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Effects of Lignite and Biochar on Enzyme Activity and Organic Carbon in Zn-contaminated Black Soil
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作者 Dai Jianjun Liu Zhaoting +1 位作者 Su Dezhen Wang Jingyi 《Journal of Northeast Agricultural University(English Edition)》 2025年第2期23-36,共14页
In order to explore the remediation effects of lignite and biochar on Zn-contaminated soil,this experiment studied the impacts of adding lignite and biochar on soil respiration,soil enzyme activity,and organic carbon ... In order to explore the remediation effects of lignite and biochar on Zn-contaminated soil,this experiment studied the impacts of adding lignite and biochar on soil respiration,soil enzyme activity,and organic carbon in Zn-contaminated soil through soil culture experiments,which provided a theoretical basis for the remediation and improvement as well as for the development and utilization of Zn-contaminated soil.The study was an L8(4×2^(2))orthogonal experimental design with eight treatments,in which there were four levels of Zn contamination concentration(Z0:0;Z1:125 mg•kg^(-1);Z2:250 mg•kg^(-1);Z3:500 mg•kg^(-1)),low-Zn(125-250 mg•kg^(-1))and high-Zn(500 mg•kg^(-1)),two levels of lignite(H0:0;H1:13.33 g•kg^(-1)),two levels of biochar(C0:0;C1:3.33 g•kg^(-1)),with four replicates per treatment.The results showed that lignite or biochar and their interaction had extremely significant effects on both respiration rate and accumulation in Zn-contaminated soil.Among the high Zn-contaminated treatments,the mixed application of lignite and biochar(Z3H1C1 treatment)had the fastest soil respiration rate and the highest soil respiration accumulation.Lignite,biochar and their interaction had significant or extremely significant effects on sucrase,catalase and polyphenol oxidase activities in Zn-contaminated soil.Among the high Zn-contaminated treatments(Z3),the addition of biochar alone had the most significant effects on the increase of soil sucrase and catalase enzyme activities,while the mixed application of lignite and biochar had the most significant effects on the increase of soil polyphenol oxidase activity.Lignite,biochar and their interaction had significant or extremely significant effects on the total organic carbon,active organic carbon and microbial carbon content of Zn-contaminated soils.Soil total organic carbon content in general peaked at day 80.Among the high Zn-contaminated treatments,the addition of biochar alone had the most significant effects on the total organic carbon content of the soil,while the mixed application of lignite and biochar had the most significant effect on the microbiomass carbon content. 展开更多
关键词 Zn pollution LIGNITE BIocHAR enzyme activity organic carbon
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Key Physical Factors Affecting Spatial-temporal Variation of Labile Organic Carbon Fractions by Biochar Driven in Mollisols Region of Northeast China
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作者 Zhao Wei Liang Fangyuan +4 位作者 Liang Ying Zhao Hongrui Hao Shuai Wang Hongyan Wang Daqing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期28-41,共14页
Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between phy... Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between physical properties and LOC fractions. A field positioning experiment was performed in Mollisols region of Northeast China to evaluate the influence of maize stalk biochar on the spatial distribution and temporal changes of physical properties and LOC fractions. Maize stalk biochar treatments included C1(1.5 kg·hm^(-2)), C2(3 kg·hm^(-2)), C3(15 kg·hm^(-2)), C4(30 kg·hm^(-2)), and CK(0). The results showed that maize stalk biochar increased soil water contents(SWC) and soil porosity(SP), but reduced bulk density(BD). Maize stalk biochar reduced dissolved organic carbon(DOC) contents in the 0-20 cm soil layer, ranging from 0.25 g·kg^(-1) to 0.31 g·kg^(-1) in harvest period, while increased in the 20-40 cm soil layer. In addition, the application of biochar had a significant impact on the spatial distribution and temporal change of SWC, BD, SP, DOC, hot-water extractable carbon(HWC), acid hydrolyzed organic carbon(AHC Ⅰ, Ⅱ), and readily oxidized organic carbon(ROC). High amounts of maize stalk biochar up-regulated the contents of soil organic carbon SOC, HWC, AHC Ⅰ, AHC Ⅱ, and ROC. In addition, SWC and SP were the key physical factors to affect LOC fractions. In conclusions, maize stalk biochar could improve physical properties, and then influence LOC fractions, and maize stalk biochar could be used as an organic amendment for restoring degraded soils governed by their rates of addition. 展开更多
关键词 maize stalk biochar labile organic carbon fraction Mollisols region soil physical property dissolved organic carbon
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Effect of organic carbon sources on the anodic corrosion of magnesium AZ31B by sulfate-reducing prokaryote
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作者 LI Jin-rong ZHANG Jie +6 位作者 KRISHNAMURTHY Mathivanan ZHU Qing-jun XING Shao-hua ZHANG Rui-yong SAND Wolfgang DUAN Ji-zhou HOU Bao-rong 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3369-3381,共13页
Corrosion caused by sulfate-reducing prokaryotes(SRP)is an important cause of magnesium alloy anode failure in oil pipeline.In this study,the effects of Desulfovibrio sp.HQM3 on the corrosion behavior of AZ31B magnesi... Corrosion caused by sulfate-reducing prokaryotes(SRP)is an important cause of magnesium alloy anode failure in oil pipeline.In this study,the effects of Desulfovibrio sp.HQM3 on the corrosion behavior of AZ31B magnesium alloy anode in organic carbon sources with different contents in simulated tidal flat environment were analyzed using weight loss test,surface analysis and electrochemical analysis technologies.The results showed that the weight loss rate of coupons in low carbon sources contents(0%,1%,10%)was higher than that in 100%carbon sources.Electrochemical analyses showed that the corrosion current density(J_(corr))under low carbon sources contents was larger,while the charge transfer resistance(R_(ct))was lower,leading to a higher corrosion rate compared to those under 100%carbon sources content.Observations from scanning electron microscopy(SEM)and confocal laser scanning microscopy(CLSM)revealed more severe pitting corrosion on the alloy surface in the absence of carbon sources.In addition,a large number of nanowires were observed between bacteria on the alloy surface using SEM.Combined with thermodynamic calculations,it was demonstrated that the corrosion of coupons by Desulfovibrio sp.HQM3 in the absence of carbon sources was achieved through extracellular electron transfer. 展开更多
关键词 AZ31B magnesium anode organic carbon source microbiologically influenced corrosion(MIC) sulfatereducing prokaryotes
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Adsorption of volatile organic compounds on three activated carbon samples:Effect of pore structure 被引量:11
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作者 李立清 宋剑飞 +3 位作者 姚小龙 黄贵杰 刘峥 唐琳 《Journal of Central South University》 SCIE EI CAS 2012年第12期3530-3539,共10页
