Based on the boundary condition of field engineering, numerical simulations of28 conditions of existing diffusers of 3 structure types were investigated by ComputationalFluid Dynamics software package, and there were ...Based on the boundary condition of field engineering, numerical simulations of28 conditions of existing diffusers of 3 structure types were investigated by ComputationalFluid Dynamics software package, and there were the problems of larger structure resistanceand lower diffusing efficiency of these diffusers by analysis of CFD results.Thestructure outlines of the energy-saving diffuser were constructed by the application ofstream function and potential function superimposing.On the basis of numerical simulationsof energy-saving diffusers of 5 area-enlarging ratios, structural resistances and diffusingefficiencies of 5 energy-saving diffusers were comparatively analyzed, and therange from 2.00 to 2.31 of the rational area-enlarging ratio of energy-saving diffusers wasderived.The optimization area-enlarging ratio of the energy-saving diffuser was presently2.28 through comparable analysis.From the above, the results show that the coefficient ofperformance of the energy-saving diffuser is better than 3 existing diffusers.展开更多
Information on forest structure is important for forest management decisions. This is inadequate in many situations, especially where timber is not of primary interest. We analyzed the structure of two forest types in...Information on forest structure is important for forest management decisions. This is inadequate in many situations, especially where timber is not of primary interest. We analyzed the structure of two forest types in the Oban Division of Cross River National Park, Nigeria. Systematic sampling technique was used to establish two transects measuring 2,000 x 2 m, at 600 m interval in the two forest types in four locations. Four 50 m x 50 m plots were located alternately at 500 m intervals along each transect, constituting 32 plots per forest type and 64 plots in all, Diameters at breast height （DBH）, base; middle and top; crown diameter; total height and crown length were measured on all trees with DBH 〉_ 10 cm. There were 159 stems/ha in the close-canopy forest and 132 stems/ha in the secondary forest. The mean DBH were 34.5 cm and 33.62 cm respectively. The mean heights were 24.79 m and 23.97 m, respectively. Basal area/ha were 41.59 m2 ha~ and 27.38 m2 hal for the two forest types. Majority of the trees encountered in the two forest types belonged to the middle stratum which has implication for small mammals＇ populations. Emergent trees which are otherwise scarce in other parts of the country were recorded, which also has implications for density thinning and seed supplies.展开更多
The elements of crop capacity structure of 13 summer characteristics in 33 winter wheat varieties, qualitative three-regularity and quantitative eight-regularity are investigated through the application of systematic ...The elements of crop capacity structure of 13 summer characteristics in 33 winter wheat varieties, qualitative three-regularity and quantitative eight-regularity are investigated through the application of systematic approach. The principle of triadness applied in a language, in a genetic code and other codes is used, i.e. the logic homology is employed. The purpose are （1） to show the use of a systematic approach to the analysis of elements of crop capacity structure of winter wheat; （2） to analyze efficiency, the years of harvests and winter hardiness; （3） to find the way of selection and varieties assessment in terms of the elements efficiency. The quantitative compatibility as the highest with the sign ＂＋＂ and the lowest with the sign ＂-＂ in terms of elements efficiency gives eight types of crop capacities. The type of crop capacity structure ＂＋＋＋＂ can serve as a full （higher） measure of a variety adaptableness and optimality of technologies. The triad of three characteristics as a type-＂＋＋＋＂ in which the first sign is the quantity of ears （QE）; the second is a quantity of grains （QG）; the third is the weight of grains （WG） creates the highest level of crop capacity.展开更多
The Sr3Tl5 phase was prepared by high temperature synthesis techniques through reaction of the high purity elements in the welded Nb tubes.The structure established through X-ray structural analysis shows the compound...The Sr3Tl5 phase was prepared by high temperature synthesis techniques through reaction of the high purity elements in the welded Nb tubes.The structure established through X-ray structural analysis shows the compound is a good hypoelectronic trielide example of the Pu3Pd5 structural type in which skeletal electron count is lower than in a traditional Zintl phase(Cmcm,Z = 4;a = 10.604(2) ,b = 8.675(2) ,and c = 10.985(2) ;V = 1010.5(3) 3).The strontium size and the compound's polarity appear responsible for this thallium phase crystallization in the Pu3Pd5 family type rather than the isoelectronic Sr3In5 version.A first-principle electronic structure calculation(LMTO) demonstrates that the strontium atoms participate substantially in Sr-Tl bonding in the structure.展开更多
基金Supported by the National Natural Science Foundation of China(50974060)the Scientific Research Fund of Hunan Provincial Education Department(09CY014)the Doctoral Fund of Hunan University of Science and Technology
文摘Based on the boundary condition of field engineering, numerical simulations of28 conditions of existing diffusers of 3 structure types were investigated by ComputationalFluid Dynamics software package, and there were the problems of larger structure resistanceand lower diffusing efficiency of these diffusers by analysis of CFD results.Thestructure outlines of the energy-saving diffuser were constructed by the application ofstream function and potential function superimposing.On the basis of numerical simulationsof energy-saving diffusers of 5 area-enlarging ratios, structural resistances and diffusingefficiencies of 5 energy-saving diffusers were comparatively analyzed, and therange from 2.00 to 2.31 of the rational area-enlarging ratio of energy-saving diffusers wasderived.The optimization area-enlarging ratio of the energy-saving diffuser was presently2.28 through comparable analysis.From the above, the results show that the coefficient ofperformance of the energy-saving diffuser is better than 3 existing diffusers.
