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排序方式: 共有498条查询结果,搜索用时 0 毫秒
1.
Fluorenophanes derived from 2,7-bis-(bromomethyl)-9,9′-diheptyl-9H-fluorene and various diols exhibit excellent photoluminescence properties. 相似文献
2.
We propose a thermodynamic framework for describing the microwave drying process of aqueous dielectrics based on Maxwell-Lorentz Field equations and mixture theory. Several issues are discussed such as the form of entropy equation; the constitutive relations for the macroscopic electric polarization vectors, Cauchy stresses, heat fluxes, internal momentum supplies, etc., for each component of the mixture: porous solid, water and gas in different regions; and the interfacial jump conditions between different regions in the mixture. A brief examination of the status of material frame indifference within the context of our framework is presented. 相似文献
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4.
Josinira A. Amorim Osvaldo Chiavone-Filho Márcio L.L. Paredes Krishnaswamy Rajagopal 《Fluid Phase Equilibria》2007
High-pressure density data for cyclohexane + n-hexadecane mixtures at a wide temperature range was modeled with several classical equations of state (EOS) and correlative models. A modification for softening the co-volume and another for a volume scaling of the Peng–Robinson EOS (VS-PR) were proposed. The VS-PR model is able to correlate the pure component experimental data employing only five adjustable parameters, with root-mean-square deviation (RMSD) between calculated and experimental densities essentially within the experimental error. This result is superior to widely used approaches, i.e., a six parameter Tait model and six parameter volume translations (temperature and pressure dependent) for Peng–Robinson and Patel–Teja EOS. The VS-PR model also represents well the isobaric thermal expansion and the isothermal compressibility coefficients of the pure cyclohexane, a small naphthenic substance as well as a long chain n-alkane hydrocarbon, n-hexadecane. When modeling the mixture data, the use of VS-PR model of pure components along with the Redlich–Kister expansion, truncated at the first term, the density was correlated within a RMSD only 60% greater than the experimental error. The proposed model is able to accurately represent all the tested mixture data with a relatively small number of parameters. 相似文献
5.
S. S. Vernekar S. D. Jolad S. Rajagopal 《Monatshefte für Chemie / Chemical Monthly》1962,93(1):271-273
Zusammenfassung Mittels der Konversion aromatischer Amine in die entsprechenden Benzaldehyde, einer Methode, die vonBeech entwickelt und von uns auf Haloaniline erweitert wurde, werden in einfacher, eleganter Weise zwei Halogenbenzaldehyde dargestellt.2. Mitt.:S. D. Jolad undS. Rajagopal, Naturwiss.48, 645 (1961). 相似文献
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K. R. Rajagopal 《Journal of Elasticity》1994,36(3):271-301
In this paper, we study inhomogeneous deformations within the context of finite thermoelasticity with a view towards highlighting the developments of boundary layer like structures. We find that such structures manifest themselves by virtue of the material's ability to shear soften or shear stiffen. When the material moduli depend both on the temperature and the stretch, their effects can either reinforce or mitigate one another, thereby leading to the accentuation or annihilation of the boundary layer structure. 相似文献
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Zusammenfassung Es wird die Synthese von 13-Oxo-4-methoxy-13H-benzo[i]-furo[2,3-a]xanthen beschrieben.
Furano compounds XVI
The synthesis of 13-oxo-4-methoxy-13H-benzo[i]furo[2,3-a]-xanthene is recorded.相似文献
10.
R. Rajagopal S. A. Siddiqui Thomas Daniel R. J. Lahoti K. V. Srinivasan 《Journal of molecular catalysis. A, Chemical》2004,210(1-2):165-169
Regioselective monobromination of aromatic substrates with N-bromosuccinimide has been achieved in excellent isolated yields (84–98%) using phosphotungstic acid supported on zirconia as a novel heterogeneous catalyst. The catalyst has been characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), surface area and acidity measurements. Remarkably, the new catalyst system described brought about the side-chain bromination of aromatics to afford bromomethyl arenes in excellent yields (86–98%) without the need for a radical initiator. Recovery and recylability of the catalyst have been well established. 相似文献