To investigate the influence of the activated carbon pore structure on the adsorption of volatile organic compounds (VOCs), three commercial activated carbon samples were chosen. The fixed-bed thermostatic adsorptio... To investigate the influence of the activated carbon pore structure on the adsorption of volatile organic compounds (VOCs), three commercial activated carbon samples were chosen. The fixed-bed thermostatic adsorption experiments were conducted under certain conditions, where toluene, acetone, and 1, 2-dichloroethane acted as adsorbents. Then, the incidence relation between the experimental results and the activated carbon pore structure was analyzed. After that, the results of the correlation analysis were verified in accordance with fractal theory and adsorption characteristic curve analysis. The results show that the pore diameter gradient is helpful for strengthening the intemal diffusion. Under the same condition, the adsorption of organic gases tends to be selective, and the positions of toluene, acetone and 1, 2-dichloroethane adsorbed on the activated carbon are mainly in the ranges of 1.27-1.49 nm, 0.67-0.84 nm and 1.39-1.75 nm, respectively. The relationship between adsorption capacity and activated carbon pore volume can accurately explain the spreading process of the adsorbents in the activated carbon. 展开更多
关键词 activated carbon volatile organic compounds ADSORPTION pore structure SELECTIVITY
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Pool Sizes and Turnover of Soil Organic Carbon of Farmland Soil in Karst Area of Guilin 被引量:3
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作者 YANG Hui CAO Jianhua +2 位作者 ZHANG Liankai HOU Yanlin MAO Lifeng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第1期39-45,共7页
The three-pool and first-order model separates the mineralizable organic carbon into active,slow,and passive carbon pools.This paper used the model and decomposition curves of the soil organic carbon to fit the active... The three-pool and first-order model separates the mineralizable organic carbon into active,slow,and passive carbon pools.This paper used the model and decomposition curves of the soil organic carbon to fit the active pool and its decomposition rate,slow pool and its decomposition rate.The results showed that the size of the active pool from different profiles accounted for 2.09%-3.08% of the total soil organic carbon and the mean residue time was 3.57-17.21 days.And the size of the slow pool accounted for 3.19%-43.55% and the mean residue time was 1.12-4.94 years.Acid hydrolysis(6M HCl) was used to fractionate the passive organic carbon,which accounted for 50.83%-94.44% of the total soil organic carbon. 展开更多
关键词 karst area FARMLAND soil organic carbon pool turnover time
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Characteristics of soil organic carbon andtotal nitrogen storages for differentland-use types in Central Yunnan Plateau 被引量:1
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作者 SHEN Fangyuan TUO Yunfei +4 位作者 WANG Qian WANG Fei ZHENG Yang DU Wenjuan XIANG Ping 《排灌机械工程学报》 CSCD 北大核心 2022年第5期519-528,共10页
Two-factor analysis of variance and redundancy analysis were used to analyze the characte-ristics of soil organic carbon total nitrogen storage in garden land,forestland,grassland,farmland,and bare land in the Dachunh... Two-factor analysis of variance and redundancy analysis were used to analyze the characte-ristics of soil organic carbon total nitrogen storage in garden land,forestland,grassland,farmland,and bare land in the Dachunhe watershed of Jinning District,Kunming City,Yunnan Province,China.The effects of the soil organic carbon,total nitrogen stratification ratio,soil physical and chemical factors on the storage characteristics of organic carbon and total nitrogen of different land-use types were analyzed.The results show that the rates of carbon and nitrogen stratification in soil from 0-20 cm and 40-60 cm of the same land-use types differed are statistically significant(P<0.05).The organic carbon and total nitrogen stratification ratio SR1 of garden land soil are 38.5%and 25.3%,respectively,which are higher than SR^(2).The soil organic carbon and total nitrogen stratification ratio SR^(2) of different