排序方式: 共有27条查询结果,搜索用时 15 毫秒
1.
Thomas P J Linsinger Alexander Bernreuther Philippe Corbisier Marta Dabrio Håkan Emteborg Andrea Held Andrée Lamberty Gaida Lapitajs Marina Ricci Gert Roebben Stefanie Trapmann Franz Ulberth Hendrik Emons 《Accreditation and quality assurance》2007,12(3-4):167-174
The potential approaches for third-party assessment of reference material producers are revisited and the activities of the
Reference Materials (RM) Unit of the Institute for Reference Materials and Measurements (IRMM) to obtain accreditation to
ISO Guide 34 and ISO 17025 are described. Accreditation was related to the Unit as all matrix RM activities of the institute
are concentrated there. A management system was established that allows sufficient flexibility to be applicable to a wide
range of RMs while being precise enough to ensure compliance with ISO Guides 30, 31 and especially 34 and 35. Accreditation
was achieved in 2004 with independent scopes for testing and RM production and was confirmed and extended in 2005. The key
aspects of the RM Unit's management system for RM production are presented.
Presented at BERM-10, April 2006, Charleston, SC, USA 相似文献
2.
Stutzki F Otto HJ Jansen F Gaida C Jauregui C Limpert J Tünnermann A 《Optics letters》2011,36(23):4572-4574
A high-speed mode analysis technique is required to gain fundamental understanding of mode instabilities in high-power fiber laser systems. In this work a technique, purely based on the intensity profile of the beam, is demonstrated to be ideally suited to analyze fiber laser dynamics. This technique, together with a high-speed camera, has been applied to the study of the temporal dynamics of mode instabilities at high average powers with up to 20,000 frames per second. These measurements confirm that energy transfer between the fluctuating transversal modes takes place in millisecond-time-scale. 相似文献
3.
Self-induced transparency on the neon transition 2s
2(J=1)–2p
4(J=2) is studied both experimentally by investigating the propagation of 3-nsec laser pulses at 1.15 µm in an absorber discharge and theoretically by a numerical integration of Bloch's equations and the wave equation.—The application of linearly and circularly polarized light corresponds to the interaction with a quasi-nondegenerate and degenerate transition, respectively. Pulse shapes, delays, and transmittancevs. input peak intensity are found in quantitative agreement with the calculated data. While with linear light polarization all SIT characteristics clearly appear, with circular polarization the pulse break-up and the oscillation of transmittance due to optical nutations are washed out.—The homogeneous linewidth derived from pulse delay data agrees with the value from conventional measurements. The results prove SIT useful as a quantitative spectroscopic method.Work supported by the Deutsche Forschungsgemeinschaft 相似文献
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We have observed fluctuations in the output of individual modes of a multi-mode laser with homogeneously broadened gain weakly coupling these modes. Magnitude and distribution of the fluctuations are compared with results of current statistical models of a multi-mode laser. 相似文献
6.
Cavani L Ciavatta C Trubetskaya OE Reznikova OI Afanas'eva GV Trubetskoj OA 《Journal of chromatography. A》2003,983(1-2):263-270
Capillary zone electrophoresis (CZE) was used for characterisation of soil humic acid (HA) fractions obtained by coupling size-exclusion chromatography with polyacrylamide gel electrophoresis, on the basis of their molecular size and electrophoretic mobility. CZE was conducted using several low alkaline buffers as background electrolyte (BGE): 50 mM carbonate, pH 9.0; 50 mM phosphate, pH 8.5; 50 mM borate, pH 8.3; 50 mM Tris-borate+1 mM EDTA+7 M urea+0.1% sodium dodecyl sulphate (SDS), pH 8.3. Independently of BGE conditions, the effective electrophoretic mobility of HA fractions were in good agreement with their molecular size. The better resolution of HA were obtained in Tris-borate-EDTA buffer with urea and SDS. This results indicated that CZE, mostly with BGE-contained disaggregating agents, is useful for separating HAs in fractions with different molecular sizes. 相似文献
7.
On the basis of a Lagrangian formulation of Relativistic theory of direct interparticle interactions, a post-Newton correction (of order c–4) is found to the Bazaski lagrangian in the problem of two gravitating bodies.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 31–36, July, 1990. 相似文献
8.
Gawdzik A. Gaida S. Yurchuk N. M. Sofronkov A. N. 《Russian Journal of Applied Chemistry》2001,74(6):1064-1065
A high-performance gas diffusion electrode is fabricated by hot pressing with an asbestos laying used to provide uniform load in the process. The electrode was studied in cathodic reduction of oxygen in acidic electrolyte at various temperatures. 相似文献
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A classical, quasirelativistic Hamiltonian is found for a system of charged particles with intrinsic magnetic moments. It represents a generalization of the Darwin Hamiltonian and is the classical analog of the Breit Hamiltonian.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 73–76, November, 1973. 相似文献