期刊文献+
共找到10篇文章
< 1 >
每页显示 20 50 100
高岭石有机插层复合材料的研究及其应用 被引量:8
1
作者 顾涛 邹正光 《硅酸盐通报》 CAS CSCD 北大核心 2005年第4期70-74,共5页
综述了高岭石/有机物插层复合物发展,分析了高岭石插层复合物插层机理,粘土矿物及高岭土有机物插层应用及插层复合物合成Sialon陶瓷的制备,并对其发展前景进行了展望。
关键词 高岭石 有机物 复合物 复合材料 有机物 应用 SIALON陶瓷 复合物 机理 粘土矿物
下载PDF
Diversity of filamentous fungi in organic layers of two forests in Zijin Mountain 被引量:3
2
作者 宋福强 田兴军 +4 位作者 李重琦 杨昌林 陈斌 郝杰杰 朱静 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期273-279,共7页
A study was conducted to evaluate the cultivable filamentous fungal diversity in organic layers (L, F, and H layers) and A1 layer of two main forest types, Pinus massoniana and Liguidambar formasana mixed forest and Q... A study was conducted to evaluate the cultivable filamentous fungal diversity in organic layers (L, F, and H layers) and A1 layer of two main forest types, Pinus massoniana and Liguidambar formasana mixed forest and Quercus variabilis forest, in Zijin Mountain(325?N, 11848?E), Nanjing, China. A total of 67 taxa comprising 56 Deuteromycetes, 3 Zygomycetes, 5 Asco-mycetes and 3 unidentified fungi were recognized from samples from the forest floor of the two forest types. The most abundant group was Deuteromycetes. The dominant genera in both forests were Alternaria sp., Aspergillus sp., Cladosporium sp., Mucor sp., Penicillium sp., Rhizopus sp., Gliocladium sp. and Trichoderma spp. The fungal diversity was higher in the mixed forest than that in Q. variabilis forest. For both forest types, the maximum fungal diversity was found in layer F and there existed significantly different in fungal diversity between layer F and layer L. In the mixed forest, richness of fungi isolated from needle litter (P. massoniana) was lower than that from leaf litter (L. formasana). The richness of fungi from needle litter increased with the in-crease of forest floor depth, but for leaf litter, the fungal diversity decreased with the depth of forest floor. The co-species of fungi from the two forest types, as well as from two kinds of litters in mixed forest, increased with the depth of the forest floor. The succession of fungi along with the process of decomposition was discussed here. The results also showed that litter quality was a critical factor affecting fungal diversity. 展开更多
关键词 Zijin Mountain Forest type Filamentous fungi DIVERSITY LITTER Quercus variabilis forest Pinus massoniana and Liguidambar formasana mixed fores
下载PDF
Removal and transformation of organic matter during soil-aquifer treatment 被引量:1
3
作者 ZHAO Qing-liang XUE Shuang +1 位作者 YOU Shi-jie WANG Li-na 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第5期712-718,共7页
This study investigated the removal and transformation of organic matter through laboratory-scale soil-aquifer treatment (SAT) soil columns over a 110-day period. Reductions in total organic carbon (TOC), dissolved or... This study investigated the removal and transformation of organic matter through laboratory-scale soil-aquifer treatment (SAT) soil columns over a 110-day period. Reductions in total organic carbon (TOC), dissolved organic carbon (DOC), biodegradable dissolved organic carbon (BDOC), nonbiodegradable dissolved organic carbon (NBDOC) and absorbance of ul-traviolet light at 254 nm (UV-254) averaged 71.46%, 68.05%, 99.31%, 33.27% and 38.96% across the soil columns, respectively. DOC/TOC ratios increased slightly with depth while BDOC/DOC ratios showed a converse trend. DOC exiting the soil-column system contained only a very small biodegradable fraction. SAT decreased the concentration of DOC present in feed water but increased its aromaticity, as indicated by specific ultraviolet light absorbance (SUVA), which increased by 50%~115% across the soil columns, indicating preferential removal of non-aromatic DOC during SAT. Overall, laboratory-scale SAT reduced triha-lomethane formation potential (THMFP), although specific THMFP increased. THMFP reduction was dominated by removal in chloroform. All samples exhibited a common general relationship with respect to weight: chloroform>dichlorobromomethane >dibromochloromethane>bromoform. 展开更多
关键词 Soil-aquifer treatment (SAT) Organic matter Dissolved organic matter Trihalomethane formation potential Bio-degradable dissolved organic carbon (BDOC) Specific trihalomethane formation potential
