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用分子轨道稳定化能曲面研究d^8低自旋配合物的几何构型
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作者 焦庆祝 王玉宝 +1 位作者 董兆鹏 刘梅 《烟台师范学院学报(自然科学版)》 1999年第3期199-202,共4页
用自编程序计算了d8 低自旋配合物中心离子的d 电子在不同d 轨道中分布时,配体在不同空间方向上与中心离子配位所产生的分子轨道稳定化能,并绘制了分子轨道稳定化能曲面图,由此阐明了该类配合物的配位数、几何构型。
关键词 分子轨道 中心离子 MOSE 配合物 几何构型
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通过分子轨道稳定化能曲面研究d^8低自旋配合物的几何构型
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作者 汪颖军 吴殿义 王佳 《高师理科学刊》 2001年第2期37-39,共3页
自编程序计算了d8低自旋配合物中心离子不同d电子分布时配体在不同空间方向上与中心离子配位所产生的分子轨道稳定化能 ,并首次绘制了分子轨道稳定化能曲面 ,由此阐明了该类配合物的配位数、几何构型。
关键词 分子轨道稳定化能 d^8低自旋配合物 几何构型 空间曲面
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Associations of oxidative stress and inflammation and their role in the regulation of membrane fluidity of red blood cells in hypertensive and normotensive men: An electron spin resonance investigation 被引量:1
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作者 Kazushi Tsuda 《Advances in Bioscience and Biotechnology》 2012年第7期1020-1027,共8页
There is evidence showing that increased levels of oxidative stress and C-reactive protein (CRP) might be associated with obesity, hypertension, atherosclerosis and other cardiovascular diseases. This study was undert... There is evidence showing that increased levels of oxidative stress and C-reactive protein (CRP) might be associated with obesity, hypertension, atherosclerosis and other cardiovascular diseases. This study was undertaken to investigate possible relationships among plasma 8-iso-prostaglandin F2α (8-iso-PG F2α: an index of oxidative stress), high-sensitivity (hs)-CRP and membrane fluidity (a reciprocal value of microviscosity) in hypertensive and normotensive men using an electron spin resonance (ESR)-method. The order parameter (S) for the spin-label agents (5-nitroxide stearate) of red blood cell (RBC) membranes in the ESR spectra was significantly higher in hypertensive men than in normotensive men, indicating that membrane fluidity was decreased in hypertensive men. Both plasma 8-iso-PG F2α and hs-CRP levels were significantly increased in hypertensive men compared with normotensive men. In addition, plasma plasma 8-iso-PG F2α levels were correlated with plasma hs-CRP levels. In contrast, plasma nitric oxide (NO)-metabolites were lower in hypertensive men than in normotensive men, and inversely correlated with plasma 8-iso-PG F2α and hs-CRP. The order parameter(S) of RBCs was correlated with plasma 8-iso-PG F2α and plasma hs-CRP, and inversely correlated with plasma NO-metabolites, suggesting that reduced membrane fluidity of RBCs might be associated with increased oxidative stress, inflammation and endothelial dysfunction. Multivariate regression analysis also showed that, after adjusting for general risk factors, both plasma 8-iso-PG F2α and hs-CRP were significant determinants of membrane fluidity of RBCs. The ESR suggests that associations of oxidative stress and inflammation might have a close correlation with impaired rheologic behavior of RBCs and microcirculatory dysfunction in hypertensive men. 展开更多
关键词 Oxidative Stress 8-Iso-Prostaglandin F2Α High-Sensitivity C-Reactive Protein NITRIC Oxide Membrane FLUIDITY Electron spin Resonance Hypertension
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二维磁性半导体笼目晶格Nb_(3)Cl_(8)单层的磁性及自旋电子输运性质
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作者 樊晓筝 李怡莲 +3 位作者 吴怡 陈俊彩 徐国亮 安义鹏 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第24期107-114,共8页
