利用扫描电镜、Image Pro Plus软件和Nano Measurer软件研究了微孔在铸态、固溶处理态和完全热处理态的一种三代镍基单晶高温合金中的形貌及尺寸,采用蠕变试验机研究了微孔在合金持久试验过程中的演化。结果表明:铸态合金枝晶间区域γ/...利用扫描电镜、Image Pro Plus软件和Nano Measurer软件研究了微孔在铸态、固溶处理态和完全热处理态的一种三代镍基单晶高温合金中的形貌及尺寸,采用蠕变试验机研究了微孔在合金持久试验过程中的演化。结果表明:铸态合金枝晶间区域γ/γ′共晶边缘存在少量的不规则形状的微孔,微孔的体积分数约为0.09%,平均尺寸约为9.54μm;经固溶处理后合金中会产生圆形和方形的固溶微孔,固溶处理(1325℃)时间由4 h延长到8 h,固溶微孔的体积分数由0.42%增加到0.46%,增加了约10%。时效处理对固溶微孔的体积分数没有明显影响。固溶微孔会在合金持久过程中发展为裂纹源,最终导致持久断裂,方形微孔更易发展成裂纹。展开更多
The direct electron transfer of hemoglobin at the PAMAM-MWNTs-AuNPs composite film modified glassy carbon electrode was studied. In a phosphate buffer solution(PBS, pH=7.0), the formal potential(E^0) of Hb was -0....The direct electron transfer of hemoglobin at the PAMAM-MWNTs-AuNPs composite film modified glassy carbon electrode was studied. In a phosphate buffer solution(PBS, pH=7.0), the formal potential(E^0) of Hb was -0.105 V versus SCE, the electron transfer rate constant was 4.66 s-1. E^0' of Hb at the modified electrode was linearly varied in a pH range of 5.0-8.0 with a slope of-49.2 mV/pH. The Hb/PAMAM-MWNTs-AuNPs/GCE gave an excellent electrocatalytic response to the reduction of hydrogen peroxide. The catalytic current increased linearly with H2O2 concentration in a range of 1.0× 10^-6 to 2.2× 10^-3 mol/L. The detection limit was 2.0× 10^-7 mol/L at a signal to noise ratio of 3. The Michaelis-Menten constant(Km^app) was 2.95 mmol/L.展开更多
[ Objective] The aim was to explore the classification basis of Chinese local chicken for providing theoretical basis of giving full play to the genetic potential, heterosis, new ideas and methods of new varieties and...[ Objective] The aim was to explore the classification basis of Chinese local chicken for providing theoretical basis of giving full play to the genetic potential, heterosis, new ideas and methods of new varieties and strains breeding, identification and evaluation. [ Method] The multivariate statistical analysis of laying performance and production area ecology of 11 kind of chicken was done by principal component analysis and cluster analysis. E]Result] The cluster analysis of 4 egg laying performance indexs indicated that 11 kinds of chicken can be roughly classified into large chicken and small chicken; 10 indexs of multivariate statistical analysis indicated that 11 kinds of chicken can be classified into high altitude type and low altitude type when first 3 eigenvalues were selected as 3 principal component by principal component analysis( 94.99% of the total amount of information), and similarity coefficient was computed according to first three principal component values of each kind and then cluster analysis was done with nearest neighbor way. [ Conclusion] Ecological factor was also an important aspect of assortment.展开更多
The Nei's improved genetic distance(DA)and gene flow(Nm)were measured using sixteen microsatellite markers.Dendograms based on DA genetic distance using the neighbor-joining(NJ)method and STRUCTURE program were co...The Nei's improved genetic distance(DA)and gene flow(Nm)were measured using sixteen microsatellite markers.Dendograms based on DA genetic distance using the neighbor-joining(NJ)method and STRUCTURE program were constructed to analyze the genetic structure and relationship among 10 Chinese indigenous chicken breeds.The results showed that dendograms of DA genetic distance using the NJ method divided the 10 chicken breeds into two main clusters;one consisted of breeds of low weight body(CHA,TTB,XIA,GUS and BAI),the other contained heavier breeds(LAN,DAG,YOU,XIS and LUY).In the lighter breeds,TIB and CHA clustered together,as did XIA and GUS.In the heavier breeds,XIS and LUY was clustered together in one branch,but LAN,DAG and YOU clustered in independent branches.The results were consistent with Nm estimates among the 10 indigenous chicken breeds.The STRUCTURE program properly inferred the presence of genetic structure despite not pre-defining the origin of individuals.The genetic cluster inferred by STRUCTURE was basically the same as that from the DA distance clustering method.An advantage of the STRUCTURE program was its ability to identify the migrants and admixed individuals in the 10 chicken populations;this could not be achieved by use of the DA distance clustering method.展开更多
GPAT,AIRC and purH genes are involved in the de novo purine biosynthesis,and they all had significant effects on muscle inosine monophosphate(IMP) content in chickens.This study was designed to investigate the effects...GPAT,AIRC and purH genes are involved in the de novo purine biosynthesis,and they all had significant effects on muscle inosine monophosphate(IMP) content in chickens.This study was designed to investigate the effects of GPAT,AIRC and purH genes on muscle IMP content in a relatively large population of Baier chickens;single genotype effects as well as the combined genotype effects were analyzed.The results further support that GPAT,AIRC and purH genes had effects on muscle IMP content;they might be candidate loci or linked to major genes affecting muscle IMP content.The combined genotypic effects were significantly higher than those of the single genotypes and were even larger when more gene loci were combined.We tentatively conclude that combined genotypes are superior to single genotypes as potential molecular markers for meat quality traits in chicken.展开更多
