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991.
A highly effective acetochlor-degrading bacterial strain (D-12) was isolated from the soil of a pesticide factory. The strain was identified as Achromobacter sp. based on its 16S rRNA gene sequence. The strain D-12 optimally degrades acetochlor at a pH of 7.0 and a temperature of 30°C in a mineral salts medium (MSM). Approximately 95% of acetochlor was degraded by the stain treated at a concentration of 10 mg L?1 after 5 days of incubation. A chiral high performance liquid chromatography (HPLC) system was used to study the enantioselectivity during the process. However, no obvious enantioselective biodegradation was observed. The primary biodegradation acetochlor products were identified by high-performance liquid chromatography-mass spectroscopy (HPLC-MS) and gas chromatography-mass spectrometry (GC-MS). The results indicated that the strain D-12 could be applied in the bioremediation of an acetochlor-polluted environment.  相似文献   
992.
The LINDE® Oxygen Combustion System has been demonstrated successfully at the EPA Denney Farm site as part of the modified EPA mobile incinerator. This paper describes the field testing results and computer modeling of the LINDE system. The oxygen system enables the EPA unit to incinerate dioxin and PCB contaminated soil at a consistent rate of 4000 lb/h—200 percent of the original maximum capacity. The pure oxygen combustion system improved the thermal efficiency of the incinerator by over 60 percent and reduced the flue gas volume dramatically. Therefore, the dust carryover problem was mitigated. The destruction and removal efficiencies of hazardous wastes exceeded EPA requirements.

The design of the proprietary burner allows the use of up to 100 percent oxygen in place of air for incineration with improvements over conventional oxy-fuel burners. As a result, the temperature distributions in the rotary kiln are uniform and NOx emissions are low.

The oxygen combustion system, controlled by a programmable controller, provided much better response and flexibility than conventional air based systems. The system generated a stable flame and responsed well to the transient conditions of the rotary kiln. Kiln puff occurrence was virtually eliminated in the operation of the mobile incinerator.

A computer model of the incinerator was developed and used for the process design of the LINDE system. The model predicted the test results reasonably well. This model can be a useful tool in the design and operation of rotary kiln incineration systems.  相似文献   
993.
合理、经济地处理混合电镀污泥,回收其中有价值的金属具有重要意义。以不同的酸作为浸出剂对电镀污泥中的金属进行了浸出效果实验。结果表明,在相同条件下,各酸的浸出效果顺序为:硫酸>盐酸>王水>硝酸;液体水与固体电镀污泥比为3,干污泥为5 g,硫酸加入量为15 mL,时间1 h条件下,混合电镀污泥中金属铜锌的浸出率最大,达到97.38%。分别采用铁和铁锰合金还原剂常温还原低熔点重金属离子铜、锌,浸出液中99%以上含量的铜、锌沉淀,使低熔点重金属与黑色金属铁、锰、铬有效分离。低熔点混合重金属可以用来做铜合金添加剂使用,最后沉淀的混合黑色金属氢氧化物处理后可以用来做炼钢合金添加剂使用。  相似文献   
994.
为了达到高效、低能耗处理分散性生活污水的目的,研制了无污泥回流和无沉淀池的流化床固定床一体化反应器。使用该反应器对模拟生活污水的处理结果表明,在水力停留时间为12 h的条件下,当进水温度为25~28℃,污染物COD、NH3-N、TN、TP和SS的浓度分别为350~450、26.4~36.9、27.0~38.5、1.7~2.6和267~345 mg/L时,相应的处理水中污染物去除率分别达到了95.7%、97.0%、51.4%、63.5%和93.9%。出水中各指标均满足《城镇污水处理厂污染物排放标准》(GB 18918-2002)中的一级排放标准。  相似文献   
995.
Time domain reflectometry (TDR) is a prospective measurement technology for moisture content of sewage sludge composting material; however, a significant dependence upon temperature has been observed. The objective of this study was to assess the impacts of temperature upon moisture content measurement and determine if TDR could be used to monitor moisture content in sewage sludge compost across a range of temperatures. We also investigated the combined effects of temperature and conductivity on moisture content measurement. The results revealed that the moisture content of composting material could be determined by TDR using coated probes, even when the measured material had a moisture content of 0.581 cm3 cm?3, temperature of 70 °C and conductivity of 4.32 mS cm?1. TDR probes were calibrated as a function of dielectric properties that included temperature effects. When the bulk temperature varied from 20 °C to 70 °C, composting material with 0.10–0.70 cm3 cm?3 moisture content could be measured by TDR using coated probes, and calibrations based on different temperatures minimized the errors.  相似文献   
996.
EGSB—MBBR处理高浓度聚酯废水   总被引:1,自引:0,他引:1  
采用膨胀床颗粒污泥反应器(EGSB)—移动床生物膜反应器(MBBR)处理高浓度、难降解(COD≥10000mg/L,BOD5/COD0.3)聚酯废水。实验结果表明:在(37±1)℃、停留时间(HRT)为15.4h、进水COD为10000mg/L的条件下,EGSB反应器容积负荷达5.31kg/(m3.d),COD去除率达95%以上;在室温、HRT为48.0h的条件下,MBBR反应器出水COD100mg/L,BOD530mg/L,出水水质达到GB8978—1996《污水综合排放标准》中的一级排放标准。  相似文献   
997.
Fe(Ⅲ)-酒石酸盐配合物对双酚A模拟废水的光处理   总被引:2,自引:1,他引:1  
主要研究了卤灯光照下,Fe(Ⅲ)-酒石酸盐配合物体系对双酚A(BPA)的光化学降解,考查了光源、初始pH值、各反应物初始浓度等因素对双酚A光降解的影响。结果表明:卤灯或太阳光照射下,BPA在Fe(Ⅲ)-酒石酸盐配合物体系中能够有效地实现光降解;光强从8.8×104Lux增加到1.2×105Lux,BPA降解率从68.9%提高到92.8%;BPA的降解率及Fe(Ⅲ)-酒石酸盐配合物光解过程中产生的.OH浓度均随pH增大而减小;Fe(Ⅲ)-酒石酸盐配合物光氧化BPA过程中溶液的pH逐渐升高;过量的酒石酸盐有利于Fe(Ⅲ)/Fe(Ⅱ)的循环进行。  相似文献   
998.
This study uses an input–output model presenting the embodied carbon emission in the import–export procedure, as well as the responsibility allocation between China’s 35 sectors and 7 main trade partners from 1995 to 2011. Results indicate that the amount of carbon emissions in China’s industrial sectors is immense and that the industrial sectors are in serious imbalance. Such imbalance exists mainly in textiles, basic and fabricated metal, electrical and optical equipment, and machinery, among others. Based on the consumer-responsibility principle, the responsibility of 29 departments is reduced. Correspondingly, foreign sectors become more responsible. America, as China’s largest trading partner, should account for most of the total responsibility, followed by developed countries such as Japan, South Korea, and Germany.  相似文献   
999.
以TiSO4和尿素为主要原料,EDTA为控制剂,采用微波水热法制备纳米TiO2光催化剂,并分析了纳米TiO2晶粒的最佳形成条件。利用XRD、TEM等技术对制备产物进行表征。结果表明,TiSO4和尿素混合物在微波水热条件下晶化150 min后,产物为锐钛矿型TiO2,且产物粒径小、大小均匀。在紫外光照射下,以自制的锐钛矿型纳米TiO2为催化剂,酸性橙为降解目标物,进一步研究了其光催化性能。结果表明,该TiO2在紫外光照射下表现出稳定的光催化活性。  相似文献   
1000.
Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced.  相似文献   
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