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Effect of Temperature, pH and Salt on Fluorescent Quality of Water Extractable Organic Matter in Black Soil 被引量:9
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作者 LI Ming-tang ZHAO Lan-po ZHANG Jin-jing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第7期1251-1257,共7页
Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction tempera... Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction temperature, pH value, and salt on the water extractable organic matter (WEOM) was determined by means of the UV absorbance, fluorescence excitation-emission matrix, and derived fluorescence indexes. In general, the carbon content and aromaticity of WEOM increased with the increasing of extraction temperature, with the exception that there was no significant difference in the amount at 0 and 20℃. More fluorophores, especially microbially-derived organic matter were extracted at high temperature. The pH values of extractant, including 5, 7, and 10, showed no effect on the carbon amount of WEOM, whereas the aromaticity and microbially-derived component gradually increased with the increasing of pH values. The fluorescence intensity of humic acid-like fluorophore was stronger in neutral and alkali condition than that in acidic condition. The addition of 10 mmol L-1 CaCl2 significantly decreased the carbon amount of recovered WEOM. Moreover, it significantly decreased the aromaticity of WEOM and the quantity of fulvic acid-like and humic acid-like fluorophores, whereas increased the percentage of tyrosine-like and tryptophan-like fluorophores in the total fluorophores and the amount of microbially-derived organic matter. Generally, 10 mmol L-1 KCl showed the same influence trend, but with low influence degree. 展开更多
关键词 black soil water extractable organic matter soil profile fluorescence spectroscopy
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Organic matter extracted from activated sludge with ammonium hydroxide and its characterization 被引量:1
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作者 Liangliang Wei Kun Wang +3 位作者 Qingliang Zhao Junqiu Jiang Chunmei Xie Wei Qiu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期641-647,共7页
In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated i... In order to characterize the organic properties of waste activated sludge in a wastewater treatment plant,organic matter within sludge was extracted with NH 3 ·H 2 O preferentially,and subsequently fractionated into five fractions using XAD-8/XAD-4 resins.Up to a 63.8%-71.1% of organic matter within the sludge could be efficiently extracted by NH 3 ·H 2 O.Fractionation results showed that hydrophobic acid and hydrophilic fraction were two main components among the sludge organic matter (accounting for 32.2% and 48.0% of the bulk organic matter,respectively),whereas transphilic acid,hydrophobic neutral and transphilic neutral were quite low (accounting for 9.2%,5.8% and 4.8%,respectively).Despite that the extractant of NH 3 ·H 2 O showed a relatively higher extraction efficiency of the aromatic components,the relatively low aromaticity of the organic fractions implied that those non-aromatic components could also be effectively extracted,especially for neutral and hydrophilic fractions.In addition,acidic fractions contained more aromatic humic-like components,whereas the neutral fractions had a greater content of aromatic proteins and soluble microbial byproduct-like components.Extraction of sludge organics with NH3·H2O and subsequential fractionation using XAD resins could be a novel method for further characterization of sludge organics. 展开更多
关键词 sludge organic matter extraction FRACTIONATION CHARACTERIZATION
