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Effect of Heat Treatment Process on Properties of 1000 MPa Ultra-High Strength Steel

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Journal of Iron and Steel Research International 2011年第2期18卷 64-69页

作者： YU Wei QIAN Ya-jun wu Hui-bin yang Yue-hui Metallurgical Engineering Institute University of Science and Technology Beijing Beijing 100083 China

Two types of steel, C-Mn-CrMo B microalloyed steel and C-Mn-Mo-Nb-Cu-B microalloyed steel, are designed to develop 1000 MPa ultra high strength steel. Two kinds of processes, thermomeehanical controlled process （TMCP） combined with traditional off-line quenching and tempering （QT） process versus controlled rolling process （CR） combined with direct quenching and tempering （DQ＋T） process, are applied. The effect of heat treatment processing mode on the microstructure and mechanical properties is studied. The relationship between microstructure and mechanical properties is investigated by SEM and TEM. After tempering at 450 to 550 ℃ for 1 h, the steel produced by TMCP＋QT process shows combination of excellent strength and low temperature toughness. The yield strength is above 1 000 MPa, elongation above 15% and impact energy at -40 ℃ more than 30 J. After tempering at 450 ℃, a large number of ε-Cu particles precipitated in C-Mn-Mo-Nb-Cu-B steel produced by CR＋DQ＋T process lead to a significant increase in yield strength. And after tempering at 500 to 600 ℃, the yield strength of the steel is further improved to 1 030 MPa because of precipitates, such as nitride or carbide of niobium, carbide of molybedenum and vanadium. When the tempering temperature is increased above 620 ℃, the yield strength is still higher than 1 000 MPa and elongation is above 20% and impact energy at --40 ℃ is more than 35 J. After tempering at above 500 ℃, the toughness of the steel treated by TMCP＋QT process is superior to that of steel by CR＋DQ＋T process.

关键词： heat treatment high strength steel microstructure mechanical property

Scavenging and release of REE and HFSE by Na-metasomatism in magmatic-hydrothermal systems

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Fundamental Research 2024年第2期4卷 315-323页

作者： wu-bin yang He-Cai Niu Ning-Bo Li Pete Hollings Shannon Zurevinski Roger H.Mitchell Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China Department of Geology Lakehead UniversityThunder BayON P7B 5E1Canada

Exploitable or potentially exploitable deposits of critical metals,such as rare-earth(REE)and high-field-strength elements(HFSE),are commonly associated with alkaline or peralkaline igneous ***,the origin,transport and concentration of these metals in peralkaline systems remains poorly *** study presents the results of a mineralogical and geochemical investigation of the Na-metasomatism of alkali amphiboles and clinopyroxenes from a barren peralkaline granite pluton in NE China,to assess the remobilization and redistribution of REE and HFSE during magmatic-hydrothermal *** amphiboles and aegirine-augites from the peralkaline granites show evolutionary trends from sodic-calcic to sodic compositions,with increasing REE and HFSE concentrations as a function of increasing Na-index[Na^(#),defined as molar Na/(Na+Ca)ratios].The Na-amphiboles(i.e.,arfvedsonite)and aegirine-augites can be subsequently altered,or breakdown,to form hydrothermal aegirine during late-or post-magmatic *** compositions analyzed by insitu LA-ICPMS show that the primary aegirine-augites have high and variable REE(2194-3627 ppm)and HFSE(4194-16,862 ppm)contents,suggesting that these critical metals can be scavenged by alkali amphiboles and *** to the primary aegirine-augites,the presentative early replacement aegirine(Aeg-I,Na^(#)=0.91-0.94)has notably lower REE(1484-1972)and HFSE(4351-5621)*** contrast,the late hydrothermal aegirine(Aeg-II,Na^(#)=0.92-0.96)has significantly lower REE(317-456 ppm)and HFSE(6.44-72.2 ppm)*** that the increasing Na^(#)from aegirine-augites to hydrothermal aegirines likely resulted from Na-metasomatism,a scavenging-release model can explain the remobilization of REE and HFSE in peralkaline granitic *** scavenging and release of REE and HFSE by Na-metasomatism provides key insights into the genesis of globally significant REE and HFSE *** high Na-index of th

