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131.
Liu Yuren Lu Yanxin Xie Yali Wang Yonghai Du Youling Tan Jin Meng Bonian R. S. Seymour 《Journal of Radioanalytical and Nuclear Chemistry》1991,151(1):83-93
This paper introduces the principles, instrumentation, implementation, and industrial applications of an on-line thermal neutron prompt-gamma element analysis system (using a252Cf neutron source, Am–Be neutron source, or neutron generator). The energy resolution of the system at the H prompt-gamma full-energy photopeak (2.22325 MeV) is 3.6 keV. The concentration measurement error of Al2O3, FeO3, CaO, and SiO2 is ±0.3%, ±0.1%, ±0.4%, and ±0.4%, respectively. The system has been tested on-site at both the Shandong and the Zhengzhou Aluminium Works. Our preliminary on-site measurements confirm that the stability, reliability, measurement range, and accuracy of the system can meet the requirements of the aluminium production process. Facilitation of this measurement at aluminium plants is expected to reduce plant costs by over 3 million dollars annually through reduced energy consumption, more rapid qualification of pulps being mixed during the production process, and in reduced labor costs.Other participants of Shandong and Zhenghou Aluminium Works are: Wang Aili, Zengshen, Dei Jianguo and Lu Jinnan, Wang Deyu, Jin Hequan. 相似文献
132.
一个包含Smarandache函数的方程 总被引:2,自引:0,他引:2
对于任意正整数n,我们用S(n)表示Smarandache函数,即S(n)=min{m:n|m!}.本文的主要目的是运用初等方法研究方程∑_(d|n)S(d)=n的可解性,并给出它的所有正整数解. 相似文献
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136.
Yanlin Huang Kiwan Jang Wanxue Zhao Eunjin Cho Ho Sueb Lee Xigang Wang Dake Qin Ying Zhang Chanfang Jiang Hyo Jin Seo 《Journal of solid state chemistry》2007,180(12):3325-3332
Usually, Sm2+ ions could be reduced by heating the materials in reducing atmospheres. Exposure to ionizing radiations is also known to cause Sm3+→Sm2+ conversion. In this work, BaBPO5 doped with the samarium ion was prepared by high temperature solid-state reaction. Sm2+ ions were obtained by two different reduction methods, i.e., heating in H2 reduced atmosphere and X-ray irradiation. The measurements of X-ray diffraction (XRD), and scanning electron microscope (SEM) were investigated. It is found that the conversion of Sm3+→Sm2+ is very efficient in BaBPO5 hosts after X-ray irradiation. Sm2+ ions under these two reduction methods exhibit different characteristics that were studied by measurements of luminescence and decay. The results showed that the luminescence properties of Sm2+ ions in BaBPO5 were highly dependent on the sample preparation conditions. 相似文献
137.
Three novel zinc complexes [Zn(dbsf)(H2O)2] ( 1 ), [Zn(dbsf)(2,2′‐bpy)(H2O)]·(i‐C3H7OH) ( 2 ) and [Zn(dbsf)(DMF)] ( 3 ) (H2dbsf = 4,4′‐dicarboxybiphenyl sulfone, 2,2′‐bpy = 2,2′‐bipyridine, i‐C3H7OH = iso‐propanol, DMF = N,N‐dimethylformamide) were first obtained and characterized by single crystal X‐ray crystallography. Although the results show that all the complexes 1–3 have one‐dimensional chains formed via coordination bonds, unique three‐dimensional supramolecular structures are formed due to different coordination modes and configuration of the dbsf2? ligand, hydrogen bonds and π–π interactions. Iso‐propanol molecules are in open channels of 2 while larger empty channels are formed in 3 . As compared with emission band of the free H2dbsf ligand, emission peaks of the complexes 1–3 are red‐shifted, and they show blue emission, which originates from enlarging conjugation upon coordination. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
138.
Xiu‐Li Wang Ke‐Ke Yang Yu‐Zhong Wang Zhi‐Xuan Zhou Yong‐Dong Jin 《Journal of polymer science. Part A, Polymer chemistry》2004,42(14):3417-3422
A new biodegradable starch graft copolymer, starch‐g‐poly(1,4‐dioxan‐2‐one), was synthesized through the ring‐opening graft polymerization of 1,4‐dioxan‐2‐one onto a starch backbone. The grafting reactions were conducted with various 1,4‐dioxan‐2‐one/starch feed ratios to obtain starch‐g‐poly(1,4‐dioxan‐2‐one) copolymers with various poly(1,4‐dioxan‐2‐one) graft structures. The microstructure of starch‐g‐poly(1,4‐dioxan‐2‐one) was characterized in detail with one‐ and two‐dimensional NMR spectroscopy. The effect of the feed composition on the resulting microstructure of starch‐g‐poly(1,4‐dioxan‐2‐one) was investigated. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3417–3422, 2004 相似文献
139.
一种新型有机电致微腔结构的双模发射 总被引:4,自引:4,他引:0
采用结构Glass/DBR/ITO/NPB/NPB:Alq/Alq/Al制作了有机微腔电致发光器件。将空穴传输材料与发光材料以一定比例混合作为发光层,为了便于对比,在不改变有机层的膜厚的情况下同时制作了传统的异质结微腔器件,发现两种器件的发光光谱有很大不同,器件的复合效率与传统的异质结器件相比也得到了很大提高,这是因为将两种有机材料混合能消除界面势垒,提高器件的复合效率,从而提高了器件的发光性能,实现了微腔双模发射,且两个模式的半峰全宽分别为8nm和12nm。通过进一步优化器件结构可以实现微腔白光发射。 相似文献
140.
光纤加速度传感器研究进展 总被引:5,自引:0,他引:5
光纤加速度传感器与传统加速度传感器相比,不但能抗电磁干扰,而且体小、质轻、动态范围宽、精度高、能在恶劣环境下工作,因此受到各先进国家军事与商业领域的极大重视,各种实用的光纤加速度传感器不断涌现。主要有光强调制型和相位调制型两大类。光强调制式有反射式、透射式和偏振式等等。相位调制式有Mach-Zender干涉仪、Michelson干涉仪和Fabry-Perot干涉仪。有一维的,也有二维的;有与水听器组合在一起的,也有与光纤陀螺仪组合的光纤加速度传感器。最小的已经做到2.5cm长,直径仅0.25mm;测量精度已能达到1μg;共振频率可达到10kHz。为了克服温度不稳定性对测量精度的影响,人们采用了3×3耦合器解调法,双光路法,由单臂式改成推挽式等。一旦关键技术得以克服,光纤加速度传感器将会在惯性导航和其它领域发挥更重要的作用。本文将分别介绍目前各种类型光纤加速度传感器的结构、特点、走向实用化存在的问题。 相似文献