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Effect of Alkaline-Stabilised Sewage Sludge on Extractable Organic Carbon and Copper in Soils 被引量:4
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作者 LUOYONGMING P.CHRISTIE 《Pedosphere》 SCIE CAS CSCD 2002年第2期97-102,共6页
An incubation experiment was conducted to evaluate the potential for water contamination with sludge-derived organic substances and copper following land application of alkaline-stabilised sewage sludge. Twocontrastin... An incubation experiment was conducted to evaluate the potential for water contamination with sludge-derived organic substances and copper following land application of alkaline-stabilised sewage sludge. Twocontrasting sludge-amended soils were studied. Both soils were previously treated with urban and ruralalkaline biosolids separately at sludge application rates of 0, 30 and 120 t ha-1 fresh product. The air-driedsoil/sludge mixtures were wetted with distilled water, maintained at 40 % of water-holding capacity andequilibrated for three weeks at 4 ℃ before extraction. Subsamples were extracted with either distilled wateror 0.5 mol L-1 K2SO4 solution. The concentrations of organic C in the aqueous and chemical extractswere determined directly with a total organic carbon (TOC) analyser. The concentrations of Cu in the twoextracts were also determined by atomic absorption spectrophotometry The relationship between the twoextractable organic C fractions was examined, together with 展开更多
关键词 土壤 泥土 污水 解压缩 滤取 金属
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Supercritical Carbon Dioxide Extraction of Organic Matter from Petroleum Source Rocksand Its Implications
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作者 沈忠民 周光甲 +2 位作者 李辉祥 苗得玉 李佩珍 《Chinese Journal Of Geochemistry》 EI CAS 1996年第4期324-330,共7页
Organic matter was experimentally extracted by supercritical fiuids (CO2 +1% isopropanol) from petroleum source rocks of different thermo-maturities at different buried depths in the same stratigraphic unit in the D... Organic matter was experimentally extracted by supercritical fiuids (CO2 +1% isopropanol) from petroleum source rocks of different thermo-maturities at different buried depths in the same stratigraphic unit in the Dongying Basin. The results show that supercritical fluid extraction (SFE) is more effective than Soxhlet extraction (SE), with higher amounts and greater varieties of hydrocarbons and soluble organic matter becoming extractive. The supercritical CO2 extraction is therefore considered more valuable in evaluation of petroleum source rocks and oil resources, particularly those of immature types. 展开更多
关键词 石油 有机物 岩石 二氧化碳 未成熟油 超临界流体
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不同分离方法分离烃源岩可溶有机质的对比实验
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作者 田鑫 程斌 +2 位作者 马大钧 邓德国 孙杰 《分析仪器》 CAS 2024年第3期56-62,共7页
对加速溶剂萃取与索式提取两种烃源岩可溶有机质分离方法的分离总量、分离效率、可溶有机质的化学与分子组成进行了对比。结果表明:加速溶剂萃取分离出的可溶有机质总量略低于索式提取,但分离效率远高于索式提取;加速溶剂萃取所得的可... 对加速溶剂萃取与索式提取两种烃源岩可溶有机质分离方法的分离总量、分离效率、可溶有机质的化学与分子组成进行了对比。结果表明:加速溶剂萃取分离出的可溶有机质总量略低于索式提取,但分离效率远高于索式提取;加速溶剂萃取所得的可溶有机质中饱和烃与芳香烃的相对百分含量高于索式提取,非烃与沥青质的相对百分含量低于索式提取;两种分离方法所得的可溶有机质中高碳数饱和烃与芳香烃化合物的分布形态、地球化学比值参数和绝对含量均具有很好的可比性,相反,二环倍半萜系列化合物显示较大差异,加速溶剂萃取所得可溶有机质的低碳数、低沸点的二环倍半萜化合物的相对百分含量高于索式提取。 展开更多
关键词 加速溶剂萃取 索式提取 可溶有机质分离 生物标志化合物
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PM_(2.5)有机提取物经由铁死亡诱导人支气管上皮细胞损伤的研究
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作者 王盟盟 龙玥含 +5 位作者 陈圆圆 顾雯 王超 石莹 唐宋 段链 《环境卫生学杂志》 2024年第4期303-311,361,共10页
