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BD2F钢亚温气体碳氮共渗和淬火工艺研究与应用
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作者 杨以凡 孟毅华 《安徽工学院学报》 1986年第3期64-75,共12页
本文介绍了 BD2F 钢采用甲醇添加三乙醇胺为共渗剂,于780~820C 进行亚温气体碳氮共渗和淬火,获得0.5毫米渗层深度,HRA82致密的碳氮马体层。该工艺特点,是基体只发生部分相变,因而变形极小。本文从测定不同工艺的碳氮浓度分布、组织结... 本文介绍了 BD2F 钢采用甲醇添加三乙醇胺为共渗剂,于780~820C 进行亚温气体碳氮共渗和淬火,获得0.5毫米渗层深度,HRA82致密的碳氮马体层。该工艺特点,是基体只发生部分相变,因而变形极小。本文从测定不同工艺的碳氮浓度分布、组织结构、显微硬度分布、机械性能和变形试验情况与液体氰化相比较。试验结果表明、该工艺完全能够取代液体氰化,消除公害,适合处理轻纺工业上薄小形状复杂零件,经济效果显著。 展开更多
关键词 甲醇 三乙醇胺 亚温气体碳氮共渗 液体氰化 机械性能
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亚温气体薄层渗碳方法初探
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作者 李培泽 《机械工人(热加工)》 1996年第2期17-17,共1页
通常把渗碳层深度小于0.50mm的渗碳工艺称为薄层渗碳,而常见的薄层渗碳是把渗碳层深度控制在0.20~0.50mm之间。如果要把渗碳层深控制在0.20mm以下,而工件表面的碳浓度又要达到共析点以上,一般要借助于高级的设备,如,真空渗碳。
关键词 亚温气体 薄层渗碳 化学热处理
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New Method for Desalination of Seawater 被引量:1
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作者 Guyteau Bayard 《Journal of Chemistry and Chemical Engineering》 2013年第9期892-896,共5页
The present study explores the possibility of appealing to the laws of inorganic chemistry, i.e., the rules of precipitation to desalinate seawater. Historically, the industry has been using these techniques for the p... The present study explores the possibility of appealing to the laws of inorganic chemistry, i.e., the rules of precipitation to desalinate seawater. Historically, the industry has been using these techniques for the preparation of some compounds. Based on these rules, using suitable salts will react with each other. The results are evident all unwanted salts including sodium chloride are removed. In fact, it is a selective precipitation as other salts which are not harmful are kept such as potassium. The other aim of the study is to reduce the current ratio desalination/power which is very high 60,000 to 80,000 cal/L for distillation (A. Payant. P. Chiliotti L. Sainte-Marie Physic Arm and Colin, Paris, France) or 4.5 kWh/m3 for RO (desalination and water reuse, California, USA) a cause of greenhouse gas except desalination using solar energy. Another aspect of this study, authors noticed rather than consume energy, regeneration or recycling of products provides energy. And in addition, the operation does not cause any pollution. 展开更多
关键词 WATER ENERGY potassium.
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The Impact of Climate Change on Sustainable Food Supply and Environmental Safety in Ekiti State, Nigeria
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作者 Joseph Adunbi Ogundele 《Journal of Agricultural Science and Technology(A)》 2014年第4期323-330,共8页
The resultant climate change on sustainable food supply has greatly affected agricultural production by the level of great volumes of gasses emitted into the atmosphere by human activities. The human factors that emit... The resultant climate change on sustainable food supply has greatly affected agricultural production by the level of great volumes of gasses emitted into the atmosphere by human activities. The human factors that emit large amount of green house gases include industrialization, burning of fossil fuel and gas flaring. Increase in air temperature and consequent increase in the rates of evaporation also affect the level of food supply. Data for this study were collected from primary and secondary sources. Primary source were collected through field investigation and structured questionnaire. A total of 450 questionnaires were administered. Results revealed that varieties of crops ranging from tree crops to cereals were cultivated within the study area. The effect of climate change on food supply has resulted into change in crop yields, change in rainfall pattern, soil loss and has greatly affected planting period and harvesting. The study therefore recommended awareness campaigns on the causes and consequences of global climate change on food production, environmental education and afforestation campaign programmes on sustainable food supply and environmental safety must be intensified. 展开更多
关键词 Sustainable food supply green house gases environmental campaign.
