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Effect of Auxiliary Gas Flow Parameters on microstructure and Properties of Ta Coatings Prepared by Three-Cathode Atmosphere Plasma Spraying

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Journal of Beijing Institute of Technology 2022年第3期31卷 302-316页

作者： Jing Cui Haiyang Xia lang Cui Guang Liu College of Aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China China Civil Aviation Ground Special Equipment Research Base Tianjin 300300China Ningbo Branch of Chinese Academy of Ordnance Science Ningbo 315103ZhejiangChina

Based on the three-cathode plasma spraying system,tantalum(Ta)coatings were pre-pared on the substrate of CuCrZr *** effects of different auxiliary gas(helium)flow rates on the microstructure,phase composition,mechanical and wear resistance properties of Ta coatings were *** results showed that the oxidation degree of the coatings decreases first and then increases with the increase of the auxiliary gas *** the auxiliary gas flow rate is 70 L·min-1,the oxidation degree of the coating is the lowest,minimum value of the porosity is 0.21%,and the bonding strength reaches the maximum,59.3 *** this time,the coating wear rate is 0.0012 mm^(3)·N^(-1)·m^(-1)with the best wear *** indicates that the auxiliary gas flow has an important influence on the quality and surface mechanical properties of tantalum coating.

关键词： plasma spraying tantalum(Ta)coating auxiliary gas flow rate bonding strength tri-bological property

Preparation of W-TiC alloys from core-shell structure powders synthesized by an improved wet chemical method

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Rare metals 2023年第4期42卷 1378-1386页

作者： Shao-Ting lang Qing-Zhi Yan Ning-Bo Sun Xiao-Xin Zhang Institute of Nuclear materials University of Science and Technology BeijingBeijing100083China

In order to improve the homogeneous distribution of the TiC particles and facilitate the TiC particles to distribute in the tungsten grain interiors,two kinds of TiCdoped tungsten precursors with a core-shell structure were prepared by an improved wet chemical method at different reaction temperature ***,fine platelike precursor(200-400 nm)and flower-like precursor(approximately 1.25μm)are *** reduction and sintering,the microstructures of the samples were characterized by scanning electron microscopy and transmission electron *** the sample sintered from the platelike precursor,TiC particles with sizes in the range of40-300 nm and an average size of approximately 80 nm were uniformly distributed in the tungsten matrix with a high share in the grain ***,in the sample sintered from the flower-like precursor,the TiC particles with sizes in the range of 50-700 nm are significantly aggregated and non-uniformly distributed in the tungsten *** a result,the sample sintered from the plate-like precursor achieves higher mechanical properties and a much narrower range of bending strength values than that sintered from the flower-like *** average bending strength of the sample sintered from the plate-like precursor is 655 mPa,which is higher than that of the sample sintered from the flower-like precursor(524 mPa).Different reaction mechanisms and dispersing stabilities of the TiC particles at different temperature conditions should be accounted for the differences between the two samples.

关键词： Wet chemical method W-TiC alloy Core-shell structures Spark plasma sintering microstructure characterization

Heat Storage/Heat Release of Phase-Change Filling Body with Casing Heat Exchanger for Extracting Geothermal Energy

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Journal of Thermal Science 2023年第3期32卷 1171-1189页

作者： ZHANG Xiaoyan XU muyan LIU lang YANG Qixing KI-IL Song Energy School Xi'an University of Science and TechnologyXi'an 710054China Key Laboratory of Western mines and Hazards Prevention Ministry of Education of ChinaXi'an 710054China Department of Civil Engineering Inha UniversityIncheon 402-751South Korea

Arranging heat exchanger in filling body to extract geothermal energy is an effective way to alleviate the problems of high ground pressure and high ground temperature in deep resource *** body with casing heat exchanger was acted as research object,encapsulating phase change materials(PCms)in annular *** heat storage and heat release process,the effects of different PCms on temperature distribution,phase-change process and heat transfer performance were *** result indicates:During heat storage process,the temperature increases rapidly and the melting process is accelerated for the position closer surrounding ***_(2)·6H_(2)O/EG can make filling body complete heat storage process in the shortest time because of its good thermal *** heat storage capacity of PCms backfill is significantly higher than that of ordinary backfill;it increases by 36.6%-67.3%at heat storage of 10 *** heat release process,the closer to the heat exchange tube,the greater the temperature drop in filling *** maximum value of heat release rate and heat release capacity is in CaCl_(2)·6H_(2)O/EG backfill,it can release 116.4%more heat than RT35backfill after heat release of 12 h,the maximum value of effectiveness and its heat transfer rate also is in CaCl_(2)·6H_(2)O/EG *** paper provides the basic data for the selection of PCms in phase-change thermal storage filling body.

