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891.
以TiO2为载体,选取过渡金属元素Mn为活性组分,稀土金属元素Ce为活性助剂,采用分步共混法制备了Mn-Ce/TiO2催化剂(活性组分负载量16%),系统研究了TiO2载体的晶型和晶粒尺寸对催化剂脱硝活性的影响。实验结果表明:分别以锐钛矿型和金红石型TiO2为载体制备的催化剂,其低温脱硝活性相差不大,活性组分均以无定型态高度分散于载体中,以金红石型TiO2为载体制备的催化剂中部分TiO2转变为锐钛矿型;以不同晶粒尺寸TiO2载体制备的催化剂的低温脱硝活性相差较大,比表面积较大、晶粒尺寸较小的TiO2载体制备的催化剂,其脱硝活性低于晶粒尺寸较大的TiO2载体制备的催化剂。 相似文献
892.
Richao Cong Toru Matsumoto Wenchao Li He Xu Takamasa Hayashi Changjun Wang 《Journal of Material Cycles and Waste Management》2017,19(4):1423-1436
With the rapid economic development in China, the amount of plastic waste (PW) generated has greatly increased and much of the waste is currently not treated. To reduce greenhouse gas (GHG) emissions from recycling of PW, we estimated the PW flow and considered methods to improve the household PW recycling system in Tianjin by adjusting processes during transportation and establishing a PW recycling factory in Zi’ya Industrial Park. The goal of the study was to identify reasonable improvements for the recycling system and clarify the environmental load. Geographic information system (GIS) technology was used to simulate transport processes for comparing GHG emissions from the transport processes between the present case and an improved case. Life cycle assessment (LCA) was used to compare GHG emissions between a projected scenario and a baseline scenario. Estimated GHG emissions during transport processes in the improved case were reduced by about 12,197 t CO2 eq per year compared to the present case, equivalent to about 65.9 % of the total emissions in the present case. GHG emissions in the projected scenario were about 101,738 t CO2 eq less per year than the baseline scenario, equivalent to about 75.5 % of the total emissions in the baseline scenario. 相似文献
893.
Yibo Zhang Lina Liu Yifei Sun Rong Zhu Xingbao Gao Jingling Yang Zhiqiang Han Hui Wang 《Journal of Material Cycles and Waste Management》2017,19(4):1437-1445
Effects of carbon concentration and Cu additive in simulated fly ash (SFA) and real fly ash (RFA) on the formation of polychlorinated dibenzofurans (PCDFs), polychlorinated dibenzo-p-dioxins (PCDDs), chlorobenzenes, and polychlorinated biphenyls which were all regarded as persistent chlorinated aromatics in iron ore sintering were investigated. In the annealing process of SFA with various carbon contents, the yield of chlorinated aromatics and the I-TEQ obtained their maximum at 10 wt% carbon content. Active carbon in SFA acted as the carbon source as well as an adsorbent which led to higher production of PCDD/F in solid phase at 10 wt% carbon content. The increase of carbon content will be beneficial on the formation of 2,3,7,8-Chloro-substituted PCDF compared with 2,3,7,8-Chloro-substituted PCDD. In addition, the CuCl2·2H2O was a much more powerful catalyst in the formation of chlorinated aromatic compounds compared with elementary Cu, since it served as both a catalyst and a chlorine donor. However, the RFA behaved similarly with SFA with elementary Cu in the formation of chlorinated aromatic compounds. The effect of carbon content and copper additives on formation of 2,3,7,8-chloro-substituted congeners displayed similar characteristics with the tetra- to octa-PCDD/F isomers and even the total PCDD/Fs. 相似文献
894.
Ying Zhang Yangyang Zhang Qiang Wang Xuerong Fan 《Journal of Polymers and the Environment》2017,25(3):526-532
Electro conductive hydrogels, consisting of chitosan (CS), hyaluronic acid (HA), and polypyrrole (PPy), were prepared via an in situ enzymic polymerization of pyrrole in the CS–HA hydrogel, using laccase as the catalyst. This CS–HA–PPy composite hydrogel showed good conductivity. The chemical structure and morphology of this conductive hydrogel were studied by Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction technique. For CS–HA–PPy and CH–HA hydrogel, the temperature at which fastest decomposition occurred was 260 and 244 °C, respectively. That means the thermal stability of CS–HA–PPy is better than CS–HA hydrogel. The conductive hydrogel also showed excellent swelling and deswelling behaviors. 相似文献
895.
采用固相合成法制备了Zr掺杂TiO_2(Zr-TiO_2),运用XRD技术对其进行了表征,并将其用于水中头孢氨苄的光催化降解,通过单因素实验及正交实验优化了光催化反应条件。结果表明:制备的Zr-TiO_2为锐钛矿型介孔材料,孔径约为8.12 nm;各因素对头孢氨苄去除率的影响由大到小依次为光照时间、Zr-TiO_2投加量、初始头孢氨苄质量浓度;在Zr-TiO_2投加量为1.5 g/L、初始头孢氨苄质量浓度为10 mg/L、溶液pH为7.0、光照(300 W UV)时间为1.5 h的优化条件下,头孢氨苄去除率高达99.46%;Zr-TiO_2光催化剂的重复使用性能良好。 相似文献
896.
897.
以絮状活性污泥为接种污泥,采用人工配制的模拟生活污水,分别在气提式序批反应器(SBAR)和序批式活性污泥反应器(SBR)中成功地培养出了成熟的好氧颗粒污泥.SBAR和SBR中的好氧颗粒污泥都具有稳定的基本形态结构,其微生物主要由杆菌和球菌组成,对COD的去除率可达到93%左右.对NH+4-N的去除率可达到98%以上.SBAR中好氧颗粒污泥的粒径主要分布、污泥体积指数(SVI)、比耗氧速率(SOUR)、TN去除率和TP去除率分别为0.45~2.00 mm、19.97 mL/g、47.68 g/(kg·h)、82%和65%;而SBR中好氧颗粒污泥的粒径主要分布、SVI、SOUR、TN去除率和TP去除率分别为0.18~1.00 mm、29.12 mL/g、43.21 g/(kg·h)、58%和50%.相对而言,SBAR更有利于好氧颗粒污泥的培养和运行. 相似文献
898.
899.
900.
通过恒温振荡平衡法研究了Pb~(2+)在针铁矿上的等温吸附和吸附动力学特征,探讨了吸附的影响因素.结果表明:(1)随Pb~(2+)平衡浓度和pH的增大,针铁矿对Pb~(2+)的吸附量逐渐增大.(2)针铁矿对Pb~(2+)的等温吸附可用Freundlich和Langmuir方程较好地拟合.(3)在相同温度和pH下,随离子强度的提高,针铁矿对Pb~(2+)的吸附量增大.(4)在相同离子强度和pH下,针铁矿对Pb~(2+)的吸附量总体随温度升高而增大.针铁矿对Pb~(2+)的吸附是自发进行的吸热反应.(5)针铁矿吸附Pb~(2+)的过程可分为初始的快吸附和随后的慢吸附2个阶段.pH影响吸附反应快慢,随pH增大吸附速率增大;随着pH的增大,达到平衡吸附的时间缩短.吸附动力学方程用Elovich方程拟合最佳. 相似文献