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151.
152.
采用大涡PIV方法对Taylor-Couette流场的湍动能及湍动能耗散率进行了估算,并利用数值模拟对其进行验证,结合絮凝实验,综合对比速度矢量、湍动能分布、湍动能耗散率分布及对应流场中混凝过程的絮体图像,探究了湍动能与湍动能耗散率对絮凝效能的影响.结果表明,大涡PIV法与数值模拟在雷诺数较高的情况下有较好的一致性,且雷诺数越大一致性越好.在Taylor-Couette涡流场中,随着雷诺数的增大,湍动能与湍动能耗散率数值不断增大,且在流场中的分布由规律有序到紊乱最终趋于各向均匀一致.而混凝过程中湍动能与湍动能耗散率的数值大小及其在流场中的空间分布情况,均对产生絮体的大小和浊度去除率有较大影响. 相似文献
153.
This study examines the Granger causality relationships between economic growth, energy consumption and emissions, from 1980 to 2007 in Bahrain, controlling for capital and urban population using Toda and Yamamoto’s approach. It was found that there is unilateral causality which runs from urban population, economic growth, capital and energy consumption to environment. Further, we found strong support for causality running from economic growth to energy consumption, emissions and capital. The existence of these linkages suggests that the government of Bahrain may pursue energy efficiency strategies and carbon emissions reduction policy in the long run without impeding economic growth. Additionally, the long run pursuit of high economic growth given sustained increases in energy efficiency may also reduce CO2 emissions intensity per unit of her GDP. 相似文献
154.
改革开放以来中国能源效率不断地提高,但是在某些年份存在波动现象.采用非线性分形理论及分形分析R/S方法,科学定量地描述了中国以及各个地区能源效率的演变趋势.首先采用分形理论对1978-2008年的中国能源效率时间序列数据进行研究,结果显示,中国能源效率发展演变存在Hurst现象,具有明显的分形特征.并依照“五年计划”来划分时间序列样本为研究区间,结合“五年计划”详尽地解释说明了中国能源效率变动的原因.然后将数据扩大为样本期为1995-2008年29地区的面板数据,采用面板变系数模型进一步对各个地区的能源效率进行分析,发现除海南外其他地区的能源效率演变过程中具有明显的持续性规律,各个地区能源效率将继续保持增长.西部6个地区以及东北三省的能源效率演变趋势高于全国水平,说明“西部大开发”战略和“振兴东北”战略都已经显效. 相似文献
155.
Either from the perspective of the finite supply capacity of global resources and energy,or from the perspective of global environment restrictive conditions,developing countries can not repeat the old development road of developed countries,either in view of the international pressure China is currently facing,or in view of China’s own resources endowment and stages of development,we must actively face such a challenge of climate change.We must recognize that the issue of climate change may be a great restraint to the present and future eco-social development,and may also be an important driving force and new opportunity to push forward the transformation of development pattern,to take a new road of industrialization and to realize sustainable development.This demands us,on the one hand,to take the Scientific Outlook of Development as the guide to make efforts to control the emission of greenhouse gases and continuously increase the capability of adapting to climatic change,and set up the overall plan to respond to climate change of our country,and on the other hand,we should unswervingly take the road of sustainable development,save energy,optimize energy structure and strengthen biological protection in slowing and adapting to climate change. 相似文献
156.
《International Journal of Sustainable Engineering》2013,6(5):291-302
ABSTRACTDemand of electrical energy is exponentially increasing causing environmental problems due to extensive use of fossil fuels. Hence, research has been promoted in renewable energy technologies to mitigate environmental pollution. Indian subcontinent is rich in renewable energy sources (RES). This paper describes potential of RES and region-wise installed capacity in India. Estimated potential of RES is 57 GW which is targeted to be 175 GW by 2022. A logical framework for our future research work has been presented. This includes performance optimisation of solar pumping system and reliability assessments of the designed system using reliability indices.Abbreviation: RES: Renewable energy resources; SHP: small hydro plants; GOI: Government of India; MNRE: Ministry of New and Renewable Energy; LHP: large hydropower; BCM: billion cubic metres; PEC: per-capita energy consumption; JNNSM: Jawaharlal Nehru National Solar Mission; DNI: direct normal irradiance; SPV: solar photovoltaic; UMPP: ultra mega green solar power project; GIS: geographic information systems; WMS: wind monitoring stations; MPWL: Madhya Pradesh windfarms Ltd.; MIB: mat river basin; SWAT: Soil and Water Assessment Tool; ROR: run of river; SMS: short message service; CDM: clean development mechanism; NIOT: national institute of ocean technology; LOLP: loss of load probability; CSO: Central Statistics Office; CEA: Central Electricity Authority; TERI: The Energy and Resources Institute; WPI: Wind Power India; IEA: International Energy Agency; EAI: Energy Alternatives India; BKP: Biomass Knowledge Portal; IRENA: International Renewable Energy Agency; GAIN: Global Agricultural Information Network; NITI: National Institution for Transforming India; NIWE: National Institute of Wind Energy; UP: Uttar Pradesh; J&K: Jammu and Kashmir; HP: Himachal Pradesh; NR: northern region; MP: Madhya Pradesh; WR: western region; TN: Tamil Nadu; AP: Andhra Pradesh; SR: southern region; ER: eastern region; NER: north eastern region; A&N: Andaman & Nicobar 相似文献
157.
Ting-Long Pan Hong-Shu Wan Zhi-Cheng Ji 《International Journal of Sustainable Engineering》2014,7(2):103-110
This paper presents a stand-alone wind power system with battery/supercapacitor hybrid energy storage. A stand-alone wind power system mainly consists of a wind turbine, a permanent magnet synchronous generator, hybrid energy storage devices based on a vanadium redox flow battery and a supercapacitor, an AC/DC converter, two bidirectional DC/DC converters, a DC/AC converter and a variable load. Several control strategies for the stand-alone wind power system are involved such as a maximum power point tracking (MPPT) control, a vanadium redox flow battery charge/discharge control and a supercapacitor charge/discharge control. The proposed MPPT control combines a sliding mode control with an extreme search control to capture maximum wind energy. This strategy avoids the necessity of measuring wind velocity, obtaining models or parameters of the wind turbine and calculating the differentials of the power generated from the wind power system and from the speed of the generator. The battery charge/discharge control maintains a constant DC bus voltage. When the battery charging/discharging current reaches the setting threshold, the charge/discharge control of the supercapacitor is triggered to limit the charging/discharging current of the battery. The simulation results show that the proposed method can rapidly respond to variations in wind velocity and load power. 相似文献
158.
赵峰涛 《再生资源与循环经济》2011,4(7)
介绍了中国平煤神马能源化工集团有限责任公司,积极转变经济发展方式,大力发展循环经济和低碳经济,努力打造和完善我国目前最高端的煤基化工产业链,在产业链延伸的过程中实现资源利用效率最大化,碳排放最小化的具体经验。 相似文献
159.
闫启平 《再生资源与循环经济》2012,5(2):4-9
废钢铁产业是我国再生资源产业的主体,其节能减排、低碳环保和不可替代的钢铁原料功效十分显著。阐述了我国废钢铁产业在经济转型中的主导地位、应用价值、投资环境及今后的发展战略。指出我国经济发展方式的转变,赋予了废钢铁产业良好的发展机遇和重大的历史使命,中国废钢产业具有良好的投资市场和巨大的发展空间。 相似文献
160.