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861.
金鉴明 《中国人口.资源与环境》1993,3(1):22-24
我国矿产资源丰富且矿种较齐全,但人均占有量偏低。生产技术水平低,资源消耗较大,造成环境污染严重。加强矿产资源开发中的环境保护工作是经济持续发展的战略措施。 相似文献
862.
亚甲蓝褪色反应测定水中痕量锰 总被引:2,自引:0,他引:2
本文提出和建立了一个新的催化动力学测定痕量锰的方法。它是基于在醋酸-醋酸钠介质中,锰对高碘酸钾氧化亚甲蓝褪色反应所具有的催化效应。在最佳条件下,用固定时间法,可测5—80ng/27ml范围内的锰。应用于水样测定,获得满意结果 相似文献
863.
Sarita Sinha 《Environmental monitoring and assessment》1999,57(3):253-264
The metal accumulation potential of Bacopa monnieri L. was assessed under simulated laboratory conditions. This study was carried out in mixed metals (Cu, Cd, Pb, Cr, Mn) condition and repeated exposures in artificial contaminated soil. The growing shoots were planted in garden subsoil containing 3, 16, 32, 64, 160 M each of the above metals. After 8 weeks, plants were refeeded to three times higher concentrations of each metal than initially used to assess the maximum accumulating potential of the metals. The accumulation of the metals by the root and shoot was concentration and duration dependent. The metal accumulation was considerably higher in the fine root than in the shoot and showed the following order : Mn > Cr > Cu > Cd > Pb. The plants showed high tolerance to the metals as no visible phytotoxic symptom was produced after 8 weeks. However, as a result of combined metal toxicity, chlorophyll content was reduced by 62% after 12 weeks. The highest metal concentration was lethal to the plant at 16 weeks. In view of their high tolerance, the plants of B. monnieri may be considered for the amelioration of industrially-polluted wetlands experiencing regular flushing of wastewaters. 相似文献
864.
增敏碘量法同时测定微量Mn(Ⅱ)、 Mn(Ⅶ)、 Cr(Ⅲ)、 Cr(Ⅵ) 总被引:1,自引:0,他引:1
介绍了用增敏碘量法同时测定微量的Mn(Ⅱ)、Mn(Ⅶ)、Cr(Ⅲ)和Cr(Ⅵ)。将样品中的Mn(Ⅶ)和Cr(Ⅵ)用Na2SO3预先还原,在pH为3.0的醋酸盐介质中对Mn(Ⅱ)和Cr(Ⅲ)用过量KIO4氧化(当用H2P2O2-7掩蔽Cr(Ⅲ)时,只有Mn(Ⅱ)被氧化),过剩的IO-4用钼酸盐掩蔽,加入KI后,以Na2S2O3滴定游离出的I2。此法对Mn的测定范围为29~14706μg/L,相对标准偏差为0.31%~1.18%;对Cr的测定范围为59~10294μg/L,相对标准偏差为0.36%~1.12%。此法与常规滴定法测定Mn和Cr相比,分别可增敏20倍和12倍 相似文献
865.
Abdul-Wahab SA Worthing MA Al-Maamari S 《Environmental monitoring and assessment》2005,107(1-3):313-327
The aim of this work is to characterize the mineral phases present in the atmosphere at three locations in northern Oman. Samples of atmospheric particles were collected using a high volume sampler. Three indoor and one outdoor location were chosen in this investigation. Sampling locations included a residential house located nearby the cement plant, a residential house located nearby a refinery plant, and a residential house located at Al-Suwayq residential area. Indoor air was sampled from these three houses. Moreover, for the Al-Suwayq residential house, sampling was also taken outside the house for comparison. The dust samples were analysed for their microanalysis characterization and their mineral contents as well. The microanalysis enabled us to identify the metals present in the particles. Furthermore, the mineralogical analysis of the sample filters showed the presence of quartz as the principal phase inside the house of Al-Suwayq, whereas quartz, dolomite, and gypsum were common phases outside the house. In the residential house nearby the cement plant, it was found that calcite, quartz, dolomite and goethite were the principal phases whereas the particles collected from the house nearby the refinery composed primarily of dolomite and calcite. The airborne dust collected at the refinery and Al-Suwayq were probably sourced in the natural environment and mobilised by natural processes. However, at the cement factory the crushing and grinding of limestone during the industrial process has contributed significantly to the airborne dust load. Generally, the information obtained in this study will be invaluable as no data for the mineral content of atmospheric dust existed in the Oman. 相似文献
866.
四川呷村多金属矿床成因矿物学研究 总被引:1,自引:0,他引:1
呷村矿床是典型的“黑矿型”含金、稀土富银多金属矿床.笔者对黄铁矿、闪锌矿、方铝矿、黝铜矿等主要矿物的物理性质、光学性质和化学成分作了系统研究.研究表明:①矿石的矿物种类繁多,含稀土的矿物具有特殊意义;②黄铁矿的结构为探讨该矿床的成矿环境和矿床成因提供了重要信息;③矿物性质的变化主要与微量元素含量和成矿物理化学条件有关;④矿物微量元素含量在矿区空间变化的规律对找矿与勘探具有指导意义;⑤方铅矿不是载Ag矿物.黄铁矿Co、Ni含量并不高,Co/Ni<1,这些是本矿床的独特之处. 相似文献
867.
文章旨在探索巨大芽孢杆菌(Bacillus megaterium)、黑曲霉(Aspergillus niger)和灰色链霉菌(Streptomyces griseus)3种菌株、6种培养顺序在添加铁、铝、锰氧化物情况下对混有木质素白浆土腐殖质组成的差异影响.采用室内培养法,在针铁矿、三羟铝石和δ-MnO_2参与条件下,通过6种菌株培养顺序的设置,探讨其对木质素白浆土混料腐殖质组成的影响.结果表明:基于针铁矿添加条件,在以巨大芽孢杆菌为Ⅰ期培养菌株时更有利于白浆土腐殖化系数(CHA/CFA)的促进.而在针铁矿和δ-MnO_2添加条件下,A.niger→S.griseus→B.megaterium的培养顺序更有利于白浆土胡敏酸(HA)向富里酸(FA)的转化.基于三羟铝石添加条件,灰色链霉菌为Ⅰ期培养菌株时更有利于白浆土CHA/CFA的促进,而以巨大芽孢杆菌为Ⅰ期培养菌株时可使CHA/CFA降低;除S.griseus→A.niger→B.megaterium外的5种菌株培养顺序,δ-MnO_2均能有效促进白浆土HA的降解、使其分子结构更加简单;无论哪一菌株培养顺序,针铁矿均有利于微生物对混料胡敏素(Hu)的矿化,δ-MnO_2可使混料总有机碳(TOC)发生较大程度矿化;与对照相比,δ-MnO_2亦可促进微生物对混料水溶性物质(WSS)的消耗,且对可提取腐殖酸(HE)的形成有促进作用. 相似文献
868.
Samuel N Addy 《Resources Policy》1998,24(4):229-239
After almost two decades of decline, Ghana's mineral sector has rebounded significantly and is currently the main foreign exchange earner. Gold mining is the principal activity within the sector and accounted for 41 percent of total export earnings in 1996. This paper presents an overview of Ghana's mineral industry and covers mineral resources, production and reserves; mining investments; the role of mining in the economy; and the structure of the industry. An overview of the national mineral policy is also presented to depict the current regulatory and fiscal environment in which the industry operates. The spectacular reversal in mineral sector performance can be attributed to the adoption of World Bank recommendations in a new national mineral policy, the 1986 Minerals and Mining Law, aimed at revitalizing the sector. 相似文献
869.
870.