Totally found 10042166 items.

  • [期刊] The energy saving technology of beneficiation of iron ore
    The qualitative and quantitative evaluation of liberation of economic minerals and the level of contamination of the process products by waste components were carried out for the purpose of analysing the technology level and forecast its development directions. Concentration of intergrown particles into a separate product for the purpose of subsequent more efficient and selective liberation is one of the reserves for energy saving in the grinding operations. A pilot selective separator was tested in re-cleaning operations to compare with a standard (conventional) separator. The tests that showed, that a separator with a pulsed magnetic field is an efficient device that allows the realization of an intensive concentration of a large amount of unliberated magnetic particles - consisting of two phases -value minerals and gangue, into several products.
  • [期刊] What Did They Know and... WHEN DID THEY KNOW IT?
    You can smell the fish sticks from lunch in Sherron Watkins' 60-year-old house near downtown Houston, see the framed pictures of the family vacation and the baby in bunny ears and even one of her country-crooning second cousin, Lyle Lovett. Things have been so hectic, Watkins apologizes, that the Christmas ornaments haven't been put away yet. The daughter of two educators, Watkins grew up in nearby Tomball, where she worked the cash register at the family grocery store and began saving her money. By 1982, she'd picked up two accounting degrees in Austin and quickly found a job with Arthur Andersen. She eventually landed a job with Enron, Houston's red-hot energy trading firm, rising in eight years to vice president for corporate development. Her quick ascent surprised no one, says her husband Rick: "She always had a flair for numbers."
  • [期刊] Content management demystified
    In today's economic climate, utilities and energy companies face the same pressures and business challenges as firms in other industries. Business priorities include attracting new customers, getting closer to existing ones, and fostering loyalty through superior service. Other priorities include complying with industry regulations, optimizing efficiencies in back-office processes, and optimizing IT investments. Finally, saving money is especially critical for utilities that need to improve their bottom line in the face of rate freezes and other limitations on revenue growth.
  • [期刊] L-ascorbic acid and other quality criteria in frozen and dehydrated strawberries Fragaria X ananassa Duch.
    The drying method used was based on the energy saving principle of low-temperature dehydration in a closed cycle with a heat pump connected. Frozen strawberries contained an average of L-ascorbic acid 69 mg/100 g, with higher values for Zefyr (94 mg/100 g) and Bounty (89 mg/100 g) cultivars. The loss of L-ascorbic acid after dehydration was on average about 30%.
  • [期刊] An improvement of performance in steam turbine by developing three-dimensionally designed blades
    From the viewpoint of reducing power generation costs and saving energy resources, improved efficiency of thermal power plants is a critical issue. Steam turbines, which are the main plant equipment, have been developed which provide a high levelin blade performance. Further enhancement of blade performance, however, requires refinement of the blade shape and the control flow pattern in the radial direction. Recently, development of three dimensionally designed blades has been active, with goalsof raising the internal efficiency and being able to the control flow pattern in the radial direction not only for stationary blades, but also for moving blades. In order to improve the flow pattern through the blade rows, the authors have proposed threedimensionally designed stationary blades, which can be used in low pressure (LP) and high and intermediate pressure (HIP) turbines. This paper describes the development of three-dimensionally designed blades, in which performance of turbine stagesincluding moving blades has been improved. The new blades reduce the end-wall losses in the HIP stages where there is a serious problem with secondary flow.
  • [期刊] Silver-based low-emissivity coatings for architectural windows: Optical and structural properties
    Spectrally selective coatings are, nowadays, deposited onto architectural windows to be employed in commercial and residential buildings for the purpose of saving energy. In this work, the fundamental optical and structural properties of two types of low-emissivity silver-based coatings deposited onto glass, Ag and SnO2/Ni-Cr/Ag/Ni-Cr/SnO2 (Vitrage a couches avec une forte reflexion des rayonnements thermiques, European Patent EP 0 506 507 B1) are analyzed. It has been demonstrated that the silver-based multilayer coatings give an efficient heat isolation due to their low emissivity values, thus not deteriorating the optical properties in the visible range given by the glass substrate. From Atomic Force Microscopy measurements it has been determined that the Ag layer has a more homogeneous grain size when is deposited onto the Ni-Cr layer than when is deposited onto glass. (C) 1998 Elsevier Science B.V. All rights reserved. [References: 11]
  • [期刊] America's energy supply
    The gist of the paper is to demonstrate that the economical utilization of the country's energy supply requires generating electric power wherever hydraulic or fuel energy is available, and collecting the power electrically, just as we distributeit electrically.In the first section a short review of the country's energy supply in fuel and water power is given, and it is shown that the total potential hydraulic energy of the country is about equal to the total utilized fuel energy.In the second section it is shown that the modern synchronous station is necessary for large hydraulic powers, but the solution of the problem of the economic development of the far more numerous smaller water powers is the adoption of the inductiongenerator. However, the simplicity of the induction generator station results from the relegation of all the junctions of excitation, regulation, and control to the main synchronous station. The economic advantage of the induction generator station is,that its simplicity permits elimination of most of the hydraulic development by using, instead of one large synchronous station, a number of induction generator stations and collecting their power electrically.The third section considers the characteristics of the induction generator and the induction-generator station, and its method of operation, and discusses the condition of "dropping out of step of the induction generator and its avoidance.In the appendix the corresponding problem is pointed out with reference to fuel power, showing that many millions of kilowatts of potential power are wasted by burning fuel and thereby degrading its energy, that could be recovered by interposing simplesteam turbine induction generators between the boiler and the steam heating systems, and collecting their power electrically. It is shown that the value of the recovered power would be an appreciable part of that of the fuel, and that organized andcontrolled by the central stations, this fuel power collection would improve the station load factor, give the advantages of the isolated plant without its disadvantages, and produce a saving of many millions of tons of coal.
  • [期刊] A magnetic coupled charger with no-load protection
    A novel magnetic coupled charger is proposed, that is suitable for small electric devices. In this charger, standby power is reduced for energy saving. Eddy current heating in metal placed near it, is reduced by using a feedback transformer. In this circuit, a power factor correction is also realized to be 99%.
    There is still a savings potential, even with the very latest brick and tile plants. Further optimization, however, is becoming ever more difficult, because the degree of efficiency of the plants is constantly increasing. An energy-saving combination is the condition for this optimization : 1. changes in formulation and preparation of raw materials; 2. simplified handling operations; 3. optimization of dryer-kiln aggregate; 4. 7-day operation and production management.
  • [期刊] Fire protection of critical circuits - a life and property preserver
    This paper examines the importance of fire-resistant electrical circuit feeders in saving lives and property. It discusses sophisticated fire fighting and evacuation systems and the electrical energy requirements to ensure their operation incommercial high-rise, hospital, and other at-risk buildings. The influence of cost, ease of installation, and subsequent inspection of fire-resistant circuits in a consulting engineer's specifications decision is considered. Analysis of the impact ofbuilding code modifications that require increased fire protection for feeders to emergency systems is presented. The paper cites examples of devastating fires and resultant code upgrades. Implications of the 1996 National Electrical Code (NEC) sectionsconcerning emergency electrical feeders are reviewed. Specification writers and product installers have primary influence over these systems. Their roles and responsibilities are discussed. The paper also reviews the various methods of providingfire-resistive protection to circuit feeders.