Power Dissipation in Spintronic Devices Out of Thermodynamic Equilibrium

Quantum limits of power dissipation in spintronic computing are estimated. A computing element composed of a single electron in a quantum dot is considered. Dynamics of its spin due to external magnetic field and interaction with adjacent dots are described via the Bloch equations. Spin relaxation due to magnetic noise from various sources is described as coupling to a reservoir. Resulting dissipation of energy is calculated and is shown to be much less than the thermal limit, ∼kT per bit, if the rate of spin relaxation is much slower than the switching rate. Clues on how to engineer an energy efficient spintronic device are provided.     

钻井平台电站无功功率动态补偿技术的应用

论述了海洋钻井平台的功率因数及改善功率因数的重要意义和必要性，对实时无功功率动态补偿装置作了介绍，并对实施功率补偿后取得的效果和经济测算作了分析，提出了提高功率因数，进行功率补偿的推广应用建议。     

建筑节能发展缓慢的原因及其对策

我国实施建筑节能已近10年，但仍然只停留在试点、示范的层面上，尚未扩大到整体．分析了造成建筑节能发展缓慢的原因，并提出了推行和普及建筑节能的对策．     

Comments on “Is the cause of size effect on structural strength fractal or energetic-statistical?” by Ba?ant & Yavari [Engng Fract Mech 2005;72:1-31]

Aim of this letter to the Editor is at replying to the criticisms raised by Ba?ant and Yavari [Ba?ant ZP, Yavari A. Is the cause of size effect on structural strength fractal or energetic - statistical? Engng Fract Mech 2005;72:1-31] against the fractal approach to the size-scale effects on the mechanical properties of materials and the concept of the Multi-Fractal Scaling Law presented by Carpinteri [Carpinteri A. Scaling laws and renormalization groups for strength and toughness of disordered materials. Int J Solids Struct 1994;31:291-302]. These criticisms will be analysed thoroughly, showing how they also contain some mistakes and misunderstandings. The presented elucidations should redirect the discussion to a more correct scientific debate.     

原油集输太阳能加热节能技术的应用

在油田的采油、集输等过程中,传统技术使用燃烧煤、油、天然气和电加热方法来实现原油加热,造成大量的能源消耗和严重的环境污染。原油集输太阳能加热计算机控制节能系统,为油田的采油、集输开辟了节能新途径。该系统不仅具有自动化、智能化的特点,而且节能效果显著,实际节气率超过40%。文章介绍了该系统的结构、工作原理、功能特点以及应用效果。     

光声耦合与光子Cooper对

文中研究了光声耦合所导致的光子Cooper对的形成机制，计算了光子Cooper对的能隙（0.01eV）和尺度（10^-5m)以及内禀角动量（奇数），并简要讨论了几十开低温下介质中光的超流效应的可能性。由于在低温下， 光子Cooper对不容易受到热运动的激发，因此有可能存在光的超流现象。     

降温集油技术在朝阳沟油田的应用

精确界定油井温度界限值,对回油温度进行自动控制是降低气耗、能耗的有效措施。首先推导了单井温度界限数值模型,然后针对朝阳沟油田的实际情况对油井进行了分类,并选择了有代表性的单(环)井进行了试验。通过现场实测值与利用模型计算的预测值比对,符合率达到了70%以上。在此基础上利用温度界限分析仪进行了进一步的验证试验,结果符合预期。在单(环)井上加装了掺水量自动控制装置,实现了回油温度的自动控制。     

Geothermal reservoir simulation

This paper is intended to be a state of the art review of geothermal reservoir simulation. Its recent application to the modelling of real geothermal reservoirs is described and put in the context of an emerging general approach to reservoir modelling. The use of computer simulation for geothermal well test analysis is described. One of the main recent uses of reservoir simulators has been for conducting numerical experiments aimed at improving the understanding of geothermal reservoir physics. Such studies on fractured reservoirs, the thermal structure of reservoirs and the effects of non-condensable gases and dissolved salts are outlined.     

Communications on energy: Fighting London's cold war

This communication illustrates the work of the London Energy and Employment Network. LEEN has the twin aims of promoting a rational energy policy for London and, in the process, generating much needed employment. In cooperation with Hackney, one of Britain's poorest boroughs, LEEN organized Hackney's Cold War — a series of initiatives showing the practical measures, informational back-up and funding sources necessary for a local energy policy. LEEN intends to repeat this project in other London Boroughs, with the eventual aim of helping to persuade central government to adopt a more comprehensive approach to energy conservation nationally.     

节能设计在医院综合病房楼建筑工程中的应用

医院建筑能耗高,如在设计阶段对建筑、供暖与通风、给排水、电器照明等各环节进行节能设计,可以起到事半功倍的效果.文中结合工程实践,提出了各种具体节能措施.