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Hierarchical porous carbon derived from one-step self-activation of zinc gluconate for symmetric supercapacitors with high energy density

《化学科学与工程前沿（英文）》 2023年 第17卷 第4期   页码 387-394 doi: 10.1007/s11705-022-2250-3

摘要： Porous carbons with high specific area surfaces are promising electrode materials for supercapacitors. However, their production usually involves complex, time-consuming, and corrosive processes. Hence, a straightforward and effective strategy is presented for producing highly porous carbons via a self-activation procedure utilizing zinc gluconate as the precursor. The volatile nature of zinc at high temperatures gives the carbons a large specific surface area and an abundance of mesopores, which avoids the use of additional activators and templates. Consequently, the obtained porous carbon electrode delivers a satisfactory specific capacitance and outstanding cycling durability of 90.9% after 50000 cycles at 10 A∙g–1. The symmetric supercapacitors assembled by the optimal electrodes exhibit an acceptable rate capability and a distinguished cycling stability in both aqueous and ionic liquid electrolytes. Accordingly, capacitance retention rates of 77.8% and 85.7% are achieved after 50000 cycles in aqueous alkaline electrolyte and 10000 cycles in ionic liquid electrolyte. Moreover, the symmetric supercapacitors deliver high energy/power densities of 49.8 W∙h∙kg–1/2477.8 W∙kg–1 in the Et4NBF4 electrolyte, outperforming the majority of previously reported porous carbon-based symmetric supercapacitors in ionic liquid electrolytes.

关键词： self-activation     zinc organic salts     abundant mesopores     symmetric supercapacitor     liquid electrolyte    

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Hierarchical ZSM-5 zeolite with radial mesopores: Preparation, formation mechanism and application for

Darui Wang, Hongmin Sun, Wei Liu, Zhenhao Shen, Weimin Yang

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 248-257 doi: 10.1007/s11705-019-1853-9

摘要： Hierarchical ZSM-5 zeolite with radial mesopores is controllably synthesized using piperidine in a NaOH solution. The piperidine molecules enter the zeolite micropores and protect the zeolite framework from extensive desilication. The areas containing fewer aluminum atoms contain fewer piperidine protectant molecules and so they dissolve first. Small amounts of mesopores are then gradually generated in areas with more aluminum atoms and more piperidine protectant. In this manner, radial mesopores are formed in the ZSM-5 zeolite with a maximal preservation of the micropores and active sites. The optimal hierarchical ZSM-5 zeolite, prepared with a molar ratio of piperidine to zeolite of 0.03, had a mesopore surface area of 136 m ·g and a solid yield of 80%. The incorporation of the radial mesopores results in micropores that are interconnected which shortened the average diffusion path length. Compared to the parent zeolite, the hierarchical ZSM-5 zeolite possesses more accessible acid sites and has a higher catalytic activity and a longer lifetime for the alkylation of benzene.

关键词： hierarchical ZSM-5 zeolite     protective desilication     piperidine     radial mesopores     benzene alkylation    

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OVEREXPRESSION OF PTRLEA7, A LATE EMBRYOGENESIS ABUNDANT FAMILY GENE FROM PONCIRUS TRIFOLIATA, CONFERS

《农业科学与工程前沿（英文）》 2021年 第8卷 第2期

摘要：

Late embryogenesis abundant (LEA) genes encode highly hydrophilic proteins that are essential in abiotic stress responses. However, most LEA genes in higher plants have not yet been investigated. This study identified an LEA family gene (PtrLEA7) from Poncirus trifoliata and studied its function in drought tolerance. The full-length coding sequence of PtrLEA7 was 420 bp encoding a protein of 139 amino acids. Phylogenetic analysis shows that PtrLEA7 protein belongs to the LEA_4 subfamily. Expression profiling by qPCR found that PtrLEA7 was strongly induced by dehydration, cold and ABA treatments, and slightly induced by salt stress. Subcellular localization reveals that PtrLEA7 protein was located in both cytoplasm and nucleus. To investigate its function, transgenic plants of both tobacco and Poncirus trifoliata overexpressing PtrLEA7 were obtained. Stress tolerance assays show that overexpression lines had enhanced dehydration and drought tolerance compared with wild type plants, indicating that PtrLEA7 positively regulates drought tolerance. In addition, transgenic plants had much higher expression levels of three antioxidant enzyme genes (CAT, SOD and POD) and significantly increased catalase enzyme activity, accompanied by reduced reactive oxygen species accumulation in comparison with wild type plants. Collectively, this study demonstrates that PtrLEA7 can confer enhanced drought tolerance partially via enhancing antioxidant capacity.

