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Responses of Soil Microbial Community Structure and Activity to Incorporation of Straws and Straw Biochars and Their Effects on Soil Respiration and Soil Organic Carbon Turnover 被引量:8
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作者 TIAN Xiaoping WANG Lei +3 位作者 HOU Yahong WANG Han TSANG Yiu Fai WU Jihua 《Pedosphere》 SCIE CAS CSCD 2019年第4期492-503,共12页
Like straw, biochar incorporation can influence soil microorganisms and enzyme activities and soil carbon(C) responses;however,few studies have compared the various effects of straw and biochar and the underlying mech... Like straw, biochar incorporation can influence soil microorganisms and enzyme activities and soil carbon(C) responses;however,few studies have compared the various effects of straw and biochar and the underlying mechanisms. An experiment was performed to study the changes in soil respiration(SR) and soil organic C(SOC) fluxes in response to the incorporation of three kinds of straw(reed, smooth cordgrass, and rice) and their pyrolyzed products(biochars) at Chongming Island, China. In addition, the microbial activity and community structure of some amended soils were also analyzed to clarify the mechanisms of these responses. The results showed that all biochar incorporation(BC) induced lower SR than the corresponding unpyrolyzed straw incorporation(ST), and the average SR in the soils following BC and ST during the experimental periods was 21.69 and 65.32 μmol CO2 m^-2s^-1, respectively.Furthermore, the average SOC content was 16.97 g kg-1 following BC, which was higher than that(13.71 g kg-1) following ST,indicating that compared to ST, BC was a low-C strategy, even after accounting for the C loss during biochar production. Among the BC treatments, reed-BC induced the lowest SR(17.04 μmol CO2 m^-2s^-1), whereas smooth cordgrass-BC induced the highest SR(27.02 μmol CO2 m^-2s^-1). Furthermore, in contrast with ST, BC significantly increased the abundance of some bacteria with poorer mineralization or better humification ability, which led to lower SR. The lower easily oxidizable C(EOC) and higher total C contents of biochars induced lower SR and higher SOC in the soil following BC compared to that following ST. Among the BC treatments,the higher total nitrogen content of rice biochar led to significantly higher soil microbial biomass, and the lower EOC content of reed biochar led to lower soil microbial activity and SR. 展开更多
关键词 easily oxidizable CARBON SOIL fertility SOIL MICROBIAL abundance SOIL MICROBIAL biomass SOIL MICROBIAL diversity SOIL organic CARBON decomposition
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Land use effects on soil organic carbon, nitrogen and salinity in saline-alkaline wetland 被引量:6
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作者 WenJie Liu YongZhong Su Rong Yang XueFengWang XiaoYang 《Research in Cold and Arid Regions》 2010年第3期263-270,共8页
Land-use and soil management affects soil organic carbon (SOC) pools, nitrogen, salinity and the depth distribution. The objective of this study was to estimate land-use effects on the distribution of SOC, labile fr... Land-use and soil management affects soil organic carbon (SOC) pools, nitrogen, salinity and the depth distribution. The objective of this study was to estimate land-use effects on the distribution of SOC, labile fractions C, nitrogen (N) and salinity in saline-alkaline wetlands in the middle reaches of the Heihe River Basin. Three land-use types were selected: intact saline-alkaline meadow wetland, artificial shrubbery (planting Tamarix) and farmland (cultivated for 18 years) of soils previously under meadow wetland. SOC, easily oxidized carbon, microbial biomass carbon, total N, NO3--N and salinity concentrations were measured. The results show that SOC and labile fraction carbon contents decreased significantly with increasing soil depth in the three land-use wetlands. The labile fraction carbon contents in the topsoil (0-20cm) in cultivated soils were significantly higher than that in intact meadow wetland and artificial shrubbery soil. The aboveground biomass and soil permeability were the primary influencing factors on the contents of SOC and the labile carbon in the intact meadow wetland and artificial shrubbery soil, however, the farming practice was a factor in cultivated soil. Agricultural measures can effectively reduce the salinity contents; however, it caused a significant increase of NO 3--N concentrations which posed a threat to groundwater quality in the study area. 展开更多
