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排序方式: 共有1351条查询结果,搜索用时 15 毫秒
991.
Joe Stanislaw 《Energy》1985,10(2):165-180
This paper concentrates on the demand side of the natural gas markets. It discusses major issues influencing the penetration of natural gas in energy markets. First, a brief overview of the historical and future role of natural gas is presented. Next, the natural gas demand is discussed in conceptual terms. This is followed by projections of gas demand developed by the International Energy Agency, showing briefly the methodologies available and presenting an illustration of a method for projecting natural gas demand in Western Europe. Finally, the major factors that will influence natural gas penetration are assessed. 相似文献
992.
France Gary A.; Couch Joe; Cauthen Dale; Carpenter Helen; Jones Marilynn; Jordan Peggy; Morgan Catherine; Lottinville Elinor; Neph Louise 《Canadian Metallurgical Quarterly》1979,47(4):760
Administered the Yellow Brick Road, a screening instrument for preschool children, to 504 children. Normative data were obtained using principal-components analysis. Results indicate that all subscales tapped a common factor. The auditory subscale appeared to be the best overall predictor. More normative data are needed regarding this 1st-grade readiness test. (1 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Jue-Chen Liu Joseph R. Feldkamp Joe L. White Stanley L. Hem Nobuo Otsuka Dorothy F. Conroy Chandrashekhar M. Pendharkar Kenneth M. Feld Richard J. Harwood Wayne M. Grim 《Drug development and industrial pharmacy》1987,13(12):2087-2110
The particle morphology of amorphous aluminum hydroxycarbonate was studied by disaggregation induced by phosphate adsorption and direct observation by high resolution transmission electron microscopy. The primary particles are sheet-like and have equivalent diameters of 55A or less. The primary particles are believed to correspond to planar polymers comprised of six-membered rings of aluminum ions joined by double hydroxide bridges. Secondary particles form by attractive interaction of primary particles. The size of the primary particles affects the porosity of the secondary particles. The granulating and tableting properties of two spray dried amorphous aluminum hydroxycarbonates were shown to be related to the size of the primary particles and the porosity of the secondary particles. 相似文献
994.
William J. Mclaughlin Joe L. White Stanley L. Hem 《Drug development and industrial pharmacy》1992,18(19):2081-2094
The isoelectric point of aluminum hydroxycarbonate suspension increases upon dilution with deionized water. The increase in the isoelectric point is directly related to the degree of dilution. Dilution with bicarbonate ion-containing solutions reduced the change in isoelectric point in comparison to dilution with deionized water. The change in isoelectric point was inversely related to the concentration of bicarbonate ion in the diluting solution. The increase in isoelectric point observed following dilution with deionized water was reversed by the addition of bicarbonate ion. The observations suggest that carbonate ions occupying potential determining sites in the primary particles are in equilibrium with carbonate/bicarbonate ions in solution. Formulation or processing factors which affect the equilibrium will affect the isoelectric point of aluminum hydroxycarbonate suspensions and will influence their physical properties. 相似文献
995.
Lead Zirconate Titanate Hollow-Sphere Transducers 总被引:1,自引:0,他引:1
Richard Meyer Jr. Holger Weitzing Qichang Xu Qiming Zhang Robert E. Newnham Joe K. Cochran 《Journal of the American Ceramic Society》1994,77(6):1669-1672
Millimeter-sized, hollow spheres of lead zirconate titanate were fabricated by blowing gas through a fine-grained slurry of PZT-5. After they were sintered, the spheres were poled in two ways: radially between inside and outside electrodes, and tangentially between two outside electrodes. The capacitance and vibration modes were modeled and measured for these two poling configurations. The two principal modes of vibration were a breathing mode near 700 kHz and a wall thickness mode near 10 MHz. These spheres have potential uses in medical ultrasound, nondestructive testing, and low-density transducer arrays. 相似文献
996.
997.
Joe S. Busch Howard L. Julien John S. Ritchie David L. Watson 《Nuclear Engineering and Design》1982,67(3):317-326
Spent nuclear fuel assemblies stored in bedded salt can be modeled with a large array of dimensioned decay heat sources (spent fuel assemblies) in an extended thermal conducting media. Although a finite-difference or finite-element representation of the total storage facility could be established, regions of the repository should be analyzed separately since a model of the total repository would require formidable digital computing capacity. This paper explains the basis for thermally analyzing the total storage facility with separate models for the stored fuel assembly package and the salt medium. In addition, the effect of fuel assembly packaging on the maximum fuel temperature, the related problems of fuel handling prior to storage, and uncoupling of the effects of mine ventilation and conduction in the salt medium are discussed. 相似文献
998.
999.
Joe T. Darden 《Journal of Urban Affairs》1984,6(1):29-52
American Indian or Native American residential segregation is viewed within the general framework of ecological theory. According to theorists of human ecology, variation in segregation between groups relates directly to measurable differences on social and economic variables. This study uses 1980 census tract data and the index of dissimilarity to measure the extent of residential segregation in Michigan's 12 Standard Metropolitan Statistical Areas. Correlation coefficients were computed to assess whether a strong relationship exists between the residential segregation of American Indians and the spatial distribution of housing value and rent. The findings revealed that Indian-white residential segregation is lower than black-white segregation and that American Indians are more segregated from blacks than from whites. The segregated distribution pattern of American Indians is not strongly related to the cost of housing. 相似文献
1000.
Joe Schofield 《Information Systems Management》2003,20(1):82-85
Ants and people, ant work and software engineering; they are not as unrelated as one might think. Perhaps the ideas in this article provide an antidote for your organization or project; or perhaps the challenges presented in this article that confront software projects are the antithesis of your own organization, and you do not anticipate any immediate changes. Regardless of the outcome, you now have another context in which to examine the people and productivity in your organization. Do not be too surprised if you pay closer attention the next time you pass an ant hill. 相似文献