基金Supported by the National Natural Science Foundation of China(No.20605009)
文摘The direct electron transfer of hemoglobin at the PAMAM-MWNTs-AuNPs composite film modified glassy carbon electrode was studied. In a phosphate buffer solution(PBS, pH=7.0), the formal potential(E^0) of Hb was -0.105 V versus SCE, the electron transfer rate constant was 4.66 s-1. E^0' of Hb at the modified electrode was linearly varied in a pH range of 5.0-8.0 with a slope of-49.2 mV/pH. The Hb/PAMAM-MWNTs-AuNPs/GCE gave an excellent electrocatalytic response to the reduction of hydrogen peroxide. The catalytic current increased linearly with H2O2 concentration in a range of 1.0× 10^-6 to 2.2× 10^-3 mol/L. The detection limit was 2.0× 10^-7 mol/L at a signal to noise ratio of 3. The Michaelis-Menten constant(Km^app) was 2.95 mmol/L.
基金funded by the national"863"program(2011AA100305)Zhejiang Province Science and Technology Platform Project(2011E60003)+1 种基金Yangzhou City Science and Technology Plan(YZ2011069)Natural Science Foundation of Jiangsu Province(BK2011431)
文摘[ Objective] The aim was to explore the classification basis of Chinese local chicken for providing theoretical basis of giving full play to the genetic potential, heterosis, new ideas and methods of new varieties and strains breeding, identification and evaluation. [ Method] The multivariate statistical analysis of laying performance and production area ecology of 11 kind of chicken was done by principal component analysis and cluster analysis. E]Result] The cluster analysis of 4 egg laying performance indexs indicated that 11 kinds of chicken can be roughly classified into large chicken and small chicken; 10 indexs of multivariate statistical analysis indicated that 11 kinds of chicken can be classified into high altitude type and low altitude type when first 3 eigenvalues were selected as 3 principal component by principal component analysis( 94.99% of the total amount of information), and similarity coefficient was computed according to first three principal component values of each kind and then cluster analysis was done with nearest neighbor way. [ Conclusion] Ecological factor was also an important aspect of assortment.
基金supported by the Program of National Technological Basis from Ministry of Science and Technology of China(No.2005DKA21101)the National Natural Science Foundation of China(No.30700572)
文摘The Nei's improved genetic distance(DA)and gene flow(Nm)were measured using sixteen microsatellite markers.Dendograms based on DA genetic distance using the neighbor-joining(NJ)method and STRUCTURE program were constructed to analyze the genetic structure and relationship among 10 Chinese indigenous chicken breeds.The results showed that dendograms of DA genetic distance using the NJ method divided the 10 chicken breeds into two main clusters;one consisted of breeds of low weight body(CHA,TTB,XIA,GUS and BAI),the other contained heavier breeds(LAN,DAG,YOU,XIS and LUY).In the lighter breeds,TIB and CHA clustered together,as did XIA and GUS.In the heavier breeds,XIS and LUY was clustered together in one branch,but LAN,DAG and YOU clustered in independent branches.The results were consistent with Nm estimates among the 10 indigenous chicken breeds.The STRUCTURE program properly inferred the presence of genetic structure despite not pre-defining the origin of individuals.The genetic cluster inferred by STRUCTURE was basically the same as that from the DA distance clustering method.An advantage of the STRUCTURE program was its ability to identify the migrants and admixed individuals in the 10 chicken populations;this could not be achieved by use of the DA distance clustering method.
基金supported by the Earmarked Fund For Modern Agro-Industry Technology Research SystemNational High Technology Research and Development Program of P.R.China(No.863-2008AA101009-7), 863-2006AA10Z1D8+1 种基金National Key Technology R&D Program(No.2008BADB2B01)Key Technology R&D Program of Jiangsu Province(No.BE2008361)
文摘GPAT,AIRC and purH genes are involved in the de novo purine biosynthesis,and they all had significant effects on muscle inosine monophosphate(IMP) content in chickens.This study was designed to investigate the effects of GPAT,AIRC and purH genes on muscle IMP content in a relatively large population of Baier chickens;single genotype effects as well as the combined genotype effects were analyzed.The results further support that GPAT,AIRC and purH genes had effects on muscle IMP content;they might be candidate loci or linked to major genes affecting muscle IMP content.The combined genotypic effects were significantly higher than those of the single genotypes and were even larger when more gene loci were combined.We tentatively conclude that combined genotypes are superior to single genotypes as potential molecular markers for meat quality traits in chicken.