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HUAYI ELEC.APPARATUS GROUP CO.,LTD.
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《China's Foreign Trade》 2002年第6期39-39,共1页
Huayi Elec. Apparatus Group Co, Ltd. (HEAG), China, is a manufacturer of H.V. & L.V. switchgear equipments appointed by state, a certified enterprise of ISO9001 Quality Assurance System, the Golden Customer of the... Huayi Elec. Apparatus Group Co, Ltd. (HEAG), China, is a manufacturer of H.V. & L.V. switchgear equipments appointed by state, a certified enterprise of ISO9001 Quality Assurance System, the Golden Customer of the Agriculture Bank of China in Zhejiang province, National Advanced Unit of Science and Technology, High and New Technology Enterprise in Zhejiang province, etc., which mainly produces the complete set of equipment, Distribution 展开更多
关键词 LTD HUAYI elec.apparatus GROUP CO OVER
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Huayi Elec.Apparatus Group Co,Ltd.
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《China's Foreign Trade》 2002年第4期28-28,共1页
关键词 CO OVER Huayi elec.apparatus Group Co Ltd
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HUAYI ELEC.APPARATUS GROUP CO.,LTD.
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《China's Foreign Trade》 2002年第12期37-37,共1页
Huayi Elec. Apparatus Group Co, Ltd. (HEAG), China, is a manufacturer of H.V. & L.V. switchgear equipmentsappointed by state, a certified enterprise of ISO9001 Quality Assurance System, the Golden Customer of the ... Huayi Elec. Apparatus Group Co, Ltd. (HEAG), China, is a manufacturer of H.V. & L.V. switchgear equipmentsappointed by state, a certified enterprise of ISO9001 Quality Assurance System, the Golden Customer of the AgricultureBank of China in Zhejiang province, National Advanced Unit of Science and Technology, High and New TechnologyEnterprise in Zhejiang province, etc., which mainly produces the complete set of equipment, Distribution AutomaticSwitches under 35kV and their terminal devices, H.V. components for switchgear, electronic watt-hour meter etc.All the leading products have been selected in 【Catalogue of the Recommended Enterprises for Two Networks’ 展开更多
关键词 LTD HUAYI elec.apparatus GROUP CO
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中医适宜技术联合盆底肌肉训练治疗产后压力性尿失禁临床观察 被引量:2
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作者 沈妍姝 《中国中医药现代远程教育》 2024年第3期88-90,共3页
目的 对产后压力性尿失禁患者进行中医适宜技术干预治疗,并观察效果。方法 将60例患者随机分为治疗组和训练组,并对其进行相应治疗,观察2组1 h尿垫试验结果、Sandvik尿失禁指数和国际尿失禁咨询委员会尿失禁问卷简表(ICI-Q-SF)评分改善... 目的 对产后压力性尿失禁患者进行中医适宜技术干预治疗,并观察效果。方法 将60例患者随机分为治疗组和训练组,并对其进行相应治疗,观察2组1 h尿垫试验结果、Sandvik尿失禁指数和国际尿失禁咨询委员会尿失禁问卷简表(ICI-Q-SF)评分改善情况,以及临床疗效。结果 治疗后,治疗组1 h尿垫试验结果、Sandvik尿失禁指数和ICI-Q-SF评分改善均优于训练组。治疗结束时,治疗组总有效率为86.7%(26/30),高于对照组的63.3%(19/30)(P<0.05)。6个月随访时治疗组总有效率86.7%(26/30)亦高于对照组的56.7%(17/30)(P<0.05)。结论 在产后女性中,压力性尿失禁的发生是值得关注的问题。将中医适宜技术与凯格尔训练联用干预产后压力性尿失禁达到巩固、延长疗效的目的。 展开更多
关键词 压力性尿失禁 产后 中医适宜技术 雷火灸 电针 凯格尔训练 中医外治法
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纳米TiO_(2)改性纤维素纸板在油流环境下的带电特性研究
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作者 刘道生 王广康 牛腾霄 《高压电器》 CAS CSCD 北大核心 2024年第2期169-177,共9页
