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“碳中和”背景下国有煤炭企业实现产业转型的措施分析 被引量:1
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作者 张航 《现代工业经济和信息化》 2023年第6期235-236,共2页
对“碳中和”合背景下国有煤炭企业的产业转型升级进行探讨分析。分析认为,“碳达峰”“碳中和”将对我国未来的能源格局产生重大影响。节能减排将进一步压减煤炭消耗量,新能源逐步替代火电,绿色、低碳、环保制约煤企发展。煤炭作为不... 对“碳中和”合背景下国有煤炭企业的产业转型升级进行探讨分析。分析认为,“碳达峰”“碳中和”将对我国未来的能源格局产生重大影响。节能减排将进一步压减煤炭消耗量,新能源逐步替代火电,绿色、低碳、环保制约煤企发展。煤炭作为不可再生资源,随着煤炭高强度开采,资源储量减少所产生的矛盾不断激化,使循环经济模式孕育而出。 展开更多
关键词 国有煤炭企业 碳中合 循环经济
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Glycemic index of cereals and tubers produced in China 被引量:4
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作者 Yue-Xin Yang Hong-Wei Wang +4 位作者 Hong-Mei Cui Yan Wang Lian-Da Yu Shi-Xue Xiang Shui-Ying Zhou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第21期3430-3433,共4页
AIM: To determine the GI of some cereals and tubers produced in China in an effort to establish the database of glycemic index (GI) of Chinese food.METHODS: Food containing 50 g carbohydrate was consumed by 8-12 h... AIM: To determine the GI of some cereals and tubers produced in China in an effort to establish the database of glycemic index (GI) of Chinese food.METHODS: Food containing 50 g carbohydrate was consumed by 8-12 healthy adults after they have been fasted for 10 h and blood glucose was monitored for 2 h. Glucose was used as reference food. GI of food was calculated according to a standard method.RESULTS: GI of 9 types of sugar and 60 kinds of food were determined.CONCLUSION: Food GI is mainly determined by nature of carbohydrate and procession. Most of cereals and tubers produced in China have similar GI with their counterparts produced in other countries. 展开更多
关键词 Glycemic Index CEREALS TUBERS CARBOHYDRATE
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Synthesis of mesoporous carbon as electrode material for supercapacitor by modified template method 被引量:3
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作者 赵家昌 赖春艳 +1 位作者 戴扬 解晶莹 《Journal of Central South University of Technology》 EI 2005年第6期647-652,共6页
The pore structures and electrochemical performances of mesoporous carbons prepared by silica sol template method as electrode material for supercapacitor were investigated. The mean pore size and mass specific capaci... The pore structures and electrochemical performances of mesoporous carbons prepared by silica sol template method as electrode material for supercapacitor were investigated. The mean pore size and mass specific capacitance of the mesoporous carbons increase with the increase of mass ratio of silica sol to carbon source (glucose). A modified template method, combining silica sol template method and ZnCl2 chemical activation method, was proposed to improve the mass specific capacitance of the mesoporous carbon with an improved BET surface area. The correlation of rate capability and pore structure was studied by constant current discharge and electrochemical impedance spectroscopy. A commercially available microporous carbon was used for comparison. The result shows that mesoporous carbon with a larger pore size displays a higher rate capability. Mesoporous carbon synthesized by modified template method has both high mass specific capacitance and good rate capability. 展开更多
关键词 SUPERCAPACITOR mesoporous carbon modified template method electrochemical performance SYNTHESIS
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Comparative study on chalcopyrite bioleaching with assistance of different carbon materials by mixed moderate thermophiles 被引量:6
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作者 Ping ZHU Xue-duan LIU +5 位作者 Ai-jia CHEN Hong-wei LIU Hua-qun YIN Guan-zhou QIU Xiao-dong HAO Yi-li LIANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第6期1294-1303,共10页
