Anodization of AZ91D magnesium alloy in the electrolyte solution of 0.5 mol/L of sodium silicate and 1.0 mol/L of potassium fluoride was investigated. The anodic films were characterized using optical microscopy (OM...Anodization of AZ91D magnesium alloy in the electrolyte solution of 0.5 mol/L of sodium silicate and 1.0 mol/L of potassium fluoride was investigated. The anodic films were characterized using optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The corrosion resistance of the various anodized alloys was evaluated by a fast corrosion test using the solution of hydrochloric acid and potassium dichromate. The results showed that the addition of KF resulted in the presence of NaF in the anodic film. The thickness of the anodic film formed under a constant current density of 20 mA/cm^2 for 16 rain at 60℃ exceeded 100 gm. The growth of the anodic film could be divided into three stages based on the anodizing time; the growth rate was much faster during stage Ⅱ than in stages I and Ⅲ. The anodic film exhibited the highest corrosion resistance for the AZ91 alloy, which is attributed to the fact that the anodization was maintained until the end of stage Ⅱ.展开更多
We report on the single crystal growth and superconducting properties of PbTaSe2 with the non-centrosymmetric crystal structure. By using the chemicM vapor transport technique, centimeter-size single crystals are succ...We report on the single crystal growth and superconducting properties of PbTaSe2 with the non-centrosymmetric crystal structure. By using the chemicM vapor transport technique, centimeter-size single crystals are success- fully obtained. The measurement of temperature dependence of electricaJ resistivity p(T) in both normal and superconducting states indicates a quasi-two-dimensional electronic state in contrast to that of polycrystalline samples. Specific heat C(T) measurement reveals a bulk superconductivity with Tc ≈ 3.75K and a specific heat jump ratio of 1.42. All these results are in agreement with a moderately electron-phonon coupled, type-g Bardeen-Cooper-Schrieffer superconductor.展开更多
CaN nanorods are successfully fabricated by adjusting the flow rate ratio of hydrogen (H2)/nitrogen (N2) and growth temperature of the selective area growth (SAG) method with metal organic chemical vapor deposit...CaN nanorods are successfully fabricated by adjusting the flow rate ratio of hydrogen (H2)/nitrogen (N2) and growth temperature of the selective area growth (SAG) method with metal organic chemical vapor deposition (MOCVD). The SAG template is obtained by nanospherical-lens photolithography. It is found that increasing the flow rate of 1-12 will change the CaN crystal shape from pyramid to vertical rod, while increasing the growth temperature will reduce the diameters of GaN rods to nanometer scale. Finally the CaN nanorods with smooth lateral surface and relatively good quality are obtained under the condition that the H2:N2 ratio is 1:1 and the growth temperature is 1030℃. The good crystal quality and orientation of GaN nanorods are confirmed by high resolution transmission electron microscopy. The cathodoluminescence spectrum suggests that the crystal and optical quality is also improved with increasing the temperature.展开更多
InAs1-xSbx with different compositions is grown by molecular beam epitaxy on (100)-oriented semi-insulating GaAs substrates. The increase of Sb content in the epilayer results in the deterioration of crystal quality...InAs1-xSbx with different compositions is grown by molecular beam epitaxy on (100)-oriented semi-insulating GaAs substrates. The increase of Sb content in the epilayer results in the deterioration of crystal quality and surface morphology. Hall measurements show that the carrier concentration increases with the composition of Sb. The electron mobility decreases initially, when Sb composition exceeds a certain value, and the mobility increases slightly. In this work, we emphasize the comparison of crystal quality, surface morphology and electrical properties of epilayers with different Sb compositions.展开更多
We report the growth of InSb layers directly on GaAs (001) substrates without any buffer layers by molecular beam epitaxy (MBE). Influences of growth temperature and V/Ⅲ flux ratios on the crystal quality, the su...We report the growth of InSb layers directly on GaAs (001) substrates without any buffer layers by molecular beam epitaxy (MBE). Influences of growth temperature and V/Ⅲ flux ratios on the crystal quality, the surface morphology and the electrical properties of InSb thin films are investigated. The InSb samples with room- temperature mobility of 44600cm2/Vs are grown under optimized growth conditions. The effect of defects in InSb epitaxial on the electrical properties is researched, and we infer that the formation of In vacancy (VIn) and Sb anti-site (SbIn) defects is the main reason for concentrations changing with growth temperature and Sb2/In flux ratios. The mobility of the InSb sample as a function of temperature ranging from 90 K to 360K is demonstrated and the dislocation scattering mechanism and phonon scattering mechanism are discussed.展开更多