关键词 labile fraction carbon easily oxidized carbon microbial biomass carbon salinity nitrate-nitrogen saline-alkaline wetland
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Soil organic carbon pool along different altitudinal level in the Sygera Mountains, Tibetan Plateau 被引量:6
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作者 MA He-ping YANG Xiao-lin +2 位作者 GUO Qi-qiang ZHANG Xin-jun ZHOU Chen-ni 《Journal of Mountain Science》 SCIE CSCD 2016年第3期476-483,共8页
Labile organic carbon(LOC) is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the s... Labile organic carbon(LOC) is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the sources and causes of LOC contamination are. In this study, soil organic carbon(SOC), total nitrogen(TN), microbial biomass carbon(MBC), microbial biomass nitrogen(MBN) and LOC were analyzed based on different soil horizons and elevations using turnover time in an experimental site(3700 m to 4300 m area) in Sygera. SOC and LOC in higher-elevation vegetation types were higher than that of in lower-elevation vegetation types. Our results presented that the soil microbial biomass carbon(SMBC) and soil microbial biomass nitrogen(SMBN)were positively correlated with SOC. The content of easily oxidized carbon(EOC), particulate organic carbon(POC) and light fraction organic carbon(LFOC) decreased with depth increasing and the content were the lowest in the 60 cm to 100 cm depth.The total SOC, ROC and POC contents decreased with increasing soil horizons. The SOC, TN, MBC and MBN contents increased with increasing altitude in the Sygera Mountains. The MBC and MBN contents weredifferent with the changes of SOC(p&lt;0.05),meanwhile, both LFOC and POC were related to total SOC(p&lt;0.05). The physical and chemical properties of soil, including temperature, humidity, and altitude,were involved in the regulation of SOC, TN, MBC,MBN and LFOC contents in the Sygera Mountains,Tibetan Plateau. 展开更多
关键词 Labile soil organic easily oxidized carbon KMn O_4 Light fraction organic carbon Particulate organic carbon
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Alterations of soil aggregates and intra-aggregate organic carbon fractions after soil conversion from paddy soils to upland soils:Distribution,mineralization and driving mechanism
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作者 Longfei KANG Jiamei WU +2 位作者 Chunfeng ZHANG Baoguo ZHU Guixin CHU 《Pedosphere》 SCIE CAS CSCD 2024年第1期121-135,共15页
Investigating the impacts of soil conversion on soil organic carbon(OC) content and its fractions within soil aggregates is essential for defining better strategies to improve soil structure and OC sequestration in te... Investigating the impacts of soil conversion on soil organic carbon(OC) content and its fractions within soil aggregates is essential for defining better strategies to improve soil structure and OC sequestration in terrestrial ecosystems. However, the consequences of soil conversion from paddy soil to upland soil for soil aggregates and intra-aggregate OC pools are poorly understood. Therefore, the objective of this study was to quantify the effects of soil conversion on soil aggregate and intra-aggregate OC pool distributions. Four typical rice-producing areas were chosen in North and South China, paired soil samples(upland soil converted from paddy soil more than ten years ago vs. adjacent paddy soil) were collected(0–20 cm) with three replicates in each area. A set of core parameters(OC preservation capacity, aggregate carbon(C) turnover, and biological activity index) were evaluated to assess the responses of intra-aggregate OC turnover to soil conversion. Results showed that soil conversion from paddy soil to upland soil significantly improved the formation of macro-aggregates and increased aggregate stability. It also notably decreased soil intra-aggregate OC pools, including easily oxidized OCa(EOCa), particulate OCa(POCa), and mineral-bound(MOCa) OC, and the sensitivity of aggregate-associated OC pools to soil conversion followed the order: EOCa(average reduction of 21.1%) > MOCa(average reduction of 15.4%) > POCa(average reduction of 14.8%). The potentially mineralizable C(C_(0)) was significantly higher in upland soil than in paddy soil, but the corresponding decay constant(k) was lower in upland soil than in paddy soil. Random forest model and partial correlation analysis showed that EOCa and pH were the important nutrient and physicochemical factors impacting k of C mineralization in paddy soil,while MOCa and C-related enzyme(β-D-cellobiohydrolase) were identified as the key factors in upland soil. In conclusion, this study evidenced that soil conversion from paddy soil to upland soil increased the 展开更多
