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91.
十二烷基苯磺酸钠水溶液聚集性质的研究   总被引:8,自引:0,他引:8  
用滴体积法测出十二烷基苯磺酸钠(SDBS)稀水溶液的表面张力;然后求出其临界胶束浓度(CMC)。同时通过溶液的电导率、吸收光谱以及荧光光谱测定求出其CMC。这样测出的CMC值为1.2~1.6×10-3mol/L,与文献值相符。也研究了部分水解的聚丙烯酰胺(PHPAM)对SDBS聚集性质的影响;发现SDBS的CMC值随PHPAM的加人而减少并且PHPAM水溶液的粘度随SDBS的存在而急剧降低(类似盐效应)。这些方法与性质对强化采油(EOR)是重要的。  相似文献   
92.
以"面向对象的通用化工流程模拟软件ECSS"为平台,在其原来模块计算父类基础上设计了板式换热器模块计算子类,做出了板式换热器计算的数学模型,开发出了基于ECSS平台的板式换热器计算软件.可以对板片形式为等边三角形波纹板、不等边三角形波纹板、带褶三角形波纹板和不带褶三角形波纹板,流体的流道形式为1/1、1/2、1/3、1/4、2/2、3/3、4/4等流形的板式换热器进行计算.通过实例表明该软件具有较高的精确度,可以应用于实际的工程计算中.  相似文献   
93.
CeO2 particles confined within the pores of an SBA-15 mesoporous silica host were prepared by incipient wetness impregnation (IMP) and deposition precipitation (DP) methods. The materials were characterized by XRD, N2-adsorption and temperature programmed reduction (TPR) to evaluate the structure, texture, and redox properties. The preparation procedure had significant impact on the assembling mode of CeO2 inside the SBA-15 mesopores. A high dispersion of CeO2 particles was achieved via DP, whereas the dispersion of CeO2 prepared by IMP was found to be inhomogeneous and CeO2 partially blocked the pores. The CO conversion in the water-gas-shift reaction was enhanced over 1 wt% Pt supported on CeO2-modified SBA-15 obtained by DP.  相似文献   
94.
近些年,在高校校园数字化建设的逐步推进下,信息化建设取得了前所未有的进步,与此同时,高校的网络安全问题也变得日益突出。如何更好的保证高校网络安全运行,保障高校的基本网络需求,已经成为了当前高校网络研究和建设中需要重点关注的问题。为此,本文中笔者将结合自身的经验对高校校园网络的特点进行分析,从而得到其中存在的主要问题,并对提高高校网络安全的对策进行了一些阐述,以期能够更好地促进高校网络安全的发展和进步,为业内的其他研究提供借鉴和参考。  相似文献   
95.
A new kind of blend film was made by mixing the solutions of collagen, konjac glucommnnan (KGM), and sodium alginate. The structure of the blend film was characterized by FTIR, XRD, atomic absorption spectrophotometer, and SEM, respectively. The effects of weight ratio between the polymers on light transmittance, tensile strength, elongation at break, water permeability, and water absorption of the film were studied. The results showed that there were strong interactions and good compatibility between collagen, KGM, and sodium alginate in the film. The film possesses good mechanical properties. Therefore, it can be applied in biomedicine as a new type of biomaterial. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   
96.
Induced resistance in cotton (Gossypium hirsutum) foliage and squares to herbivory by Helicoverpa zea (Lepidoptera: Noctuidae) is reported in this study. Induced resistance was indicated by decreased larval growth when larvae fed on previously damaged foliage or squares compared to the controls. Herbivory caused a significant decline in host nutritional quality as shown by a reduction in protein and most amino acids in both foliage and squares. Peroxidase, ascorbate oxidase, and diamine oxidase activities increased in both damaged foliage and squares, whereas levels of the nutritional antioxidant, ascorbate, were depressed after larval feeding. Larval feeding also markedly enhanced lipoxygenase activity and lipid peroxides in square tissues. Moreover, feeding damage altered the quantitative levels of phenolic compounds in foliage and squares. These results indicate a significant shift in the oxidative status of cotton plants following herbivory as indicated by increased oxidative enzyme activity, decreased levels of the nutritional antioxidant ascorbate, and increased levels of phenolic prooxidants (i.e., chlorogenic acid) and lipid peroxides.  相似文献   
97.
以缙云天然丝光沸石为载体,考察了载体预处理、不同活性组分、负载量等因素对氨、吡啶、二乙胺吸附容量的影响。结果表明,负载CuSO_4对氨的吸附容量明显提高,具有物理吸附和化学吸附双重功能,但吡啶、二乙胺略有下降。随着焙烧温度的提高,其对氨的吸附能力也提高,水份的存在对氨的吸附容量影响不大。  相似文献   
98.
Minimum spouting velocities in conical spouted beds have been obtained from pressure drops versus the superficial gas velocity curves, based on both increasing and decreasing the superficial gas velocity. It has been shown that the minimum spouting velocity from decreasing the superficial gas velocity is lower than from increasing the superficial gas velocity in most cases. This phenomenon is similar to that in conventional spouted beds and different from the early works. The experimental results also showed that there isn't significant difference in the pressure drop and Ums under identical operating conditions between semi‐circular and circular conical spouted beds, and the same Ums can be obtained from absolute pressure drops at any position above the gas inlet. The Ums is found to increase with increasing the cone angle and static bed height, as well as the gas inlet diameter to a less extent.  相似文献   
99.
宽严相济是我国现阶段的刑事政策,恢复性司法的恢复性正义理念与此相契合;恢复性司法具有弥补受害人所受伤害、矫正犯罪行为、平复被破坏的社会关系等功能;在其本土化构造的过程中,必须结合我国国情对其进行规制和完善,以达到法律效果与社会效果的统一,从而促进社会和谐。  相似文献   
100.
A measurement system has been developed based on high-precision printed probes in printed circuit board (PCB) and steep rising-time probe adapters,which can be applied to study the expansion uniformity of armature in a helical magnetic flux compression generator (HFCG).The influences of wall thickness and initiation position on the expansion uniformity of armature in HFCG were experimentally investigated.The results show that the armature with thinner wall thickness will easily rupture due to the high pressure of detonation products inside,the armature with larger wall thickness will easily crack due to the tensile stress on the outer surface of the wall,the influence of the end effect on the expansion uniformity can be ignored if the distance between the first group of probe and the initiation point is more than 3 times the armature diameter.  相似文献   
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