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701.
Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources, chemical mechanisms, and transport processes of air pollution and carbon emissions in China, and for regulatory and control purposes. This study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent years. China has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of effort. The manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved, and a technical & production system that can meet the requirements of routine monitoring activities has been initiated. It is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.  相似文献   
702.
镉对不同生态型水稻的毒性及其在水稻体内迁移转运   总被引:7,自引:0,他引:7  
采用溶液培养方法研究镉(Cd)对两种不同生态型水稻的毒性影响以及Cd在水稻体内的转运.结果表明,粳稻品种杨辐粳7号比籼稻品种K优818对Cd毒害反应更敏感.两种生态型水稻品种的根系对Cd的吸收积累差异比较大,在10 μmol·L-1 Cd浓度下生长3~14 d,杨辐粳7号根系中Cd浓度比K优818高44.5% ~ 99.5%,当Cd处理时间达到14 d时,K优818茎叶中Cd积累量为杨辐粳7号的1.6倍(P<0.05).K优818的Cd转运系数显著(P<0.05)高于杨辐粳7号,是杨辐粳7号的1.3 ~2.3倍,且随着Cd处理时间的延长K优818的Cd转运系数呈上升趋势,而杨辐粳7号的Cd转运  相似文献   
703.
中国地表水酸沉降临界负荷的区划   总被引:1,自引:1,他引:1  
为了解中国地表水体对酸沉降的响应情况,应用基于酸度平衡的稳态法研究中国地表水酸沉降临界负荷区划.结果表明,中国地表水硫沉降临界负荷呈较明显的地带分布.其中,大兴安岭北端水体的硫沉降临界负荷最低,大部分小于2 keq·(hm2·a)-1,东北北部部分水体和秦岭-淮河以南大部分地区水体的硫沉降临界负荷介于2~10 keq·(hm2·a)-1之间,其余地区水体硫沉降临界负荷普遍大于10 keq·(hm2·a)-1.地表水酸度临界负荷的地区分布和数值大小类似于硫沉降临界负荷由于中国地表水酸度临界负荷普遍大于2 keq·(hm2·a)-1,因此大部分地表水对酸化并不敏感,近期内不易酸化.  相似文献   
704.
The effects of addition of calcium hydroxide on aluminum sulphate(or alum) coagulation for removal of natural organic matter(NOM) and its subsequent effect on the formation potentials of two major types of regulated disinfection byproducts(DBPs),haloacetic acids(HAAs) and trihalomethanes(THMs),have been examined.The results revealed several noteworthy phenomena.At the optimal coagulation pH(i.e.6),the coagulation behavior of NOM water solutions versus alum dose,showed large variation and a consequent great change in the formation potentials of the DBPs at certain coagulant doses.However,with addition of a relatively small amount of Ca(OH) 2,although the zeta potential of coagulated flocs remained almost the same,NOM removal became more consistent with alum dose.Importantly,also the detrimental effect of charge reversal on NOM removal at the low coagulant dose disappeared.This resulted in a steady decrease in the formation potentials of DBPs as a function of the coagulant dose.Moreover,the addition of Ca(OH) 2 broadened the pH range of alum coagulation and promoted further reduction of the formation potentials of the DBPs.The enhancement effects of Ca(OH) 2 assisted alum coagulation are especially pronounced at pH 7 and 8.Finally,synchronous fluorescence spectra showed that the reduction in DBPs formation potential by Ca(OH) 2-assisted alum coagulation was connected to an enhanced removal of small hydrophobic and hydrophilic HA molecules.Ca(OH) 2-assistance of alum coagulation appeared to increase substantially the removal of the hydrophilic HA fraction responsible for HAAs formation,prompting further reduction of HAA formation potentials.  相似文献   
705.
石油炼制行业新旧污染物排放标准的差异   总被引:1,自引:0,他引:1       下载免费PDF全文
付鹏  潘峰  莫欣岳  马岩  段超越 《化工环保》2015,35(5):526-530
分别介绍了旧标准GB 8978—1996《污水综合排放标准》、GB 16297—1996《大气污染物综合排放标准》和新标准GB 31570—2015《石油炼制工业污染物排放标准》的核心内容。从适用范围、排放限值和污染控制因子3个方面分析了石油炼制行业新旧污染物排放标准的差异。  相似文献   
706.