关键词 decay constant easily oxidized organic C macro-aggregate meso-aggregate MICRO-AGGREGATE mineral-bound organic C particulate organic C potentially mineralizable C
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N-氨基甲酰基-1-(3,5-二氯苯基)-3-羟基-6,6-二甲基-2,4-二氧-2,3,4,5,6,7-六氢-1H-吲哚-3-甲酰胺的简便合成和结构表征 被引量:3
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作者 朱晓彤 吴楠 +2 位作者 张荣丽 刘永民 姜波 《分子科学学报》 CAS CSCD 北大核心 2013年第3期177-182,共6页
标题化合物(C18H17Cl2N3O5)以阿脲水合物和N-3,5-二氯苯基烯胺酮为原料,在醋酸溶剂中,室温下经搅拌合成得到.其结构通过单晶X射线衍射法确定,晶体属单斜晶系,空间群P21/c,相对分子质量Mr=426.25,晶胞参数a=1.018 11(12)nm,b=0.673 01(7)... 标题化合物(C18H17Cl2N3O5)以阿脲水合物和N-3,5-二氯苯基烯胺酮为原料,在醋酸溶剂中,室温下经搅拌合成得到.其结构通过单晶X射线衍射法确定,晶体属单斜晶系,空间群P21/c,相对分子质量Mr=426.25,晶胞参数a=1.018 11(12)nm,b=0.673 01(7)nm,c=2.935 2(2)nm,V=2.007 5(4)nm3,Z=4,晶胞密度Dc=1.410g/cm3,吸收系数μ=0.358mm-1,单胞中电子的数目F(000)=880.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R=0.060 1,ωR=0.141 0.在晶体结构中新形成的吲哚杂环近似于共平面结构. 展开更多
关键词 1H-吲哚-3-甲酰胺 简便 合成 晶体结构
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The effect of easily ionized elements Na and K on the performance of pulsed plasma thruster using water propellant 被引量:1
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作者 ZHU Ping1,2, HOU LiYa1 & ZHANG WeiYi1 1 School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China 2 Instrumentation Science and Dynamic Measurement Laboratory, North University of China, Taiyuan 030051, China 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第10期2878-2882,共5页
In view of the low thrust power ratio caused by the high resistance of pulsed plasma thruster using water propellant,the paper argues that the easily ionized elements Na and K with low ionic potentials are added in th... In view of the low thrust power ratio caused by the high resistance of pulsed plasma thruster using water propellant,the paper argues that the easily ionized elements Na and K with low ionic potentials are added in the water propellant to improve its performance. The measurement of the discharging current and plasma emission spectrographic analysis prove the improvement. The experiments show that the elements Na and K have certain effect on the improvement of the performance of pulsed plasma thruster: In comparison with water propellant,the NaCl and KCl water propellant has a lower total resistance and a higher ratio of thruster power and specific impulse,and the NaCl water propellant has a slightly stronger effect on pulsed plasma thruster than the KCl. The plasma emission spectrographic analysis is in consistent with the experiment of measuring the discharging current: The elements Na and K can intensify the plasma emission spectrographic signal. 展开更多
关键词 PULSED plasma THRUSTER WATER PROPELLANT easily ionized ELEMENTS PERFORMANCE
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Nose-to-brain drug delivery approach:a key to easily accessing the brain for the treatment of Alzheimer's disease 被引量:2
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作者 Amit AlexANDer Shailendra Saraf 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第12期2102-2104,共3页
Alzheimer's disease(AD):AD,a neurodegenerative disorder and a significant cause of dementia throughout the world mostly affects the older adults but sometimes also seen in young age(early state AD)(Agrawal et a... Alzheimer's disease(AD):AD,a neurodegenerative disorder and a significant cause of dementia throughout the world mostly affects the older adults but sometimes also seen in young age(early state AD)(Agrawal et al.,2017). 展开更多
关键词 Nose-to-brain drug delivery approach:a key to easily accessing the brain for the treatment of Alzheimer’s disease AD NGF
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Effect of Sample Matrix on Radial and Axial Profiles of Ion Abundance in Inductively Coupled Plasma Mass Spectrometry
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作者 Clarisse Mariet Francine Carrot Mélanie Moskura 《American Journal of Analytical Chemistry》 2011年第7期739-751,共13页