The catalysis of four carbon materials including artificial graphite(AG), carbon black(CB), activated carbon(AC) and carbon nanotube(CN) on chalcopyrite bioleaching by mixed moderate thermophiles was comparatively inv... The catalysis of four carbon materials including artificial graphite(AG), carbon black(CB), activated carbon(AC) and carbon nanotube(CN) on chalcopyrite bioleaching by mixed moderate thermophiles was comparatively investigated. In AC and AG added bioleaching groups, low solution pH and suitable redox potential values, high total iron and ferric iron concentrations, and large number of adsorbed bacteria were obtained, resulting in high copper extractions. CB and CN inhibited the growth of bioleaching bacteria and led to the low bioleaching efficiency.X-ray diffraction analysis showed that jarosite and sulfur film were the main components of passivation layer with the addition of AG and AC,but did not hinder the dissolution of chalcopyrite. Microbial community structures of free and attached cells in AC and AG added groups changed dramatically compared with mixed moderate thermophiles. The sulfur-oxidizing bacteria of A. caldus S1 strain dominated the microbial community(93%-98%) at the end of bioleaching.The iron-oxidizing bacteria of L.ferriphilum YSK only accounted for low percentage(1%-2%). 展开更多
关键词 CHALCOPYRITE leaching carbon material mixed moderate thermophiles microbial community structure
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Estimation of Digestible Energy Values of Plant Protein Supplement in Pig 被引量:1
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作者 李明元 王康宁 《Agricultural Science & Technology》 CAS 2009年第2期97-101,107,共6页
[Objective] The aim of the study was to establish the effective and accurate formulas for estimating the digestible energy (DE) values of plant protein supplement in pig. [Method] By difference method with different... [Objective] The aim of the study was to establish the effective and accurate formulas for estimating the digestible energy (DE) values of plant protein supplement in pig. [Method] By difference method with different amount of alternative feeds (20% -50%), two4 x4 Latin- square-designed trials were taken on eight castrated male pigs [ Yorkshire x Landrace x Neijiang pig, initial body-weight: (46 ±2) kg ] to deter- mine the apparent digestible energy (ADE) of the eight kinds of plant protein supplement commonly used in China, that is, corn gluten meal (sol.), soybean meal ( sol. ), fababean, pea, rapeseed meal ( sol. ), sesame meal ( sol. ), rapeseed meal ( exp. ) and cotton seed meal (sol.). [Resultl (1) Fiber was the most important factor to estimate the ADE of plant protein supplement in pigs, and ADF was the best one. (2) The most effective equations were as below: ( 1 ) OE (kJ/kg DM) = 14 741.86 - 185.01ADF+54.01SCHO+22.45CP ( R =0.988,RSD= 67.9,P〈0.01 ) ; (2) DE (kJ/kg DM) =22 223.26 -209.58ADF+26.79SCHO-1.09GE ( Ff =0.989,RSD=66.9, P〈0.01 ) . [Conclusion] The accurate, practical and specific regression equations were established for DE prediction of plant protein supplement in pig. 展开更多
关键词 Plant protein supplement PIG Digestible energy ESTIMATION
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Effect of carbon on microstructure,mechanical properties and wear resistance of non-equiatomic Fe_(70)Co_(7.5)Cr_(7.5)Ni_(7.5)V_(7.5) medium-entropy alloys fabricated by powder metallurgy 被引量:2
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作者 YANG Bao-zhen XIONG Xiang +1 位作者 LIU Ru-tie CHEN Jie 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第6期1799-1810,共12页
In this study,non-equiatomic Fe_(70)Co_(7.5)Cr_(7.5)Ni_(7.5)V_(7.5) medium-entropy alloys(MEAs)with different carbon contents were prepared via mechanical ball-milling,cold pressing and vacuum sintering.The microstruc... In this study,non-equiatomic Fe_(70)Co_(7.5)Cr_(7.5)Ni_(7.5)V_(7.5) medium-entropy alloys(MEAs)with different carbon contents were prepared via mechanical ball-milling,cold pressing and vacuum sintering.The microstructural evolution,mechanical properties and wear resistance of the MEAs were investigated.Fe_(70)Co_(7.5)Cr_(7.5)Ni_(7.5)V_(7.5) exhibited a bodycentered cubic(bcc)structure withσphase precipitation.After adding 4 at%and 8 at%carbon,the phase composition of the alloys was transformed to bcc+MC+σand bcc+MC+M_(23)C_(6),respectively.The mechanical properties and wear resistance were observed to be significantly enhanced by the formation of carbides.Increasing the carbon content,the corresponding bending strength and hardness increased from 1520 to 3245 MPa and HRC 57.2 to HRC 61.4,respectively.Further,the dominant wear mechanism changed from the adhesion wear to the abrasion wear.Owing to the evenly distributed carbides and precipitated nanocarbides,Fe_(64.4)Co_(6.9)Cr_(6.9)Ni_(6.9)V_(6.9)C_(8) revealed an extremely low specific wear rate of 1.3×10^(−6) mm_(2)/(N·m)under a load of 10 N. 展开更多
