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121.
《Food Control》2001,12(2):77-83
A steady state model for a fish meal indirect pilot plant rotary dryer with steam tubes is developed. The model is based on mass and energy balances and heat transfer constitutive equations. Simulated and experimental results are presented. The moisture condition of fish meal predicted by the model agrees satisfactorily with experimental values obtained in the pilot plant dryer within the range of operating conditions explored.  相似文献   
122.
《Journal of power sources》2001,94(2):163-168
The plasticized polymer electrolytes composed of poly(methyl methacrylate-co-Li maleate), lithium perchlorate, and ethylene carbonate as a plasticizer, were newly prepared. The ion conductivities of the plasticized polymer electrolytes based on the poly(methyl methacrylate-co-Li maleate) were found to be dependent on the ion content of the ionomer, poly(methyl methacrylate-co-Li maleate), in the polymer electrolyte, and the polymer electrolyte based on the ionomer with 8.5 mol% ion content showed the maximum ion conductivity.The interfacial resistance at the polymer electrolyte/lithium interface and the cationic transference number were also investigated as a function of the ion content of the ionomer in the polymer electrolyte. The interfacial resistances as well as the cationic transference numbers of the polymer electrolytes were found to be also dependent on the ion content of the ionomer in the polymer electrolyte. Ion aggregations in the ionomer seemed to significantly influence the electrochemical behavior of the polymer electrolytes based on the ionomer.  相似文献   
123.
利用新型铝锆偶联剂对纳米CaCO3进行表面改性,采用光谱学分析方法对铝锆偶联剂在纳米CaCO3表面的吸附特性进行探讨。通过透射电镜(TEM)、沉降体积、浊度测试等实验对纳米CaCO3的表面改性效果进行评价。红外光谱分析表明,铝锆偶联剂以化学键合的方式吸附在纳米CaCO3的表面。但X射线衍射分析证明,纳米CaCO3表面吸附层物质的引入并未对纳米CaCO3粉体的化学组成产生影响。经表面改性,纳米CaCO3的界面性质发生了很大变化,纳米CaCO3在水中的沉降体积减少,悬浮液浊度明显增大,说明纳米CaCO3在水中的分散性得到很大改善。  相似文献   
124.
表面活性剂对水性油墨胶体稳定性的影响   总被引:2,自引:0,他引:2  
对阳离子、阴离子、两性和非离子表面活性剂对水性油墨胶体稳定性的影响进行了探讨。结果表明:(1)在水性油墨胶体溶液中加入十六烷基三甲基溴化铵(CTAB)浓度为0.14 mmol/L时,Zeta电位由初始的-37.9 mV变为12.7 mV;当CTAB浓度为0.86 mmol/L时,Zeta电位上升到34.1 mV。pH对CTAB的作用效果有较大影响,当CTAB浓度为0.5 mmol/L时,将体系pH从初始值3.3调节至11.7,Zeta电位相应地从38.6 mV降至23.7 mV,炭黑粒子的平均粒径最大增加值达13 nm。(2)加入十二烷基磺酸钠(SDS)的浓度为1 mmol/L时,Zeta电位达到-38.2 mV,而炭黑粒子的平均粒径下降了2 nm。(3)加入椰油酰胺丙基氧化胺(CAPO)的浓度为0.01 mol/L时,Zeta电位在体系pH约为6.0时达到等电点;体系pH为3.2时,Zeta电位达到最大值28.5 mV,炭黑粒子平均粒径最大增加幅度为9 nm。(4)加入脂肪醇聚氧乙烯(7)醚(AEO-7)的浓度为0.1 mol/L时,体系Zeta电位从-37.9 mV变为-16.3 mV,炭黑粒子平均粒径从初始的154 nm增至240 nm。加入AEO-9得到与AEO-7相同的影响趋势。  相似文献   
125.
活性污泥法污水处理基准仿真模型的开发及进展   总被引:5,自引:0,他引:5  
国际水协(IWA)和欧盟科学技术合作组织(COST)合作开发了活性污泥污水处理基准仿真模型BSM1,主要目的是建立一个活性污泥处理过程自动控制方案的开发平台。BSM1定义了设备布局、仿真模型及参数、污水负荷、仿真步骤和仿真结果的评价标准。介绍了BSM1的应用现状及其改进模型(长期型1号基准仿真模型和2号基准仿真模型)的最新研究进展。  相似文献   
126.