具有本征磁性的二维半导体材料在实现低功耗、小尺寸和高效率的自旋电子学器件方面具有重要应用前景.一些拥有特殊晶格结构的二维材料,如笼目晶格结构,凭借其在磁性和电学方面的新颖性质而受到研究者的青睐.最近,一种新的具有笼目晶格... 具有本征磁性的二维半导体材料在实现低功耗、小尺寸和高效率的自旋电子学器件方面具有重要应用前景.一些拥有特殊晶格结构的二维材料,如笼目晶格结构,凭借其在磁性和电学方面的新颖性质而受到研究者的青睐.最近,一种新的具有笼目晶格结构的二维磁性半导体材料Nb_(3)Cl_(8)单层被成功制备出来,为探索具有笼目结构的二维磁性半导体器件提供了新机会.本文通过第一性原理方法研究了Nb_(3)Cl_(8)单层的电子结构、磁各向异性,构造了其p-n结二极管结构,并研究了其自旋输运性质.结果表明,Nb_(3)Cl_(8)单层易磁化轴在平面内,沿x轴方向,Nb原子对磁各向异性起主要贡献,且相关磁性可通过应力应变进行调控.此外,基于Nb_(3)Cl_(8)单层的p-n结二极管纳米器件表现出整流效应、自旋过滤效应以及负微分电阻现象.这些结果表明了Nb_(3)Cl_(8)单层在下一代高性能自旋电子器件方面具有较大的应用潜力. 展开更多
关键词 Nb_(3)Cl_(8)单层 磁性材料 磁各向异性 自旋电子输运
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Hyperhomocysteinemia and Increased Oxidative Stress Levels Are Associated with Impaired Membrane Fluidity of Red Blood Cells in Hypertensive and Normotensive Men: An Electron Spin Resonance Investigation
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作者 Kazushi Tsuda 《International Journal of Clinical Medicine》 2013年第1期58-65,共8页
Hyperhomocysteinemia and oxidative stress may be strongly linked to hypertension, atherosclerosis and other cardiovascular diseases. The present study was performed to investigate possible relationships among plasma t... Hyperhomocysteinemia and oxidative stress may be strongly linked to hypertension, atherosclerosis and other cardiovascular diseases. The present study was performed to investigate possible relationships among plasma total homocysteine, plasma 8-iso-prostaglandin F2α (8-isoPG F2α: an index of oxidative stress), and membrane fluidity (a reciprocal value of membrane microviscosity) in hypertension. We measured the membrane fluidity of red blood cells (RBCs) in hypertensive and normotensive men using an electron spin resonance (ESR) and spin-labeling method. Membrane fluidity of RBCs was significantly decreased in hypertensive men compared with normotensive men. Plasma total homocysteine levels were significantly higher in hypertensive men than in normotensive men, and correlated with plasma 8-isoPG F2α. In contrast, plasma nitric oxide (NO)-metabolites (an index of endothelial function) were lower in hypertensive men than in normotensive men. The reduced membrane fluidity of RBCs was associated with increased total homocysteine and plasma 8-isoPG F2α levels and decreased plasma NO-metabolite levels. Multivariate regression analysis showed that, after adjusting for general risk factors, plasma total homocysteine and 8-isoPG F2α were significant determinants of membrane fluidity of RBCs, respectively. These results suggest that hyperhomocysteinemia and oxidative stress with endothelial dysfunction might have a close correlation with impaired rheologic behavior of RBCs and circulatory disorders in hypertensive men. 展开更多
关键词 HOMOCYSTEINE Oxidative Stress 8-Iso-Prostaglandin F2Α Nitric Oxide Membrane FLUIDITY Red Blood Cell Electron spin Resonance Hypertension
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涤纶FDY8头改16头纺丝及工艺探讨
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作者 赵联营 《化纤与纺织技术》 2005年第1期1-3,12,共4页
探讨了东丽716型高速卷绕机8头纺FDY生产线改造为16头纺的设备改造和工艺调整.通过调整组件的密封垫厚度,使旋转紧固的纺丝组件固定在易于分丝的同一位置.通过适当提高丝束在GR2出口处的张力, 避免丝束抖动碰撞及并丝.纸管的合理设计及... 探讨了东丽716型高速卷绕机8头纺FDY生产线改造为16头纺的设备改造和工艺调整.通过调整组件的密封垫厚度,使旋转紧固的纺丝组件固定在易于分丝的同一位置.通过适当提高丝束在GR2出口处的张力, 避免丝束抖动碰撞及并丝.纸管的合理设计及切换时卷绕张力的适当提高, 保证了切换的成功率.为了确保丝饼成形良好, 卷绕角设定为4~5°、卷绕张力小于13cN是比较合适的. 展开更多