In inductively coupled plasma mass spectrometry (ICP-MS) analysis, only a few options are available to deal with non-spectroscopic interferences. Considering that diluting the sample is impractical for traces analysis... In inductively coupled plasma mass spectrometry (ICP-MS) analysis, only a few options are available to deal with non-spectroscopic interferences. Considering that diluting the sample is impractical for traces analysis, other alternatives must be employed. Traditionally, the method of standard additions is used to correct the matrix effect but it is a time consuming method. Others methods involves separation techniques. Another way to overcome matrix interferences is to understand the mechanism involved and adjust plasma viewing conditions to reduce or eliminate the effect. In this study, the effect of various concomitant elements in ICP-MS was assessed by measuring the distribution of selected singly charged analyte ions (Al, V, Cr, Mn, Ni, Co, Cu, Zn, As, In, Ba, La, Ce, Pb), doubly charged ions (La, Ce, Ba and Pb) and oxides ions (BaO) in the presence of concomitant elements spanning a mass range from 23 (Na) to 133 (Cs) u.m.a. and different ionization energies. Concomitant elements are alkali metals, alkaline earth metals and Si. Analyte ion suppression was observed while moving the ICP across and away from the sampling interface with or without a single concomitant element. Matrix effect measures were realised, firstly, to highlight the relation between the signal extinction of an analyte and the masse of the concomitant element, and secondly to highlight the relation between the removal of the analyte signal and the first ionization energy of the element of matrix. A dependence upon both the mass of the matrix element and the mass of the analyte was observed. The suppression seems increased with increasing matrix element mass and decreased with increasing analyte mass. The effect of the mass of the matrix element was the more significant of the two factors. If space-charge effects were found to be significant for matrix elements of much lower mass, it seems diffusion also played an active part for heavier matrix elements. Finally, some evidence was found for a shift in ion-atom equilibrium for dications and 展开更多
关键词 MATRIX Effects easily Ionized Elements Inductively Coupled Plasma Mass SPECTROMETRY Spatial PROFILING
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Morphology and Thermal Behavior of Polypropylene/Easily Hydrodegraded Polyester Blend Fibers
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作者 李梅 付中玉 +1 位作者 张大省 王庆瑞 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期50-52,共3页
Ultrafine polypropylene fibers are prepared frompolypropylene/easily hydro - degraded polyester (PP/EHDPET) blend fibers, in which file EHDPET compo-nent is degradable by treating with NaOH - H<sub>2</sub&g... Ultrafine polypropylene fibers are prepared frompolypropylene/easily hydro - degraded polyester (PP/EHDPET) blend fibers, in which file EHDPET compo-nent is degradable by treating with NaOH - H<sub>2</sub>O solu-tion. We investigated the morphology of PP/EHDPETblend fibers before and after stretching and alkalinehydrolysis. Then thermal behavior of the blend has alsobeen studied. 展开更多
关键词 POLYPROPYLENE easily HYDRO - degraded POLYESTER BLEND fiber MORPHOLOGY
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Alkaline Hydrolysis of PP/EHDPET Blend Fibers
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作者 李梅 付中玉 +1 位作者 张大省 王庆瑞 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期44-47,共4页
Polypropylene superfine fibers or cell porous fibers were prepared from the bi-component blend fibers of polypropylene/easlly hydro-degraded polyester(PP/EHDPET)by alkaline hydrolysis process. EHDPET is a kind of copo... Polypropylene superfine fibers or cell porous fibers were prepared from the bi-component blend fibers of polypropylene/easlly hydro-degraded polyester(PP/EHDPET)by alkaline hydrolysis process. EHDPET is a kind of copolyester that can be rapidly hydro-degraded in the hot alkaline solution. This paper discussed the kinetics of alkaline hydrolysis of EHDPET, and the effect of catalyst, bulk ratio and the content of polypropylene grafted maleic anhydride (PP-g-MAH) on the alkaline hydrolysis process. Meanwhile, the morphological change of the outer surface of blend fibers during this process was also investigated by the technology of scanning electron microscope (SEM). 展开更多
关键词 POLYPROPYLENE ( PP) easily HYDRO - degraded POLYESTER (EHDPET) BLEND fibers ALKALINE HYDROLYSIS .