关键词： flling body heat exchanger phase change material heat storage/heat release

Clones or no clones：genetic structure of riparian Populus euphratica forests in Central Asia

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Journal of Arid Land 2018年第5期10卷 750-766页

作者： Katja KRAmP Thomas SCHmITT Petra lang michael JESCHKE Philipp SCHAFERI Dustin KULANEK ZHANG Ximing YU Ruide Frank m THOmAS Senckenberg German Entomological Institute Eberswalder StraBe 90 Muncheberg 15374 Germany Department of Zoology Faculty Natural Sciences I Institute of Biology Martin Luther University Halle-Wittenberg Halle (SaMe) 06099 Germany Faculty of Regional and Environmental Sciences University of Trier Campus II BehringstraBe 21 Trier 54296 Germany Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Sino-German Joint Research Center for the management of Ecosystems and Environmental Changes in Arid Lands (mEECAL) Urumqi 830011 China

many riparian（Tugai） forests growing along rivers in arid and hyper-arid regions of Central Asia are dominated by the Euphrates poplar（Populus euphratica）. Besides generative reproduction, which is only possible upon flooding events and at a distance to the groundwater of less than 2 m, this phreatophytic tree species also reproduces vegetatively by forming clones that can cover land surface areas of several hectares. Along a gradient of groundwater distances, we investigated whether the fraction of clones in P. euphratica stands（1） increases with increasing distance to the water table;（2） is higher if supplied with water via river cut-offs; and（3） approaches 100% at a short distance to the groundwater, but at high salt concentrations in the upper soil layers, which would prevent germination and establishment of seedlings. AFLP（Amplified Fragment Length Polymorphism） analyses were conducted on leaf samples taken from mature P. euphratica trees growing at the fringes of the Taklimakan Desert in stands with different distances（2–12 m） to the groundwater at two plots at the middle and the lower reaches of the Tarim River and in a stand close to Ebinur Lake, Xinjiang, China. Genetic diversity was large among plots, but considerably smaller within plots. We found the highest genetic diversity（caused by regeneration from seeds） at plots that have a short distance to the groundwater or are supplied with additional water. There was no significant relationship between groundwater distance and clonal fraction. All investigated trees at the saline Ebinur Lake site belonged to one single clone. Our results demonstrate that the genetic pattern of this widespread species is not easily predictable even over small distances as it is a result of a complex interplay of stand history and dispersal of propagules（pollen, seeds, and vegetative diaspores） by wind and water. In conservation and restoration schemes, P. euphratica stands with a high genetic diversity and stands that grow at

关键词： clonality floodplain forest ground water phreatophyte population genetics rejuvenation salinity

Variation of iron species in sliding mud

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Chinese Science Bulletin 2002年第23期47卷 2018-2024页

作者： Guodong Zheng Sheng Xu Yuhua lang Zifang meng Chinese Acad Sci State Key Lab Gas GeochemLanzhou Inst GeolLanzhou 730000China

Results of mossbauer spectroscopy and ICP-AES measurement revealed a special distribution pattern of iron species in four crossing profiles of the Tertiary Formation Type of Landslides in Japan. In comparison with host rocks, the sliding mud in the landslide slip zone contains the higher ferrous iron content and/or trace pyrite, which indicates that the forming environment was relatively reducing. The total iron content also increased with an increase in ferric iron and pyrite, in contrast, decreased with an increase in ferrous iron content. The deep-gray and black mud layers formed and accumulated in various volumes within landslide slip zones are treated as the basic criteria for the slipping activity, because the soft mud saturated with groundwater is easy to create a plastic deformation.

关键词： sliding mud mossbauer spectroscopy iron speciation total iron slip zone redox condition

丁酸钠通过G蛋白偶联受体41介导蛋白激酶B/哺乳动物雷帕霉素靶蛋白信号通路刺激牛乳腺上皮细胞增殖

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动物营养学报 2024年第3期36卷 1878-1891页

作者：张静卜丽君郎姣姣刘亚鹏夏呈强霍文婕刘强山西农业大学动物科学学院太谷030801

本试验旨在研究丁酸钠(SB)刺激牛乳腺上皮细胞(BmECs)增殖的分子机制。采用单因素设计,以含不同浓度(0、15、30、45、60和75μmol/L)SB的DmEm/F12培养基(含10%新生胎牛血清)培养BmECs,通过细胞计数试剂盒(CCK⁃8)检测细胞活性,确定适宜S... 详细信息

本试验旨在研究丁酸钠(SB)刺激牛乳腺上皮细胞(BmECs)增殖的分子机制。采用单因素设计,以含不同浓度(0、15、30、45、60和75μmol/L)SB的DmEm/F12培养基(含10%新生胎牛血清)培养BmECs,通过细胞计数试剂盒(CCK⁃8)检测细胞活性,确定适宜SB浓度。然后以对照(0μmol/L)和适宜SB浓度培养BmECs,并采用蛋白激酶B(Akt)阻断剂(AKT⁃IN⁃1)、哺乳动物雷帕霉素靶蛋白(mTOR)阻断剂雷帕霉素(Rap)或小干扰RNA(siR⁃NA)沉默G蛋白偶联受体41(GPR41)对信号通路及受体进行处理,检测BmECs细胞增殖、凋亡以及GPR41和Akt/mTOR信号通路相关基因和蛋白表达的变化。结果表明:1)与对照组相比,60μmol/L的SB显著提高了BmECs细胞活力(Pmol/L的SB显著抑制了BmECs细胞活力(Pmol/L的SB极显著增加了增殖细胞核抗原(PCNA)、细胞周期蛋白A2(CCNA2)和细胞周期蛋白D1(CCND1)的mRNA相对表达量(Pmol/L SB显著或极显著提高了B细胞淋巴瘤2(BCL2)的mRNA和蛋白相对表达量及BCL2/B细胞淋巴瘤2相关X蛋白(BAX)比值(PmRNA和蛋白相对表达量(PmTOR)/mTOR比值(Pmol/L的SB对Akt和mTOR信号通路的激活被AKT⁃IN⁃1极显著阻断(PmTOR完全逆转了60μmol/L SB对BmECs增殖的促进作用以及增殖基因和蛋白表达的改变(PmRNA或蛋白表达(P>0.05)。3)与对照组相比,60μmol/L的SB极显著提高了GPR41的mRNA相对表达量(Pmol/L SB对BmECs增殖的促进作用以及Akt/mTOR信号通路相关的增殖基因和蛋白的mRNA或蛋白表达(Pmol/L SB可通过GPR41介导Akt/mTOR信号通路促进BmECs增殖。

