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641.
本文以钛白副产品绿矾为原料,氧化后,加入聚合剂生产聚合硫酸铁。  相似文献   
642.
National carbon dioxide emissions: geography matters   总被引:1,自引:1,他引:1  
Eric Neumayer 《Area》2004,36(1):33-40
This article examines the role of geographical factors as determinants of cross-country differences in per capita carbon dioxide emissions. Such differences have been explained by economists mostly in terms of per capita income. Geographical factors on the other hand have been neglected by economic analysis. We examine the effects of cold and hot climates, transportation requirements and the availability of renewable energy sources on emissions. We find that with the exception of cooling requirements as measured by hot climates, all these geographical factors are statistically significant determinants of emissions in accordance with our expectation. Furthermore, cold climates and the availability of renewable resources are also substantively important.  相似文献   
643.
There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 1935 to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93a, 108a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21st century, and then it could be becoming shorter in the second half of the 21st century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21st century is forecasted. It could warm up about 0.50℃ in the first half of the 21st century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.20℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temperature difference would likely reduce 0.3-1.00℃. The probability of above predictions ranges from 0.64 to 0.73.  相似文献   
644.
Presented here are measurements of BrO and OClO performed by ground-based UV-visible zenith-sky viewing spectrometers developed by the Norwegian Institute for Air Research (NILU). Measurements were taken at Ny-Ålesund, Spitsbergen (79° N, 11° E), in winter and spring1996 and 1997 and at Andøya (69.3° N, 16° E) from summer 1998 until summer 1999. AM and PM differential slant column densities (DSCDs) at 90°SZA of BrO and OClO reached their maxima during polar vortex conditions in the winter months and were anti-correlated to temperature andNO2. Comparison of BrO with a 3-D chemical transport model showed good agreement for seasonal trends and non-vortex conditions. BrO AM/PM ratios were underestimated by the model for vortex conditions, indicating the need for better quantification of BrO source and sink reaction rates. The detection of OClO above 200 K at the 475 K isentropic level indicates the possible activation of chlorine on sulphate particles. Several episodes of boundary layer ozone depletion due to marine-derived BrO were evident in our zenith-skyspectra during April 1997 in Ny-Ålesund.  相似文献   
645.
冷浸-氟硅酸钾法测定矿石中的二氧化硅   总被引:1,自引:0,他引:1  
陆杰芬 《矿产与地质》2002,16(5):316-317
以氢氟酸、硝酸、过氧化氢混合溶剂冷浸过夜的方式分解样品 ,然后在 3mol/ L硝酸溶液加入氯化钾生成氟硅酸钾沉淀 ,经过滤、洗涤后以沸水水解 ,所生成的氢氟酸用氢氧化钠标准溶液滴定 ,来测定二氧化硅的含量。方法操作简便 ,易于掌握。经标样验证 ,结果吻合  相似文献   
646.
论大气二氧化碳温室效应的饱和度   总被引:4,自引:0,他引:4  
利用最新版本的大气分子吸收光谱资料HITRAN2000,用精确的逐线积分算法,计算了大气CO2浓度变化后产生的辐射强迫。在此基础上,研究了CO2温室效应的饱和度以及影响CO2辐射强迫的各种因子。主要结论如下:地面温度愈高,一般辐射强迫也愈大,但辐射强迫并不完全取决于地面温度,它还受大气温度廓线的强烈影响;研究的 6种模式大气中,吸收带重叠对热带大气的CO2辐射强迫影响最大,对亚极冬季大气的影响最小;与长波辐射强迫相比,短波辐射强迫的贡献很小;CO2的温室效应在15μm带中心等波段确实已经达到饱和,但在其它(15μm带两翼,10μm,5.2μm带等)波段远未达到饱和,在最近的将来也不会达到饱和。  相似文献   
647.
The carbon isotopic ratio of atmospheric carbon dioxide at Tsukuba,Japan   总被引:1,自引:0,他引:1  
To find out the secular and seasonal trends of the 13C value and CO2 concentration in the surface air and the determination of the 13C in the atmospheric CO2 collected at Tsukuba Science City was carried out during the period from July 1981 to October 1983. The monthly average of the 13C value of CO2 in the surface air collected at 1400 LMT ranged from -7.52 to \s-8.45 with an average of -7.96±0.25 and the CO2 concentration in the air varied from 334.5 l 1-1 to 359 l 1-1 with an average of 347.2±6.3 l 1-1. The 13C value is high in summer and low in winter and is negatively correlated with the CO2 concentration. In general, the relationship between the 13C and the CO2 concentration is explainable by a simple mixing model of two different constant carbon isotopic species but the relationship does not always follow the model. The correlation between the 13C value and the CO2 concentration is low during the plant growth season and high at other times. The observed negative deviation of the 13C value from the simple mixing model in the plant growth season is partly due to the isotopic fractionation process which takes place in the land biota.  相似文献   
648.
Experiments have been performed to investigate whether the process of freezing during riming in clouds may induce oxidation of dissolved SO2 to SO 4 2– . The experiments were conducted in a cold room at varying temperatures between –6 and –15 °C. Solutions containing dissolved SO2 and NH4OH in various proportions, in the range of concentrations between 3×10–5 and 10–3 M, were sprayed. Rime was collected on a rotating cylinder and analyzed. Absorption of oxygen from laboratory air was prevented, except in the spray, to avoid spurious oxidation. Blank experiments were made at +3 to +6 °C. The results indicate clearly that, as the dominant cation becomes NH 4 + rather than H+, substantial oxidation of S(IV) occurs during riming. This is consistent with redox reactions taking place as a result of charge separation at the ice-water interface during freezing.  相似文献   
649.
朱艳芳  周志芳 《江苏地质》2001,25(4):246-250
龙滩水电站坝址区大部分平洞均存在结垢现象,且从洞口往里,碳酸钙厚度逐渐变薄。从土壤CO2对岩溶作用的驱动、土壤与外界CO2浓度的差异对碳酸钙结垢的影响出发,结合降雨资料及左岸岩体渗透张量的特征,粗略估算了强、弱微风化带内每平方米洞壁的结垢量,估算的结果与 洞壁的 实际情况相符。  相似文献   
650.
Fifty flask air samples were taken during April 1986 from a NOAA WP-3D Orion aircraft which flew missions across a broad region of the Arctic as part of the second Arctic Gas and Aerosol Sampling Program (AGASP II). The samples were subsequently analyzed for both carbon dioxide (CO2) and methane (CH4). The samples were taken in well-defined layers of Arctic haze, in the background troposphere where no haze was detected, and from near the surface to the lower stratosphere. Vertical profiles were specifically measured in the vicinity of Barrow, Alaska to enable comparisons with routine surface measurements made at the NOAA/GMCC observatory. Elevated levels of both methane and carbon dioxide were found in haze layers. For samples taken in the background troposphere we found negative vertical gradients (lower concentrations aloft) for both gases. For the entire data set (including samples collected in the haze layers) we found a strong positive correlation between the methane and carbon dioxide concentrations, with a linear regression slope of 17.5 ppb CH4/ppm CO2, a standard error of 0.6, and a correlation coefficient (r2) of 0.95. This correlation between the two gases seen in the aircraft samples was corroborated by in situ surface measurements of these gases made at the Barrow observatory during March and April 1986. We also find a similar relationship between methane and carbon dioxide measured concurrenty for a short period in the moderately polluted urban atmosphere of Boulder, Colorado. We suggest that the strong correlation between methane and carbon dioxide concentrations reflects a common source region for both, with subsequent long-range transport of the polluted air to the Arctic.  相似文献   
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