水电开发中如何评价高坝大库水电站的效益

本文引用了国内、外水电建设工程的若干数据,证实了高坝大库开发方式的投资、淹没损失和经济效益都比低坝多级开发为优。在我国河流规划中,对高坝大库和低坝径流式开发方式,两者是相辅相成的,不能孰褒孰贬。     

岳城水库提高防洪标准方案分析

岳城水库为病险水库，根据工程地址和水文条件，对提高水库防洪标准方案进行了分析，采用增设第二溢洪道是提高防洪标准的根本措施。     

防洪系统调度的多方案综合评价决策研究

提出了防洪系统调度评价方法的设想，并根据防洪调度决策的特点，提出多方案决策权衡的思路。从实用性、科学性和民主性出发，考虑采用层次分析方法和记录卡片显示法进行防洪决策，两种评价方法综合应用、互相补充。最后论述了长江流域防洪系统实时调度评价的实例应用前景。     

清丰山流域防洪调度决策系统

通过对清丰山流域防洪调度系统数据流程和功能分析，提出了系统的总体框架和设计方案，并重点讨论了洪水预报方法和防洪调度方案等关键技术问题。该系统技术先进、实用可靠、界面友好，可在我国其他流域推广应用。     

网络环境下基于模型驱动的水库群防洪联合调度系统

在分析水库群实时防洪调度特点的基础上，以JBuilder为开发工具，采用Oracle数据库研究开发了结构合理、功能齐全、界面友好和实用性强的网络环境下的水库群防洪联合调度系统。阐述了利用上述平台进行系统设计和开发的关键技术。该系统主要特点是支持异地用户进行联合调度方案的在线制定。支持从洪水预报数据预处理、初始条件设置、水库限制条件选择、模拟调度到决策会商和报表制定等决策制定的全过程。     

水库群防洪调度的大系统多目标决策模型研究

根据大系统多目标决策理论，提出了库区实时防洪调度的多目标决策模型．该模型克服了动态规划法的“维数灾”，并将专家经验和防洪系统的特点结合于实时防洪调度中．实例计算表明，该方法有效地减少洪灾风险，对协调各地区、各部门之间的矛盾，为决策者提供多个实时防洪调度的备选方案．     

基于粗糙熵理论的平原河网防洪规划方案评估模型

平原河网地区城市防洪规划方案的评估是模糊多目标多准则决策问题,其影响因素众多,情况复杂多变,针对目前防洪规划方案评估方法存在的不足,分析了城市防洪规划方案影响因素,建立了评估指标体系,将粗糙集和信息熵理论相结合,构建了基于粗糙熵理论的平原河网防洪规划方案评估模型,并将其应用于苏州市防洪规划方案评估中。结果表明,基于粗糙熵的防洪规划方案评估模型在保证了稳定性的同时也具有较高的精度,能为城市防洪规划方案的评估提供指导。     

防洪基金问题的研究

在研究防洪基金与洪水保险之间关系的基础上，指出防洪基金的建立可以弥补洪水保险中存在的缺陷，加强防洪能力。防洪基金应由国家各级政府及防洪保护区内的受益者共同负担，据此，应用数学优化方法建立了防洪基金模型以确定受益者应缴纳的防洪保护费率。     

洪水遭遇组合下防洪区的洪灾风险率估算

在洪水风险分析的基础上,以洪水遭遇组合规律为分析对象,运用概率组合方法估算了水库下游防洪区的洪灾风险率,以判断当地防洪措施的实际防洪能力,为水库防洪调度方案的制定提供科学依据．     

防洪减灾经济学初探

尝试建立防洪减灾经济学这一崭新学科，在阐明防洪减灾的地区性公共品的经济学特性的基础上，利用博弈论模型研究了现有的防洪减灾机制。发现了其机制上的缺陷，为此，提出了防洪林木产权交易和洪水保险等新机制，并进行了博弈研究，考察了这些机制的均衡结果和条件，为更有效地防洪减灾提出了机制上的建议。     

Negative electrodes for Li-ion batteries

Graphitized carbons have played a key role in the successful commercialization of Li-ion batteries. The physicochemical properties of carbon cover a wide range; therefore, identifying the optimum active electrode material can be time consuming. The significant physical properties of negative electrodes for Li-ion batteries are summarized, and the relationship of these properties to their electrochemical performance in non-aqueous electrolytes, are discussed in this paper.     