关键词： Akt mTOR 信号通路牛乳腺上皮细胞增殖丁酸钠

新媒体时代高校爱国主义教育效果提升策略研究

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教育教学论坛 2024年第30期 169-172页

作者：刘明强常宁白琳琅青岛理工大学人文与外国语学院山东青岛266520

开展爱国主义教育,是高校着力培养担当民族复兴大任时代新人的重要举措之一。新媒体时代下,教育载体的更新、教育环境的变化给高校爱国主义教育工作带来机遇的同时,新媒体平台利用不完善、教育内容不新颖、师生媒介素养有待提高等问题... 详细信息

开展爱国主义教育,是高校着力培养担当民族复兴大任时代新人的重要举措之一。新媒体时代下,教育载体的更新、教育环境的变化给高校爱国主义教育工作带来机遇的同时,新媒体平台利用不完善、教育内容不新颖、师生媒介素养有待提高等问题逐渐凸显,严重制约着高校爱国主义教育成效。高校如何利用新媒体使爱国主义教育“活”起来,增强爱国主义教育的实效性,成为时代使命和亟须解决的重要命题。高校须完善校园新媒体网络建设,净化大学生网络爱国空间;深化爱国主义教育课堂改革,引导大学生自主理性爱国;丰富爱国主义教育实践活动,强化大学生爱国报国行为,增强高校爱国主义教育效果,促进高校爱国主义教育的高质量发展。

关键词：爱国主义教育新媒体网络教育效果

基于铁电-顺电相变增强全固态锂电池高温安全性的新设计

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Science Bulletin 2024年第1期69卷 22-25页

作者：李文儒崔龙飞公天宇张育涵刘跃辉鞠江伟黄浪马君崔光磊 Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101China Shandong Energy Institute Qingdao 266101China Qingdao New Energy Shandong Laboratory Qingdao 266101China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China

All-solid-state lithium batteries(ASSLBs)utilizing a nonflowing and low-flammable solid-state electrolyte are considered the most promising candidate to tackle the safety issue of stateof-the-art lithium ion batteries[1].However,recent studies have revealed that ASSLBs may not be as safe as *** high temperatures,various aging and degradation processes evolve inside ASSLBs,such as electrode decay,electrolyte decomposition。

关键词：全固态锂电池高温安全性 electrolyte

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高速率连续波泥浆脉冲解码试验管线仿真分析

石油矿场机械 2024年第5期53卷 6-14页

作者：张良王智明韩虎田博辉中海油田服务股份有限公司油田技术事业部北京101149 长江大学石油工程学院湖北武汉430100

随着国内深井、超深井钻探需求增加,连续波泥浆脉冲技术正向远距离、高速率方向发展。中海油服自主搭建了地面6000 m泥浆循环试验系统,由于测试仪器上游采用50.8 mm软管,管线压耗大且变径反射干扰严重,远距离高速率解码试验研究受限。... 详细信息

随着国内深井、超深井钻探需求增加,连续波泥浆脉冲技术正向远距离、高速率方向发展。中海油服自主搭建了地面6000 m泥浆循环试验系统,由于测试仪器上游采用50.8 mm软管,管线压耗大且变径反射干扰严重,远距离高速率解码试验研究受限。针对此问题,基于试验系统建立了简化脉冲器-管线数值模型,研究50.8 mm软管对连续波信号的影响规律,并通过解码试验验证。研究结果表明:测试仪器上游50.8 mm软管与循环管线存在扩径,产生的反射波与发生波叠加导致波形畸变,且随着频率升高,发生波畸变越严重。50.8 mm软管内径小,管线沿程摩阻压降大,压力波的传输衰减程度高于等长的地下直管。50.8 mm软管换成101.6 mm软管,消除变径反射和降低沿程摩阻压降后,低频压力波波形改善,传输后幅值提高75%以上,有效降低了解码误码率。地面6000 m管线解码试验传输速率从6 bps提高至8 bps,验证了数值仿真分析结果。

关键词：深井连续波泥浆脉冲传输速率 2FSK 压力波畸变数值仿真