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排序方式: 共有74条查询结果,搜索用时 31 毫秒
61.
Application of activated carbon in the characterization of nitrogen compounds and phthalates in a landfill leachate 总被引:1,自引:0,他引:1
Lisiane dos Santos Freitas 《Microchemical Journal》2004,78(1):61-64
The goal of this work was the development of a methodology based on solid phase extraction (SPE) to characterize nitrogen compounds and phthalates from landfill leachate samples. Activated carbon (AC) was used to extract all the organic compounds from the samples. The samples were collected in Porto Alegre-South Brazil. As the AC used had small particle size, it was impossible to use it in the form of packed cartridges; hence, it had to be applied in a batch mode. The desorption of the organic compounds from the AC was made by sonication with dichloromethane. The extract was analyzed by gas chromatography with mass spectrometric detection (GC-MSD). Some aspects of the validation of the methodology were also established. Several nitrogen compounds and phthalates were identified in the samples, proving the efficiency of this method with regard to the selectiveness for these substances. 相似文献
62.
Yamamoto A Yasuhara A Kodama S Matsunaga A Suzuki S Mohri S Yamada M 《Journal of separation science》2004,27(4):325-329
An ion-exclusion chromatographic method with on-line desalinization for the determination of volatile fatty acids in landfill leachates is described. Highly sensitive conductivity detection of the organic acids was achieved by using dilute p-hydroxybenzoic acid solution as an eluent. Interference with mineral acids was reduced by treatment with barium chloride solution prior to desalinization. A silver-loaded cation-exchange guard column for the desalinization was installed in series with the analytical column to avoid the contamination of organic acids. This method features detection limits of 0.01 mg L(-1) formic acid, 0.02 mg L(-1) acetic acid, 0.05 mg L(-1) propionic acid, and 0.1 mg L(-1) butyric acid, respectively, with an injection of 20 microL sample. Application of the on-line desalinization LC method is illustrated for leachate samples from a Japanese sanitary landfill. 相似文献
63.
Membrane separations are finding greater use in wastewater treatment because of their efficiency. In order to prove the effectiveness
of membrane filtration an applicability study is carried out. Nanofiltration and reverse osmosis membranes are tested under
quite different conditions to reduce the chemical oxygen demands (COD) of wastewaters to meet the Council Directive 76/464/EEC
release limit. Two kinds of real wastewaters were selected for the investigation. The wastewaters represent extreme different
circumstances since the difference between their COD is two orders of magnitude. All of the membranes tested can be applied
either to the treatment of wastewater of high COD (pharmaceutical wastewater) or wastewater of low COD (dumpsite leachate),
since the different conditions do not change the membrane characteristics. The experimental data show that none of the membranes
can decrease the COD to the release limit in one step. However, if two-stage filtrations (nanofiltration followed by reverse
osmosis) are accomplished for both of the wastewaters, a total COD reduction of 94% can be achieved. With the application
of the two-stage filtration the COD of the wastewater of low COD can be decreased below the release limit but in case of wastewater
of the high COD further treatment will be required.
相似文献
64.
垃圾渗沥液中难降解有机污染物的Fenton混凝处理 总被引:10,自引:0,他引:10
垃圾渗沥水;上流式厌氧污泥床;废水处理;垃圾渗沥液中难降解有机污染物的Fenton混凝处理 相似文献
65.
阴阳离子双隔膜三室电解槽电渗析处理垃圾渗滤液 总被引:4,自引:0,他引:4
采用阴阳离子双隔膜三室电解槽,将电渗析技术与Fenton试剂法结合,去除垃圾渗滤液中氨氮和CODCr。垃圾渗滤液中的氨氮通过电渗析技术富集到阴极液中,随后用化学沉淀法加以去除。同时,在铁阳极上生成的Fe2+离子,与滴加入阳极液中的H2O2反应生成Fenton试剂,降解有机物,降低CODCr。实验结果表明,模拟废水中的氨氮透过率达80%,垃圾渗滤液中氨氮浓度和CODCr由原来的1982和2248 mg/L分别降至200和127 mg/L。 相似文献
66.
电极面积对老龄垃圾渗滤液为底物的微生物燃料电池性能影响 总被引:1,自引:0,他引:1
电极面积对老龄垃圾渗滤液为底物的微生物燃料电池性能影响 《燃料化学学报》2015,43(8):1011-1017
构建生物阴极型双室微生物燃料电池,处理老龄垃圾渗滤液。研究了阳极与阴极面积比值对微生物燃料电池产电能力和对老龄垃圾渗滤液处理效果的影响。结果表明,阳极与阴极面积比为1:2、2:2、2:1的3组生物阴极型微生物燃料电池输出电压分别为408、452、396mV,最大电功率密度分别为145.73、237.65、136.50mW/m3,内阻分别为350、200、400Ω,COD的去除率分别为21.18%、20.20%、22.31%。3组微生物燃料电池运行30d后,垃圾渗滤液中氨氮、硝酸盐氮、亚硝酸盐氮浓度均下降,其中,氨氮去除率分别为80.88%、73.61%和66.17%,其去除效果与产电性能相关。 相似文献
67.
