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Accounting cycle

Most new gas and oil-fueled furnaces and boilers have similar efficiencies. The range of efficiency has narrowed with the introduction of minimum efficiency standards for new products sold since 1992. New gas and oil heating equipment currently available in the marketplace have /knnual Fuel Utilization Efficiency (AFUE) ratings of at least 78 to 80 percent. /VFUE is a measure of how efficient a furnace operates on an annual basis and takes into account cycling losses of the furnace or boiler. It does not include the... [Pg.541]

For batch reactors, account has to be taken of the time required to achieve a given conversion. Batch cycle time is addressed later. [Pg.26]

The last part of this account will be devoted to protein kinases and protein phosphatases and some recent results we have obtained for them. Protein kinases and phosphatases are signaling biomolecules that control the level of phosphorylation and dephosphorylation of tyrosine, serine or threonine residues in other proteins, and by this means regulate a variety of fundamental cellular processes including cell growth and proliferation, cell cycle and cytoskeletal integrity. [Pg.190]

It has been detected spectroscopically in great abundance, especially in the hotter stars, and it is an important component in both the proton-proton reaction and the carbon cycle, which account for the energy of the sun and stars. [Pg.6]

A typical example, from the extensive study by Kamakin on an alumina-silica gel, is shown in Fig. 3.32. When the mercury pressure was reduced to 1 atm at the end of the first cycle, 27 per cent of the intruded mercury was retained by the sample a second intrusion run followed a different path from the first, whereas the second extrusion curve agreed closely with the first. Change in f re structure of the kind described above could perhaps account for the difference between the two intrusion curves, but could not explain the reproducibility of the remainder of the loop. There is no doubt that hysteresis can exist in the absence of structural change. [Pg.183]

In all appHcations involving zirconia, the thermal instabiHty of the tetragonal phase presents limitations especially for prolonged use at temperatures greater than - 1000° C or uses involving thermal cycling. Additionally, the sensitivity of Y—TZP ceramics to aqueous environments at low temperatures has to be taken into account. High raw material costs have precluded some appHcations particularly in the automotive industry. [Pg.325]

Product innovation absorbs considerable resources in the fine chemicals industry, in part because of the shorter life cycles of fine chemicals as compared to commodities. Consequently, research and development (R D) plays an important role. The main task of R D in fine chemicals is scaling-up lab processes, as described, eg, in the ORAC data bank or as provided by the customers, so that the processes can be transferred to pilot plants (see Pilot PLANTS AND microplants) and subsequently to industrial-scale production. Thus the R D department of a fine chemicals manufacturer typically is divided into a laboratory or process research section and a development section, the latter absorbing the Hon s share of the R D budget, which typically accounts for 5 to 10% of sales. Support functions include the analytical services, engineering, maintenance, and Hbrary. [Pg.436]

In the geochemistry of fluorine, the close match in the ionic radii of fluoride (0.136 nm), hydroxide (0.140 nm), and oxide ion (0.140 nm) allows a sequential replacement of oxygen by fluorine in a wide variety of minerals. This accounts for the wide dissemination of the element in nature. The ready formation of volatile silicon tetrafluoride, the pyrohydrolysis of fluorides to hydrogen fluoride, and the low solubility of calcium fluoride and of calcium fluorophosphates, have provided a geochemical cycle in which fluorine may be stripped from solution by limestone and by apatite to form the deposits of fluorspar and of phosphate rock (fluoroapatite [1306-01 -0]) approximately CaF2 3Ca2(P0 2 which ate the world s main resources of fluorine (1). [Pg.171]

The linear damage rule takes no account of the orderin which the stress cycles are appHed. [Pg.90]

This cycle accounts for 30—50% of the total photochemical ozone loss observed during spring in the lower stratosphere at mid-north latitudes (76). [Pg.495]

Halogen radicals account for about one-third of photochemical ozone loss observed in the spring in the lower stratosphere (below 21 km) at 15—60°N latitude (76). The following three cycles (4—6) are the most important. Rate constant data are given in Reference 11. [Pg.496]