经纳米TiO_(2)改性纤维素纸板可以增强其击穿场强与抗老化性能,是当前电气绝缘领域研究的热点。纸板中添加纳米粒子对于变压器油流带电影响仍不明确;因此,为了揭示纳米粒子对油流带电影响与抑制机理,需测量与分析纳米改性纸板中的油流... 经纳米TiO_(2)改性纤维素纸板可以增强其击穿场强与抗老化性能,是当前电气绝缘领域研究的热点。纸板中添加纳米粒子对于变压器油流带电影响仍不明确;因此,为了揭示纳米粒子对油流带电影响与抑制机理,需测量与分析纳米改性纸板中的油流带电特性。文中以TiO2改性纸板与未改性矿物油为研究对象,通过旋转圆盘系统测量其摩擦产生的静电电流。根据控制变量法研究了温度、纳米粒子质量分数和流速等因素对带电程度的影响,分析了纳米粒子对于油流带电影响机理;采用有限元分析方法分析了变压器油道仿真模型,对比了不同质量分数下的纳米TiO_(2)改性纸板制作的油道模型内部电场分布情况。研究结果表明:与未改性纸板相比,纤维素基体中添加质量分数为1%的纳米TiO_(2)粒子可以抑制油流带电程度,使得油道内部积累电荷后的电场分布畸变程度最小。研究结果可以为抑制变压器中的油流带电提供新方法。 展开更多
关键词 纳米改性 油流带电测量 有限元分析 绝缘纸板 电场分布
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电臂尺寸和安装条件对热电模块力学性能的影响
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作者 孟凡凯 周林 +1 位作者 孙悦桐 刘寅 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第10期124-135,共12页
针对热电制冷模块中热电臂尺寸对模块整体热应力场的影响,以C-31106型热电制冷模块为研究对象,建立由31对热电偶组成的热-电-力学耦合多物理场模型.采用有限元仿真方法,考虑钎料层的存在并引入表征黏塑性材料的Anand修正本构方程,建立3... 针对热电制冷模块中热电臂尺寸对模块整体热应力场的影响,以C-31106型热电制冷模块为研究对象,建立由31对热电偶组成的热-电-力学耦合多物理场模型.采用有限元仿真方法,考虑钎料层的存在并引入表征黏塑性材料的Anand修正本构方程,建立3种安装条件下的热电模型,分析不同电流下热电臂高度和截面边长对热电模块温度场和力学性能的影响规律.结果表明,当热电臂处于最佳高度时,在给定范围内热电臂截面边长越大,越有利于提高热电模块力学可靠性,当工作电流为2.6 A,截面边长从0.99 mm增加到1.09 mm时,冷、热端的最大von Mises应力分别减小了74.67%和22.60%.对模块冷端和热端分别采用固定约束和机械压装的安装方式可有效提高热电模块的力学可靠性,当采用上述安装方式时,冷、热端的最大von Mises应力相比两端只采用固定约束的安装方式分别减小了48.76%和74.02%. 展开更多
关键词 热电制冷 制冷器 安装条件 黏塑性材料 热-电-力学耦合 有限元法
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SM2可链接环签名在匿名电子投票系统中的应用
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作者 李启南 邹楷文 《河南科技》 2024年第20期20-25,共6页
【目的】针对匿名电子投票中签名算法非国产化、身份隐私泄露、重复投票、投票结果提前泄露的安全性问题,提出了基于SM2可链接环签名的匿名电子投票系统。【方法】以SM2可链接环签名作为选票中的身份凭证,保证投票者身份匿名,同时规避... 【目的】针对匿名电子投票中签名算法非国产化、身份隐私泄露、重复投票、投票结果提前泄露的安全性问题,提出了基于SM2可链接环签名的匿名电子投票系统。【方法】以SM2可链接环签名作为选票中的身份凭证,保证投票者身份匿名,同时规避了选票被伪造的可能,实现投票者身份和选票的全过程匿名性;使用匿名地址来隐藏选票内容,避免投票结果提前泄露,实现投票的公正性和候选人身份匿名;利用SM2可链接环签名的可链接性来防止重复投票,实现投票的不可重复性;应用FISCO BCOS智能合约来完成计票过程,避免传统可信第三方的约束,实现投票的公平性。【结果】该设计满足电子投票的七大基本属性,实现了匿名电子投票系统的全流程国密替代,丰富了SM2可链接环签名的应用场景。【结论】SM2可链接环签名能替代国际通用环签名,实现应用系统环签名国产化。 展开更多
关键词 SM2可链接环签名 国密算法 隐私保护 匿名电子投票 匿名地址
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不同粒径零价铁对微氧脱氮系统的影响 被引量:1
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作者 于雅楠 张潇 +4 位作者 岳秀萍 赵博玮 周爱娟 崔颖 邢剑波 《工业水处理》 CAS CSCD 北大核心 2024年第4期84-97,共14页
构建了部分硝化反硝化厌氧氨氧化(SNAD)微氧体系,并定期向体系内投加120 mg不同粒径的零价铁(ZVI),从反应器运行情况、微生物性能以及群落结构来探究不同粒径ZVI对微氧系统的影响。研究结果表明,在50 nm粒径ZVI(50 nZVI)的介导下,系统的... 构建了部分硝化反硝化厌氧氨氧化(SNAD)微氧体系,并定期向体系内投加120 mg不同粒径的零价铁(ZVI),从反应器运行情况、微生物性能以及群落结构来探究不同粒径ZVI对微氧系统的影响。研究结果表明,在50 nm粒径ZVI(50 nZVI)的介导下,系统的TIN去除率最终稳定在83.591%,电子传递活性(ETSA)是接种污泥的1.48倍,均高于其他粒径ZVI的影响。越小粒径ZVI越能促进胞外聚合物的产生,有利于活性污泥结构稳定。这都源于粒径越小的ZVI更容易被微生物吸附、利用。微生物群落结构与功能分析结果表明,在粒径越小的ZVI介导下的微生物群落多样性越高,群落结构也越复杂。ZVI介导会促进对氧需求不敏感的微生物的富集,样品中主要检测出Candidatus_Brocadia和Candidatus_Kuenenia两种厌氧氨氧化菌(AnAOB),且在50 nZVI影响下丰度最高,分别为4.650%和0.692%。nZVI介导下,AnAOB与Gemmobacter和norank_f_Comamonadaceae两种兼性厌氧型反硝化菌共同作用构成SNAD的脱氮途径。而在mZVI介导下,兼性厌氧型反硝化为主要脱氮途径。 展开更多
关键词 微氧 部分硝化反硝化厌氧氨氧化系统 零价铁 电子传递活性 生物脱氮
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A multifunctional shear apparatus for rocks subjected to true triaxial stress and high temperature in real-time 被引量:1
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作者 Jun Zhao Xia-Ting Feng +2 位作者 Jia-Rong Wang Liang Hu Yue Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3524-3543,共20页
