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新疆尾闾盐湖滨岸盐碱土中碳酸盐的固碳效应及影响因素 预览
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作者 张芳 熊黑钢 张兆永 《农业工程学报》 EI CAS CSCD 北大核心 2019年第2期122-127,共6页
土壤碳酸盐对现代大气CO2的截存与土壤中的硅酸盐矿物组成、盐基元素供给、有机碳含量等因子密切相关。该文结合土壤理化性质和碳同位素分馏特性,以新疆艾比湖为例,探讨了干旱区尾闾盐湖滨岸盐碱土中碳酸盐的固碳效应和影响因素,研究结... 土壤碳酸盐对现代大气CO2的截存与土壤中的硅酸盐矿物组成、盐基元素供给、有机碳含量等因子密切相关。该文结合土壤理化性质和碳同位素分馏特性,以新疆艾比湖为例,探讨了干旱区尾闾盐湖滨岸盐碱土中碳酸盐的固碳效应和影响因素,研究结果表明:1)土壤碳酸盐是干旱区最重要的碳库,艾比湖滨岸土壤碳酸盐的平均碳密度是有机碳的4.05倍;2)艾比湖滨岸盐碱土中的δ^13CSCC介于-7.9‰~0.3‰之间,δ^13CSCC与HCO3^-存在良好的线性负相关关系,决定系数高达0.6699,大气碳以重碳酸盐形式存在是次生碳酸盐淀积的关键环节之一;3)土壤δ^13CSCC值与硅酸盐矿物阳起石、绿泥石、伊利石存在着良好的线性负相关关系,δ^13CSCC值随着富Ca、Mg、Fe矿物的含量增加明显向负向漂移;4)土壤中有机碳含量越高,生物风化过程越强烈时,δ^13CSCC负向漂移越大,土壤碳酸盐截存较多大气中的轻碳;当土壤含盐量超过一定程度时,有机过程受到抑制,土壤碳酸盐则截存较多大气中的重碳。因此,干旱区存在着有机-无机耦合固碳效应,提高干旱区植被覆盖,可以增加有机碳库储量,同时,经有机过程分馏转移到土壤中的CO2可进一步促进土壤硅酸盐矿物风化,使这部分CO2不再返回大气,而是以碳酸盐形式被长久固存。 展开更多
关键词 土壤 生态 干旱区尾闾盐湖 成土碳酸盐 碳稳定同位素 分馏固碳效应
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Effect of biological activated carbon filter depth and backwashing process on transformation of biofilm community
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作者 Wanqi Qi Weiying Li +3 位作者 Junpeng Zhang Xuan Wu Jie Zhang Wei Zhang 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第1期159-169,共11页
The biological activated carbon (BAC) is a popular advanced water treatment to the provision of safe water supply. A bench-scale device was designed to gain a better insight into microbial diversity and community stru... The biological activated carbon (BAC) is a popular advanced water treatment to the provision of safe water supply. A bench-scale device was designed to gain a better insight into microbial diversity and community structure of BAC biofilm by using high-throughput sequencing method. Both samples of BAC biofilm (the first, third and fifth month) and water (inlet water and outlet water of carbon filter, outlet water of backwashing) were analyzed to evaluate the impact of carbon filter depth, running time and backwash process. The results showed that the microbial diversity of biofilm decreased generally with the increase of carbon filter depth and biofilm reached a steady-state at the top layer of BAC after three months' running. Proteobacteria (71.02%-95.61%) was found to be dominant bacteria both in biofilms and water samples. As one of opportunistic pathogen, the Pseudomonas aeruginosa in the outlet water of device (1.20%) was about eight times higher than that in the inlet water of device (0.16%) at the genus level after five-month operation. To maintain the safety of drinking water, the backwash used in this test could significantly remove Sphingobacteria (from 8.69% to 5.09%, p < 0.05) of carbon biofilm. After backwashing, the operational taxonomic units (OTUs) number and the Shannon index decreased significantly (p <0.05) at the bottom of carbon column and we found the Proteobacteria increased by about 10% in all biofilm samples from different filter depth. This study reveals the transformation of BAC biofilm with the impact of running time and backwashing. 展开更多
关键词 Biological activated CARBON BIOFILM COMMUNITY structure CARBON filter DEPTH HIGH-THROUGHPUT SEQUENCING
The Carbon Isotope Fluctuations across the Lower–Middle Jurassic Boundary and the Paleoclimate Changes 预览
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作者 YI Haisheng XIA Guoqing +5 位作者 LI Gaojie YI Fan ZHANG Shuai CAI Zhanhu JIAO Haijing WU Chihua 《地质学报:英文版》 SCIE CAS CSCD 2019年第1期244-245,共2页
The Qiangtang Basin of Tibetan Plateau most widely outcrops marine Jurassic strata in China,even in eastern Asian,and the Jurassic strata and ammonites’occurrence are in favor of researching evolution of paleoceanogr... The Qiangtang Basin of Tibetan Plateau most widely outcrops marine Jurassic strata in China,even in eastern Asian,and the Jurassic strata and ammonites’occurrence are in favor of researching evolution of paleoceanography in the Tethyan region and global stratigraphic comparison.This work focused on the carbon isotope changes across the J I–J 2 boundary in the eastern Tethys region. 展开更多