关键词： Critical metals Alkali amphiboles Na-metasomatism REE and HFSE Na-index(Na^(#))

Mechanism of the protective effects of noninvasive limbs preconditioning on myocardial ischemia-reperfusion injury

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Chinese Medical Journal 2005年第20期118卷 1723-1727页

作者： CHEN Xiao-guang wu bin-yang WANG Jun-ke BAI Tao Department of Anesthesiology First Affiliated Hospital ChinaMedical University Shenyang 110001 China

Background This study aimed at assessing the effect of noninvasive limb preconditioning on myocardial infarct size, and determining whether nitric oxide and neurogenic pathway play an important role in the mechanism of acute remote ischemic preconditioning （IPC）.Methods Forty Wistar rats were randomly divided into four experimental groups. In Group I , the rats underwent 30-minute occlusion of the left anterior descending coronary artery, and 120-minute reperfusion. In Group PL, the rats underwent four cycles of 5-minute occlusion and reperfusion of both hind limbs using a tourniquet before the experiment was continued as in Group I. In Group PL-N and Group PL-,, we administered L-nitro-arginine methyl ester （L-NAME） 10 mg/kg or hexamethonium chloride 20 mg,/kg intravenously, 10 minutes before IPC. Infarct size as a percentage of the area at risk was determined by triphenyhetrazolium chloride staining.Results There were no statistically significant differences in mean arterial pressure and heart rate among these groups at any time point during the experiment （ P〉0. 05 ）. The myocardial infarct size （IS） was decreased significantly in Group PL and Group PL-U compared with Group I , and the IS/AAR was 34. 5%± 7.6%, 35.9%±8.6% and58.5%±8.5%, respectively （P〈0.05）. The IS/AAR was 49.1%±6.5% in Group PEN, and there was no significant difference compared with Group I （P〉0. 05 ）.Conclusions Noninvasive limb IPC is effective in protecting the myocardium from ischemia reperfusion injury. Nitric oxide plays an important role in the mechanism of acute remote IPC, in which the neurogenic pathway is not involved.

关键词： limb preconditioning ·ischemia-reperfusion injury myocardial protection· nitric oxide·neurogenic pathway

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微水对绝缘油凝点倾点影响的红外光谱检测

北京理工大学学报 2017年第2期37卷 185-190,195页

作者：陈彬武宏阳刘阁重庆工商大学废油资源化技术与装备教育部工程研究中心重庆400067

探讨微量水分影响机理以便采取有效措施监控绝缘油的运行状态.首先配制不同微水体积分数的绝缘油样,通过实验测试油样的凝点、倾点值;再对每组油样进行红外光谱扫描,得到油样中石蜡质成分(特征波数为722cm^(-1))、水分(特征波数为1 640,... 详细信息

探讨微量水分影响机理以便采取有效措施监控绝缘油的运行状态.首先配制不同微水体积分数的绝缘油样,通过实验测试油样的凝点、倾点值;再对每组油样进行红外光谱扫描,得到油样中石蜡质成分(特征波数为722cm^(-1))、水分(特征波数为1 640,3 400,3 450,3 615cm^(-1))的吸光度值;最后对每组油样中水分子在不同红外波数处的吸光度值、油样中石蜡质吸光度值、油样凝点倾点实验值之间进行皮尔逊相关系数分析,并建立了722,1 640,3 400,3 450,3 615cm^(-1)波数吸光度值与凝点倾点值的多元线性回归模型,模型的拟合优度分别为0.987 3和0.993 6,模型对油液凝点倾点的预测值与实测值之间的误差范围为0.033%~0.350%.结果表明微水对绝缘油凝点倾点的影响规律是随着油水分散系中水分体积分数增加,油液的凝点倾点值均呈现小幅增加趋势,水分对油样石蜡质成分吸光度值影响作用明显.