land-use types are greater than SR1.There are statistically significant differences in the SR^(2) soil organic carbon and total nitrogen stratification ratios(P<0.05).Soil organic carbon and total nitrogen storage of diffe-rent land-use types gradually decrease with increasing soil depth,with the maximum soil organic carbon and total nitrogen storage in the 0-20 cm soil layer.Soil organic carbon and total nitrogen sto-rage at the same soil depth are significantly different(P<0.05).Soil organic carbon and total nitrogen storage in the garden land are greater than those in the other land-use types.Soil organic carbon and total nitrogen storage in 0-20 cm garden land are 4.96 and 3.19 times than those in bare land,respectively;soil organic carbon and total nitrogen storage are explained by 93.66%and 1.53%in redundancy analysis RDA1 and RDA2,respectively.All physicochemical factors except Available Phosphorus and pH are statistically significance with carbon and nitrogen storage(P<0.05).Soil cationic exchange capacity,Available Phosphorus,C/N ratio,and Moisture Content are positively correlated with organic carbon and total nitrogen storage.In contrast,soil Bulk Density is negatively correlated with organic carbon storage and total nitrogen storage.Available Phosphorus,C/N ratio,and Moisture Content are the main factors promoting soil organic carbon and total nitrogen accumulation. 展开更多
关键词 soil organic carbon storage soil total nitrogen storage stratification ratio land-use types Central Yunnan Plateau
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基于卷积神经网络的页岩TOC三维定量预测方法
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作者 汪子祺 吴朝容 +3 位作者 黄开兴 孙正星 郝悦翔 李勇 《石油地球物理勘探》 北大核心 2025年第2期273-282,共10页
总有机碳含量(TOC)是页岩气勘探开发的一项重要评价指标。测井资料可高效评估TOC,但无法预测井间区域;而从地震资料提取的TOC敏感因子,可实现三维空间预测,但由于页岩储层的厚度薄且非均质性较强,仅依靠地震数据难以达到其精度要求。因... 总有机碳含量(TOC)是页岩气勘探开发的一项重要评价指标。测井资料可高效评估TOC,但无法预测井间区域;而从地震资料提取的TOC敏感因子,可实现三维空间预测,但由于页岩储层的厚度薄且非均质性较强,仅依靠地震数据难以达到其精度要求。因此需要综合使用多种数据以提升TOC评估准确性。为此,提出一种基于卷积神经网络的高精度页岩TOC定量预测方法。首先,针对页岩特性,对钻井实测岩心TOC数据与多种测井特征曲线进行相关性分析,优选出最具代表性和敏感性的特征;其次,基于识别出的敏感参数,构建相应的卷积神经网络预测模型,将实测TOC样本与敏感测井参数构建的训练样本按7∶3划分数据集,用于模型的训练和验证;最后,利用波形指示模拟技术获得的高分辨率敏感参数反演结果作为三维TOC含量预测的特征输入,将各敏感参数排列重组后输入卷积神经网络模型中,实现TOC含量的三维定量预测。研究结果表明,CNN在拟合TOC含量与敏感参数之间的非线性关系方面较多元回归法和BP神经网络等更具有优势,该方法预测的TOC数据与钻井实测值的平均绝对误差和均方根误差均小于0.6%,预测结果与实际情况一致。该方法在页岩薄储层三维TOC含量预测方面具有较高准确性和明显的优势。 展开更多
关键词 Toc含量 敏感参数 卷积神经网络 波形指示模拟
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我国汽车制造行业活性有机碳(ROC)排放研究
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作者 贾海洋 高美平 +2 位作者 聂磊 刘文文 魏巍 《中国环境科学》 北大核心 2025年第1期538-556,共19页
以汽车制造行业为对象,选取8家典型企业,采集109个涂料、胶粘剂等原辅料样品,检测其活性有机碳(ROC),建立汽车制造行业ROC源成分谱.通过最大增量反应活性法和二次产物的参数化产率法,量化样品中ROC对臭氧(O_(3))和SOA的生成贡献.结果表... 以汽车制造行业为对象,选取8家典型企业,采集109个涂料、胶粘剂等原辅料样品,检测其活性有机碳(ROC),建立汽车制造行业ROC源成分谱.通过最大增量反应活性法和二次产物的参数化产率法,量化样品中ROC对臭氧(O_(3))和SOA的生成贡献.结果表明:①不同类型原辅料中VOCs含量差异较大,水性和溶剂型汽车涂料平均ρ(VOCs)为289.92和490.32g/L;水性、本体型及溶剂型胶粘剂平均ρ(VOCs)为27.00,27.50和196.67g/L;水性和溶剂型清洗剂平均ρ(VOCs)为116.60和831.20g/L.②水性涂料的主要组分为醇醚及醚酯类、酯类和醇类,溶剂型涂料的主要组分为芳香烃、酯类和醇类,本体型胶粘剂和溶剂型胶粘剂的主要组分均为烷烃.③水性涂料中,各种类型有机物质量占比依次为SVOCs(36.03%)、IVOCs(37.77%)和VOCs(26.21%);溶剂型涂料中,主要为VOCs(95.41%),仅含少量IVOCs(4.59%),未检出SVOCs;本体型胶粘剂中仅检测出VOCs;溶剂型胶粘剂中,主要为VOCs(97.36%),含少量IVOCs(2.64%),未检出SVOCs.④水性涂料、溶剂型涂料、本体型胶粘剂和溶剂型胶粘剂中ROC的OFP值分别为93.67,2679.27,25.82和41.82g O_(3)/(L原辅料),首要贡献物种分别为二乙二醇丁醚(42.03%)、1,2,3-三甲苯(28.29%)、2,2,4,6,6-五甲基庚烷(52.20%)和2,2,4,6,6-五甲基庚烷(78.63%).⑤水性涂料、溶剂型涂料、本体型胶粘剂和溶剂型胶粘剂中ROC的SOA值分别为18.49,16.70,4.82和4.28g SOA/(L原辅料),水性涂料中IVOCs和SVOCs物种对SOA生成贡献率最高;溶剂型涂料及胶粘剂中VOCs物种对SOA生成贡献率最高.⑥本研究加入IVOCs和SVOCs物种对SOA生成贡献的评估后,发现单位体积水性涂料所生成的SOA值高于溶剂型涂料和胶粘剂,应在污染防治政策制定中重视水性涂料中SVOCs和IVOCs对大气环境的影响. 展开更多
关键词 汽车制造行业 活性有机碳(Roc) 中等挥发性有机物(IVocs) 半挥发性有机化合物(SVocs) 成分谱 环境影响
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Water vapor adsorption in activated carbon modified with hydrophilic organic salts
