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111.
我国农业县(市)绿色食品发展对策研究 总被引:8,自引:1,他引:7
发展绿色食品是实现区域可持续发展和发展生态农业的一条有效途径。本文分析了我国农业县(市)发展绿色食品普遍存在的问题,在此基础上提出了发展绿色食品的对策。 相似文献
112.
Lawrence W. Long 《环境质量管理》1992,2(2):193-196
Anheuser-Busch is a large, diversified corporation, both in its products and in its environmental efforts. It is well-known that Anheuser-Busch is the world'S largest brewer, with twelve operating breweries and a thirteenth under construction. It also operates the largest aluminum can recycling network in the world, Anheuser-Busch Recycling (A-BR). A-BR recycled more than 600 million pounds of aluminum in 1991, or more than 17 billion cans. This article describes how Anheuser-Busch has put TQEM ideas into practice involving all of its employees. 相似文献
113.
The present research was designed to examine the psychometric properties of Chinese versions of the Self Report Driver Behavior Aggression and Assertiveness subscales, the Driving Vengeance Questionnaire, and the Violent Driving Questionnaire. Study 1 found that the all scales demonstrated good internal consistency, with alphas ranging from .76 to .87 and that assertive driving was related to demerit points received over the past 12 months while driver aggression and violence were linked to collisions over the past 12 months. Study 2 found that the scales exhibited reasonable test-retest reliability, with correlations ranging from .82 to .89. Finally, Study 3 showed that each scale was predicted by other dangerous driving attitudes and behaviors, similar to the original versions. The consistency between the translated and original scales, the implications for use in a Chinese sample, and the uniformity of actions in the traffic environment across cultures are discussed. 相似文献
114.
Quang NH Long NQ Lieu DB Mai TT Ha NT Nhan DD Hien PD 《Journal of environmental radioactivity》2004,75(3):329-337
Fallout 239+240Pu, 238Pu, 90Sr and 137Cs inventories in surface soils were measured for 20 locations in northern Vietnam yielding the mean values (+/- standard error) of 26.5+/-3.8 Bq m(-2) for 239+240Pu, 1048+/-143 Bq m(-2) for 137Cs and 212+/-28 Bq m(-2) for 90Sr. The concentrations of 137Cs and plutonium isotopes strongly correlate with each other resulting in a stable 239+240Pu/137Cs inventory ratio of 0.025+/-0.002. Among soil parameters, organic matter and fulvic acids strongly correlate with caesium and plutonium isotopes, especially in the 0-10 cm layer. 137Cs and 239+240Pu are distributed rather similarly over the 0-10 cm and 10-20 cm layers. At locations with high contents of sand (82-93%) along the South China Sea coast, the downward percolation by rainwater results in a higher accumulation of 239+240Pu and 137Cs in the 10-20 cm layer. The mean 137Cs/ 90Sr inventory ratio is 9.3+/-2.2, and the correlation is weak between these isotopes. 相似文献
115.
The rehabilitation of the former nuclear test site at Maralinga involved (among other processes) the removal of contaminated soil from an area of approximately 2.5 km2. The two most stringent rehabilitation criteria required measurements to ensure that no radioactive particle exceeding 100 kBq of 241Am activity, and no area of 1 ha exceeding 3 kBq/m2 of 241Am activity, remained in the rehabilitated area. The project timetable required that the area be scanned at the rate of approximately 3 ha/day. Two vehicle-mounted detection systems were developed and constructed to obtain the necessary measurements in the available timeframe. The scientific basis for the designs are presented, together with details of the selected equipment and technical solutions found. The performance of this equipment in the field is discussed in terms of both its scientific and technical operation. Based on the experience gained at Maralinga, improved versions of this equipment were produced under contract for the People's Republic of China. 相似文献
116.
117.