Juris Burlakovs Fabio Kaczala Kaja Orupõld Amit Bhatnagar Zane Vincevica-Gaile Vita Rudovica 《International journal of environmental analytical chemistry》2015,95(7):609-617
Landfill mining applied in reclamation at the territories of old dump sites and landfills is a known approach tended to global economic and environmental benefits as recovery of metals and energy is an important challenge. The aim of this study was to analyse the concentration of several metallic elements (Ca, Cu, Cr, Fe, K, Mn, Pb, Zn) in the fine fraction of waste derived in the landfill and to compare the results of measurements obtained by field-portable equipment with the data gained by advanced analytical tools. Atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS) were used for the quantitative detection of metallic elements at the laboratory; whereas field-portable X-ray fluorescence spectrometry (FPXRF) was applied for rapid sample characterisation in the field (on-site). Wet digestion of samples (fine fraction of waste at landfill) was done prior analytical procedures at the laboratory conditions, but FPXRF analysis was performed using raw solid samples of waste fine fraction derived in the Kudjape Landfill in Estonia. Although the use of AAS and ICP-MS for the measurements of metals achieves more precise results, it was concluded that precision and accuracy of the measurements obtained by FPXRF is acceptable for fast approximate evaluation of quantities of metallic elements in fine fraction samples excavated from the waste at landfills. Precision and accuracy of the results provided by express method is acceptable for quick analysis or screening of the concentration of major and trace metallic elements in field projects; however, data correction can be applied by calculating moisture and organic matter content dependent on sample matrix as well as special attention must be paid on sample selection and homogenisation and number of analysed samples. 相似文献
68.
B. Bayerl K.-H. Heinrich S. Rummel M. Wahren 《Isotopes in environmental and health studies》2013,49(1):48-49
Tracers can be used to monitor emissions of leachate from landfills in order to detect hydrological pathways and to evaluate environmental pollution. We investigated the stable carbon isotope ratio (δ13C–Σ CO 2) in dissolved inorganic carbon and tritium (3H) in water, in addition to the tracers of pollution commonly found in relatively high concentrations in leachate, such as chloride (Cl), organic matter (COD), nitrogen (total and NH4–N), iron (Fe), electrical conductivity (EC) and pH. The sampling was performed at seven landfills in the south-eastern part of Norway during a period of 5 years. The objective was to evaluate the potential for tracing leachate in the environment with emphasis on groundwater pollution. By measuring the δ13C–Σ CO 2 in leachates, groundwaters and surface waters, the influence of leachate can be identified. The value of δ13C–Σ CO 2 varied from?5.5 to 25.9 ‰ in leachate, from?25.4 to 14.7 ‰ in groundwater and from?19.7 to?13.1 ‰ in creeks. A comparison of the carbon isotope ratio with COD, EC and the concentrations of total and NH 4–N, Cl and Fe showed that δ13C–Σ CO 2 is a good tracer for leachate due to higher sensitivity compared to other parameters. The mean concentrations of all the studied parameters were higher in the leachate samples; however, only the carbon isotope ratio showed significant differences between all the groups with strong and middle pollution and samples with low pollution, showing that it can be used as a convenient tracer for leachate in groundwater and surface water. The carbon isotope ratio showed strong correlation between nitrogen, EC and bicarbonate, but not with pH. Tritium was only sporadically found in measureable concentrations and is not considered as a suitable tracer at the sampled locations. 相似文献
69.
J. Feldmann A. V. Hirner 《International journal of environmental analytical chemistry》2013,93(2-4):339-359
Abstract Speciation of volatile metals and metalloids in the environment is extensively described in literature. In order to investigate unstable volatile organometallics, on-line coupling of GC with ICP-MS was used. Preliminary results for gases of sewage sludge fermentation at thermophilic and mesophilic conditions are compared with the metal and metalloid speciation in landfill gases. In each case 20 L gas were sampled by cryogenic trapping. The species were identified by element-specific detection either by retention time of standards or by calculation of the boiling point correlation. Characteristic of the separation is the linear correlation of boiling point (bp/°C) versus retention time (rt/min) (bp = 6.39?rt -109.2, r2 = 0.9926). The amounts of total volatile elements are estimated by semi-quantification. Cd, Sn. Hg, Pb (sewage gas) and Se, Te, Hg, Pb (landfill gas) were determined in the range of ng m?3 level; As, Sb, Te and Bi (sewage gas) and As, Sn, Sb and Bi (landfill gas) in the μg m?3 level range. 相似文献
70.
A simple and reliable method has been established for determination of cis and trans-1,3-dichloropropene (1,3-DCP) in water by headspace solid-phase microextraction (HS-SPME) then GC–ECD. An experimental design
with two steps was performed to determine the best experimental conditions for extraction of the 1,3-DCP isomers. First, a
26−2 fractional factorial design was conducted to screen for significant conditions. Second, a central composite design (CCD)
was performed to optimise the variables. The best experimental extraction conditions were: polydimethylsiloxane–divinylbenzene
(PDMS–DVB)-coated fibre, 20-min extraction time, 12 °C extraction temperature, 300 g L−1 NaCl, and 20 mL headspace volume in 40-mL vial. Under these conditions the method detection limit (MDL) was 0.5 ng L−1 for cis-1,3-DCP and 1.0 ng L−1 for trans-1,3-DCP. The method quantification limit (MQL) was 1.2 ng L−1 for cis-1,3-DCP and 3.0 ng L−1 for trans-1,3-DCP. For both isomers the relative standard deviation (RSD) for analysis of 50 ng L−1 or 0.5 μg L−1 of the isomer mixture was less than 8%. When the proposed method was applied to surface (river) water and tapwater samples
from Gipuzkoa province (Spain) the target analytes were not detected. The method was also used to investigate the presence
of the isomers in leachates from agricultural soil. A mixed solution was added to samples of two different soils and 1,3-DCP
isomers were quantified in leachate obtained from the samples. 相似文献