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171.
粉煤灰改性吸附材料处理沥青烟气   总被引:4,自引:0,他引:4  
分析了粉煤灰改性后的物质基础 ,采用吸附法 ,利用改性粉煤灰作为吸附剂对沥青烟气进行处理 ,通过实验研究得到一定的运行参数 ,为沥青烟气的处理提供了理论依据  相似文献   
172.
The real-time detection of the mixing states of polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs in ambient particles is of great significance for analyzing the source, aging process, and health effects of PAHs and nitro-PAHs; yet there is still few effective technology to achieve this type of detection. In this study, 11 types of PAH and nitro-PAH standard samples were analyzed using a high performance-single particle aerosol mass spectrometer (HP-SPAMS) in lab studies. The identification principles ‘parent ions’ and ‘mass-to-charge (m/z) = 77’ of each compound were obtained in this study. It was found that different laser energies did not affect the identification of the parent ions. The comparative experiments of ambient atmospheric particles, cooking and biomass burning emitted particles with and without the addition of PAHs were conducted and ruled out the interferences from primary and secondary organics on the identification of PAHs. Besides, the reliability of the characteristic ions extraction method was evaluated through the comparative study of similarity algorithm and deep learning algorithm. In addition, the real PAH-containing particles from vehicle exhaust emissions and ambient particles were also analyzed. This study improves the ability of single particle mass spectrometry technology to detect PAHs and nitro-PAHs, and HP-SPAMS was superior to SPAMS for detecting single particles containing PAHs and nitro-PAHs. This study provides support for subsequent ambient observations to identify the characteristic spectrum of single particles containing PAHs and nitro-PAHs.  相似文献   
173.
Metal complexation by natural ligands is important for metal transport and distribution in surface and ground water. The goal of the work was to study the ligand exchange rate for two important metal ions in natural aquatic systems (Al, Fe) was determined using EDTA and natural organic matter (NOM) of humic type as ligands. After adding EDTA to a solution containing metal-NOM complexes, these complexes dissociated and metal-EDTA complexes were formed. Metal-NOM complexes were separated from metal-EDTA complexes with the help of size-exclusion chromatography and detected by on-line inductively coupled plasma-mass spectrometry (ICP-MS). Injecting the samples into the system over time after addition of EDTA allowed us to measure the rate of the exchange of NOM by EDTA. The experiments could be well described with a first-order rate law assuming that the dissociation of the metal-NOM complexes is the rate-determining step. The exchange rate of Fe was found to be faster than that of Al. This corresponds well with the exchange rate of water molecules from the coordination sphere of the metal ions, which is also faster for Fe than for Al. Furthermore, the UV and the fluorescence signal of the chromatograms were measured. The results indicate that no disaggregation of NOM molecules took place, although about 75-85% of the aggregate-forming metal ions exchanged NOM by EDTA in their coordination sphere. This suggests clearly the fundamental role of NOM in colloidal transport of metals and in their bioavailability.  相似文献   
174.
固相微萃取气相色谱法测定水样中的苯胺、吡啶   总被引:10,自引:0,他引:10  
应用PDMS/DVB固相微萃取探头,结合GC/FID测定水中的苯胺、吡啶.优化了萃取温度、萃取平衡时间、pH等条件.该方法对苯胺和吡啶的检测限分别为0.050、0.065 mg/L,相对标准偏差6.44%~8.67%,具有快速、准确和方便等优点.  相似文献   
175.
根据蜂窝断面内循环三相生物流化床内混合液的连续性方程、动量方程和能量方程,利用Fluent软件对反应器内的流动状况进行了数值模拟.采用Fluent的前处理软件Gambit完成流化床的三维模型,利用Fluent主程序解析计算,并利用后处理软件实现计算结果的显示.模拟计算结果获得了反应器内静压力、静压差的变化规律,得到了液体循环速度、气含率沿纵向及横断面的分布.  相似文献   
176.
