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扫描床用直流伺服电动机的驱动方式

微电机 2003年第2期36卷 36-38页

作者：郭宏宋涛北京航空航天大学自动化科学与电气工程学院北京100083

利用 ANSOFT公司的仿真软件 SIMPL ORER 5 .0 ,对一种 CT扫描床用直流伺服电动机在不同驱动方式下的转速波动、阶跃响应和频率响应特性进行了仿真和对比分析。确定了适合于

关键词：直流伺服电动机驱动方式 CT扫描床 CT机医疗设备

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： song He Li Li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第01期 369-376页

作者： song-Meng Wang Hao Nian Yan-Fang Wang Li-Shuo Zheng Yu-tao Zheng Yi-Wei Dong Liping Huang Xiaoping Wang Wei Jiang Liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

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Subtoxicdose of chlorpyrifos down regulates ABCA1 expression and accelerates formation of atherosclerosis induced by the high fat diet in New Zealand rabbits

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Subtoxicdose of chlorpyrifos down regulates ABCA1 expression...

siRNA对γδT细胞Eomes基因表达的抑制功能研究

中国生理学会第23届全国会员代表大会暨生理学学术大会

作者： Shou-hong ZHOU~(1,2),Xu-hong YANG~2,tao song~2,Shu-Jin WU~2,Ning-Jiang HUANG~2,Li-Ying LIU~2 1 Department of Physiology,School of Medicine,University of South China,Hengyang,421001 China 2Dpartment of Pharmacology, School of Pharmaceutical Science,Central South University,Changsha 410078,China

＜正＞In order to explore the effect of exposure to subtoxic dose of organophosphorus insecticide chlorpyrifos on the formation of atherosclerosis induced by the high fat diet in New Zealand rabbits and analyze the possible mechanisms,thirty two healthy male New Zealand rabbits were divided randomly into four groups:control,high-fat diet,chlorpyrifos and high-fat diet + chlorpyrifos *** dose of chlorpyrifos（20 mg/kg per day） was administered by lavage every day for six *** levels of serum fat,activities of cholinesterase and alanine aminotransferase,serum creatinine and blood urea nitrogen were measured *** peritoneal macroph- ages were assembled and cellular cholesterol efflux was *** of atherosclerosis plaque of thoracic aorta was measured by SudanⅣ.Common carotid artery was fixed in formalin,sliced and HE dyed and pathology analysis system was *** expression of ABCA1 was detected by Real-time PCR and Western *** with control group,serum TC,LDL and TG were significantly increased and expressions of ABC A1 in liver,aorta and peritoneal macrophages were markedly increased and cholesterol efflux of peritoneal macrophages was significantly increased in high-fat diet *** was obvious atherosclerosis lesion in thoracic aorta and common carotid artery in high-fat diet *** with control group,activity of cholinesterase was significantly decreased,but there were no symptom of intoxation and injury of function of liver and kidney,and level of HDL, expression of ABCA1 and cholesterol efflux were markedly decreased in chlorpyrifos *** with high-fat diet group,activity of cholinesterase was decreased,but there were no symptom of intoxation and injury of function of liver and kidney,and expression of ABC A1 and cholesterol efflux were significantly decreased,the atherosclerosis lesion areas in thoracic aorta and common carotid artery were increased in high-fat diet + chlorpyrifos *** result

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现代免疫学 2010年第1期30卷 51-55页

作者：汪洪涛葛晓松李柏青蚌埠医学院免疫学教研室安徽省感染与免疫重点实验室蚌埠233030

本文旨在探讨RNA干扰对人外周血γδT细胞Eomes基因的表达和产生IFN-γ的抑制效应。化学合成3对EomessiRNA,脂质体转染试剂介导siRNA转染到用结核杆菌(Mtb)抗原刺激的人外周血单个核细胞中(主要是γδT细胞),通过转染条件优化后,对转染... 详细信息

本文旨在探讨RNA干扰对人外周血γδT细胞Eomes基因的表达和产生IFN-γ的抑制效应。化学合成3对EomessiRNA,脂质体转染试剂介导siRNA转染到用结核杆菌(Mtb)抗原刺激的人外周血单个核细胞中(主要是γδT细胞),通过转染条件优化后,对转染了siRNA的γδT细胞采用流式细胞术(FCM)进行分选,利用RT-PCR检测转染细胞EomesmRNA表达抑制率,以FCM检测转染前后γδT细胞IFN-γ产生的情况。结果显示,有2对siRNA能有效抑制Eomes的mRNA表达,并对γδT细胞IFN-γ的产生起抑制作用。提示Eomes siRNA可特异地抑制γδT细胞Eomes基因表达,Eomes可能是调控γδT细胞产生IFN-γ的重要转录因子。

关键词： siRNA γδT细胞 Eomes基因

Analysis of the second-order BDF scheme with variable steps for the molecular beam epitaxial model without slope selection

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Science China Mathematics 2021年第5期64卷 887-902页

作者： hong-Lin Liao Xuehua song tao Tang tao Zhou Department of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211101China Department of Mathematics and International Center for Mathematics Southern University of Science and TechnologyShenzhen 518055China Division of Science and Technology BNU-HKBU United International CollegeZhuhai 519087China NCMIS&LSEC Institute of Computational Mathematics and Scientific Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

