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71.
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针对新型装甲装备通用质量特性评价指标体系难以确定的问题,在明确评价指标体系构建原则的基础上,结合新型装甲装备特点,确定了通用质量特性初始评价指标及指标筛选要求,运用QFD将新型装甲装备通用质量特性需求映射为评价指标筛选要求,采用粗糙集理论(Rough Set Theory,RST)确定了指标筛选重要度,考虑到关联度的不确定性及多个专家估计值的平均值和估计值的波动程度,将贝叶斯理论引入关系矩阵的确定中,用区间数确定了关联度,进行了评价指标筛选,构建了新型装甲装备通用质量特性评价指标体系,为新型装甲装备通用质量特性评价奠定了基础。 相似文献
73.
Structural elucidation of new urinary tamoxifen metabolites by liquid chromatography quadrupole time‐of‐flight mass spectrometry 下载免费PDF全文
Jianghai Lu Chunji He Genye He Xiaobing Wang Youxuan Xu Yun Wu Ying Dong Gangfeng Ouyang 《Journal of mass spectrometry : JMS》2014,49(7):570-578
In this study, tamoxifen metabolic profiles were investigated carefully. Tamoxifen was administered to two healthy male volunteers and one female patient suffering from breast cancer. Urinary extracts were analyzed by liquid chromatography quadruple time‐of‐flight mass spectrometry using full scan and targeted MS/MS techniques with accurate mass measurement. Chromatographic peaks for potential metabolites were selected by using the theoretical [M + H]+ as precursor ion in full‐scan experiment and m/z 72, 58 or 44 as characteristic product ions for N,N‐dimethyl, N‐desmethyl and N,N‐didesmethyl metabolites in targeted MS/MS experiment, respectively. Tamoxifen and 37 metabolites were detected in extraction study samples. Chemical structures of seven unreported metabolites were elucidated particularly on the basis of fragmentation patterns observed for these metabolites. Several metabolic pathways containing mono‐ and di‐hydroxylation, methoxylation, N‐desmethylation, N,N‐didesmethylation, oxidation and combinations were suggested. All the metabolites were detected in the urine samples up to 1 week. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
74.
Fused Perylene–Phthalocyanine Macrocycles: A New Family of NIR‐Dyes with Pronounced Basicity 下载免费PDF全文
Jörg Schönamsgruber Dr. Harald Maid Prof. Dr. Walter Bauer Prof. Dr. Andreas Hirsch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(51):16969-16979
The synthesis and characterization of a new type of chromophore, namely PePc consisting of a central phthalocyanine core and four fused perylene–bisimide (PBI) units is described for the first time. The entire architecture represents a highly extended conjugated heterocyclic π‐system with C4h symmetry. In order to guarantee pronounced solubility in organic solvents the corresponding PBI units were bay‐functionalized with tert‐butylphenoxy substituents. Next to the metal‐free macrocycle, PePcH2, also metallated macrocycles PePcM (M=Zn, Ni, Pb, Ru, Fe) were synthesized. The extensive fusion of the corresponding aromatic building blocks to the very large extended π‐system leads to a very narrow HOMO–LUMO gap and as a consequence to transparency in the visible but light absorption in the NIR region. Significantly, the azomethine N‐atoms N1?N4 of PePcM and PePcH2 are highly basic. The corresponding tetraprotonated systems can only be deprotonated with very strong non‐nucleophilic bases such as phosphazene bases. In the protonated forms PePcMH44+ and PePcMH64+ the absorption maximum is shifted back to the visible region due to the loss of conjugation. The experimental findings were corroborated with quantum mechanical calculations. 相似文献
75.
康经武 《分析测试技术与仪器》2014,(3):125-127
就如何理解和看待新时期分析测试中心的定位和发展,如何解决分析测试中心在结构和管理上存在的固有问题提出了粗略的观点.希望对分析测试中心的发展起到抛砖引玉的作用. 相似文献
76.
Determinations of soil moisture witli the aid of neutron moisture meters require calibrations under real conditions. Some efficient methods for calibrating such moisture gauges are described and working examples are presented. 相似文献
77.
In this paper a new ring-shaped harmonic oscillator for spin 1/2 particles is studied, and the corresponding eigenfunctions and eigenenergies are obtained by solving the Dirac equation with equal mixture of vector and scalar potentials. Several particular cases such as the ring-shaped non-spherical harmonic oscillator, the ring-shaped harmonic oscillator, non-spherical harmonic oscillator, and spherical harmonic oscillator are also discussed. 相似文献
78.
A new method to protect the copyright of digital museum based on digital holography is proposed. The Fresnel hologram of watermark image is embedded in the object to be protected through discrete wavelet transform (DWT). After the watermark detection, the copyright information appears in the reconstructed hologram. With the higher redundancy feature in the hologram, the proposed technique can actually survive several kinds of image processing. Experimental results prove that the presented method has good robustness in image protection. 相似文献
79.
Pu Zhou Zilun Chen Xiaolin Wang Xiao Li Zejin Liu Xiaojun Xu Jing Hou Zongfu Jiang 《中国光学快报(英文版)》2008,6(7)
We demonstrate a scalable architecture for coherent combining of pulsed fiber lasers.A new method for generating synchronous pulsed fiber lasers by direct phase modulation is proposed and investigated.It is shown that phase modulated mutually coupled laser array can be a steady synchronous pulsed fiber laser source.The synchronous pulsed fiber lasers are coherently combined with an invariable phase difference of π in adjacent lasers.Neither active phase control nor polarization control is taken in our experiment. 相似文献
80.