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21.
ZHAO ChuanZhen XIU XiangQian ZHANG Rong XIE ZiLi LIU Bin LIU ZhanHui YAN HuaiYue & ZHENG YouDou Jiangsu Provincial Key Laboratory of Advanced Photonic Electronic Materials 《中国科学:物理学 力学 天文学(英文版)》2010,(1)
The paper reports the setting up of a model of fluid dynamic for GaN HVPE system and the simulation. It is found that when the direction of gravity is opposite to the direction of GaCl flow inlet,there exits a distance at which the uniformity of the deposition is optimal. Here the good uniformity of the deposition is obtained when the distance between the substrate and GaCl inlet is 5 cm. The parameters of gas flow used in growing GaN are also optimized. In addition, the influence of gravity and buoyancy on... 相似文献
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针对化纤企业生产、检测的需要,研制了一种粘纤单丝数目自动检测系统。系统采用环形光源,从周围均匀照明经静电和高速风两次分离的粘纤,再由成像物镜将分离的粘纤清晰成像至高速面阵CCD传感器靶面上,基于Directshow技术自行编制出图像采集程序。利用自主研发的图像处理软件,处理粘纤图像信息,自动计算其单丝的数目,并给出判别结果。在图像处理方面采用分行消包络阈值分割法和连通域跟踪计数法,解决了粘纤计数中的胶丝重叠、分叉等关键技术难题,保证了计数准确率。该系统具有精度高、检测速度快等特点。 相似文献
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Ai-hua Zhang Zhi-ming Ma Ling Kong Hong-lei Gao Hui Sun Xiang-qian Wang Jing-bo Yu Ying Han Guang-li Yan Xi-jun Wang 《Biomedical chromatography : BMC》2020,34(2):e4724
Lipid metabolism has a significant function in the central nervous system and Alzheimer's disease (AD) is an age-related senile disease characterized by central nerve degeneration. The pathological development of AD is closely related to lipid metabolism disorders. To reveal the influence of Kai-Xin-San (KXS) on lipid metabolism in APP/PSI transgenic mice and potential therapeutic targets for treating AD, brain tissue samples were collected and analyzed by high-throughput lipidomics based on UPLC–Q/TOF-MS. The collected raw data were processed by multivariate data analysis to discover the potential biomarkers and lipid metabolic profiles. Compared with the control wild-type mouse group, nine potential lipid biomarkers were found in the AD model group, of which seven were up-regulated and two were down-regulated. Orally administrated KXS can reverse the changes in these potential biomarkers. Compared with the model group, a total of six differential metabolites showed a recovery trend and may be potential targets for KXS to treat AD. This study showed that high-throughput lipidomics can be used to discover the perturbed pathways and lipid biomarkers as potential targets to reveal the therapeutic effects of KXS. 相似文献
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Epidural scarring occurs inevitably in the defect after spinal laminectomy, and thus how to prevent or reduce it becomes a challenging topic. In the present study, an injectable hydrogel and its dexamethasone(DEX)-loaded hydrogel systems were adopted to prevent epidural scarring in a postlaminectomy rat model. The hydrogel system composed of poly(D,L-lactic acid-co-glycolic acid)-poly(ethylene glycol)-poly(D,L-lactic acid-co-glycolic acid)(PLGA-PEG-PLGA) triblock copolymers was a free-flowing sol at room temperature, and spontaneously turned into a semi-solid gel at body temperature. A lumbar 3 total laminectomy was performed on Sprague Dawley(SD) rats, and the efficacy of the injectable hydrogel with or without drugs in preventing epidural scar formation was evaluated via the gross anatomical observation and histological examination at one month post-surgery. The results demonstrate that the use of hydrogel alone reduced epidural scarring significantly, whereas the efficacy of the DEX-loaded hydrogels presented an irregular dose-dependency of drug and even the inappropriate drug doses resulted in the negative results. Therefore, the present study confirms that the PLGA-PEGPLGA hydrogel holds potential as a barrier device to decrease peridural scarring, and reveals that the sustained delivery of the steroid hormone DEX to prevent surgery-related adhesions in the laminectomy defect is complex. Moreover, our in vivo studies also remind the researchers to pay attention to the irregular dose-dependency of the hormone drugs. 相似文献
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Mao-xiang Jing Hong-ai Zhai Zhi-chao Pi Jing-quan Li Li-li Chen Xiang-qian Shen Xiao-ming Xi Ke-song Xiao 《Russian Journal of Applied Chemistry》2016,89(7):1183-1188
The LiFePO4/carbon fiber (LFP/CF) cathodes were prepared by using activated carbon fiber cloth as current collector in place of conventional Al foil. The electrochemical properties of LFP/CF electrodes were analyzed by the cyclic voltammetry and galvanostatic charge/discharge tests. The results indicate that the activated carbon fiber cloth with high specific surface area and high porosity makes the LFP/CF electrode that possesses higher mass loading of 18–21 mg cm–2 and stronger redox reaction ability compared with Al foil-based electrode. The LFP/CF electrode shows excellent rate performance and cycle stability. At 0.1C, the discharge capacity is up to 190.1 mAh g–1 that exceeds the theoretical capacity due to the combination effect of battery and capacitor. Furthermore, the LFP/CF electrode shows an initial capacity of 150.4 mAh g–1 at 1C with a capacity retention of 74.7% after 425 cycles, which is higher than 62.4% for LFP/Al foil electrode, and an initial discharge capacity of 130 mAh g–1 at 5C with a capacity retention of 61.5% after 370 cycles. But this composite electrode is not suitable for charging/discharging at higher rate as 10C due to too much mass loading. 相似文献
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