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排序方式: 共有10000条查询结果,搜索用时 8 毫秒
981.
Vladimir B. Arion Alexey A. Nazarov Christian G. Hartinger Gerald Giester Bernhard K. Keppler 《应用有机金属化学》2003,17(9):723-724
For the unsymmetrical title compound, 1‐bromo‐1′‐[(2S)‐N‐(1‐hydroxy‐3‐methylbutane‐2‐yl)]‐ferroceneamide, two independent molecules were found in the asymmetric unit. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
982.
N. V. Baranova S. A. Bogdanova V. G. Bandorin A. V. Kostochko 《Russian Journal of Applied Chemistry》2005,78(10):1659-1661
Single crystals of nitramine fillers for special-purpose polymeric composites are characterized by the surface energy and its constituents and also by the acidity of their surface. 相似文献
983.
Jacquelyn A. Carioscia Lauren Schneidewind Casey O'Brien Robert Ely Caitlin Feeser Neil Cramer Christopher N. Bowman 《Journal of polymer science. Part A, Polymer chemistry》2007,45(23):5686-5696
The ability to prepare high Tg low shrinkage thiol–ene materials is attractive for applications such as coatings and dental restoratives. However, thiol and nonacrylated vinyl materials typically consist of a flexible backbone, limiting the utility of these polymers. Hence, it is of importance to synthesize and investigate thiol and vinyl materials of varying backbone chemistry and stiffness. Here, we investigate the effect of backbone chemistry and functionality of norbornene resins on polymerization kinetics and glass transition temperature (Tg) for several thiol–norbornene materials. Results indicate that Tgs as high as 94 °C are achievable in thiol–norbornene resins of appropriately controlled chemistry. Furthermore, both the backbone chemistry and the norbornene moiety are important factors in the development of high Tg materials. In particular, as much as a 70 °C increase in Tg was observed in a norbornene–thiol specimen when compared with a sample prepared using allyl ether monomer of analogous backbone chemistry. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5686–5696, 2007 相似文献
984.
The method of numerical integration of the classical equations of motion was used to study interaction of a model two-electron atom with ultrashort laser pulses. Mechanisms and specific features of the ionization process were analyzed in a broad range of laser-field parameters. 相似文献
985.
Nynke A. M. Verhaegh Jeroen S. van Duijneveldt Jan K. G. Dhont Henk N. W. Lekkerkerker 《Physica A》1996,230(3-4):409-436
Mixtures of colloidal silica spheres and polydimethylsiloxane in cyclohexane with a colloid-polymer size ratio of about one were found to phase separate into two fluid phases, one which is colloid-rich and one which is colloid-poor. In this work the phase separation kinetics of this fluid-fluid phase separation is studied for different compositions of the colloid-polymer mixtures, and at several degrees of supersaturation, with small angle light scattering and with light microscopy. The small angle light scattering curve exhibits a peak that grows in intensity and that shifts to smaller wave vector with time. The characteristic length scale that is obtained from the scattering peak is of the order of a few μm, in agreement with observations by light microscopy. The domain size increases with time as
, which might be an indication of coarsening by diffusion and coalescence, like in the case of binary liquid mixtures and polymer blends. For sufficiently low degrees of supersaturation the angular scattering intensity curves satisfy dynamical scaling behavior. 相似文献
986.
987.
A. N. Shchetinin 《Mathematical Notes》1993,54(1):747-753
Translated from Matematicheskie Zametki, Vol. 54, No. 7, pp. 124–135, July, 1993. 相似文献
988.
The NOAA National Status and Trends (NS&T) Program determines the current status of, and changes over time in the environmental health of U.S estuarine and coastal waters. Concentrations of organic and inorganic contaminants are determined in bivalves, bottom-dwelling fish and sediments. The quality of the analytical data generated by the NS&T Program is over-seen by the performance-based Quality Assurance Project, which is designed to document sampling protocols, analytical procedures, and laboratory performance, and to reduce intralaboratory and interlaboratory variation. All NS&T cooperating laboratories are required to participate in yearly intercomparison exercises. The analysis of reference materials, such as the National Research Council of Canada's Certified Reference Materials (CRMs) and National Institute of Standards and Technology's (NIST) Standard Reference Materials (SRMs), and of control materials, is required. Because of the need for marine matrix reference materials and standards, NOAA contributed to the production of eight NIST SRMs and seven internal standard solutions. Analytical data from all control materials and all matrix reference materials are reported to the Program office. 相似文献
989.
A deflecting system formed by two parallel-plate capacitors on opposite sides of an optoelectronic element that alters the
energy of a beam of charged particles, is calculated numerically. The conditions for correcting the chromatic beam spreading
in the plane of the target are found. Good agreement with the results of an approximate analytical calculation is demonstrated.
Zh. Tekh. Fiz. 67, 86–88 (December 1997) 相似文献
990.
V. G. Zhuravlev 《Journal of Mathematical Sciences》1997,83(6):750-761
For a generating Dirichlet vector series with coefficients equal to the number of representations of a quadratic form by another
one we abtain a decomposition into the product of a finite number of Dirichlet L-functions and an infinite number of matrix
polynomials. The coefficients of the polynomials are the Eichler-Brandt matrices of the basis double cosets of the local orthogonal
Hecke rings.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 212, 1994, pp. 97–113.
Translated by N. Yu. Netsvetaev. 相似文献