前根据临床表现和影像学检查结果进行诊断和手术设计。所有病例均在全身麻醉下完成手术。经口内入路将患侧下颌骨外板劈开,然后根据术前设计采取健侧适当形态和大小的下颌骨外板植入劈开的骨间隙并采用钛合金小夹板予以坚强内固定。术后随访患者的并发症发生、面部形态改善情况及患者对手术效果满意度,满意度评分为1~5分,分数越高表示越满意。在术前、术后即刻和术后远期(末次)随访时拍摄照片并分析畸形严重程度。将患者术前、术后即刻、术后远期随访CT数据以Dicom格式导入Surgicase Proplan医学三维图像工作站后,利用Segmentation功能重建下颌骨,测量术前、术后即刻和术后远期随访的下颌骨厚度,对其测量值比较采用重复测量方差分析,多重比较采用LSD检验;用多样本Kruskal-Wallis秩和检验对畸形矫正外观满意度评分进行统计分析,以P0.05)。结论下颌骨外板矢状劈开符合下颌骨解剖学特点并为自体骨的植入和愈合提供了良好条件。健侧下颌骨外板的切取,在充填患侧增加厚度的同时,缩小健侧下颌角区厚度,从而有效矫正下颌骨不对称畸形。该方法操作简单,并发症少,效果良好,是矫正半侧颜面短小的理想治疗手段之一。

关键词：下颌骨颜面发育不全下颌骨重建骨移植骨生成下颌骨外板下颌骨外板矢状劈开半侧颜面短小

Effect of processing parameters on the microstructure and thermal conductivity of diamond/Ag composites fabricated by spark plasma sintering

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Rare Metals 2010年第6期29卷 625-629页

作者： GAO Wenjia,JIA Chengchang,JIA Xian,liang xuebing,CHU Ke,ZHANG Luman,HUANG Hai,and LIU Meng School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China School of Materials Science and Engineering University of Science and Technology Beijing Beijing China

Diamond/metal composites with 50 vol.% diamond have been produced by spark plasma sintering（SPS） using pure Ag as a matrix and diamond particles as *** kinds of powder mixing processes were used to prepare the mixture of diamond/Ag powders：dry mixing without milling medium,wet mixing and magnetic ***,they were all consolidated by SPS at various processing parameters to produce bulk diamond/Ag *** samples were heat treated in order to obtain a higher thermal *** effect of processing parameters on the morphologies of the mixed powders,the microstructure and the thermal conductivity of the composites were investigated by comparing the experimental *** reveals that particles were easy to agglomerate and the distribution of mixed powders was inhomogeneous by dry mixing method,and wet mixing method is too *** most favorable mixing process is magnetic blending by which the powders can be homogenously mixed and the composites prepared by optimized SPS processing parameters can obtain the highest relative density and the best thermal conductivity among the composites prepared by different *** magnetic blending diamond/Ag composites even have a 23% increase in thermal conductivity compared with pure silver sintered by SPS.

关键词： metal matrix composites powder mixing spark plasma sintering thermal conductivity

注射成形与压力熔渗方法制备高体积分数SiC_P/Al封装盒体及其导热性能分析

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粉末冶金技术 2007年第5期25卷 348-351页

作者：褚克贾成厂梁雪冰曲选辉北京科技大学材料科学与工程学院北京100083

先用注射成形方法制备出SiC预成形坯,然后使用压力熔渗方法将熔融Al熔渗于预成形坯体得到含65%(体积分数)SiC颗粒的SiCp/Al复合材料的封装盒体。SEM分析结果表明,封装盒体中的Al熔渗完全,内部组织均匀,且基本达到完全致密化;XRD分析结... 详细信息

先用注射成形方法制备出SiC预成形坯,然后使用压力熔渗方法将熔融Al熔渗于预成形坯体得到含65%(体积分数)SiC颗粒的SiCp/Al复合材料的封装盒体。SEM分析结果表明,封装盒体中的Al熔渗完全,内部组织均匀,且基本达到完全致密化;XRD分析结果得出,压力熔渗SiCP/Al复合材料中有微量的Al4C3生成,少量Al4C3有利于促进复合材料的导热性能;对于高体积分数SiCP/Al复合材料,界面热阻对材料热导率的影响不可忽略,使用等效粒径和Hasselman-Johnson模型计算本试验制备的SiCP/Al复合材料的界面热阻约为4.68×10-8m2.W/K。