Deep engineering disasters,such as rockbursts and collapses,are more related to the shear slip of rock joints.A novel multifunctional device was developed to study the shear failure mechanism in rocks.Using this devic... Deep engineering disasters,such as rockbursts and collapses,are more related to the shear slip of rock joints.A novel multifunctional device was developed to study the shear failure mechanism in rocks.Using this device,the complete shearedeformation process and long-term shear creep tests could be performed on rocks under constant normal stiffness(CNS)or constant normal loading(CNL)conditions in real-time at high temperature and true-triaxial stress.During the research and development process,five key technologies were successfully broken through:(1)the ability to perform true-triaxial compressioneshear loading tests on rock samples with high stiffness;(2)a shear box with ultra-low friction throughout the entire stress space of the rock sample during loading;(3)a control system capable of maintaining high stress for a long time and responding rapidly to the brittle fracture of a rock sample as well;(4)a refined ability to measure the volumetric deformation of rock samples subjected to true triaxial shearing;and(5)a heating system capable of maintaining uniform heating of the rock sample over a long time.By developing these technologies,loading under high true triaxial stress conditions was realized.The apparatus has a maximum normal stiffness of 1000 GPa/m and a maximum operating temperature of 300C.The differences in the surface temperature of the sample are constant to within5C.Five types of true triaxial shear tests were conducted on homogeneous sandstone to verify that the apparatus has good performance and reliability.The results show that temperature,lateral stress,normal stress and time influence the shear deformation,failure mode and strength of the sandstone.The novel apparatus can be reliably used to conduct true-triaxial shear tests on rocks subjected to high temperatures and stress. 展开更多
关键词 True-triaxial shear apparatus ROCKS Complete shear stress-deformation process CREEP Real-time high-temperature
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混凝土环境中β-甘油磷酸钠影响钢筋阻锈行为研究
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作者 王潇舷 刘加平 +2 位作者 穆松 金鸣 马麒 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第3期28-40,共13页
在混凝土高碱环境中,为了提高混凝土中钢筋抗氯离子侵蚀能力,采用新型环保型有机阻锈剂——β-甘油磷酸钠保护钢筋,达到延长钢筋混凝土结构整体寿命的目的。本文通过采用电化学方法对该种有机阻锈剂作用下,不同阳离子类型的模拟孔溶液... 在混凝土高碱环境中,为了提高混凝土中钢筋抗氯离子侵蚀能力,采用新型环保型有机阻锈剂——β-甘油磷酸钠保护钢筋,达到延长钢筋混凝土结构整体寿命的目的。本文通过采用电化学方法对该种有机阻锈剂作用下,不同阳离子类型的模拟孔溶液中钢筋性能演变过程进行实时监测,并获取相应的关键参数,探究了钝化时期β-甘油磷酸钠与钢筋钝化膜,以及维钝时期,β-甘油磷酸钠、钢筋钝化膜与氯离子之间的作用关系,揭示了该种有机物的阻锈机制。通过OCP、LPR以及EIS电化学测试方法得到的结果表明:β-甘油磷酸钠与钝化膜中Fe氧化物/氢氧化物通过物理化学作用进行结合,使得钢筋表面形成阻锈能力更强的保护膜,从而提高了钢筋抗氯离子侵蚀能力。4种模拟孔溶液中钢筋抗氯离子侵蚀能力分别为NaOH+0.1 mol/Lβ-甘油磷酸钠>饱和澄清Ca(OH)_(2)>NaOH>饱和澄清Ca(OH)_(2)+0.1 mol/Lβ-甘油磷酸钠;其中,NaOH,NaOH+0.1 mol/Lβ-甘油磷酸钠与饱和澄清Ca(OH)_(2)溶液中钢筋相应的临界氯离子浓度(c_(crit))分别为0.02、0.07、0.04 mol/L,而饱和澄清Ca(OH)_(2)+0.1 mol/Lβ-甘油磷酸钠中钢筋未生成有效钝化膜。除此之外,β-甘油磷酸钠加入以Na^(+)为主的模拟孔溶液中,将促进钢筋表面形成更致密的钝化膜,钝化膜形成速率更快,即在72 h就可形成80%以上钝化膜,阻锈效率则高达99.80%;进一步对比分析Na^(+)与Ca^(2+)溶液自身对钢筋抗氯离子侵蚀能力的影响可知,Ca^(2+)溶液更有利于抵抗氯离子侵蚀能力,阻锈效率达到90%以上。 展开更多
关键词 混凝土模拟孔溶液 β-甘油磷酸钠 钝化膜 氯离子 电化学行为
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从《黄帝内经》“九针之宜,各有所为”思想浅论罐具在拔罐中的作用