下载PDF
Determination of Organochlorine Compounds in Sediments from the Upper Middle Sao Francisco River (Bahia, Brazil)
4
作者 Alexsandro Fiscina de Santana Eva Vidal Vatzquez +1 位作者 Jorge Paz-Ferreiro Magda Beretta 《Journal of Earth Science and Engineering》 2012年第7期401-411,共11页
The objective of this study was to determine the contamination of OCPs (organochlorine pesticides) in sediments from the upper middle of Sao Francisco River (Bahia, Brazil) in order to evaluate their potential pol... The objective of this study was to determine the contamination of OCPs (organochlorine pesticides) in sediments from the upper middle of Sao Francisco River (Bahia, Brazil) in order to evaluate their potential pollution risks. Samples of surface sediments were collected using a Petersen dredge at 21 stations located between Sobradinho and Cura^i. The organochlorine compounds analyzed were: p,p'-DDT, p,p'-DDD, p,p'-DDE, dicofol, methoxychlor, HCHs, aldrin, endrin, endrin aldehyde, endrin ketone, dieldrin, heptachlor, heptachlor epoxide, endosulfan (ct, fl and sulfate) and chlordane (ct and ,/). Extractions were carried out using the MAE (microwave-assisted extraction) method and organochlorine pesticides determination was achieved by GC/MS (gas chromatography-mass spectrometry). Organochlorine concentrations ranged between 1.51-820.00 ng.gx, indicating very low to high levels. The most frequent OCPs were endrin aldehyde, -HCH, HCH, HCH, heptachlor and heptachlor epoxide. 展开更多
关键词 SEDIMENTS organochlorine pesticides SAo Francisco River Brazil.
下载PDF
Origins of Terrestrial Organic Matter in Surface Sediments of the East China Sea Shelf 被引量:5
5
作者 ZHANG Hailong XING Lei ZHAO Meixun 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第5期793-802,共10页
Terrestrial organic matter(TOM) is an important component of marine sedimentary OM, and revealing the origins and transport mechanisms of TOM to the East China Sea(ECS) is important for understanding regional carbon c... Terrestrial organic matter(TOM) is an important component of marine sedimentary OM, and revealing the origins and transport mechanisms of TOM to the East China Sea(ECS) is important for understanding regional carbon cycle. A novel approach combining molecular proxies and compound-specific carbon isotopes is used to quantitatively constrain the origins and transport mechanisms of TOM in surface sediments from the ECS shelf. The content of terrestrial biomarkers of(C_(27)+C_(29)+C_(31)) n-alkanes(52 to 580 ng g^(-1)) revealed a seaward decreasing trend, the δ^(13)CTOC values(-20.6‰ to-22.7‰) were more negative near the coast, and the TMBR(terrestrial and marine biomarker ratio) values(0.06 to 0.40) also revealed a seaward decreasing trend. These proxies all indicated more TOM(up to 48%) deposition in the coastal areas. The Alkane Index, the ratio of C_(29)/(C_(29)+C_(31)) n-alkanes indicated a higher proportion of grass vegetation in the coastal area; While the δ13C values of C_(29) n-alkane(-_(29).3‰ to-33.8‰) indicated that terrestrial plant in the sediments of the ECS shelf were mainly derived from C_3 plants. Cluster analysis afforded detailed estimates of different-sourced TOM contributions and transport mechanisms. TOM in the Zhejiang-Fujian coastal area was mostly delivered by the Changjiang River, and characterized by higher %TOM(up to 48%), higher %C_3 plant OM(68%-85%) and higher grass plant OM(56%-61%); TOM in the mid-shelf area was mostly transported by aerosols, and characterized by low %TOM(less than 17%), slightly lower C_3 plant OM(56%-72%) and lower grass plant OM(49%-55%). 展开更多
关键词 alkanes coastal terrestrial shelf sedimentary mostly aerosols vegetation quantitatively decreasing
下载PDF
Residues of organochlorine pesticides in intertidal flat surface sediments from coastal zone of Jiangsu Province, China
6
作者 韩秀梅 郑容 +2 位作者 赵家乐 马超 高效江 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1157-1162,共6页