污泥与高浓度有机废物厌氧消化反应中的产气量   总被引:3,自引:0,他引:3  
研究了高温/中温两相厌氧消化反应器系用以同时处理污泥与不同高浓度有机废物时产气及产甲烷的变化特性。结果表明,气体及甲烷主要是在第二段的中温消化反应器内产生。当中温消化反应器的有机负荷VS为1.65 ̄3.10kg/m^3d时,稳态条件下的平均产气量为1.958 ̄4.020m^3/d,气体中甲烷的平均组成为65% ̄73%,甲烷的比产率为0.397 ̄0.511m^3/kgVS。  相似文献   
177.
Despite a rapid expansion over the past decade in the reliance on intrinsic bioremediation to remediate petroleum hydrocarbon plumes in groundwater, significant research gaps remain. Although it has been demonstrated that bacterial sulfate reduction can be a key electron accepting process in many petroleum plumes, little is known about the rate of this reduction process in plumes derived from crude oil and gas condensates at cold-climate sites (mean temperature <10 degrees C), and in complex hydrogeological settings such as silt/clay aquitards. In this field study, sulfate was injected into groundwater contaminated by gas condensate plumes at two petroleum sites in Alberta, Canada to enhance in-situ bioremediation. In both cases the groundwater near the water table had low temperature (6-9 degrees C). Monitoring data had provided strong evidence that bacterial sulfate reduction was a key terminal electron accepting process (TEAP) in the natural attenuation of dissolved hydrocarbons at these sites. At each site, water with approximately 2000 mg/L sulfate and a bromide tracer was injected into a low-sulfate zone within a condensate-contaminant plume. Monitoring data collected over several months yielded conservative estimates for sulfate reduction rates based on zero-order kinetics (4-6 mg/L per day) or first-order kinetics (0.003 and 0.01 day(-1)). These results favor the applicability of in-situ bioremediation techniques in this region, under natural conditions or with enhancement via sulfate injection.  相似文献   
178.
The Llobregat basin is a Mediterranean fluvial system with major agricultural, urban and industrial impacts. We combined chemical quantification by liquid chromatography–mass spectrometry with electrospray interface (LC-ESI-MS) and the recombinant yeast assay (RYA) assays to estimate the loads of endocrine disrupting compounds (EDCs) along the basin. Chemical analysis revealed maximum concentrations (at μg l−1 level) of alkylphenols at the lower course of the Llobregat River, which correlated with high levels of estrogenic activity detected by RYA. Analysis by RYA and LC-ESI-MS of influent and effluent waters from four sewage treatment plants (STP) discharging into the basin showed the removal of 80–95% of EDCs by STP treatment. Chemical analysis data and RYA data showed a quasi-linear correlation, demonstrating the complementariness of both methods. Our data suggest that the concentrations of the analysed compounds were enough to explain the total estrogenicity of water and STP samples from the Llobregat basin.  相似文献   
179.
SPME-GC/MS法测定垃圾渗沥液中双酚A   总被引:3,自引:3,他引:0  
建立了固相微萃取-气相色谱质谱联用法测定垃圾渗沥液中双酚A的方法,并用于广州大田山垃圾渗沥液中双酚A含量的测定。对影响萃取的参数进行了优化,实验选用涂层厚度为85μm聚丙烯酸酯(PA)萃取纤维,在搅拌速度为1200r/min、NaCl浓度为20%、pH2.0和室温条件下萃取60min。方法的线性范围为0.1~100μg/L,检出限为0.03μg/L,精密度为6.6%。应用本方法监测了广州大田山垃圾渗沥液中BPA的含量在生物法处理过程中的变化情况。  相似文献   
180.
探讨“烟塔合一”技术在环评中大气环境的防护距离   总被引:1,自引:0,他引:1  
归纳"烟塔合一"项目评估的共性要求,在分析德国模式不能充分反映特定条件下对近距离保护目标影响的基础上,阐明了环境防护距离设置的必要性,并就目前所采取环境防护距离计算方法及部分项目风洞试验结果进行解析,提出相关建议。  相似文献   
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