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Characteristics of carbonaceous aerosols analyzed using a multiwavelength thermal/optical carbon analyzer: A case study in Lanzhou City
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作者 Yulan ZHANG Shichang KANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第2期389-402,共14页
Characteristics of atmospheric carbonaceous aerosols in Lanzhou City from December 2014 to November 2015 are analyzed using a multiwavelength thermal/optical carbon analyzer. Results reveal that average concentrations... Characteristics of atmospheric carbonaceous aerosols in Lanzhou City from December 2014 to November 2015 are analyzed using a multiwavelength thermal/optical carbon analyzer. Results reveal that average concentrations of black carbon (BC) and organic carbon in atmospheric aerosols at Lanzhou are 6.7 and 25.4 μg m-3, respectively, showing obvious seasonality (higher in winter and lower in summer). This is consistent with findings in cities of northern China. Primary organic aerosols and secondary organic aerosols respectively account for approximately 60% and 17% of carbonaceous aerosols. No significant seasonality is found for secondary organic carbon, indicating that its potential sources do not vary significantly throughout the study period. The mass absorption cross-section (MAC632nm) of BC is 7.1 m2g-1, slightly higher than that of immediately emitted BC. MAC values of BC at different wavelengths vary drastically;they are higher for ultraviolet and visible light (8.5–10.2 m2g-1) than for near-infrared light (4.9–5.7 m2g-1). The aerosol absorption optical depth generally declines from the near-infrared to the near-ultraviolet region. The values are higher in winter than in summer, thus showing there are different contributions of BC deposition in different seasons. Brown carbon (BrC) has an ?ngstr?m absorption exponent (AAE) value of approximately 2.75, which is similar to the AAE value of BrC generated by diesel combustion (2.3). The contribution of BrC to light absorption is as much as 34% at a wavelength of 635 nm. This study demonstrates that the multiwavelength thermal/optical carbon analyzer can quantify absorption properties of BrC in atmospheric aerosols. This can enhance understanding of carbonaceous aerosols and provide key parameters for simulations of climate models. 展开更多
关键词 CARBONACEOUS AEROSOL Black CARBON Organic CARBON Brown CARBON MULTIWAVELENGTH thermal/optical CARBON ANALYZER
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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The Carbon Effects of the Urban Ecological Recreational System Based on Systems Simulation 预览
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作者 Hua LI Helong TONG Xiaoxiang WANG 《系统科学与信息学报:英文版》 CSCD 2019年第2期134-147,共14页
As a major component of urban ecological systems, the urban ecological space is an important carbon pool in the urban carbon circulation. Meanwhile, its special recreational function adds to the complexity of its carb... As a major component of urban ecological systems, the urban ecological space is an important carbon pool in the urban carbon circulation. Meanwhile, its special recreational function adds to the complexity of its carbon effects. According to the carbon process and effects of the urban ecological recreational system, the Source-Leakage-Sink-Order(SLSO) framework is proposed as the basis of the four subsystems of the system model. Consisting of 63 parameters, the system dynamics model of urban ecological recreational system is constructed by using VENSIM PLE. Then the urban ecological recreational system in Shanghai under different scenarios is simulated, and the carbon sources and sinks of the system as well as the process of carbon effects such as carbon footprints are analyzed and predicted. Research shows that due to the imbalance of the spatial pattern of ecological recreational space, the carbon sink effects of the system are quite limited. The human carbon source is the main contributor of the system’s carbon sources and the carbon footprint deficit is striking. The management ability of ecological recreational space influences the carbon sink potentials of the system. In addition,the maintenance mode of ecological green space plays a non-trivial role in the composition of carbon sources. 展开更多
关键词 URBAN ECOLOGICAL RECREATIONAL SYSTEM URBAN ECOLOGICAL space CARBON EFFECTS CARBON sinks CARBON sources
