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Cleaning reliability

Natural gas a clean, reliable, and energy-efficient fuel an odorless, colorless, combustible fuel. These attributes accurately characterize the form of energy known as natural gas. Nevertheless, we are constantly advised to contact the gas service company whenever we detect the smell of gas as a precautionary measure to locate leaks. An examination of the chemical composition of natural gas can explain this paradox. [Pg.180]

The overarching drivers for the development of hydrogen technologies are climate change and reductions in oil consumption with additional benefits in emissions reductions. The use of hydrogen in fuel cell vehicles can reduce oil use and carbon plus other emissions in the transportation sector, while hydrogen can enable clean, reliable energy for stationary and portable power applications. [Pg.39]

The CCEF recently issued the 2002 Fuel Cell Request for Proposal (RFP) to promote clean, reliable distributed generation in Connecticut and the commercialization of fuel cells. The funding level for the 2002 Fuel Cell RFP could reach almost 9 million. [Pg.13]

Simple, easily repaired and cleaned, reliable, inexpensive. [Pg.100]

In Thailand, DMFC fuels cells have been seriously considered to power scooters with minimum cost and complexity. In the transportation segment, there is great interest in the design and development of low-cost fuel cells to provide a clean, reliable, and safe alternate power source of electrical energy. These low-cost, low-power fuel cells can be designed to meet the energy demand ranging from 1 to 10 kWh capacity. [Pg.41]

The tin bronzes hardness inhibits them from conforming easily to rough or misaligned shafts. Similarly, they do not embed dirt particles well and therefore must be used with clean, reliable lubrication systems. They require a shaft hardness between 300 and 400 BHN. Tin bronzes operate better with grease lubrication than other bronzes. They are also well suited to boundary-film operation because of then-ability to form polar compounds with small traces of lubricant. Differences in mechanical properties among the tin bronzes are not great. Some contain zinc as a strengthener in partial replacement for more expensive tin. [Pg.629]

Tide V of the Clean Air Act Amendments of 1990 covers federally approved state operating permits for manufacturing faciUties. One requirement of this regulation is that manufacturers must report emissions information of identified ha2ardous air pollutants specific to thein operation from a list of 189 named in the Clean Air Act Amendments. Rubber and tine manufacturers had to meet this requirement by the end of 1995. The Rubber Manufacturers Association has begun an industrywide project to develop accurate and reliable emissions data to aid manufacturers to comply with these requinements (44). [Pg.500]

Pneumatic controllers are made of Bourdon tubes, bellows, diaphragms, springs, levers, cams, and other fundamental transducers to accomplish the control function. If operated on clean, diy plant air, they offer good performance and are extremely reliable. Pneumatic controllers are available with one or two stages of pneumatic amphfi-cation, with the two-stage designs having faster dynamic response characteristics. [Pg.776]

Flow measurements using nonintrusive or low mechanical ac tion principles are desired, such as magnetic, vortex-shedding, or Coriolis-type flowmeters. Orifice plates are easy to use and reliable but have a limited range and may not be suitable for streams which are not totally clean. Rotameters with glass tubes should not be used. [Pg.2309]

Until a few years ago these breakers had been quite common for medium voltages, up to 33 kV. Since they require a powerful blast of air at high pressure and velocity into the arcing region, they require a reliable source of air supply. Air should be clean and dry and at the correct... [Pg.636]

As stated, the dry gas seal does come with its own set of disadvantages. The biggest of these is that the buffer gas must be reliable. Loss oi buffer gas in some cases will reverse the differentia] pressure across (iie seal faces, which will damage the seal in short order. The seals will opei ate at a zero differential pressure level, but when possible, even a small differential in the proper direction is recommended by the manufacturers. Another disadvantage is the requirement for clean and dry gas at the seal... [Pg.216]

Because LEED theory was initially developed for close packed clean metal surfaces, these are the most reliably determined surface structures, often leading to 7 p factors below 0.1, which is of the order of the agreement between two experimental sets of 7-V curves. In these circumstances the error bars for the atomic coordinates are as small as 0.01 A, when the total energy range of 7-V curves is large enough (>1500 eV). A good overview of state-of-the-art LEED determinations of the structures of clean metal surfaces, and further references, can be found in two recent articles by Heinz et al. [2.272, 2.273]. [Pg.82]

Electronics cleaning - For most uses in the electronics industry, ozone-depleting solvents can be replaced easily and, often, economically. A wide choice of alternatives exists. If technical specifications do not require postsolder cleaning, noclean is the preferred technology. If cleaning is required, the use of water-soluble chemistry has generally proved to be reliable. There are however limitations, whereby water-soluble chemistry is not suitable for all applications. [Pg.37]

