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951.
YJT塔及其在三苯废气治理中的应用   总被引:1,自引:0,他引:1  
介绍了一种自行研制的YJT塔组合净化装置及其工艺,并简要阐述了有关注体力学参数,通过某制鞋厂的三苯废气治理表明,用零号柴油作吸收剂,其净化效率较高,经治理排放的废气浓度和排放速率均符合行业标准中的一级标准。  相似文献   
952.
宋云龙  张金松  郭小雅  朱佳  王丽  陶益  张丽 《环境科学》2017,38(8):3302-3311
2013年4月至2014年6月对典型调水供水型水库石岩水库蓝藻、绿藻和硅藻叶绿素a浓度[ρ(Chla)]及相环境因子进行监测,分析了ρ(Chla)时空分布特征,探讨了藻类与环境因子的相关关系.结果表明石岩水库ρ(TChla)为9.59~123.29μg·L~(-1),平均52.03μg·L~(-1),其中蓝藻ρ(Chla)为4.54~76.30μg·L~(-1),平均为28.39μg·L~(-1);硅藻ρ(Chla)为3.16~46.09μg·L~(-1),平均为15.02μg·L~(-1);绿藻ρ(Chla)为0.77~26.21μg·L~(-1),平均为8.62μg·L~(-1).2013年4~12月上旬以及2014年5~6月优势藻为蓝藻,其他时期硅藻占优势,绿藻全年处于较低水平.石岩水库ρ(Chla)空间异质性低,整体呈现由南向北逐渐降低的空间分布特征,汛期整个库区和高温无雨期南半库区存在蓝藻水华风险.径流污染是石岩水库藻类叶绿素a空间异质性的主要原因.相关分析和CCA分析显示:水温是3种藻类的首要影响因子,汛期径流量与蓝藻相关性极大.氮磷比与3种藻类负相关,磷是石岩水库藻类生长的限制性因子.蓝藻主要相关因子还包括TOC、TN、pH、透明度和硝酸盐氮,硅藻主要相关因子还包括硅酸盐、TOC、硝酸盐氮和COD,绿藻主要相关因子还包括TOC、COD、pH、透明度和硝酸盐氮.  相似文献   
953.
纳氏试剂比色法测定污水中氨氮,其蒸馏预处理过程存在耗时长、馏出液接收不便和操作繁琐等问题.文章对预处理及测定方法进行了优化,提出将水样蒸馏体积减少为50 mL,后期比色体积减少为25 mL,并去除硼酸吸收液,改为直接接收馏出液.经验证,其结果与国标方法无显著性差异,标样验证相对误差为-0.8%~0.9%,实际样品测定结果的相对标准偏差为0.9%~4.4%,加标回收率为94%~107%.优化的方法测量数据稳定,结果准确,在测定污水中氨氮具有实际应用意义.  相似文献   
954.
2017年春节期间广东省环境空气质量自动监测站的数据分析结果表明:春节假期广东省空气质量等级变化较大.除夕全省空气质量为良;初一,全省以良和轻度污染为主,粤东出现重度污染,粤西和粤北出现中度污染,可能与除夕夜烟花爆竹燃放有关;初二起,全省空气质量逐渐转为优良.首要污染物以PM2.5和O3为主.现有的NAQPMS和CMAQ空气质量预报模型在污染相对严重的初一表现较差,主要是因为数值模型未能考虑到烟花爆竹燃放等排放源的输入.  相似文献   
955.
生物质成型颗粒是《江门市能源发展"十三五"规划》中着力发展的能源之一.根据江门市燃生物质成型颗粒锅炉当前的使用状况和排污情况,分析总结了造成颗粒物和氮氧化物超标的原因主要为锅炉内部结构、燃烧操作以及燃生物质成型颗粒质量等.在此基础上,探讨改善江门市燃生物质成型颗粒锅炉污染的对策,提出了科学定位生物质成型颗粒,促进行业健康发展,加快各相关企业升级改造,藉此也为其他地区的燃生物质成型颗粒锅炉提供参考.  相似文献   
956.
This article aims to generate the environmental profile of Singapore's Semakau landfill by comparing three different operational options associated with the life cycle stages of landfilling activities, against a 'business as usual' scenario. Before life cycle assessment or LCA is used to quantify the potential impacts from landfilling activities, an attempt to incorporate localized and empirical information into the amounts of ash and MSW sent to the landfill was made. A linear regression representation of the relationship between the mass of waste disposed and the mass of incineration ash generated was modeled from waste statistics between years 2004 and 2009. Next, the mass of individual MSW components was projected from 2010 to 2030. The LCA results highlighted that in a 'business as usual' scenario the normalized total impacts of global warming, acidification and human toxicity increased by about 2% annually from 2011 to 2030. By replacing the 8000-tonne barge with a 10000-tonne coastal bulk carrier or freighter (in scenario 2) a grand total reduction of 48% of both global warming potential and acidification can be realized by year 2030. Scenario 3 explored the importance of having a Waste Water Treatment Plant in place to reduce human toxicity levels - however, the overall long-term benefits were not as significant as scenario 2. It is shown in scenario 4 that the option of increased recycling championed over all other three scenarios in the long run, resulting in a total 58% reduction in year 2030 for the total normalized results. A separate comparison of scenarios 1-4 is also carried out for energy utilization and land use in terms of volume of waste occupied. Along with the predicted reductions in environmental burdens, an additional bonus is found in the expanded lifespan of Semakau landfill from year 2032 (base case) to year 2039. Model limitations and suggestions for improvements were also discussed.  相似文献   
957.
