To reveal the complicated mechanism of the multicomponent mass transfer during the growth of ternary compound semiconductors, a numerical model based on Maxwell-Stefan equations was developed to simulate the Bridgman ...To reveal the complicated mechanism of the multicomponent mass transfer during the growth of ternary compound semiconductors, a numerical model based on Maxwell-Stefan equations was developed to simulate the Bridgman growth of CdZnTe crystal. The Maxwell-Stefan diffusion coefficients in the melt were estimated. Distributions of Zn, Cd, and Te were calculated with variable ampoule traveling rate and diffusion coefficients. The experimental results show that Zn in melt near the growth interface decreases and diffuses from the bulk melt to the growth interface. For Cd, the situation is just the opposite. The coupling effects of Zn and Cd diffusions result in an uphill diffusion of Te at the beginning of the growth. Throughout the growth, the concentration of Te in the melt keeps low near the growth interface but high far from the growth interface. Increasing the ampoule traveling rate will aggravate the segregation of Zn and Cd, and hence deteriorate the uniformity of Te. We also find that not only the diffusion coefficients but also the ratios between them have significant influence on the species diffusions.展开更多
The following equation is proposed in this paper to estimate the crustal growth rate of the North China Platform on the basis of mass equilibrium between the crust and the mantle:The results indicate that the mass fra...The following equation is proposed in this paper to estimate the crustal growth rate of the North China Platform on the basis of mass equilibrium between the crust and the mantle:The results indicate that the mass fractions of the crust during different geological periods are close to the real mass fractions of the crust in the upper mantle and the whole mantle (2-2.5% and 0.5 -0.6%, respectively, Hofmann, 1986), and the discrepancy of the results is probably related to that the heterogeneous contribution of the mantle to the crust both in space and in element. The results also show that the mass of the Archaean crust is only half that of the Proterozoic crust, and the crustal mass remained unchanged from Proterozoic to Paleozoic. suggesting that the plate movement at least started from the Late Proterozoic.展开更多
The origin of a seed strongly impacts its traits, and both origin and seed traits influence seed germination and seedling development. However, in many instances, this effect on the seedling does not persist into adul...The origin of a seed strongly impacts its traits, and both origin and seed traits influence seed germination and seedling development. However, in many instances, this effect on the seedling does not persist into adulthood, and little is known about how seed traits and original environment affect seedling/tree growth over time. In this study, seed size, seed mass, seedling/tree growth and origins were collected and determined for 23 provenances of Quercus acutissima from across China. Origin variables correlated well with seed size and seed mass. In stepwise multiple regressions, a longitudinal aridity index explained 49.2-68.7% of the total variation in seed size and mass, while only seed width was correlated with seedling/tree height (H) and diameter at the ground (D) from seed traits and origins. The total variance in H and D explained by the models decreased over time, for example, the R <sup>2</sup> value of the models for H declined from 0.477 in the first year to 0.224 in the fourth year; no models was significant in the fifth year. These results indicate that seed size, regulated by the longitudinal aridity index strongly impacted seedling and tree growth, but the strength of the influence decreased over time, and disappeared after 4 years.展开更多
目的:分析不同体重指数(body mass index,BMI)的特发性矮小症(idiopathic short stature,ISS)患儿在重组人生长激素(recombinant human growth hormone,rhGH)治疗下的疗效差异及安全性。方法:选取于河北北方学院附属第一医院接受rhGH治...目的:分析不同体重指数(body mass index,BMI)的特发性矮小症(idiopathic short stature,ISS)患儿在重组人生长激素(recombinant human growth hormone,rhGH)治疗下的疗效差异及安全性。方法:选取于河北北方学院附属第一医院接受rhGH治疗的ISS患儿为研究对象,根据7岁以下儿童生长标准及中国6~18岁学龄儿童青少年性别、年龄、体质指数、超重与肥胖界值,将ISS患儿分为BMI正常组、超重组、肥胖组,测定三组患儿治疗前、治疗3个月及6个月后的身高(height,Ht)、BMI、生长速率(growth velocity,GV)、身高标准差积分(height standard deviation score,HtSDS)、胰岛素样生长因子-1(insulin like growth factor-1,IGF-1)、胰岛素样生长因子结合蛋白-3(insulin like growth factor binding-protein-3,IGFBP-3)、空腹血糖(fasting blood glucose,FBG)、甲状腺功能及肝功能。结果:三组ISS患儿在rhGH治疗后Ht、GV、HtSDS、IGF-1、IGFBP-3均较治疗前增加(P<0.05)。BMI正常组患儿Ht、GV和HtSDS增长量明显高于超重组及肥胖组(P<0.05),超重组与肥胖组相比无明显差异(P>0.05)。BMI正常组患儿在治疗6个月后BMI较治疗前增加(P<0.05),而超重组及肥胖组BMI均较前下降(P<0.05)。rhGH治疗对FBG、甲状腺功能、肝功能无明显影响。结论:rhGH能明显提高ISS患儿的Ht、HtSDS、GV、IGF-1、IGFBP-3水平,BMI正常的ISS患儿的疗效明显好于超重组及肥胖组,超重及肥胖ISS患儿疗效无明显差异,rhGH治疗具有较好的安全性。展开更多
基金Funded by the National Key R&D Program of China(2016YFB0402405,2016YFF0101301)the Special Fund of National Key Scientific Instruments and Equipments Development(2011YQ040082)+4 种基金the National 973 Project of China(2011CB610400)the 111 Project of China(B08040)the National Natural Science Foundation of China(NNSFC-61274081,51372205,and 51502244)the Fundamental Research Funds for the Central Universities(3102015BJ(II)ZS014,G2016KY0104,3102016ZY011)the Research Fund of the State Key Laboratory of Solidification Processing(NWPU),China
文摘To reveal the complicated mechanism of the multicomponent mass transfer during the growth of ternary compound semiconductors, a numerical model based on Maxwell-Stefan equations was developed to simulate the Bridgman growth of CdZnTe crystal. The Maxwell-Stefan diffusion coefficients in the melt were estimated. Distributions of Zn, Cd, and Te were calculated with variable ampoule traveling rate and diffusion coefficients. The experimental results show that Zn in melt near the growth interface decreases and diffuses from the bulk melt to the growth interface. For Cd, the situation is just the opposite. The coupling effects of Zn and Cd diffusions result in an uphill diffusion of Te at the beginning of the growth. Throughout the growth, the concentration of Te in the melt keeps low near the growth interface but high far from the growth interface. Increasing the ampoule traveling rate will aggravate the segregation of Zn and Cd, and hence deteriorate the uniformity of Te. We also find that not only the diffusion coefficients but also the ratios between them have significant influence on the species diffusions.
