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181.
Jürgen Bennewitz 《Environment, Development and Sustainability》2009,11(1):127-136
The IPCC Working Groups I–III 2007 publications does not consider the question of the influence of the entropy increase in
the atmosphere on current climate development. An investigation into this question, both in general terms as well as by two
quantitative approaches, reveals we must consider the entropy produced by man in connection with climate development, especially
with regard to the temperature increase of the atmosphere. The IPCC report also fails to mention the production of CO2 by humans and livestock, but calculations show we must also consider such greenhouse gas CO2 production. For solving the mitigating processes, we therefore have to take into account both the human induced entropy production
and the direct human and livestock CO2 output. In consideration of these findings, it seems necessary to introduce an “entropy identity” to people who wish to be
able to continue to live on the planet. The introduction of an entropy tax might also help in solving the most urgent fundamental
problem humanity has ever had to face.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
182.
研究了温度、酸碱度对重组杆状病毒(AcMNPV-BmKIT-Chi)毒力的影响.结果显示,多角体病毒在温度4~50℃,pH6.0~8.0范围内可以保持较高的毒力稳定性;不同虫龄棉铃虫幼虫对重组病毒的毒力敏感性差异显著,低虫龄对重组核型多角体病毒更为敏感;病毒对幼虫存在亚致死作用,饲毒组与对照组幼虫体重差异显著.图3表3参13 相似文献
183.
Temperature and relative humidity distributions in a medium-size administrative town in southwest Nigeria 总被引:5,自引:0,他引:5
This study was carried out in one of the medium-sized public administrative towns in the southwestern part of Nigeria. Its aim is to highlight the effect of spatial distribution of settlements, population, and socio-economic activities on urban air temperature and humidity in the town. Temperature and relative humidity data from 1992 to 2001 were obtained from three meteorological stations in Akure, the Administrative Capital of Ondo State, Nigeria. The stations are located within the Federal Ministry of Aviation, Akure Airport (FMA), Federal University of Technology, Akure (FUTA) and Federal School of Agriculture (SOA). Air temperature and relative humidity measurements were also obtained from 27 points, which were cited to include road junctions, markets, built up areas, etc., using sling psychrometer. The data were subsequently analysed for spatial and temporal variations using statistical packages (SPSS and Microsoft Excel) and isolines. Actual vapour pressure and dew point temperature were computed using Magnus conversion formulae. The results obtained showed that spatial variation was insignificant, in terms of the temperature and humidity variables. The annual mean temperature (Tmean) ranged between 21.9 and 30.4 degrees C while minimum (Tmin) and maximum (Tmax) temperatures varied from 13 to 26 and 21.5-39.6 degrees C, respectively. Relative humidity (RH), actual vapour pressure (Es) and dew point temperature (Td) values also varied from 39.1% to 98.2%, 19.7-20.8 gm(-3), and 17.3-17.8 degrees C, respectively. A significant relationship (p>0.6; r<0.05) between Tmin, Es and Td was observed while the daytime 'urban heat island' intensity (UHI) ranged between 0.5 and 2.5 degrees C within the study period. The study concluded that there is influence of urban canopy on the microclimate of Akure, and hypothesizes that the urban dwellers may be subjected to some levels of weather related physiological disorderliness. 相似文献
184.
The present study centered on the composition of landfill gas and its effects on soil and plants at the Gin Drinkers' Bay (GDB) landfill in Hong Kong This first part of the study was a whole-year monitoring of landfill gas composition in the gas ventilation system installed on top of the landfill Methane, carbon dioxide, oxygen, and ethylene were measured It was shown that gas generation was positively correlated with the amount of precipitation and air temperature and negatively correlated with atmospheric pressure 相似文献
185.
186.
研究钢筋混凝土柱在升温、降温加热曲线作用下的截面温度场分布。完成了1根边长700mm方形钢筋混凝土柱的四面受火温度场试验,加热曲线升温段为ISO-834标准升温曲线,降温段为随炉冷却降温曲线。试验过程中测得了柱截面内不同位置的温度变化。建立有限元模型对试验结果进行了模拟分析。结果表明:方形柱截面内不同位置的升温速率、降温速率受其距受火面距离影响较大;截面内距离受火面越远的位置,升温滞后现象越明显;在ISO-834标准升温和随炉降温加热曲线作用下,当方形柱的截面边长大于等于700mm时,柱截面内的温度分布可反映大截面尺寸钢筋混凝土柱在火灾升、降温阶段的温度分布变化。 相似文献
187.
A couple of experiments were conducted to estimate the optimal temperature effect on growth of Chinese shrimp (Penaeus chinensis). The equation describing growth-temperature relationship derived from the first experiment with temperature ranging from 16° to 31°C was found linear as the following: ,where G and T are daily growth rate and temperature, respectively.The second experiment indicated that the daily growth rate was a quadratic function of temperature at the limits of 27° and 35°C. The equation was .The optimal temperature in terms of maximum growth was 31.26°C. 相似文献
G = -0.005667 + 0.001103 T
G = -0.339587 + 0.023476 T − 0.000375 T2
188.
立井井壁破坏应力研究 总被引:2,自引:0,他引:2
吴怀俊 《中国安全科学学报》2003,13(7):21-24
应用利用弹性理论、温度应力场理论、热胀冷缩原理 ,对立井井壁破坏应力进行了较为精确的受力分析 ,给出了立井井壁应力分布规律的解析式。在整个理论的分析过程中 ,笔者着重分析了井壁应力中负摩擦力的影响 ,对负摩擦力引起的井壁应力进行了较为细致的计算 ,并通过具体算例进行了说明。笔者研究的结果 ,为井壁设计的理论提供了新的依据 ,同时对煤矿设计及煤矿工程应用有重要实用价值。 相似文献
189.
190.
We estimated the effects of a temperature control device (TCD) on a suite of thermodynamic and limnological attributes for
a large storage reservoir, Shasta Lake, in northern California. Shasta Dam was constructed in 1945 with a fixed-elevation
penstock. The TCD was installed in 1997 to improve downstream temperatures for endangered salmonids by releasing epilimnetic
waters in the winter/spring and hypolimnetic waters in the summer/fall. We calibrated a two-dimensional hydrodynamic reservoir
water quality model, CE-QUAL-W2, and applied a structured design-of-experiment simulation procedure to predict the principal
limnological effects of the TCD under a variety of environmental scenarios. Calibration goodness-of-fit ranged from good to
poor depending on the constituent simulated, with an R
2 of 0.9 for water temperature but 0.3 for phytoplankton. Although the chemical and thermal characteristics of the discharge
changed markedly, the reservoir's characteristics remained relatively unchanged. Simulations showed the TCD causing an earlier
onset and shorter duration of summer stratification, but no dramatic affect on Shasta's nutrient composition. Peak in-reservoir
phytoplankton production may begin earlier and be stronger in the fall with the TCD, while outfall phytoplankton concentrations
may be much greater in the spring. Many model predictions differed from our a priori expectations that had been shaped by an intensive, but limited-duration, data collection effort. Hydrologic and meteorological
variables, most notably reservoir carryover storage at the beginning of the calendar year, influenced model predictions much
more strongly than the TCD. Model results indicate that greater control over reservoir limnology and release quality may be
gained by carefully managing reservoir volume through the year than with the TCD alone. RID=" ID=" Author to whom correspondence
should be addressed. e-mail: John_Bartholow@USGS.gov 相似文献