[Objective] The paper aims to study the relationship between genetic polymorphisms of three gene loci and growth character of Haimen Goats to provide reference to promote Haimen Goat growth character and cultivate Hai...[Objective] The paper aims to study the relationship between genetic polymorphisms of three gene loci and growth character of Haimen Goats to provide reference to promote Haimen Goat growth character and cultivate Haimen Goat new strain of fast-growth.[Method] We processed analysis and related statistical analysis on three gene loci of Haimen Goats with PCR-RFLP and PCR-SSCP.[Result] The results suggested that there were two genotypes in MSTN gene IntronⅡ,GH gene exonⅠ and GH gene exonⅡ in Haimen Goats.Different genotypes of these gene loci had different effects on relative growth character of Haimen Goats.[Conclusion] This study had a significant meaning about promoting Haimen Goat avoirdupois by marker assistant option.展开更多
The growth character and microstructure of high-T_c supereonducting YBCO thin films deposited on vari- ous substrates have been studied by X-ray diffraction, TEM and SEM.The results show that when the substrate temper...The growth character and microstructure of high-T_c supereonducting YBCO thin films deposited on vari- ous substrates have been studied by X-ray diffraction, TEM and SEM.The results show that when the substrate temperaturc is around 700~800℃ the films have a highly oriented texture with c-axis pependicular to the substrate. The structure of the single crystalline YBCO films grown epitaxially at optimal substrate tem- perature of 800℃ has been established by X-ray diffraction using Seemann-Bohlin geometry (SB). Brentano-Bragg geometry(BB),transmission Laue method and TEM. The lattice matching required for epitaxial growth is achievcd by azimuthal adjustment of the film plane with respect to the substrate plane. The sperior growth is demonstrated by film properties such as critical current density(2.4×10~6 A /cm^2,3.4× 10~6 A/cm^2 and 4.7×l0~6 A/cm^2) for films deposited on YSZ[(Zr(Y)O_2],SrTiO_3 and LaAIO_3 respectively at 77 K and zero fie1d.展开更多
A study was conducted to determine the genetic diversity of 39 determinate and indeterminate tomato inbred lines collected from China, Japan, S. Korea, and USA. Using 35 SSR polymorphic markers, a total of 150 alleles...A study was conducted to determine the genetic diversity of 39 determinate and indeterminate tomato inbred lines collected from China, Japan, S. Korea, and USA. Using 35 SSR polymorphic markers, a total of 150 alleles were found with moderate levels of diversity, and a high number of unique alleles existing in these tomato lines. The mean number of alleles per locus was 4.3 and the average polymorphism information content (PIC) was 0.31. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) clustering at genetic similarity value of 0.85 grouped the inbred lines into four groups, where one USA cultivar formed a separate and more distant cluster. The most similar inbred lines are from USA, both with determinate type, whereas the most different lines are from USA (Us-16) and Japan (Ja-2) with determinate and indeterminate growth habit, respectively. Clustering was consistent with the known information regarding geographical location and growth habit. The genetic distance information reported in this study might be used by breeders when planning future crosses among these inbred lines.展开更多
The growth parameters affecting the deposition of self-assembled InAs quantum dots (QDs) on GaAs substrate by low-pressure metal-organic chemical vapor deposition (MOCVD) are reported. The low-density InAs QDs (-...The growth parameters affecting the deposition of self-assembled InAs quantum dots (QDs) on GaAs substrate by low-pressure metal-organic chemical vapor deposition (MOCVD) are reported. The low-density InAs QDs (- 5 × 10^8cm^-2) are achieved using high growth temperature and low InAs coverage. Photoluminescence (PL) measurements show the good optical quality of low-density QDs. At room temperature, the ground state peak wavelength of PL spectrum and full-width at half-maximum (FWHM) are 1361 nm and 23 meV (35 nm), respectively, which are obtained as the GaAs capping layer grown using triethylgallium (TEG) and tertiallybutylarsine (TBA). The PL spectra exhibit three emission peaks at 1361, 1280, and 1204 nm, which correspond to the ground state, the first excited state, and the second excited state of the ODs, respectively.展开更多