This cycle is terrninated by the reaction of chlorine atoms with methane Cl + CH — HCl + CH3. The importance of this cycle depends on the avadabiLity of oxygen atoms and varies with altitude as well as the time of year it accounts for only 5% of the halogen-controUed loss at 15 km, but increases to 25% at 21 km. [Pg.496]

The cycle accounts for - 30 and 20—30% of the halogen-controUed loss for chlorine and bromine, respectively. [Pg.496]

The cycle accounts for 20—25% of the halogen-controUed loss (M is a third body molecule). The possible contribution of naturaUy occurring iodine compounds to ozone destmction (via I and lO radicals) is being investigated (79). [Pg.496]

The difference between life cycle costs and the traditional accounting cost is that traditional costs are fairly easy to quantify, whereas life cycle costs are usually difficult to quantify and are usually either lumped iato general overhead costs or ignored altogether. They are very real, however, and when examined ia detail and fully quantified, the economics of composites allow them to displace the traditional materials. [Pg.98]

Natural mbber was also used extensively in its oil-extended form in winter tires in the 1970s (57). Use of oil-extended natural mbber treads, found to have excellent traction on ice and snow, superseded studded synthetic mbber treads when studs were banned in certain countries and states owing to the damage they cause to partially cleared roads. This concept has been extended into aH-season tires, which account for over 75% of original equipment and replacement tires in the United States. It has been shown (58) that part replacement of styrene—butadiene mbber (SBR) in the formulation of aH-season tire tread compounds with oil-extended natural mbber increases ice and snow traction, reduces rolling resistance, and has no effect on normal wet grip. Also, there is only a minor trade-off in wear performance, because below a tire surface temperature of approximately 32°C, the wear of natural mbber is superior to SBR, whereas above this temperature the reverse is tme (59). Thus, wear of an aH-season tire ultimately depends on the surface temperature of the tread over its annual cycle of temperatures. [Pg.272]

Scaling Up Test Results The results of small-scale tests are determined as dry weight of sohds or volume of filtrate per unit of area per cycle. This quantity multiplied by the number of cycles per day permits the calculation of either the filter area reqiiired for a stipulated daily capacity or the daily capacity of a specified plant filter. The scaled-up filtration area should be increased by 25 percent as a factor of uncertainty. In the calculation of cycle length, proper account must be made of the downtime of a batch filter. [Pg.1706]

The application of waste-management practices in the United States has recently moved toward securing a new pollution prevention ethic. The performance of pollution prevention assessments and their subsequent implementation will encourage increased activity into methods that 1 further aid in the reduction of hazardous wastes. One of the most important and propitious consequences of the pollution-prevention movement will be the development of life-cycle design and standardized hfe-cycle cost-accounting procedures. These two consequences are briefly discussed in the two paragraphs that follow. Additional information is provided in a later subsection. [Pg.2163]

As a result we propose the technique of Mo, W, and Re determination in production cycle solutions with the use of peak of non-coherent scattered primary radiation in order to take into account the matrix influence on the analytical signal. The accuracy of the results was checked by the input-found technique. [Pg.444]


See other pages where Accounting cycle is mentioned: [Pg.139]    [Pg.144]    [Pg.149]    [Pg.149]    [Pg.150]    [Pg.350]    [Pg.231]    [Pg.139]    [Pg.144]    [Pg.149]    [Pg.149]    [Pg.150]    [Pg.350]    [Pg.231]    [Pg.47]    [Pg.1064]    [Pg.540]    [Pg.140]    [Pg.91]    [Pg.345]    [Pg.347]    [Pg.288]    [Pg.393]    [Pg.45]    [Pg.150]    [Pg.113]    [Pg.523]    [Pg.6]    [Pg.132]    [Pg.495]    [Pg.495]    [Pg.283]    [Pg.465]    [Pg.215]    [Pg.164]    [Pg.368]    [Pg.742]    [Pg.1722]    [Pg.2164]   
See also in sourсe #XX -- [ Pg.149 , Pg.150 ]




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