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Carbon Storage and Distribution of the Mature Pinus massoniana Plantation in Northwest Guangxi 预览
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作者 Zhenge HUANG Minyang XIE +4 位作者 Mingbao WEI Bin HE Shaozhuang MO Gang ZHOU Ji LIANG 《农业生物技术:英文版》 CAS 2019年第3期141-144,共4页
[Objectives]This study was conducted to understand the carbon sequestration function of mature Pinus massoniana plantation in northwest Guangxi.[Methods]The carbon storage and distribution in a 26-year-old P.massonian... [Objectives]This study was conducted to understand the carbon sequestration function of mature Pinus massoniana plantation in northwest Guangxi.[Methods]The carbon storage and distribution in a 26-year-old P.massoniana plantation were investigated through biomass harvesting in Shankou Forestry Farm of Nandan County,Guangxi Province.[Results]The average carbon content of P.massoniana was 489.3 g/kg,and the carbon contents of different organs ranked from large to small as pine needles > trunks > trunk bark > roots > branches.The carbon contents of understory shrub layer,herb layer and litter layer were 453.0,425.6 and 482.5 g/kg,respectively.The soil organic carbon content in forestland varied from 6.20 to 32.15 g/kg,decreasing with the depth of the soil layer.The carbon storage of the mature P.massoniana plantation ecosystem was 232.13 t/hm^2,of which the tree layer,shrub layer,herb layer,litter layer and soil layer were 92.67,1.36,1.12 and 134.49 t/hm^2,respectively,which accounted for 39.92%,0.59%,0.48%,1.07% and 57.94% of the carbon storage of the whole ecosystem,respectively.The annual net productivity of the tree layer of the mature P.massoniana plantation was 10.36 t/(hm^2·a),the annual net carbon sequestration was 5.41 t/(hm^2·a),and the annual net CO2 absorption was 19.83 t/(hm^2·a).[Conclusions]This study provides basic data and scientific basis for rational evaluation of the ecological benefits of P.massoniana plantation in this area. 展开更多
关键词 PINUS massoniana MATURE FOREST CARBON CONTENT CARBON STORAGE
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Terrestrial dissolved organic carbon consumption by heterotrophic bacterioplankton in the Huanghe River estuary during water and sediment regulation 预览
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作者 ZHANG Mingliang YU Guanglei +4 位作者 WANG Fei LI Bin HAN Huizong QI Zhanhui WANG Tengteng 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第3期1062-1070,共9页
Nearly 20%–50% of the annual terrestrial dissolved organic carbon(DOC)from the Huanghe(Yellow)River was transported to the estuary during the 5-14d of water and sediment regulation.The concentration of DOC increased ... Nearly 20%–50% of the annual terrestrial dissolved organic carbon(DOC)from the Huanghe(Yellow)River was transported to the estuary during the 5-14d of water and sediment regulation.The concentration of DOC increased sharply during the period of water and sediment regulation,which may promote the terrestrial DOC consumption by heterotrophic bacterioplankton.Water and sediment regulation provides an ideal condition for the study of terrestrial DOC consumption by heterotrophic bacterioplankton when terrestrial DOC increases sharply in rainy season,which may help to seek the fates of terrestrial DOC in the estuaries and coasts.In this study,the concentration and stable isotope of DOC,the biomass,growth,and respiration of heterotrophic bacterioplankton were determined.By the study,we found both average percent contribution of terrestrial DOC to the DOC pool and Contribution of terrestrial DOC to the carbon composition of heterotrophic bacterioplankton decreased as distance from the river mouth increased off shore,which was deceased from(39.2±4.0)%,(37.5±4.3)%to(30.3±3.9)%,(28.2±3.9)%respectively.255-484μg C/(L·d)terrestrial DOC was consumed by heterotrophic bacterioplankton.And 29%-45%terrestrial DOC consumed by heterotrophic bacterioplankton releasing as CO2 by respiration.Comparing with tropical estuary,terrestrial DOC consumed by heterotrophic bacterioplankton was lower in temperate estuary(this study).Temperature may limit the consumption of terrestrial DOC by heterotrophic bacterioplankton. 展开更多
关键词 TERRESTRIAL dissolved organic CARBON HETEROTROPHIC BACTERIOPLANKTON CARBON stable ISOTOPE BIOGEOCHEMICAL cycles
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A global carbon market?