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作者 刘尚瑾 吴国庆 +2 位作者 高振华 汪唐顺 李瑞 《湖南中医药大学学报》 CAS 2024年第8期1433-1437,共5页
罐具是拔罐的载体,发展到当代罐具种类丰富,使用不同罐具拔罐所产生的刺激量不同,发挥的治疗效应亦有差异。临床上应当根据不同的病证选择不同的罐具,但对罐具性能功用的论述尚不成熟。《黄帝内经》中记载用于针灸临床的多种针具被称为... 罐具是拔罐的载体,发展到当代罐具种类丰富,使用不同罐具拔罐所产生的刺激量不同,发挥的治疗效应亦有差异。临床上应当根据不同的病证选择不同的罐具,但对罐具性能功用的论述尚不成熟。《黄帝内经》中记载用于针灸临床的多种针具被称为九针,从九针的长短形状规格论述了不同针具在刺激层次与刺激量上的差异,提出不同针具治疗效果、适应病证有所不同的“九针之宜,各有所为”理论。在此思想的启发下,讨论罐具的大小规格材质等方面对拔罐作用效应的影响,提出罐具的形质不同,产生的刺激层次、刺激量、治疗效应不同,适应病证的种类亦不同,即“罐具不同,各有所施”,以期为临床上罐具的选择提供参考。 展开更多
关键词 罐具 拔罐 罐法 九针 《黄帝内经》 药罐 竹罐
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自拟温经通络汤治疗腰椎间盘突出症的临床效果
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作者 张华军 方伟 +1 位作者 刘金星 夏安勇 《中国医药导报》 CAS 2024年第15期1-4,共4页
目的 探讨自拟温经通络汤治疗腰椎间盘突出症的临床效果。方法 选取2020年2月至2022年12月四川省眉山市中医医院收治的122例腰椎间盘突出症患者为研究对象,按照随机数字表法将其分为对照组和观察组,各61例。对照组以靶点射频热凝术治疗... 目的 探讨自拟温经通络汤治疗腰椎间盘突出症的临床效果。方法 选取2020年2月至2022年12月四川省眉山市中医医院收治的122例腰椎间盘突出症患者为研究对象,按照随机数字表法将其分为对照组和观察组,各61例。对照组以靶点射频热凝术治疗,观察组增加自拟温经通络汤治疗。两组均治疗3个疗程。评价两组临床疗效。比较两组治疗前后中医症候积分、表面肌电图水平[左侧积分肌电值(iEMG)、右侧iEMG、左侧平均功率频率(MPF)、右侧MPF]、炎症因子水平[基质金属蛋白酶-7(MMP-7)、缺氧诱导因子-2α(HIF-2α)、前列腺素E_(2)(PGE_(2))]及不良反应总发生率。结果 观察组临床疗效优于对照组(P<0.05)。治疗后,两组中医证候积分均低于治疗前,且观察组低于对照组(P<0.05)。治疗后,两组左侧iEMG、右侧iEMG、左侧MPF、右侧MPF均高于治疗前,且观察组高于对照组(P<0.05)。治疗后,两组MMP-7、HIF-2α、PGE_(2)水平均较治疗前降低,且观察组低于对照组(P<0.05)。两组不良反应总发生率比较,差异无统计学意义(P>0.05)。结论 自拟温经通络汤治疗腰椎间盘突出症效果良好,可改善患者中医症候,提高腰椎部肌电图指标水平,抑制炎症因子表达,治疗安全性良好。 展开更多
关键词 腰椎间盘突出症 自拟温经通络汤 中医症候 肌电图 炎症因子
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固态电池硬碳复合负极的制备及其性能研究
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作者 贺晨晨 余海天 +2 位作者 李敏慧 邵钦君 陈剑 《电源技术》 CAS 北大核心 2024年第4期537-549,共13页
固态锂离子电池在安全性和能量密度方面有超过传统锂离子电池的潜力。作为电池的重要组成部分,高性能固态负极的研究和开发具有重要意义。硬碳在充放电过程中的体积变化较小,有利于维持与固体电解质(膜)的物理接触,是固态锂离子电池负... 固态锂离子电池在安全性和能量密度方面有超过传统锂离子电池的潜力。作为电池的重要组成部分,高性能固态负极的研究和开发具有重要意义。硬碳在充放电过程中的体积变化较小,有利于维持与固体电解质(膜)的物理接触,是固态锂离子电池负极材料的首选之一。在电极中构建良好的离子和电子传导网络是制备高性能固态负极的关键。首次利用硬碳为活性物质、锂化的全氟磺酸(Li-Nafion)树脂与Li_(6.4)La_(3)Zr_(1.6)Ta_(0.6)O_(12)(LLZTO)的复合物同时作为粘结剂和电极内部固体电解质研制了固态复合负极。运用电化学测试和XPS表征,探究了固态复合负极中不可逆容量的来源。通过优化复合负极的组成和结构,实现了硬碳复合负极的稳定循环。所研制的固态复合电极在70℃下循环180次的平均库仑效率为99.82%。以Li-Nafion膜作为电池的固体电解质隔膜,将经预锂化处理的硬碳复合负极与磷酸铁锂正极组装了全电池。该电池稳定循环400次,平均库仑效率达99.80%。此外,该复合负极与单晶LiNi_(0.6)Co_(0.1)Mn_(0.3)O_(2)(NCM613)组装的固态软包电池,首次放电比容量以正极材料计为154.4 mAh/g,首次库仑效率为84.66%,充放电循环30次的平均库仑效率为98.51%。 展开更多
关键词 固态电池 复合负极 硬碳 离子导电网络 电极组成
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Small but big leaps towards neuroglycomics:exploring N-glycome in the brain to advance the understanding of brain development and function
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作者 Boyoung Lee Hyun Joo An 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期489-490,共2页
Glycosylation is a process that involves the addition of sugar moieties or glycans to different types of molecules,including proteins,lipids,and nucleic acids.Among these,protein glycosylation is one of the most preva... Glycosylation is a process that involves the addition of sugar moieties or glycans to different types of molecules,including proteins,lipids,and nucleic acids.Among these,protein glycosylation is one of the most prevalent forms of post-translational modification,playing a crucial role in biological