目的探讨细颗粒物(PM_(2.5))有机提取物能否诱导人支气管上皮细胞铁死亡。方法通过索氏提取法提取PM_(2.5)中有机物作为受试物,使用BEAS-2B细胞,以0.1%DMSO溶液作为溶剂对照,染毒于不同剂量(2.5、5、10和20μg/mL)的PM_(2.5)有机提取物... 目的探讨细颗粒物(PM_(2.5))有机提取物能否诱导人支气管上皮细胞铁死亡。方法通过索氏提取法提取PM_(2.5)中有机物作为受试物,使用BEAS-2B细胞,以0.1%DMSO溶液作为溶剂对照,染毒于不同剂量(2.5、5、10和20μg/mL)的PM_(2.5)有机提取物构建细胞染毒模型;使用铁死亡抑制剂(Ferrostatin-1,Fer-1)构建铁死亡干预模型。通过吸光度法检测PM_(2.5)有机提取物染毒后BEAS-2B细胞存活率、丙二醛(malondialdehyde,MDA)和谷胱甘肽(glutathione,GSH)浓度;通过荧光法检测细胞内Fe2+含量、活性氧(reactive oxygen species,ROS)含量和脂质过氧化物(lipid peroxidation,LPO)含量;通过qRT-PCR方法检测铁死亡相关基因(如GPX4、SLC7A11、ACSL4、FTL和TFRC等)表达。结果与对照组相比,PM_(2.5)有机提取物染毒24 h后,当染毒剂量为10μg/mL时,细胞内Fe2+含量、ROS含量、LPO含量和MDA浓度均出现显著上升;而GSH浓度出现显著下降;qRT-PCR结果显示,细胞暴露于20μg/mL PM_(2.5)有机提取物时,细胞内铁死亡相关基因GPX4显著下调,SLC7A11、ACSL4、FTL和TFRC出现显著性上调。干预实验中,使用铁死亡特异性抑制剂Fer-1干预后上述变化得到明显改善。结论PM_(2.5)有机提取物可能通过诱导细胞铁死亡导致呼吸系统细胞损伤,进而对肺组织产生潜在健康影响。 展开更多
关键词 细颗粒物(PM_(2.5)) 有机提取物 铁死亡 人支气管上皮细胞 肺损伤
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工业铝酸钠溶液中腐殖酸的检测分析及降解规律研究
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作者 王明理 皮溅清 +2 位作者 赵志强 范尚 韦金钏 《中国有色冶金》 CAS 北大核心 2024年第3期72-80,共9页
铝酸钠溶液中的有机物对氧化铝生产危害较大,目前铝酸钠溶液中腐殖酸浓度测定操作流程繁琐、测定结果准确度低,本文创新性提出了以“萃取-沉淀法”测定的腐殖酸浓度为基础,采用“吸光光度法”快速测定腐殖酸浓度的方法,并探讨进入工业... 铝酸钠溶液中的有机物对氧化铝生产危害较大,目前铝酸钠溶液中腐殖酸浓度测定操作流程繁琐、测定结果准确度低,本文创新性提出了以“萃取-沉淀法”测定的腐殖酸浓度为基础,采用“吸光光度法”快速测定腐殖酸浓度的方法,并探讨进入工业铝酸钠溶液中的腐殖酸在高温循环过程中的降解规律,得到以下主要结论。萃取-沉淀法测定的原理是在反萃溶液中加入钡盐溶液沉淀腐殖酸,然后焙烧沉淀物,通过焙烧产物的质量推算腐殖酸浓度,试验用工业铝酸钠溶液中的腐殖酸浓度为1.80 g/L;吸光光度法测定的原理是先通过试验测定吸光度曲线方程Y=1.6298X-0.1628,再测定待测溶液吸光度,吸光度测量值应在0.2~2.0之间,代入方程即可计算出待测溶液中的腐殖酸浓度。温度和时间对腐殖酸的去除影响较大,温度越高,保温时间越长腐殖酸的去除率越高,280℃保温1 h后,腐殖酸去除率为68.30%;温度和时间对铝酸钠溶液中的总有机碳,以及丙二酸根、甲酸根、乙酸根、丁二酸根和草酸等小分子酸的质量浓度影响不大,但是草酸根质量浓度在长时间保温后则有较大幅度的增加,工业生产中需关注草酸钠质量浓度的变化。 展开更多
关键词 铝冶炼 铝酸钠溶液 有机物检测 腐殖酸浓度 萃取-沉淀法 吸光光度法 腐殖酸去除率 降解规律
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Evaluating Soil Dissolved Organic Matter Extraction Using Three-Dimensional Excitation-Emission Matrix Fluorescence Spectroscopy 被引量:7
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作者 XIE Wenming ZHANG Shanshan +4 位作者 RUAN Lin YANG Mingyue SHI Weiming ZHANG Hailin LI Weihua 《Pedosphere》 SCIE CAS CSCD 2017年第5期968-973,共6页
Soil dissolved organic matter(DOM) consists of many organic compounds and plays an important role in contaminant transport in the ecosystem. However, the effects of different extraction conditions on contents of diffe... Soil dissolved organic matter(DOM) consists of many organic compounds and plays an important role in contaminant transport in the ecosystem. However, the effects of different extraction conditions on contents of different DOM components are poorly understood.We extracted DOM from three soils using different extraction times, solid to liquid ratios(SLR), and extraction solution(KCl)concentrations, and evaluated the extractions using three-dimensional excitation-emission matrix(EEM) fluorescence spectroscopy.The sum of the contents of the main DOM components(protein-, fulvic-, and humic-like compounds) increased by 0.6–3.5, 2.5–3.9,and 0.11–0.37 times(P < 0.05) when SLR decreased from 1:2 to 1:10, the extraction solution concentration increased from 0.01 to 1.5 mol L^(-1), and extraction time increased from 10 to 300 min, respectively. The three-dimensional EEM fluorescence spectroscopy is a useful tool to characterize the components of DOM and evaluate DOM extraction in soils. 展开更多
关键词 提取条件 溶解有机物 三维荧光 土壤 评价 矩阵 发射 激发
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Shale Oil Solvent Extraction of Central Jordan El-Lajjun Oil Shale 被引量:1
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作者 Hani M. Alnawafleh Feras Y. Fraige 《Journal of Analytical Sciences, Methods and Instrumentation》 2015年第3期35-43,共9页