In this work,we are concerned with the stability and convergence analysis of the second-order backward difference formula(BDF2)with variable steps for the molecular beam epitaxial model without slope *** first show that the variable-step BDF2 scheme is convex and uniquely solvable under a weak time-step *** we show that it preserves an energy dissipation law if the adjacent time-step ratios satisfy r_(k):=τ_(k)/τ_(k-1)<***,with a novel discrete orthogonal convolution kernels argument and some new estimates on the corresponding positive definite quadratic forms,the L^(2)norm stability and rigorous error estimates are established,under the same step-ratio constraint that ensures the energy stability,i.e.,0

关键词： molecular beam epitaxial growth variable-step BDF2 scheme discrete orthogonal convolution kernels energy stability convergence analysis

Joining mechanism of Mg alloy/steel butt joints with Cu-Zn interlayer by hybrid laser-TIG welding source

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Journal of Iron and Steel Research International 2018年第2期25卷 221-227页

作者： Gang song hong-yang Wang tao-tao Li Li-ming Liu Key Laboratory of Liaoning Advanced Welding and JoiningTechnology School of Materials Science and EngineeringDalian University of Technology Dalian 116024 LiaoningChina

Hybrid laser-TIG （tungsten inert gas） welding technology was used to join the Mg to steel with Cu-Zn interlayer. The effect of Al content in Mg alloy on the interface bonding of AZ31BMg/Q235 steel dissimilar butt joints was investigated. For comparison, ZK60 Mg alloy with no Al addition and AZ31 Mg alloy were utilized. The results showed that AZ31/Q235 butt joints with Cu-Zn interlayer, of which the fractures occurred in the Mg weld seam, showed quite sound and reliable interface bonding. The obvious concentration of element Al occurred along the Mg/steel interface. The results indicated that the addition of Cu-Zn interlayer, especially Zn, could significantly decrease the reaction temperature of Fe-Al at the Mg/ steel interface and promote the formation of reaction layer along the interface. The diffusion of Al element on the Mg-Fe interface was increased by the Cu-Zn interlayer. For ZK60 Mg alloy, Mg and Zn approaching the Mg-Fe interface were evaporated. The intense vaporizing could inhibit the direct contact between steel and Mg weld pool, even destroying the possible formation of reaction layer. The intimate interface bonding of AZ31/Q235 butt joints was attributed to the synergistic effect of element AI and Cu.

关键词： Hybrid laser-TIG welding Cu-Zn interlayer Aluminum Magnesium Steel

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深海龙抗运动性疲劳作用的效果观察

体育学刊 1996年第1期3卷 36-37,126-127+32页

作者：洪涛胡景斌宋爱军青岛海洋大学体育系 266003 青岛市体校

深海龙是由多种具有抗疲劳作用的强壮性中药成分配制而成的复方中成药.为了探索深海龙的抗运动性疲劳作用和对体能恢复作用的效果,本文对40名青少年(20名实验组、20名对照组)进行了一个月的大强度训练和药物效果观察.实验结果显示:经过... 详细信息

深海龙是由多种具有抗疲劳作用的强壮性中药成分配制而成的复方中成药.为了探索深海龙的抗运动性疲劳作用和对体能恢复作用的效果,本文对40名青少年(20名实验组、20名对照组)进行了一个月的大强度训练和药物效果观察.实验结果显示:经过服药训练,实验组递增负荷运动的最大工作时间和最大工作负荷量比服药训练前有明显提高,且明显高于对照组.定量负荷工作和最大负荷工作时的心率和血乳酸指标也显示服药训练使实验组的训练程度明显高于对照组.本研究结果提示,深海龙对人体长时间大强度工作能力有促进作用,可以加快大强度工作后体能的恢复,有较强的抗疲劳作用,因此,是一种理想的运动强壮型保健药物.

关键词：深海龙中成药抗运动性疲劳

Kinetics and mechanism of coal-based direct reduction of highchromium vanadium-titanium magnetite

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Journal of Iron and Steel Research International 2022年第11期29卷 1723-1733页

作者： Jian Yang tao Jiang Shi-hong Ma song-tao Yang Mi Zhou School of Information Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina

High-chromium vanadium-titanium magnetite(HCVTM)is a valuable resource containing metal elements such as iron,vanadium,titanium,and *** recycle these elements,direct reduction is an efficient *** mechanism and reaction kinetic parameters for the direct reduction of HCVTM were *** results show that the reduction degree increases obviously when the C/O ratio and temperature *** analysis showed a dramatic mass loss in the direct reduction of HCVTM in the temperature range of 985-1160℃.From 1200 to 1350℃,the reduction curves for the isothermal reduction of HCVTM followed the same trend,with a sharp increase in the initial reaction zone and a slight increase in the reduction rate with increasing time,and finally,the isothermal reduction process of HCVTM was divided into several limiting stages with varying degrees,with inconsistent limiting factors for the reaction rate at different *** results also show that the activation energy decreases slightly at larger degrees of ***,the apparent rate constant k(T)increased with increasing reduction temperature,with lnk(T)showing a good linear relationship with temperature.

关键词： High-chromium vanadium-titanium magnetite Direct reduction Reduction rate Kinetic Thermodynamic Analysis