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MECHANICAL PROPERTIES AND INTERFACIAL STRUCTURES OF ALUMINIUM BORATE WHISKER REINFORCED ALUMINIUM COMPOSITES

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Acta Metallurgica Sinica(English Letters) 1993年第12期6卷 465-471页

作者： PAN Jin ning xiaoguang HU Kuiyi YE Hengqiang Changsha Institute of Technology ChangshaChina Laboratory of Atomic Imaging of Solids Institute of Metal ResearchAcademia SinicaShenyangChina

Quality 9Al_2O_3-2B_2O_3 whisker reinforced 6061Al or Al composites have been prepared by technique of squeeze casting.The mechanical properties of the 9Al_2O_3·2B_2O_3(w)/6061Al composites could be hardly improved by T6 treatment,owing to cause the remarkable interracial reaction.An observation under high resolution trans- mission electron microscope on interfaces shows that the serious chemical reaction occurs and the product is Al_2MgO_4.But no such reaction is found at the interfaces of 9Al_2O_3. 2B_2O_3(w)/Al composite.EDS analysis on the interfaces shows that above mentioned interracial reaction may be resulted from the interracial segregation of Mg atoms in 6061Al matrix during sequeeze casting.

关键词： aluminium borate whisker Al matrix composite strength interracial structure

Increased Oxygen Vacancies in CuO-ZnO Snowflake-like Composites Drive the Hydrogenation of CO_(2) to Methanol

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 22-33页

作者： San xiaoguang Wu Wanmeng Zhang Lei Meng Dan Chang Xiangshuang Tan Jianen Qi Jian College of Chemical Engineering Shenyang University of Chemical TechnologyShenyang 110142China Shenyang Xinghua Aviation Electrical Appliances Co. Ltd.Shenyang 110023China Department of Prosthodontics PLA 964 HospitalChangchun 130000China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Cu/ZnO is widely used in the hydrogenation of carbon dioxide (CO_(2)) to methanol (CH_(3)OH) to improve the lowconversion rate and selectivity generally observed. In this work, a series of In, Zr, Co, and Ni-doped CuO-ZnO catalysts wassynthesized via a hydrothermal method. By introducing a second metal element, the activity and dispersion of the activesites can be adjusted and the synergy between the metal and the carrier can be enhanced, forming an abundance of oxygenvacancies. Oxygen vacancies not only adsorb CO_(2) but also activate the intermediates in methanol synthesis, playing a keyrole in the entire reaction. Co3O4-CuO-ZnO had the best catalytic performance (a CO_(2) conversion rate of 9.17%;a CH_(3)OHselectivity of 92.77%). This study describes a typical strategy for multi-component doping to construct a catalyst with anabundance of oxygen vacancies, allowing more effective catalysis to synthesize CH_(3)OH from CO_(2).

关键词： CuO-ZnO catalyst CO_(2)hydrogenation to CH_(3)OH doping oxygen vacancy synergy

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我国家庭养老床位的研究现状

南京医科大学学报（社会科学版） 2024年第1期24卷 49-53页

作者：马宁鲁翔黄晓光南京医科大学医政学院江苏南京211166 南京医科大学附属逸夫医院老年医学科江苏南京211112

家庭养老床位为居家养老的老年人提供医、养、护相结合,各类资源整合的一体化居家养老服务,在缓解家庭照护压力、提高家庭照护专业化、减轻家庭养老经济负担等方面具有优势,但仍存在标准化建设不充分、医护资源整合不足、产品和平台待... 详细信息

家庭养老床位为居家养老的老年人提供医、养、护相结合,各类资源整合的一体化居家养老服务,在缓解家庭照护压力、提高家庭照护专业化、减轻家庭养老经济负担等方面具有优势,但仍存在标准化建设不充分、医护资源整合不足、产品和平台待优化、补贴渠道未打通等问题。文章根据学术研究及各地实践现状进行简要梳理并提出对策,以促进我国卫生健康事业高质量发展。

关键词：居家养老家庭养老床位家庭照护医养护一体化

产教融合模式下工程估价课程思政教学改革探索与实践

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河北环境工程学院学报 2024年第1期34卷 89-94页

