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311.
二氧化硫排放测算方法与控制对策探讨   总被引:1,自引:0,他引:1  
二氧化硫作为衡量企业减排成绩和环境效益的重要指标,其计算方法的选取尤为重要。通过对几种常用二氧化硫排放测算方法的研究及比较,选取了物料衡算法作为长庆油田公司第一采气厂天然气净化厂环境统计分析的基本计算依据,确定了二氧化硫排放问题的关键影响因素,同时从环境统计学角度给出了二氧化硫达标排放的控制指标及建议,为有效开展二氧化硫及其他污染物的排放问题研究,提供技术指导及方法依据。  相似文献   
312.
Currently HPLC/MS is the state of the art tool for environmental/drinking water perfluorooctane sulfonate (PFOS) monitoring. PFOS can bind to peroxisomal proliferator-activated receptor-alpha (PPARα), which forms heterodimers with retinoid X receptors (RXRs) and binds to PPAR response elements. In this bioassay free PFOS in water samples competes with immobilized PFOS in ELISA plates for a given amount of PPARα-RXRα. It can be determined indirectly by immobilizing PPARα-RXRα-PFOS complex to another plate coated with PPARα antibody and subsequent measuring the level of PPARα-RXRα by using biotin-modified PPARα-RXRα probes-quantum dots-streptavidin detection system. The rapid and high-throughput bioassay demonstrated a detection limit of 2.5 ng L−1 with linear range between 2.5 ng L−1 and 75 ng L−1. Detection results of environmental water samples were highly consistent between the bioassay and HPLC/MS.  相似文献   
313.
Polychlorinated-dibenzo-p-dioxins and -dibenzofurans (PCDD/Fs) were measured in soils and sediments from the Yellow Sea region. Korean soils and sediments mostly contained detectable PCDD/Fs and showed a widespread distribution among locations. Soil and sedimentary PCDD/Fs from China were comparable to or less than those in Korea. The patterns of relative concentrations of individual congeners in soils were different between the two countries, but similar in sediments. Sources of PCDD/Fs in China and Korea were found to be independent of each other and their distributions reflected matrix-dependent accumulation. Spatial distribution indicated some point sources in Korea while Chinese sources were more widespread and diffuse. PCDD/Fs measured in the coastal areas of the Yellow Sea were comparable to or less than those previously reported in for eastern Asia. However, ∑TEQs in soils and sediments were near to or, in some cases exceeded environmental quality guidelines.  相似文献   
314.
Polycaprolactone/tapioca starch/octadecylamine modified clay (OMMT) nanocomposites were successfully prepared by melt blending. X-ray diffraction and transmission electron microscopy (TEM) of the products showed that they are nanocomposites of a mixture intercalated and exfoliated types. In addition, the TEM also revealed that the OMMT layers are homogeneously distributed in the polymer matrix. The presence of 1 php of OMMT improved the compatibility of the polymers in the blends which consequently increased the tensile strength of the blend of more than 60% and elongation at break of more than 1,000%.  相似文献   
315.
采取固定床连续式水处理方式,实验研究了在固体催化剂作用下微量臭氧催化氧化深度处理地下煤气化废水的效果.结果表明,当处理COD为300 mg,/L左右的该类型废水时,加入微量臭氧,水处理装置COD去除率提高了45%,平均1 mg的臭氧处理了2.4 mg有机物;当废水COD为200 mg/L左右,进水速度为1 L/h时,最佳臭氧投加量为每升废水20 mg左右的臭氧,此时气水比为15:1左右;同时实验发现,不同COD的废水色度均可以被有效去除.通过与其他类似的实验研究比较发现,微量臭氧催化氧化技术具有成本优势.  相似文献   
316.
铝污泥吸附六价铬的特征和机理   总被引:1,自引:0,他引:1  
铝污泥是给水处理过程中不可避免的副产物,为了解其资源化利用作为吸附剂对Cr(Ⅵ)的吸附行为和吸附特征,本研究通过静态实验研究了铝污泥的水解特征、Cr(Ⅵ)在铝污泥上的吸附机理和影响因素。结果表明,(1)铝污泥表面的主要官能团为羟基、SO24-和Cl-;(2)铝污泥与Cr(Ⅵ)的吸附过程中,液相中Cr(Ⅵ)的浓度随吸附时间延长而降低(由20 mg/L降为15.42 mg/L),同时,液相中pH由6.01升高为7.06、SO24-由8.79 mg/L升高为11.40 mg/L、Cl-由10.54 mg/L升高为11.88 mg/L,这一结果表明,HCrO4-与铝污泥表面的羟基、SO24-、Cl-等官能团交换,其吸附机理为配体交换;(3)pH是影响Cr(Ⅵ)在铝污泥上的吸附量的主要因素,当pH由4.0升高至10.0时,吸附容量由7.63 mg/g下降为0.70 mg/g。实验表明,铝污泥作为一种新型的Cr(Ⅵ)吸附剂具有较高吸附能力和应用前景,并为优化吸附工艺提供了技术支撑。  相似文献   
317.
The highest values in annual TSP distributions fall below the best-fit, log-normal straight line more than one would expect from ordinary sampling statistics but not dramatically so. The lowest values in annual TSP distributions overwhelmingly fall below the best-fit, log-normal straight line. The most highly improbable high values above the best-fit line in such distributions are very questionable and probably do not represent true air quality values. The most improbable cases of highest values falling below the best-fit, log-normal line are the result of data artifacts at the opposite end of the data distribution. They do not represent low probabilities and probably do represent true air quality values. The most improbable low values are all of highly doubtful validity.  相似文献   
318.
Gas chromatography with nitrogen phosphorus detector (GC-NPD) was applied to the simultaneous determination of 15 organophosphorus and 6 organonitrogen pesticides residues in Angelica sinensis. The pesticides were extracted by microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) techniques, respectively. The experimental variables were optimized through orthogonal array experimental design. Cleanup of extracts was performed with column chromatography using florisil and neutral aluminum as the sorbents. The determination of pesticides in the final extracts was carried out by GC-NPD. Under optimized conditions, the average recoveries obtained from MAE and UAE are in the range of 75.1–129% and 70.6–129%, respectively, and the relative standard deviations of MAE and UAE were 3.1–10.6% and 1.0–17.8%, respectively.  相似文献   
319.
以包头钢铁(集团)有限责任公司高炉煤气冷凝水为处理对象,采用强化混凝法进行静态混凝沉淀对比实验。实验结果表明,当聚合氯化铝加入量为20mg/L、高分子纳米除氯剂加入量为2.0mL/L时,处理后出水SS小于10mg/L,浊度小于10NTU,氯离子去除率在80%以上,而且对废水中的其他离子也有一定的去除效果,出水水质基本接近工业冷却循环水回用指标。  相似文献   
320.
Novel renewable polyols based on limonene were synthesized using thiol-ene “click” chemistry. These limonene based polyols were structurally characterized using wet methods (hydroxyl number, acid value and viscosity), gel permeation chromatography and spectroscopic methods. The results indicated that high yield of polyols from limonene based materials can be obtained using thiol-ene reaction. These limonene based polyols were used successfully for preparation of rigid polyurethane foams. These foams had regular shape cells and uniform cell size distribution. Thermal studies on these foams indicated that foams were thermally stable up to 250 °C. The glass transition temperature of the foams was higher than 200 °C. These rigid polyurethane foams had high compressive strength and the highest compressive strength of 195 kPa was observed. These foams have good physical–mechanical characteristics and could be suitable for all the applications of rigid polyurethane foams such as thermal insulation of freezers, storage tanks for the chemical and food industries, and packing materials for food industries.  相似文献   
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