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91.
文章通过对火电项目煤尘产生源的分析,根据北方地区社会、经济、环境现状,提出电厂储煤场及输煤系统煤尘的主要防治措施,从而为北方经济欠发达地区火电厂的煤尘污染防治提供一些参考依据,促进环境质量的改善。  相似文献   
92.
煤矸石的环境问题及其资源化利用   总被引:34,自引:0,他引:34       下载免费PDF全文
煤矸石是煤炭生产中的一种副产品,目前煤矿的排矸量约占煤炭开采量的10%~25%,煤矸石已成为我国累积堆积量和占用场地最多的工业废物。文中介绍了国内外煤矸石综合利用现状及工程利用的主要领域,并就如何提高我国煤矸石工程利用水平提出作者的观点。   相似文献   
93.
In this study, a high-efficiency cationic flocculant, P(DAC-MAPTAC-AM), was successfully prepared using UV-induced polymerization technology. The monomer Acrylamide (AM): Acryloxyethyl Trimethyl ammonium chloride (DAC): methacrylamido propyl trimethyl ammonium chloride (MAPTAC) ratio, monomer concentration, photoinitiator concentration, urea content, and cationic monomer DAC:MAPTAC ratio, light time, and power of high-pressure mercury lamp were studied. The characteristic groups, characteristic diffraction peaks, and characteristic proton peaks of P(DAC-MAPTAC-AM) were confirmed by fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), 1H nuclear magnetic resonance spectrometer (1H NMR), and scanning electron microscopy (SEM). The effects of dosage, pH value, and velocity gradient (G) value on the removal efficiencies of turbidity, COD, ammonia nitrogen, and total phenol by poly aluminum ferric chloride (PAFC), P(DAC-MAPTAC-AM), and PAFC/P(DAC-MAPTAC-AM) in the flocculation treatment of coal chemical wastewater were investigated. Results showed that the optimal conditions for the flocculation of coal chemical wastewater using P(DAC-MAPTAC-AM) alone are as follows: dosage of 8–12 mg/L, G value of 100–250 s ? 1, and pH value of 4–8. The optimal dosage of PAFC is 90–150 mg/L with a pH of 2–12. The optimal dosage for PAFC/P(DAC-MAPTAC-AM) is as follows: PAFC dosage of 90–150 mg/L, P(DAC-MAPTAC-AM) dosage of 8–12 mg/L, and pH range of 2–6. When P(DAC-MAPTAC-AM) was used alone, the optimal removal efficiencies of turbidity, COD, ammonia nitrogen, and total phenol were 81.0%, 35.0%, 75.0%, and 80.3%, respectively. PAFC has good tolerance to wastewater pH and good pH buffering. Thus, the flocculation treatment of coal chemical wastewater using the PAFC/P(DAC-MAPTAC-AM) compound also exhibits excellent resistance and buffering capacity.  相似文献   
94.
离子选择性电极测定煤中氟浓度方法及影响因素分析   总被引:3,自引:0,他引:3  
采用高温碱熔离子选择性电极法测量烟煤及石煤中氟化物浓度,对测量过程中的影响因素进行了分析,并对溶液的pH值及温度的影响进行了试验研究,结果表明该测量方法准确度较高,误差小,测量方便快速,实用性强,可作为煤及其它矿物质中氟含量测量的一种有效方法  相似文献   
95.
三峡库区燃煤,土壤和水库底泥中含汞量分布特征   总被引:6,自引:0,他引:6  
详细研究了长江三峡库区燃煤,土壤和沉积物中汞的分布特征,以及湖泊沉积物中不同形态汞的含量,探讨了水库汞污染加重原因。  相似文献   
96.
The total annual production of coal combustion by-products in the USA is expected to exceed 150 million Mg by the year 2000. Agricultural utilisation may offer a partial solution to disposal problems, but the benefits and risks associated with using these materials must be assessed. Four coal combustion by-products, bed ash (BA) and fly ash (FA) from a fluidised-bed combustion furnace and stabilised scrubber sludge (SS) and a high gypsum content by-product (G) from flue gas desulphurisation processes were added to two soils at rates of 0, 20, 40 and 80 g kg-1. The growth and elemental composition of Gulf annual ryegrass (Lolium multiflorum L.) were evaluated in the treated soils. Adding FA, SS and G to both soils at application rates of up to 80 g kg-1 was not detrimental to the growth of ryegrass and resulted in higher yields than controls in some instances. Adding BA created a high alkalinity, high soluble-salt environment that initially inhibited seedling germination and significantly reduced (p<0.05) yields of dry matter, so it will probably need to be restricted to rates of lime requirement. Ryegrass concentrations of Cu, Zn, Ni, Pb, Cd and Cr were similar in control and treated soils, but levels of B, Se, As and Mo were raised in treatments. Based on low trace-element concentrations in ryegrass shoots and in soil solution, Se from FA application may be the only potential food-chain risk associated with application of the four coal combustion by-products used in this investigation.  相似文献   
97.
装饰材料所致的室内空气污染   总被引:25,自引:0,他引:25  
对商业、工业、住宅等不同功能区和不同室内燃料的厨房、卧室、教室等室内房间,作了空气中甲醛的本底值调查。调查表明,甲醛浓度范围为0.0007-0.0125mg/m^3。对15户普通家庭装潢户的调查表明,经装潢后1年以上测得的甲醛,总烃、苯、甲苯平均浓度分别为0.02、0.50、0.76、1.25mg/m^3。氯乙烯、苯乙烯未测出。其中甲醛平均浓度高出本底值20倍,为前苏联建议的日平均浓度的1.6倍。  相似文献   
98.
粉煤灰的有效利用   总被引:6,自引:0,他引:6  
介绍了我国粉煤灰利用状况及政策,结合实例分析了粉煤灰的有效利用和清洁生产对促进粉煤灰有效利用的作用。  相似文献   
99.
本文通过对兖州矿区大气污染源的调查,分析了矿区煤烟型污染的治理现状、控制技术和效果及存在的问题。结合矿区实际,对煤烟型污染的治理和控制技术的优化作了探讨。  相似文献   
100.
China's energy dependents on coal due to the abundance and low cost of coal. Coal provides a secure and stable energy source in China. Over-dependence on coal results in the emission of Hazardous Trace Elements (HTEs) including selenium (Se), mercury (Hg), lead (Pb), arsenic (As), etc., from Coal-Fired Power Plants (CFPPs), which are the major toxic air pollutants causing widespread concern. For this reason, it is essential to provide a succinct analysis of the main HTEs emission control techniques while concurrently identifying the research prospects framework and specifying future research directions. The study herein reviews various techniques applied in China for the selected HTEs emission control, including the technical, institutional, policy, and regulatory aspects. The specific areas covered in this study include health effects, future coal production and consumption, the current situation of HTEs in Chinese coal, the chemistry of selected HTEs, control techniques, policies, and action plans safeguarding the emission control. The review emphasizes the fact that China must establish and promote efficient and clean ways to utilize coal in order to realize sustainable development. The principal conclusion is that cleaning coal technologies and fuel substitution should be great potential HTEs control technologies in China. Future research should focus on the simultaneous removal of HTEs, PM, SOx, and NOx in the complex flue gas.  相似文献   
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