 

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Distinct community assembly processes underlie significant spatiotemporal dynamics of abundant and rare

《环境科学与工程前沿（英文）》 2022年 第16卷 第6期 doi: 10.1007/s11783-021-1513-4

摘要：

• Season and landform influenced spatiotemporal patterns of abundant and rare taxa.

关键词： Rare taxa     Biogeography     Community assembly     Bacterioplankton     The Yangtze River    

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OVEREXPRESSION OF

Tonglu WEI, Dalong GUO, Jihong LIU

《农业科学与工程前沿（英文）》   页码 236-246 doi: 10.15302/J-FASE-2020368

摘要： Late embryogenesis abundant (LEA) genes encode highly hydrophilic proteins that are essential in abiotic stress responses. However, most LEA genes in higher plants have not yet been investigated. This study identified an LEA family gene (PtrLEA7) from Poncirus trifoliata and studied its function in drought tolerance. The full-length coding sequence of PtrLEA7 was 420 bp encoding a protein of 139 amino acids. Phylogenetic analysis shows that PtrLEA7 protein belongs to the LEA_4 subfamily. Expression profiling by qPCR found that PtrLEA7 was strongly induced by dehydration, cold and ABA treatments, and slightly induced by salt stress. Subcellular localization reveals that PtrLEA7 protein was located in both cytoplasm and nucleus. To investigate its function, transgenic plants of both tobacco and Poncirus trifoliata overexpressing PtrLEA7 were obtained. Stress tolerance assays show that overexpression lines had enhanced dehydration and drought tolerance compared with wild type plants, indicating that PtrLEA7 positively regulates drought tolerance. In addition, transgenic plants had much higher expression levels of three antioxidant enzyme genes (CAT, SOD and POD) and significantly increased catalase enzyme activity, accompanied by reduced reactive oxygen species accumulation in comparison with wild type plants. Collectively, this study demonstrates that PtrLEA7 can confer enhanced drought tolerance partially via enhancing antioxidant capacity.

关键词： abiotic stress     antioxidant     drought     late embryogenesis abundant     Poncirus trifoliata    

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Alkaline modification of ZSM-5 catalysts for methanol aromatization: The effect of the alkaline concentration

Zhenhao Wei,Tengfei Xia,Minghui Liu,Qingsheng Cao,Yarong Xu,Kake Zhu,Xuedong Zhu

《化学科学与工程前沿（英文）》 2015年 第9卷 第4期   页码 450-460 doi: 10.1007/s11705-015-1542-2

摘要： The effects of alkaline treatment on the physical properties of ZSM-5 catalysts and on their activities for methanol to aromatics conversion have been investigated. A mild alkaline treatment (0.2 and 0.3 mol/L NaOH) created mesopores in the parent zeolite with no obvious effect on acidity. The presence of mesopores gives the catalyst a longer lifetime and higher selectivity for aromatics. Treatment with 0.4 mol/L NaOH decreased the number of Brønsted acid sites due to dealumination and desilication, which resulted in a lower deactivation rate. In addition, more mesopores were produced than with the mild alkaline treatment. As a result, the lifetime of the sample treated with 0.4 mol/L NaOH was almost five times that of the parent ZSM-5. Treatment with a higher alkaline concentration (0.5 mol/L) greatly reduced the number of Brønsted acid sites and the number of micropores resulting in incomplete methanol conversion. When the alkaline-treated catalysts were washed with acid, some of the porosity was restored and a slight increase in selectivity for aromatics was obtained.

关键词： aromatics     ZSM-5     alkaline treatment     dealumination     desilication     mesopores     methanol    

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Life cycle analysis and choice of natural gas-based automotive alternative fuels in Chongqing Municipality, China

WU Rui, LI Guangyi, ZHANG Zongyi, REN Yulong, HAN Weijian

《环境科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 292-298 doi: 10.1007/s11783-007-0049-6