根据EPA 1311、HJ/T 299-2007、HJ/T 300-2007和HJ 557-2009等国内外不同标准,研究了深圳某垃圾焚烧发电厂垃圾焚烧飞灰的浸出毒性,探讨了六硫代胍基甲酸(sixthio guanidine acid,SGA)、二甲基二硫代氨基甲酸盐(sodium dimethyl dithio carbamate,SDD)和Ca(OH)2浓度对垃圾焚烧飞灰中重金属的固定性能的影响。研究结果表明,随着浸提液pH的降低,该厂焚烧飞灰中大部分金属元素的浸出量增大,焚烧飞灰浸出液中的Cd、Ni、Pb和Zn浓度分别超过国家危险废物鉴别标准(GB5085.3-2007)规定值的4.75倍、1.47倍、6.72倍和2.20倍,属于危险废弃物,必须进行稳定化处理。当固化剂SGA加入量为0.1 mol/kg时,稳定化后的重金属浸出浓度已经低于危险废物鉴别标准,且对Cd、Cr、Cu和Pb的固化性能优于SDD和Ca(OH)2;当固化剂SGA、SDD和Ca(OH)2加入量为0.5 mol/kg时,稳定化后的焚烧飞灰重金属浸出浓度均低于国家危险废物鉴别标准(GB 5085.3-2007)中的规定值。与SDD和Ca(OH)2相比,SGA对垃圾焚烧飞灰中重金属的固化处理更具有优势。  相似文献   
707.
To elucidate the air pollution characteristics of northern China, airborne PM_10(atmospheric dynamic equivalent diameter ≤ 10 μm) and PM_(2.5)(atmospheric dynamic equivalent diameter ≤ 2.5 μm) were sampled in three different functional areas(Yuzhong County,Xigu District and Chengguan District) of Lanzhou, and their chemical composition(elements, ions, carbonaceous species) was analyzed. The results demonstrated that the highest seasonal mean concentrations of PM_10(369.48 μg/m~3) and PM_(2.5)(295.42 μg/m~3) were detected in Xigu District in the winter, the lowest concentration of PM_(2.5)(53.15 μg/m~3) was observed in Yuzhong District in the fall and PM_10(89.60 μg/m~3) in Xigu District in the fall.The overall average OC/EC(organic carbon/elemental carbon) value was close to the representative OC/EC ratio for coal consumption, implying that the pollution of Lanzhou could be attributed to the burning of coal. The content of SNA(the sum of sulfate, nitrate,ammonium, SNA) in PM_(2.5)in Yuzhong County was generally lower than that at other sites in all seasons. The content of SNA in PM_(2.5)and PM_10 in Yuzhong County was generally lower than that at other sites in all seasons(0.24–0.38), indicating that the conversion ratios from precursors to secondary aerosols in the low concentration area was slower than in the area with high and intense pollutants. Six primary particulate matter sources were chosen based on positive matrix factorization(PMF) analysis, and emissions from dust, secondary aerosols, and coal burning were identified to be the primary sources responsible for the particle pollution in Lanzhou.  相似文献   
708.
采用水解酸化-UASB(上流式厌氧污泥反应床)-接触氧化-生物活性炭工艺对利福平废水进行了生化处理。结果表明:水解酸化可以有效提高废水的可生化性,大幅度提高后续的厌氧-好氧处理效果,工艺末端的生物活性炭深度处理可以有效的去除好氧出水的COD和色度,使得出水达到GB8978-1996《污水综合排放标准》的规定标准。  相似文献   
709.
为研究松花江哨口至松花江村江段的水环境容量,本文从浮游植物光合作用机理出发,利用连续3年多项指标实测资料,采用外包线法,初步确定一种浮游植物光合作用产氧率计算关系式。将这种方法应用于研究江段效果较好,经相关性检验,r=0.90,r>r0.01,相关性极显著。该计算式能否用于哨口至松花江村以外的江段,尚需进一步验证。  相似文献   
710.
The removal of four dissolved organic matter (DOM) fractions, non-acid hydrophobics, hydrophobic acids, hydrophilics and transphilics, was achieved by coagulation-UV/H2O2 oxidation in post-pharmaceutical wastewater (PhWW). Coagulation with Polyferric chloride (PFC), Polymeric ferric sulfate (PFS) and Polymeric aluminum ferric chloride (PAFC) was studied separately to evaluate the effects of the initial pH and coagulant dosage. The coagulation-UV/H2O2 oxidation method resulted in much higher reduction rates for dissolved organic carbon (DOC) (by 75%) and UV254 (by 92%) than coagulation or UV/H2O2 oxidation alone. The proportion of non-acid hydrophobics, hydrophobic acids, transphilics and hydrophilics removed by coagulation was 54%, 49%, 27% and 12 %, while the combined treatment removed 92%, 87%, 70% and 39%, respectively. Parallel factor analysis (PARAFAC) of fluorescence measurements revealed that the humic-like fluorescent component C4 showed the highest removal (by 44%) during the coagulation stage. After coagulation-UV/H2O2 treatment, the humic-like fluorescent component C3 had the highest removal (by 72%), whereas xenobiotic organic fluorescent components C1 and C4 remained recalcitrant to decomposition. Significant correlations (R2 > 0.8) between C1 and the hydrophobic acids and non-acid hydrophobics suggested the possibility of using fluorescence spectroscopy as an effective tool to assess variations in DOM fraction treatment efficacy in coagulation-UV/H2O2 systems. After the combined treatment, toxic inhibition of cellular activity by post PhWW decreased from 88% to 47% and biodegradability increased from 0.1 to 0.52.  相似文献   
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