关键词 medium-entropy alloys powder metallurgy CARBIDE wear resistance
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Forecast of Consumption and Emission of HFC-134a Used in the Mobile Air-conditioner Sector in China 被引量:1
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作者 Jianxin Hu Dan Wan +2 位作者 Chunmei Li Jianbo Zhang Xu Yi 《Advances in Climate Change Research》 SCIE 2010年第1期20-26,共7页
HFC-134a is the most important alternative to CFC-12 used in the mobile air-conditioner sector in China. The con- sumption of HFC-134a has been increasing rapidly in recent years. It becomes the most consumed HFC in t... HFC-134a is the most important alternative to CFC-12 used in the mobile air-conditioner sector in China. The con- sumption of HFC-134a has been increasing rapidly in recent years. It becomes the most consumed HFC in the sector. Selecting 2005 as the base line year, future consumption and emission amounts of HFC-134a are estimated through an analysis of a combined scenario: 1) replacement by non-HFC-134a blends, 2) good practice in servicing, 3) technology promotion, and 4) government policies on control of HFC-134a emissions. The analysis shows that HFC-134a consumption and emissions will continue to increase in the next 10 years. The projected HFC-134a consumption will approach 20,150 t and 34,875 t in 2010 and 2015 respectively, while the estimated emission amounts will reach 16,065 t and 30,186 t (i.e., 21 Mt CO2-eq and 39 Mt CO2-eq emissions) correspondingly. Compared with the business-as-usual scenario, the expected emission reductions in 2010 and 2015 will range between 6.7 Mt CO2-eq and 13.0 Mt CO2-eq. 展开更多
关键词 mobile air-conditioner HFC-134A emission reduction
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Response Surface Optimization for Process Parameters of LiFePO_4/C Preparation by Carbothermal Reduction Technology 被引量:2
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作者 杨克迪 谭芳香 +2 位作者 王凡 龙云飞 文衍宣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第4期793-802,共10页
A statistically based optimization strategy is used to optimize the carbothermal reduction technology for the synthesis of LiFePO4/C using LiOH,FePO4 and sucrose as raw materials.The experimental data for fitting the ... A statistically based optimization strategy is used to optimize the carbothermal reduction technology for the synthesis of LiFePO4/C using LiOH,FePO4 and sucrose as raw materials.The experimental data for fitting the response are collected by the central composite rotatable design(CCD).A second order model for the discharge ca-pacity of LiFePO4/C is expressed as a function of sintering temperature,sintering time and carbon content.The ef-fects of individual variables and their interactions are studied by a statistical analysis(ANOVA).The results show that the linear effects and the quadratic effects of sintering temperature,carbon content and the interactions among these variables are statistically significant,while those effects of sintering time are insignificant.Response surface plots for spatial representation of the model illustrate that the discharge capacity depends on sintering temperature and carbon content more than sintering time.The model obtained gives the optimized reaction parameters of sinter-ing temperature at 652.0 ℃,carbon content of 34.33 g?mol-1 and 8.48 h sintering time,corresponding to a dis-charge capacity of 150.8 mA·h·g-1.The confirmatory test with these optimum parameters gives the discharge ca-pacity of 147.2 and 105.1 mA·h·g-1 at 0.5 and 5 C,respectively. 展开更多
关键词 lithium ion battery cathode material lithium iron phosphate carbothermal reduction technology re-sponse surface methodology
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Evaluation of effective carrier system and function on hydrocarbon accumulation in Gaoyou Sag,Subei Basin,China
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作者 李浩 高先志 +2 位作者 孟晓燕 赵赟龙 张明 《Journal of Central South University》 SCIE EI CAS 2013年第6期1679-1692,共14页