关键词： SiCP/Al复合材料压力熔渗热导率界面热阻

金刚石盐浴镀覆温度对Al/金刚石复合材料导热性能的影响研究

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粉末冶金技术 2011年第5期29卷 366-371,379页

作者：梁雪冰贾成厂裴广林北京科技大学材料科学与工程学院北京100083 西安航空制动科技有限公司陕西兴平713106

采用盐浴镀对金刚石颗粒进行表面镀Ti,并采用放电等离子烧结制备高导热Al/金刚石复合材料,探讨了镀覆温度对金刚石表面镀Ti层结构、成分以及Al/金刚石烧结体导热性能的影响。结果表明,在较低的温度(700℃)镀覆30min即能够使金刚石表面... 详细信息

采用盐浴镀对金刚石颗粒进行表面镀Ti,并采用放电等离子烧结制备高导热Al/金刚石复合材料,探讨了镀覆温度对金刚石表面镀Ti层结构、成分以及Al/金刚石烧结体导热性能的影响。结果表明,在较低的温度(700℃)镀覆30min即能够使金刚石表面包覆一层较为均匀的镀Ti层,镀层表面光滑平坦。当镀覆温度升高,金刚石不同类型表面呈现不同的镀层形貌。Ti在金刚石(100)面沉积速率要高于(111)面,表明金刚石(100)面比(111)面活性更高。随着金刚石镀Ti温度的提高,Al/金刚石复合材料的热导率逐步下降。相比之下,700℃镀覆温度下所得金刚石表面镀层较薄,而且镀层与金刚石之间结合力较强,SPS烧结过程中金刚石与Al基体能够实现较为紧密的结合,因而复合材料热导率优于其它更高镀覆温度条件下所制备的Al/金刚石复合材料。

关键词：盐浴镀 Al/金刚石复合材料热导率

毛泽东人民监督思想对疫情防控监督工作的价值

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长沙大学学报 2020年第3期34卷 19-23页

作者：梁雪冰广西师范大学马克思主义学院广西桂林541006

毛泽东人民监督思想是中国民主监督理论的第一个重要里程碑。毛泽东始终坚持以人民为中心,发展人民当家作主,充分发挥人民群众对党和国家的监督作用,这集中体现在注重加强人民群众监督意识、重视畅通人民监督渠道及建立人民群众监督机... 详细信息

毛泽东人民监督思想是中国民主监督理论的第一个重要里程碑。毛泽东始终坚持以人民为中心,发展人民当家作主,充分发挥人民群众对党和国家的监督作用,这集中体现在注重加强人民群众监督意识、重视畅通人民监督渠道及建立人民群众监督机制。在当前人民战"疫"中,必须充分认识人民监督对疫情防控工作的现实意义,深刻把握毛泽东人民监督思想的精髓,进一步解决疫情防控监督工作存在的问题,切实做到及时、准确、全面公开疫情信息,开创多元化群众监督模式,严格落实疫情防控监督责任,依法有序参与疫情防控监督工作,以监督和保障疫情防控工作的顺畅、高效开展。

关键词：毛泽东人民监督疫情防控监督工作

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推进新时代马克思主义意识形态创新性发展

柳州职业技术学院学报 2020年第1期20卷 1-5页

作者：梁雪冰广西师范大学广西桂林541006

马克思主义作为占统治地位的意识形态,在新时代中国特色社会主义背景下,更应彰显出其时代的价值,符合社会发展的要求。推进马克思主义意识形态创新性发展成为当前重要的战略性任务。内容的抽象化理论化、传播方式的单一化、建设人才资... 详细信息

马克思主义作为占统治地位的意识形态,在新时代中国特色社会主义背景下,更应彰显出其时代的价值,符合社会发展的要求。推进马克思主义意识形态创新性发展成为当前重要的战略性任务。内容的抽象化理论化、传播方式的单一化、建设人才资源的缺乏对创新发展马克思主义意识形态造成严重的威胁。因此,作为时代的新人,要保持清醒的头脑,积极应对,根植于通俗化、大众化的表达方式;结合现代化、多样化的传播手段以及培养专业化、素质化的建设队伍。

关键词：新时代马克思主义意识形态创新性发展