作者：赵晓光刘芳王丽芸张宁史晓光河北环境工程学院河北秦皇岛066102

在产教协同育人中融入思政教育是应用型本科院校思政育人的必然要求。本研究立足应用型本科院校,以工程估价课程为例,在产教融合模式下探索课程思政改革路径,通过合理设置课程思政目标,深入挖掘课程思政元素,在授课模式、课程考核、实... 详细信息

在产教协同育人中融入思政教育是应用型本科院校思政育人的必然要求。本研究立足应用型本科院校,以工程估价课程为例,在产教融合模式下探索课程思政改革路径,通过合理设置课程思政目标,深入挖掘课程思政元素,在授课模式、课程考核、实训教学以及第二课堂中进行改革与实践,并着力提升校企双师团队的思政素养,同时依托产业学院建设课程思政案例库,构建了融合与创新的工程估价课程思政育人模式,产教协同与思政双驱动育人取得了显著成效。

关键词：产教融合应用型本科院校工程估价课程思政

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重组大肠杆菌全细胞催化制备假尿苷

生物工程学报 2024年第3期40卷 799-811页

作者：王倩倩刘亚琦屈琰刘欢高歌徐庆阳陈宁范晓光天津科技大学生物工程学院天津300457 天津科技大学工业发酵微生物教育部重点实验室天津300457

假尿苷是非编码RNA中含量最多的修饰核苷,在生物和医药领域用途广泛。现有的假尿苷制备方法普遍存在步骤繁琐、生产效率低、生产成本高等缺点。本研究在大肠杆菌中设计了新颖的酶级联反应路线,并实现了全细胞催化尿苷制备假尿苷。首先,... 详细信息

假尿苷是非编码RNA中含量最多的修饰核苷,在生物和医药领域用途广泛。现有的假尿苷制备方法普遍存在步骤繁琐、生产效率低、生产成本高等缺点。本研究在大肠杆菌中设计了新颖的酶级联反应路线,并实现了全细胞催化尿苷制备假尿苷。首先,质粒过表达内源的假尿苷-5-磷酸糖苷酶、核糖激酶和核糖核苷水解酶,构建出尿苷到假尿苷的代谢途径,实现了假尿苷的积累;然后,筛选内源的高活性核糖核苷水解酶,促进了尿苷的水解,为假尿苷的合成提供了更多前体;接着,对底物与产物的转运途径进行改造,提升假尿苷产量的同时避免了副产物尿苷的积累。最终获得的重组菌株Ψ-7在24 h内可以全细胞催化30 g/L尿苷产生27.24 g/L假尿苷,转化率为90.8%,生产效率为1.135 g/(L·h),假尿苷产量和生产效率为现有酶催化法报道的最高值。

关键词：假尿苷大肠杆菌全细胞催化假尿苷-5-磷酸糖苷酶核糖激酶核糖核苷水解酶

STABILITY　OF　WHISKERS　AND　INTERFACIAL　MICROSTRUCTURE　IN　ALUMINUM　MATRIX　COMPOSITES　REINFORCED　BY　K_2O·8TiO_2　WHISKERS

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Acta Metallurgica Sinica(English Letters) 1995年第3期8卷 167-173页

作者： LI Jihong ning xiaoguang YE Hengqiang (Laboratory of Atomic Imaging of Solids,Institute of Metal Research, Chinese Academy of Sciences, Shenyang) SHEN Baoluo LI Wei TU Mingjing (Chengdu University of Science and Technology, Chengdu, China) Inst of Metal Research Chinese Acad of Sciences Shenyang China

The stability of K_2O·8TiO_2 whiskers and the microstructures of the interfaces in K_2O·8TiO_2 whisker reinforced ZL109 aluminum composites under different heat treatment conditions were investigated by means of transmission electron microscopy(TEM) , mostly by high resolution TEM( HRTEM). It was found that K_2O·8TiO_2 whiskers were not very stable.The edge of the whiskers decomposed and a TiO interfacial layer formed during the process of fabricating K_2O·8TiO_2/ ZL109Al composite,and so the interior with increasing temperature and time of heatreatment. Two kinds of interfacial microstructures between the whiskers and the matrix were characterized; one was the TiO layer and the other was a nano scale amorphous transition layer. A few MgAl_2O_4 particles were also observed at the whisker/ matrix interfaces.