Effective carrier system comprises carrier beds which transport hydrocarbons. The spatial and temporal effectiveness of carrier system is identified according to the relevance of hydrocarbon show, hydrocarbon inclusio... Effective carrier system comprises carrier beds which transport hydrocarbons. The spatial and temporal effectiveness of carrier system is identified according to the relevance of hydrocarbon show, hydrocarbon inclusion and sealing ability of fault to hydrocarbons distribution, together with matching relation of activity history of fault and hydrocarbon generation history of source rock. On the basis of the above considerations, transporting ability of effective carrier system can be evaluated using parameters such as fluid potential, porosity and permeability, spatial coefficient of effective pathway as well as activity rate of fault. Additionally, a new concept of"transporting threshold porosity" was proposed. Five styles of effective carrier systems were established in Gaoyou Sag, displaying either layered or zonal distribution characteristics, and transporting time ranges from the sedimentary time of Ezdz to early stage of sanduo uplift. Effective carrier systems can be described to be lowly-efficient and highly-efficient. Major faults (convex or steep fault plane) with activity rate greater than 20 m/Ma and structure ridges of sand layers with spatial coefficient of effective pathway greater than 25% are defined to be highly-efficient carrier beds. Hydrocarbons are concentrated around high-efficient carrier beds and E1 f traps of northern shanian area are predicted to have great potential. 展开更多
关键词 effective carrier system transporting threshold porosity of carrier beds fluid potential hydrocarbon migration GaoyouSag
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The Status Quo and Development Trend of Low-carbon Vehicle Technologies in China
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作者 Xunmin Ou Xiliang Zhang 《Advances in Climate Change Research》 SCIE 2010年第1期34-39,共6页
Three types of low-carbon vehicle technologies in China are reviewed. Potential effects are listed for those integrated energy-saving technologies for conventional vehicles. Low carbon transitions, including alternati... Three types of low-carbon vehicle technologies in China are reviewed. Potential effects are listed for those integrated energy-saving technologies for conventional vehicles. Low carbon transitions, including alternative vehicle power train systems and fuels, are discussed on their development status and trends, including life cycle primary fossil energy use and greenhouse gas emissions of each pathway. To further support the low-carbon vehicle technologies development, integrated policies should seek to: (1) employ those integrated energy-saving technologies, (2) apply hybrid electric technology, (3) commercialize electric vehicles through battery technology innovation, (4) support fuel cell vehicles and hydrogen technology R&D for future potential applications, (5) boost the R&D of second generation biofuel technology, and (6) conduct further research on applying low-carbon technologies including CO2 capture and storage technology to coal-based transportation solutions. 展开更多
关键词 low carbon vehicle technology greenhouse gas
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Comprehensive Appraisal of Provincial Low Carbon Development:A Case Study of China
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作者 Liu Yong 《Chinese Journal of Population,Resources and Environment》 2012年第1期27-31,共5页
In this research,the Factor Analysis model of measuring provincial low carbon development in China has been constructed.Based on data from 30 provinces,an empirical study was developed to measure comprehensive low car... In this research,the Factor Analysis model of measuring provincial low carbon development in China has been constructed.Based on data from 30 provinces,an empirical study was developed to measure comprehensive low carbon development using the Factor Analysis model(Principal Components method and Normalized Varimax Rotation).The results reveal that the provincial marks of low carbon development are generally low and only nine provinces have high marks(more than 0.80).The results also show significant regional disparity.The provincial marks of the eastern region are higher than both the middle and western provinces of China's Mainland.All of the provinces with high marks(more than 0.90) are located in the eastern region,and those with the lowest marks(0.60) are located in the middle region.Furthermore,regional disparity in low carbon development follows the same pattern as economic development in China.Finally,some suggestions for decision-makers are presented. 展开更多