complexity.With more than ten monosaccharides identified within mammalian brain cells and more than 1×1012 possible combinations,the heterogeneity of glycosylation is extensive(Conroy et al.,2021).The diversity of glycans and the complexity of their structures allow for a wide range of protein functions.N-glycans are one of the most abundant forms of glycans and are involved in various cellular functions.N-glycans can be added to proteins at specific sequons,Asn-X-Ser/Thr,and are classified into three main types in mature glycoproteins:high mannose,complex,and hybrid.High mannose N-glycans consist of 5-9 mannose residues linked to a chitobiose core and undergo processing into complex or hybrid forms in the Golgi apparatus(Varki et al.,2017).Complex N-glycans are more diverse and contain various branched structures such as antennae with fucose,galactose,and sialic acid residues.Hybrid N-glycans contain one or more complex branches in conjunction with an oligomannose branch(Fisher and Ungar,2016).Understanding the specific functions of these different types of N-glycans in protein regulation,folding,and function is an active area of research in the life sciences,including glycobiology. 展开更多
关键词 functions FUNCTION apparatus
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A novel rapid cooling assembly design in a high-pressure cubic press apparatus
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作者 Peiyan Wu Yongjiang Xu Yanhao Lin 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期98-104,共7页
In traditional high-pressure–temperature assembly design, priority has been given to temperature insulation and retention at high pressures.This limits the efficiency of cooling of samples at the end of experiments, ... In traditional high-pressure–temperature assembly design, priority has been given to temperature insulation and retention at high pressures.This limits the efficiency of cooling of samples at the end of experiments, with a negative impact on many studies in high-pressure Earth andplanetary science. Inefficient cooling of experiments containing molten phases at high temperature leads to the formation of quench textures,which makes it impossible to quantify key compositional parameters of the original molten phase, such as their volatile contents. Here,we present a new low-cost experimental assembly for rapid cooling in a six-anvil cubic press. This assembly not only retains high heatingefficiency and thermal insulation, but also enables a very high cooling rate (∼600 ℃/s from 1900 ℃ to the glass transition temperature).Without using expensive materials or external modification of the press, the cooling rate in an assembly (∼600 ℃/s) with cube lengths of38.5 mm is about ten times faster than that in the traditional assembly (∼60 ℃/s). Experiments yielding inhomogeneous quenched melttextures when the traditional assembly is used are shown to yield homogeneous silicate glass without quench textures when the rapid coolingassembly is used. 展开更多
关键词 CUBIC INSULATION apparatus
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A Novel High Temperature Apparatus for in situ Synchrotron X-ray Diffraction Studies of Molten Salt