针对煤气脱硫废料(简称废料)的成分(硫、碳、萘及少量其他有机物),提出了一种处理废料的新工艺,先用乙酸乙酯提取废料中的萘和少量其他有机物,再用复合溶剂B加热溶解废料,热过滤得碳粉,最后将溶液冷却结晶分离出硫。实验结果表明:在乙酸乙酯与废料的质量比(R1)为3.75,提取温度为60℃,提取时间为4h的条件下,萘回收率为98%,纯度大于等于70%,在复合溶剂B与提取剩余物的质量比(R2)为2.69,过滤温度为100℃的条件下,硫回收率接近100%,纯度大于等于99%,碳回收率和纯度为100%。 相似文献
118.
E. Susan Boydstun Terry Nelson Roger B. Long 《Journal of the American Water Resources Association》1979,15(4):1086-1095
ABSTRACT: Public investments in water resource development projects are continually under scrutiny in terms of economic, environmental, and social impacts. Results of an analysis of a water development project that supplies irrigation water in Idaho are discussed in terms of the impact on income distribution and income growth 44 to 64 years after the project was initiated. Gini ratios for the rural farm population of these counties were consistently lower than they were for the United States as a whole and for the state of Idaho. In addition, income distributions tended to become more equitable over time in the water project counties. Rural farm population income growth rates were found to be similar to those for the nation as a whole. Some of the reasons for these results may be related to the tendency for income distribution to become more equitable as income increases, and the fact that average farm size is relatively small. 相似文献
119.
Simulation of soil loss processes based on rainfall runoff and the time factor of governance in the Jialing River Watershed,China 总被引:1,自引:0,他引:1
Jialing River is the largest tributary in the catchment area of Three Gorges Reservoir, and it is also one of the important
areas of sediment yield in the upper reaches of the Yangtze River. In recent years, significant changes of water and sediment
characteristics have taken place. The "Long Control" Project implemented since 1989 had greatly changed the surface appearance
of the Jialing River Watershed (JRW), and it had made the environments of the watershed sediment yield and sediment transport
change significantly. In this research, the Revised Universal Soil Loss Equation was selected and used to predict the annual
average amount of soil erosion for the special water and sediment environments in the JRW after the implementation of the
"Long Control" Project, and then the rainfall–runoff modulus and the time factor of governance were both considered as dynamic
factors, the dynamic sediment transport model was built for soil erosion monitoring and forecasting based on the average sediment
yield model. According to the dynamic model, the spatial and temporal distribution of soil erosion amount and sediment transport
amount of the JRW from 1990 to 2007 was simulated using geographic information system (GIS) technology and space-grid algorithm.
Simulation results showed that the average relative error of sediment transport was less than 10% except for the extreme hydrological
year. The relationship between water and sediment from 1990 to 2007 showed that sediment interception effects of the soil
and water conservation projects were obvious: the annual average sediment discharge reduced from 145.3 to 35 million tons,
the decrement of sediment amount was about 111 million tons, and decreasing amplitude was 76%; the sediment concentration
was also decreased from 2.01 to 0.578 kg/m3. These data are of great significance for the prediction and estimation of the future changing trends of sediment storage
in the Three Gorges Reservoir and the particulate non-point source pollution load carried by sediment transport from watershed
surface. 相似文献
120.
基于层次分析法的古村落旅游资源评价——以世界遗产地西递、宏村为例 总被引:1,自引:0,他引:1
以世界遗产地皖南古村落——西递、宏村为研究区域,从研究区域的资源价值和区位条件两个方面,选取了5个Ⅰ级指标:历史文化价值、科学价值、艺术价值、区域规模、交通便利程度,12个Ⅱ级指标:年代久远程度、民俗代表性、历史事件名人影响度、科学考察、科普教育、完整性、典型性、观赏性、地域组合、环境容量、通达性与服务中心距离,建立评价指标体系,并结合YAAHP软件对该指标体系进行层次分析,得出了各指标的相对权重。结果表明,西递、宏村的历史文化价值与艺术价值在其旅游资源评价中具有重要地位。在此基础上对其进行了分析并提出了相应的保护措施和对策,以期达到对西递、宏村旅游资源合理保护与开发的目的。 相似文献