文摘Information on forest structure is important for forest management decisions. This is inadequate in many situations, especially where timber is not of primary interest. We analyzed the structure of two forest types in the Oban Division of Cross River National Park, Nigeria. Systematic sampling technique was used to establish two transects measuring 2,000 x 2 m, at 600 m interval in the two forest types in four locations. Four 50 m x 50 m plots were located alternately at 500 m intervals along each transect, constituting 32 plots per forest type and 64 plots in all, Diameters at breast height （DBH）, base; middle and top; crown diameter; total height and crown length were measured on all trees with DBH 〉_ 10 cm. There were 159 stems/ha in the close-canopy forest and 132 stems/ha in the secondary forest. The mean DBH were 34.5 cm and 33.62 cm respectively. The mean heights were 24.79 m and 23.97 m, respectively. Basal area/ha were 41.59 m2 ha~ and 27.38 m2 hal for the two forest types. Majority of the trees encountered in the two forest types belonged to the middle stratum which has implication for small mammals＇ populations. Emergent trees which are otherwise scarce in other parts of the country were recorded, which also has implications for density thinning and seed supplies.
文摘The elements of crop capacity structure of 13 summer characteristics in 33 winter wheat varieties, qualitative three-regularity and quantitative eight-regularity are investigated through the application of systematic approach. The principle of triadness applied in a language, in a genetic code and other codes is used, i.e. the logic homology is employed. The purpose are （1） to show the use of a systematic approach to the analysis of elements of crop capacity structure of winter wheat; （2） to analyze efficiency, the years of harvests and winter hardiness; （3） to find the way of selection and varieties assessment in terms of the elements efficiency. The quantitative compatibility as the highest with the sign ＂＋＂ and the lowest with the sign ＂-＂ in terms of elements efficiency gives eight types of crop capacities. The type of crop capacity structure ＂＋＋＋＂ can serve as a full （higher） measure of a variety adaptableness and optimality of technologies. The triad of three characteristics as a type-＂＋＋＋＂ in which the first sign is the quantity of ears （QE）; the second is a quantity of grains （QG）; the third is the weight of grains （WG） creates the highest level of crop capacity.
基金supporting (by his DOE grant DE-AC02-07CH11358) the visit of J. C. Dai to Ames Laboratory, where principal part of this research was carried outthe National Natural Science Foundation of China (50971063)+1 种基金the Natural Science Foundation of Fujian Province of China (2010J01042 & 2011J01047)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry of China for supporting
文摘The Sr3Tl5 phase was prepared by high temperature synthesis techniques through reaction of the high purity elements in the welded Nb tubes.The structure established through X-ray structural analysis shows the compound is a good hypoelectronic trielide example of the Pu3Pd5 structural type in which skeletal electron count is lower than in a traditional Zintl phase(Cmcm,Z = 4;a = 10.604(2) ,b = 8.675(2) ,and c = 10.985(2) ;V = 1010.5(3) 3).The strontium size and the compound's polarity appear responsible for this thallium phase crystallization in the Pu3Pd5 family type rather than the isoelectronic Sr3In5 version.A first-principle electronic structure calculation(LMTO) demonstrates that the strontium atoms participate substantially in Sr-Tl bonding in the structure.