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作者 姚小龙 李立清 +1 位作者 李海龙 池东 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期478-486,共9页
Five different kinds of hydrophilic organic salts were used to modify commercial activated carbon in order to prepare hydrophilic carbon materials. Properties of the samples were analyzed by surface area analyzer and ... Five different kinds of hydrophilic organic salts were used to modify commercial activated carbon in order to prepare hydrophilic carbon materials. Properties of the samples were analyzed by surface area analyzer and SEM-EDX. The hydrophilic organic salts with different properties were introduced into activated carbon and significantly affected the properties of the samples.During adsorption experiments, the water vapor adsorption amount in modified samples increases by 0.57-17.12 times in temperature range from 303 to 323 K and at relative pressure below 0.50. Water molecules combined with surface hydrophilic groups through H-bonding exhibit good thermo stability. The effects of temperature, oxygen content and properties of the hydrophilic organic salts on water vapor adsorption were studied. It is indicated that water vapor adsorption in modified samples is mainly affected by the surface oxygen content. The carboxylate radicals in the hydrophilic organic salts greatly affect the micropore structure of the modified samples, while the metal ions in them exhibit limited influence. Different adsorption capacity of modified samples can be explained with the electronegativity of elements presented by Pauling. 展开更多
关键词 water vapor ADSORPTION activated carbon MODIFICATION hydrophilic organic salts
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Distribution of soil water-stable aggrega-tes and organic carbon content affected by tillage systems:a meta-analysis
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作者 LU Xingli LI Shanshan +4 位作者 LIU Jihu DUAN Yaxin YUE Heng KANG Jianhong WU Hongliang 《排灌机械工程学报》 CSCD 北大核心 2021年第10期1051-1055,共5页
A better understanding of soil carbon(C)distribution within aggregate fractions is essential to evaluating the potential of no-till for sustaining productivity and protecting the environment.A meta-analysis on 744 com... A better understanding of soil carbon(C)distribution within aggregate fractions is essential to evaluating the potential of no-till for sustaining productivity and protecting the environment.A meta-analysis on 744 comparisons from 34 studies was conducted to determine the effects of three different tillage treatments(conventional mouldbould ploughing tillage(CT),reduced tillage(RT)and no tillage(NT))on water-stable aggregate size distribution,soil C concentration in aggregate fractions.The meta-analysis indicates that compared with CT treatment,NT/RT significantly(P<0.05)increases macro-aggregate above 20 cm by 20.9%-82.2%(>2.00 mm)and 5.9%-19.1%(0.25-2.00 mm),whereas NT/RT significantly reduces micro-aggregate and silt clay fractions above 20 cm.NT/RT significantly(P<0.05)increases the SOC in macro-aggregate(>0.25 mm)and micro-aggregate(<0.25 mm)size classes above 20 cm soil depth compared with CT.The results suggest that soil sampling depth should be considered to evaluate the influence of tillage systems on the distribution of soil aggregate,and the content of aggregate-associated C content. 展开更多
关键词 soil aggregation soil organic carbon reduced tillage soil depth
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Organic Fuel Synthesis from Atmospheric Carbon Dioxide and Hydrogen Produced from Water by Electrolysis
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作者 David JOHNSTON 《电工电能新技术》 CSCD 北大核心 2009年第3期6-10,66,共6页
