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1.
Xiao-Lei Qiu Zi-Rui Fan Yang-Yang Liu Ding-Fu Wang Shi-Xin Wang Chun-Xia Li 《International journal of molecular sciences》2021,22(8)
A self-nanoemulsifying drug delivery system (SNEDDS) was developed to enhance the absorption of heparin after oral administration, in which heparin was compounded with phospholipids to achieve better fat solubility in the form of heparin-phospholipid (HEP-Pc) complex. HEP-Pc complex was prepared using the solvent evaporation method, which increased the solubility of heparin in n-octanol. The successful preparation of HEP-Pc complex was confirmed by differential scanning calorimetry (DSC), Fourier-transform infrared (FT-IR) spectroscopy, NMR, and SEM. A heparin lipid microemulsion (HEP-LM) was prepared by high-pressure homogenization and characterized. HEP-LM can enhance the absorption of heparin after oral administration, significantly prolong activated partial thromboplastin time (APTT) and thrombin time (TT) in mice, and reduce fibrinogen (FIB) content. All these outcomes indicate that HEP-LM has great potential as an oral heparin formulation. 相似文献
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Zhongchao Fu Xiaodong Li Mu Zhang Qi Zhu Ji-Guang Li Jiao He Xing'an Wang Xudong Sun 《Journal of the American Ceramic Society》2021,104(6):2689-2701
An easy albeit quite effective deionization suspension treatment was adopted to alleviate the detrimental effects related to the hydrolysis of Y2O3 in an aqueous medium. Fabrication of highly transparent Y2O3 ceramics with a fine grain size via air pre-sintering and post–hot isostatic pressing (HIP) treatment without using any sintering additive was achieved using the treated suspensions. The hydrolysis issue of Y2O3 powder in an aqueous medium was effectively alleviated by using deionization treatment, and a well-dispersed suspension with a low concentration of dissolved Y3+ species was obtained. The dispersed suspensions were consolidated by the centrifugal casting method, and the green bodies derived from the suspension of 35.0 vol% solid loading showed an improved homogeneity with a relative density of 52.1%. Fully dense Y2O3 transparent ceramic with high transparency was obtained by pre-sintering consolidated green compacts at a low temperature of 1400°C for 16 h in air followed by a post-HIP treatment at 1550°C for 2 h under 200 MPa pressure. The sample had a fine average grain size of 690 nm. The in-line transmittance of the sample reached 83.3% and 81.8% at 1100 nm and 800 nm, respectively, very close to the theoretical values of Y2O3. 相似文献
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Yueqiang LI Chao GAO Bin WU Yushuai WANG Haibo ZHENG Ming XUE Yuling WANG 《等离子体科学和技术》2021,23(2):25501-37
The turbulent boundary layer control on NACA 0012 airfoil with Mach number ranging from 0.3 to 0.5 by a spanwise array of dielectric barrier discharge(DBD)plasma actuators by hot-film sensor technology is investigated.Due to temperature change mainly caused through heat produced along with plasma will lead to measurement error of shear stress measured by hot-film sensor,the correction method that takes account of the change measured by another sensor is used and works well.In order to achieve the value of shear stress change,we combine computational fluid dynamics computation with experiment to calibrate the hot-film sensor.To test the stability of the hot-film sensor,seven repeated measurements of shear stress at Ma = 0.3 are conducted and show that confidence interval of hot-film sensor measurement is from-0.18 to 0.18 Pa and the root mean square is 0.11 Pa giving a relative error 0.5%over all Mach numbers in this experiment.The research on the turbulent boundary layer control with DBD plasma actuators demonstrates that the control makes shear stress increase by about 6%over the three Mach numbers,which is thought to be reliable through comparing it with the relative error 0.5%,and the value is hardly affected by burst frequency and excitation voltage. 相似文献
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邓乐善 《中国水能及电气化》2021,(1):56-58
针对民乐县农村人饮机井水位自动供水系统控制中存在的可靠性低、成本高等问题,文章结合深井泵提取地下水进行供水的实际情况,提出了软启动控制柜+浮球开关+微电脑时间控制器改进的思路和方法,运用效果良好。 相似文献
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采用有限元模拟和实验研究了挤压钛合金弯曲管件。通过实验验证了工件的形状和尺寸精度,并通过有限元模拟分析了工艺参数对挤出过程中变形体的平均压应力分布情况和挤出弯管件的曲率半径的影响规律。结果表明:有限元模拟中,弯管件的曲率半径误差为6.03%,弯管直径误差为3.82%;在靠近定径带处,平均压应力呈非均匀分布;在焊合腔内,靠近细分流孔区域的平均压应力小于靠近粗分流孔区域的平均压应力,平均压应力的大小顺序在通过粗、细分流孔前后相反;在模具结构固定不变时,弯管件的曲率半径随挤压速度的减小而增大,不随挤压温度的变化而变化。 相似文献
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谭金军 《自动化技术与应用》2021,40(1):181-183
为进一步提升企业思想政治教育工作的信息化水平,本文详细介绍了企业思想政治教育系统的数据库设计方案,以便更加充分地发挥各种多媒体教学设备在企业思想政治教育工作方面的优势。 相似文献
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