关键词 low carbon development INDICATORS Factor Analysismodel China
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Controversy of International Carbon-motivated Border Tax Adjustment and Its Impact on China's Manufacturing Industries
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作者 Shen Keting 《Chinese Journal of Population,Resources and Environment》 2011年第4期59-70,共12页
Carbon-motivated border tax adjustment (BTA) aims to compensate for the loss of competitiveness of carbon intensive products due to carbon dioxide abatement actions. Based on the analysis of the international backgr... Carbon-motivated border tax adjustment (BTA) aims to compensate for the loss of competitiveness of carbon intensive products due to carbon dioxide abatement actions. Based on the analysis of the international background of carbon-motivated BTAs, this paper discusses the fundamental motivation leading to US policy transformation, the potential impacts of the policy on China's manufacturing industries, and the compatibility of the policy to WTO rules. Carbon-motivated BTAs violate the fundamental principle of the UNFCCC, and potentially conflict with the core WTO principle of non-discrimination reflected in the GATT Articles 1 and III. However, Article XX of the GATT may be applicable. Thus, the author suggests several measures to alleviate the impacts of carbon-motivated BTAs, and puts forward countermeasures based on carbon consumption per capita. 展开更多
关键词 climate change carbon-motivated BTAs manufacturing industry WTO rules
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Convergence Study of Chinese Carbon Intensity
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作者 Bo WANG 《International Journal of Technology Management》 2014年第11期72-75,共4页
This paper establishes the theoretical hypothesis of carbon intensity convergence, and through statistics to analyze and describe the whole country and the eastern and western regions with the use of mixed regression ... This paper establishes the theoretical hypothesis of carbon intensity convergence, and through statistics to analyze and describe the whole country and the eastern and western regions with the use of mixed regression model and fixed effects regression method, and test σ -convergence, absolute convergence and conditional convergence in order to have an empirical study on carbon convergence hypothesis. 展开更多
关键词 carbon emissions INTENSITY CONVERGENCE Economic Growth
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环境规制的产业空间选择效应与区域战略调整
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作者 范玉波 《东岳论丛》 CSSCI 北大核心 2021年第10期162-170,共9页
较多考虑发展阶段和环境承载力的差别化环境政策将造成环境敏感型产业的地区间替代。中国地域辽阔,区域自然资源禀赋、发展阶段差别很大,东部许多地区已经步入相对发达阶段,而一些中西部地区却仍然处于发展阶段,属于欠发达地区。追求经... 较多考虑发展阶段和环境承载力的差别化环境政策将造成环境敏感型产业的地区间替代。中国地域辽阔,区域自然资源禀赋、发展阶段差别很大,东部许多地区已经步入相对发达阶段,而一些中西部地区却仍然处于发展阶段,属于欠发达地区。追求经济平衡发展推行差异化的环境政策无疑突出了后发地区的环境承载力的比较优势,使得环境污染密集型产业向这些地区迁徙,导致污染产业空间重新布局。如果区域发展战略过多考虑区域的平衡发展,以缩小中西部同东部地区的发展差距,而不是严格按照主体功能区进行分类环境保护和人口要素的自由向东部沿海地区流动,污染源就会向中西部地区蔓延。由于中国河流由西向东流的自然特点,产业向中西部布局的实质是向河流上游的转移。西部地区环境的脆弱性、上游性特征非常明显,一旦环境遭到破坏,不仅对当地居民生产、生活带来极大风险,也对整个下游地区的经济社会发展安全带来较大影响。在生态环境保护日益受到重视的大背景下,出台区域战略时,需要注重东西一体联动的区域发展战略,优化整个流域产业和人口布局,注重区域经济发展整体性考虑,以环境功能区政策体现区域发展差别化和产业分工。 展开更多
关键词 环境规制 污染产业布局调整 西部环境污染 污染产业迁移 碳中合
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Geochemistry and possible origin of the hydrocarbons from Wells Zhongshen1 and Zhongshen1C, Tazhong Uplift 被引量:15
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作者 SONG DaoFu WANG TieGuan LI MeiJun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第4期840-850,共11页
