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101.
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介绍了为提高氯气质量,降低含水量及酸雾夹带量而采取的技术改进措施,包括改进干燥剂的加入方式。改进氯气洗涤方式以及增设两级串联防雾等措施。通过改进实现了氯气干燥系统的长周期、安全稳定运行。 相似文献
103.
Self‐assembled centimetre‐sized rods obtained in the oxidation of o‐phenylenediamine and aniline 下载免费PDF全文
Venkata Sai Sriram Mosali Graham A Bowmaker Melvin Gerard Paul A Kilmartin Jadranka Travas‐Sejdic Zoran D Zujovic 《Polymer International》2015,64(9):1135-1141
Morphologically well‐defined rods of approximately 1 cm in length are effectively and economically obtained by mixing ortho‐phenylenediamine (30 mmol L?1) with ammonium persulfate (12.5 mmol L?1) in an acidic solution (0.37 mol L?1 HCl) at room temperature with and without the presence of 50 mmol L?1 aniline. These self‐assembled, morphologically uniform products can be potentially scaled up and used as morphological templates to fabricate well‐defined structures of other materials such as conducting polymers. The products were characterized using Raman, UV‐visible, high‐resolution NMR (1H and 13C) and mass spectroscopies, X‐ray diffraction, scanning electron microscopy and elemental analysis. Apart from certain differences in visual appearance and in X‐ray diffractograms, other analytical data suggest that there are no structural changes upon addition of aniline into the reaction mixture. NMR and mass spectra imply that all syntheses carried out either with or without aniline result in a mixture of two products, attributed to 2,3‐phenazinediamine and 3‐aminophenazin‐2‐ol. A formation mechanism based on hydrogen bonding and π–π stacking has been proposed. © 2015 Society of Chemical Industry 相似文献
104.
为解决糠醛生产过程中收率低和污染严重等问题,提出使用氯化铁/氯化钠复合催化木糖经反应萃取生产糠醛的新工艺。首先研究了催化剂用量对反应过程的影响,得到了最优的催化剂添加量。然后以获得降解过程中较高的木糖转化率和糠醛收率为目的,通过响应曲面法研究了反应温度(170—210℃)、溶剂比(体积比1—5)、反应时间(15—75 min)对木糖降解过程的影响,并建立了木糖转化率和糠醛收率的二次多项式模型。由响应面分析和方程模型优化可以得到木糖降解过程的最优降解条件:反应温度190℃,溶剂比4,反应时间48 min,此时木糖转化率为93.1%,糠醛收率为75.6%。在最优降解条件下的实验验证结果与模型预测值非常接近,说明模型是适用的。 相似文献
105.
着色剂对PET树脂特性粘度的影响 总被引:1,自引:0,他引:1
依据色素分子的性质,将着色剂进行了分类,并以此为基础讨论不同着色剂对聚酯特性粘度的影响,通过Mark-Houwink公式,推导了着色剂的加入与聚酯特性粘度之间的关系,发现小分子染料会使聚酯特性粘度迅速下降,聚合染料基本不影响聚酯的特性粘度,而熔融活性着色剂在低浓度范围内对聚酯起着明显的增粘作用,不仅可提高着色牢度,还可以抵消由于热加工而引起的聚酯的热降解。 相似文献
106.
Electrodeionization (EDI) of cesium from cesium-sorbed ammonium molybdophosphate-polyacrylonitrile (AMP-PAN) was investigated by passing eluant through the packed bed of ion-exchange resin in an electrodialysis cell. The deionized cesium from the packed bed was recovered in catholyte by migration and in the eluant by convection. Recovery percentage of Cs by migration increased while the recovery by convection decreased with increase in current density from 20 to 40 mA/cm2. Increased eluant concentration resulted in low migration percentage of cesium. Increased catholyte concentration had a negligible effect on total recovery. Apparent diffusion coefficients evaluated using the Nernst–Plank relation increased with increase in current density and catholyte concentration while a decreasing trend was observed with increase in eluant concentration. 相似文献
107.
Fatih Kalkan Sai Kranthi Vanga Ramesh Murugesan Valerie Orsat Vijaya Raghavan 《Drying Technology》2017,35(5):527-533
This study was performed to investigate the influence of air inlet temperature (AIT) on the microencapsulation of hazelnut oil by spray drying. Encapsulated powders were analyzed for moisture content, powder yield, surface oil, encapsulation efficiency (EE), bulk density, and particle morphology. The obtained results demonstrated that moisture content, surface oil, and bulk density decreased by 37.8, 27.5, and 33%, respectively as AIT increased from 140 to 220°C. However, powder yield and encapsulation efficiency increased considerably with the rise in AIT. Higher EEs of about 75–80% were observed in this study. 相似文献
108.
Stearic Acid Modified Stearyl Alcohol Oleogel: Analysis of the Thermal,Mechanical and Drug Release Properties 下载免费PDF全文
Indu?Yadav Uvanesh?Kasiviswanathan Chandan?Soni Suprio?R.?Paul Suraj?K.?Nayak Sai?S.?Sagiri Arfat?Anis Kunal?PalEmail author 《Journal of surfactants and detergents》2017,20(4):851-861
The present study delineates the effect of stearic acid on the properties of stearyl alcohol oleogel. Herein, a series of oleogels were prepared by mixing different proportions of fatty alcohol (Stearyl alcohol; gelator) and fatty acid (stearic acid; co‐gelator). The characterization of the oleogels was done by thermal, macro‐scale stress relaxation, drug release, and antimicrobial studies. The oleogels were formed by the self‐assembly of stearyl alcohol/stearic acid. Thermal studies indicated that the stearic acid alters the crystal morphology, polymorphic transition and rate of crystallization of stearyl alcohol. The firmness of the oleogels with higher stearic proportion was better, which was due to the formation of a rigid network structure of stearyl alcohol in the presence of stearic acid. The release of ciprofloxacin hydrochloride, model drug, from the oleogels was better from the oleogels with higher stearic acid content. The release of the drug from the oleogels was Fickian diffusion‐mediated; except the oleogel with the highest stearic acid proportion. The antimicrobial study showed that the drug loaded oleogels were able to resist the growth of Escherichia coli, model microbe. 相似文献
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