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71.
V. A. Roginsky T. K. Barsukova A. A. Remorova W. Bors 《Journal of the American Oil Chemists' Society》1996,73(6):777-786
The relative reactivities as well as the stoichiometric coefficients for a number of flavonoids, catechols, and—for comparison—standard
phenolic antioxidants were determined by analyzing the kinetics of oxygen consumption in organic and micellar systems, with
peroxidation initiated by lipid- and water-soluble azo initiators. The results demonstrated that the flavonoids did not behave
as classic phenolic antioxidants such as α-tocopherol, but showed only moderate chain-breaking activities. The results were
in line with other structure-activity relationship studies on the importance of the B-ring catechol structure, the 2,3-double
bond, and the 3,5-hydroxy groups. The data are discussed in view of possible explanations of the deviations flavonoids reveal
in their behavior compared with regular phenolic antioxidants. 相似文献
72.
Marcus T. Schmitz Bashir M. Al-Hashimi Petru Eles 《Design Automation for Embedded Systems》2002,6(4):401-424
In this paper, we introduce the LOPOCOS (Low Power Co-synthesis) system, a prototype CAD tool for system level co-design. LOPOCOS targets the design of energy-efficient embedded systems implemented as heterogeneous distributed architectures. In particular, it is designed to solve the specific problems involved in architectures that include dynamic voltage scalable (DVS) processors. The aim of this paper is to demonstrate how LOPOCOS can support the system designer in identifying energy-efficient hardware/software implementations for the desired embedded systems. Hence, highlighting the necessary optimization steps during design space exploration for DVS enable architectures. The optimization steps carried out in LOPOCOS involve component allocation and task/communication mapping as well as scheduling and dynamic voltage scaling. LOPOCOS has the following key features, which contribute to this energy efficiency. During the voltage scaling valuable power profile information of task execution is taken into account, hence, the accuracy of the energy estimation is improved. A combined optimization for scheduling and communication mapping based on genetic algorithm, optimizes simultaneously execution order and communication mapping towards the utilization of the DVS processors and timing behaviour. Furthermore, a separation of task and communication mapping allows a more effective implementation of both task and communication mapping optimizationsteps. Extensive experiments are conducted to demonstrate the efficiency of LOPOCOS. We report up to 38% higher energy reductions compared to previous co-synthesis techniques for DVS systems. The investigations include a real-life example of an optical flow detection algorithm. 相似文献
73.
With worldwide energy consumption rising, there is a need to reduce energy use of the housing stock. While this general idea is well-known, there is an overwhelming amount of product data and manufacturers claims through which the homebuilder or designer must sort to make informed selections of energy-efficient upgrades. The main objective of this research was to identify cost effective–energy efficient upgrades from a group of 16 commonly available choices, and rank them according to the most beneficial for the least cost. This study was conducted in Phoenix, Arizona, and included a sample of 30 production-style homes typical of the Phoenix metropolitan area. Energy-simulation software was used to perform energy evaluations and derive the benefits of each upgrade. The cost of each upgrade was obtained from a database of national average costs and from a local context. Differences in the selection of beneficial upgrades vary dramatically with the source of the cost information. This research provides a generic methodology that can be used by builders and designers to select appropriate energy-efficient upgrades for a given geographic area that will provide high operating benefits relative to the amount of capital investment. 相似文献
74.
广州市住宅直饮水设计定额的确定 总被引:1,自引:0,他引:1
对住宅直饮水系统的实际运营情况进行了分析,运营中出现的销售水量低于直饮水定额、制水设备实际工作时间低于额定时间及水表工作不正常等现象都反映了现行直饮水设计定额的不合理性,建议将用水量定额定为5~8L/(户·d),既符合实际情况又能满足居民远期需求。 相似文献
75.
In this study forecast of Turkey's net electricity energy consumption on sectoral basis until 2020 is explored. Artificial neural networks (ANN) is preferred as forecasting tool. The reasons behind choosing ANN are the ability of ANN to forecast future values of more than one variable at the same time and to model the nonlinear relation in the data structure. Founded forecast results by ANN are compared with official forecasts. 相似文献
76.
《Drying Technology》2007,25(11):1803-1808
Malting is a very intensive, energy-consuming process and, from the point of view of energy, green malt drying is one of the most important operations. Double-deck kiln drying, a variant of single-deck kiln drying, is the most commonly used process, but it is usually manually controlled under empirical control actions. These are the reasons why a research project was carried out based on the computer modeling of these process operations including a software tool named CIMFOOD. A knowledge-based system (KBS) allowing the entire processing-plant dynamic behavior simulation and scheduling concerning thermal energy requirements was developed. 相似文献
77.
Richard D. Prosser 《Energy Economics》1985,7(1):9-12
Four models with different lag structures are used to express final energy demand in OECD from 1960–1982 as a function of real GDP and average energy price. The income and long-run price elasticities are not significantly dependent on the model specification, but the Koyck lag scheme, estimated in its distributed lag form, is found to give the most satisfactory results. The statistical properties of the data together with evidence of trends in the elasticities both suggest that the period of falling real prices prior to 1971 is not comparable to the present period. For the period after 1971, an income elsticity of 1.02 and a long-run price elasticity of -0.37 are obtained. 相似文献
78.
From the results reported here it is suggested that policy decisions about the potential contribution of decentralized energy supply systems to UK industrial energy requirements should be based on the suitability of individual sectors rather than averaged over all sectors. The suitability of decentralized energy sources is evaluated, based on a themodynamic match between source and demand. This suitability criterion is used to identify the most appropriate sector in manufacturing industries for the adoption of decentralized energy supply, leaving aside economic cost considerations and individual site requirements. 相似文献
79.
中部地区水资源总量为39.61亿m3。城市用水与农业、生态用水矛盾突出,城市供水能力不足,水污染问题严重,地下水超采严重,水资源开发利用不协调。该区水资源已无进一步开发利用的潜力,需通过调水工程解决缺水问题。水资源配置思路为从地处松花江上游的丰满水库引水,增加供水能力。 相似文献
80.