关键词 CARBON STRATA Plateau marine CARBON most
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高频感应燃烧红外吸收法测定硅碳复合负极材料中的碳 预览
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作者 陈彩霞 李涛 付鹏飞 《化学分析计量》 CAS 2019年第2期65-67,共3页
采用高频感应燃烧红外吸收法测定硅碳复合负极材料中碳含量。分别考察了称样量,助熔剂种类、用量对测定结果的影响,确定了称样量为100~200mg,以1.5g钨粒、0.8g铁粒和0.3g锡粒为助熔剂。碳的线性相关系数为0.9999,检出限为0.84μg/g,测... 采用高频感应燃烧红外吸收法测定硅碳复合负极材料中碳含量。分别考察了称样量,助熔剂种类、用量对测定结果的影响,确定了称样量为100~200mg,以1.5g钨粒、0.8g铁粒和0.3g锡粒为助熔剂。碳的线性相关系数为0.9999,检出限为0.84μg/g,测定下限为2.8μg/g。测定结果的相对标准偏差为1.83%~2.02%(n=11),样品加标回收率为97.6%~101.1%。该方法快速、准确,适用于硅碳复合负极材料中碳含量的测定。 展开更多
关键词 高频感应燃烧红外吸收法 硅碳复合负极材料
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Diurnal and seasonal variations in carbon fluxes in bamboo forests during the growing season in Zhejiang province,China 预览
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作者 Liang Chen Yuli Liu +5 位作者 Guomo Zhou Fangjie Mao Huaqiang Du Xiaojun Xu Pingheng Li Xuejian Li 《林业研究:英文版》 CAS CSCD 2019年第2期657-668,共12页
Bamboo forest is an important forest type in subtropical China and is characterized by fast growth and high carbon sequestration capacity.However,the dynamics of carbon fluxes during the fast growing period of bamboo ... Bamboo forest is an important forest type in subtropical China and is characterized by fast growth and high carbon sequestration capacity.However,the dynamics of carbon fluxes during the fast growing period of bamboo shoots and their correlation with environment factors are poorly understood.We measured carbon dioxide exchange and climate variables using open-path eddy covariance methods during the 2011 growing season in a Moso bamboo forest(MB,Phyllostchys edulis)and a Lei bamboo forest(LB,Phyllostachys violascens)in Zhejiang province,China.The bamboo forests were carbon sinks during the growing season.The minimum diurnal net ecosystem exchange(NEE)at MB and LB sites were-0.64 and-0.66 mg C m^-2 s^-1,respectively.The minimum monthly NEE,ecosystem respiration(RE),and gross ecosystem exchange(GEE)were-99.3±4.03,76.2±2.46,and-191.5±4.98 g C m-2 month-1,respectively,at MB site,compared with-31.8±3.44,70.4±1.41,and-157.9±4.86 g C m^-2 month^-1,respectively,at LB site.Maximum RE was 92.1±1.32 g C m^-2 month^-1 at MB site and 151.0±2.38 g C m^-2 month^-1 at LB site.Key control factors varied by month during the growing season,but across the whole growing season,NEE and GEE at both sites showed similar trends in sensitivities to photosynthetic active radiation and vapor pressure deficit,and air temperature had the strongest correlation with RE at both sites.Carbon fluxes at LB site were more sensitive to soil water content compared to those at MB site.Both onyear(years when many new shoots are produced)and offyear(years when none or few new shoots are produced)should be studied in bamboo forests to better understand their role in global carbon cycling. 展开更多
关键词 Bamboo forest EDDY COVARIANCE CARBON fluxes CARBON SEQUESTRATION
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Estimating areal carbon fixation of intertidal macroalgal community based on composition dynamics and laboratory measurements 预览
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作者 DU Guoying ZHAO Ezi +1 位作者 LIU Chunrong TANG Xianghai 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第1期93-101,共9页