In 2013, a great breakthrough of deep petroleum exploration was achieved in the Cambrian pre-salt intervals of Wells Zhongshen1(ZS1) and Zhongshen1C(ZS1C), Tazhong Uplift. However, the hydrocarbon discovery in the Cam... In 2013, a great breakthrough of deep petroleum exploration was achieved in the Cambrian pre-salt intervals of Wells Zhongshen1(ZS1) and Zhongshen1C(ZS1C), Tazhong Uplift. However, the hydrocarbon discovery in the Cambrian pre-salt intervals has triggered extensive controversy regarding the source of marine oils in the Tarim Basin. The geochemistry and origin of the Cambrian pre-salt hydrocarbons in Wells ZS1 and ZS1 C were investigated using GC, GC-MS and stable carbon isotope technique. These hydrocarbons can be easily distinguished into two genetic families based on their geochemical and carbon isotopic compositions. The oil and natural gases from the Awatage Formation of Well ZS1 are derived from Middle-Upper Ordovician source rocks. In contrast, the condensate and gases from the Xiaoerbulake Formation of Wells ZS1 and ZS1 C probably originate from Cambrian source rocks. The recent discovery of these hydrocarbons with two different sources in Wells ZS1 and ZS1 C suggests that both Middle-Upper Ordovician-sourced hydrocarbons and Cambrian-sourced petroleums are accumulated in the Tazhong Uplift, presenting a great exploration potential. 展开更多
关键词 Tazhong Uplift Wells ZS1 and ZS1C HYDROCARBON Organic geochemistry Oil/gas source identification
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CIECIA:A new climate change integrated assessment model and its assessments of global carbon abatement schemes 被引量:9
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作者 WANG Zheng GU Gao Xiang +1 位作者 WU Jing LIU Chang Xin 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第1期185-206,1-4,共22页
From the perspective of global economic general equilibrium, this study developed a new climate change IAM named CIECIA. The economic core of this IAM is a multi-country-sector general equilibrium model. The endogenou... From the perspective of global economic general equilibrium, this study developed a new climate change IAM named CIECIA. The economic core of this IAM is a multi-country-sector general equilibrium model. The endogenous technology progress mode is introduced into CIECIA. Based on this model, three assessment principles of the global cooperating abatement scheme are proposed, including effectiveness, feasibility, and fairness. This study simulated and analyzed six types of primary global cooperating abatement schemes. The simulated results indicate that all of the selected schemes can satisfy the climate mitigation targets by 2100. Thus, they are all effective schemes. However, the schemes have quite different feasibilities and fairness. The Stern Scheme benefits the developed countries, but is unfair to the developing countries. The Nordhaus Scheme promotes the developments of the developing countries. However, it leads to negative impacts on the interests of the developed countries. The principle of convergence on accumulated carbon emissions per capita and the principle of convergence on carbon emissions per capita benefit the economic developments of the middle and low developing countries most. However, these two types of schemes cause tremendous losses to the main economic entities in the world including China. The Pareto Improvement Scheme, which was developed from the Global Economic Growth Scheme, balances the fairness and feasibility in the carbon abatement process and realizes the Pareto improvement of accumulated utilities in all the participating countries. Thus, the Pareto Improvement Scheme is the most reasonable global cooperating carbon abatement scheme. 展开更多
关键词 Integrated assessment model Global cooperating abatement scheme General equilibrium Process technologicalprogress Pareto improvement
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Long-Term Effects of Inorganic and Organic Amendments on Organic Carbon in a Paddy Soil of the Taihu Lake Region,China 被引量:8
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作者 MA Li YANG Lin-Zhang +3 位作者 XIA Li-Zhong SHEN Ming-Xing YIN Shi-Xue LI Yun-Dong 《Pedosphere》 SCIE CAS CSCD 2011年第2期186-196,共11页
A long-term experiment set up in 1980 compared the effects of applying manures and chemical fertilizers on a paddy soil in the Taihu Lake region, China. Of the fourteen randomly distributed treatments consisting of di... A long-term experiment set up in 1980 compared the effects of applying manures and chemical fertilizers on a paddy soil in the Taihu Lake region, China. Of the fourteen randomly distributed treatments consisting of different combinations of organic manure, inorganic nitrogen (N), phosphorus (P), and potassium (K), and rice straw, eight were selected for the present study in 2007. Application of organic manure plus straw significantly increased soil organic