关键词 涤纶FDY 工艺探讨 卷绕张力 生产线改造 高速卷绕机 工艺调整 设备改造 16头纺 纺丝组件 合理设计 密封垫 卷绕角 丝束 切换 东丽 并丝
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红花水提物不同有效部位的体外抗辐射作用及机制研究 被引量:1
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作者 范莉 刘建香 +3 位作者 封江彬 姜晓燕 高刚 田梅 《癌变.畸变.突变》 CAS CSCD 2017年第2期125-128,133,共5页
目的:通过对红花水提物中不同有效部位进行抗辐射效应及作用机制的初步探讨,为开发新型安全有效的辐射防护药物提供实验依据。方法:红花药材用蒸馏水60℃提取得红花水提物,采用大孔树脂HP-20洗脱分离得到水部位和30%、50%、70%、95%醇部... 目的:通过对红花水提物中不同有效部位进行抗辐射效应及作用机制的初步探讨,为开发新型安全有效的辐射防护药物提供实验依据。方法:红花药材用蒸馏水60℃提取得红花水提物,采用大孔树脂HP-20洗脱分离得到水部位和30%、50%、70%、95%醇部位,采用电子自旋共振波谱仪(ESR)检测红花水提物不同有效部位清除自由基的能力;经红花水提物30%及5%醇部位处理后,利用CCK-8法检测其对^(60)Co γ射线照射后人肝L02细胞存活率的影响;流式细胞术研究其对^(60)Co γ射线照射后人淋巴细胞AHH-1细胞凋亡、细胞周期及Bcl-2/Bax比率的影响。结果:ESR自由基清除实验显示红花水提物的不同有效部位均具有清除自由基能力,半数抑制浓度IC 50值为1.7~79.7 mg/m L。CCK-8法检测结果显示30%及50%醇部位处理辐照后L02细胞的存活率分别为128.3%及130.9%,与照射组比较显著增加(P<0.01)。流式细胞术结果显示与照射组凋亡率(24.7%±4.4%)比较,红花水提物30%及50%醇部位处理组凋亡率分别为15.3%±1.6%及15.2%±1.9%,明显降低(P<0.01)。细胞周期实验结果显示与照射组AHH-1细胞G2/M期比例(45.7%±0.7%)比较,红花水提物30%及50%醇部位处理组G2/M期细胞比例分别为(42.3%±0.6%)及(36.4%±0.4%),差异有统计学意义(P<0.01),同时红花水提物30%及50%醇部位能缓解照射引起的Bcl-2/Bax比率下降(P<0.05)。结论:红花水提物的30%及50%醇洗脱部位对^(60)Co γ射线照射的L02、AHH-1细胞具有明显的辐射防护作用,其作用机制可能与清除自由基、改善细胞周期G2/M期阻滞、调控Bcl-2/Bax比率进而抑制细胞凋亡有关,可作为潜在的安全有效的抗辐射药物继续研究。 展开更多
关键词 红花 有效部位 电子自旋共振波谱仪 CCK-8 作用机制
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喷气涡流纺喷孔数量对喷嘴内气流场的影响 被引量:3
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作者 陈彩红 陈洪立 《轻工机械》 CAS 2017年第1期64-66,共3页
为了研究喷孔数量对喷嘴内气流场的影响,应用FLUENT流体计算软件对喷嘴内部气流场进行数值模拟,并结合Origin Pro 8对不同喷孔数量时喷嘴内部气流场状况进行比较和分析,深入解析喷孔数量对涡流场的影响。研究表明:喷孔数量对喷嘴内部气... 为了研究喷孔数量对喷嘴内气流场的影响,应用FLUENT流体计算软件对喷嘴内部气流场进行数值模拟,并结合Origin Pro 8对不同喷孔数量时喷嘴内部气流场状况进行比较和分析,深入解析喷孔数量对涡流场的影响。研究表明:喷孔数量对喷嘴内部气流场的特性影响较为明显,随着喷孔数量的增多,气流在喷嘴中形成的旋转运动增强,喷嘴入口处用以吸引纤维的负压也随之增大,对纱线的加捻特性也就越强。 展开更多
关键词 喷气涡流纺 气流场 喷孔数量 FLUENT流体计算软件 OriginPro 8软件
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浅谈转杯纺在新疆的发展优势 被引量:1
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作者 黄克华 《棉纺织技术》 CAS 北大核心 2017年第7期81-84,共4页
探讨了在新疆发展转杯纺纱项目的优势,以及纺专器材的优选。从产量、设备配台数、用工、投资额、筒纱容量、加工费和利润等方面,将转杯纺纱与环锭纺纱进行对比,总结了在新疆投资转杯纺项目的优势。以Autocoro 8型转杯纺纱机为例,分析了... 探讨了在新疆发展转杯纺纱项目的优势,以及纺专器材的优选。从产量、设备配台数、用工、投资额、筒纱容量、加工费和利润等方面,将转杯纺纱与环锭纺纱进行对比,总结了在新疆投资转杯纺项目的优势。以Autocoro 8型转杯纺纱机为例,分析了各种型号的转杯凝聚槽、表面处理形式的优缺点以及适纺类型,介绍了各种分梳辊针齿型号、表面处理形式以及假捻器型号对纱线质量的影响。认为:在新疆的政策扶持下,采用转杯纺生产中粗号纱的优势明显;掌握各种型号纺专器材的优缺点,有利于充分发挥转杯纺的优势。 展开更多
关键词 AUTOCORO 8型转杯纺纱机 ZINSER 351型细纱机 凝聚槽 分梳辊 假捻器
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Nonclassical Plane-crystallographic Groups and Their Applications IV
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作者 Lequan Min Xaodan zhang(Applied Science School, School,University of Science and Technology Beijing, Beijing 100083,China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1998年第4期228-232,共5页
Eight kinds of nonclasslcal periodic lattices with locally 8-fold rotational symmetries are introduced.They can be described via nonclassical Planc-crystallographic groups. The periodic lattices may be interpreted byt... Eight kinds of nonclasslcal periodic lattices with locally 8-fold rotational symmetries are introduced.They can be described via nonclassical Planc-crystallographic groups. The periodic lattices may be interpreted bythe projections on the plane of the corresponding unit cells consisting of embedding polyhedrons, respectively. TheFourier-transform patterns of the Periodic lattices have striking approximate'8-fold rotational symmetries', some ofwhich are similar to those displaying in the electrton-diffraction patterns of so-called quasicrystals. 展开更多