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作者 CAO Hui-li GAO Mei +5 位作者 Andebet G.Tamirat ZHAO Hong-bin ZHOU Xing-tai HUANG Yu-ying LEI Qi WEN Wen 《分析测试学报》 CAS CSCD 北大核心 2024年第10期1608-1617,共10页
This study demonstrates the design and application of a novel high temperature rotatory apparatus for insitu synchrotron X-ray diffraction studies of molten salts,facilitating investigation into the interaction betwee... This study demonstrates the design and application of a novel high temperature rotatory apparatus for insitu synchrotron X-ray diffraction studies of molten salts,facilitating investigation into the interaction between various structural materials and molten salts.The apparatus enables accurate detection of every phase change during hightemperature experiments,including strong reaction processes like corrosion.Molten salts,such as chlorides or fluo⁃rides,together with the structure materials,are inserted into either quartz or boron nitride capillaries,where X-ray diffraction pattern can be continuously collected,as the samples are heated to high temperature.The replacement re⁃action,when molten ZnCl2 are etching Ti3AlC2,can be clearly observed through changes in diffraction peak intensity as well as expansion in c-axis lattice parameter of the hexagonal matrix,due to the larger atomic number and ionic ra⁃dius of Zn2+.Furthermore,we investigated the high-temperature corrosion process when GH3535 alloy is in FLiNaK molten salt,and can help to optimize its stability for potential applications in molten salt reactor.Additionally,this high temperature apparatus is fully compatible with the combined usage of X-ray diffraction and Raman technique,providing both bulk and surface structural information.This high temperature apparatus has been open to users and is extensively used at BL14B1 beamline of the Shanghai Synchrotron Radiation Facility. 展开更多
关键词 in-situ X-ray diffraction rotary micro-diffractometer rotary high-temperature apparatus molten salt
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Preparation and Anti⁃arc Erosion Property of Ag Matrix Electrical Contact Material Reinforced by Novel Ti_(2)Cd
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作者 SUN Wanjie SHI Yuxin +4 位作者 DING Jianxiang REN Wanbin PAN Zhixiong ZHANG Peigen SUN Zhengming 《材料导报》 EI CAS CSCD 北大核心 2024年第21期190-196,共7页
Due to their outstanding electrical contact properties,Cd-containing silver-matrix electrical contact materials can meet the requirements of high stability and long life for military defense and aerospace applications... Due to their outstanding electrical contact properties,Cd-containing silver-matrix electrical contact materials can meet the requirements of high stability and long life for military defense and aerospace applications.In order to further reduce the Cd content under the premise of meeting the high-performance requirements,in this study,high-purity intermediate Ti_(2)Cd powder of MAX phase(Ti_(2)CdC)was synthesized with a pressureless technique and then applied to reinforce the Ag matrix.The Cd content of the as-prepared Ag/Ti_(2)Cd composites was actually reduced by 38.31%compared with conventional Ag/CdO material.Based on the systematic study of the effect of heat treatment temperature on