Cryogenic treatment was used to improve the tribological properties of Ti6Al4V artificial hip joint implants.Cryogenic treatment at-196℃with different holding time were carried out on Ti6Al4V specimens fabricated usi...Cryogenic treatment was used to improve the tribological properties of Ti6Al4V artificial hip joint implants.Cryogenic treatment at-196℃with different holding time were carried out on Ti6Al4V specimens fabricated using electron beam melting(EBM),and their microstructure and tribological properties evolution were systematically analyzed by scanning electron microscopy(SEM),vickers hardness,and wear tests.The experimental results show that the as-fabricated specimen consists of lamellarαphase andβcolumnar crystal.While,the thickness of lamellarαphase decreased after cryogenic treatment.In addition,it can be found that the fineαphase was precipitated and dispersed between the lamellarαphase with the holding time increase.Vickers hardness shows a trend of first increasing and then decreasing.The wear rate of the specimen cryogenic treated for 24 h is the minimum and the average friction coefficient is 0.50,which is reduced by 14.61%compared with the as-fabricated.The wear mechanism of the as-fabricated specimen is severe exfoliation,adhesive,abrasive,and slight fatigue wear.However,the specimen cryogenic treated for 24 h shows slight adhesive and abrasive wear.It can be concluded that it is feasibility of utilizing cryogenic treatment to reduce the wear of EBMed Ti6Al4V.展开更多
ZnO thin films were deposited on graphite substrates by ultrasonic spray pyrolysis method with Zn（CH3COO）2·2H2O aqueous solution as precursor. The crystalline structure, morphology, and optical properties of th...ZnO thin films were deposited on graphite substrates by ultrasonic spray pyrolysis method with Zn（CH3COO）2·2H2O aqueous solution as precursor. The crystalline structure, morphology, and optical properties of the as-grown ZnO films were investigated systematically as a function of deposition temperature and growth time. Near-band edge ultraviolet （UV） emission was observed in room temperature photoluminescence spectra for the optimized samples, yet the usually observed defect related deep level emissions were nearly undetectable, indicating that high optical quality ZnO thin films could be achieved via this ultrasonic spray pyrolysis method. Considering the features of transferable and low thermal resistance of the graphite substrates, the achievement will be of special interest for the development of high-power semiconductor devices with sufficient vower durability.展开更多
The sound of Suzhou Pingtan,an art form which combines storytelling and ballad singing in the Suzhou dialect,swirled around a hall of the International Department of theCommunist Party of China’s Central Committee(ID...The sound of Suzhou Pingtan,an art form which combines storytelling and ballad singing in the Suzhou dialect,swirled around a hall of the International Department of theCommunist Party of China’s Central Committee(IDCPC)in Beijing on August 31.The singing enchanted the audience,including 400 visiting political party leaders and ambassadors of展开更多
目的探讨胃肠道肿瘤术后胃肠功能障碍的危险因素,为胃肠道肿瘤患者术后胃肠功能障碍的预防及干预提供依据。方法系统检索PubMed、Web of Science、Cochrane library、Embase、中国知网、中国生物医学数据库、万方数据库、维普中文期刊...目的探讨胃肠道肿瘤术后胃肠功能障碍的危险因素,为胃肠道肿瘤患者术后胃肠功能障碍的预防及干预提供依据。方法系统检索PubMed、Web of Science、Cochrane library、Embase、中国知网、中国生物医学数据库、万方数据库、维普中文期刊数据库自建库至2022年10月1日的相关文献,由2名研究者独立筛选文献和提取资料并评价纳入研究的偏倚风险后采用Review Manager 5.3软件进行Meta分析。结果共纳入23篇文献,文献质量整体在中等及以上,总样本量为43878。Meta分析结果显示,性别男(OR=1.58,95%CI:1.25~2.01,P=0.002),年龄≥60岁(OR=2.60,95%CI:1.76~2.87,P<0.001),体质指数≥25.3 kg/m^(2)(OR=1.06,95%CI:1.00~1.12,P=0.040),吸烟史(OR=1.89,95%CI:1.31~2.73,P<0.001),慢性阻塞性肺疾病(OR=1.49,95%CI:1.22~1.83,P<0.001),肠造口术(OR=1.47,95%CI:1.26~1.70,P<0.001),腹部手术史(OR=2.90,95%CI:1.67~5.03,P<0.001),手术部位(OR=1.92,95%CI:1.40~2.62,P<0.001),手术方式(OR=1.68,95%CI:1.08~2.62,P=0.020),手术时长(OR=2.65,95%CI:1.92~3.67,P<0.001),腹腔粘连等级(OR=2.52,95%CI:1.90~3.56,P<0.001),术后阿片类用药史(OR=5.35,95%CI:3.29~8.71,P<0.001)、肿瘤TNM分期(OR=2.58,95%CI:1.84~3.62,P<0.001),术后输血(OR=2.92,95%CI:0.88~9.73,P=0.010)是胃肠道肿瘤患者术后胃肠功能障碍的危险因素。结论影响胃肠道患者手术后胃肠功能障碍的因素较多,临床医护人员要及早识别相关危险因素,并在个性化评估的基础上实施针对性的干预措施,以改善患者临床预后。展开更多
The adoption of the new Foreign Investment Law at the Second Session of the 13th National People's Congress (NPC), China's top legislature, on March 15 shows China s determination to open up further for foreig...The adoption of the new Foreign Investment Law at the Second Session of the 13th National People's Congress (NPC), China's top legislature, on March 15 shows China s determination to open up further for foreign businesses and allay foreign investors' concerns, according to experts.展开更多
