Four diets were formulated to study the influence of varying crude protein levels on the performance, egg quality, serum and haematological characteristics at the first phase of laying cycle of sixty Bovan Nera laying...Four diets were formulated to study the influence of varying crude protein levels on the performance, egg quality, serum and haematological characteristics at the first phase of laying cycle of sixty Bovan Nera laying birds that were randomly allotted to dietary treatments. The four experimental diets had five replicates each and three birds per repli-cate. Diet 1 contained 14% crude protein (CP), while diet 2 contained 15% CP, diets 3 and 4 contained 16% and 17% CP respectively. The experimental birds were fed for 10 weeks and the data collected were statistically analysed. Apparent variations recorded for all the performance characteristics such as Egg number, Hen-day production, Feed Conversion Ratio (FCR) and weight gain were significantly different (p < 0.05). The best FCR value were recorded by birds fed 17% CP (3.45), while the highest weight gain mean value were also recorded by birds fed 17% CP value. Findings indicated a direct relationship between dietary crude protein values and performance.展开更多
The strain and electron energy levels of InAs/GaAs(001) quantum dots (QDs) with a GaNAs strain compensation layer (SCL) are investigated. The results show that both the hydrostatic and biaxiai strain inside the ...The strain and electron energy levels of InAs/GaAs(001) quantum dots (QDs) with a GaNAs strain compensation layer (SCL) are investigated. The results show that both the hydrostatic and biaxiai strain inside the QDs with a GaNAs SCL are reduced compared with those with GaAs capping layers. Moreover, most of the compressive strain in the growth surface is compensated by the tensile strain of the GaNAs SCL, which implies that the influence of the strain environment of underlying QDs upon the next-layer QDs' growth surface is weak and suggests that the homogeneity and density of QDs can be improved. Our results are consistent with the published experimental literature. A GaNAs SCL is shown to influence the strain and band edge. As is known, the strain and the band offset affect the electronic structure, which shows that the SCL is proved to be useful to tailor the emission wavelength of QDs. Our research helps to better understand how the strain compensation technology can be applied to the growth of stacked QDs, which are useful in solar cells and laser devices.展开更多
This paper investigates the structural upgrade of China's commodity trade over the past two decades from the perspectives of commodity categories, technical value-added and quality level. Based on the analysis of ...This paper investigates the structural upgrade of China's commodity trade over the past two decades from the perspectives of commodity categories, technical value-added and quality level. Based on the analysis of commodity categories, technical value-added and quality, this paper arrives at the following findings: High technology manufactures accounted for a growing share of China's commodity export, the overall technical level of Chinese exports significantly upgraded, and most of Chinese commodities upgraded from low quality to medium-and high-quality levels. As can be seen from the structure of China's bilateral trade with its five major trading partners, China's exporting goods remained inferior to importing goods in terms of technology and quality despite their quality upgrades.展开更多
文摘Four diets were formulated to study the influence of varying crude protein levels on the performance, egg quality, serum and haematological characteristics at the first phase of laying cycle of sixty Bovan Nera laying birds that were randomly allotted to dietary treatments. The four experimental diets had five replicates each and three birds per repli-cate. Diet 1 contained 14% crude protein (CP), while diet 2 contained 15% CP, diets 3 and 4 contained 16% and 17% CP respectively. The experimental birds were fed for 10 weeks and the data collected were statistically analysed. Apparent variations recorded for all the performance characteristics such as Egg number, Hen-day production, Feed Conversion Ratio (FCR) and weight gain were significantly different (p < 0.05). The best FCR value were recorded by birds fed 17% CP (3.45), while the highest weight gain mean value were also recorded by birds fed 17% CP value. Findings indicated a direct relationship between dietary crude protein values and performance.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60908028, 60971068, 10979065, and 61275201)the Fundamental Research Funds for the Central Universities of Ministry of Education of China (Grant No. 2011RC0402)the Program for New Century Excellent Talents in University of Ministry of Education of China (Grant No. NCET-10-0261)
文摘The strain and electron energy levels of InAs/GaAs(001) quantum dots (QDs) with a GaNAs strain compensation layer (SCL) are investigated. The results show that both the hydrostatic and biaxiai strain inside the QDs with a GaNAs SCL are reduced compared with those with GaAs capping layers. Moreover, most of the compressive strain in the growth surface is compensated by the tensile strain of the GaNAs SCL, which implies that the influence of the strain environment of underlying QDs upon the next-layer QDs' growth surface is weak and suggests that the homogeneity and density of QDs can be improved. Our results are consistent with the published experimental literature. A GaNAs SCL is shown to influence the strain and band edge. As is known, the strain and the band offset affect the electronic structure, which shows that the SCL is proved to be useful to tailor the emission wavelength of QDs. Our research helps to better understand how the strain compensation technology can be applied to the growth of stacked QDs, which are useful in solar cells and laser devices.
基金supported by Shanghai Municipal Philosophical and Social Science Planning General Program(2017BJL005)
文摘This paper investigates the structural upgrade of China's commodity trade over the past two decades from the perspectives of commodity categories, technical value-added and quality level. Based on the analysis of commodity categories, technical value-added and quality, this paper arrives at the following findings: High technology manufactures accounted for a growing share of China's commodity export, the overall technical level of Chinese exports significantly upgraded, and most of Chinese commodities upgraded from low quality to medium-and high-quality levels. As can be seen from the structure of China's bilateral trade with its five major trading partners, China's exporting goods remained inferior to importing goods in terms of technology and quality despite their quality upgrades.