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排序方式: 共有247条查询结果,搜索用时 8 毫秒
1.
The glow curve structures for LiF:Mg,Cu,Na,Si TL detectors with various dopant concentrations and sintering temperatures were investigated for the improvement of the glow curve structure and sensitivity of the TL detector. The dopant concentrations were varied over the following ranges: Mg (0–0.25 mol%), Cu (0–0.07 mol%), Na and Si (0–1.5 mol%). With increasing Cu concentration, the intensity of the main peak was intensified and reached a maximum at a concentration of 0.05 mol%. The high-temperature peak was reduced. The dependency of the main peak intensity on the Mg concentration exhibits a sharp maximum at 0.2 mol%. The intensity of the high-temperature peak tends to rise slightly with increasing Mg concentration. It was found that the optimum concentrations of the dopants in the LiF:Mg,Cu,Na,Si TL material are Mg: 0.2 mol%, Cu: 0.05 mol%, Na and Si: 0.9 mol%. The dependency of the main peak intensity on sintering temperature exhibits a very sharp maximum at 830°C. The high-temperature peak was rapidly reduced after 825°C. 相似文献
2.
轴端沟槽底部激光强化工艺参数优化研究 总被引:1,自引:1,他引:0
分析了选用不同激光能量密度对HT300进行表面强化处理时,材料表面呈现的四种状况;未相变硬化、相变硬化、表面微熔与表面熔凝的金相组织。根据工艺要求,选取相变硬化方法对轴端沟槽底表面进行处理。分析了工件激光处理方法并通过试验研究,寻找轴端沟槽底部激光强化工艺参数;激光功率(P)、光斑直径(D)及扫描速度(V)的优化组合。硬度测试及耐磨性能试验表明:激光相变处理和激光熔凝处理后轴端沟槽底部表面较表面感应淬火硬度分别提高7%和34%,绝对磨损体积分别下降了13%和25%。实践证实,对轴端沟槽底部激光相变硬化处理方法较其他表面处理方法工艺简单,加工工件符合技术要求,试验结果对零件表面处理提供了可靠依据。 相似文献
3.
Most of the common classes of organic compounds chromatograph normally on Superoxes. There is no tailing or adverse effect from excessively different activity different activity coefficients. Superoxes are therefore universal phases for gas chromatography. This is also expressed by a wide useful temperature range from ~50° to ~300°. High MW Superox-4 has a MAOT about 20° higher than the lower MW Superox-0.1. Several applications illustrating the versatility of Superox phases in (GC)2 are presented. 相似文献
4.
Y. Kuwahara H. Fukami R. Howard S. Ishii F. Matsumura W.E. Burkholder 《Tetrahedron》1978,34(12):1769-1774
Chemical an spectroscopic evidence is presented to show that 2,3-dihydro-2,3,5-trimethyl-6-(1-methyl-2-oxobutyl)-4H-pyran-4-one (10) is the sex pheromone produced by the female drugstore beetle, Stegobium paniceum L. 相似文献
5.
6.
在自动测量或自动测试系统开发过程中,会经常遇到不同的智能仪器所配备的程控接口有所不同,本文针对近几年来先后推出的带USB接口的智能仪表,以Rohde&Schwarz公司生产的AM300任意波形发生器为例,在介绍了它实现任意波形发生器功能和特点的基础上,描述了利用Rohde&Schwarz公司提供的AM300 LabVIEW驱动程序子VI,在LabVIEW8.5开发环境下通过USB接口设计任意波形发生器程序方法,经应用证明该方法简单实用,对从事自动测试程序设计者具有参考借鉴价值. 相似文献
7.
Cross-target effect has been one of the major mechanisms of drug toxicity, this has necessitated the design of inhibitors that are specifically tailored to target particular biomolecules. 6-(2,4-difluorophenoxy)-5-((ethylmethyl)pyridine-3-yl)-8-methylpyrrolo[1,2-a] pyrazin-1(2H)-one (Cpd38) is an inhibitor possessing high inhibition rate and tailored specificity towards bromodomain-containing protein 4 (BRD4). In this research, we used an array of computational techniques to provide insight at the atomistic level the specific targeting of BRD4 by Cpd38 relative to the binding of Cpd38 with E1A binding protein P300 (EP300); another bromodomain-containing protein (BCP). Comparatively, binding of Cpd38 improved the conformational stability and compactness of BRD4 protein when compared to the Cpd38 bound EP300. Also, Cpd38 induced a conformational change in the active site of BRD4 that facilitated a complementary pose between Cpd38 and BRD4 suitable for effective atomistic interactions. Expectedly, thermodynamic calculations revealed that the Cpd38-BRD4 system had higher binding energy (−36.11 Kcal/mol) than the Cpd38-EP300 system with a free binding energy of −15.86 Kcal/mol. Noteworthy is the opposing role Trp81 (acting as hydrogen bond acceptor) and Pro1074 (acting as hydrogen bond donor) found on the WPF and LPF loops respectively play in maintaining Cpd38 stability. Furthermore, the hydrogen bond acceptor/donator ratio was approximately 4:1 in Cpd38-BRD4 system compared with 2:1 in Cpd38-EP300 system. Taken together, atomistic insights and structural perspectives detailed in this report supplements the experimental report supporting the improved selectivity of Cpd38 for BRD4 ahead of other BCPs while providing leeway for the future design of BET selective agents with better pharmacological profile. 相似文献
8.
《电子技术与软件工程》2017,(8)
火电厂快速减负荷(fast cutback,FCB)功能是大型机组不可缺少的重要安全保障,通过对波黑斯坦纳瑞300MW燃煤机组FCB功能控制要求的分析,对DEH控制系统的改进。 相似文献
9.
Dr. Manuela Leticia Kim Dr. Deicy Barrera Dr. Mutsumi Kimura Prof. Dr. Juan P. Hinestroza Prof. Dr. Karim Sapag Dr. Eugenio Hernán Otal 《化学:亚洲杂志》2021,16(9):1086-1091
We report on a detailed textural analysis of mechanochemically synthesized MOF-199 including N2 adsorption-desorption and CO2 adsorption isotherms data at 77 K and 273 K (up to atmospheric pressure), respectively, and CH4 adsorption data at 298 K (up to 35 bar). We used the isotherm adsorption data to determine the micropore volume of the MOF-199 structures, to establish their methane uptake capacity and to understand how these properties depended on the Ethanol/BTC ratio used during the synthesis. The maximum methane uptake capacity for our specimens was recorded at 130 v/v at 35 bars. These results open an avenue for a better understanding of alternative manufacturing processes of MOF structures for gas storage applications. 相似文献
10.