Synthesis of organic fuels from carbon dioxide and hydrogen is analysed,in terms of energy recovery efficiency,and the required energy input for electrolysis of water.This electrical energy is related to the thermal e... Synthesis of organic fuels from carbon dioxide and hydrogen is analysed,in terms of energy recovery efficiency,and the required energy input for electrolysis of water.This electrical energy is related to the thermal energy required in a power station.A method is described to recover heat from energy-producing reactions in the fuel synthesis process,which can then be used to reduce the electrical energy requirement for electrolysis.By co-locating the fuel synthesis plant with a thermal power station,primary(thermal) energy can be used to produce high temperature steam,with a lower electrical requirement for electrolytic production of hydrogen.This can make more efficient use of the primary energy than a thermodynamic engine.Comparison is made with alternative fuels,in terms of energy budget,sustainability,carbon dioxide emissions,etc.The energy security benefits of advanced fuel synthesis are also identified. 展开更多
关键词 燃料 二氧化碳 电解
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藏东南高山林线带5种植被类型SOC分布特征及其与土壤物理性质的关系
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作者 高鑫 万丹 +6 位作者 王君惠 周金龙 李超 杨来仙 刘钟元 骆师堂 张娟 《西南农业学报》 北大核心 2025年第3期612-619,共8页
【目的】探明高山林线带5种植被类型下土壤有机碳(SOC)/土壤有机碳密度(SOCD)分布特征及其与土壤物理性质的相关性,以便明确SOC含量对植被类型和土壤物理性质的响应特征。【方法】以藏东南超高海拔区色季拉山为研究区域,选取高山林线带... 【目的】探明高山林线带5种植被类型下土壤有机碳(SOC)/土壤有机碳密度(SOCD)分布特征及其与土壤物理性质的相关性,以便明确SOC含量对植被类型和土壤物理性质的响应特征。【方法】以藏东南超高海拔区色季拉山为研究区域,选取高山林线带5种植被类型(高山草甸、草灌过渡带、灌木林、乔灌过渡带、乔木林),按照0~20、20~40、40~60 cm土层深度分层取样,分别测定SOC、容重(SBD)及通气度(SAP)等物理性质指标,探究5种植被类型SOC含量及沿土层深度分布特征,并分析SOC/SOCD与土壤物理性质之间的关系。【结果】(1)5种植被类型下,SOC与SOCD平均变化范围为49.62~85.02 g/kg与10.33~13.23kg/m^(2),其中乔灌过渡带SOC含量最高;沿土层深度从上至下SOC均值分别为85.02、57.80、49.62 g/kg,SOCD均值分别为13.23、11.63、10.33 kg/m^(2),表层SOC含量最高,随着土层深度的增加而减少;(2)不同植被类型下、不同土层深度的土壤物理性质差异极显著(P<0.01,下同),土壤物理性质受到植被类型和土层深度的影响;(3)在土层深度条件下,SOC与SAP呈极显著负相关,与SCP呈显著负相关(P<0.05),在植被类型条件下,SOC与CWC、STP、SAP呈极显著正相关。SOCD与土壤物理性质基本不相关(P>0.05)。【结论】不同植被类型下SOC含量有显著差异。植被类型对SOC的分布有明显影响,植被类型越复杂的区域SOC含量越高。SOC主要与SAP有密切相关性,其分布于表层土壤,有明显的表聚特征。 展开更多
关键词 土壤有机碳 土壤物理性质 植被类型 相关性分析
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提高煤系页岩储层TOC计算精度的改进方法 被引量:2
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作者 李梦蕾 张超谟 +3 位作者 石文睿 周雪晴 虞成 罗意淳 《石油物探》 CSCD 北大核心 2024年第4期817-825,共9页
总有机碳含量(TOC)是决定烃源岩质量的最重要参数。为了准确评价煤系页岩气储层的TOC参数,以四川盆地Q区龙潭组C1井海陆过渡相页岩气储层为例,对提高储层TOC参数计算精度的方法进行了研究。根据研究区的地质特点,结合自然伽马能谱测井数... 总有机碳含量(TOC)是决定烃源岩质量的最重要参数。为了准确评价煤系页岩气储层的TOC参数,以四川盆地Q区龙潭组C1井海陆过渡相页岩气储层为例,对提高储层TOC参数计算精度的方法进行了研究。根据研究区的地质特点,结合自然伽马能谱测井数据,对原始Δlog R方法进行改进,形成了基于自然伽马能谱测井的双Δlog R方法。首先,将岩心TOC数据按岩性分为煤层和非煤层,然后,将自然伽马能谱测井数据(钍钾比(Th/K)和钍铀比(Th/U))分别与煤层TOC和非煤层TOC进行相关性分析,各自选择最高相关性的数据与Δlog R拟合,计算煤层和非煤层的TOC。结果表明,基于自然伽马能谱测井的双Δlog R方法和传统方法相比,C1井煤层和非煤层TOC计算相关性最高可以提高到0.78和0.85,煤层和非煤层TOC的绝对误差最低都可以降到0.01%,煤层和非煤层TOC的相对误差降低到14.93%和12.53%。将基于自然伽马能谱测井的双Δlog R方法应用于四川盆地S区Y组C2井,取得了较好的效果。改进的方法适用于研究区页岩气储层黏土含量高,非均质性强,且存在黑色煤层的页岩储层,有效弥补TOC与铀(U)含量无明显相关性的不足,具有较好的适用性和推广性,可以有效辅助研究区页岩气储层的勘探开发。 展开更多
关键词 总有机碳含量 页岩气 煤系页岩 页岩储层 四川盆地 海陆过渡相
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Candidate organic electrolytes for electric double-layer capacitor application
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作者 B.Fang Y.Wei +1 位作者 K.Suzuki M.Kumagai 《电池》 CAS CSCD 北大核心 2004年第5期337-339,共3页
Electrolytic conductivity, viscosity and electrochemical behavior were investigated for organic electrolytes based on PC(Propylene carbonate), MAN(Methoxy acetonitrile) and GBL(γ-Butyrolactone) solvents. It was... Electrolytic conductivity, viscosity and electrochemical behavior were investigated for organic electrolytes based on PC(Propylene carbonate), MAN(Methoxy acetonitrile) and GBL(γ-Butyrolactone) solvents. It was found that 1 mol/L Et4NBF4-MAN had the highest conductivity, lowest viscosity and acceptable potential window. The specific capacitance and energy density obtained from the capacitor using 1 mol/L Et4NBF4-MAN as electrolyte were the highest among all the tested electrolytes.(1 mol/L) Et4NBF4-GBL also seemed promising to be used in electric double-layer capacitor (EDLCs). 展开更多