关键词：微量水分红外光谱绝缘油凝点倾点

A Study of the Development of the World Postal Parcel Service

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The Journal of China Universities of Posts and Telecommunications 2003年第3期10卷 107-112页

作者： ZHANG Hong fen, wu Hong bin, yang Wen xiu (Training Department of Shijiazhuang Postal College, Shijiazhuang 050021, P. R. China) Training Department of Shijiazhuang Postal College Shijiazhuang 050021

The paper makes an analysis of the market demands, market competition,collaboration and the current development of the postal parcel service, and discusses some factorscounteracting the development of the postal parcel service. Furthermore, this paper gives anorientation to the future development of the postal parcel service through a comprehensive researchon the developing trend of the postal parcel service in some countries.

关键词： the market of postal parcel service service structure individual service market orientation

Effects of different combustion modes on the thermal efficiency and emissions of a diesel pilot-ignited natural gas engine under low-medium loads

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Journal of Central South University 2022年第7期29卷 2213-2224页

作者： JIN Shou-ying LI Jin-ze ZI Zhen-yuan LIU Ya-long wu bin-yang State Key Laboratory of Engines Tianjin UniversityTianjin 300072China

Research on dual-fuel(DF)engines has become increasingly important as engine manufacturers seek to reduce carbon dioxide *** are significant advantages of using diesel pilot-ignited natural gas engines as DF ***,different combustion modes exist due to variations in the formation of the *** research used a simulation model and numerical simulations to explore the combustion characteristics of high-pressure direct injection(HPDI),partially premixed compression ignition(PPCI),and double pilot injection premixed compression ignition(DPPCI)combustion modes under a low-medium *** results revealed that the DPPCI combustion mode provides higher gross indicated thermal efficiency and more acceptable total hydrocarbon(THC)emission levels than the other *** to its relatively good performance,an experimental study was conducted on the DPPCI mode engine to evaluate the impact of the diesel dual-injection strategy on the combustion *** the DPPCI mode,a delay in the second pilot ignition injection time increased THC emissions(a maximum value of 4.27g/(kW·h)),decreased the emission of nitrogen oxides(a maximum value of 7.64 g/(kW·h)),increased and then subsequently decreased the gross indicated thermal efficiency values,which reached 50.4%under low-medium loads.

关键词： diesel pilot-ignited natural gas engine direct injection of natural gas combustion mode thermal efficiency emissions

Mechanism of the protective effects of noninvasive limbs preconditioning on myocardial ischemia-reperfusion injury

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中华医学杂志(英文版) 2005年第20期 53-57页

作者： CHEN Xiao-guang, wu bin-yang, WANG Jun-ke and BAI Tao Department of Anesthesiology, First Affiliated Hospital, China Medical Unive rsity, Shenyang 110001, China

Background This study aimed at assessing the effect of noninvasive limb preconditioning on myocardial infarct size, and deter mining whether nitric oxide and neurogenic pathway play an important role in the mechanism of acute remote ischemic preconditioning (IPC). Methods Forty Wistar rats were randomly divided into fo ur experimental groups. In Group Ⅰ, the rats underwent 30-minute occlusion of the left anterior descending coronary artery, and 120-minute reperfusion. In Group PL, the rats underwent four cycles of 5-minute occlusion and reperfusion of both h ind limbs using a tourniquet before the experiment was continued as in Group Ⅰ. In Group P L-N and Group P L-H, we administered L-nitro-arginine meth yl ester (L-NAME) 10 mg/kg or hexamethonium chloride 20 mg/kg intravenously, 10 minutes before IPC. Infarct size as a percentage of the area at risk was deter mine d by triphenyltetrazolium chloride staining. Results There were no statistically significant differences in mean arterial pressure and heart rate amo ng these groups at any time point during the experiment (P>0.05). The myo cardial infarct size (IS) was decreased significantly in Group PL and Group P  L-H compared with Group Ⅰ, and the IS/AAR was 34.5%±7.6%, 35.9%±8. 6 % and 58.5%±8.5%, respectively (P0.05). Conclusions Noninvasive limb IPC is effective in protecting the myocardium from ischemia reperfusion injury. Nitric oxide plays an important r ole in the mechanism of acute remote IPC, in which the neurogenic pathway is not involved .

