检索结果-南通市图书馆

Effect of Nb Solute and NbC Precipitates on Dynamic or Static Recrystallization in Nb Steels

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2012年第11期19卷 52-56页

作者： xiao fu-ren CAO Ya-bin QIAO Gui-ying ZHANG xiao-bing LIAO Bo Key Laboratory of Metastable Materials Science and Technology College of Materials Science and EngineeringYanshan UniversityQinhuangdao 066004HebeiChina School of Environmental and Chemical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina Jiangsu Shagang Group Co Ltd Zhangjiagang215625JiangsuChina

Nb is often considered to be a powerful alloying element for controlling the recrystaUization process in mi- croalloyed high strength steels. However, Nb can be presented either as solute in solution, where it is thought to ex- hibit a strong solute drag effect, or as NbC precipitates, which are thought to be effective at pinning grain bounda- ries. Therefore, it is very important to quantitatively measure Nb in solution or in NbC precipitates. A quantitative analysis method of Nb in solution and in precipitates was proposed. The test procedure involved chemical dissolution, filtration and inductively coupled plasma atomic emission spectroscopic （ICP-AES） analysis. The amount of Nb in solution in Nb-microallyed steels under different treatment conditions was evaluated. The results show that the niobium and carbon contents in steels have a great effect on niobium dissolution kinetics. The solute Nb is more effective to retard dynamic recrystallization, while the NbC precipitates are more effective to inhibit static recrystaltization. The results may help to comprehend effect of Nb in steels, and provide some guides in the design of new high strength Nb-bearing steels.

关键词： Nh microalloyed steel solution precipitation quantitative analysis recrystallization

在线全文

学校读者我要写书评

暂无评论

针状铁素体管线钢组织及强韧化机理研究

材料热处理学报 2009年第2期30卷 57-62页

作者：廖波肖福仁燕山大学材料科学与工程学院河北秦皇岛066004

采用TEM及原位TEM拉伸裂纹扩展观察等试验手段,研究了管线钢针状铁素体组织及各组织单元对位错运动及裂纹扩展的影响,分析讨论了针状铁素体的强韧化机理。结果表明,大角度晶界、M/A组元对位错的运动及裂纹扩展有显著影响,有效阻碍位错... 详细信息

采用TEM及原位TEM拉伸裂纹扩展观察等试验手段,研究了管线钢针状铁素体组织及各组织单元对位错运动及裂纹扩展的影响,分析讨论了针状铁素体的强韧化机理。结果表明,大角度晶界、M/A组元对位错的运动及裂纹扩展有显著影响,有效阻碍位错的运动和裂纹扩展,从而提高材料强韧性。小角度晶界对位错运动影响较小,对裂纹扩展几乎没有影响。针状铁素体组织中以块状转变机制形成的块状铁素体和非等轴铁素体使管线钢具有高的韧性,而低温转变的板条状贝氏体组织对强度贡献更大。

关键词：管线钢针状铁索体原位TEM 裂纹扩展

A new method for evaluating wedges of steel plates and strips

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第7期31卷 1719-1735页

作者： xiao-bao Ma xiao-xin Ma Tao Wang Zhong-kai ren Yu-cheng ren College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Ministry of Education Engineering Research Center of Advanced Metal Composite Forming Technology and Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina China National Heavy Machinery Research Institute Co. Ltd.Xi'an 710018ShaanxiChina Faculty of Mechanical Engineering Hebei University of ArchitectureZhangjiakou 075000HebeiChina

To overcome the inaccuracy problem of the traditional wedge evaluation of steel plates and strips caused by the ran-domness of the thicknesses of two local points and improve the reliability of the wedge index,the double-centroid method for the wedge evaluation was proposed,and a model based on the centroid theory was ***,an integral model for the discrete thickness values of the cross-section profiles was *** discussion focused on the distinct characteristics of the two-point method,asymmetric method,and double-centroid method in evaluating the asymmetric distribution of *** three methods were employed to evaluate the wedge values of both the theoretical and measured cross-sections of steel plates and strips,and the accuracies of three wedge evaluation models were analyzed and *** results showed that the double-centroid method objectively reflects the degree and variation characteristics of the wedge values of the cross-sections of steel plates and strips,and this method is feasible,reliable,and outstanding.