Nowadays biosource-based materials have received revitalized interest for their ability to substitute for petrochemical-based materials. In this paper, we report a facile synthetic method of soybean oil-based polyfunctional acrylate (PFA) for UV-curable materials. Specifically, rapid and highly efficient side-chain functionalization of soybean oil was achieved via photoclick thiol-ene reaction, soybean oil-based polycarboxylic acid (PCA) was thus obtained. Next, by DCC (N,N′-dicyclohexylcarbodiimide) catalyzed esterification reaction with hydroxypropyl acrylate, polyfunctional acrylate (PFA) was synthesized at room temperature. Real-FTIR result indicated that almost 100% conversion of double-bond within vegetable oil was observed within 16.7 min, yielding the soybean oil-based polycarboxylic acid quantitatively. Furthermore, the structure of PFA was confirmed by 1H NMR and FTIR. Finally, the excellent UV-curing rate of PFA was revealed by real-FTIR.  相似文献   
127.
Aerogel is a class of material characterized by its high void content and extreme lightness. Different polymer/clay aerogels have been prepared by a simply freeze–thaw process from a suspension with poly(vinyl alcohol) (PVOH) and clay (Na+-MMT). Low density polymer/clay aerogels modified with flame retardant agents were prepared using a similar approach. The addition of flame retardant agents slightly increased the apparent density of the final composites whereas the compression properties were reduced due to the decrease in the polymer/clay interfacial bonding. An exception was the sample containing Al(OH)3 that exhibited higher modulus and stress at maximum deformation. Regarding thermal properties, the presence of ammonium polyphosphate (APP) or silica gel (SG) significantly slowed the rate of aerogel decomposition at the temperature range from 250 °C to 500 °C while the onset of polymer decomposition was not affected. Fire behavior was analyzed through cone calorimeter suggesting that either the presence of Al(OH)3 or APP reduced the heat release rate of PVOH/clay systems.  相似文献   
128.
Heat‐sealing properties are necessary for packaging materials. Soy protein isolate/polyvinyl alcohol (SPI/PVA) blend film is a biodegradable potential packaging material. We analyzed the effects of PVA content (0–20%), glycerol content (1–3%), and sealing temperature (180–230°C) on the heat‐sealing properties of SPI/PVA blend film. Results showed that SPI/PVA film obtained the desired sealing properties when the PVA content exceeded 15%. The sealing strength increased with the PVA content, reaching a maximum upon blending with 20% PVA and 1% glycerol at 220°C. The temperature at sealing strength was approximately twice that at 180°C. However, glycerol migrated to the surface and hindered the entanglement of macromolecular chains in the sealing interface, thereby resulting in reduction of seal strength. Glycerol vaporization at 204°C led to aesthetically unacceptable blistering in the sealing area. Therefore, the optimum sealing temperature of the blended film was ~200°C. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40308.  相似文献   
129.
The paper making waste liquor is a great water pollution source and much work has been done over the years to overcome this challenge. We present here a solution of black liquor used as dispersant of coal-water slurry (abbreviated as CWS) following chemical treatment. The treated black liquor (abbreviated as TBL) is used to prepare CWS for three bituminous coals, and the factors influencing its dispersing ability and the properties of CWS are investigated. The results show that the increasing sulfonating agent and formaldehyde dosage increase the sulfonic group content while reducing the molecular weight of TBL. The comparison with a naphthalene dispersant shows that TBL has a similar or better dispersing ability, and the large quantity of sulfonic groups engrafted in lignin molecules and the markedly increase of molecular weight are considered the key reason for the excellent performance of TBL. Moreover, the change of the molecular configuration from globular to flocculent in solution observed by TEM is also considered as an important reason for the excellent dispersing effect of TBL for CWS.  相似文献   
130.
羧甲基植物胶粉接枝共聚物的增强性能   总被引:1,自引:0,他引:1  
对植物胶粉接枝共聚物(CC-Na-g-PAM)在废报纸脱墨浆中的增强性能进行了研究。结果表明,CC-Na-g-PAM对纸浆具有很好的增强效果,优于使用阳离子淀粉和阳离子瓜尔胶。对于废报纸脱墨浆的最佳增强条件为:聚合物接枝率为452.0%,聚合物用量1.0%,抗张指数、撕裂指数和耐破指数可以分别提高30.43%、16.69%和28.66%。  相似文献   
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