关键词： limb preconditioning · ischemia-reperfusion injury · myocardial protection · nitric oxide · neurogenic pathway

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凝血IX因子复合物的研制

华西药学杂志 2000年第3期15卷 177-179页

作者：邬杨斌余蓉中国医学科学院中国协和医科大学输血研究所四川成都610081 华西医科大学药学院四川成都610044

目的 :提高IX因子复合物的活性收率和IX因子复合物的血栓安全性。方法 :采用国产DEAE sepharosefastflow胶离子交换层析及Ca3(PO4 ) 2 吸附法 ,从新鲜冰冻血浆中直接制备凝血Ⅸ因子复合物。结果 :二步的收率分别为 ( 76 42± 4 48) %和... 详细信息

目的 :提高IX因子复合物的活性收率和IX因子复合物的血栓安全性。方法 :采用国产DEAE sepharosefastflow胶离子交换层析及Ca3(PO4 ) 2 吸附法 ,从新鲜冰冻血浆中直接制备凝血Ⅸ因子复合物。结果 :二步的收率分别为 ( 76 42± 4 48) %和 ( 74 31± 3 17) % ,制品的FⅨ :C的比活比传统Ⅸ因子复合物提高了约 2 0倍。结论

关键词：凝血IX因子复合物离子交换层析法

Ammonia pyrolysis oxidation excited by nanosecond pulsed discharge:Global/fluid models hybrid solution

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Journal of Energy Chemistry 2025年第1期100卷 385-396页

作者： Mingming Zhang Hanyu wu Qi Chen Jiaxin yang Bonan Liu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University China University of Petroleum

The kinetic characteristics of plasma-assisted oxidative pyrolysis of ammonia are studied by using the global/fluid models hybrid solution ***,the stable products of plasma-assisted oxidative pyrolysis of ammonia are *** results show that the consumption of NH3/O2and the production of N2/H2change linearly with the increase of voltage,which indicates the decoupling of nonequilibrium molecular excitation and oxidative pyrolysis of ammonia at low ***,the detailed reaction kinetics mechanism of ammonia oxidative pyrolysis stimulated by a nanosecond pulse voltage at low pressure and room temperature is *** on the reaction path analysis,the simplified mechanism is *** detailed and simplified mechanism simulation results are compared with experimental data to verify the accuracy of the simplified ***,based on the simplified mechanism,the fluid model of ammonia oxidative pyrolysis stimulated by the nanosecond pulse plasma is established to study the pre-sheath/sheath behavior and the resultant consumption and formation of key *** results show that the generation,development,and propagation of the pre-sheath have a great influence on the formation and consumption of *** consumption of NH3by the cathode pre-sheath is greater than that by the anode pre-sheath,but the opposite is true for OH and O（1S）.However,within the sheath,almost all reactions do not ***,by changing the parameters of nanosecond pulse power supply voltage,it is found that the electron number density,electron current density,and applied peak voltages are not the direct reasons for the structural changes of the sheath and ***,the discharge interval has little effect on the sheath structure and gas mixture *** research results of this paper not only help to understand the kinetic promotion of non-equilibrium excitation in the process of oxidative pyrolysis but also help to explore th

关键词： Nanosecond pulsed discharge Ammonia Oxidative pyrolysis Fluid model Global model