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作者 Michael G. POLLITT 《工程管理前沿:英文版》 2019年第1期5-18,共14页
This paper explores the prospects for a global carbon market as the centerpiece of any serious attempt to reach the ambitious goal for greenhouse gas (GHG) reductions set by climate scientists. My aim is to clarify th... This paper explores the prospects for a global carbon market as the centerpiece of any serious attempt to reach the ambitious goal for greenhouse gas (GHG) reductions set by climate scientists. My aim is to clarify the extent to which we know what policy might best support global decarbonisation. We begin by discussing what we might mean by a global carbon market and its theoretical properties. We then go on to discuss the EU Emissions Trading System experience and the recent experience with the Australian carbon tax. Next, we assess recent carbon market initiatives in the US and in China. My argument is that while establishing the amount of emissions required and dividing it up acceptably between countries requires an enormous scientific and international negotiations effort, the economic instruments to deliver the agreed targets are readily at hand. 展开更多
关键词 CARBON MARKET CARBON TAX EU ETS
Scanning Mode Application of Neutron-Gamma Analysis for Soil Carbon Mapping
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作者 Aleksandr KAVETSKIY Galina YAKUBOVA +4 位作者 Nikolay SARGSYAN Clyde WIKLE Stephen A. PRIOR Henry Allen TORBERT Bryan A. CHIN 《土壤圈:英文版》 SCIE CAS CSCD 2019年第3期334-343,共10页
Soil carbon mapping is extremely useful in assessing the effect of land management practices on soil carbon storage. Applications of neutron-gamma analysis in scanning mode for mapping of soil carbon are discussed. A ... Soil carbon mapping is extremely useful in assessing the effect of land management practices on soil carbon storage. Applications of neutron-gamma analysis in scanning mode for mapping of soil carbon are discussed. A Global Positioning System(GPS) device and softwares required to simultaneously acquire gamma signals and geographical positions during scanning operations were added to an existing measurement system. The reliability of soil carbon measurements in scanning mode was demonstrated to be in agreement with results acquired from static mode. The error analysis indicated that scanning measurements can be conducted with the same accuracy as static measurements in approximately one fourth the time. To obtain results suitable for mapping analogous to traditional chemical analyses(i.e.,± 0.5 in weight percent or ± 0.5 w%), scanning time over a given site should be ca. 15 min using the current measurement system configuration. Based on this measurement time, a reasonable towing speed of 3–5 km h^-1, the necessity for complete site coverage during scanning, the number of sites(within the surveyed field), and the required total measurement time can be estimated. Soil carbon measurements for 28 field sites(total area ca. 2.5 ha) were conducted in ca. 8 h. Based on acquired data,a soil carbon distribution map was constructed utilizing various softwares. The surveyed field area included an asphalt road that had carbon readings higher than the surrounding land. The clarity with which these carbon-rich zones were delineated on the constructed map represents evidence supporting the veracity of this method. Neutron-gamma analysis technology can greatly facilitate timely construction of soil carbon maps. 展开更多
关键词 ArcGIS Google Earth Pro IGOR SCANNING technology SOIL CARBON distribution map SOIL CARBON storage
A ketone-functionalized aromatic saddle as a potential building block for negatively curved carbon nanobelts
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作者 Kwan Yin Cheung Qian Miao 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第8期1506-1508,共3页
A novel ketone-functionalized aromatic saddle consisting of 72 sp^2 carbon atoms is successfully synthesized and unambiguously identified with X-ray crystallography.It can,in principle,be used as a building block for ... A novel ketone-functionalized aromatic saddle consisting of 72 sp^2 carbon atoms is successfully synthesized and unambiguously identified with X-ray crystallography.It can,in principle,be used as a building block for synthesis of negatively curved carbon nanobelts and for a bottom-up approach to negatively curved carbon allotropes. 展开更多
关键词 Polycyclic arenes Synthesis Negatively curved carbon allotropes Carbon nanobelts Scholl reaction
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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Impact of carbon-based nutrient enhancement on biofiltration performance for drinking water treatment
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作者 Yu Zhao Liz Taylor-Edmonds Robert C. Andrews 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第8期124-131,共8页
