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61.
在20℃条件下,运用电导测定方法及非线性动力学模型进行数据处理,得到了在不同浓度十六烷基三甲基溴化胺(CTAB)胶束水溶液中正脂肪酸乙酯(甲酸乙酯,乙酸乙酯,丙酸乙酯,丁酸乙酯及正戊酸乙酯)碱性水解反应的速率常数.依据离子交换模型(PIE)理论讨论了在第一和第二临界胶束浓度(CMC)时,CTAB对正脂肪酸乙酯碱性水解反应速率的影响及规律性. 相似文献
62.
蒙脱土改性聚丙烯共混体系的可纺性及染色性研究 总被引:1,自引:0,他引:1
用X-射线衍射仪研究了蒙脱土在聚丙烯中的插层情况;对蒙脱土改性聚丙烯的多组分共混体系的可纺性及染色性作了比较。结果表明,聚丙烯/马来酸酐接枝聚丙烯/有机蒙脱土复合材料的质量分数组成为78.5%/13.5%/1.5%,加入质量分数为6.5%聚酯离聚物的共混体系具有较好的可纺性,且蒙脱土与聚酯离聚物对聚丙烯纤维的染色性改善具有协同作用,较聚丙烯/聚酯离聚物体系的染色性更好。 相似文献
63.
SULi SONGShuguang SONGBiao ZHOUDingwu HAOJianrong 《科学通报(英文版)》2004,49(12):1307-1310
“Qinling Group (?)” in Songshugou region in the north of the Shangdan Fault consists predominantly of amphibolite with or without garnet and amphibole-plagioclase gneiss and intercalated with lensiod blocks of garnet pyroxenite, where the famous Songshugou dunite body occurs (Fig. 1). Petrographic study reveals that garnet pyroxenite is the representative rock of early 相似文献
64.
目的:比较澳洲大蠊与美洲大蠊中总糖含量的差异。方法:采用苯酚-硫酸法测定总糖含量。结果:澳洲大蠊中总糖平均含量为139.6 mg/g,美洲大蠊的为127.6 mg/g,两种蜚蠊的总糖含量差异无统计学意义。结论:两种蜚蠊中总糖含量丰富,且二者的含量比较差异无统计学意义。 相似文献
65.
66.
Mengyang Liu Yuanli Chen Xiaoxiao Yang Ling Zhang Tao Zhao Buchang Zhao Lifu Jia Yan Zhu Xiumei Gao Boli Zhang Xiaoju Li Rong Xiang Jihong Han Yajun Duan 《科学通报(英文版)》2014,59(13):1366-1373
Clinical observations indicate that DanHong Injection (DHI) can increase blood flow and reduce various syndromes in patients with cardiovascular disease. How- ever, it still needs to define the function of DHI and the involved mechanisms in details, such as the protective effect on the development of primary abdominal aortic aneurysms (AAAs). In this study, we determined whether DHI is able to inhibit AAA in apoE knockout (apoE-/-) mice. Thirty apoE-/- male mice on high-fat diet (0.5 % cholesterol, 21% fat) were randomly divided into two groups and received i.p. injection of saline (100 μL/day) and DHI (100 μL/day), respectively, for 16 weeks. At the end of experiment, we determined the development of atherosclerosis in en face aorta and aneurysms,pathological morphology of arterial wall, and serum lipid levels. We also determined the expression of monocyte chemoattractant protein-1 (MCP-1), MMP-2, and MMP-9 mRNA in aortic wall using real-time RT-PCR. Our results indicated that high-fat diet induced the development of AAAs in apoE-/- mice, but the induction was totally blocked by DHI (P 〈 0.01). The result of staining of abdominal aortic cross sections showed that DHI main- tained the collagen content in arterial wall, thereby pre- venting the animals from the development of AAA. Although DHI had little effect on serum total- and LDL- cholesterol levels, it reduced the expression of MCP-1, MMP-2, and MMP-9 mRNA in aortic wall (P 〈 0.01). Taken together, our study suggests that DHI can inhibit the high-fat diet-induced AAA formation. The inhibitory effects may be related to the maintenance of the collagen content and inhibition of expression of AAA-related genes. Our study may suggest a new application of DHI in clinics. 相似文献
67.
段立松 《南京大学学报(自然科学版)》2014,(1):6-7,67
概述了氨酸法料床直接反应工艺的特点,并提出其后续优化措施,即将浓硫酸的稀释热用于液氨的汽化或将部分原料加热熔融生成料浆,采用两段湿法洗涤的手段对造粒尾气、干燥尾气和冷却尾气进行综合治理。采用上述改进措施后,能进一步提高热量的利用水平,明显提高了尾气的净化效果,实现洗涤液零排放。 相似文献
68.
提出了一种基于生成对抗网络的无载体信息隐藏方法.发送方用伪装图像和Improved Wasserstein GAN生成一张与秘密图像相同的图像,发送方发送伪装图像,接收方收到伪装图像后用生成器生成和秘密图像视觉上相同的图像.与现有的信息隐藏方法相比,该方法不需要修改载体,能够有效地抵抗隐写分析工具的检测,能够达到秘密信息安全传输的目的. 相似文献
69.
Xueling Shi Tao Chen Lingqian Zhang Suping Duan Jiang Liu Zhaohai He 《科学通报(英文版)》2014,59(34):4790-4796
An ion flux dropout near the dipolarization front (DF) at around XGSM =- 11 RE in the Earth' s plasma sheet was observed by Time History of Events and Macroscale Interaction during substorms (THEMIS) on March 31, 2009. The ion differential energy fluxes at energies from 450 eV to 150 keV measured by the ESA and SST instruments from THC began to decrease about 2 s before the detection of the DF and reached a local minimum 6 s later. Then, the ion fluxes gradually increased to form a dropout around the DF. The spatial extent of the dropout was about 4,000 km. For energies above 20 keV, the ion fluxes after the dropout are greater than those before it, contrary to the fluxes at energies below 20 keV. The associated ion density variation indicates that the ion flux dropout coincides with the ion density dropout. Taking advantage of multipoint observations, THD, THC, and THE detected the same DF consecutively. Only THC detected an obvious ion flux dropout; THD observed an indistinct one about 2 s before THC; no high-energy (E 〉 30 keV) ion flux dropout was observed by THE. Our study suggests that the ion flux dropout may evolve with the earthward-propagating DF, and its properties can depend on locations relative to the DF. 相似文献
70.
For the improvement of accuracy and better fault-tolerant performance, a global position system (GPS)/vision navigation (VISNAV) integrated relative navigation and attitude determination approach is presented for ultra-close spacecraft formation flying. Onboard GPS and VISNAV system are adopted and a federal Kalman filter architecture is used for the total navigation system design. Simulation results indicate that the integrated system can provide a total improvement of relative navigation and attitude estimation performance in accuracy and fault-tolerance. 相似文献