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131.
132.
Development of waste heat-driven absorption-based cooling system is inspired for the need of removing high heat flux from the sustainable data centre environment. This paper presents a simulation study of single-stage Lithium Bromide–Water (LiBr–H2O) vapour absorption heat pump for chip cooling. In the present work, a complete thermodynamic analysis of the single-stage LiBr–H2O vapour absorption-based heat pump for chip cooling without a solution heat exchanger is performed and a user friendly graphical user interface (GUI) package including visual components is developed by using MATlab (2008b). The effect of chip heat flux on COP (Coefficient of Performance), flow rates and conductance is examined using the developed package. The model is verified using the data available in the literature which indicates that there is a greater reduction in the absorber load. The influence of chip heat flux on the performance and thermal loads of individual components are studied, and it is concluded that COP decreases from 0.7121 to 0.68924 with increase in chip heat flux. 相似文献
133.
采用人口重心模型,在GIS技术支持下着重对1989-2005年山东省人口重心迁移特征进行了研究,并在此基础上分析人口重心迁移的主要影响因素。结果显示,山东省人口重心接近几何中心,人口重心自东北向西南方向迁移的趋势明显,其移动轨迹呈现出一定的曲折和波动。山东省人口重心迁移受自然、社会经济和政策等多种因素的影响。 相似文献
134.
135.
内源电子受体对剩余污泥释磷行为的影响 总被引:1,自引:1,他引:0
采用生物脱氮除磷工艺中剩余活性污泥所含硝化细菌处理生产废水的新型硝化工艺,将生产废水中所含氨氮转化为硝酸盐,获得一种从污水处理工艺中产生的内源电子受体。研究内源电子受体的产生特征及其用于抑制富磷剩余污泥在重力浓缩过程中磷的释放特征。结果表明:(1)采用剩余污泥处理生产废水工艺用于产生内源电子受体时,最佳曝气时间为24 h,可将液相中氨氮由41.20 mg/L降为0.19 mg/L;同时,硝酸盐由1.14 mg/L升高至32.62 mg/L,可作为一种潜在的内源电子受体用于抑制重力浓缩过程中剩余活性污泥释磷;(2)当内源电子受体硝酸盐浓度为36.16 mg/L时,经后续的重力浓缩(24 h)后,回流液中磷浓度为44.87 mg/L,与浓缩池上清液直接回流(100%回流并积累)相比,磷积累量降低了65.44%;同时,硝酸盐氮在这一过程中发生反硝化,由36.16 mg/L降至4.84 mg/L。同时,与生产废水直接回流(100%回流并积累)相比,该新型工艺引起氨氮积累量仅为17.68%。上述结果表明:采用内源电子受体,不仅可以有效降低生物脱氮除磷工艺中生产废水回流而引起的磷积累量,而且可同步减少氨氮的循环积累量。 相似文献
136.
外加水在渗吸过程中可以促进煤体瓦斯解吸,减小煤层瓦斯含量,从而减少瓦斯事故的发生频率。为了研究含瓦斯煤水分分布规律,采用NMR(核磁共振成像)技术,针对不含瓦斯煤进行定量外加水渗吸实验。研究结果表明:型煤中的水分主要受毛细管力和重力作用的影响;在自下向上吸水和自上向下吸水渗吸过程中,毛细管力作用相同,径向方向上水分扩散速度相近,但在轴向方向上的扩散速度具有明显差异,由于重力作用的影响,分别产生抑制和促进作用;水分三向扩散半径与时间符合朗格缪尔函数关系。 相似文献
137.
基于全生命周期视角核算2011~2019年中国省际建筑碳排放量,采用社会网络分析方法,探究碳排放空间关联网络演化及其影响因素.结果表明:①中国建筑碳排放空间关联网络形态明显存在,网络密度和网络关联数逐渐上升,网络紧密性和稳定性逐渐提高.②上海、浙江、天津、北京和江苏处于碳排放空间关联网络的核心和支配地位.③北京、天津、江苏、内蒙古、上海和山东属于“净受益”板块,接收其他地区的建筑碳排放;广东、重庆、福建和浙江属于“经纪人”板块,实现了建筑碳排放生产端和消费端的动态平衡;其余省份均扮演“净溢出”角色,主动向外省发出建筑碳排放量.板块间的关联关系远大于板块内部的关联关系.④经济发展、空间邻接关系、城镇化、建筑业过程结构和产业结构差异对建筑碳排放空间关联产生显著影响.研究结果可为建筑业区域协同减排提供参考. 相似文献
138.
Pinkert M Leiba A Zaltsman E Erez O Blumenfeld A Avinoam S Laor D Schwartz D Goldberg A Levi Y Bar-Dayan Y 《Disasters》2007,31(3):227-235
Terrorist attacks can occur in remote areas causing mass-casualty incidents MCIs far away from level-1 trauma centres. This study draws lessons from an MCI pertaining to the management of primary and secondary evacuation and the operational mode practiced. Data was collected from formal debriefings during and after the event, and the medical response, interactions and main outcomes analysed using Disastrous Incidents Systematic Analysis through Components, Interactions and Results (DISAST-CIR) methodology. A total of 112 people were evacuated from the scene-66 to the nearby level 3 Laniado hospital, including the eight critically and severely injured patients. Laniado hospital was instructed to act as an evacuation hospital but the flow of patients ended rapidly and it was decided to admit moderately injured victims. We introduce a novel concept of a 'semi-evacuation hospital'. This mode of operation should be selected for small-scale events in which the evacuation hospital has hospitalization capacity and is not geographically isolated. We suggest that level-3 hospitals in remote areas should be prepared and drilled to work in semi-evacuation mode during MCIs. 相似文献
139.
This paper tries to identify the characters that might affect interprovincial migrants'decisions and examine how and why the inftuenee of these characters changed over time individually and synthetically in China during 1985-2005.We have investigated six types of factors,namely,distance,population density,income,employment structure,house price,and migration stock.In addition,we apply the identified factors with a multiple stepwise regression model to a longitudinal dataset,which consists of interprovincial migration flows over the last two decades in China.It is found that different factors have disparate impacts on migration in China,and they can be decomposed into push force in origin area and pull force in destination area.Factors shaping China's interprovincial migration have shifted from traditional factors such as distance to economic factors such as income and employment structure.This paper suggests that more attention should be paid to obtain detailed migration data with spatial information and develop applicable models for migration processes.Our analysis provides references for development planners and policymakers to develop sound population policies to achieve regional sustainable development in China. 相似文献
140.
Kerstin Norman Håkan Alm Ewa Wigaeus Tornqvist Allan Toomingas 《International journal of occupational safety and ergonomics》2013,19(1):53-68
Background. The purpose was to study the test-retest reliability and internal consistency of questions in aquestionnaire concerning working conditions and health and the inter-rater reliability of observations andmeasurements according to an ergonomic checklist. Method. Fifty-seven operators participated in a retestquestionnaire and 58 operators participated in an inter-observer test. Results. The questions had fair to good or higher reliability in 142 of the total of 312. Twenty-seven of the total of 44 variables in the ergonomicchecklist were classified as having fair to good or higher reliability. Conclusions. About half of the questionshad fair to good or higher reliability and can be recommended for further analyses. The majority of variablesin the ergonomic checklist were classified as having fair to good or higher reliability. Low reliability does notnecessarily indicate that the reliability of the test, per se, is low but may signify that the conditions measuredvary over time or that the answers are aggregated in one part of the scale. 相似文献