Sixteen surface sediment samples were collected and analysed to evaluate the residues of organochlorine pesticides (OCPs) from intertidal fiat in Jiangsu Province. Overall, 22 OCPs were detected with total concentra... Sixteen surface sediment samples were collected and analysed to evaluate the residues of organochlorine pesticides (OCPs) from intertidal fiat in Jiangsu Province. Overall, 22 OCPs were detected with total concentrations of OCPs ranging widely from 0.96 to 12.14 ng/g (dry wt). Total hexachlorocyclohexane (HCH) and total dichlorodiphenyltrichloroethane (DDT) levels varied from 〈0.01 to 0.67 ng/g and from 0.23 to 4.85 ng/g, respectively. DDTs were the predominant compounds. The dominance of β-HCH indicated a history of HCH pollution. According to the ratios of (p,p'-DDD+p,p'-DDE)/p,p'DDT and o,p'-DDT/p,p'- DDT, new input of DDTs did not occur in most sites, and the main sources were historical usage of technical DDTs. OCPs such as dieldrin, endrin, p,p'-DDD, and p,p'-DDT exceeded the effects range low, showing adverse biological effects that would occasionally occur at some sites of the study area. 展开更多
关键词 organochlorine pesticides (OCPs) intertidal fiat sediment coastal zone Jiangsu Province
下载PDF
Organic-magnesium complex conversion coating on AZ91D magnesium alloy
7
作者 陈晓明 李光玉 连建设 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期643-647,共5页
An organic-magnesium complex conversion(OMCC)coating on AZ91D magnesium alloy was obtained by treating in a solution containing organic compounds.SEM,FESEM and XPS were used to examine the surface morphology,thickness... An organic-magnesium complex conversion(OMCC)coating on AZ91D magnesium alloy was obtained by treating in a solution containing organic compounds.SEM,FESEM and XPS were used to examine the surface morphology,thickness and structure of the conversion coatings.The results show that the continuous and uniform conversion coating is deposited on AZ91D alloy and the main component of the coatings is organic compound containing benzene ring,which forms a chemical bond with magnesium.The polarization measurement and salt spray test show that the corrosion resistance of the conversion coating is much higher than that of traditional chromate conversion coating. 展开更多
关键词 chromium-free conversion coating organic compound CORROSION XPS AZ91D magnesium alloy
下载PDF
A Hierarchic Method for Studying the Distribution of Phenanthrene in Eisenia fetida 被引量:4
8
作者 SHI Zhi-Ming XU Li HU Feng 《Pedosphere》 SCIE CAS CSCD 2014年第6期743-752,共10页
The distribution of heavy metals in earthworms has been widely studied, highlighting the importance of the fate of these metals.However, little information is available on the distribution of hydrophobic organic conta... The distribution of heavy metals in earthworms has been widely studied, highlighting the importance of the fate of these metals.However, little information is available on the distribution of hydrophobic organic contaminants(HOCs) within earthworms. The aim of this study was to propose a hierarchic method to study the distribution of phenanthrene(PHE), a typical HOC, in Eisenia fetida at several levels: sub-organism(pre-clitellum, clitellum and post-clitellum), tissue(body wall, gut and body fluid) and subcellular(intracellular and extracellular fractions). Earthworms were incubated in the soils amended with low(LC, 10 mg kg-1) and high concentrations(HC, 50 mg kg-1) of PHE and sampled at different time intervals. At the sub-organism level, the distribution of PHE was homogeneous among the sub-organism fractions in the LC treatment but heterogeneous in the HC treatment and gradually reached the following form of post-clitellum ≈ clitellum > pre-clitellum. The uptake and elimination kinetics of PHE in the sub-organism were well described by a one-compartment model. At the tissue level, the concentration of PHE followed the order of gut > body fluid >body wall; while at the subcellular level, the concentration of PHE in the extracellular fraction was 1.23 to 4.68 times higher than that in the intracellular fraction. Therefore, the simple circulatory system of earthworms may account for the PHE distribution at the sub-organism level. Partition pathways(passive diffusion) of PHE between the body wall, body fluid and gut as well as the processes of PHE entrance into the inner cellular compartment via passive diffusion were experimentally supported. 展开更多
关键词 EARTHWORM passive diffusion subcellular level sub-organism level tissue level
