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排序方式: 共有8050条查询结果,搜索用时 15 毫秒
971.
This paper evaluates the impact of the US National Energy Plan on energy demand in US commercial and residential buildings. Following a brief historical review of energy use patterns in US buildings, estimates are presented of how the National Energy Plan would affect the sector in terms of fuel expenditures and investment in energy using equipment and structures. The analysis is based on economic-engineering models of energy demand which are currently being used by the US Department of Energy to evaluate conservation programmes. The demand models incorporate behavioural as well as technological determinants and are sufficiently disaggregated to allow consideration of individual components of the National Energy Plan. 相似文献
972.
Eric Dransfield Douglas N. Rhodes 《Journal of the science of food and agriculture》1975,26(4):483-491
Samples of beef M. semitendinosus were heated at different rates at times up to 3 days after slaughter and the texture determined instrumentally. Rapid heating soon after slaughter produced normal shear values for cooked meat but slow heating gave very tough meat. At later times, shear values were unaffected by the heating rate and decreased with increasing time after slaughter. Multivariate analyses of the effects of holding-time after slaughter, heating rate, pH, sample length and weight before and after heating, showed that variations in shear values of meat heated within 18 h after slaughter were largely due to the combined influences of shortening and of muscle pH after heating. 相似文献
973.
The authors examine three residential energy conservation programmes under study and development by the US government. These programmes include setting appliance efficiency targets, developing new thermal standards for housing, retrofitting existing houses to improve thermal performance and a stronger energy conservation programme. The programmes are compared using a model developed for the FEA and ERDA which projects consumption up to the year 2000. The major conclusion is that the programmes can save both energy for the USA and money for individual households. 相似文献
974.
Eric Jungermann B. C. Brown J. J. McBride 《Journal of the American Oil Chemists' Society》1963,40(2):41-43
The reaction of olefins with phosphorus trichloride in the presence of aluminum chloride was recently reported to result in
phosphorus-containing acids or acid chlorides of the type
This new phosphorylation reaction was extended to fatty acid derivatives containing olefinic double bonds, such as methyl
oleate, oleonitrile, oleamide, N,N-dimethyloleamide, olive oil, oleylacetamide and oleyl alcohol. Phosphorylated fatty derivatives
were obtained in good yield in all cases.
Presented at the AOCS meeting in New Orleans, La., 1962. 相似文献
975.
The aim of this study was to determine the impact of the broadening of fuel specifications on the performance of a gas turbine combustor, particularly on soot formation and oxidation, and flame tube durability. Tests were conducted with a fully-developed combustor system, the main measurements comprising total radiation, exhaust smoke and temperatures at different locations. Five fuels were used: kerosine, as aviation fuel; gas oil, as the current industrial gas turbine fuel and possible future aviation fuel; R25 (where 25 is the volume percentage of residual fuel oil in the blend with gas oil), as equivalent to crude oil now in use in many utility gas turbines; and also R50 and R70 to represent future heavier fuels. Combustor pressures were 0.3, 0.7 and 1.0 MPa. Inlet air temperatures were 313, 390 and 460 K. Primary zone air/fuel mass ratios were 12, 15 and 25. Total air/fuel ratios were 60 and 120. Attempts were made to develop a mathematical model of the soot formation-oxidation processes that occur in the system, and to include in the model some parameters to represent the change in fuel properties. In this paper, comparison of the soot formation predictions of the model with the experimental data is seen to be favourable, particularly at full power conditions. 相似文献
976.
Stice Eric; Presnell Katherine; Lowe Michael R.; Burton Emily 《Canadian Metallurgical Quarterly》2006,18(1):95
In T. van Strien, R. C. M. E. Engels, W. van Staveren, and C. P. Herman's (see record 2006-03905-010) comment, they contested the conclusion that dietary restraint scales are invalid measures of acute dietary restriction (E. Stice, M. Fisher, & M. R. Lowe, 2004). The authors respond to their concerns and conclude that researchers should (a) not have to work this hard to find evidence that these scales correlate with dieting restriction, (b) not settle for scales with only weak validity, and (c) use scales that are consistently valid across settings. The authors also discuss new evidence that most weight loss dieters are not achieving the negative energy balance necessary for weight loss, which seems to explain why these scales do not correlate inversely with caloric intake and why those with the highest dietary restraint scores gain more weight over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
977.
978.
Jemelka Ron P.; Wiegand Geoffrey A.; Walker Edward A.; Trupin Eric W. 《Canadian Metallurgical Quarterly》1992,4(2):138
Evaluated the validity of a computer-based test interpretation (CBTI) system for mental health screening in correctional settings. First, 100 adult male felons were administered a brief mental status interview and a series of psychological tests, including the Minnesota Multiphasic Personality Inventory (MMPI), the revised Beta IQ Examination, and the Buss-Durkee Hostility Inventory. Psychiatric diagnoses and CBTI ratings of victimization, violence, suicide, and substance abuse potentials were compared with clinicians' evaluations. Second, CBTI diagnoses of 109 inmates were compared with Diagnostic Interview Schedule (DIS) diagnoses. Last, CBTI risk ratings were compared with institutional infraction records of 1,718 inmates. Agreement with CBTI and clinicians' risk ratings was fair. CBTI agreement with clinicians' and DIS diagnoses ranged from 60–93%. Ways of improving CBTI algorithms and the value of this approach in correctional screening are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
979.
980.
Highy oblique impacts into thick and thin targets 总被引:1,自引:0,他引:1
Eric L. Christiansen Ed Cykowski Javier Ortega 《International Journal of Impact Engineering》1993,14(1-4):157-168
Hypervelocity impact (HVI) tests have been conducted at the JSC Hypervelocity Impact Test Facility (HIT-F) with aluminum projectiles impacting semi-infinite (thick) and thin aluminum plates (with plate thickness to projectile diameter ratios of 6.4 and 0.14, respectively) at impact angles ranging from normal to the plate (0°) to highly oblique (88°). The targets were impacted by solid homogeneous aluminum spheres from 1 mm to 3.6 mm diameter. Results of the HVI tests were not unusual up to 65°, where impact damage is characterized as smooth craters and holes that become progressively elliptical and distended along the projectile flight path. Above 65° angles, however, a transition occurs to an irregularly shaped hole in thin materials and rough bottomed crater in thick targets. Above 80°, multiple damage sites in the targets were formed with the damage areas separated by variable distances of undamaged target surface. Analytical and numerical simulations of the impact process at oblique angles above 65° demonstrates that shock compression and release of the projectile into multiple fragments occurs before the projectile fully engages the target. The resulting projectile fragments are then responsible for the multiple impact sites observed on the targets. 相似文献