The community dynamics and potential carbon fixation of intertidal macroalgae were investigated monthly from April 2014 to April 2015 in the northwest coast of Yellow Sea.Seasonal variations in biomass and carbon fixa... The community dynamics and potential carbon fixation of intertidal macroalgae were investigated monthly from April 2014 to April 2015 in the northwest coast of Yellow Sea.Seasonal variations in biomass and carbon fixation were presented and showed close relationship with community structure.The carbon fixation rate ranged from 0.48±0.13 mg C/(g FW·d)to 4.35±0.12 mg C/(g FW·d).Sargassum thunbergii,Chondrus ocellatus and Ulva intestinalis were three most infl uential species which contributed 27%,21.9%and 18.5%variation of carbon fixation rate,respectively.Standing carbon stocks ranged from 7.52 g C/m^2 to 41.31 g C/m^2,and estimated carbon stocks varied from 11.77 g C/m^2 to 96.49 g C/m^2.The larger difference between estimated and standing carbon stocks implied that more fixed carbon was exported from the community in summer and autumn than in winter.This study suggested that intertidal macroalgal community could provide a potential function in carbon fixation of coastal ecosystem. 展开更多
关键词 CARBON FIXATION CARBON STOCK community composition INTERTIDAL MACROALGAE Yellow Sea
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Carbon storage of a subtropical forest ecosystem: a case study of the Jinggang Mountain National Nature Reserve in southeastern China 预览
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作者 Jiping Zhang Linbo Zhang +2 位作者 Haiguang Hao Chunlan Liu Hui Wang 《林业研究:英文版》 CAS CSCD 2019年第3期1011-1021,共11页
The carbon cycle of forest ecosystems plays a key role in regulating CO2 concentrations in the atmosphere. Research on carbon storage estimation of forest ecosystems has become a major research topic. However, carbon ... The carbon cycle of forest ecosystems plays a key role in regulating CO2 concentrations in the atmosphere. Research on carbon storage estimation of forest ecosystems has become a major research topic. However, carbon budgets of subtropical forest ecosystems have received little attention. Reports of soil carbon storage and topographic heterogeneity of carbon storage are limited. This study focused on the Jinggang Mountain National Nature Reserve as an example of a mid-subtropical forest and evaluated soil and vegetation carbon storage by field sampling combined with GIS, RS and GPS technology. We classified the forest into nine forest types using ALOS high-resolution remote sensing images. The evergreen broad-leaved forest has the largest area, occupying 26.5% of the total area, followed by coniferous and broad-leaved mixed forests and warm temperate coniferous forest, occupying 24.2 and 22.9%, respectively. The vegetation and soil carbon storage of the whole forest ecosystem were 1,692,344 and 5,514,707 t, with a carbon density of 7.4 and 24.2 kg/m^2, respectively, which suggests that the ecosystem has great carbon storage capacity. The topographic heterogeneity of the carbon storage was also analysed. The largest vegetation storage and soil storage is at 700–800 and 1000–1100 m, respectively. The vegetation carbon storage is highest in the southeast, south and southwest. 展开更多
关键词 Vegetation CARBON STORAGE Soil CARBON STORAGE Mid-subtropical forest ecosystem Jinggang MOUNTAIN National Nature Reserve
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Discussion on the Ecological Effects of Carbon Source/Sink Conversion in Wetlands 预览
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作者 Houye XI Rende SHI +1 位作者 Yuanyuan LI Xue YU 《农业生物技术:英文版》 CAS 2019年第2期230-231,共2页