The extraction of the organic matter (OM) from oil shale (OS) can be achieved by several processing techniques. Normally, these techniques can remove high proportion of the organic material contained in oil shale. In ... The extraction of the organic matter (OM) from oil shale (OS) can be achieved by several processing techniques. Normally, these techniques can remove high proportion of the organic material contained in oil shale. In this work, organic solvents extraction experiments were implemented to investigate the effect of various parameters on Jordanian El-Lajjun oil shale extractability. Results indicate that the approximate organic matter content in studied El-Lajjun oil shale is 17.48%, and 75% of OS sample particles diameters are less than 270 μm. The grain size has minor effect on shale oil extraction via organic solvents. Among eleven solvents used, the highest yield is obtained via the tetrahedrofuran (THF), whereas, with the use of solvent mixtures, the highest bitumen yield is obtained through the mixture of THF and toluene. The solvation variability is related to mode of extraction and various physicochemical factors such as extraction temperature, pressure, solvent type and mixing time, which result in different OM yield. The results indicate that the solvent extraction could be potential for shale oil extraction from Jordanian El-Lajjun OS under certain conditions of temperature, pressure and solvent type used. 展开更多
关键词 Oil SHALE organic matter BITUMEN SOLVENT extraction El-Lajjun JORDAN
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Efficiency Evaluation of Extraction Methods for Analysis of OCPs and PCBs in Soils of Varying TOC
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作者 Ulrike Mülow-Stollin Petra Lehnik-Habrink +2 位作者 Stephanie Kluge Wolfram Bremser Christian Piechotta 《Journal of Environmental Protection》 2017年第6期693-713,共21页
Organochlorine pesticides and polychlorinated biphenyls are toxic, carcinogenic, and have a high potential for bioaccumulation. Due to their stability, they are still considered an environmental problem even though th... Organochlorine pesticides and polychlorinated biphenyls are toxic, carcinogenic, and have a high potential for bioaccumulation. Due to their stability, they are still considered an environmental problem even though the use of most of them has been phased out several decades ago. Soil is a matrix which can retain these contaminants to a great extent. This ability is often associated with the total organic carbon content (TOC). In order to judge the pollution status of soil and to make monitoring data more easily comparable a simple, yet robust extraction method is needed. Agitation solid-liquid-extraction is well suited for this purpose. However, the influence of TOC on the analyte recovery has to be known. For the presented study, 12 organochlorine pesticides and 7 polychlorinated biphenyls were spiked into four model soils with organic carbon contents between 1.6% - 13.3%. The matrices were extracted using solid-liquid extraction between 45 minutes and 16 hours. For comparison, all soils were also extracted using pressurised liquid extraction and Soxhlet extraction. After clean-up the extracts were measured using a gas chromatography-mass spectrometry (GC-MS) system. Statistical analysis of the results implied that the TOC content of the soils did not have significant influence on the extraction efficiency. A longer solid-liquid extraction time did not necessarily increase analyte recovery: Extraction for one hour resulted in 88% recovery while 16 hour extraction led to 89%. Thus, the efficiency of all the methods was comparable for all model soils. Additional investigations regarding GC liner performance highlighted the need for isotopically labelled standards during the analysis of thermolabile pesticides. 展开更多
关键词 POP Soil organic matter SOLID-LIQUID extractION Pressurised Liquid extractION
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Effect of Additional Feed Supplement Fermentation Shrimp Waste Extract on Digestibility in Sentul Chicken Growth Phase