关键词 nonclasslcal crystallographic groups locoally 8-fold symmetry Fourier-transform patterns quasicrystals
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9×19S+PWRC电梯用钢丝绳的研发及使用 被引量:3
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作者 过惠成 《金属制品》 2011年第1期22-25,共4页
阐述电梯用钢丝绳的发展概况,8×19S+FC作为电梯用钢丝绳的主要结构,适用于楼层较低和速度较慢的电梯;9×19类平行捻结构的钢芯钢丝绳柔软性好,金属填充率高,破断拉力高,结构伸长率低,抗疲劳性能好,适用于高层建筑中的高速电梯... 阐述电梯用钢丝绳的发展概况,8×19S+FC作为电梯用钢丝绳的主要结构,适用于楼层较低和速度较慢的电梯;9×19类平行捻结构的钢芯钢丝绳柔软性好,金属填充率高,破断拉力高,结构伸长率低,抗疲劳性能好,适用于高层建筑中的高速电梯用钢丝绳。介绍捻距倍数为7的1570 MPa级9×19S+PWRC—10结构规格钢丝绳的主要技术参数及配丝计算过程,钢丝绳最小破断拉力66.0 kN,结构伸长率不大于1.5%,右交互捻,捻距67.9~72.1 mm;股捻距倍数:外层股为8.5,内层股为8.5,中心股为7。针对该结构钢丝绳结构特点,提出制造、安装和使用维护的注意事项。 展开更多
关键词 8×19S+FC钢丝绳 9×19类平行捻钢丝绳 结构设计 配丝 捻制 钢丝绳安装使用
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The Principles of Causal Conspiracy
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作者 Michael M.Anthony 《Journal of Quantum Information Science》 2014年第3期137-172,共36页
The human mind understands logical processes and causality and formulates theories based on logical descriptions of empirical evidence. The Principles of Causal Conspiracy is based on defining information as logical c... The human mind understands logical processes and causality and formulates theories based on logical descriptions of empirical evidence. The Principles of Causal Conspiracy is based on defining information as logical charges similar to electric charges. Such information charges can be modeled in the vacuum of a quantum probability firmament as symmetry of quantum charges with a zero net charge. Observation of a state lifts one of these charges in a M&oumlbius transformation from a multipolar field of possibilities that maximizes a local monopole field that is observable. In the first of several papers, I introduce new and profound principles, the Principles of Causal Conspiracy, to provide a consistent epistemology for quantum theory, relativity theory and all the known sciences. 展开更多
关键词 Special Relativity Theory Dipole MONOPOLES Quantum Theory QUARKS Space Time Moments Big Bang MOND ANNIHILATORS Creators Fields Charges Logic MOBIUS Lagrangian Blackholes Riemann Sphere Causality Uncertainty Blackbody Radiation 8-fold Way
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Charmed baryon resonances with heavy-quark symmetry
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作者 L. Tolos C. Garcia-Recio +4 位作者 V. K. Magas T. Mizutani J. Nieves A. Ramos L. L. Salcedo 《Chinese Physics C》 SCIE CAS CSCD 2009年第12期1323-1326,共4页
We study charmed baryon resonances that are generated dynamically from a coupled-channel unitary approach that implements heavy-quark symmetry. Some states can already be identified with experimental observations, suc... We study charmed baryon resonances that are generated dynamically from a coupled-channel unitary approach that implements heavy-quark symmetry. Some states can already be identified with experimental observations, such as Ac(2595), Ac(2660), Ec(2902) or Ac(2941), while others need a compilation of more experimental data as well as an extension of the model to include higher order contributions. We also compare our model to previous SU(4) schemes. 展开更多
关键词 charmed baryon resonances heavy-quark symmetry SU(8 and SU(4) spin-flavor symmetry
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