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341.
Concentrations, distribution, and bioaccumulation of synthetic musks in the Haihe River of China 总被引:4,自引:0,他引:4
Seven typical synthetic musks (SMs) in the samples from the surface water, sediment and fish of the Haihe River were measured. The SM concentrations in the sediment and surface water of the Haihe River were significantly lower than those in the Dagu Drainage River and Chentaizi Drainage River (p < 0.05). Along the flow direction, the SM concentrations in surface water and sediment tended to increase from the upstream to the downstream of Dagu Drainage River. The Bioaccumulation factors (BAFs) of galaxolide (HHCB) and tonalide (AHTN) were calculated at high levels in the muscles of crucian carp, common carp, and silver carp. Most of the biota-sediment accumulation factors (BSAFs) for HHCB and AHTN were higher than 1.7, suggesting magnification possibly exist in the musk bioaccumulations of the three fishes in the Haihe River. No significant differences in HHCB/AHTN ratios were observed among the water, fish, and sediment samples (p > 0.05). However, the HHCB/AHTN values in the Haihe River were much lower than those in the Dagu Drainage River and Chentaizi Drainage River (p < 0.05). Compared with several typical persistent organic pollutants (POPs), the musk concentrations were higher or comparable in the Haihe River. 相似文献
342.
嘉兴南湖整治后水质对微生物种群生态分布的影响 总被引:1,自引:0,他引:1
2002年4月至2003年4月,在南湖水面设了6个采样点,对湖中微生物的分布进行调查,年平均值为:异养细菌2752个/mL、纤维素分解菌326个/mL、氨氧化菌393个/mL、亚硝酸氧化菌305个/mL、硝酸盐还原菌1507个/mL、脱氮菌55个/mL、有机磷分解菌36.5个/mL、大肠杆菌平均≥5000个/L,有机磷分解菌的分布和湖中总磷含量存在正相关性;全年细菌量以11月份最高,8,9份最低。从各样点分离出108个菌株对其进行鉴定,结果有12个属,假单胞菌属是南湖水中的优势菌,占细菌总数的34.2%。水中总磷、氨氮、挥发性酚含量虽然低于综合整治前,但仍然偏高。南湖为富营养化的湖泊。 相似文献
343.
Determination of polybrominated diphenyl ethers in soil and sediment from an electronic waste recycling facility 总被引:6,自引:0,他引:6
In this study samples of ten species of fish were analyzed for concentrations of organochlorine pesticides, PCBs and heavy metals (Pb, Cd, and Cu). Fish were captured using electric fishing on ten sites along the Dr?me river (Rh?ne-Alpes region). Quantitative determination of the organochlorine and PCBs compounds was performed by gas chromatography-electron-capture detection (GC-ECD). The concentrations of heavy metals were determined by atomic absorption spectrophotometry. Samples contained detectable concentrations of lindane, PCBs, and heavy metals but at concentrations below the maximum residue limit (MRL). Non-parametric statistical analysis was performed to distinguish groups of sites with different levels of contamination. PCBs concentrations increased along the river with four groups of sites significantly different from each other. Cadmium concentrations were below the MRL. Lead contamination showed two groups significantly different and a repartition similar to PCBs. Copper contamination was correlated with the localization of vineyards. We assessed the potential effects of contamination the otter (Lutra lutra). The concentrations of all pollutants analyzed in fish sampled in this study are lower than the threshold values described in literature. The Dr?me river is relatively unpolluted river, and the establishment of otter populations should not be affected by pollution. 相似文献
344.
The study of operating variables in soil washing with EDTA 总被引:7,自引:0,他引:7
Zou Z Qiu R Zhang W Dong H Zhao Z Zhang T Wei X Cai X 《Environmental pollution (Barking, Essex : 1987)》2009,157(1):229-236
This study discusses the operating variables for removal of metals from soils using EDTA, including the type of EDTA, reaction time, solution pH, dose, temperature, agitation, ultrasound and number of extractions. For As, Cd, Cu, Pb and Zn, the removal efficiency order was: H4-EDTA > Na2EDTA > (NH4)2EDTA. At low EDTA concentrations the removal increased progressively with increasing dose while above 0.4 mmol/g only small increases in extraction efficiency were observed. EDTA induced a two-step process including a rapid desorption within the first hour, and a gradual release in the following hours. The extraction efficiency of metals decreased with increasing pH in the range of 2-10. Consecutive extractions using low concentrations were more effective than a single extraction with concentrated EDTA if the same dose of EDTA was used. 相似文献
345.