摘要： Road transport produces significant amounts of emissions by using crude oil as the primary energy source. A reduction of emissions can be achieved by implementing alternative fuel chains. The objective of this study is to carry out an economic, environmental and energy (EEE) life cycle study on natural gas-based automotive fuels with conventional gasoline in an abundant region of China. A set of indices of four fuels/vehicle systems on the basis of life cycle are assessed in terms of impact of EEE, in which natural gas produces compressed natural gas (CNG), methanol, dimethylether (DME) and Fischer Tropsch diesel (FTD). The study included fuel production, vehicle production, vehicle operation, infrastructure and vehicle end of life as a system for each fuel/vehicle system. A generic gasoline fueled car is used as a baseline. Data have been reviewed and modified based on the best knowledge available to Chongqing local sources. Results indicated that when we could not change electric and hydrogen fuel cell vehicles into commercial vehicles on a large scale, direct use of CNG in a dedicated or bi-fuel vehicle is an economical choice for the region which is most energy efficient and more environmental friendly. The study can be used to support decisions on how natural gas resources can best be utilized as a fuel/energy resource for automobiles, and what issues need to be resolved in Chongqing. The models and approaches for this study can be applied to other regions of China as long as all the assumptions are well defined and modified to find a substitute automotive energy source and establish an energy policy in a specific region.

关键词： dedicated     primary     economic     alternative     abundant    

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Organosilane surfactant-assisted synthesis of mesoporous SSZ-39 zeolite with enhanced catalytic performance in the methanol-to-olefins reaction

Hao Xu, Chi Lei, Qinming Wu, Qiuyan Zhu, Xiangju Meng, Daniel Dai, Stefan Maurer, Andrei-Nicolae Parvulescu, Ulrich Müller, Fengshou Xiao

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 267-274 doi: 10.1007/s11705-019-1845-9

摘要： SSZ-39 zeolite with AEI framework structure is a good catalyst candidate for the methanol-to-olefins (MTO) reaction. However, the diffusion limitation and coke formation often results in fast deactivation of the SSZ-39 zeolite catalyst. One solution for this challenge is to introduce mesoporosity in the SSZ-39 zeolite. Herein, we report the synthesis of mesoporous SSZ-39 zeolite using an organosilane surfactant, , -dimethyl- -(3-(trimethoxysilyl)propyl)octan-1-aminium chloride, as a mesopore template and , -dimethyl- -2,6-dimethylpiperidinium as a micropore template. The obtained zeolites were characterized by X-ray diffraction, N sorption, scanning electron microscopy, temperature programmed desorption of ammonia, and magic angle spinning nuclear magnetic resonance of Al. The results show that the mesoporous SSZ-39 zeolite has high crystallinity, meso/microporosity, high surface area, cuboid morphology, and abundant acidic sites. More importantly, this mesoporous SSZ-39 zeolite exhibits enhanced catalyst lifetime in the MTO reaction due to the presence of mesoporosity for fast mass transfer, compared with a conventional SSZ-39 zeolite without mesoporosity.

关键词： SSZ-39 zeolite     mesopores     organosilane surfactant     MTO reaction     soft template     mass transfer    

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标题 作者 时间 类型 操作

Hierarchical porous carbon derived from one-step self-activation of zinc gluconate for symmetric supercapacitors with high energy density

期刊论文

Hierarchical ZSM-5 zeolite with radial mesopores: Preparation, formation mechanism and application for

Darui Wang, Hongmin Sun, Wei Liu, Zhenhao Shen, Weimin Yang

期刊论文

OVEREXPRESSION OF PTRLEA7, A LATE EMBRYOGENESIS ABUNDANT FAMILY GENE FROM PONCIRUS TRIFOLIATA, CONFERS

期刊论文

Distinct community assembly processes underlie significant spatiotemporal dynamics of abundant and rare

期刊论文

OVEREXPRESSION OF

Tonglu WEI, Dalong GUO, Jihong LIU

期刊论文

Alkaline modification of ZSM-5 catalysts for methanol aromatization: The effect of the alkaline concentration

Zhenhao Wei,Tengfei Xia,Minghui Liu,Qingsheng Cao,Yarong Xu,Kake Zhu,Xuedong Zhu

期刊论文

Life cycle analysis and choice of natural gas-based automotive alternative fuels in Chongqing Municipality, China

WU Rui, LI Guangyi, ZHANG Zongyi, REN Yulong, HAN Weijian

期刊论文

Organosilane surfactant-assisted synthesis of mesoporous SSZ-39 zeolite with enhanced catalytic performance in the methanol-to-olefins reaction

Hao Xu, Chi Lei, Qinming Wu, Qiuyan Zhu, Xiangju Meng, Daniel Dai, Stefan Maurer, Andrei-Nicolae Parvulescu, Ulrich Müller, Fengshou Xiao

期刊论文