关键词： Steel plate and strip Wedge Two-point method Double-centroid method Reliability

纳米晶Co_(78)Ni_(22)合金热稳定性

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

材料热处理学报 2014年第8期35卷 12-17页

作者：乔桂英荆天辅肖福仁燕山大学环境与化学工程学院河北省应用化学重点实验室河北秦皇岛066004 燕山大学材料科学与工程学院亚稳材料制备技术与科学国家重点实验室河北秦皇岛066004

采用DSC、XRD和TEM等手段研究了喷射电沉积制备的5.1 nm纳米晶Co78Ni22合金的热稳定性,并对其热力学参数进行了分析与计算。结果表明,该纳米Co-Ni合金具有良好的热稳定性,以10℃/min加热时的DSC放热峰值对应温度为389.9℃,放热焓为14.2... 详细信息

采用DSC、XRD和TEM等手段研究了喷射电沉积制备的5.1 nm纳米晶Co78Ni22合金的热稳定性,并对其热力学参数进行了分析与计算。结果表明,该纳米Co-Ni合金具有良好的热稳定性,以10℃/min加热时的DSC放热峰值对应温度为389.9℃,放热焓为14.26 J·g-1,晶粒长大激活能为269.1 kJ·mol-1。在加热过程中,温度为340℃时,合金晶粒尺寸急剧长大,同时ε相向α相转变,相变的结束温度约为370℃,高温形成的α相在随后冷却中不发生转变。DSC测定的晶粒长大为相变结束后的α相晶粒长大,其激活能与自扩散激活能相近,因此晶粒长大由晶内扩散控制。

关键词：纳米Co78Ni22合金热稳定性晶粒长大

Casual associations between blood metabolites and colon cancer

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第5期16卷 1995-2005页

作者： Ke-Yue Hu Yi-Quan Cheng Zhi-Long Shi fu-Peng ren Gang-Feng xiao Department of Hematology and Oncology Ningbo No.2 HospitalNingbo 315000Zhejiang ProvinceChina

BACKGROUND Limited knowledge exists regarding the casual associations linking blood metabolites and the risk of developing colorectal *** To investigate causal associations between blood metabolites and colon *** The study utilized a two-sample Mendelian randomization(MR)analysis to investigate the causal impact of 486 blood metabolites on colorectal *** primary method of analysis used was the inverse variance weighted *** further validate the results several sensitivity analyses were performed,including Cochran's Q test,MR-Egger intercept test,and MR robust adjusted profile *** additional analyses were conducted to ensure the reliability and robustness of the *** After rigorous selection for genetic variation,486 blood metabolites were included in the MR *** found Mannose[odds ratio(OR)=2.09(1.10-3.97),P=0.024],N-acetylglycine[OR=3.14(1.78-5.53),P=7.54×10^(-8)],X-11593-O-methylascorbate[OR=1.68(1.04-2.72),P=0.034],1-arachidonoylglycerophosphocholine[OR=4.23(2.51-7.12),P=6.35×10^(-8)]and 1-arachidonoylglycerophosphoethanolamine 4[OR=3.99(1.17-13.54),P=0.027]were positively causally associated with colorectal cancer,and we also found a negative causal relationship between Tyrosine[OR=0.08(0.01-0.63),P=0.014],Urate[OR=0.25(0.10-0.62),P=0.003],N-acetylglycine[0.73(0.54-0.98),P=0.033],X-12092[OR=0.89(0.81-0.99),P=0.028],Succinylcarnitine[OR=0.48(0.27-0.84),P=0.09]with colorectal cancer.A series of sensitivity analyses were performed to confirm the rigidity of the *** This study showed a causal relationship between 10 blood metabolites and colorectal cancer,of which 5 blood metabolites were found to be causal for the development of colorectal cancer and were confirmed as risk *** other five blood metabolites are protective factors.

