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101.
102.
The present study used differential scanning calorimetry, thermogravimetric analysis, and UV spectrometry to examine: i) the encapsulation of an organic UV filter 1-(4-methoxyphenyl)-3-(4- tert-butylphenyl)propane-1,3-dione (avobenzone) within modified dextrin and ii) the characteristics of these inclusion complexes (MDA). The properties of avobenzone emulsions with and without encapsulation in modified dextrin, the in vitro UV protection factor, dissolution and release, and the skin penetrability of avobenzone were also examined. The presence of inclusion complexes significantly decreased the tendency of the UV filter to penetrate the skin. In addition, such inclusion complexes should effectively prevent skin damage from radiation extending from the UVA to the UVC. 相似文献
103.
Journal of Thermal Analysis and Calorimetry - We quantified the thermal stability of 2,2′-azobis(2,4-dimethyl)valeronitrile (ADVN) under isothermal conditions through thermogravimetry (TG),... 相似文献
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The three-dimensional (3D) coupled analysis of simply-supported, functionally graded piezoelectric material (FGPM) circular hollow sandwich cylinders under electro-mechanical loads is presented. The material properties of each FGPM layer are regarded as heterogeneous through the thickness coordinate, and obey an exponent-law dependent on this. The Pagano method is modified to be feasible for the study of FGPM sandwich cylinders. The modifications are as follows: a displacement-based formulation is replaced by a mixed formulation; a set of the complex-valued solutions of the system equations is transferred to the corresponding set of real-valued solutions; a successive approximation method is adopted to approximately transform each FGPM layer into a multilayered piezoelectric one with an equal and small thickness for each layer in comparison with the mid-surface radius, and with the homogeneous material properties determined in an average thickness sense; and a transfer matrix method is developed, so that the general solutions of the system equations can be obtained layer-by-layer, which is significantly less time-consuming than the usual approach. A parametric study is undertaken of the influence of the aspect ratio, open- and closed-circuit surface conditions, and material-property gradient index on the assorted field variables induced in the FGPM sandwich cylinders. 相似文献
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This paper considers the problem of determining operation and maintenance schedules for a containership equipped with various subsystems during its sailing according to a pre-determined navigation schedule. The operation schedule, which specifies working time of each subsystem, determines the due-date of each maintenance activity and the maintenance schedule specifies the actual start time of each maintenance activity. The main constraints are subsystem requirements, workforce availability, working time limitation, and inter-maintenance time. To represent the problem mathematically, a mixed integer programming model is developed. Then, due to the complexity of the problem, we suggest a heuristic algorithm that minimizes the sum of earliness and tardiness between the due-date and the actual start time for each maintenance activity. Computational experiments were done on various test instances and the results are reported. In particular, a case study was done on a real instance and a significant amount of improvement is reported over the experience based conventional method. 相似文献
109.
Indium-mediated allenylation of arylacyl bromides in a route for the synthesis of substituted furans
Mei-Huey Lin Chung-Kai KuoYen-Chih Huang Yu-Ting TsaiChang-Hsien Tsai Kung-Yu LiangYi-Syuan Li Tsung-Hsun Chuang 《Tetrahedron》2014
A three-step, single purification procedure has been developed for the concise synthesis of substituted furans from arylacyl bromides. 相似文献
110.
McLain Derek R. Brossard Tom W. Tsai Yifen Condon Nicholas J. Canaday Jodi L. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2169-2174
Journal of Radioanalytical and Nuclear Chemistry - Two methods were used to evaluate the age of 75Se sealed source material. Both methods utilized gamma spectroscopy to determine the quantity of... 相似文献