This study explored the ecological effects of the transformation of carbon source and carbon sink in wetlands, that were discussed from four aspects: atmosphere, ocean, plants and soil. The results showed that the wet... This study explored the ecological effects of the transformation of carbon source and carbon sink in wetlands, that were discussed from four aspects: atmosphere, ocean, plants and soil. The results showed that the wetland changed from carbon sink to carbon source, which led to the increase of CO2 emissions in the atmosphere and the intensification of greenhouse effect, which made the earth face the threat of global warming. At the same time, the content of CO2 in seawater is increased;the pH value of seawater decreases;the balance of seawater acid-base is destroyed;and the ocean acidification is caused. 展开更多
关键词 WETLANDS CARBON source CARBON SINK ECOLOGICAL effect
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Phosphorous-Modified Carbon Nanotube-Supported Pt Nanoparticles for Propane Dehydrogenation Reaction 预览
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作者 Liu Jie Liu Changcheng +1 位作者 Da Zhijian Zheng Huidong 《中国炼油与石油化工:英文版》 SCIE CAS 2019年第1期7-14,共8页
The sintering of Pt nanoparticles is one of the main reasons for catalyst deactivation during the high-temperature propane dehydrogenation(PDH) reaction. Promoters and supports have been introduced to prolong the cata... The sintering of Pt nanoparticles is one of the main reasons for catalyst deactivation during the high-temperature propane dehydrogenation(PDH) reaction. Promoters and supports have been introduced to prolong the catalyst life.However, it is still necessary to develop novel catalysts with robust stability. Herein, the phosphorus-modified carbon nanotube-supported Pt nanoparticles were employed for the PDH process. Phosphorus modification improves the Pt dispersion, effectively promoting the activity of Pt/P-CNTs. Additionally, the phosphorus-modified CNTs can interact strongly with Pt nanoparticles by improving the electron transfer or hybridization, stabilizing Pt nanoparticles from agglomeration, and significantly enhancing the catalyst stability. 展开更多
关键词 PROPANE DEHYDROGENATION phosphorus-modified carbon NANOTUBES PLATINUM catalyst strong metal-support interactions
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Persistence of Cry1Ac Protein from Transgenic Bt Cotton Cultivation and Residue Returning in Fields and Its Effect on Functional Diversity of Soil Microbial Communities
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作者 ZHANG Meijun FENG Meichen +3 位作者 XIAO Lujie SONG Xiaoyan Guangwei DING YANG Wude 《土壤圈:英文版》 SCIE CAS CSCD 2019年第1期114-122,共9页
The persistence of Cry1 Ac protein in the soil and its effect on soil microbial communities are a core issue in assessing the ecological risk of transgenic Bacillus thuringiensis(Bt) cotton. In this study a field expe... The persistence of Cry1 Ac protein in the soil and its effect on soil microbial communities are a core issue in assessing the ecological risk of transgenic Bacillus thuringiensis(Bt) cotton. In this study a field experiment was conducted on the cultivation of transgenic Bt cotton(Jin 26 and BtJ i 668) with the immediate returning of residues to the fields, in order to quantify the Cry1 Ac protein content in the fields and investigate its effects on the functional diversity of soil microbial communities. Cry1 Ac protein in the residue-soil mixture was gradually degraded in the transgenic Bt cotton fields. After transgenic Bt cotton straw was returned to the fields for 30 d, 63.73%and 58.33% of the initial amounts of Cry1 Ac protein were degraded in the Jin 26 and BtJ i 668 fields, respectively. Before the crops were sown in the following year(180 d after returning the straw), no Cry1 Ac protein was detected in the fields. After returning the cotton straw to the fields for 30 d, the Shannon-Wiener and McIntosh indices of soil microbial communities in the transgenic Bt cotton fields were significantly higher than those in the non-transgenic cotton fields. Meanwhile, the utilization of carbon sources including amino acids, amines, and carbohydrates by the