To compare the inorganic chemical compositions of TSP(total suspended paniculate),PM_(10)(particulate matter with an aerodynamic diameter less than 10 μm) and PM_(2.5)(particulate matter with an aerodynamic diameter less than 2.5 μm) in southern and northern cities in China,atmospheric particles were synchronously collected in Dalian(the northern city)and Xiamen(the southern city) in spring and autumn of 2004.The mass concentrations,twenty-three elements and nine soluble ions were assessed.The results show that in Dalian,the mass concentrations of Mg,Al,Ca,Mn and Fe in spring were 4.0-10.1,2.6-8.0,4.1-12,1.2-3.6 and 2.9-7.9 times higher,respectively,than those in Xiamen.The dust storm influence is more obvious in Dalian in spring.However,in Xiamen,heavy metals accounted for 13.9%-17.9%of TSP,while heavy metals contributed to 5.5%-9.3%of TSP in Dalian.These concentrations suggest that heavy metal pollution in Xiamen was more serious.In addition,the concentrations of Na~+,Cl~-,Ca~(2+) and Mg~(2+) were higher in Dalian due to the influence of marine aerosol,construction activities and soil dust.The NO~(3-)/SO_4~(2-) ratios in Dalian(0.25-0.49) were lower than those in Xiamen(0.51-0.62),indicating that the contributions of vehicle emission to particles in Xiamen were higher.Coefficient of divergence values was higher than 0.40,implying that the inorganic chemical composition profiles for the particles of Dalian and Xiamen were quite different from each other.  相似文献   
958.
959.
Astroviruses are becoming a growing concern in veterinary and public health. Many astrovirus species are associated with enteric diseases have been described in both mammalian and avian hosts. In the present study, 23 fecal samples from diarrheic minks were collected in Liaoning and Shandong Province, and an investigation of astrovirus was performed using biochemical methods and RT-PCR assay with specific primers. A total of four mink astroviral isolates were detected from sick minks with diarrhea problems. Further sequencing and characterization of the partial ORF1b gene and ORF2 gene segments revealed low sequence identities (20.0–85.3 and 31.8–87.2 %) with known astroviral strains, indicating the emergence of a novel clade of astroviruses. Some new features of the astroviral genome have also been discovered. The phylogenetic tree revealed that all samples were distantly related to mink astrovirus and were closely related to chicken astroviruses and turkey astroviruses. MK/DL-1, MK/DL-2, MK/SD-1, and MK/SD-2 formed a new clade and were found to be more closely related to astroviruses from birds than to other mink strains, indicating past cross-species transmission and considerable zoonotic potential.  相似文献   
960.
考察了以RuCl3·3H2O为前驱物,以AC(颗粒活性炭)为载体制备Ru/AC时,焙烧氛围、焙烧温度、焙烧时间对Ru/AC催化活性的影响,并利用XPS(X-ray photoelectron spectra,X射线光电子能谱分析)、BET(brunner-emmet-teller method,比表面积测定)和SEM(scanning electronic microscopy,扫描电镜)等手段对样品进行了表征. 结果表明,不同焙烧氛围中制备的Ru/AC活性有较大差异:在N2焙烧氛围中,容易形成去除BrO3-的有效活性组分(RuO2);而在真空焙烧氛围中,几乎没有活性组分的产生;在H2-N2〔φ(H2)为1.5%,φ(N2)为98.5%〕氛围中焙烧,负载在AC上的活性组分有Ru0(单质钌)和RuO2. 焙烧温度对Ru/AC去除BrO3-的性能有着较为显著的影响,高温有利于AC的石墨化进程,载体性能得到优化;但焙烧温度过高(1 000 ℃)时,会产生金属颗粒团聚现象;最适宜的焙烧温度为900 ℃. Ru/AC的活性随着焙烧时间的延长呈先增后降的趋势;焙烧时间为3 h时,载体的比表面积和孔容积得到提高且有效活性组分能够均匀地分散在AC载体上. 综上,Ru/AC催化剂的最优焙烧条件:焙烧氛围为N2,焙烧温度为900 ℃,焙烧时间为3 h. 在该条件下制备的Ru/AC利于形成去除BrO3-的活性物质RuO2,并且其能够均匀地分布在AC载体上,使催化反应进行得更为彻底,可在2 h内将BrO3-全部去除.   相似文献   
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