The calculation of earth pressure is a difficult problem in the pit foundation design. Aiming at the problem, the earth pressure calculation formulas considering the displacement are proposed. A method for determining...The calculation of earth pressure is a difficult problem in the pit foundation design. Aiming at the problem, the earth pressure calculation formulas considering the displacement are proposed. A method for determining the limit displacement is given and it is convenient for use. The result indicates that the earth pressure calculated by the formulas is between the earth pressure at rest and the Rankine earth pressure, the formulas can reflect the change rules of active and passive earth pressures along with the displacement. Moreover, the calculation result using the formulas is approximate to the monitoring result. It confirms the validity of the formula deduction and the rationality of the calculation results. As for the passive earth pressure, the calculation method is theoretically feasible.展开更多
Aim To determine and analyze fatty acids, amino acids and trace elements of Hirudinaria manillensis. Methods Contents of fatty acids, amino acids and trace elements were determined by GC/MS, HPLC and ICP-AES. Results ...Aim To determine and analyze fatty acids, amino acids and trace elements of Hirudinaria manillensis. Methods Contents of fatty acids, amino acids and trace elements were determined by GC/MS, HPLC and ICP-AES. Results H. manillensis contained sixteen fatty acids, among which the percentage of unsaturated fatty acids is 34.05%. The eighteen amino acids were detected, which included eight essential amino acids in human body with a ratio of 33.53 %. There were eight trace elements (Ca, Cr, Cu, Fe, Mg, Mn, V and Zn) from H. manillensis, and the content of Ca, Zn and Fe were apparently higher than those of other elements. Conclusion These methods are simple and accurate. This study reports routine quantitative methods for the analysis of multiple components in H. manillensis by GC/MS, HPLC and ICP-AES.展开更多
A new Ni-based superalloy Ni48Cr28W5Co3Mn1Si1.6 was developed and the influence of a trace amount of rare earth (RE) metal addition on the oxidation resistance of this alloy was investigated. Isothermal oxidation beha...A new Ni-based superalloy Ni48Cr28W5Co3Mn1Si1.6 was developed and the influence of a trace amount of rare earth (RE) metal addition on the oxidation resistance of this alloy was investigated. Isothermal oxidation behavior was investigated at 950?1150 °C in air, and then analyzed using scanning electronic microscopy and X-ray diffraction. The results showed that oxidation mass gain kinetics of the samples with and without RE elements follow the parabolic law. The effect of 0.20% RE on oxidation resistance is relatively small, and the oxidation rate constant of the alloy modified with 0.20% RE addition decreases by 5.9%?9.0%. Oxidation at 950?1150 °C for 100 h results in the formation of MnCr2O4, Cr2O3 and SiO2. A continuous and protective MnCr2O4 spinel layer forms as outer layer. The continuous middle oxide layer is confirmed to be Cr2O3, and the innermost layer consists of discontinuous SiO2.展开更多
The absorbing process in isolating and coating process of α-olefin drag reducing polymer was studied by molecular dynamic simulation method, on basis of coating theory of α-olefin drag reducing polymer particles wit...The absorbing process in isolating and coating process of α-olefin drag reducing polymer was studied by molecular dynamic simulation method, on basis of coating theory of α-olefin drag reducing polymer particles with polyurethane as coating material. The distributions of sodium laurate, sodium dodeeyl sulfate, and sodium dodeeyl benzene sulfonate on the surface of α-olefin drag reducing polymer particles were almost the same, but the bending degrees of them were obviously different. The bending degree of SLA molecules was greater than those of the other two surfactant molecules. Simulation results of absorbing and accumulating structure showed that, though hydrophobie properties of surfactant molecules were almost the same, water density around long chain sulfonate sodium was bigger than that around alkyl sulfate sodium. This property goes against useful absorbing and accumulating on the surface of α-olefin drag reducing polymer particles; simulation results of interactions of different surfactant and multiple hydroxyl compounds on surface of particles showed that, interactions of different surfaetant and one