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Shijie Liu Georg Roeder Gulnur Aygun Kristian Motzek Peter Evanschitzky Andreas Erdmann 《Optik》2012,123(10):928-931
A 3D model is set up to simulate the exposure process of inclined/rotated UV lithography for negative SU-8 resists. The formation of inclined resist pillars and microstructures with truncated cone shapes is simulated based on a 3D exposure model in combination with a post exposure bake model for chemically amplified resists and the Mack development model. As one of the interesting applications employing this promising lithography technique for MEMS fabrication, a solid microneedle for drug delivery is simulated. 相似文献
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Ding Yunqiao Li Junying Wang Shijie Junzhang Mu Qiuhong Wang Jingui 《Structural chemistry》2018,29(5):1499-1510
Structural Chemistry - The reaction mechanisms of several amino acids (Asn, Gln, Arg, His, and Lys) in the collagen with aldehyde were studied using density functional theory method. Based on the... 相似文献
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Tungsten doped mesoporous SBA‐16 as novel heterogeneous catalysts for oxidation of cyclopentene to glutaric acid 下载免费PDF全文
Novel heterogeneous tungsten species in mesoporous silica SBA‐16 catalysts based on ship‐in‐a‐bottle methodology are originally reported for oxidizing cyclopentene (CPE) to glutaric acid (GAC) using hydrogen peroxide (H2O2). For all W‐SBA‐16 catalysts, isolated tungsten species and octahedrally coordinated tungsten oxide species are observed while WO3 crystallites are detected for the W‐SBA‐16 catalysts with Si/ W = 5, 10, and 20. The specific surface areas and the corresponding total pore volumes decrease significantly as increasing amounts of tungsten incorporated into the pores of SBA‐16. Using tungsten‐substituted mesoporous SBA‐16 heterogeneous catalysts, high yield of GAC (55%) is achieved with low tungsten loading (for Si/W = 30, ~13 wt%) for oxidation of CPE. The W‐SBA‐16 catalysts with Si/W = 30 can be reused five times without dramatic deactivation. In fact, low catalytic activity provided by bulk WO3 implies that the highly distributed tungsten species in SBA‐16 and the steric confinement effect of SBA‐16 are key elements for the outstanding catalytic performance. 相似文献
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Back Cover: Improved Electrochromic Performance of Poly(3,4‐ethylenedioxythiophene) by Incorporating a Three‐Dimensionally Ordered Macroporous Structure (Chem. Asian J. 20/2016) 下载免费PDF全文
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In this paper, plasma concentration, plasma protein binding rate, body distribution, and excretion of both oral and intravenous administration of rats were determined by high performance liquid chromatography (HPLC) combining with UV detector. The blood drug concentration of oral and intravenous administration was summarized. The bioavailability of T1/2 was approximately 0.75?hr. At the meanwhile, the bioavailability was about 18.84?±?2.21%. The plasma protein binding rate of 1-methyl hydantoin was about 24.36?±?0.93%, belonging to low protein binding drug. The result shows that 1-methyl hydantoin can be rapidly distributed in various organs and tissues and quickly eliminated within 6?hr without accumulation in the organs. Its discharge from the urine and feces was 16.58?±?4.48% and 3.37?±?0.71%, respectively. All of the results showed that the recovery rate, liner relationship, specificity, stability, and precision of the method were good. The study also proved that 1-methyl hydantoin has been eliminated quite faster in rats. 相似文献