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美学和文艺中的“易”
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作者 张玉能 黄卫星 《城市学刊》 2018年第2期52-57,共6页
《周易》美学思想是中国传统美学思想的源头。在美学和文艺中,"变易"也是艺术辩证法的基本要求,变易应该是美和审美及其艺术的基本规律,简易、平易也是人类美和审美及其艺术发展的一个基本趋势,每一个时代大众文艺、大众审美... 《周易》美学思想是中国传统美学思想的源头。在美学和文艺中,"变易"也是艺术辩证法的基本要求,变易应该是美和审美及其艺术的基本规律,简易、平易也是人类美和审美及其艺术发展的一个基本趋势,每一个时代大众文艺、大众审美与精英艺术、精英审美的相互变易,辩证发展,几乎成为了世界各民族美和审美及其艺术的根本规律。 展开更多
关键词 《周易》 变易 交易 简易 平易 容易
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让高职教育“低进高出”从梦想变成现实
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作者 陈永涛 顾惠明 《常州信息职业技术学院学报》 2007年第1期10-12,共3页
高职教育在党和国家的高度重视下,调整理念,创新办学模式与人才培养模式,以就业为导向、以能力为本位、以服务为宗旨深化教育教学改革,一批高职院校“低进高出”从梦想变成现实。
关键词 高职教育 “低进高出” 教学改革
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学生风采展示板
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《疯狂英语(初中天地)》 2018年第7期59-60,共2页
Dear teacher,I want to recommend Bob to be our new monitor.It is clear that he has a lot of strong qualities for this position.First of all,he is such a helpful person that he is ready to give a helping hand any time.... Dear teacher,I want to recommend Bob to be our new monitor.It is clear that he has a lot of strong qualities for this position.First of all,he is such a helpful person that he is ready to give a helping hand any time.If we have any trouble,he will listen to us carefully and then offer us useful advice.Besides,we all think him smart.He is able to solve difficult problems easily.It is quite simple for him to achieve a balance between his hobby and his schoolwork.Moreover,he is confident.He believes that he can do almost anything if he tries his best.Also,he does things carefully and never forgets the things he needs to do. 展开更多
关键词 carefully PROBLEMS easily confident
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不同森林植被下土壤微生物量碳和易氧化态碳的比较 被引量:139
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作者 朱志建 姜培坤 徐秋芳 《林业科学研究》 CSCD 北大核心 2006年第4期523-526,共4页
Soils under broad-leaved,masson pine,Chinese fir and bamboo forests in the area of Huzhou,Zhejiang were collected and analyzed in January 2000.Soil total organic carbon(TOC) under broad-leaved and bamboo forests were ... Soils under broad-leaved,masson pine,Chinese fir and bamboo forests in the area of Huzhou,Zhejiang were collected and analyzed in January 2000.Soil total organic carbon(TOC) under broad-leaved and bamboo forests were considerately higher than(P<0.01)those under masson pine and