kind of multiple hydroxyl compound were similar to those of one kind of surfaetant and different multiple hydroxyl compounds. These two contrast types of interactions also exhibited the differences of absorbing distribution and closing degrees to surface of particles. The sequence of closing degrees was derived from simulation; control step of addition polymerization interaction in coating process was absorbing mass transfer process, so the more closed to surface of particle the multiple hydroxyl compounds were, the easier interactions With isoeyanate were. Simulation results represented the compatibility relationship between surfactant and multiple hydroxyl compounds. The isolating and coating processes of α-olefin drag reducing polymer were further understood on molecule and atom level through above simulation research, and based on the simulation, a referenced theoretical basis was provided for practical optimal selection and experimental preparation of α-olefin drag reducing polymer particles suspension isolation agent.展开更多
Neural stem cell is presently the research hotspot in neuroscience. Recent progress indicates that epigenetic modulation is closely related to the self-renewal and differentiation of neural stem cell. Epigenetics refe...Neural stem cell is presently the research hotspot in neuroscience. Recent progress indicates that epigenetic modulation is closely related to the self-renewal and differentiation of neural stem cell. Epigenetics refer to the study of mitotical/meiotical heritage changes in gene function that cannot be explained by changes in the DNA sequence. Major epigenetic mechanisms include DNA methylation, histone modification, chromatin remodeling, genomic imprinting, and non-coding RNA. In this review, we focus on the new insights into the epigenetic mechanism for neural stem cells fate.展开更多
The rollup and the drilldown are quite frequent based on dimension hierarchies in on-line analytical processing (OLAP), but prefixCube does not directly support dimension hierarchies. The PrefixCube is extended for ...The rollup and the drilldown are quite frequent based on dimension hierarchies in on-line analytical processing (OLAP), but prefixCube does not directly support dimension hierarchies. The PrefixCube is extended for incorporating hierarchical data cubes, i.e. cubes with hierarchical dimensions ,thus obtaining HierPrefixCube. HierPrefixCube retains advantages on computation and organization of PrefixCube, and it can directly support aggregate queries on levels of the dimension hierarchy.展开更多
Based on the analyses of the microstructures and phase diagrams of the TiAl-based alloy, the relationship among the composition, structure and mechanical properties of the B2-containing y-TiAI alloys was reviewed. The...Based on the analyses of the microstructures and phase diagrams of the TiAl-based alloy, the relationship among the composition, structure and mechanical properties of the B2-containing y-TiAI alloys was reviewed. The refinement of microstructures and improvement of mechanical properties of TiA1 alloy through stabilization of the β/B2 phase were reviewed. The mechanism of the superplastic behavior of the B2-containing y-TiAI alloys was discussed. With a reasonable addition of β-stabilizer, metastable B2 phase can be maintained, which is favorable for fine-grained structure and better high-temperature deformation behaviors. The mechanical properties of the B2-containing TiAI alloy, including the deformability and elevated temperature properties, can also be improved with doping elements and subsequent hot-working processes. The above mentioned researches discuss a new way for developing TiAI alloys with comprehensive properties, including good deformability and creep resistance.展开更多
Based on the Mg58.5Cu30.5Y11 alloy, 10% Ti, 10% Be and 10% Ti70Be30 (mole fraction) were respectively added to the alloy and samples with a diameter of 3 mm were fabricated by conventional Cu-mold casting method. Th...Based on the Mg58.5Cu30.5Y11 alloy, 10% Ti, 10% Be and 10% Ti70Be30 (mole fraction) were respectively added to the alloy and samples with a diameter of 3 mm were fabricated by conventional Cu-mold casting method. The phase constituent, thermal stability and microstructure of the alloys were investigated by using X-ray diffraction, differential scanning calorimetry and scanning electron microscopy, respectively. The effects of alloying elements Ti and Be on the microstructure and mechanical properties of Mg58.sCu3o.sYll alloy were