文摘The following equation is proposed in this paper to estimate the crustal growth rate of the North China Platform on the basis of mass equilibrium between the crust and the mantle:The results indicate that the mass fractions of the crust during different geological periods are close to the real mass fractions of the crust in the upper mantle and the whole mantle (2-2.5% and 0.5 -0.6%, respectively, Hofmann, 1986), and the discrepancy of the results is probably related to that the heterogeneous contribution of the mantle to the crust both in space and in element. The results also show that the mass of the Archaean crust is only half that of the Proterozoic crust, and the crustal mass remained unchanged from Proterozoic to Paleozoic. suggesting that the plate movement at least started from the Late Proterozoic.
基金supported by the National Natural Science Foundation of China(No.31570583)the Lecture and Study Program for Outstanding Scholars from Home and Abroad(No.CAFYBB2011007)
文摘The origin of a seed strongly impacts its traits, and both origin and seed traits influence seed germination and seedling development. However, in many instances, this effect on the seedling does not persist into adulthood, and little is known about how seed traits and original environment affect seedling/tree growth over time. In this study, seed size, seed mass, seedling/tree growth and origins were collected and determined for 23 provenances of Quercus acutissima from across China. Origin variables correlated well with seed size and seed mass. In stepwise multiple regressions, a longitudinal aridity index explained 49.2-68.7% of the total variation in seed size and mass, while only seed width was correlated with seedling/tree height (H) and diameter at the ground (D) from seed traits and origins. The total variance in H and D explained by the models decreased over time, for example, the R <sup>2</sup> value of the models for H declined from 0.477 in the first year to 0.224 in the fourth year; no models was significant in the fifth year. These results indicate that seed size, regulated by the longitudinal aridity index strongly impacted seedling and tree growth, but the strength of the influence decreased over time, and disappeared after 4 years.
文摘目的:分析不同体重指数(body mass index,BMI)的特发性矮小症(idiopathic short stature,ISS)患儿在重组人生长激素(recombinant human growth hormone,rhGH)治疗下的疗效差异及安全性。方法:选取于河北北方学院附属第一医院接受rhGH治疗的ISS患儿为研究对象,根据7岁以下儿童生长标准及中国6~18岁学龄儿童青少年性别、年龄、体质指数、超重与肥胖界值,将ISS患儿分为BMI正常组、超重组、肥胖组,测定三组患儿治疗前、治疗3个月及6个月后的身高(height,Ht)、BMI、生长速率(growth velocity,GV)、身高标准差积分(height standard deviation score,HtSDS)、胰岛素样生长因子-1(insulin like growth factor-1,IGF-1)、胰岛素样生长因子结合蛋白-3(insulin like growth factor binding-protein-3,IGFBP-3)、空腹血糖(fasting blood glucose,FBG)、甲状腺功能及肝功能。结果:三组ISS患儿在rhGH治疗后Ht、GV、HtSDS、IGF-1、IGFBP-3均较治疗前增加(P<0.05)。BMI正常组患儿Ht、GV和HtSDS增长量明显高于超重组及肥胖组(P<0.05),超重组与肥胖组相比无明显差异(P>0.05)。BMI正常组患儿在治疗6个月后BMI较治疗前增加(P<0.05),而超重组及肥胖组BMI均较前下降(P<0.05)。rhGH治疗对FBG、甲状腺功能、肝功能无明显影响。结论:rhGH能明显提高ISS患儿的Ht、HtSDS、GV、IGF-1、IGFBP-3水平,BMI正常的ISS患儿的疗效明显好于超重组及肥胖组,超重及肥胖ISS患儿疗效无明显差异,rhGH治疗具有较好的安全性。
