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91.
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TANG Qingguo Shen Shangyue Wang Lijuan LIANG Jinsheng Ding Yan Meng Junping LI Guosheng WANG Man 《中国稀土学报(英文版)》2004,22(Z3)
The magnetic liquid was prepared with ferric salt by inorganic gel technology. The effect of the doped rare earth elements on the properties of magnetic particles was analyzed. The magnetic liquid was composed with clay mineral into magnetic mineral composites. The crystal structure and micro-morphology of the nanoparticles were studied by XRD and TEM. The results show that the crystal structure of the magnetic particles doped 0.5 % of lanthanum is more complete, and the magnetic response capability is higher with doping agent. At the same time, the possibility of the clay mineral magnetic composites as the carrier of target drug was probed. 相似文献
93.
Fluxing agents of zinc borate, antimony oxide, galss frit A and glass frit B, with different melting or softening point temperatures, were added into MgO-Al2O3-SiO2/boron phenol formaldehyde resin (MAS/BPF) composites to lower the formation temperature of eutectic liquid phase and promote the ceramification of ceramifiable composites. The effects of fluxing agents on the thermogravimetric properties, phase evolution, and microstructure evolution of MAS / BPF composites were characterized by TG-DSC, XRD and SEM analyses. The results reveal that the addition of a fluxing agent highly reduces the decomposition rate of MAS / BPF composites. Fluxing agents lower the formation temperatures of liquid phases of ceramifiable MAS / BPF composites obviously, and then promote the ceramification and densification process. The final residues of composites are ceramic surrounded by large amount of glass phases. 相似文献
94.
沈一丁 《陕西科技大学学报》1989,7(1):22-28
本文研究了两个系列的热塑型聚氨酯—聚醚酯氨(ET)和聚酯氨酯(ES)的结构形态与相分离程度,提出了一种确定硬段含量(W_h)的IR方法。与NMR法、投料比法比较,三者得到非常吻合的结果。此外本文还研究了W_h、M_(n·■)、拉伸及热历史对相分离程度的影响。 相似文献
95.
本工作测定了不同温度下硫酸高铈与对二甲苯反应的速率常数及表观活化能Ea= 111.5kJ·m ol- 1。在动力学测定的的基础上确定了此反应的速率方程为d[PTAL]/dt= k[PX][Ce(IV)] 相似文献
96.
提供了人工神经网络的一种算法-误差反向传播算法的数学推导方法及上机实现步骤. 相似文献
97.
本文介绍6例在苏联切尔诺贝利核电站事故期间受到放射性铯内污染的我国驻外人员,在本实验室接受活体测量和服用普鲁士蓝促排的观察结果。6例内污染者分两组分别于受污染后的第114天和第272天开始用药,在大约一个月期间,每人共服药54g(给药方式:每次服1g,每日3次,6天为一个疗程,间隔6天,共用药3个疗程)。观测结果表明,在促排期间,6例内污染者体内铯的生物半排期均明显缩短,~(131)Cs 的生物半排期由对照期(用药前)的54—123d 缩短到28—65d,~(134)Cs 由对照期的42—117d 缩短到23—69d;6例体内放射性铯的累积活度相对于同期未用药条件下的累积活度减少2—21%。 相似文献
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OBJECTIVE: A mutant soybean line (A16) low in linolenic acid content (2% of oil by weight) was developed to increase oil oxidative stability. It was unknown whether serum lipid and lipoprotein concentrations in humans would be affected should A16 soybean oil (A16 oil) replace commercial soybean oil in diets. This study was conducted to examine the hypothesis that in free-living normolipidemic women, the consumption of A16 oil at approximately 10% of energy intake (en%) would not affect serum lipids and lipoproteins differently than would the consumption of the same amount of a commercial soybean oil with 7% of linolenic acid content. DESIGN: Fifteen free-living female college students consumed the soybean oil daily with regular meals for 9 weeks in different orders, with each test oil being eaten for 3 weeks. During the study, 13 en% was provided by each test oil and a total of 35 en% was from dietary fat. Serum concentrations of total cholesterol, high-density lipoprotein cholesterol (HDL cholesterol), low-density lipoprotein cholesterol (LDL cholesterol) and triacylglycerides (TAG) were measured. Serum total fatty acid patterns were analyzed as well. RESULTS: Each of the three test oils decreased serum total cholesterol, LDL cholesterol and TAG concentrations from the baseline values. The feeding of A16 and commercial soybean oils decreased serum HDL cholesterol significantly compared with coconut oil (p < 0.05). Dietary inclusion of coconut oil increased serum myristic acid significantly more than did either soybean oil (p < 0.01). Serum arachidonic acid concentrations were significantly greater with A16 consumption than with commercial soybean oil consumption (p < 0.001). CONCLUSION: A16 and commercial soybean oils both diminished serum HDL cholesterol. Although the fatty acid composition differed between the two soybean oils, A16 oil and commercial oil had similar effects on serum concentrations of lipoproteins and lipids. With increased oxidative stability, A16 oil is a good alternative to commercial soybean oil. 相似文献