discussed. The results show that CuTi phase is distributed in (Mg0.585Cu0.305Y0.11)90Ti10 and (Mg58.5Cu30.5Y11)90(Ti0.7Be0.3)10 alloys, while CuYBe glassy phase containing CuY crystals is embedded in the matrix of (Mg58.5Cu30.5Y11)90Be10 alloy. Under uniaxial compressive loading, the largest compressive fracture strengths for (Mg58.5Cu30.5Y11)90Ti10, (Mg58.5Cu30.5Y11)90Be10 and (Mg58.5Cu30.5Y11)90(Ti0.7Be0.3)10 alloys are 797.6, 952.6 and 1007.8 MPa, respectively, and the strengths are increased by about 17%, 40% and 48% compared with Mg58.5Cu30.5Y11 alloy. The strength reliability for the three alloys is much improved according to the strength distribution region of 10 samples of each alloy.展开更多
We review the latest aeromagnetic geological data of continental China. We discuss the latest achievements in geological mapping and the newly detected features based on aeromagnetic data. Using aeromagnetic data coll...We review the latest aeromagnetic geological data of continental China. We discuss the latest achievements in geological mapping and the newly detected features based on aeromagnetic data. Using aeromagnetic data collected for more than 50 years, a series of 1:5000000 and 1:1000000 aeromagnetic maps of continental China were compiled using state-of-the-art digital technology, and data processing and transformation. Guided by plate tectonics and continental dynamics, rock physical properties, and magnetic anomalies, we compiled maps of the depth of the magnetic basement of continental China and the major geotectonic units, and presented newly detected geological structures based on the aeromagnefic data.展开更多
Objective To observe the effects of y-aminobutyric acid (GABA) on the electric activities of pain-excited neurons (PEN) in nucleus accumbens (NAc) in central nervous system (CNS) of morphine-dependent rats. Me...Objective To observe the effects of y-aminobutyric acid (GABA) on the electric activities of pain-excited neurons (PEN) in nucleus accumbens (NAc) in central nervous system (CNS) of morphine-dependent rats. Methods After GABA or the GABAA-receptor antagonist, bicuculline (Bic), was injected into cerebral ventricles or NAc, right sciatic nerve was stimulated by electrical pulses, which was considered as traumatic pain stimulation. Extracellular recordings methods were used to record the electric activities of PEN in NAc. Results When GABA was injected into intracerebroventricle (ICV) as well as NAc, it could decrease the pain-evoked discharge frequency and prolong the latency of PEN. Bic could interdict the above effects of GABA on the electric activities of PEN. Conclusion Exogenous GABA might have an inhibitory effect on the central pain adjustment. Furthermore, GABA and GABAA receptor participate and mediate the traumatic information transmission process in CNS.展开更多
A hybrid technique is developed for the evaluation of two dimensional electromagnetic scattering from electrically large conducting bodies with cracks on their surfaces (TE case). The edge based finite element metho...A hybrid technique is developed for the evaluation of two dimensional electromagnetic scattering from electrically large conducting bodies with cracks on their surfaces (TE case). The edge based finite element method (FEM) is employed to compute the scattering from the cracks. Physical optics (PO) and physical theory of diffraction (PTD) are utilized to evaluate the scattering from the large bodies with the cracks filled with perfect conductors. These two methods are combined by an efficient coupling scheme. Some of numerical results are presented. It is shown that the hybrid technique has some advantages over other methods in regard to saving computer memory units and CPU time.展开更多
[Objective] Cloning of the AtrMYB transcription factor gene from Acer truncatum was conducted to further explore the red leaf development mechanism and breed cultivars of colored-leaf maple. [Method] The Acer truncat...[Objective] Cloning of the AtrMYB transcription factor gene from Acer truncatum was conducted to further explore the red leaf development mechanism and breed cultivars of colored-leaf maple. [Method] The Acer truncatum ‘Luhong No.1' cultivar was used as the material for cloning the MYB gene by mean of RTPCR and RACE-PCR. [Results] Sequence analysis showed that the fragment contained a full coding region of 831 bp encoding 276 amino acid residues with a molecular weight of 32.17 kD and a molecular formula C_(1430)H_(14052)N_(2247)O_(406)S_(14). The gene was named as AtrMYB with a Gen Bank accession number of 1825712. This coded protein had apI of 9.44. The results showed that the AtrMYB exhibited typical features of the R2R3-MYB domain. The AtrMYB was highly homologous with the MYB of other species at nucleotide and amino acid levels. The AtrMYB had no signal peptide, but a nuclear localization signal. The phylogenetic tree showed that the AtrMYB was at the same clade as the MYB from Citrus sinensis. [Conclusion] The AtrMYB was cloned from Acer truncatum ‘Luhong No.1' cultivar. These results have provided a foundation for further purification and identification of target protein and function study of the AtrMYB.展开更多