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A Comparative Analysis of Emission of Methane from Livestock Farms in Enugu, Eastern Nigeria
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作者 N. B. Ac-Chukwuocha D. H. Ogbuagu V. O. Okoro 《Journal of Agricultural Science and Technology(A)》 2011年第6期908-912,共5页
This study compares CH4 emissions from different livestock farms (poultry, cattle and swine farms) in Enugu, Eastern Nigeria. Data on animal type, number and age were obtained by direct observations while the concen... This study compares CH4 emissions from different livestock farms (poultry, cattle and swine farms) in Enugu, Eastern Nigeria. Data on animal type, number and age were obtained by direct observations while the concentrations of CH4 in the livestock farms were measured with the Gasman Crowcrown Gas Monitor. Daily ambient air temperature and rainfall data were obtained from the Nigerian Meteorological Agency (NIMET) Enugu. Regression analysis was used to determine possible relationships existing between weather parameters and CH4 emissions while the One-Way ANOVA was used to determine variance equality in means of greenhouse gas emission spatially at P 〈 0.05. Minimum and maximum temperatures ranged between 21.9 and 22.7 ℃ and 26.2 and 30.6 ℃ respectively, with rainfall ranging between 0.0 and 12.5 mm during the study period. Of the livestock farms sampled, swine farm emitted the highest concentrations of the greenhouse gas at both the livestock house (2.88 ± 0.28 ppm) and feaces decomposition site (2.30 ±0.30 ppm), while poultry emitted the least concentrations of 1.96 ± 0.23 and 1.92 ± 0.10 ppm in the livestock house and faeces decomposition locations respectively. Age and number of livestock did not affect emissions of greenhouse gas. Though the prevailing weather parameters measured (temperature and rainfall) did not exert significant influences on greenhouse gas emissions, significant spatial variations in emissions in the feaces decomposition sites of the farmhouses was observed at P 〈 0.05. CH4emission in cattle farmhouse (2.80 ± 0.46 ppm) and swine farmhouse (2.88 ± 0.28 ppm) as well as those measured in the faeces decomposition locations of swine farmhouse (2.30 ± 0.30 ppm) exceeded the CH4 concentration level of 2.0 ppm measured in dry air at sea level. There is need for a further research on the effects of animal age, growth rate and biochemistry on CH4 emissions at the farmhouses. 展开更多
关键词 Greenhouse effects METHANE ENUGU EMISSIONS livestock farms.
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Development of Biomass Utilization in Latvia
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作者 Peteris Shipkovs Galina Kashkarova +1 位作者 Kristina Lebedeva Lana Migla 《Journal of Energy and Power Engineering》 2013年第1期96-101,共6页
This paper describes an efficient and appropriate use of biomass in Latvian conditions as well as analyzing the current situation, leading to recommendations for rational use of biomass and the full implementation of ... This paper describes an efficient and appropriate use of biomass in Latvian conditions as well as analyzing the current situation, leading to recommendations for rational use of biomass and the full implementation of the Latvian energy sector. In recent year's, Latvian energy sector development analysis shows, that there is a positive tendency--an increase of local and renewable energy share of energy balance. The paper will be identified for future development opporttmities, and will undertake an analysis of renewable energy consumption forecasting in accordance with the renewable energy potential assessment, taking into account the effective use of innovative technologies and ecological aspects of the energy sector. Increasing use of biomass for district heating (and cogeneration), also increase the efficient use ofbiomass in cost efficiency and reducing of GHG emissions. Efficient use of biomass analyzed in the paper, taking into account technical, legislative, institutional/organizational, economic, information and financial aspects. Promoting of the efficient use of biomass will increase national energy independence. 展开更多
关键词 BIOMASS energy balance COGENERATION district heating biomass utilization.
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Numerical simulation study of temperature change over East China in the past millennium 被引量:6
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作者 XIAO Dong ZHOU XiuJi ZHAO Ping 《Science China Earth Sciences》 SCIE EI CAS 2012年第9期1504-1517,共14页
Despite many studies on reconstructing the climate changes over the last millennium in China,the cause of the China's climate change remains unclear.We used the UVic Earth System Climate Model(UVic Model),an Earth... Despite many studies on reconstructing the climate changes over the last millennium in China,the cause of the China's climate change remains unclear.We used the UVic Earth System Climate Model(UVic Model),an Earth system model of intermediate complexity,to investigate the contributions of climate forcings(e.g.solar insolation variability,anomalous volcanic aerosols,greenhouse gas,solar orbital change,land cover changes,and anthropogenic sulfate aerosols) to surface air temperature over East China in the past millennium.The simulation of the UVic Model could reproduce the three main characteristic periods(e.g.the Medieval Warm Period(MWP),the Little Ice Age(LIA),and the 20th Century Warming Period(20CWP)) of the northern hemisphere and East China,which were consistent with the corresponding reconstructed air temperatures at century scales.The simulation result reflected that the air temperature anomalies of East China were larger than those of the global air temperature during the MWP and the first half of 20CWP and were lower than those during the LIA.The surface air temperature of East China over the past millennium has been divided into three periods in the MWP,four in the LIA,and one in the 20CWP.The MWP of East China was caused primarily by solar insolation and secondarily by volcanic aerosols.The variation of the LIA was dominated by the individual sizes of the contribution of solar insolation variability,greenhouse gas,and volcano aerosols.Greenhouse gas and volcano aerosols were the main forcings of the third and fourth periods of the LIA,respectively.We examined the nonlinear responses among the natural and anthropogenic forcings in terms of surface air temperature over East China.The nonlinear responses between the solar orbit change and anomalous volcano aerosols and those between the greenhouse gases and land cover change(or anthropogenic sulfate aerosols) all contributed approximately 0.2℃ by the end of 20th century.However,the output of the energy-moisture balance atmospheric model from UVic showed no obvious nonlinear responses between anthropogenic and natural forcings.The nonlinear responses among all the climate forcings(both anthropogenic and natural forcings) contributed to a temperature increase of approximately 0.27℃ at the end of the 20th century,accounting for approximately half of the warming during this period;the remainder was due to the climate forcings themselves. 展开更多
关键词 past millennium East China climate forcings UVic Model nonlinear response
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