The proliferation of vascular smooth muscle cells (VSMC) plays a role in the maintenance of hypertension and atherosclerosis. Diadenosine polyphosphates have been identified as modulators of the cardiovascular system....The proliferation of vascular smooth muscle cells (VSMC) plays a role in the maintenance of hypertension and atherosclerosis. Diadenosine polyphosphates have been identified as modulators of the cardiovascular system. We detected the existence of diadenosine polyphosphates in the heart and studied their growth stimulating effect on VSMC. Porcine cardiac tissue was deproteinated with perchloric acid and concentrated with a preparative reversed phase C18 column. Then the extract was separated with a size exclusion column, an anion exchange column, and an affinity column. It was then chromatographed with an anion exchange HPLC and a reversed phase HPLC and a purified substance was obtained. Med. Klinik I, Nephrol. Labor, Univ. Klinik Marien hospital, University of Bochum, Herne, Germany (Luo JK, Wang H, Schlüter H, JankowskifJ, Potthoff W, Tepel M and Zidek W) Using the BrdU method, this substance was shown to have a growth stimulating effect that is dose-dependent on VSMC. Matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) analysis showed that the molecular mass of the substance was 757.0, the same as diadenosine triphosphate (AP 3A). UV spectrum indicated the maximum absorption at 259 nm, similar to that of adenosine. Postsource decay (PSD) MALDI MS showed that the substance contained adenine, adenosine, AMP, ADP, and ATP, respectively. Enzymatic cleavage revealed that phosphates in this molecule connected adenosine in 5' position. It was determined from the above data that the substance was Ap 3A. In this study the existence of Ap 3A was demonstrated in the heart. It has a growth stimulating effect on VSMC.展开更多
The nanosize grain growth characteristics of spherical single-crystal titanium oxide (TiO2) during the rapid gaseous detonation reaction are discussed. Based on the experimental conditions and the Chapman-Jouguet th...The nanosize grain growth characteristics of spherical single-crystal titanium oxide (TiO2) during the rapid gaseous detonation reaction are discussed. Based on the experimental conditions and the Chapman-Jouguet theory, the Kruis model was introduced to simulate the growth characteristics of spherical TiO2 nanoparticles obtained under high pressure, high temperature and by rapid reaction. The results show that the numerical analysis can satisfactorily predict the growth characteristics of spherical TiO2 nanoparticles with diameters of 15-300 nm at different affecting factors, such as concentration of particles, reaction temperature and time, which are in agreement with the obtained experimental results. We found that the increase of the gas-phase reaction temperature, time, and particle concentration affects the growth tendency of spherical nanocrystal TiO2, which provides effective theoretical support for the controllable synthesis of multi-scale nanoparticles.展开更多
基金The work was financially supported by the National Natural Science Foundation of China (No.50541003) and the Aeronautic ScienceFoundation of China (No.04H51002).
文摘Anodization of AZ91D magnesium alloy in the electrolyte solution of 0.5 mol/L of sodium silicate and 1.0 mol/L of potassium fluoride was investigated. The anodic films were characterized using optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The corrosion resistance of the various anodized alloys was evaluated by a fast corrosion test using the solution of hydrochloric acid and potassium dichromate. The results showed that the addition of KF resulted in the presence of NaF in the anodic film. The thickness of the anodic film formed under a constant current density of 20 mA/cm^2 for 16 rain at 60℃ exceeded 100 gm. The growth of the anodic film could be divided into three stages based on the anodizing time; the growth rate was much faster during stage Ⅱ than in stages I and Ⅲ. The anodic film exhibited the highest corrosion resistance for the AZ91 alloy, which is attributed to the fact that the anodization was maintained until the end of stage Ⅱ.
基金Supported by the National Basic Research Program of China under Grant Nos 2015CB921303,2011CBA00100 and 2012CB821404the Strategic Priority Research Program(B) of Chinese Academy of Sciences under Grant Nos XDB07020100and XDB07020200the National Natural Science Foundation of China under Grant No 11174350
文摘We report on the single crystal growth and superconducting properties of PbTaSe2 with the non-centrosymmetric crystal structure. By using the chemicM vapor transport technique, centimeter-size single crystals are success- fully obtained. The measurement of temperature dependence of electricaJ resistivity p(T) in both normal and superconducting states indicates a quasi-two-dimensional electronic state in contrast to that of polycrystalline samples. Specific heat C(T) measurement reveals a bulk superconductivity with Tc ≈ 3.75K and a specific heat jump ratio of 1.42. All these results are in agreement with a moderately electron-phonon coupled, type-g Bardeen-Cooper-Schrieffer superconductor.
