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91.
黄永明 《广东化工》2003,30(2):72-74
本文简述了在双氧水生产装置上应用变频调速技术对物料输送系统改造,实现有效节省能耗,降低生产成本,提高生产效率。  相似文献   
92.
In this paper, we discuss the design of a new Medium Access Control (MAC) protocol, SRI-MAC (Synchronous Receiver Initiated MAC), for wireless sensor networks whose goal is to extend the lifetime of the network by avoiding major energy waste causes, such as collisions, overhearing and idle listening.  相似文献   
93.
The exponential growth of Internet during the last decade leads us to make more efforts in the researching and developing of sustainable Web servers in order to decrease the global energy demand. In this paper, we cover, as a first step, a proper review of the literature related to the energy efficiency research in Web server systems to depict the state of the art to plan further contributions as more research in sustainable Web systems. We also propose and implement an energy metric that permits to establish a relation between the Quality of Service (QoS) obtained by the system and the power it consumes.  相似文献   
94.
A model permits analysis of the influence of temperature on permeate recovery and energy consumption. The proposed model is based on the following assumptions: (1) membrane morphology is temperature-independent; (2) membrane rejection and other transport characteristics of membranes are position-independent; (3) specific water permeability of membranes was based on exponential dependence of viscosity vs. temperature; (4) temperature-dependence depembrane rejection is assumed to be linear. This allows for analyzing the influence of channel geometry, feed concentration, flow rate and temperature on permeate recovery and energy consumption. Calculated data are included. The solutionpresented can be segmented andbuilt into systems for comprehensive techno-economic evaluation of the RO-based process where temperature-dependence of process characteristics has to be considered.  相似文献   
95.
乙烯装置急冷系统能量回收工艺特点分析   总被引:1,自引:0,他引:1  
孙晓 《乙烯工业》2003,15(4):46-47
乙烯装置急冷系统接收来自炉区的高温裂解气,为降低乙烯装置能耗,必须尽可能回收裂解气中的热量。文中针对KBR乙烯流程,介绍了乙烯装置急冷系统能量逐步回收的过程及其工艺特点。  相似文献   
96.
我国的节能减排问题日趋突出。本文从文献梳理角度对我国节能减排的现状、存在的问题以及解决路径进行了述评。研究显示,我国节能减排潜力巨大,节能减排效率低下。直接原因是由于我国产业结构、外贸结构、FDI 结构以及技术结构不合理造成的,但其背后更深层次的原因主要体现在:(1)GDP锦标赛下政治晋升制度的不合理导致了环境的负外部性;(2)激励与约束机制不完善导致政府缺乏节能减排的动力;(3)分税制的不完善导致了我国产业结构的不合理。为此,我们需要从优化产业结构、调整外贸结构、弱化 FDI的“污染避难所”效应以及增强技术进步效应入手,通过改革 GDP 锦标赛下政治晋升制度、完善激励与约束机制、调整财税体制等途径解决我国节能减排问题。  相似文献   
97.
挖沙船上主电机在采用变频调速以前,多用星三角起动或自耦减压起动方式。这种启动方式起动电流较大,导致所选用的柴油发电机的容量过大。采用变频调速以后,可以减小电动机的起动电流,降低柴油发电机的容量,减少前期投资,给企业带来可观的经济效益。  相似文献   
98.
Using atomic force spectroscopy, we investigated the adhesion-promoting ability of chromium. An intermediate layer of chromium can overcome the low adhesion between metal films and silicon dioxide. For the first time, we quantitatively studied this experimentally well known fact. We compared the adhesion between chromium and different substrates such as gold, silver, mica, and silicon dioxide and, beyond that, the adhesion between silicon dioxide and the same substrates. To avoid additional effects due to water, we chose ethanol as a nonpolar solvent. Taking the interfacial energies of the surfaces with the liquid into account eliminates the direct influence of the fluid medium on the adhesion of the solid material. The results we obtained corroborate the experimental fact of higher adhesion of chromium with the chosen substrates, as well as substantiate the value of chromium as an adhesion promoter. The adhesion of chromium-coated probes on gold, silicon dioxide, and mica is higher than the adhesion of silicon dioxide probes on the same substrates.  相似文献   
99.
使用RAMAN光谱和DTA方法研究了含少量Na+和Ti4+的CaO-Al2O3-SiO2系玻璃,发现在纯CAS系玻璃(Ca/Al≥1/2,Al/Si≤1)中,Al3+仅有一部分进入玻璃网络,少量Na+的引入,有助于Al3+进一步进入玻璃网络中,Na+起了间接补强玻璃网络的作用,Na+和Ca2+离子对Al3+进入玻璃网络结构程度的影响可认为是Na+和Ca2+离子分别以[AlO4]Na和[AlO4]Ca[AlO4]基团的形式进入玻璃网络中,由于结合几率和体积效应,使[AlO4]Na较[AlO4]Ca[AlO4]更易进入玻璃网络中。Ti4+以[TiO4]的形式进入玻璃网络,它对Al3+是否能进入玻璃网络无明显影响。Na+和Ti4+的单独引入,均能使玻璃网络的聚合程度增强,析晶活化能提高;而当Na+和Ti4+同时引入时,玻璃网络聚合程度和纯CAS系玻璃相差不大,析晶活化能有所降低。少量Na+的引入,不会影响析出主晶相的种类和数量,而Ti4+的引入,则会影响到所析出主晶相的种类和数量。  相似文献   
100.
This article discusses the practicality of replacing portland cements with alternative hydraulic cements that could result in lower total CO2 emissions per unit volume of concrete of equivalent performance. Currently, the cement industry is responding rapidly to the perceived societal need for reduced CO2 emissions by increasing the production of blended portland cements using supplementary cementitious materials that are principally derived from industrial by-products, such as blast-furnace slags and coal combustion fly ashes. However, the supplies of such by-products of suitable quality are limited. An alternative solution is to use natural pozzolans, although they must still be activated either by portland cement or lime or by alkali silicates or hydroxides, the production of all of which still involves significant CO2 emissions. Moreover, concretes based on activated pozzolans often require curing at elevated temperatures, which significantly limits their field of application.The most promising alternative cementing systems for general concrete applications at ambient temperatures currently appear to be those based at least in part on calcium sulfates, the availability of which is increasing due to the widespread implementation of sulfur dioxide emission controls. These include calcium sulfoaluminate-belite-ferrite cements of the type developed in China under the generic name “Third Cement Series” (TCS) and other similar systems that make good use of the potential synergies among calcium sulfate, calcium silicate and calcium aluminate hydrates. However, a great deal more research is required to solve significant unresolved processing and reactivity questions and to establish the durability of concretes made from such cements. If we are to use these potentially more CO2-efficient technologies on a large enough scale to have a significant global impact, we will also have to develop the performance data needed to justify changes to construction codes and standards.  相似文献   
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