关键词 EDLC CBC EIS 电容器
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Corrosion behavior of B10 copper-nickel alloy beneath a deposit caused by sulfate-reducing bacteria with carbon source starvation in marine environments
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作者 JIN Zheng-yu WANG Zhi +7 位作者 FAN Yu-xing LIU Hai-xian LIU Ruo-ling ZHANG Yi YIN Yan-sheng LIU Hong-fang FAN Shao-jia LIU Hong-wei 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3382-3393,共12页
Copper-nickel alloys can suffer severe localized corrosion in marine environments containing sulfate-reducing bacteria(SRB),but the effect of SRB on the under-deposit corrosion of copper-nickel alloys is unknown.In th... Copper-nickel alloys can suffer severe localized corrosion in marine environments containing sulfate-reducing bacteria(SRB),but the effect of SRB on the under-deposit corrosion of copper-nickel alloys is unknown.In this work,the corrosion behavior of B10 copper-nickel alloy beneath a deposit caused by SRB with carbon source starvation in artificial seawater was studied based on electrochemical measurements and surface analysis.Results demonstrate that SRB with an organic carbon starvation can survive in artificial water but most SRB cells have died.The survived SRB cells can attach to the bare and deposit-covered B10 copper-nickel alloy,leading to the corrosion acceleration.Due to the limitation of organic carbon source,the pitting corrosion of B10 copper-nickel alloy caused by SRB is not serious.However,serious pitting corrosion of the deposit-covered B10 copper-nickel alloy can be found both in abiotic and biotic conditions,and the pitting corrosion and uniform corrosion are further accelerated by SRB.There is a galvanic effect between the bare and deposit-covered specimens in the presence of SRB in the early stage but the galvanic effect after 5 d of testing can be neglected due to the low OCP difference values. 展开更多
关键词 sulfate-reducing bacteria copper-nickel alloys microbiologically influenced corrosion under-deposit corrosion pitting corrosion organic carbon starvation
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基于3DEEM-PARAFAC方法对不同秸秆还田方式下WSOC的组分与荧光特征分析
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作者 王楠楠 孙冬梅 李玉梅 《黑龙江八一农垦大学学报》 2024年第2期15-22,共8页
以三维荧光光谱结合平行因子法(3DEEM-PARAFAC)为主要分析方法,分析秸秆未还田条件下3种耕作方法(免耕、浅翻、深翻)及相应还田方法(秸秆免耕覆盖、浅翻还田、深翻还田)下,土壤水溶性有机碳(WSOC)的组分及不同土层的荧光特性。结果表明... 以三维荧光光谱结合平行因子法(3DEEM-PARAFAC)为主要分析方法,分析秸秆未还田条件下3种耕作方法(免耕、浅翻、深翻)及相应还田方法(秸秆免耕覆盖、浅翻还田、深翻还田)下,土壤水溶性有机碳(WSOC)的组分及不同土层的荧光特性。结果表明,土壤WSOC解析出4个荧光组分,分别为2个类腐殖质物质C1(310,240/410 nm)、C2(270/465 nm)和两个类蛋白物质C3(280,230/340 nm)、C4(220/300 nm);秸秆深翻还田在>35 cm土层有不同程度的促进类腐殖华物质C1、C2组分向类蛋白物质C4组分转化的趋势;土壤WSOC的来源均为植物源与微生物源的混合贡献,深翻还田在>35 cm土层腐殖化程度最低。秸秆还田与深翻对深层土壤WSOC中结构较为复杂、芳香性高的有机物的矿化分解有一定促进作用。 展开更多
关键词 水溶性有机碳(WSoc) 耕作方法 秸秆还田 3DEEM-PARAFAC
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滴灌下肥料管理对小麦产量和碳氮足迹的影响 被引量:1
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作者 邢素丽 王敬霞 +8 位作者 杨军芳 黄少辉 聂浩亮 张静 杨慧敏 杨文方 杨云马 王磊 贾良良 《农业工程学报》 北大核心 2025年第2期103-111,共9页
为解决小麦生产中氮肥投入过量及灌溉不合理问题,提出华北平原小麦绿色高产生产技术,为农业可持续发展提供支撑。该试验以冬小麦为研究对象,设置滴灌不施肥(D-0)、滴灌不施氮肥(D-N0)、畦灌常规施肥(Q-FP)、滴灌优化施肥(D-NPK)、滴灌... 为解决小麦生产中氮肥投入过量及灌溉不合理问题,提出华北平原小麦绿色高产生产技术,为农业可持续发展提供支撑。该试验以冬小麦为研究对象,设置滴灌不施肥(D-0)、滴灌不施氮肥(D-N0)、畦灌常规施肥(Q-FP)、滴灌优化施肥(D-NPK)、滴灌有机无机配施(D-NPKM)处理,研究不同措施对小麦产量、碳氮足迹及农田净生态经济效益的影响。结果表明:氮肥和灌溉方式是小麦产量的关键制约因素,与Q-FP处理相比,同时优化施肥及灌溉方式(D-NPK),小麦产量和收获指数平均分别显著提高12.3%和13.2%,D-NPKM处理可显著提高小麦产量和收获指数16.8%和13.1%。相比于畦灌农户常规施肥,滴灌条件下优化施肥量(D-NPK)及有机无机配施(D-NPKM)是小麦生产系统碳氮排放及环境足迹降低的有效措施,氮足迹分别降低61.7%和59.8%,碳足迹分别降低44.5%和25.3%。滴灌模式下,有机无机配施(D-NPKM)处理氮足迹和碳足迹均高于单施化肥(D-NPK)处理,分别高4.9%和34.6%,而净生态经济效益降低于D-NPK处理24.3%。因此,从小麦生产力角度来看,滴灌结合有机无机配施是最优化措施,但结合生态环境角度,建议D-NPK处理为最优化措施。整体来看,在该研究试验条件下,推荐滴灌结合肥料减量措施作为小麦生产的最优化措施,但相比于农户常规灌溉施肥,滴灌下有机无机配施仍是提高小麦生产力,降低小麦生产碳氮足迹的有效措施,未来可结合不同地区有机肥资源进行综合考虑,选择可进一步降低碳足迹的有机肥类型及施用方式,以最大化资源利用,实现农业可持续发展。 展开更多