基金Supported by the Key Program of the National Natural Science Foundation of China under Grant No 61334009the National High Technology Research and Development Program of China under Grant No 2014AA032604
文摘CaN nanorods are successfully fabricated by adjusting the flow rate ratio of hydrogen (H2)/nitrogen (N2) and growth temperature of the selective area growth (SAG) method with metal organic chemical vapor deposition (MOCVD). The SAG template is obtained by nanospherical-lens photolithography. It is found that increasing the flow rate of 1-12 will change the CaN crystal shape from pyramid to vertical rod, while increasing the growth temperature will reduce the diameters of GaN rods to nanometer scale. Finally the CaN nanorods with smooth lateral surface and relatively good quality are obtained under the condition that the H2:N2 ratio is 1:1 and the growth temperature is 1030℃. The good crystal quality and orientation of GaN nanorods are confirmed by high resolution transmission electron microscopy. The cathodoluminescence spectrum suggests that the crystal and optical quality is also improved with increasing the temperature.
基金Supported by the Aeronautical Science Foundation of China under Grant No 20132435the National High-Technology Research and Development Program of China under Grant No 2013AA031903+1 种基金the National Natural Science Foundation of China under Grant Nos 61106013 and 61275107the China Postdoctoral Science Foundation under Grant No 2014M560936
文摘InAs1-xSbx with different compositions is grown by molecular beam epitaxy on (100)-oriented semi-insulating GaAs substrates. The increase of Sb content in the epilayer results in the deterioration of crystal quality and surface morphology. Hall measurements show that the carrier concentration increases with the composition of Sb. The electron mobility decreases initially, when Sb composition exceeds a certain value, and the mobility increases slightly. In this work, we emphasize the comparison of crystal quality, surface morphology and electrical properties of epilayers with different Sb compositions.
基金Supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences under Grant No 2015094the National Natural Science Foundation of China under Grant Nos 61204012,61274049 and 61376058+1 种基金the Beijing Natural Science Foundation under Grant Nos 4142053 and 4132070the Beijing Nova Program under Grant Nos 2010B056 and xxhz201503
文摘We report the growth of InSb layers directly on GaAs (001) substrates without any buffer layers by molecular beam epitaxy (MBE). Influences of growth temperature and V/Ⅲ flux ratios on the crystal quality, the surface morphology and the electrical properties of InSb thin films are investigated. The InSb samples with room- temperature mobility of 44600cm2/Vs are grown under optimized growth conditions. The effect of defects in InSb epitaxial on the electrical properties is researched, and we infer that the formation of In vacancy (VIn) and Sb anti-site (SbIn) defects is the main reason for concentrations changing with growth temperature and Sb2/In flux ratios. The mobility of the InSb sample as a function of temperature ranging from 90 K to 360K is demonstrated and the dislocation scattering mechanism and phonon scattering mechanism are discussed.
基金Supported by Agricultural High-tech Project of Jiangsu Province(BG2006304)~~
文摘[Objective] The paper aims to study the relationship between genetic polymorphisms of three gene loci and growth character of Haimen Goats to provide reference to promote Haimen Goat growth character and cultivate Haimen Goat new strain of fast-growth.[Method] We processed analysis and related statistical analysis on three gene loci of Haimen Goats with PCR-RFLP and PCR-SSCP.[Result] The results suggested that there were two genotypes in MSTN gene IntronⅡ,GH gene exonⅠ and GH gene exonⅡ in Haimen Goats.Different genotypes of these gene loci had different effects on relative growth character of Haimen Goats.[Conclusion] This study had a significant meaning about promoting Haimen Goat avoirdupois by marker assistant option.
文摘The growth character and microstructure of high-T_c supereonducting YBCO thin films deposited on vari- ous substrates have been studied by X-ray diffraction, TEM and SEM.The results show that when the substrate temperaturc is around 700~800℃ the films have a highly oriented texture with c-axis pependicular to the substrate. The structure of the single crystalline YBCO films grown epitaxially at optimal substrate tem- perature of 800℃ has been established by X-ray diffraction using Seemann-Bohlin geometry (SB). Brentano-Bragg geometry(BB),transmission Laue method and TEM. The lattice matching required for epitaxial growth is achievcd by azimuthal adjustment of the film plane with respect to the substrate plane. The sperior growth is demonstrated by film properties such as critical current density(2.4×10~6 A /cm^2,3.4× 10~6 A/cm^2 and 4.7×l0~6 A/cm^2) for films deposited on YSZ[(Zr(Y)O_2],SrTiO_3 and LaAIO_3 respectively at 77 K and zero fie1d.