原文传递
The significance and variation characteristics of interlay water in smectite of hydrocarbon source rocks 被引量:6
9
作者 CAI JinGong LU LongFei +2 位作者 BAO YuJin FAN Fu XU JinLi 《Science China Earth Sciences》 SCIE EI CAS 2012年第3期397-404,共8页
To investigate variation characteristics of interlayer water bound up with organic matter in smectite, organo-clay complexes extracted from grinded source rock samples were determined using thermo-XRD, DTA and PY-GC. ... To investigate variation characteristics of interlayer water bound up with organic matter in smectite, organo-clay complexes extracted from grinded source rock samples were determined using thermo-XRD, DTA and PY-GC. The dool diffraction peak of organo-clay complexes is postponed from 250 to 550℃ before reaching 1.00 nm and accompanied by exothermal peaks on DTA and organic matter with abundant C20-C30carbon detected by PY-GC, which is different from single smectite and indicates the existence of organic matter in the interlayer of smectite. Water desorption characteristics of organo-clay complexes are in consistent with smectite at 100 and 600℃, but different from smectite at 550℃ with an additional dehydration peak and a remaining d001 diffraction peak, suggesting the vcater removed at 550℃ is interlayer adsorption water rather than constituent water of clay minerals. Comparing the dehydration order and water loss, we conclude that part of interlayer water of smectite may act as the "bridge" that binds organic matter and smectite, which results in water-expelled lag beyond 250℃ and may provide a good medium for hydrocarbon migration and oil pool formation. 展开更多
关键词 source rocks organo-clay complexes interlayer water organic matter
原文传递
Theoretical limiting concentration for mineralization of trichloromethane and dichloromethane in aqueous solutions by AOPs
10
作者 JI YuanHui HUANG WenJuan LU XiaoHua YANG ZhuHong FENG Xin 《Science China Chemistry》 SCIE EI CAS 2011年第3期559-564,共6页
It is widely stated that most organic contaminants could be completely mineralized by Advanced Oxidation Processes(AOPs). This statement means that the concentration of the organic contaminant at equilibrium(limiting ... It is widely stated that most organic contaminants could be completely mineralized by Advanced Oxidation Processes(AOPs). This statement means that the concentration of the organic contaminant at equilibrium(limiting concentration,LC)is low enough to be neglected.However,for environmental safety,especially drinking water safety,this statement needs to be verified from chemical engineering thermodynamic analysis.In this paper,trichloromethane(CHCl3)and dichloromethane(CH2Cl2) are selected as the model systems,and the equilibrium concentration(theoretical limiting concentration,TLC)for the mineralization of chlorinated methanes in aqueous solutions at the different initial concentrations of chlorinated methanes,pH values and·OH concentrations by AOPs are investigated by thermodynamic analysis.The results in this paper show that the TLC for the mineralization of CHCl3 and CH2Cl2 with·OH increases with increasing initial concentrations of CHCl3 and CH2Cl2,decreases with increasing concentration of·OH,and the TLC for the mineralization of CHCl3 decreases with increasing pH values except that the pH value changes from 3.0 to 3.5.For the mineralization of CH2Cl2 with·OH,at the concentrations of·OH obtained from the literature,there is no obvious change of the TLC with pH values,while as the concentrations of·OH increase by 10 and 100 times,the TLC decreases with the increasing pH values from 2.0 to 3.0 and from 3.5 to 4.5,and increases with the increasing pH values from 3.0 to 3.5 and from 4.5 to 5.0.The investigations in this paper imply that high concentration of·OH,a bit higher pH values(4.0–5.0)in acid environment and low initial concentrations of the organic contaminants are beneficial for the complete mineralization of chlorinated methanes by AOPs. 展开更多
关键词 thermodynamic analysis chemical equilibrium theoretical limiting concentration organic contaminant mineralization degree advanced oxidation processes chlorinated methane
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部