Chinese fir.There was no significant differences in microbial biomass carbon(MBC) in soils among various types of vegetation,however,the bamboo stands constituted a lower(P<0.05) proportion of MBC compared with broad-leaved forest,masson pine and Chinese fir were similar in MBC to TOC,indicating that intensive management in bamboo stand reduced the proportion of soil MBC in TOC.MBC in soils under broad-leaved forest,masson pine forest and Chinese fir forest had strong positive relationships with the corresponding TOCs,the correlation coefficients were respective 0.744 4,0.648 4 and 0.552 1.It was found that soil easily oxidizable carbon(EOC) in bamboo forest was much higher than those in the other 3 forests.The higher percentages of EOC were detected from soils under bamboo forest(52.40%) and Chinese fir forest(50.50%) compared with broad-leaved forest(48.90%) and masson pine forest(45.74%).Soil EOC for all 4 forests were closely correlated(P<0.01)with the correspondent TOCs. 展开更多
关键词 森林土壤 总有机碳 微生物量碳 易氧化态碳
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川西沿海拔梯度典型植被类型土壤活性有机碳分布 被引量:68
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作者 向成华 栾军伟 +1 位作者 骆宗诗 宫渊波 《生态学报》 CAS CSCD 北大核心 2010年第4期1025-1034,共10页
研究土壤活性有机碳含量及分配比例是揭示土壤碳库周转及调控机理的重要途径,通过利用高锰酸钾氧化法获得易氧化有机碳、湿筛法获得颗粒有机碳和密度分离法获得轻组有机碳3项指标探讨沿海拔梯度不同植被类型间(山地常绿阔叶林、常绿落... 研究土壤活性有机碳含量及分配比例是揭示土壤碳库周转及调控机理的重要途径,通过利用高锰酸钾氧化法获得易氧化有机碳、湿筛法获得颗粒有机碳和密度分离法获得轻组有机碳3项指标探讨沿海拔梯度不同植被类型间(山地常绿阔叶林、常绿落叶阔叶混交林、落叶阔叶林、针阔混交林、暗针叶林)土壤活性有机碳含量差异及调控因子,结果表明:随土层加深,土壤颗粒和轻组有机碳含量及分配比例均降低,土壤易氧化有机碳含量降低而分配比例保持较稳定水平。高海拔植被类型具有较高的土壤活性有机碳含量和分配比例。不同活性有机碳含量之间均呈显著线性相关(P<0.05)表明活性有机碳起源的类似。活性有机碳与土壤粘粒+粉粒含量百分比呈显著负相关(P<0.05)表明活性有机碳趋向分布于土壤大团聚体当中。年均温与不同植被类型间表层土壤活性有机碳含量和分配比例成负相关趋势,但可能由于取样点较少的缘故而在统计上不显著。年均温与土壤非保护性有机碳向保护性有机碳的转化速率常数(K)接近于显著负相关(P=0.062)。 展开更多
关键词 活性有机碳 易氧化有机碳 轻组有机碳 颗粒有机碳
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复杂铜铅锌多金属硫化矿选矿试验研究 被引量:62
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作者 王云 张丽军 《有色金属(选矿部分)》 CAS 2007年第6期1-6,共6页
针对某地含银铜铅锌多金属硫化矿易浮难分、嵌布粒度极不均匀的特点,采用优先浮选工艺流程,以硫化钠消除次生铜离子的影响,组合药剂浮选铜铅锌,铜铅粗精矿再磨显著提高铜铅锌分选效果,获得了较佳的分选指标,铜精矿含铜23.44%、回收率88.... 针对某地含银铜铅锌多金属硫化矿易浮难分、嵌布粒度极不均匀的特点,采用优先浮选工艺流程,以硫化钠消除次生铜离子的影响,组合药剂浮选铜铅锌,铜铅粗精矿再磨显著提高铜铅锌分选效果,获得了较佳的分选指标,铜精矿含铜23.44%、回收率88.83%,铅精矿含铅54.43%、回收率84.28%,锌精矿含锌55.72%、回收率83.72%。 展开更多
关键词 多金属硫化矿 易浮难分 组合药剂 单体解离度
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2005年夏季环渤海16条主要入海河流的污染状况 被引量:45
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作者 张龙军 夏斌 +1 位作者 桂祖胜 江春波 《环境科学》 EI CAS CSCD 北大核心 2007年第11期2409-2415,共7页
