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91.
92.
废旧锌锰电池生物淋滤-水热法制备纳米锰锌铁氧体 总被引:1,自引:2,他引:1
以氧化硫硫杆菌(A.thiooxidans)和氧化亚铁钩端螺旋菌(L.ferrooxidans)为混合淋滤菌株对废旧锌锰电池进行了生物浸提,并以获取的淋滤液为前驱体,采用水热法制备出系列锰锌铁氧体软磁材料(Mn_(1-x)Zn_xFe_2O_4,x=0.2~0.8);结合X射线衍射(XRD)、扫描电镜-能谱(SEMEDX)、振动样品磁强计(VSM)、透射电镜(TEM)、红外光谱(FT-IR)、热重-差热分析(TG-DTA)等表征手段对制备材料的结构、形貌、磁学性能和稳定性进行分析.结果表明,在5%固液比(质量体积比,5 g/100 mL,以下均表述为"5%固液比")下,经过5 d的外源酸调控生物浸提,分别获得了84.5%、63.2%的Zn、Mn浸出效率;当Zn∶Mn∶Fe=0.4∶0.6∶2.0(物质的量比,即x=0.4)时,制备的纳米级Mn_(0.6)Zn_(0.4)Fe_2O_4性能最优,属纯相的立方尖晶石结构,颗粒分布均匀,饱和磁化强度(M_s)、剩余磁化强度(M_r)和矫顽力(H_c)分别为68.9 emu·g~(-1)、4.7 emu·g~(-1)和53.6 Oe,具有热稳定性和耐酸碱性,有望成为一种新型的水处理磁性材料. 相似文献
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新型碳材料石墨烯,因其比表面积大,物理、化学特性优异,通常作为吸附剂或复合材料载体,用于难降解有机废水处理.载体石墨烯改性后,可优化复合材料性能,包括溶解性和可控性.基于复合材料制备,选取典型污染物废水,如染料废水、苯酚废水、农药废水,从吸附处理和催化降解两方面展开,简要介绍石墨烯复合材料的应用研究及作用效果,显示出复合材料可有效提高污染物降解效率,回用效果好.此外,石墨烯复合材料在回用及实际应用方面仍有待进一步研究. 相似文献
95.
本文介绍了炭催化剂吸附剂标准物质的研制过程。对标准物质的制备技术、均匀性检验、稳定性考察及定值和不确定度进行了逐项分析。采用活性炭浸渍、煅烧技术制得炭催化剂吸附剂标准物质。试验结果表明,该标准物质定值结果准确,均匀性、稳定性良好。铜含量的标准值为11.06%,扩展不确定度为0.13%。 相似文献
96.
Spent hydroprocessing catalysts from refineries have been classified as hazardous solid waste by the United States Environmental Protection Agency (USEPA), refiners must find a viable but economical solution to solve this serious environmental issue. Catalyst rejuvenation is an attractive option for minimizing the environmental problems associated with spent catalysts. In this study, a preliminary design for such a process and the corresponding economic analysis are performed to assess the proposed catalyst rejuvenation process for metal-fouled spent catalysts generated in residue hydroprocessing units. The scenarios used in the economic assessment are based on three options of process synthesis and two operator modes. It is found that the option of rejuvenating medium and lightly fouled spent catalyst produced by the refinery will be the best solution for refiners, both environmentally and economically. 相似文献
97.
98.
UV-catalytic treatment of spent caustic from ethene plant with hydrogen peroxide and ozone oxidation 总被引:1,自引:0,他引:1
YU Zheng-zhe SUN De-zhi LI Chang-hai SHI Peng-fei DUAN Xiao-dong SUN Guo-rong LIU Jun-xin 《环境科学学报(英文版)》2004,16(2):270-275
The performance of UV/H2O2, UV/O3 and UV/H2O2/O3 oxidation systems for treating spent caustic from an ethylene plant was investigated, in UV/H2O2 system, with the increase of H202 dosage, removal efficiencies of COD and the ratio of biochemical oxygen demand(BOD) to chemical oxygen demand(COD) of the effluent were increased and a better performance was obtained than the H2O2 system alone. In UV/H2O2 system, removal efficiency of COD reach 68% under the optimum condition, and BOD/COD ratio was significantly increased from 0.22 to 0.52. In UV/O3 system, with the increase of O3 dosage, removal efficiency of COD and BOD/COD ratio were increased, and a better performance was obtained than the O3 system alone. Under the optimum condition, removal efficiency of COD was 54%, and BOD/COD ratio was significantly increased from 0.22 to 0.48. In UV/H2O2/O3 system, COD removal efficiency was found to be 22.0% higher than UV/O3 system. 相似文献
99.
The cracking of styrene derivative polymers dissolved in decalin was conducted with metal-supported carbon catalysts under
an inert gas atmosphere to recover monosubstituted styrene or monosubstituted ethylbenzene in higher yields than is obtained
by pyrolysis, and to elucidate the detailed reaction mechanisms in the solvent. Poly-(4-methylstyrene), poly-(4-t-butylstyrene), poly-(α-methylstyrene), and polystyrene were used. In decalin without a catalyst, each polymer was decomposed
into the monomer, dimer, and trimer derived from the corresponding polymer except for poly-(α-methylstyrene), which was decomposed
into the monomer and styrene. By using metal-supported carbon, the olefinic compounds derived from the corresponding polymer
were thoroughly hydrogenated to the saturated form in a nitrogen atmosphere by a hydrogen transfer reaction from decalin,
which was simultaneously dehydrogenated to tetralin and naphthalene with the evolution of hydrogen gas. In comparison with
metal species, Pd- and Ru-supported carbon catalysts maintained the hydrogenation activity for a longer time and with a lower
evolution of hydrogen than Pt or Rh. The dehydrogenation of decalin was mainly observed not on the metal surfaces, but on
the carbon surfaces over Pd-supported carbon. Stabilization of the monomers will be able to suppress the coking which occurs
with repolymerization in long running process.
Received: July 19, 2000 / Accepted: March 16, 2001 相似文献
100.