soil microbial communities significantly increased. Both the McIntosh index and the utilization of carbohydrates increased until 180 d. Principal component analysis revealed that amino acids, amides, and carbohydrates were the main carbon sources distinguishing the two principal component factors. These findings indicated that Cry1 Ac protein did not accumulate in the fields after transgenic Bt cotton was planted for one year and the residues were immediately returned to the fields;however, the original functional diversity of soil microbial communities was affected continuously. 展开更多
关键词 BIOLOG GN2 carbon source utilization diversity index principal component analysis STRAW return
高频燃烧-红外吸收法测定金属铪中碳含量研究 预览
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作者 蒙益林 高帅 +1 位作者 颜京 刘铭 《失效分析与预防》 2019年第1期18-22,共5页
称取0.5g金属铪样品置于瓷坩埚中,加入0.3g纯铁和1.5g钨锡粒助熔剂,设定高频燃烧红外碳分析功率为80%,吹扫和延迟时间均为10s,比较水平为2,以钢铁碳标准物质样单点校准设备,绘制校准曲线,并用标准物质验证曲线准确性,建立金属铪中碳含... 称取0.5g金属铪样品置于瓷坩埚中,加入0.3g纯铁和1.5g钨锡粒助熔剂,设定高频燃烧红外碳分析功率为80%,吹扫和延迟时间均为10s,比较水平为2,以钢铁碳标准物质样单点校准设备,绘制校准曲线,并用标准物质验证曲线准确性,建立金属铪中碳含量的测定方法,测量范围为0.001%~0.040%。采用该方法对2个厂家的金属铪中碳含量进行测定,测定结果的相对标准偏差不大于8%,在2个金属铪样品中加入钢铁碳标样进行加标回收试验,回收率在85%~106%之间。 展开更多
关键词 金属铪 高频燃烧感应 红外吸收法
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基于中速-高速摩擦实验研究含碳断层带的电导率特征
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作者 韩明明 杨晓松 +2 位作者 姚路 陈进宇 马胜利 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2019年第3期967-981,共15页
野外地质调查结果显示,断层带常富集碳质.断层带中碳的分布结构是影响断层带电导率特征的一种重要参数.本文在室温、室内湿度和2MPa正应力条件下,对不同石墨含量(3,5,6和7wt%)的石英-石墨混合断层泥模拟样品开展了滑动速率介于500μm... 野外地质调查结果显示,断层带常富集碳质.断层带中碳的分布结构是影响断层带电导率特征的一种重要参数.本文在室温、室内湿度和2MPa正应力条件下,对不同石墨含量(3,5,6和7wt%)的石英-石墨混合断层泥模拟样品开展了滑动速率介于500μm·s^-1~1m·s^-1的摩擦实验及相应的电导率测量,以期研究断层运动对碳分布结构的影响以及断层带电性特征对碳含量及分布的响应情况.结果显示,摩擦滑动能够显著地改变样品的电性特征(电导率大小及其各向异性).在平行滑动面方向(径向),样品电导率随着滑动位移的增加快速增加,在滑动约数十厘米之后,其电导率基本达到稳定状态;在垂直滑动面方向(轴向),样品电导率基本不随摩擦滑动速率和滑动距离而变化.SEM显微结构观测显示,摩擦滑动所引起的电导率各向异性直接反映了石墨分布结构的变化.该研究结果深化了对地震断裂带浅部电性特征的认识,为野外断层带大地电磁测深资料的解释提供了约束,同时对于了解含碳断层的力学性质和弱矿物相在剪切变形中的分布特征及其演化过程等方面也具有重要意义. 展开更多
关键词 断层带电导率 导电结构 摩擦滑动 碳质 石墨
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聚偏二氟乙烯/炭黑复合膜的制备与介电性能 预览
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作者 邓丽媚 焦元启 杨冬 《广州化工》 CAS 2019年第3期68-71,共4页
添加高介电陶瓷粒子来提高复合材料的介电常数常因高含量陶瓷粒子影响复合材料的力学性能。本文将炭黑粒子引入到聚偏二氟乙烯(PVDF)中来降低陶瓷粒子的用量,通过固相混合法将PVDF和炭黑粒子混合后热压制备两相高介电复合材料。利用傅... 添加高介电陶瓷粒子来提高复合材料的介电常数常因高含量陶瓷粒子影响复合材料的力学性能。本文将炭黑粒子引入到聚偏二氟乙烯(PVDF)中来降低陶瓷粒子的用量,通过固相混合法将PVDF和炭黑粒子混合后热压制备两相高介电复合材料。利用傅立叶红外光谱、X射线衍射、差示扫描量热仪、热重分析、动态力学分析仪和宽频介电谱阻抗分析仪等手段对复合材料的结构和性能进行分析发现。炭黑粒子均匀地分散在PVDF基体中,并存在一定的化学键作用。复合材料的力学性能随着炭黑粒子的升高而降低很小,当炭黑含量为3%时,介电常数最高达到19。 展开更多
关键词 纳米复合材料 介电常数 碳黑
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Rdh13 deficiency weakens carbon tetrachloride-induced liver injury by regulating Spotl4 and Cyp2e1 expression levels
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作者 Xiaofang Cui Benting Ma +6 位作者 Yan Wang Yan Chen Chunling Shen Ying Kuang Jian Fei Lungen Lu Zhugang Wang 《医学前沿:英文版》 CAS CSCD 2019年第1期104-111,共8页
Mitochondrion-localized retinol dehydrogenase 13 (Rdh13) is a short-chain dehydrogenase/reductase involved in vitamin A metabolism in both humans and mice. We previously generated Rdh13 knockout mice and showed that R... Mitochondrion-localized retinol dehydrogenase 13 (Rdh13) is a short-chain dehydrogenase/reductase involved in vitamin A metabolism in both humans and mice. We previously generated Rdh13 knockout mice and showed that Rdh13 deficiency causes severe acute retinal light damage. In this study, considering that Rdh13 is highly expressed in mouse liver, we further evaluated the potential effect of Rdh13 on liver injury induced by carbon tetrachloride (CC14). Although Rdh13 deficiency showed no significant effect on liver histology and physiological functions under regular culture, the Rdh13^-/- mice displayed an attenuated