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排序方式: 共有146条查询结果,搜索用时 15 毫秒
141.
Letícia Caramori Cefali Daniele Cristina Barbosa de Oliveira Cristina Maria Franzini Janaína Artem Ataíde Patrícia Moriel Priscila Gava Mazzola 《Journal of Dispersion Science and Technology》2018,39(8):1149-1152
The aim of the present study was to carry out stability tests and in vitro sun protection factor (SPF) evaluations of formulations containing free or microencapsulated chemical sun filters to improve their use. To this end, three formulations were developed and subjected to stability studies. The most stable formulation was chosen as a vehicle for free and microencapsulated chemical sun filters, and subjected to further stability studies and in vitro SPF assays. The SPF values were approximately 12 and 11 for formulations containing free and encapsulated sun filters, respectively, and both types were stable under stress. Chemical sun filters can be microencapsulated, which may aid in generating innovative sunscreen formulations. 相似文献
142.
Norouzi Amir Mohammad Siavashi Majid Etebari Ata Khaliji Oskouei MohammadHasan 《Journal of Thermal Analysis and Calorimetry》2020,141(5):1493-1508
Journal of Thermal Analysis and Calorimetry - Flow through packed beds of granular materials, and for instance, granular activated carbon (GAC), is of great importance and has various applications... 相似文献
143.
Alaa S. Abd‐El‐Aziz Hany M. Mohamed Shawkat Mohammed Shamsulhaq Zahid Athar Ata Ahmed H. Bedair Ahmed M. El‐Agrody Pierre D. Harvey 《Journal of heterocyclic chemistry》2007,44(6):1287-1301
144.
An inventory control problem for deteriorating items with back-ordering and financial considerations
This paper investigates the effects of time value of money and inflation on the optimal ordering policy in an inventory control system. We proposed an economic order quantity model to manage a perishable item over the finite horizon planning under which back-ordering and delayed payment are assumed. The demand and deterioration rates are constant. The present value of total cost during the planning horizon in this inventory system is modeled first, then a three phases solution procedure is proposed to derive the optimal order and shortage quantities, and the number of replenishment during the planning horizon. Finally, the proposed model is illustrated through numerical examples and the sensitivity analysis is reported to find some managerial insights. 相似文献
145.
Nara Singh BS Liu Z Wadsworth R Grawe H Brock TS Boutachkov P Braun N Blazhev A Górska M Pietri S Rudolph D Domingo-Pardo C Steer SJ Ataç A Bettermann L Cáceres L Eppinger K Engert T Faestermann T Farinon F Finke F Geibel K Gerl J Gernhäuser R Goel N Gottardo A Grębosz J Hinke C Hoischen R Ilie G Iwasaki H Jolie J Kaşkaş A Kojouharov I Krücken R Kurz N Merchán E Nociforo C Nyberg J Pfützner M Prochazka A Podolyák Z Regan PH Reiter P Rinta-Antila S Scholl C Schaffner H Söderström PA Warr N 《Physical review letters》2011,107(17):172502
A β-decaying high-spin isomer in (96)Cd, with a half-life T(1/2)=0.29(-0.10)(+0.11) s, has been established in a stopped beam rare isotope spectroscopic investigations at GSI (RISING) experiment. The nuclei were produced using the fragmentation of a primary beam of (124)Xe on a (9)Be target. From the half-life and the observed γ decays in the daughter nucleus, (96)Ag, we conclude that the β-decaying state is the long predicted 16(+) "spin-gap" isomer. Shell-model calculations, using the Gross-Frenkel interaction and the πν(p(1/2),g(9/2)) model space, show that the isoscalar component of the neutron-proton interaction is essential to explain the origin of the isomer. Core excitations across the N=Z=50 gaps and the Gamow-Teller strength, B(GT) distributions have been studied via large-scale shell-model calculations using the πν(g,d,s) model space to compare with the experimental B(GT) value obtained from the half-life of the isomer. 相似文献
146.
Sonay Yanar Ata Sevim B. Boyacioglu Mesude Saglam Soma Mukhopadhyaya Ashok Chatterjee 《Superlattices and Microstructures》2008
The problem of an electron interacting with longitudinal-optical (LO) phonons is investigated in an N-dimensional quantum dot with symmetric Gaussian confinement in all directions using the Rayleigh–Schrödinger perturbation theory, a variant of the canonical transformation method of Lee–Low–Pines, and the sophisticated apparatus of the Feynman–Haken path-integral technique for the entire range of the coupling parameters and the results for N=2 and N=3 are obtained as special cases. It is shown that the polaronic effects are quite significant for small dots with deep confining potential well and the parabolic potential is only a poor approximation of the Gaussian confinement. The Feynman–Haken path-integral technique in general gives a good upper bound to the ground state energy for all values of the system parameters and therefore is used as a benchmark for comparison between different methods. It is shown that the perturbation theory yields for the ground state polaron self-energy a simple closed-form analytic expression containing only Gamma functions and in the weak-coupling regime it provides the lowest energy because of an efficient partitioning of the Gaussian potential and the subsequent use of a mean-field kind of treatment. The polarization potential, the polaron radius and the number of virtual phonons in the polaron cloud are obtained using the Lee–Low–Pines–Huybrechts method and their variations with respect to different parameters of the system are discussed. 相似文献