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作者 Abun Abun Nurhalisa +1 位作者 Kiki Haetami Deny Saefulhadjar 《Journal of Zoological Research》 2022年第3期13-19,共7页
This study aims to determine the effect of adding feed supplements of fermented shrimp waste extract in the ration on the digestibility of local chicken rations in the growth phase.The research was carried out in Jati... This study aims to determine the effect of adding feed supplements of fermented shrimp waste extract in the ration on the digestibility of local chicken rations in the growth phase.The research was carried out in Jatinangor District as well as the Laboratory of Ruminant Animal Nutrition and Animal Feed Chemistry,Faculty of Animal Husbandry,Padjadjaran University,Sumedang.The method used in this study was experimental with a Complete Randomized Design(RAL).The data were analyzed by fingerprint test(ANOVA)with further tests using the Dunnet test.The object of this study consisted of 20 Sentul chickens raised from the age of 1 day to 12 weeks,divided into 5 treatments and 4 tests.The treatment consists of P0=Basal ration without the addition of feed supplement fermented shrimp waste extract,P1=Basal ration+0.5%feed supplement fermented shrimp waste extract,P2=Basal ration+1.0%feed supplement fermented shrimp waste extract,P3=Basal ration+1.5%feed supplement fermented shrimp waste extract,and P4=Basal ration+2.0%feed supplement fermented shrimp waste extract.The changes observed are the digestibility of dry matter,the digestibility of organic matter,and the digestibility of proteins.The results showed that the addition of feed supplements for fermented shrimp waste extract had a significantly different influence on the digestibility of dry matter,the digestibility of organic matter,and the digestibility of protein.This study concludes that the addition of a feed supplement of 2%fermented shrimp waste extract in the ration can produce a high ration digestibility value for Sentul chicken in the growth phase. 展开更多
关键词 Fermented shrimp waste extract Dry matter digestibility organic matter digestibility Protein digestibility Sentul chickens
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四川盆地普光地区深层地下油田卤水溶解性有机质组成特征研究
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作者 王昊 张耀玲 +3 位作者 杨克利 刘鑫 董亚萍 李武 《盐湖研究》 CAS CSCD 2023年第4期68-77,共10页
采用C18、PPL、HLB三种固相萃取材料对四川盆地普光地区一处油田卤水中的DOM进行了富集分离并采用FTIR和Py-GC/MS对所分离的DOM进行了表征。结果表明,PPL和HLB的组合吸附剂对油田卤水DOM的富集效率较好,C18富集效率最低。所研究油田卤水... 采用C18、PPL、HLB三种固相萃取材料对四川盆地普光地区一处油田卤水中的DOM进行了富集分离并采用FTIR和Py-GC/MS对所分离的DOM进行了表征。结果表明,PPL和HLB的组合吸附剂对油田卤水DOM的富集效率较好,C18富集效率最低。所研究油田卤水DOM中主要含有有机酸、含硫化合物、芳香族化合物、碳水化合物、脂肪族化合物以及含氮有机物等。其中含硫有机物和有机酸所占比例较多。这可能是由于该区域海相层系中发育着多种类型的含硫物质,可通过生物地球化学作用而生成种类繁多的含硫有机物。而有机酸作为微生物生长的营养物质,又在一定程度上促进了含硫有机物的形成。通过比较发现,地质条件/成因以及水质参数等因素都会影响油田卤水DOM的组成特征。针对不同地域及不同形成机制的油田卤水中DOM的结构组成做系统性研究,可为后续DOM的有效处理提供科学依据。 展开更多
关键词 固相萃取 溶解性有机质 油田卤水
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Influencing factors and significance of organic and inorganic nitrogen isotopic compositions in lacustrine sedimentary rocks 被引量:1
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作者 Juan Chen Jianfa Chen +5 位作者 Lipeng Yao Qingyong Luo Shengbao Shi Jianping Chen Lei Zhu Zeya Chen 《Geoscience Frontiers》 SCIE CAS CSCD 2023年第2期27-39,共13页
Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous... Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous Qingshankou Formation(QF,86–92 Ma)in Songliao basins,by evaluating the organic and inorganic nitrogen isotopic compositions rather than only organic or bulk nitrogen isotopic compositions.The results indicate that the nitrogen isotope values of bulk rock(δ^(15)N_(bulk))in the non-metamorphic stage are significantly different from that of kerogen,which challenge the conceptual framework of sedimentary nitrogen isotope interpretation.Theδ^(15)N_(bulk)from the YF and QF were lower than their respective the nitrogen isotope values of kerogen(δ^(15)N_(ker)),with offsets up to5.1‰,which have the inverse relationship for the metamorphosed rock.Thermal evolution did not significantly modify the d15N of bulk rock and kerogen.The d15N of sediments from the YF(δ^(15)N_(bulk),1.6‰–5.6‰)were lower than that of rock from the QF(δ^(15)N_(bulk),10.2‰–15.3‰).The nitrogen isotope values of silicate incorporated nitrogen(δ^(15)N_(sil))were slightly lower than those of the d15Nker in the YF and obviously lower for the QF.The fact that different nitrogen cycles occur in the YF and QF due to the different depositional redox conditions leads to different isotopic results.The YF water environment dominated by oxic conditions is not conducive to the occurrence of denitrification and anammox,and no abundant N2 loss leads to the relatively lightδ^(15)N_(bulk).In the stratified water for the QF,redox transition zone promotes denitrification and anammox,resulting in the heavyδ^(15)N_(bulk)of rock and promotes the DNRA,resulting in heavyδ^(15)N_(ker)and lowδ^(15)N_(sil). 展开更多
关键词 Nitrogen isotopes Bulk rock KEROGEN extracted organic matter Thermal maturation Nitrogen biogeochemical cycle
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萃取车间有机废气治理方案比较分析 被引量:1
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作者 阴世超 任兆成 《绿色矿冶》 2023年第3期73-77,共5页
萃取车间生产过程中产生大量有机废气,主要成分是萃取剂和溶剂油,具有高挥发性,易燃,具有一定的毒性,会给大气造成污染。本文介绍了目前萃取车间采用的通风技术,着重介绍了净化塔-活性炭吸附方案、RTO蓄热燃烧方案、高分子材料吸收+蒸... 萃取车间生产过程中产生大量有机废气,主要成分是萃取剂和溶剂油,具有高挥发性,易燃,具有一定的毒性,会给大气造成污染。本文介绍了目前萃取车间采用的通风技术,着重介绍了净化塔-活性炭吸附方案、RTO蓄热燃烧方案、高分子材料吸收+蒸汽再生方案的原理、装置及适应性,并根据实际情况给出有机废气净化方案选择的建议。 展开更多
关键词 萃取 有机物 净化方案 RTO 高分子材料
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环境固体样品中多种甾体激素的同步检测方法及条件优化
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作者 冯慧 徐欣 +4 位作者 彭鹏 王馨凝 钟琴 邹华 张云 《中国环境监测》 CAS CSCD 北大核心 2023年第2期214-224,共11页
采用超声辅助萃取-吸附剂净化-液相色谱-串联质谱同步检测环境固体样品中22种甾体激素,比较筛选了超声辅助萃取的有机溶剂和净化萃取液的吸附剂。结果表明,使用甲醇/乙腈/乙腈对固体样品中的甾体激素分别进行3次超声辅助萃取效果最佳,在... 采用超声辅助萃取-吸附剂净化-液相色谱-串联质谱同步检测环境固体样品中22种甾体激素,比较筛选了超声辅助萃取的有机溶剂和净化萃取液的吸附剂。结果表明,使用甲醇/乙腈/乙腈对固体样品中的甾体激素分别进行3次超声辅助萃取效果最佳,在0~150 mg/mL投加量范围内,N-丙基乙二胺粉末能有效减少浓缩萃取液中有机质的干扰并获得最高回收率,石墨碳粉末的有机质去除效果最好,但同时也造成目标物的显著损失,而硅胶粉末对有机质的去除效果不明显,因此选用N-丙基乙二胺粉末为萃取液的净化吸附剂,推荐使用量为150~400 mg/mL,在此优化条件下,22种甾体激素的标准曲线线性良好,方法检出限为0.025~0.696μg/kg,加标回收率达到63.5%以上,且操作简便、耗时短,适用于各种复杂环境固体样品的检测分析。 展开更多
关键词 甾体激素 超声辅助萃取 萃取液净化 固体样品 有机质干扰
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水溶有机质难萃取组分组成分析
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作者 禚笑村 胡浩杰 +3 位作者 何晨 李玉果 张未来 史权 《中国科技论文》 CAS 北大核心 2023年第9期935-941,共7页
为表征水溶有机质(dissolved organic matter,DOM)在传统固相萃取(solid phase extraction,SPE)中难萃取组分的分子组成,采用轻度催化加氢的方法对一河流支流水样的原水、SPE洗脱液和萃余液DOM进行加氢脱氧反应,在保留分子主体碳骨架不... 为表征水溶有机质(dissolved organic matter,DOM)在传统固相萃取(solid phase extraction,SPE)中难萃取组分的分子组成,采用轻度催化加氢的方法对一河流支流水样的原水、SPE洗脱液和萃余液DOM进行加氢脱氧反应,在保留分子主体碳骨架不发生破坏的前提下降低化合物极性。应用气相色谱质谱联用(gas chromatography-mass spectrometry,GC-MS)和负离子电喷雾电离源(electrospray ionization,ESI)结合静电场轨道离子阱质谱(Orbitrap mass spectrometry,Orbitrap MS)分析产物分子结构和组成。结果表明,SPE难萃取组分的分子组成与洗脱液相比具有明显差异。SPE洗脱液主要富集中等极性化合物,而残留在萃取柱上未被有效洗脱的主要是游离态正构烷烃和烷基环己烷、烷基苯等非极性和弱极性化合物,SPE萃余液组分主要包括结合态酯类和包含氮杂环、多环芳香族碳骨架的强极性化合物。 展开更多
关键词 水溶有机质(DOM) 固相萃取(SPE) 分子组成 气相色谱质谱联用 加氢脱氧
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Removal of Natural Organic Matter by Forward Osmosis Membrane: Flux Behaviour and Foulant Characterization 被引量:2
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作者 XIA Shengji YANG Ruilin ZHANG Xinhuan NI Muzi WAN Yukun YAO Lijuan GAO Naiyun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2015年第2期308-314,共7页