"There is light at the end of the tunnel,"Jens Hildebrandt,Executive Director of the German Chamber of Commerce in north China,exclaimed as he officially released the report of the German Chamber of Commerce..."There is light at the end of the tunnel,"Jens Hildebrandt,Executive Director of the German Chamber of Commerce in north China,exclaimed as he officially released the report of the German Chamber of Commerce in China's latest Business Confidence Survey 2023/24 in Beijing on January 24.展开更多
基金Funded by the National Natural Science Foundation of China(No.42102345)the Fundamental Research Funds for the Central Universities(No.2023ZKPYJD03)。
文摘Cryogenic treatment was used to improve the tribological properties of Ti6Al4V artificial hip joint implants.Cryogenic treatment at-196℃with different holding time were carried out on Ti6Al4V specimens fabricated using electron beam melting(EBM),and their microstructure and tribological properties evolution were systematically analyzed by scanning electron microscopy(SEM),vickers hardness,and wear tests.The experimental results show that the as-fabricated specimen consists of lamellarαphase andβcolumnar crystal.While,the thickness of lamellarαphase decreased after cryogenic treatment.In addition,it can be found that the fineαphase was precipitated and dispersed between the lamellarαphase with the holding time increase.Vickers hardness shows a trend of first increasing and then decreasing.The wear rate of the specimen cryogenic treated for 24 h is the minimum and the average friction coefficient is 0.50,which is reduced by 14.61%compared with the as-fabricated.The wear mechanism of the as-fabricated specimen is severe exfoliation,adhesive,abrasive,and slight fatigue wear.However,the specimen cryogenic treated for 24 h shows slight adhesive and abrasive wear.It can be concluded that it is feasibility of utilizing cryogenic treatment to reduce the wear of EBMed Ti6Al4V.
基金Funded by the Fundamental Research Funds for the Central Universities(No.DUT12ZD(G)01)the Opening Project of Key Laboratory of Inorganic Coating Materials,Chinese Academy of Sciences(No.KLICM-2012-01)
文摘ZnO thin films were deposited on graphite substrates by ultrasonic spray pyrolysis method with Zn（CH3COO）2·2H2O aqueous solution as precursor. The crystalline structure, morphology, and optical properties of the as-grown ZnO films were investigated systematically as a function of deposition temperature and growth time. Near-band edge ultraviolet （UV） emission was observed in room temperature photoluminescence spectra for the optimized samples, yet the usually observed defect related deep level emissions were nearly undetectable, indicating that high optical quality ZnO thin films could be achieved via this ultrasonic spray pyrolysis method. Considering the features of transferable and low thermal resistance of the graphite substrates, the achievement will be of special interest for the development of high-power semiconductor devices with sufficient vower durability.
文摘The sound of Suzhou Pingtan,an art form which combines storytelling and ballad singing in the Suzhou dialect,swirled around a hall of the International Department of theCommunist Party of China’s Central Committee(IDCPC)in Beijing on August 31.The singing enchanted the audience,including 400 visiting political party leaders and ambassadors of
文摘The adoption of the new Foreign Investment Law at the Second Session of the 13th National People's Congress (NPC), China's top legislature, on March 15 shows China s determination to open up further for foreign businesses and allay foreign investors' concerns, according to experts.
基金山西省科技创新团队(201605D131044-05)山西省应用基础研究项目(201601D202094)+3 种基金山西医科大学大学生创新创业校级项目(20172116)supported by Science and Technology Innovation Team of Shanxi Province(201605D131044-05)Applied to Basic Research of Shanxi Province(201601D202094)University Innovation and Entrepreneurship School-level Project of Shanxi Medical College(20172116)
文摘目的通过分析慢性淋巴细胞白血病(chronic lymphocytic leukemia,CLL)患者的临床、实验室及随访资料探讨外周血单核细胞绝对计数(absolute monocyte count,AMC)对CLL的预后价值。方法对2002年1月至2017年12月收住山西医科大学第二医院的54例慢性淋巴细胞白血病患者的临床特点、实验室检查、治疗效果、预后进行分析,探讨影响CLL的预后因素。结果 54例患者中,男女比例为2∶1,中位年龄为64岁;其中Binet A期8例,B期25例,C期21例;以疾病进展作为终点得到外周血AMC的受试者工作特征(receiver operating characteristics,ROC)曲线,AMC的截点值为0.67×109/L,曲线的最佳灵敏度为0.710,特异度为0.783,曲线下面积(area under the curve,AUC)为0.771(95%CI:0.644~0.899)。以0.67×109/L为界限,分为高AMC组和低AMC组,低AMC组的患者无进展生存期优于高AMC组(P<0.05),但高AMC组与低AMC组之间总生存期差异无统计学意义(P=0.170)。Cox回归结果表明疾病分期为C期(P=0.038)是总生存期的独立影响因素,AMC>0.67×109/L(P=0.004)及疾病分期为C期(P=0.049)是无进展生存期的独立影响因素。结论初诊时较高的AMC与CLL较快的疾病进展有关,可能为CLL的预后判断提供新依据。
文摘"There is light at the end of the tunnel,"Jens Hildebrandt,Executive Director of the German Chamber of Commerce in north China,exclaimed as he officially released the report of the German Chamber of Commerce in China's latest Business Confidence Survey 2023/24 in Beijing on January 24.