response to CCl4-induced liver injury. Their livers also exhibited less histological changes and contained lower levels of liver-related metabolism enzymes compared with the livers of wild-type (WT) mice. Furthermore, the Rdhl3 1 mice had Rdh13 deficiency and thus their liver cells were protected from apoptosis, and the quantity of their proliferative cells became lower than that in WT after CC14 exposure. The ablation of Rdhl3 gene decreased the expression levels of thyroid hormone-inducible nuclear protein 14 (Spot14) and cytochrome P450 (Cyp2el) in the liver, especially after CC14 treatment for 48 h. These data suggested that the alleviated liver damage induced by CC14 in Rdh13^-/- mice was caused by Cyp2el enzymes, which promoted reductive CC14 metabolism by altering the status of thyroxine metabolism. This result further implicated Rdhl3 as a potential drug target in preventing chemically induced liver injury. 展开更多
关键词 RETINOL DEHYDROGENASE 13 carbon TETRACHLORIDE acute liver injury Cyp2el Spot14
Cobalt and nitrogen codoped porous carbon as superior bifunctional electrocatalyst for oxygen reduction and hydrogen evolution reaction in alkaline medium
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作者 Xiaoxia Chen Xiangjun Zhen +6 位作者 Hongyu Gong Le Li Jianwei Xiao Zhi Xu Deyue Yan Guyu Xiao Ruizhi Yang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第3期681-685,共5页
Cobalt and nitrogen codoped carbon materials(Co-N-C) were fabricated by pyrolysis of the mixture of poly(4-vinylpyridine) and cobalt chloride using SiO2 nanoparticles as hard template, which were the first transition ... Cobalt and nitrogen codoped carbon materials(Co-N-C) were fabricated by pyrolysis of the mixture of poly(4-vinylpyridine) and cobalt chloride using SiO2 nanoparticles as hard template, which were the first transition metal/nitrogen-codoped carbon bifunctional electrocatalyst derived from noncarbonizable polymer for ORR and HER. The as-made Co-N-C possessed hierarchical pore structure and high specific surface area, achieving excellent electrocatalytic performances for ORR and HER. Its ORR catalytic performances were comparable to those of Pt/C catalyst and its HER catalytic performances were superior to those of most doped carbon catalysts in KOH electrolyte. Moreover, its bifunctional electrocatalytic performances for ORR and HER were better than those of most bifunctional doped carbon catalysts in alkaline electrolyte. 展开更多
关键词 Carbon COBALT and NITROGEN Doped Oxygen reduction REACTION Hydrogen evolution REACTION
Nanoscale zero-valent iron/magnetite carbon composites for highly efficient immobilization of U(VI)
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作者 Zhimin Lv Shimin Yang +3 位作者 Lei Chen Ahmed Alsaedi Tasawar Hayat Changlun Chen 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第2期377-387,共11页
Nanoscale zerovalent iron/magnetic carbon (NZVI/MC) composites were successfully synthesized by simply calcining yellow pine and iron precursors. NZVI/MC pyrolyzed at 800℃ (NZVI/MC800) had a higher percentage of NZVI... Nanoscale zerovalent iron/magnetic carbon (NZVI/MC) composites were successfully synthesized by simply calcining yellow pine and iron precursors. NZVI/MC pyrolyzed at 800℃ (NZVI/MC800) had a higher percentage of NZVI and displayed better resistance to aggregation and oxidation of NZVI than samples prepared at other temperatures. The NZVI/MC800 material was applied for the elimination of U(VI) from aqueous solutions. The results suggested that the NZVI/MC800 displayed excellent adsorption capacity (203.94mg/g) toward U(VI). The significant adsorption capacity and fast adsorption kinetics were attributed to the presence of well-dispersed NZVI, which could quickly reduce U(VI) into U(IV), trapping the guest U(IV) in the porous biocarbon matrix. The removal of U(VI) on the NZVI/MC samples was strongly affected by solution pH. The NZVI/MC samples also displayed outstanding reusability for U(VI) removal after multiple cycles. These findings indicate that NZVI/MC has great potential for remediation of wastewater containing U(VI). 展开更多
