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1.
微量Y对Al—Li合金的析出相和力学性能的影响   总被引:1,自引:0,他引:1  
研究了Y(0.1、0.5wt-%)对Al-Li-Cu—Mg—Zr合金析出相与拉伸性能的影响结果表明:Y可使铸态合金晶粒细化:促进β′(Al_3Zr)相析出:抑制δ′(Al_3Li)相的长大速度:使S′(Al_2CuMg)相的分布均匀化.添加0.1%Y能改善合金塑性而不降低强度:添加0.5%Y可使强度提高而塑性不降低  相似文献   
2.
Li  Yixiang  An  Huanxiao  Wang  Xiaobing  Wang  Pan  Qu  Fei  Jiao  Yan  Zhang  Kun  Liu  Quanhong 《Nano Research》2018,11(2):1038-1056
Nano Research - Applying ultrasound (US) to drug delivery and disease therapy is important work. Sonodynamic therapy (SDT)—a comprehensive therapy using US and a sonosensitizer—exhibits...  相似文献   
3.
详细介绍了无刷直流电动机的过流保护电路和逻辑保护电路。实践应用表明,该 设计方案切实可行。  相似文献   
4.
介绍了采用Hontye IRAS系统对原(料)油进行智能快速分析以及在生产过程和全流程优化中的应用。Hontye IRAS系统可智能快速分析原油、柴油加氢原料、催化裂化原料和加氢裂化原料,并自动生成包含馏分油性质的原油简评和详评报告,制定原油加工方案及预测装置产品收率等。系统进行智能快速分析及时性强、准确性高、可靠性好、应用效果佳,为企业优化生产、降本增效提供有力支撑。  相似文献   
5.
In this work, crude polysaccharide extracts were extracted from pumpkin (Cucurbita moschata) fruit by hot water. After removal of proteins and purification, polysaccharides of pumpkin fruit (PP1‐1) were subjected to structural identification. Gas chromatography analysis indicated that PP1‐1 comprised of galactose (86.4%), and glucose (13.6%). The molecular weight of PP1‐1 was measured to be 0.87 × 104 Da by gel permeation chromatography. The inhibitory kinetic evaluation showed that it was non‐competitive inhibition of PP1‐1 on the α‐glucosidase‐catalysed hydrolysis of PNPG. The Michaelis–Menten constant (Km) was 0.106 m , and the inhibitory constants (Ki), 0.435 mg.  相似文献   
6.
Experimental investigations were performed on the overall cooling effectiveness of three effusion cooling test plates. The test plates had different hole-spacing (PS/d2 = 32.5 and 72), different deflection angle (β = 45° and 90°), and the same inclination angle (α = 30°). Although effusion cooling has been applied to advanced gas turbine combustors, its fundamental study seen in the open literature is limited. Using the infrared (IR) imaging technique, the current study documented distribution of the overall cooling effectiveness on the surfaces of above specified flat walls. Based on the IR measured cooling effectiveness data, different effusion cooling configurations (different PS/d2 and β) were evaluated and the optimum configuration was determined. The current work demonstrated that the infrared imaging technique served as an ideal method to detail cooling characteristics in the combustor heat transfer research.  相似文献   
7.
采用固定床反应器对煤焦进行部分氧化处理,然后测定氧化后煤焦在水蒸气和CO2中的气化行为,并用SEM,XRD和N2/CO2吸附对煤焦结构进行表征.结果表明,煤焦低温氧化处理可以显著改善煤焦的孔隙结构,大幅增加比表面积,降低煤焦的有序化和石墨化程度,从而提高其气化活性;并且随氧化程度( burnout)增加,煤焦气化活性不断增加.随氧化温度升高(>600℃),氧化过程逐渐过渡到扩散控制,O2主要在煤焦外表面反应,因而氧化几乎不会改变煤焦的结构,表面积略有增加,对其后续气化活性无明显影响.  相似文献   
8.
以正己醇作为引发剂,分别与环氧乙烷和环氧丙烷发生聚合,再以气体三氧化硫进行硫酸化反应,合成了正己醇聚氧乙烯醚硫酸钠(HE3S)以及正己醇聚氧丙烯醚硫酸钠(HP3S)2种阴非离子型表面活性剂。采用FTIR和1H NMR技术对表面活性剂结构进行了表征。通过平衡表面张力、动态表面张力和动态接触角研究了其水溶液的表面活性。实验结果表明,HE3S和HP3S在298 K下的临界胶束浓度分别为58.36 mmol/L和53.84 mmol/L,最低表面张力分别为33.91 m N/m和33.29 m N/m;由动态表面张力计算出的扩散系数,可知两种表面活性剂在水溶液中的吸附机理均属于混合动力控制吸附;当溶液浓度为150 mmol/L时,HE3S和HP3S的水溶液液滴在石蜡膜上可以短时间内快速铺展,其最低接触角分别达到64.5°和55.9°。  相似文献   
9.
Profiles of soluble proteins isolated from mature seeds of grape (Vitis vinifera L.) pomace were studied using two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE) coupled with matrix‐assisted laser desorption/ionisation time‐of‐flight mass spectrometry (MALDI–TOF–MS). Two‐dimensional gels stained with Coomassie brilliant blue revealed more than fifty protein spots. Four abundant protein spots showing low molecular weight (Mr) and wide isoelectric point (pI) were analysed by MALDI–TOF–MS, resulting in their identification. Taken together, these results suggest that identified proteins may be linked to seed development and metabolism, but more instructive is that they have some potential functions for future food application. These results provide some insights into conversion of grape processing wastes into useful products or even as raw material for other industries.  相似文献   
10.
As a rich source of polysaccharides, pumpkin pulp was used for the production of oligosaccharides. To investigate the prebiotic potential of the oligosaccharides, prepared by acid hydrolysis of polysaccharides from pumpkin pulp, the effect of the oligosaccharides on lactobacilli growth was studied. The oligosaccharides were composed of galactose (99.03%) and glucose (0.97%). The molecular weight distribution of the oligosaccharides showed a larger part of low molecular weight fraction in a range from 5000 to 324 Da than the polysaccharides, which gave the oligosaccharides higher solubility. The oligosaccharides showed good resistance to hydrolysis by artificial human gastric juice and α‐amylase, compared to the reference prebiotic inulin, and considerable capability to stimulate the growth of lactobacilli. In vitro studies showed that the number of lactobacilli was significantly greater than those in control medium when they were cultured in the medium supplemented with the oligosaccharides (P < 0.05), and there was no significant difference at the oligosaccharides group and the inulin group (P < 0.05).  相似文献   
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