the physical phase,morphology,interface and comprehensive physical properties of Ag/Ti_(2)Cd composites,the preferred samples(heat treated at 400°C for 1 h)showed high density(97.77%),low resistivity(2.34μΩ·cm),moderate hardness(90.8HV),high tensile strength(189.9 MPa),and exhibited good electrical contact performance after 40000 cycles of arc discharging under severe conditions(DC 28 V/20 A).The results of microscopic morphological evolution,phase change and elemental distribution of the electrical contact surface show that the combination of high stability of Ti_(2)Cd reinforcing phase,good interfacial bonding with Ag matrix and improved melt pool viscosity in the primary stage of arc erosion,results in low and stable contact resistance(average value 13.20 mΩ)and welding force(average value 0.6 N),low fluctuation of static force(2.2-2.5 N).The decomposition and absorption energy of Ti_(2)Cd and the arc extinguishing effect of Cd vapor are the main reasons for the stable arcing energy and arcing time of electric contacts in the late stage of arc erosion. 展开更多
关键词 low-voltage apparatus Ag matrix composite Ti-Cd compound electrical contact properties arc erosion mechanism
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Analysis of strength characteristics of loess before and after freezing using a hollow cylinder torsional shear apparatus
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作者 Peng Shen QingZhi Wang +2 位作者 JianHong Fang ChenWei Wang Kui Zhang 《Research in Cold and Arid Regions》 CSCD 2024年第2期63-72,共10页
This paper aims to comprehensively analyze the influence of the principal stress angle rotation and intermediate principal stress on loess's strength and deformation characteristics. A hollow cylinder torsional sh... This paper aims to comprehensively analyze the influence of the principal stress angle rotation and intermediate principal stress on loess's strength and deformation characteristics. A hollow cylinder torsional shear apparatus was utilized to conduct tests on remolded samples under both normal and frozen conditions to investigate the mechanical properties and deformation behavior of loess under complex stress conditions. The results indicate significant differences in the internal changes of soil particles, unfrozen water, and relative positions in soil samples under normal and frozen conditions, leading to noticeable variations in strength and strain development.In frozen state, loess experiences primarily compressive failure with a slow growth of cracks, while at normal temperature, it predominantly exhibits shear failure. With the increase in the principal stress angle, the deformation patterns of the soil samples under different conditions become essentially consistent, gradually transitioning from compression to extension, accompanied by a reduction in axial strength. The gradual increase in the principal stress axis angle(α) reduces the strength of the generalized shear stress and shear strain curves.Under an increasing α, frozen soil exhibits strain-hardening characteristics, with the maximum shear strength occurring at α = 45°. The intermediate principal stress coefficient(b) also significantly impacts the strength of frozen soil, with an increasing b resulting in a gradual decrease in generalized shear stress strength. This study provides a reference for comprehensively exploring the mechanical properties of soil under traffic load and a reliable theoretical basis for the design and maintenance of roadbeds. 展开更多
