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31.
32.
大港渣油掺兑催化油浆氧化沥青的研究 总被引:1,自引:0,他引:1
重油催化裂化外甩油浆中富含芳烃,可望在国产原油生产优质道路沥青上发挥作用。对大港环烷基渣油中掺兑一定比例的油浆后氧化改善道路沥青性质的可能性进行了研究,结果表明:渣油掺兑油浆氧化,不仅可以有效改善沥青延度,同时也为油浆的合理利用开辟了一条新途径。 相似文献
33.
H. Djidjelli A. Boukerrou A. Rabouhi R. Founas M. Kaci O. Zefouni N. Djillali L. Belmouhoub 《应用聚合物科学杂志》2008,107(3):1459-1465
The changes in mechanical properties, the thermal stability, and the water absorption capacity of poly (vinyl chloride)/olive residue flour composites were studied as a function of various residue olive flour ratios, i.e., 0, 5, 15, and 25% by weight taking into account the effect of benzylation chemical treatment of the filler. The study showed that composite samples prepared with the untreated filler exhibited higher tensile modulus and hardness compared with the neat resin, whereas elongation and tensile strength were observed to decline. On the other hand, the PVC hardness was found to increase with addition of the untreated olive residue flour (ORF), however the composite samples prepared with the benzylated flour exhibited lower hardness than those prepared with untreated olive residue. Moreover, the amount of absorbed water depends on the amount of filler in the composite. The comparison of the results obtained from the samples of F5, F20, and F30 formulations between the untreated and treated ORF indicated a reduction in absorbed water for the composite samples containing treated ORF with benzyl chloride. As a result, the mechanical properties of the treated composites were improved. Furthermore, the thermal characterization of the different samples carried out by color change test and thermogravimetric analysis revealed an increase in the onset temperatures of decomposition for the treated composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
34.
Abstract The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plantsobtained whose protein content was higher than 18.5%, the highest one was 21.44%. There were 3plants obtained whose protein content was lower than 11.5%, the lowest one was 10.96%. We cansee that the whole DNA of soybean transformed into wheat via ion beam implantation can inducethe increase in wheat protein content dramatically. The result also shows that the transformationefficiency of different gene types of wheat receptor varies greatly that the implanting time has acertain effect on the efficiency of transformation. 相似文献
35.
分析了铝电解槽修槽废渣的产生量、基本构成及污染特性,重点介绍了铝电解槽修槽废渣的处理处置方法和综合利用途径。 相似文献
36.
Michael L. Bates Michael J. Warwick George Shearer David J. Harwood Ira D. Herriman Raymond J. Heitzman David H. Watson 《Journal of the science of food and agriculture》1985,36(1):31-36
The synthetic growth promoter diethylstilboestrol (DES) administered orally to pigs can be detected by radioimmunoassay (RIA) analysis of kidney, liver, faeces, bile and urine from animals fed continuously to slaughter, but not in muscle, fat or plasma. If treated animals are fed on material not containing DES for 72 h prior to slaughter, then the levels of parent compound and metabolite in all products decrease to become not significantly greater than those in control animals. The gross metabolism of DES in pigs and bovines appears to be similar. 相似文献
37.
由主成分分析(PCA)可知任何一幅人脸图像都可以通过一组特征脸的线性加权来重构,PCA是最小均方误差意义下图像的最优表示,但是传统的PCA最终只通过比较加权系数的欧氏距离来进行识别,没有考虑残差。因此,提出非相似尺度的概念,将两个样本同时投影到相同向量上,在确定它们关系时既考虑投影系数,也考虑重构所产生的残差。两者的投影系数和残差相差越大,说明这两个样本越不相似。和保局投影(LPP)有所不同,非相似度保持投影算法不必预先设定近邻个数,它是利用非相似度的概念,创建非相似度散布矩阵,最终通过最大化目标函数获取最优子空间。在AR库和Feret库上的实验结果证明了该方法的有效性。 相似文献
38.
针对餐厨垃圾厌氧处理所产生的沼渣具有产量大、灰分质量分数高的特点,研究沼渣中无机灰分对其热解过程的影响. 通过热重分析和热裂解?气相色谱质谱联用技术(Py-GC/MS)分析沼渣热解动力学特性及其产物. 动力学分析结果表明,沼渣除灰后,失重速率显著提高,热解起始温度由180 ℃降至160 ℃. 除灰沼渣的总表观活化能比沼渣的略高,原因可能是除灰使沼渣内部孔隙增加,在促进挥发分析出的同时,削弱了部分组分在热解过程中的催化裂解作用. 产物分析结果表明,NaCl能够促进油相产物中烃类向酮类的转化,ZnCl2通过促进酸类的脱羧作用,使烃类质量分数提高至66.8%;Fe2O3和Al2O3使烃类物质的质量分数分别提高至66.8%和72.7%,CaO和MgO可以促进酸类脱羧生成酮,使产物中酮类的质量分数高达46.5%和39.4%. 相似文献
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40.
Crosslinking modification can effectively improve the water resistance of soy protein isolate (SPI) adhesive, but it often depends on petroleum-based reagents, violating the concept of green environmental protection. Here, inspired by the breaking and recombination of the disulfide bond in the perm process, a high-performance wood adhesive is prepared by incorporation of SPI (modified by sodium sulfite to cleave the disulfide bonds of protein chains) and feather keratin (FK, extracted from waste chicken feathers by breaking the disulfide bond) without using any other crosslinkers. The crosslinking reaction occurs by disulfide bonds derived from the sulfhydryl group of FK and SPI. Thus the wet shear strength of the SPI/FK-20 adhesive is improved from 0.57 to 1.18 MPa, an increment of 107%. This study provides a green strategy to prepare high-performance protein-based adhesive from the waste products-chicken feathers, which will contribute to the development of the environmentally friendly wood adhesive industry. 相似文献