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991.
Chenxu Geng Yuxiu Sun Zhengqing Zhang Zhihua Qiao Chongli Zhong 《American Institute of Chemical Engineers》2023,69(5):e18025
Mixed matrix metal–organic framework (MOF) membranes show excellent application prospects in gas separation. However, their stability in various practical application scenarios is poor, especially under humid conditions. Herein, we encapsulated a hydrophobic ionic liquid (IL) into the cavity of MOFs, which effectively mitigated the competition between H2O and CO2 in humid gas mixtures, leading to stable and high-performance gas separation. For this reason, the resulting membranes using polymer of intrinsic miroporosity-1 (PIM-1) as a polymer matrix show good CO2/N2 separation performance and long-term test stability under humid environment. In particular, the 20 wt% IL-UiO/PIM-1 shows a high permeability of 13,778 Barrer and competitive CO2/N2 separation factor of ~35.2, transcending the latest upper bound. Besides, the according membrane module exhibits slightly decreased CO2 permeability and selectivity, promoting the application of self-supporting membranes. This work provides a reliable strategy for the rational design of MOF-based hybrid membranes under extreme conditions. 相似文献
992.
Qiao Xue Ruikun Wang Shu Meng Shiteng Tan Zhenghui Zhao Qianqian Yin Huan Li 《加拿大化工杂志》2023,101(10):5519-5529
Carbonaceous microspheres formed through heterogeneous polymerization reactions during hydrothermal carbonization of biomass showed a considerable effect on the mass yield and physicochemical properties of hydrochar. In exploring the growth mechanism of carbonaceous microspheres, the heterogeneous polymerization reaction of four typical organic components (5-hydroxymethylfurfural, furfural, phenol, and p-xylene) with the surficial functional groups of carbonaceous microspheres was investigated using density functional theory (DFT). Nucleophilic addition and dehydration are the main forms of polymerization reactions, and the former shows a lower reaction energy barrier than the latter by 100 kJ/mol, indicating that the nucleophilic addition reactions likely occur compared to dehydration reactions. And phenol likely promotes the growth of microspheres. In addition, the surficial furan ring structure of carbonaceous microspheres opened through ring opening, hydrogen atom transfer, and molecular space structure conversion in sequence. Among these reaction steps, the furan ring opening through hydration was the rate-limiting reaction step, which showed the highest energy barrier with a value of 394.51 kJ/mol. However, the ring opening of furan rings could form more active sites, such as carbonyl groups, for subsequent polymerization reactions, indicating an increased potential for further reactions with aqueous-phase organic components. 相似文献
993.
High-quality data play a paramount role in monitoring, control, and prediction of wastewater treatment process (WWTP) and can effectively ensure the efficient and stable operation of system. Missing values seriously degrade the accuracy, reliability and completeness of the data quality due to network collapses, connection errors and data transformation failures. In these cases, it is infeasible to recover missing data depending on the correlation with other variables. To tackle this issue, a univariate imputation method (UIM) is proposed for WWTP integrating decomposition method and imputation algorithms. First, the seasonal-trend decomposition based on loess method is utilized to decompose the original time series into the seasonal, trend and remainder components to deal with the nonstationary characteristics of WWTP data. Second, the support vector regression is used to approximate the nonlinearity of the trend and remainder components respectively to provide estimates of its missing values. A self-similarity decomposition is conducted to fill the seasonal component based on its periodic pattern. Third, all the imputed results are merged to obtain the imputation result. Finally, six time series of WWTP are used to evaluate the imputation performance of the proposed UIM by comparing with existing seven methods based on two indicators. The experimental results illustrate that the proposed UIM is effective for WWTP time series under different missing ratios. Therefore, the proposed UIM is a promising method to impute WWTP time series. 相似文献
994.
995.
对德国SKET、HERBORN,意大利Redaelli、GCR、EEI等设备制造公司及有关金属制品厂进行考察,介绍其产品性能及生产线特点。 相似文献
996.
997.
随着通信技术的快速发展,各领域对高速总线的要求越来越高.在整个通信网络中,1394b的高效率有着至关重要的作用.对整个1394b总线网络提出了准确性、实时性和可靠性等约束,保证了1394b总线的传输特性;对1394b总线网络中传输的异步流数据包和STOF数据包进行包格式设计,确保了1394b总线网络传输的准确性;搭建了一个单总线四节点的1394b总线网络作为测试验证平台,并对该总线通信进行了测试与验证.经过测试分析和测试总结,本通信机制下整个通信网络的高效性能都达了到预期目标. 相似文献
998.
探讨低温等离子体预处理和壳聚糖水性聚氨酯共混整理对棉织物白度、折皱回复性和透湿性的影响。分析了共混乳液成膜后的红外光谱图,将水性聚氨酯与壳聚糖以不同比例共混后整理到经等离子体预处理与未经等离子体预处理的棉织物上,测试了各织物的白度、折皱回复角和透湿率。结果发现:共混膜同时具有聚氨酯与壳聚糖的特征基团并产生新的特征峰;随着整理液中壳聚糖含量的增加,织物白度下降,折皱回复角下降,透湿率增加;采用等离子体处理后织物白度增加,折皱回复角下降,透湿率增加。认为壳聚糖水性聚氨酯共混比例和等离子体预处理均对整理出的棉织物性能有影响。 相似文献
999.
摘要:目的:对我国主要小龙虾产区不同养殖方式(池塘精养、虾蟹混养、稻田套养及藕虾套养)及小龙虾不同部位(肌肉、内脏、头壳及背壳)中药物与个人护理品(pharmaceuticals and personal care products, PPCPs)的暴露种类进行筛查,并对其蓄积规律进行研究。方法:利用轨道阱高分辨质谱通过非靶向筛查技术对长江中下游小龙虾样品中PPCPs的种类进行筛查和鉴定。结果:本次收集的样品中共检测到并筛选出了30种化合物,其中麻醉药类物质共7种,镇痛药类7种,消炎类药物8种,其余为非常规药品或环境危害物(肠道用药、清洁剂等),共8种,不同养殖模式的小龙虾体内筛选出的PPCPs种类数量排名为:池塘精养虾=虾蟹混养>稻田套养虾>藕虾套养虾,小龙虾各部位的PPCPs种类数量排名为:肌肉>背壳>内脏>头壳,可食用部位(虾肉、虾黄)多于外壳部位。结论:不同养殖模式的小龙虾样品中PPCPs的筛选结果在数量上存在一定的差异,但组成规律上较为相似,具体为:都以消炎药为主,其次为麻醉药和镇痛剂,最值得关注的物质为氯甲西泮。 相似文献
1000.