Categories for exhaust air (EHA) are also defined in prEN 13779. Normally the EHA category for air to be discharged outdoors is the same as ETA, but if the system includes reliable and monitored cleaning equipment, the category can be one lower. With these provisions, air from industrial processes with very high pollution level, in category ETA 4 can be cleaned to EHA 3 levels. [Pg.804]

In order to verify that the products or services meet the specified requirements you will need to carry out tests, inspections, assessments, etc. and these need to be performed against unambiguous standards of acceptability. You need to establish for each requirement that there are adequate criteria forjudging compliance. You need to establish how reliable is reliable , how safe is safe , how clean is clean , how good is good quality . Specifications often contain subjective statements such as good commercial quality, smooth finish, etc., and require further clarification in order that an acceptable standard can be attained. The secret is to read the statement then ask yourself if you can verify it. If not, select a standard that is attainable, unambiguous, and acceptable to both customer and supplier. [Pg.195]

The Department of Energy fosters a secure and reliable energy system that is environmentally and economically sustainable, acts as a responsible steward of the nation s nuclear weapons, and seeks methods to clean up our own facilities and to support continued United States leadership in science and technology. [Pg.287]

In the CCPS Taxonomy, four degrees of severity, from clean to severe, are used to characterize the process medium—the material being handled by the equipment—and its influence on reliability. In some cases, the severity will be unknown. Even if a severity is listed, doubt may exist about its value, since the definitions of severity are fairly subjective. [Pg.12]

The need for long-term clean power will be a controversial but necessary issue in the twenty-first cen-tuity. The debate will focus on the deregulation of the power industity and the needs of consumers, coupled with what is best for the environment. For certain applications, solar technology has proven to be efficient and reliable. The question remains whether solar will be wholly embraced as energy options for a sustainable future m a climate of cheap fossil fuels and less than enthusiastic public support. [Pg.1068]

Other cleaning methods. Other cleaning methods of proven reliability are permitted. [Pg.593]

Abrasive blasting is generally the most suitable and reliable method of obtaining a visually clean surface and a... [Pg.133]

Reliable enclosed filters of ample effective filtering area should be used for both stages. The filter design should not allow the pressure drop to exceed 7kN/m (1 Ibf/in ) across second-stage fine filters in clean conditions. Filters should preferably be of the duplex or self-cleaning type, and installed so that oil spillage will not occur during operation. [Pg.256]

Some 70-85 per cent of failures and wear problems in lubricated machines are caused by oil contamination. Clean oil extends machine and oil life and gives greater reliability, higher productivity and lower maintenance cost. Hence, some type of filter is an essential part of virtually all lubrication systems. [Pg.881]

Reliable contractors should carry out all boiler treatment and cleaning. Boilers are fired pressure vessels and are subject to mandatory insurance inspections. Significant benefits in safe and economic operation, particularly by reducing unnecessary chemical treatment, can be achieved by monitoring the condition of boilers. [Pg.901]

It is essential that all major maintenance work and findings are recorded in the plant running log as a guide to the reliability of components, the need for cleaning, and other indicators to future work. [Pg.344]

The differential capacitance method cannot be used for reactive metals, such as transition metals in aqueous solutions, on which the formation of a surface oxide occurs over a wide potential re ion. An immersion method was thus developed by Jakuszewski et al. 3 With this technique the current transient during the first contact of a freshly prepared electrode surface with the electrolyte is measured for various immersion potentials. The electrode surface must be absolutely clean and discharged prior to immersion.182-18 A modification of this method has been described by Sokolowski et al. The values of obtained by this method have been found to be in reasonable agreement with those obtained by other methods, although for reactive metals this may not be a sufficient condition for reliability. [Pg.38]

Uncertainties in Photochemical Models. The ability of photochemical models to accurately predict HO concentrations is undoubtedly more reliable in clean vs. polluted air, since the number of processes that affect [HO ] and [H02 ] is much greater in the presence of NMHC. Logan et al (58) have obtained simplified equations for [HO ] and [HO2 ] for conditions where NMHC chemistry can be ignored. The equation for HO concentration is given in Equation E6. The first term in the numerator refers to the fraction of excited oxygen atoms formed in R1 that react to form HO J refers to the photodissociation of hydrogen peroxide to form 2 HO molecules other rate constants refer to numbered reactions above. [Pg.92]

As is well known the difficulty of analysis of a sample increases as its complexity increases. Analysis usually commences with a rather nonspecific clean-up step and requires that the separation step that follows be highly selective and depends on a detection step that is as specific as possible. As the selectivity of detection increases there is also an increase in the reliability of the identification and it is possible to reduce the demands made on the selectivity of the preceding separation method. This is the case for radiometric and enzymatic methods and also explains the popularity of fluorescence measurements. The latter obtain their selectivity from the freedom to choose excitation and measurement wavelengths. [Pg.36]


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See also in sourсe #XX -- [ Pg.65 ]




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