346.
采用软模板法制备中孔炭电极,利用比表面及孔径分析仪、循环伏安法对自行制备的电极与市售进口电极的性能指标进行表征,比较二者的性能差异;探讨施加电压、进液流量和进液电导率等因素对电吸附效果的影响,确定最佳操作条件,并分别用两种等面积的电极处理含盐废水,进行脱盐性能的比较.研究结果表明,采用软模板法制备的碳电极,其BET比表面积1 517 m2/g,最可几孔径2.04 nm,平均孔径3.36 nm,比电容50.13 F/g.实验装置安装一对电极,电极面积共400 cm2,电吸附的最佳操作条件为施加电压1.2 V、进水流量30 mL/min,NaCl浓度664 mg/L(电导率1 000 μS/cm),对含盐废水电导率的去除率为57.80%,对NaCl的饱和吸附量为7.03 mg/g.自制电极对废水中的TDS的吸附量为9.96 mg/g,高于市售进口电极,总硬度的去除率高于市售进口电极40%左右. 相似文献
347.
三峡水库进入蓄水期后,入库流速和泥沙粒径降低,为细颗粒泥沙的絮凝过程创造了水动力条件。为了探究细颗粒泥沙絮凝过程的最佳环境条件及其对内源磷赋存与分布的影响,该文研究了泥沙粒径与浓度、pH、温度和水动力强度等环境因子对细颗粒泥沙絮凝及内源磷迁移与转化的影响。研究结果表明,泥沙粒径越小,絮凝度越大,对磷的吸附能力也越强,但其解吸潜力也越大。泥沙浓度与絮凝强度、磷吸附与解吸能力呈正比,且非磷灰石无机磷(NAIP)是发生解吸的主要磷形态。中性环境不利于细颗粒泥沙絮凝,当pH=5时,总磷吸附量和磷灰石无机磷(AIP)解吸量相对较大;当p H>8时,磷吸附能力减弱,而NAIP的解吸过程增强。温度升高能促进泥沙颗粒絮凝及其对磷的吸附作用,当解吸作用占主导地位时,温度增加也会促进解吸过程。有限强度的水体扰动形成的水动力条件可促进细颗粒泥沙絮凝及其对磷的吸附,但也为磷的解吸创造了有利条件。 相似文献
348.
Ren M Zhou L Peng P Chen de Y Cai Y 《Journal of environmental monitoring : JEM》2011,13(10):2880-2885
The atmospheric deposition of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) was investigated at four locations in different suburban and urban functional districts of Guangzhou City. The annual deposition fluxes of total PBDD/Fs (eight 2,3,7,8-substituted tetra- to hexa-BDD/Fs) were in the range of 36-51 (mean 46) pg m(-2) day(-1), and the corresponding TEQ fluxes were estimated to range between 7.9 and 11.3 (mean 10.3) pg I-TEQ m(-2) day(-1), indicating a noticeable pollution level. The deposition fluxes of PBDD/Fs during the wet season were 2-4 times as high as those during the dry season. Both rainfall and temperature positively correlated with PBDD/F deposition fluxes. Ambient gas/particle partition coefficients (K(p)) were predicted with SPARC. It appears seasonal variations of PBDD/F deposition fluxes were influenced by meteorological parameters and the local usage of brominated flame retardants (BFRs). The congener profiles of PBDD/Fs at four locations were similar either spatially or temporally, indicating that the main PBDD/F emission sources were similar to one another. Seasonal variations and congener patterns of PBDD/Fs indicated the possible sources included electronic waste recycling, industrial waste incinerators and products containing BFRs. 相似文献
349.
350.