关键词 U(VI) Carbon NZVI ADSORPTION mechanism Reduction
One-pot hydrothermal fabrication ofα-Fe2O3@C nanocomposites for electrochemical energy storage 预览
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作者 Maiyong Zhu Jiarui Kan +4 位作者 Jianmei Pan wenjie Tong Qi Chen Jiacheng Wang Songjun Li 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第1期1-8,共8页
A facile hydrothermal method was developed for the preparation of Fe2O3@C nanocomposites using FeCl3·6H2O as iron source and glucose as carbon source under alkaline condition. The morphology and structure of the ... A facile hydrothermal method was developed for the preparation of Fe2O3@C nanocomposites using FeCl3·6H2O as iron source and glucose as carbon source under alkaline condition. The morphology and structure of the as-prepared product were identified by transmission electron microscopy(TEM), high resolution transmission electron microscopy(HRTEM), field-emission scanning electron microscopy(FESEM),X-ray diffraction(XRD), Raman spectroscopy, Fourier Transform infrared spectroscopy(FTIR), and thermogravimetric analysis(TGA). The as-prepare α-Fe2O3@C nanocomposites were employed for supercapacitor electrode material. The synergistic combination of carbon electrical double-layer capacitance and α-Fe2O3 pseudo-capacitance established such nanocomposites as versatile platform for high performance supercapacitors. The synthesis method developed here is expected to obtain other metal oxide/carbon composite. 展开更多
关键词 Α-FE2O3 Carbon HYDROTHERMAL PSEUDOCAPACITOR
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Multiple active components synergistically driven heteroatom-doped porous carbon as high-performanee counter electrode in dye-sensitized solar cells 预览
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作者 Hongyu Jing Danyang Wu +4 位作者 Suxia Liang Xuedan Song Yonglin An Ce Hao Yantao Shi 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第4期89-94,共6页
A facile template-free in situ self-activation approach for the multiple active components synergistically driven porous carbon was presented via a feasible annealing process.The biomass-derived carbon without additio... A facile template-free in situ self-activation approach for the multiple active components synergistically driven porous carbon was presented via a feasible annealing process.The biomass-derived carbon without additional activation reagents was fabricated using K-rich pomelo peel (PP) as the carbon source,which possesses a high electric conductivity where abundant functional hetero-metal atoms are doped into the carbon framework that playing the role of catalytic graphitization.The K^+ that exists within the biomass can induce self-activation during pyrolysis apart from the activating gases during the pyrolysis process.The resulting electrocatalyst of PP-850 (PP was pyrolyzed at 850℃ in an N2 atmosphere) with abundant heteroatoms possesses a higher power conversion efficiency (PCE) of 7.81% as the counter electrode (CE) of dye-sensitized solar cells (DSCs) compared with the CEs calcinated at other temperatures and a similar PCE with Pt counterpart (8.24%) based on the liquid I3/I^- electrolyte.The better electrocatalytic performance is attributed to rhe synergistic effect between self-activation and the co-doping of nitrogen,sulfur and phosphorus all together in a carbon matrix.Due to the feasibility of large-scale production,rich heteroatom doping,the PP-derived carb on,which simplifies the procedure and decreases the cost,has a pote ntial application for an alter native electrocatalyst for high-performa nee photovoltaic devices. 展开更多