carbon (SOC) content of the topsoil (0-10 cm) compared to that of chemical fertilizers alone. The content of SOC was relatively stable in the 10-30 cm layer in the chemical fertilizer treatments and in the 20-40 cm layer in the manure treatments. The stable carbon isotope ratio (513C) ranged from -24% to -28% and increased gradually with depth. The content of SOC was significantly (P 〈 0.05) negatively correlated with 513C. In the 0-20 cm layer, the 513C value significantly decreased in the treatments of manure alone (M), manure and chemical N and P fertilizers (MNP), manure and chemical N, P, and K fertilizers (MNPK), manure, rice straw, and chemical N fertilizer (MRN), and chemical N fertilizer and rice straw (CNR), as compared with the no-fertilizer control. In the 30-50 cm layer, however, the ratio significantly increased in all the treatments except Treatment CNR. Mineralization of organic C peaked in the first 2-4 d of incubation and gradually leveled off thereafter over the first 3 weeks, being faster in the manure treatments than the chemical fertilizer treatments. The average rate of mineralization varied from 55.36 to 75.46 mL CO2 kg-1 d-1 and that of stable mineralization from 10 to 20 mL CO2 kg-1 d-1. In eight weeks of incubation, cumulative mineralization was always higher in the manure treatments than the chemical fertilizer treatments, being the highest in Treatment MRN. Combined humus in the soil was mainly (over 50%) composed of tightly combined fraction. The loosely combined humus and its ratio of humic acid (HA) to fulvic acid (FA) significantly increased with long-term application of organic manure and chemical fertilizers. It could be concluded that the cycle of organic C in the paddy soil ecosystem studied was stable over the long-term application of fertilizers and continued cultivation. 展开更多
关键词 chemical fertilizer HUMUS MINERALIZATION organic manure stable carbon isotope ratio
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Self-referent phenotype matching and its role in female mate choice in arthropods
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作者 Carie B. WEDDLE John HUNT Scott K. SAKALUK 《Current Zoology》 SCIE CAS CSCD 2013年第2期239-248,共10页
A growing body of empirical evidence shows that females of many animal species gain benefits by mating polyan- drously, and often prefer to mate with novel males over previous mates. Although a female preference for n... A growing body of empirical evidence shows that females of many animal species gain benefits by mating polyan- drously, and often prefer to mate with novel males over previous mates. Although a female preference for novel males has been ,demonstrated for multiple animal taxa, the mechanisms used by females to discriminate between novel and previous mates remain largely unknown. However, recent studies suggest that in decorated crickets Gryllodes sigillatus, females actually imbue males with their own chemical cues, known as cuticular hydrocarbons (CHCs) during mating, and utilize chemosensory self-referencing 1:o recognize recent mates. Here we review evidence that self-referent phenotype matching is a widespread mechanism of recogni- tion in arthropods, and explore how CHCs are used to facilitate mate-choice decisions. There is substantial evidence that CHCs are used as recognition cues to discriminate between species, kin, sexes, mates, individuals, and self and non-self, and are used to facilitate mate-choice decisions in a wide range of arthropod taxa. There is also evidence that CHCs are often transferred between individuals during direct physical contact, including copulation. Chemosensory self-referencing via cuticular hydrocarbons could provide a simple, but reliable mechanism for identifying individuals from previous mating encounters. This mechanism does not require any specialized cognitive abilities because an individual's phenotype is always available for reference. Given the ubiqui- tous use of CHCs among arthropods, chemosensory self-referencing may be a widespread mechanism used by female arthropods to facilitate ibmale mate-choice decisions and to enhance opportunities for polyandry [Current Zoology 59 (2): 239-248, 2013]. 展开更多
关键词 POLYANDRY Chemical signals Cuticular hydrocarbons Sexual selection
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