文摘A study was conducted to determine the genetic diversity of 39 determinate and indeterminate tomato inbred lines collected from China, Japan, S. Korea, and USA. Using 35 SSR polymorphic markers, a total of 150 alleles were found with moderate levels of diversity, and a high number of unique alleles existing in these tomato lines. The mean number of alleles per locus was 4.3 and the average polymorphism information content (PIC) was 0.31. Unweighted Pair Group Method with Arithmetic Mean (UPGMA) clustering at genetic similarity value of 0.85 grouped the inbred lines into four groups, where one USA cultivar formed a separate and more distant cluster. The most similar inbred lines are from USA, both with determinate type, whereas the most different lines are from USA (Us-16) and Japan (Ja-2) with determinate and indeterminate growth habit, respectively. Clustering was consistent with the known information regarding geographical location and growth habit. The genetic distance information reported in this study might be used by breeders when planning future crosses among these inbred lines.
文摘The growth parameters affecting the deposition of self-assembled InAs quantum dots (QDs) on GaAs substrate by low-pressure metal-organic chemical vapor deposition (MOCVD) are reported. The low-density InAs QDs (- 5 × 10^8cm^-2) are achieved using high growth temperature and low InAs coverage. Photoluminescence (PL) measurements show the good optical quality of low-density QDs. At room temperature, the ground state peak wavelength of PL spectrum and full-width at half-maximum (FWHM) are 1361 nm and 23 meV (35 nm), respectively, which are obtained as the GaAs capping layer grown using triethylgallium (TEG) and tertiallybutylarsine (TBA). The PL spectra exhibit three emission peaks at 1361, 1280, and 1204 nm, which correspond to the ground state, the first excited state, and the second excited state of the ODs, respectively.
文摘The proliferation of vascular smooth muscle cells (VSMC) plays a role in the maintenance of hypertension and atherosclerosis. Diadenosine polyphosphates have been identified as modulators of the cardiovascular system. We detected the existence of diadenosine polyphosphates in the heart and studied their growth stimulating effect on VSMC. Porcine cardiac tissue was deproteinated with perchloric acid and concentrated with a preparative reversed phase C18 column. Then the extract was separated with a size exclusion column, an anion exchange column, and an affinity column. It was then chromatographed with an anion exchange HPLC and a reversed phase HPLC and a purified substance was obtained. Med. Klinik I, Nephrol. Labor, Univ. Klinik Marien hospital, University of Bochum, Herne, Germany (Luo JK, Wang H, Schlüter H, JankowskifJ, Potthoff W, Tepel M and Zidek W) Using the BrdU method, this substance was shown to have a growth stimulating effect that is dose-dependent on VSMC. Matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) analysis showed that the molecular mass of the substance was 757.0, the same as diadenosine triphosphate (AP 3A). UV spectrum indicated the maximum absorption at 259 nm, similar to that of adenosine. Postsource decay (PSD) MALDI MS showed that the substance contained adenine, adenosine, AMP, ADP, and ATP, respectively. Enzymatic cleavage revealed that phosphates in this molecule connected adenosine in 5' position. It was determined from the above data that the substance was Ap 3A. In this study the existence of Ap 3A was demonstrated in the heart. It has a growth stimulating effect on VSMC.
基金This research was financially supported by the Fundamental Research Funds for the Central Universities No. 2014QNA76, the Natural Science Foundation of Jiangsu Province No. BK20140178, the National Natural Science Foundation of China Nos. 11502282 and 41572263, the China Scholarship Council No.201506425040. Center of collaborative innovation in resource utilization and eco- logical restoration of the old industrial base. This is scientific research platform, temporarily with support number.
文摘The nanosize grain growth characteristics of spherical single-crystal titanium oxide (TiO2) during the rapid gaseous detonation reaction are discussed. Based on the experimental conditions and the Chapman-Jouguet theory, the Kruis model was introduced to simulate the growth characteristics of spherical TiO2 nanoparticles obtained under high pressure, high temperature and by rapid reaction. The results show that the numerical analysis can satisfactorily predict the growth characteristics of spherical TiO2 nanoparticles with diameters of 15-300 nm at different affecting factors, such as concentration of particles, reaction temperature and time, which are in agreement with the obtained experimental results. We found that the increase of the gas-phase reaction temperature, time, and particle concentration affects the growth tendency of spherical nanocrystal TiO2, which provides effective theoretical support for the controllable synthesis of multi-scale nanoparticles.