关键词 LOESS Hollow cylinder torsional shear apparatus Major principal stress angle Intermediate principal stress coefficient
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Rock strength weakening subject to principal stress rotation:Experimental and numerical investigations
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作者 Huandui Liu Guibin Wang +2 位作者 Chunhe Yang Junyue Zhang Shiwan Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3544-3557,共14页
During the construction and operation of gas storage reservoirs,changes in the principal stress direction can induce fracture propagation under conditions of lower differential stress,potentially leading to failure in... During the construction and operation of gas storage reservoirs,changes in the principal stress direction can induce fracture propagation under conditions of lower differential stress,potentially leading to failure in the surrounding rock.However,the weakening of strength due to pure stress rotation has not yet been investigated.Based on fracture mechanics,an enhanced Mohr-Coulomb strength criterion considering stress rotation is proposed and verified with experimental and numerical simulations.The micro-damage state and the evolution of the rock under the pure stress-rotation condition are analyzed.The findings indicate that differential stress exceeding the crack initiation stress is a prerequisite for stress rotation to promote the development of rock damage.As the differential stress increases,stress rotation is more likely to induce rock damage,leading to a transition from brittle to plastic failure,characterized by wider fractures and a more complex fracture network.Overall,a negative exponential relationship exists between the stress rotation angle required for rock failure and the differential stress.The feasibility of applying the enhanced criterion to practical engineering is discussed using monitoring data obtained from a mine-by tunnel.This study introduces new concepts for understanding the damage evolution of the surrounding rock under complex stress paths and offers a new theoretical basis for predicting the damage of gas storage reservoirs. 展开更多
关键词 Principal stress rotation(PSR) Fracture mechanics Hollow cylinder torsional apparatus for rock (HCAR) Particle flow method Rock strength
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阿尔都塞意识形态概念的四重意蕴及其当代价值
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作者 张依林 《江苏科技大学学报(社会科学版)》 2024年第3期28-34,共7页
意识形态概念是阿尔都塞思想的一个核心概念,贯穿其思想发展过程始终。阿尔都塞的意识形态概念是在批判地继承马克思意识形态批判理论基础上,站在结构主义立场上,融合了无意识观点和镜像结构学说形成的。阿尔都塞主要从四个维度阐释了... 意识形态概念是阿尔都塞思想的一个核心概念,贯穿其思想发展过程始终。阿尔都塞的意识形态概念是在批判地继承马克思意识形态批判理论基础上,站在结构主义立场上,融合了无意识观点和镜像结构学说形成的。阿尔都塞主要从四个维度阐释了意识形态概念:一是从认识论维度阐释了作为表象体系的意识形态,二是从存在论维度阐释了作为物质实体的意识形态,三是从实践论维度阐释了作为资产阶级国家机器的意识形态,四是从功能论维度阐释了能够唤问个体为主体的意识形态。这四个维度的阐释既体现了阿尔都塞意识形态概念的丰富意蕴,也暴露了意识形态主体的空场或隐匿。 展开更多
关键词 阿尔都塞 表象体系 唤问功能 意识形态 国家机器
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