Fouling of cellulose triacetate(CTA) forward osmosis(FO) membranes by natural organic matter(NOM) was studied by means of a cross-flow fiat-sheet forward osmosis membrane system. The NOM solution was employed as... Fouling of cellulose triacetate(CTA) forward osmosis(FO) membranes by natural organic matter(NOM) was studied by means of a cross-flow fiat-sheet forward osmosis membrane system. The NOM solution was employed as the feed solution(FS), and a sodium chloride solution(3 tool/L) was used for the draw solution(DS). The process was conducted at various temperatures and cross-flow velocities. The flux decline was investigated with 3 h forward osmosis operation. The substances absorbed on the membranes were cleaned by ultrasonic oscillation of the fouled membranes and were characterized by methodologies including fluorescence excitation-emission matrices (EEMs) and liquid chromatography with an organic carbon detector(LC-OCD), and the variations of membrane properties were also investigated by Fourier transform infrared spectrometer(FTIR) and a contact angle meter. It was noted that the rejection efficiency of NOM is remarkable and that ultrasonic oscillation is an effective method to extract the NOM fouled on the CTA membranes after FO process. A higher cross-flow velocity and lower temperature benefit the anti-fouling capacity of the membrane significantly. Although humic substances accounted for the majority of the NOM, aromatic proteins and amino acids were the main fouling components on the membranes, with symbolic FTIR peaks at 2355, 1408 and 873 cm^-1. The present surface foulant made the membranes becoming more hydrophilic, as demonstrated by a significant decrease in contact angle(ranging from 20% to 46%) under all the operation conditions. 展开更多
关键词 Drinking water Forward osmosis FOULING Natural organic matter extraction Membrane flux
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不同方法提取的生物质炭可溶性有机物性质研究 被引量:1
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作者 郑小东 李翔 +5 位作者 魏岚 黄连喜 陈伟盛 黄玉芬 黄庆 刘忠珍 《中国农学通报》 2023年第12期61-68,共8页
为了揭示不同提取方法对生物质炭来源可溶性有机物(DOM)性质的影响,以生物质炭为研究对象,采用多种提取剂、提取方式提取生物质炭DOM,分析其碳含量及化学组成特征。结果表明:低温生物质炭中碱提取物DOC含量较高(15.6~40.0 g/kg),而高温... 为了揭示不同提取方法对生物质炭来源可溶性有机物(DOM)性质的影响,以生物质炭为研究对象,采用多种提取剂、提取方式提取生物质炭DOM,分析其碳含量及化学组成特征。结果表明:低温生物质炭中碱提取物DOC含量较高(15.6~40.0 g/kg),而高温生物质炭中盐提取物较高(0.27~7.04 g/kg)。酸提取物DOM化学组成较为简单,表现为SUVA254、SUVA280值较低,且玉米秆生物质炭中酸提取物亲水性DOM比例(44.6%~73.6%)显著高于水和碱提取物(11.0%~53.2%、0.30%~31.4%)。碱提取物DOM化学组成较复杂,其SUVA_(254)、SUVA_(280)值较高,同时玉米秆生物质炭中碱提取物疏水性DOM比例(68.6%~99.7%)显著高于酸和盐提取物(26.4%~55.4%、0%~46.9%)。该研究揭示了提取剂在生物质炭DOM提取方法中的重要性,而提取方式对其性质影响不显著,可为生物质炭DOM提取方法的选择提供参考。 展开更多
关键词 生物质炭 可溶性有机物 提取方法 化学组成 土壤重金属污染修复
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Biodegradation of dissolved organic carbon in soil extracts and leachates from a temperate forest stand and its relationship to ultraviolet absorbance 被引量:7
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作者 XU XingKai LUO XianBaot +1 位作者 JIANG SongHua XU ZhongJun 《Chinese Science Bulletin》 SCIE CAS 2012年第8期912-920,共9页
The amount and biodegradability of dissolved organic carbon (DOC) in forest floors can contribute to carbon sequestration in soils and the release of CO 2-C from soil to the atmosphere.There is only limited knowledge ... The amount and biodegradability of dissolved organic carbon (DOC) in forest floors can contribute to carbon sequestration in soils and the release of CO 2-C from soil to the atmosphere.There is only limited knowledge about the biodegradation of DOC in soil extracts and leachates due to the limitations inherent in degradation experiments.Differences in the biodegradation of DOC were studied in forest soil extracts using cold and hot water and 4 mmol/L CaCl 2 solution and in soil leachates sampled under different conditions over a wide range of DOC concentrations.From these results,we developed a simple and rapid method for determining