Incorporation of a carbon-based nutrient enhancementstrategy for drinking water biofiltration is an attractive option, especially for source waters which contain recalcitrant organics. This study compared biofilters t... Incorporation of a carbon-based nutrient enhancementstrategy for drinking water biofiltration is an attractive option, especially for source waters which contain recalcitrant organics. This study compared biofilters that were operated in parallel and individually enhanced with amino acids(including alanine, phenylalanine, and tryptophan), inulin, and sucrose to increase biomass concentration and promote biodegradation of dissolved organic carbon(DOC) in the source water, including disinfection by-product(DBP) precursors. Biomass activity was characterized by measuring adenosine tri-phosphate(ATP), dissolved oxygen(DO) consumption, and through the use of laccase and esterase enzyme assays. Performance was evaluated in terms of headloss,turbidity, p H, DOC, UV254, and DBP formation potential(DBP FP). The introduction of carbonbased nutrients significantly increased biomass activity, where ATP values peaked at 976 ng/g of filter media, 853 ng/g, and 513 ng/g for amino acids, inulin, and sucrose-spiked biofilters,respectively, while a non-spiked control only reached 104 ng/g. DO utilization by the enhanced biofilters was significantly higher than the control, with a strong correlation between ATP and DO uptake observed for all filters(R~2> 0.74). Laccase and esterase enzyme activities of enhanced biofilters were also elevated(p > 0.05), suggesting greater biodegradation potential. Operational parameters such as headloss development and turbidity control were not impaired by carbon supplementation strategies or an increase in biomass concentration and activity. However, the enhancement strategy did not provide improvement in terms of source water carbon removal(DOC and UV254) or DBP FP when treated filters were compared to a control. 展开更多
关键词 Biological FILTRATION CARBON ENHANCEMENT Biomass DISINFECTION by-products Dissolved organic CARBON
Aerosol light absorption in a coastal city in Southeast China:Temporal variations and implications for brown carbon
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作者 Yuqing Qiu Xin Wu +5 位作者 Yanru Zhang Lingling Xu Youwei Hong Jinsheng Chen Xiaoqiu Chen Junjun Deng 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第6期257-266,共10页
Light-absorbing carbonaceous aerosols including black carbon(BC) and brown carbon(BrC)play significant roles in atmospheric radiative properties. One-year measurements of aerosol light absorption at multi-wavelength w... Light-absorbing carbonaceous aerosols including black carbon(BC) and brown carbon(BrC)play significant roles in atmospheric radiative properties. One-year measurements of aerosol light absorption at multi-wavelength were continuously conducted in Xiamen,southeast of China in 2014 to determine the light absorption properties including absorption coefficients(σabs) and absorption ?ngstr?m exponent(AAE) in the coastal city.Light absorptions of BC and BrC with their contributions to total light absorption were further quantified. Mean σabsat 370 nm and 880 nm were 56.6 ± 34.3 and 16.5 ± 11.2 Mm-1,respectively. σabspresented a double-peaks diurnal pattern with the maximum in the morning and the minimum in the afternoon. σabswas low in warm seasons and high in cold seasons. AAE ranged from 0.26 to 2.58 with the annual mean of 1.46, implying that both fossil fuel combustion and biomass burning influenced aerosol optical properties. σabsof BrC at 370 nm was 24.0 ± 5.7 Mm-1, contributing 42% to the total absorption. The highest AAE(1.52 ± 0.02) and largest BrC contributions(47% ± 4%) in winter suggested the significant influence of biomass burning on aerosol light absorption. Long-distance air masses passing through North China Plain and the Yangtze River Delta led to high AAE and BrC contributions. High AAE value of 1.46 in July indicated that long-range transport of the air pollutants from intense biomass burning in Southeast Asia would affect aerosol light absorption in Southeast China. The study will improve the understanding of light absorption properties of aerosols and the optical impacts of BrC in China. 展开更多
关键词 LIGHT ABSORPTION BROWN CARBON Black CARBON ABSORPTION ANGSTROM exponent Biomass burning Western Taiwan STRAIT
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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Thermal conductivity of natural rubber nanocomposites with hybrid fillers
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作者 Junping Song Xiteng Li +3 位作者 Kaiyan Tian Lianxiang Ma Wei Li Shichune Yao 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第4期928-934,共7页
