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131.
A. Abd El-Haliem M. A. Naim M. R. El-Aasser Z. Awaad G. E. Whiebey 《Isotopes in environmental and health studies》2013,49(6):276-286
The decay of 140 57La (40.3 h) to levels in 140 58Ce has been studied in the present work. The energies and relative intensities of 37 gamma-rays following the β? decay of 140 57La have been measured with high precision using Ge(Li) and HP.Ge spectrometers. log (ft) values of beta decay were determined from our gamma ray intensities using the beta branchings and a decay scheme is deduced. The sum-peak technique has been used to determine k-conversion coefficient of the transition 1596.41 keV and was found to be 6.98x10?4 in an excellent agreement with the theoretical value 6.9×10?4 obtained by Pauli for pure E2 transition. 相似文献
132.
Dragan Sekulić Vlastimir Dedović Srdjan Rusov Slaviša Šalinić Aleksandar Obradović 《Applied Mathematical Modelling》2013,37(18-19):8629-8644
The paper analyzes the effects of vibrations on the comfort of intercity bus IK-301 users. Evaluation of vibration effects was carried out according to the criteria set out in the 1997 ISO 2631-1 standard for comfort in public means of transport. Comfort is determined for the space of a driver, passenger in the middle part of the bus and passenger in the rear overhang. Also, the allowable exposure time to vibrations in drivers for the reduced comfort criterion was determined according to the 1978 ISO 2631-1 standard. The bus spatial oscillatory model with ten degrees of freedom was developed for the needs of the analysis. Bus excitation was generated applying the Power Spectral Density of the asphalt-concrete road roughness, as described by the H. Braun model. The allowable vibration exposure time for the driver’s body decreases as the spring stiffness of the driver’s seat suspension system increases. Simulation was performed using the MATLAB software. 相似文献
133.
This paper describes the mutual impact of Analytical Chemistry and several international written standards (norms and guides) related to knowledge management (CEN-CWA 14924:2004), social responsibility (ISO 26000:2010), management of occupational health and safety (OHSAS 18001/2), environmental management (ISO 14001:2004), quality management systems (ISO 9001:2008) and requirements of the competence of testing and calibration laboratories (ISO 17025:2004). The intensity of this impact, based on a two-way influence, is quite different depending on the standard considered. In any case, a new and fruitful approach to Analytical Chemistry based on these relationships can be derived. 相似文献
134.
TQM与ISO 9000的关系 总被引:2,自引:0,他引:2
王志坚 《新疆大学学报(理工版)》2003,20(3):331-333
随着经济全球化和WTO的到来.质量管理的对象已从原来“商品、服务的质量”扩大至“经营系统的质量”.因此,必须提高TQM(综合质量管理)水平,实施ISO9000.使我国企业质量管理的管理方法规范并与国际接轨,管理水平达到世界先进水平.文中介绍了综合质量管理的产生,运作需注意的问题。ISO9000质量标准和2000版标准的主要特点,最后讨论了TQM和ISO的关系. 相似文献
135.
Optical fibers and molded optics have been formed by using the Ga5Sb10Ge25Se60 base glass with appropriate thermal treatment to generate microcrystals. The crystal growth during the fiber drawing and molding process induces additional scattering losses in the short wavelength region, but does not have a significant effect beyond 6 μm. The molded optics have very good dimensional precision and the form defect is less than 0.5 μm peak-to-valley, which is excellent particularly for optics designed for operating at 8-12 μm. 相似文献
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138.
A non-separative, fast and inexpensive spectrofluorimetric method based on the second order calibration of excitation-emission fluorescence matrices (EEMs) was proposed for the determination of carbaryl, carbendazim and 1-naphthol in dried lime tree flowers. The trilinearity property of three-way data was used to handle the intrinsic fluorescence of lime flowers and the difference in the fluorescence intensity of each analyte. It also made possible to identify unequivocally each analyte. Trilinearity of the data tensor guarantees the uniqueness of the solution obtained through parallel factor analysis (PARAFAC), so the factors of the decomposition match up with the analytes. In addition, an experimental procedure was proposed to identify, with three-way data, the quenching effect produced by the fluorophores of the lime flowers. This procedure also enabled the selection of the adequate dilution of the lime flowers extract to minimize the quenching effect so the three analytes can be quantified. Finally, the analytes were determined using the standard addition method for a calibration whose standards were chosen with a D-optimal design. 相似文献
139.
A simplified mould flux glass composition used for the continuous casting of steel was synthesized and then characterized using X-ray powder diffraction (XRD) differential thermal analysis (DTA) and 19F and 29Si magic angle spinning nuclear magnetic resonance spectroscopy (MAS-NMR). DTA showed the glass to have a low glass transition temperature and to crystallize readily at 600 °C. XRD of the heat-treated glass showed it to crystallize to cuspidine. 19F MAS-NMR showed the principal fluorine species to be F-Ca(n) with no evidence of Si-F or Al-F species. Fluoride ions therefore, complex calcium in this glass, rather than forming non-bridging fluorines. The network connectivity of the glass was calculated on this basis and found to be 2.07 this would be expected to correspond to a Q2 Si species which was supported by the 29Si data that gave a chemical shift of −78 ppm corresponding to Q2 Si. 相似文献
140.
Distribution of electronic states in amorphous Cd-As thin films on the basis of optical measurements
Transmission and fundamental reflectivity studies, completed on amorphous Cd-As thin films, allowed us to obtain parameters describing the fundamental absorption edge, i.e. the optical pseudogap EGopt, Urbach energy EU and exponential edge parameter ET. All these data, together with the results of earlier transport measurements, have been utilized in developing simple models of electronic structure (distribution of electronic states) for amorphous Cd-As thin films of various compositions. 相似文献