关键词： Metabolites Colon cancer Mendelian randomization Genome-wide association studies Casual

The Effects of Astragalus membranaceus and Tripterygium hypoglaucum on NK Activity in Systemic Lupus Erythematosus

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Integrative Medicine 1995年第1期1卷 111-113页

作者： Zhao xiao-zhong (赵小忠)(Department of Dermatology ,General Air Force Hospital .Beijing )(100036)Liu fu-ren(刘辅仁)(Department of Dermatology ,2nd Affiliated Hospital of Xi’an Medical University, Xi’an)(710006) Department of Dermatology General Air Force Hospital Beijing Department of Dermatology 2nd Affiliated Hospital of Xi’an Medical University Xi’an

The natural killer cell activity of peripheral blood mononuclear cells from 28 patients withsystemic lupus erythematosus was measured using enzyme-release assay. The patients exhibited obvi-ously decreased natural killer cell activity compared with the healthy subjects in the control group. Thenatural killer cell dysfonction was related to steroidal therapy, but not to three auto-antibodies. The re-lease of a soluble natural killer cytotoxic factor by the peripheral blood mononuclear cells was tested bycytotoxicity assay induced in K256 cells. This release was significantly lower in the test group than in thecontrol group. Pre-incubation of peripheral blood mononuclear cells with Astragalus membranaceus andTripterygium hypoglaucum considerably enhanced natural killer cytotoxicity by stimulating the release ofsoluble cytotoxic factors.

关键词： Astragalus membranaceus Tripterygium hypoglaucum. natural killer cell activity nat-ural killer cytotoxic fector systemic lupus erythematosus

Trace formula of the integro-differential operator on a quantum graph

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 311-318页

作者： WEI Li-xiao YANG Chuan-fu School of Mathematics and Statistics Nanjing University of Science and TechnologyNanjing 210094China.

In this paper we study the eigenvalue problem for integro-differential operators on a lasso *** trace formula of the operator is established by applying the residual technique in complex analysis.

关键词： integro-differential operators eigenvalue trace formula

在线全文

学校读者我要写书评

暂无评论

热处理节能与环保技术进展

金属热处理 2009年第1期34卷 1-6页

作者：廖波肖福仁燕山大学材料科学与工程学院河北秦皇岛066004

综述了我国机械工业的发展给热处理行业所带来的机遇,对比分析了国内外热处理在节能环保方面的主要差距,提出了自己的建议,供热处理同仁参考。

关键词：热处理节能环保

Solvent transport dynamics and its effect on evolution of mechanical properties of nitrocellulose(NC)-based propellants under hot-air drying process

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第2期32卷 262-270页

作者： Enfa fu Mingjun Yi Qianling Liu Zhenggang xiao Key Laboratory of Special Energy Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094People's Republic of China

Appropriate drying process with optimized controlling of drying parameters plays a vital role in the improvement of the quality and performance of propellant ***,few research on solvent transport dynamics within NC-based propellants was reported,and its effect on the evolution of mechanical properties was not interpreted *** study is conducted to gain a comprehensive understanding of hot-air drying for NC-based propellants and clarify the effect of temperature on solvent transport behavior and further the change of mechanical properties during *** drying kinetic curves show the drying time required is decreased but the steady solvent content is increased and the drying rate is obviously increased with the increase of hot-air temperatures,indicating hot-air temperatures have a significant effect on drying kinetics.A modified drying model was established,and results show it is more appropriate to describe solvent transport behavior within NC-based ***,two linear equations were established to exhibit the relationship between solvent content and its effect on the change of tensile properties,and the decrease of residual solvent content causes an obvious increase of tensile strength and tensile modulus of propellant products,indicating its mechanical properties can be partly improved by adjustment of residual solvent *** outcomes can be used to clarify solvent transport mechanisms and optimize drying process parameters of double-based gun propellants.

关键词： Nitrocellulose-based propellants Solvent transport dynamics Mechanical properties Drying kinetics Effective solvent diffusion coefficient