关键词 小麦 滴灌 有机肥 产量 碳氮足迹
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活性炭对铜绿微囊藻胞外有机物的吸附规律 被引量:1
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作者 孙凤 吴磊 +4 位作者 叶硕 邓鑫 张朝阳 王彤 丛海兵 《中国环境科学》 北大核心 2025年第3期1546-1555,共10页
重点考察了粉末活性炭对不同生长期铜绿微囊藻溶解性胞外有机物(EOM)的吸附去除效果,探究活性炭对不同时期铜绿微囊藻EOM特征性有机组分的去除率及吸附规律.结果发现,粉末活性炭对铜绿微囊藻EOM的有机组分协同去除率较低,仅为18.07%~34.... 重点考察了粉末活性炭对不同生长期铜绿微囊藻溶解性胞外有机物(EOM)的吸附去除效果,探究活性炭对不同时期铜绿微囊藻EOM特征性有机组分的去除率及吸附规律.结果发现,粉末活性炭对铜绿微囊藻EOM的有机组分协同去除率较低,仅为18.07%~34.85%,且对EOM中的不同物质组分呈现藻毒素>腐殖酸>蛋白质>多糖的明显吸附率差异.各物质组分在不同生长时期具有不同的易吸附型结构占比,因此导致不同时期吸附量也存在一定差异性.多糖中易吸附结构主要释放于对数期,蛋白质中易吸附结构多分泌于稳定期,藻毒素中多分泌于稳定期和衰亡期,而腐殖酸在各时期的结构类型占比差异并不显著.活性炭对铜绿微囊藻EOM的吸附过程遵循分子尺度选择吸附原则,以中低分子量物质为主,对高分子量物质吸附性极差,这也是导致活性炭对藻源污染物去除率低下的重要因素.本研究对于蓝藻爆发全周期藻源污染物的有效防控具有重要的科学意义. 展开更多
关键词 铜绿微囊藻 胞外有机物 活性炭 吸附
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绿肥部分替代化肥氮对土壤物理性状的影响 被引量:1
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作者 秦文利 张静 +10 位作者 肖广敏 崔素倩 叶建勋 智健飞 张立锋 谢楠 冯伟 刘振宇 潘璇 代云霞 刘忠宽 《草业学报》 北大核心 2025年第6期27-45,共19页
2020-2022年度以毛叶苕子和玉米为材料,采用二因素裂区田间试验设计,主处理为冬闲田(FF)、冬闲田种植毛叶苕子并全量还田(HV)2种模式,副处理为玉米0(0N)、135.0(50%N)和270.0 kg·hm^(-2)(100%N)3个施氮水平,研究了毛叶苕子还田和... 2020-2022年度以毛叶苕子和玉米为材料,采用二因素裂区田间试验设计,主处理为冬闲田(FF)、冬闲田种植毛叶苕子并全量还田(HV)2种模式,副处理为玉米0(0N)、135.0(50%N)和270.0 kg·hm^(-2)(100%N)3个施氮水平,研究了毛叶苕子还田和施氮水平对玉米0~10 cm、10~20 cm土层土壤团聚体组成与分布、团聚体平均重量直径(MWD)、几何平均直径(GMD)、破坏率(PAD)、可蚀性因子(K)、容重(BD)、总孔隙度(TP)、毛管孔隙度(CP)、非毛管孔隙度(NCP)、最大持水量(MWHC)、毛管持水量(CWHC)、非毛管持水量(NCWHC)、土壤有机碳(SOC)含量、团聚体有机碳(AOC)含量及玉米产量的影响,以期从土壤物理性状变化为绿肥部分替代化肥氮实现作物稳产增产提供科学依据。结果表明,与FF模式相比,HV模式0~10 cm、10~20 cm土层>0.25 mm水稳定性团聚体总含量(R0.25)、MWD、GMD、TP、CP、NCP、MWHC、CWHC、NCWHC、SOC含量分别显著增加8.95%、40.84%、30.57%、5.89%、1.47%、4.42%、15.01%、6.41%、27.08%、7.29%和13.13%、62.87%、51.68%、5.02%、0.76%、4.25%、13.11%、3.32%、27.86%、7.10%;PAD、K和BD分别显著降低8.83%、20.79%、5.99%和12.14%、30.73%、7.31%。HV模式下各土层各粒径AOC含量及玉米产量均显著提高。施氮水平对各土层各粒径AOC含量、R0.25及其他物理性状指标、玉米产量影响显著或极显著。HV模式50%N处理0~10 cm、10~20 cm土层的SOC含量、>5 mm AOC含量及0~10 cm土层的0.50~1.00 mm AOC含量、10~20 cm土层的BD、TP、CP、NCP、MWD、CWHC、NCWHC及玉米产量较FF模式100%N处理变化均不显著,0~10 cm、10~20 cm土层的2.00~5.00 mm、1.00~2.00 mm、0.25~0.50 mm、<0.25 mm AOC含量及10~20 cm土层0.50~1.00 mm的AOC含量,0~10 cm、10~20 cm土层的R0.25、MWD、GMD,0~10 cm土层的TP、NCP、MWHC、NCWHC均显著提高,0~10 cm、10~20 cm土层的PAD、K及0~10 cm土层的BD均显著下降。各粒径AOC含量与SOC含量之间、各粒级团聚体含量与其AOC含量之间、土壤物理性状指标与各粒级团聚体含量之间、玉米产量与土壤物理性状指标之间均呈显著或极显著相关。因此,绿肥还田后土壤有机碳含量的提高是促进团粒结构形成,增强土壤抗侵蚀、持水能力的重要基础。绿肥对土壤氮、有机碳的输入是其部分替代氮肥、改善土壤物理性状、实现减氮增产的重要前提。 展开更多
关键词 毛叶苕子 施氮水平 土壤有机碳含量 土壤物理性状 玉米产量
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长期增施有机肥对土壤物理特征、微生物生物量碳氮及土壤酶活性的影响
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作者 杨永辉 张运红 +5 位作者 高翠民 刘昊 潘晓莹 何方 韩伟锋 武继承 《干旱地区农业研究》 北大核心 2025年第3期107-115,共9页
增施有机肥对改善土壤结构、提高土壤保水保肥能力,提升微生物活性和土壤质量均具有重要作用,但长期增施有机肥对土壤物理特性、水分参数、微生物特性及其相互关系尚不清楚,需要系统研究以确定长期施用有机肥对于土壤理化特性及其生物... 增施有机肥对改善土壤结构、提高土壤保水保肥能力,提升微生物活性和土壤质量均具有重要作用,但长期增施有机肥对土壤物理特性、水分参数、微生物特性及其相互关系尚不清楚,需要系统研究以确定长期施用有机肥对于土壤理化特性及其生物特性的综合作用效果。本研究在河南省节水农业禹州试验基地开展长期定位试验(2006年小麦播种时开始),采用CT扫描技术定量分析长期施用有机肥(腐熟鸡粪750 kg·hm^(-2))对0~40 cm土层土壤孔隙的影响,同时测定分析0~10 cm土层的土壤团粒结构、土壤水分参数及微生物生物量碳氮和土壤酶活性等指标。结果表明:随着土壤团聚体粒级的减小,不同施肥措施的土壤团聚体含量表现为逐渐增加的趋势。与单施化肥相比,增施有机肥的>0.5 mm粒级的团聚体含量提高了70.1%,0.25~0.5 mm和<0.25 mm粒级的团聚体含量分别减少了34.2%和26.5%;增施有机肥提高了水稳性大团聚体含量和团聚体平均重量直径,提高了土壤结构稳定性。随土层的加深,土壤孔隙数目呈现逐渐增加的趋势,土壤孔隙度则表现为逐渐降低的趋势,土壤孔隙成圆率则表现为逐渐增加再降低的趋势。长期增施有机肥提高了0~100 mm、200~250 mm和250~300 mm土层的孔隙数目,0~100 mm、150~200 mm和250~400 mm土层的土壤孔隙度以及0~150 mm和155~200 mm土层的孔隙成圆率;长期增施有机肥可提高土壤饱和导水率、土壤持水能力、供水能力、田间持水量及有效水含量,且提高了小麦不同生育时期的土壤微生物生物量碳和氮、土壤蔗糖酶、纤维素酶、脲酶及蛋白酶活性。综上所述,长期增施有机肥改善了土壤理化性质、提高了土壤结构稳定性和土壤水分参数,同时提高了微生物活性和土壤酶活性。 展开更多
关键词 有机肥 土壤结构 土壤有机碳 土壤水分参数 土壤微生物生物量碳氮 土壤酶活性
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