the biodegradable organic C in forest floors.The hot water extracts and CaCl 2 extracts after CH 3 Cl fumigation contained higher concentrations of biodegradable organic C than the cold water extracts and CaCl 2 extracts before fumigation,with rapid DOC degradation occurring 24-48 h after incubation with an inoculum,followed by slow DOC degradation till 120-168 h into the incubation.During a 7-d incubation with an inoculum,the variation in DOC degradation in the different soil extracts was consistent with the change in special UV absorbance at 254 nm.Relatively higher levels of biodegradable organic C were detected in soil leachates from the forest canopy than in forest gaps between April and October 2008 (P <0.05).Relatively lower concentrations of DOC and biodegradable organic C were observed in soil leachates from N-fertilized plots during the growing season compared with the control,with the exception of the plot treated with KNO 3 at a rate of 45 kg N ha 1 a 1.Around 77.4% to 96.3% of the variability in the biodegradable organic C concentrations in the forest floors could be accounted for by the initial DOC concentration and UV absorbance at 254 nm.Compared with the conventional inoculum incubation method,the method of analyzing UV absorbance at 254 nm is less time consuming and requires a much smaller sample volume.The results suggest that the regression models obtained using the initial DOC concentration and UV absorbance can provide a rapid,simple and reliable method for determining the biodegradable organic C content,especially in field studies involving relatively large numbers of samples. 展开更多
关键词 土壤浸出液 生物降解性 溶解有机碳 垃圾渗滤液 水提取物 温带森林 紫外吸收 可生物降解
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Selective Extraction Methods for Aluminium,Iron and Organic Carbon from Montane Volcanic Ash Soils 被引量:3
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作者 B.JANSEN F.H.TONNEIJCK J.M.VERSTRATEN 《Pedosphere》 SCIE CAS CSCD 2011年第5期549-565,共17页
Montane volcanic ash soils contain disproportionate amounts of soil organic carbon and thereby play an often underestimated role in the global carbon cycle.Given the central role of Al and Fe in stabilizing organic ma... Montane volcanic ash soils contain disproportionate amounts of soil organic carbon and thereby play an often underestimated role in the global carbon cycle.Given the central role of Al and Fe in stabilizing organic matter in volcanic ash soils,we assessed various extraction methods of Al,Fe,and C fractions from montane volcanic ash soils in northern Ecuador,aiming at elucidating the role of Al and Fe in stabilizing soil organic matter(SOM).We found extractions with cold sodium hydroxide,ammonium oxalate/oxalic acid,sodium pyrophosphate,and sodium tetraborate to be particularly useful.Combination of these methods yielded information about the role of the mineral phase in stabilizing organic matter and the differences in type and degree of complexation of organic matter with Al and Fe in the various horizons and soil profiles.Sodium tetraborate extraction proved the only soft extraction method that yielded simultaneous information about the Al,Fe,and C fractions extracted.It also appeared to differentiate between SOM fractions of different stability.The fractions of copper chloride-and potassium chloride-extractable Al were useful in assessing the total reactive and toxic Al fractions,respectively.The classical subdivision of organic matter into humic acids,fulvic acids,and humin added little useful information.The use of fulvic acids as a proxy for mobile organic matter as done in several model-based approaches seems invalid in the soils studied. 展开更多
关键词 土壤有机碳 铝组分 火山灰 萃取方法 山地 提取方法 土壤有机质
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