Natural rubber nanocomposites filled with hybrid fillers of multi-walled carbon nanotubes(CNTs) and carbon black(CB) were prepared. CNTs were ultrasonically modified in mixture of hydrogen peroxide(H2O2) and distilled... Natural rubber nanocomposites filled with hybrid fillers of multi-walled carbon nanotubes(CNTs) and carbon black(CB) were prepared. CNTs were ultrasonically modified in mixture of hydrogen peroxide(H2O2) and distilled water(H2O). The functional groups on the surface of CNTs, changes in nanotube structure and morphology were characterized by Fourier transform infrared spectroscopy(FT-IR), Raman Spectroscopy, and transmission electron microscopy(TEM). It shows that hydroxyl(OH·) is successfully introduced. The surface defects of modified CNTs were obviously higher than those of original CNTs, and the degree of agglomeration was greatly reduced. Thermal conductivity of the composites was tested by protection heat flow meter method. Compared with unmodified CNTs/CB filling system, the thermal conductivity of hybrid composites is improved by an average of 5.8% with 1.5 phr(phr is parts per hundred rubber) of hydroxyl CNTs and 40 phr of CB filled. A three-dimensional heat conduction network composed of hydroxyl CNTs and CB, as observed by TEM, contributes to the good properties. Thermal conductivity of the hybrid composites increases as temperature rises. The mechanical properties of hybrid composites are also good with hydroxyl CNTs filled nanocomposites;the tensile strength, 100% and 300% tensile stress are improved by 10.1%, 22.4% and 26.2% respectively. 展开更多
关键词 Modified CARBON NANOTUBE CARBON black HYBRID FILLER Natural rubber Thermal CONDUCTIVITY
Three-dimensional matrix for lithium metal anode for next-generation rechargeable batteries: Structure design and interface engineering 预览
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作者 Long Kong Qiang Zhang 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第6期167-168,共2页
The next-generation batteries with very high energy/power densities, affordable cost, safe operation are of paramount importance to electric vehicles and grid-scale storage. Lithium (Li) metal anode paired with conver... The next-generation batteries with very high energy/power densities, affordable cost, safe operation are of paramount importance to electric vehicles and grid-scale storage. Lithium (Li) metal anode paired with conversion reaction cathodes (sulfur and oxygen) is regarded as a Holy Grail research because such battery system can employ earth-abundant elements and afford 3?5 times higher energy density than current lithium ion batteries (3500 Wh kg^-1 for lithium-oxygen batteries and 2600 Wh kg^-1 for lithium-sulfur batteries)[1]. 展开更多
关键词 LITHIUM metal anode CARBON NANOFIBERS Nitrogen doped CARBON NANOMATERIALS DENDRITE formation Electrochemical energy storage
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Carbonaceous aerosol in ambient air: Parallel measurements between water cyclone and carbon analyzer
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作者 Min-Suk Bae James J. Schwab +2 位作者 Da-Jeong Park Zang-Ho Shon Ki-Hyun Kim 《颗粒学报:英文版》 SCIE EI CAS CSCD 2019年第3期153-158,共6页
A water cyclone,developed to collect and preserve biological aerosols in a small liquid flow,was interfaced with a total organic carbon analyzer to measure the aerosol organic and inorganic carbon fractions.The total ... A water cyclone,developed to collect and preserve biological aerosols in a small liquid flow,was interfaced with a total organic carbon analyzer to measure the aerosol organic and inorganic carbon fractions.The total carbon was compared against parallel measurements of elemental carbon (EC) and organic carbon (OC) using a Sunset Real Time ECOC Analyzer between 12-29 January 2009.A National Institute for Occupational Safety and Health (NIOSH) like protocol for the measurements included four temperature steps ending at 840 ℃ for OC under a helium atmosphere followed by two temperature steps ramped to 850 ℃ for EC in a helium-oxygen atmosphere,Carbon data comparison between the water cyclone-TOC and the TOC measured by the analyzer indicated good agreement (r2 =0.82,linear regression slope =0.98,p < 0.001).Analyses of the relationship between total water organic carbon and OC,investigated using data sets from case studies spanning two different events,suggested it was possible to distinguish between the primary and secondary sources. 展开更多
关键词 WATER soluble ORGANIC CARBON Total ORGANIC CARBON CARBONACEOUS material
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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四川盆地西缘峨眉含笑-喜树混交林凋落物量及碳氮磷动态特征
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作者 蒲悦 毛绘友 +3 位作者 刘群 庄丽燕 杨开军 徐振锋 《应用与环境生物学报》 CAS CSCD 北大核心 2019年第2期262-267,共6页
为认识四川盆地西缘亚热带典型阔叶混交林的凋落物产量模式与养分动态特征,通过直接收集法收集凋落物,对四川盆地西缘乡土珍贵树种峨眉含笑-喜树混交林凋落物产量、碳氮磷含量及归还量月动态进行了为期1年(2016)的观测和分析.结果显示:... 为认识四川盆地西缘亚热带典型阔叶混交林的凋落物产量模式与养分动态特征,通过直接收集法收集凋落物,对四川盆地西缘乡土珍贵树种峨眉含笑-喜树混交林凋落物产量、碳氮磷含量及归还量月动态进行了为期1年(2016)的观测和分析.结果显示:混交林中叶的年凋落物总量为2 853.36 kg/hm^2,其中含笑1 644.82 kg/hm^2,喜树1 208.54 kg/hm^2.两种林木凋落叶产量季节动态明显,含笑凋落叶量最大值在出现4月(476.03 kg/hm^2),最小值出现在9月(43.73 kg/hm^2);而喜树最大值和最小值分别出现在11月(534.41 kg/hm^2)和6月(21.58 kg/hm^2).含笑和喜树凋落叶中碳氮磷含量在夏季相对较高.含笑凋落叶碳氮磷归还量高峰均在4月和11月;喜树凋落叶碳氮磷归还高峰均在11月.混交林凋落叶的碳氮磷年总归还量分别为1 186.11、38.78、1.76 kg/hm^2.总之,该区域混交林凋落物产量月动态模式主要受控于林木生物学特性,且凋落物碳氮磷含量和归还量存在明显季节性变化;结果可为区域生态系统相似混交林的保护和恢复提供理论依据. 展开更多
关键词 峨眉含笑 喜树 叶凋落物量 碳氮磷含量 碳氮磷归还量
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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