2005-07-01~2005-07-05对环渤海的黄河等16条主要河流的入海污染同步调查显示,13条河流断面的水质属于Ⅳ类以上,其中子牙新河等8条河流水质属于劣Ⅴ类,通过污染分担率分析,环渤海河流的首要污染物为石油类(11条河流),其次为营养盐,... 2005-07-01~2005-07-05对环渤海的黄河等16条主要河流的入海污染同步调查显示,13条河流断面的水质属于Ⅳ类以上,其中子牙新河等8条河流水质属于劣Ⅴ类,通过污染分担率分析,环渤海河流的首要污染物为石油类(11条河流),其次为营养盐,高锰酸盐指数仅位居第3.采用综合营养状态指数法评价,大辽河、黄河等7条河流处于富营养状态,而小清河、蓟运河等7条河流处于重度富营养状态,可见环渤海河流的富营养化现象非常严重.有机污染物的调查显示,16条河流断面采样点TOC的平均值为16.41 mg/L,高锰酸盐指数的平均值为6.04 mg/L,其中易降解有机物所占比例平均为15.61%,表明虽然环渤海16条河流中的化学需氧有机物质的污染严重,但总有机物的入海通量更大,这一点必须引起足够的重视. 展开更多
关键词 环渤海河流 污染状况 富营养化 有机污染物 易降解有机物
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同沉积期火山作用对鄂尔多斯盆地上古生界砂岩储层形成的意义 被引量:39
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作者 包洪平 杨奕华 +1 位作者 王晓方 南珺祥 《古地理学报》 CAS CSCD 2007年第4期397-406,共10页
鄂尔多斯盆地上古生界主要为一套陆源碎屑沉积体系,其中广泛发育河流一三角洲相砂岩储集体,是该区上古生界天然气聚集成藏的主要场所。但由于陆源杂基的充填以及成岩压实作用、胶结作用的改造,大部分砂层储集性能都较差而无工业性储集... 鄂尔多斯盆地上古生界主要为一套陆源碎屑沉积体系,其中广泛发育河流一三角洲相砂岩储集体,是该区上古生界天然气聚集成藏的主要场所。但由于陆源杂基的充填以及成岩压实作用、胶结作用的改造,大部分砂层储集性能都较差而无工业性储集意义。本文通过对鄂尔多斯盆地上古生界砂岩储层孔隙成因的分析,提出在局部层段集中分布的孔隙性砂岩,其孔隙主要为次生溶蚀成因。进一步的研究表明,由同沉积期火山作用形成的、分布于砂岩层中的火山碎屑组分的成岩溶蚀是次生溶孔形成的主要原因。因此,同沉积期火山作用控制了该区上古生界主要砂岩储层的发育和分布。中基性火山作用由于能提供较多的"易溶组分",从而控制了次生溶孔发育的较高渗透性砂岩储层的分布;而影响更为广泛的酸性火山作用则主要形成以蚀变高岭石晶间孔为主的低渗透性储层。 展开更多
关键词 鄂尔多斯盆地 同沉积期火山作用 易溶组分 次生溶孔 孔隙成因 砂岩储层
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农村地区雷电灾害活动规律和防护技术研究 被引量:37
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作者 汪顺勤 《安徽农业科学》 CAS 北大核心 2009年第15期7083-7084,7103,共3页
通过对农村雷电灾害的调查研究和防护实践,分析总结了农村雷电灾害活动规律,并根据农村的现实条件,有针对性地提出了农村雷电灾害全方位防护技术方案。
关键词 农村防雷 易雷击区 防护技术
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偏、粘和易型非1B/1R小麦雄性不育系研究初报 被引量:16
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作者 张改生 赵惠燕 +1 位作者 吴兆苏 俞世蓉 《西北农业学报》 CSCD 1994年第4期7-12,共6页
以偏、粘和易型1B/1R稳定全不育系ms(Ae.ventricosa)—77(2)、ms(Ae.kotschyi)—77(2)和ms(Ae.variabilis)—77(2)为不育质核背景,一批优良小麦品种(系)及部... 以偏、粘和易型1B/1R稳定全不育系ms(Ae.ventricosa)—77(2)、ms(Ae.kotschyi)—77(2)和ms(Ae.variabilis)—77(2)为不育质核背景,一批优良小麦品种(系)及部分亲本材料为父本,诱导单倍体性和易恢复性为重要选择指标,采用测交、置换回交和转育等方法,并结合细胞学镜检,首次成功地将带有rfvl基因的非1B/1R普通小麦栽培品种与偏凸、粘果和易变不育胞质结合,培育出稳定的偏、粘和易型非1B/1R全不育系ms(ven)—90—110、ms(kots)—90—110和ms(var)—90—110。测交和育性分析结果表明:(1)其不育性主要由一对主效隐性基因控制。(2)从不育系自身完全克服了1B/1R不育系产生单倍体的缺点;同时大大提高了其不育性的易恢复性,其不育系与一般只要含有主效恢复基因(Rfvl)的小麦品种(系)测配,凡杂种恢复度大都在85%~90%以上。(3)其育性恢复基因分析广泛,一般生产中的非1B/1R优良品种(系)都带有它们的主效恢复基因,可以自然恢复系形式恢复其育性。为小麦杂优利用中更广泛采用偏凸、粘果和易变不育胞质来配制杂种,促使和加快杂种小麦选? 展开更多
关键词 小麦 易恢复性 三系配套
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