关键词 COUNTER ELECTRODE Self-activation Biomass-derived carbon ELECTROCATALYTIC performance
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Activated carbon fibers with manganese dioxide coating for flexible fiber supercapacitors with high capacitive performance 预览
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作者 Huifang Li Jiachen Liang +4 位作者 Huan Li Xiaoyu Zheng Ying Tao Zheng-Hong Huang Quan-Hong Yang 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第4期95-100,共6页
Fiber supercapacitor (FSC) is a promising power source for wearable/stretchable electronics and high capacitive performs nee of FSCs is highly desirable for practice flexible applications.Here,we report a composite of... Fiber supercapacitor (FSC) is a promising power source for wearable/stretchable electronics and high capacitive performs nee of FSCs is highly desirable for practice flexible applications.Here,we report a composite of manganese dioxide (MnO2) and activated carbon fibers (ACFs) with high MnO2 mass loading and microporous structure (abbreviated as MnO2@ACF),which is used as a fiber electrode to produce a FSC with a high capacitive performance and a good flexibility.The MnO2@ACF composite electrode in FSCs delivers an ultrahigh specific capacitance of 410 mF/cm^2 at 0.1 mA/cm2.corresp on ding to a high energy density of 36 μWh/cm2 and high power density of 726 pW/cm^2.Such high capacitive performs nee and simple fabrication method indicates that the MnO2@ACF composite is a very promising electrode material for flexible fiber supercapacitors. 展开更多
关键词 FIBER SUPERCAPACITORS ACTIVATED carbon fibers MASS loading FLEXIBILITY
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Precise carbon structure control by salt template for high performance sodium-ion storage 预览
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作者 Dong Qiu Tengfei Cao +6 位作者 Jun Zhang Si-Wei Zhang Dequn Zheng Haoliang Wu Wei Lv Feiyu Kang Quan-Hong Yang 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第4期101-106,共6页
Carbon materials are considered to be one of the most promising anode materials for sodium-ion batteries (SIBs),but the well-ordered graphitic structure limits the intercalation of sodium ions.Besides,the sluggish int... Carbon materials are considered to be one of the most promising anode materials for sodium-ion batteries (SIBs),but the well-ordered graphitic structure limits the intercalation of sodium ions.Besides,the sluggish intercalation kinetics of sodium ions impedes the rate performance.Thus,the precise structure control of carbon materials is im porta nt to improve the battery performance.Herein,a 3D porous hard-soft composite carbon (3DHSC) was prepared using the NaCl as the template and phenolic resin and pitch as carbon precursors.The NaCl template restrains the growth of the graphite crystallite during the carb on izatio n process,resulting in small graphitic domains with expanded interlayer spacing which is favorable for the sodium storage.Moreover,the NaCl templates help to create abundant mesopores and macropores for fast sodium ion diffusion.The porous structure and the graphite crystalline structure can be precisely controlled by simply adjusting the mass ratio of NaCl,and thus,the su让able structure can be prepared to reach high capacity and rate performance while keeping a relatively high Coulombic efficiency.Typically,a high reversible capacity (215mAhg^-1 at 0.05Ag^-1),an excellent rate capability (97 mAhg^-1 at 5 Ag^-1),and a high initial Coulombic efficiency (60%) are achieved. 展开更多
关键词 Sodium-ion batteries Salt-template 3D porous hard-soft composite carbon ANODE Electrochemical performance
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