关键词： potassium titanate whisker,aluminium alloy composite interface heat treatment

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破碎围岩巷道锚注支护参数优化及应用

煤矿安全 2024年第3期55卷 181-189页

作者：刘森虎宁建国史新帅张文刘尚明解小光山东科技大学能源与矿业工程学院山东青岛266590 山东新河矿业有限公司山东济宁272200 枣庄矿业集团新安煤业公司山东微山277500

针对新河矿业730采区南部轨胶联络巷围岩松散破碎、变形严重情况,利用Comsol Multiphysics有限元分析软件探讨了不同注浆参数对浆液扩散的影响;并在此基础上,研究不同注浆锚索布置形式对注浆效果的影响。结果表明:浆液扩散半径会随着注... 详细信息

针对新河矿业730采区南部轨胶联络巷围岩松散破碎、变形严重情况,利用Comsol Multiphysics有限元分析软件探讨了不同注浆参数对浆液扩散的影响;并在此基础上,研究不同注浆锚索布置形式对注浆效果的影响。结果表明:浆液扩散半径会随着注浆压力增大、注浆时间延长而逐渐增大,每增大1 MPa注浆压力浆液扩散半径平均增长率为30.95%,每延长1 min注浆时间,浆液扩散半径平均增长率为25.67%;注浆锚索的布置形式决定了注浆加固圈的范围,当采用“六边形”布置方式时,其注浆加固圈范围相对较大,且顶板两侧不会出现漏浆的情况。基于数值模拟结果,确定了新河矿业南部轨胶联络巷锚注支护的注浆压力为4 MPa、注浆时间为8 min,注浆锚索布置方案为“六边形”式。工程应用表明:优化后的注浆参数有效地控制了巷道围岩的变形与破坏,取得了良好的工程效果,同时也为此类巷道的注浆加固提供了有效依据。

关键词：破碎围岩锚注支护注浆加固围岩控制数值模拟浆液扩散注浆锚索

Online Junction Temperature Measurement of Double-sided Cooling IGBT Power Module through On-state Voltage with High Current

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Chinese Journal of Electrical Engineering 2022年第4期8卷 104-112页

作者： xiaoguang Chai Puqi ning Han Cao Dan Zheng Huakang Li Yunhao Huang Yuhui Kang Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China Wuxi Power Supply Company of State Grid Wuxi 214026China

The aim of this study is to achieve online monitoring of the junction temperature of double-sided-cooling insulated gate bipolar transistor(IGBT)power modules by using the on-state voltage under a high current to maximize the utilization of IGBT power chips.Online junction temperature measurement plays an important role in improving the reliability of the inverter with IGBT,increasing the power density of the motor controller of electric vehicles,and reducing the cost of electric vehicles.

关键词： Double-sided-cooling IGBT junction temperature monitoring on-state voltage with high current

Decompression and fusion combined with rehabilitation training for the foot drop secondary to lumbar degenerative disease:Case report and literature review

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Medicine in Novel Technology and Devices 2022年第4期16卷 137-140页

作者： Nan Li xiaoguang Han ning Zhang Da He Department of Spine Surgery Beijing Jishuitan HospitalPeking UniversityBeijingChina Fourth Clinical Medical College of Peking University BeijingChina

Foot drop(FD)secondary to lumbar degenerative disease is a relatively uncommon finding in spinal practice.Although only a part of patients with FD can obtain satisfactory recovery of their muscle strength after operation,most of the articles still advocate surgical intervention at early stage.Despite the double roots compression is one of the accepted causes for FD,we describe an extremely rare case of a middle-age man presenting with a severe foot drop(tibialis anterior=0/5)resulted from three roots compression(L4-S1),who had undergone pedicle screws fixation(L3-S1),transforaminal lumbar interbody fusion(TLIF)at L4/5,laminotomy and discectomy at L5/S1 with laminotomy at L3/4 as well as conventional rehabilitation training postoperatively,which included strength training of the active and antagonistic muscles in the week lower extremity.Twelve months after surgery,the patient recovered from his deficit(tibialis anterior improved from 0/5 to 4/5).Therefore,we discuss the possible pathological mechanism and surgical option for the foot drop due to the lumbar degenerative disease as well as the potential risk factors portending prognosis postoperatively.

关键词： Foot drop Lumbar degenerative disease Prognosis Rehabilitation