河流健康的影响因素及评价思路

分析了影响河流健康的主要因素及河流中关键物种生存及生长状况与河流水资源承载能力、水环境承载能力的相关关系,提出以关键物种的生存及生活态势判度河流的健康状况,为河流健康评价提供了新思路。     

基于功率缺额和可用容量的可靠性优化分析模型

针对现有可靠性优化模型对网络拓扑结构和支路容量约束考虑的不足,在网流模型的基础上,采用交流潮流方程描述支路电气参数,可对系统运行中出现的电压越限状态进行校正,并考虑随机故障对系统可靠性的影响,引入可用传输容量概念,对支路传输容量及发电机容量约束进行修正,建立了以功率缺额最小为目标的可靠性优化分析模型。该模型充分考虑了电力系统可靠性与电网结构、设备停运率、设备修复率、负荷水平等因素的密切联系,反映了系统的实际运行状况。通过算例验证了该模型的有效性。     

大温差空调系统在酒店工程中的应用

从节能考虑,在佛山某酒店项目的设计中应用了大温差空调冷水系统,介绍了本工程的!￡调系统,并给出了空调系统图,同时介绍了空调末端设备的产冷量是如何修正的。     

Experimental investigation of hydrogen storage in capillary arrays

We present the results of the experimental investigation of hydrogen storage in glass capillary arrays. It is demonstrated that quartz–epoxy capillary arrays can have extremely high gravimetric and volumetric capacity, exceeding US DOE 2010 target values. The new method of pressurized hydrogen loading and releasing is developed based on plugging up the capillaries with stoppers in high-pressure environment.     

电网对大规模风电消纳能力分析

随着风电接入电网容量的增加,调峰能力、电网输送空间和安全裕度成为制约电网消纳风电的瓶颈,为此先对电网进行调峰能力计算,得出考虑系统调峰能力约束的风电接纳能力范围,然后计算所选电网的风电场穿透功率极限用以表征风电送出问题,再对风电场并网后的电网进行稳定性分析。并对恩施电网进行实例分析,获得恩施电网的风电消纳能力,验证了该方法的可行性。     

超超临界机组在我国发展的必要性与可行性

超超临界机组在节能和环保方面有很大的优势。在分析我国火力发电机组现状的基础上,得出结论:超超临界机组在中国有其发展的必要性与可行性。     

Adsorption behavior and kinetics of H2S on a potassium-promoted hydrotalcite

Adsorption of H₂S and the influence of steam on its adsorption capacity and kinetics were studied on a commercial potassium-promoted hydrotalcite. The sorbent shows a very high cyclic working capacity for H₂S compared to CO₂ and H₂O, even at lower partial pressures and at different operating temperatures ranging between 300 and 500 °C. The operating temperature does not significantly influence the cyclic working capacity for half-cycle times of 30 min. The adsorption mechanism, however, changes at higher temperatures. At lower temperatures (300 °C) a fast adsorption with a fast approach to steady state was observed. At higher operating temperatures, H₂S reacts with the hydrotalcite structure, forming strongly bonded sulfuric species on the sorbent. When using dry regeneration conditions, the first cycles in cyclic operation at higher temperatures show a significantly higher adsorption of H₂S (especially the first cycle), which cannot be desorbed during regeneration with N₂. After the first fast initial adsorption rate a continuous slow adsorption of H₂S occurs, probably caused by a surface reaction between H₂S and the hydrotalcite structure. This reaction is, however, reversible if steam is used.The adsorption mechanism for H₂S and H₂O was determined using multiple cyclic experiments comparable to previous studies performed for CO₂ and H₂O adsorption. It is evident that the adsorption mechanism developed for CO₂ on the same sorbents is also valid for H₂S, indicating that the developed mechanism is consistent for sour gas adsorption on this type of sorbents. The cyclic working capacity can be significantly increased if steam is used during the regeneration step of the sorbent. The mechanistic model developed for the adsorption of CO₂ and H₂O was successfully validated with more than 160 different TGA experiments. An operating temperature of 400 °C seems to be optimal to achieve a high cyclic working capacity for H₂S, because at higher temperatures the regeneration of the formed sulfuric species seems to be hindered resulting in a significant decrease in the cyclic working capacity.     

Si thin platelets as high-capacity negative electrode for Li-ion batteries

Pure Si platelets and Ni or Cu layer-laminated Si platelets with difference thickness were prepared, and their charge/discharge properties were examined in 1 M LiClO₄/EC + DEC (1:1 by volume) as alternative negative electrode materials to graphite for Li-ion batteries. The shape of thin platelets and lamination with Ni layer are significantly effective to improve the cycleability in Li-Si alloy system by relieving the stress during the alloying/de-alloying processes, reinforcing the mechanical strength and reducing the Li⁺ ion diffusion length. Moreover, the first irreversible capacity is minimized by reduction of the amount of Ketjen Black (KB) in the composite electrode because of electrolyte decomposition on the surface of KB. Consequently, the Si/Ni/Si-LP30 (30/30/30 nm) composite electrode with 5 wt% KB also exhibits over 700 mAh g⁻¹ even after 50 cycles in 1 M LiPF₆/EC + DEC (1:1).     

间隙型增容导线在泸州电网改造中的应用

分析采用间隙型耐热增容导线工程应用的实际意义,为提供输电线路增容改造工程技术支持,以泸州地区110 kV电网增容改造工程为例,比较了间隙型耐热增容导线与同截面普通钢芯铝导线输送容量、弧垂、张力三者与温度变化的关系,并介绍了施工方法。