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991.
A. G. Tumanovskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2005,39(2):95-103
The main legislative documents in the field of environmental protection and ecological standards for newly developed equipment of thermal power plants (TTP) of Russia are presented. Problems of raising the efficiency TTP and reducing harmful emissions are considered. Modern methods and process for lowering nitrogen oxide emissions for different kinds of fuel, fields of application of sulfur-removing technologies, and ways for updating fly-ash collectors are discussed. The tendency to tightening of standards regulating the volume of contaminating substances is shown. Data on TTP wastewaters and maximum permissible concentrations (MPC) of primary contaminants are presented. Reduction of atmospheric emissions and of contaminating due TTP wastewaters is estimated until 2010.__________Translated from Elektricheskie Stantsii, No. 1, January 2005, pp. 17–27 相似文献
992.
Soil nutrient deficiency has hampered increased agricultural production in the savannas of northern Nigeria. It has been observed that inorganic fertilizer (IF) has the potential to reverse the situation. However, low adoption among the farmers has characterized IF in the savannas of northern Nigeria. The application rates have also fallen far lower than the rate recommended by research and extension, resulting in low crop yields. This paper investigates the factors that influence farmers' decision to adopt or not to adopt IF and to evaluate the elasticity of adoption. This information will help to prioritize the factors that affect IF adoption decisions and suggest pathways for effective promotion of IF. About 49% of the survey farmers adopted IF and the application rate ranges from 5.6 to 64.4 kg ha–1 (with a mean of 24.1 kg ha–1). The probability of adoption increases with increased targeting of: farmers from the Guinea savanna agroecological zone, younger farmers, better educated farmers, food secure farmers and net sellers of food grains, farmers who have diversified into many crops, farmers who perceive increase in the fertilizer needs of their crops, and farmers who apply large quantities of organic manure. Among others, the estimates of elasticity of adoption indicate that a 1% increase in the number of farmers who perceive an increase in the fertilizer needs of their crops results in 3.23% increase in the probability of IF adoption. The paper concludes with policy implications for strategies aimed at promoting IF in the savannas of Nigeria and similar ecologies elsewhere. 相似文献
993.
泥炭绿色环保肥料的发展与创新 总被引:2,自引:2,他引:0
泥炭具有特殊的物理、化学和生物学特性,在绿色环保肥料制备和绿色、有机食品生产中的潜在价值巨大。文章论述了泥炭在绿色环保肥料中的应用价值,介绍了国内外泥炭绿色环保肥料的发展趋势。根据作者的泥炭高技术产品开发经验,对泥炭绿色环保肥料的研制创新方法提出了建议。 相似文献
994.
高选择性脱除润滑油基础油中碱性氮化物 提高润滑油基础油的氧化安定性 总被引:6,自引:1,他引:5
采用武汉石油化工厂开发的WSQ-2脱氮剂专利技术能高选择性脱除润滑油基础油中碱性氮化物,脱碱氮率能达90%以上,而硫化物的脱除率则很低。脱氮后基础油理化性质基本不变,而氧化安定性则有显著的提高。大庆石蜡基基础油脱碱氮后的旋转氧弹可达200min以上,南阳中间基基础油脱氮后的旋转氧弹可达250min左右。 相似文献
995.
针对聚酯生产用氮偏大的现状,分析了造成氮耗大的原因,对氮封装置氮气用量进行了工艺改进;在PTA卸料外氮管线安装了节流孔板,从而降低了氮气消耗,节约了生产成本。 相似文献
996.
W. Hemminger 《International Journal of Thermophysics》1987,8(3):317-333
Air desorbed from the measuring instrument can falsify the thermal conductivity of a gas measured by steady-state methods. For a guarded hot-plate apparatus the contamination effect was determined to depend on both the residence time in the system and the temperature. The investigation covered the gases H2, He, Ne, CH4, N2, air, Ar, and Kr. For gases whose conductivity is better than that of air (H2, He) the measured values are too small, and for gases of poorer conductivity they are too high. Corrections for the effect of impurity have been applied to the measurements presented. These impurity corrections are considerably larger than the precision of the measurements, but they are of the order of the estimated overall uncertainty of the measurements. The departures between the corrected thermal conductivities reported here and values taken from the correlations in the literature run up to 5 % at the highest temperatures. 相似文献
997.
This paper presents two schemes for a theoretically based data assessment of the thermal conductivity of dilute polyatomic gases. The first employs the simplified Thijsse expression, combined with accurate experimental data obtained from a transient hot-wire apparatus, as reference. The second makes use of theoretical results for the temperature dependence of the ratio D
int/D. Both methods lead to mutually consistent results for linear molecules and to useful criteria for discriminating between experimental data sets. The paper also demonstrates the influence of data burdened with systematic errors upon the final results of different correlation schemes. 相似文献
998.
硝酸钾既是重要的工业原料,又是优质无氯钾、氮复合肥料,植物营养素钾、氮的总质量分数可达60%左右,是发展现代高效农业不可缺少的化肥品种。由于生产、市场、价格等方面的原因,目前硝酸钾在中国施用较少,而这种称为世界紧缺的"绿色钾肥"在欧洲国家较为盛行。伴随着高科技农业的不断发展,以及人们对食品安全要求的不断提高,中国市场对硝酸钾的需求将不断增加,不过目前这一市场仍表现出过于狭窄。简要介绍了硝酸钾的生产技术、中国硝酸钾生产发展现状、硝酸钾应用领域及市场前景,并对硝酸钾的发展提出了一些建议。 相似文献
999.
Establishment of an agronomic database for Minjingu phosphate rock and examples of its potential use
A compilation of all presently available agronomic data on the Tanzanian Minjingu phosphate rock (MPR) has shown to be a valuable
tool for evaluating the interactions between tropical soils and MPR or water-soluble P sources (WSP). The effect of a delayed
dissolution of MPR products compared to WSP was clearly demonstrated by the slope of the regression curve relating the yield
response to MPR with the yield response to WSP. In the first 2 years, the average effectiveness of MPR is 74 and 94% of WSP
respectively, whereas from the third year onwards the relative effectiveness is around 104%. From the analysis of the effect
of soil properties on the yield response, it was found that low soil pH and low amounts of available P are the most favourable
conditions for the effective use of MPR. However, beneficial effects were also indicated on less acidic soils if they are
strongly P deficient. MPR application seems to have superior effect on soil properties such as pH, exchangeable Ca and Al
compared with WSP. The effect of MPR application on available P and NaOH extractable P is significantly lower compared with
WSP but the difference seems relatively small. An estimation of the distribution of the cultivated area of Tanzania into four
suitability classes for direct application of MPR seems to be a useful tool in the process of selecting target areas where
direct MPR application should be promoted. 相似文献
1000.
对矸石山的风化物施用化肥或生活污泥,进行种植苏丹草、红豆草的盆栽试验。试验结果:生活污泥对生物量的提高可达极显著水平,当施用60t/hm2污泥种植苏丹草时,比只施磷钾肥干物质量增加332%;当施用30t/hm2污泥种植红豆草,比不施肥增加1519%。 相似文献