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Benzotriazolization of 2,4-dihydroxyacetophenone and 2,4-dihydroxybenzophenone has given dibenzotriazolized products: 3,5- [di (2H-benzotriazole-2-yl)]2,4-dihydroxyacetophenone, and 3,5-[di (2H-benzotriazole-2-yl)] 2,4-dihydroxybenzophenone. These compounds are expected to be effective and useful UV absorbers as they both have the 2 (2-hydroxyphenyl)2H-benzotriazole unit and the 2-hydroxybenzophenone (or acetophenone) unit in the molecule. The compounds were characterized by their spectral behavior and particularly by careful study of their UV spectrum.  相似文献   
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The Moving Particle Semi-implicit (MPS) method performs well in simulating violent free surface flow and hence becomes popular in the area of fluid flow simulation. However, the implementations of searching neighbouring particles and solving the large sparse matrix equations (Poisson-type equation) are very time-consuming. In order to utilize the tremendous power of parallel computation of Graphics Processing Units (GPU), this study has developed a GPU-based MPS model employing the Compute Unified Device Ar...  相似文献   
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Polymer morphology has a unique role in macromolecular science. Because it deals primarily with images of microstructure, revealing actual organization in its inherent complexity rather than as oversimplified models, it provides a special wealth of information from which to draw inferences on molecular and other mechanisms involved in its formation and on the consequences for properties. The essential first step is to image the microstructure to allow the eye-brain combination to use its outstanding ability to interpret complex textural patterns. Not only have continual gains in fundamental understanding stemmed from corresponding advances in our ability to reveal and study morphology but so have insights leading to improved properties. These themes are illustrated with recent results for both pure and applied topics. The origin of spherulitic growth, the principal determinant of texture and thus properties in polymers, is a long-standing, sometimes controversial, issue. Now study of an academic system, monodisperse paraffins, has clearly negated the long-standing hypothesis of the responsibility of “impurities” in the melt. It also strongly supports previous suggestions that the essential cause is divergence of adjacent dominant lamellae from their branch points, due to the pressure of uncrystallized molecular cilia. The value of morphological studies in the development of commercial materials is illustrated, firstly, for advanced polyethylene fibers, both compacted and individual, in which novel longitudinal defects have been discovered, and then by details of impact-related failure in polypropylene copolymers.  相似文献   
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This study compared the transduction efficiencies of an adeno-associated viral (AAV) vector, which was pseudotyped with an AAV1 capsid and encoded the green fluorescent protein (GFP), with a lentiviral (LV) vector, which was pseudotyped with a VSV-G envelop and encoded the discosoma red fluorescent protein (dsRed), to investigate which viral vector transduced the lateral hypothalamus or the amygdala more efficiently. The LV-dsRed and AAV1-GFP vector were mixed and injected into the lateral hypothalamus or into the amygdala of adult rats. The titers that were injected were 1 × 108 or 1 × 109 genomic copies of AAV1-GFP and 1 × 105 transducing units of LV-dsRed.  相似文献   
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This paper reports an experimental study on catalytic conversion of carbon dioxide to methanol,ethanol and acetic acid.Catalysts having different catalytic functions were synthesized and combined in different ways to enhance the selectivity to desired products.The combined catalyst system possessed the following functions:methanol synthesis,Fischer-Tropsch synthesis,water-gas-shift and hydrogenation.Results showed that the methods of integrating these catalytic functions played an important role in achieving the desired product selectivity.We speculate that if methanol synthesis sites were located adjacent to the C-C chain growth sites,the formation rate of C2 oxygenates would be enhanced.The advantage of using a high temperature methanol catalyst PdZnAl in the combined catalyst system was demonstrated.In the presence of PdZnAl catalyst,the combined catalyst system was stable at 380°C.It was observed that,at high temperature,kinetics favored oxygenate formation.The results implied that the process can be intensified by operating at high temperature using Pd-based methanol synthesis catalyst.Steam reforming of the byproduct organics was demonstrated as a means to provide supplemental hydrogen.Preliminary process design,simulation,and economic analysis of the proposed CO2 conversion process were carried out.Economic analysis indicates how ethanol production cost was affected by the price of CO2 and hydrogen.  相似文献   
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