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91.
Chunfeng Song Muhammad Mujahid Run Li Siraj Ahmad Qingling Liu Bing Zhang Yutaka Kitamura 《Greenhouse Gases: Science and Technology》2020,10(2):408-420
Mixed matrix membranes (MMMs) played a promising role in gas separation. However, the trade‐off between permeability and selectivity is still a challenge for its commercial application. Rational design of the inorganic filler, compatibility of filler with the polymer, and dispersion of filler into the polymer have a significant influence on the morphology and separation performance of a membrane. In this study, in order to produce defect‐free flat sheet MMMs, two different solvents (N‐methyl‐2‐pyrrolidone and ethanol/water) were investigated to maximize the dispersion of filler (multi‐walled carbon nanotubes, MWCNTs) in Pebax. The prepared membranes were characterized by scanning electron microscope (SEM), Fourier‐transform infrared spectroscopy (FTIR), and X‐ray diffraction (XRD) analysis. CO2/N2 permeation tests were undertaken to investigate the solvent effect on membrane permeation properties. The result showed that membranes fabricated with higher molar volume solvent were more efficient for CO2 separation. Considering the trade‐off between different parameters (molar volume of solvent, fraction‐free volume, crystallinity of membranes), the permeability and CO2/N2 selectivity of Pebax/MWCNTs MMMs was optimized to 405 Barrer and 51, respectively. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd. 相似文献
92.
本文阐述了大气污染综合整治规划软件在北票市的实际应用，以北票市大气污染综合整治为实例，建立了大气污染综合整治计算机处理系统，取得了满意的效果． 相似文献
93.
本文针对当前社会对税务代理人员的旺盛需求,结合我校现有的教学资源,对在我校开设税务代理专业的可行性进行了研究与分析。 相似文献
94.
95.
This study investigated a combined low-thermal and CaO2 pretreatment to enhance the volatile fatty acid (VFA) production from waste activated sludge (WAS). The fermentative product was added to a sequencing batch reactor (SBR) as an external carbon source to enhance nitrogen removal. The results showed that the combined pretreatment improved WAS solubilization, releasing more biodegradable substrates, such as proteins and polysaccharides, from TB-EPS to LB-EPS and S-EPS. The maximum VFA production of 3529 ± 188 mg COD/L was obtained in the combined pretreatment (0.2 g CaO2/g VS + 70 °C for 60 min), which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test, respectively. Consequently, when the fermentative liquid was added as an external denitrification carbon source, the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China. 相似文献
96.
The moisture from skin sweat and atmospheric water affects the thermal protective performance provided by multilayer protective clothing. Four levels of moisture content were selected to evaluate the impact of moisture on thermal protection under dry (thermal radiation) and wet (thermal radiation and low-pressure steam) heat exposure. Also, the role of moisture and its relationship with exposure time were analyzed based on skin heat flux and Henriques integral value. The addition of moisture to a fabric system was found to result in differences in second-degree and third-degree skin burn times. When moisture is added to a fabric system, it both acts as a thermal conductor to present a negative effect and provides a positive effect owing to thermal storage of water and evaporative heat loss. The positive or negative effects of moisture are mainly dependent on the thermal exposure time, the moisture content and the presence of hot steam. 相似文献
97.
为评价一种进口多功能撇油器应对渤海冬季溢油的能力,试验分别对刷式、盘式、鼓式三种撇油头在无冰和有冰(冰密集度约5成)条件下进行收油速率测试。试验以100 L油品为基数,测出在各种组合条件下回收油品所需要的时间,并把鼓式撇油头在有冰条件下的泵速提高,再进行试验。结果发现三种撇油方式的回收速率不仅与撇油头类型有关,同时也取决于是否有冰;在有冰条件下,三种撇油头收油效果都受到影响,其中盘式撇油器受影响最大,无法回收溢油;在有冰条件下加大鼓式撇油头泵速会提高总回收速率,但含水率同时提高;对凝固原油,撇油器无能为力。试验结果对正确评估三种类型的撇油头在两种情况下的收油效果和相关单位应具备的清除溢油能力,以及今后引进设备提高应急能力将起到借鉴作用。 相似文献
98.
论交通结构调整与交通可持续发展 总被引：3，自引：0，他引：3
从社会经济可持续发展理论出发,分析了交通发展对资源和环境的影响,阐述了交通可持续发展的内涵,针对当前交通发展所面临的问题,提出了当前要加快交通结构调整的方针,并指明了要做好的相关工作,以促进交通可持续发展。 相似文献
99.
Min Hoan Moon Jeong Yeon Cho Eun Jung Park Jee Yeon Min Jeong-Ah Kim Sung Il Jung Mi Jin Song 《黑龙江环境通报》2007,27(2):158-163
100.