The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral co...The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed.展开更多
Based on the finite element (FE) program ANSYS, a three-dimensional model for the Runyang Suspension Bridge (RSB) is established. The structural natural frequency, vibration mode, stress and displacement response ...Based on the finite element (FE) program ANSYS, a three-dimensional model for the Runyang Suspension Bridge (RSB) is established. The structural natural frequency, vibration mode, stress and displacement response under various load cases are given. A new method of FE model updating is presented based on the physical meaning of sensitivity and the penalty function concept. In this method, the structural model is updated by modifying the parameters of design, and validated by structural natural vibration characteristics, stress response as well as displacement response. The design parameters used for updating are bounded according to measured static response and engineering judgment. The FE model of RSB is updated and validated by the measurements coming from the structural health monitoring system (SHMS), and the FE baseline model reflecting the current state of RSB is achieved. Both the dynamic and static results show that the method is effective in updating the FE model of long span suspension bridges. The results obtained provide an important research basis for damage alarming and health monitoring of the RSB.展开更多
The Co-Cr-W ternary system was critically assessed using the CALPHAD technique.The solution phases including the liquid,γ-Co,ε-Co and α-Cr were described by a substitutional solution model.The σ,μ and R phases we...The Co-Cr-W ternary system was critically assessed using the CALPHAD technique.The solution phases including the liquid,γ-Co,ε-Co and α-Cr were described by a substitutional solution model.The σ,μ and R phases were described by three-sublattice models of(Co,W)8(Cr,W)4(Co,Cr,W)18,(Co,Cr,W)7W2(Co,Cr,W)4 and(Co,W)27(Cr,W)14(Co,Cr,W)12,respectively,in order to reproduce their homogeneity ranges.A self-consistent set of thermodynamic parameters for each phase was derived.The calculated isothermal sections at 1 000,1 200 and 1 350 ℃ are in good agreement with the experimental data.A eutectoid reaction of R μ+γ-Co+σ in this ternary system was predicted to occur at 1 022 ℃.展开更多
AIM:To evaluate the association of human leukocyte antigen(HLA)-DQB1 alleles with hepatocellular carcinoma(HCC) through meta-analysis of published data.METHODS:Case-control studies on HLA-DQB1 allele association with ...AIM:To evaluate the association of human leukocyte antigen(HLA)-DQB1 alleles with hepatocellular carcinoma(HCC) through meta-analysis of published data.METHODS:Case-control studies on HLA-DQB1 allele association with HCC published up to January 2010 were included in the analyses.The odds ratios(ORs) of HLADQB1 allele distributions in HCC patients were analyzed and compared with healthy controls.The meta-analysis software REVMAN 5.0 was applied for investigating heterogeneity among individual studies and for summarizing all the studies.A meta-analysis was performed using fixed-effect or random-effect methods,depending on the absence or presence of significant heterogeneity.Seven case-control studies containing 398 cases and 594 controls were included in the final analysis.RESULTS:Among the five family alleles,two(DQB1*02 and DQB1*03) were found to be significantly associated with the risk of HCC.The combined OR for the association of DQB1*02 and DQB1*03 allele with the risk for HCC was 1.78(95% CI:1.05-3.03,P = 0.03) and 0.65(95% CI:0.48-0.89,P = 0.007),respectively.Among the 13 specific alleles,two(DQB1*0502 and DQB1*0602) were significantly associated with risk of HCC.The combined OR for the association of DQB1*0502 and DQB1*0602 allele with the risk for HCC was 1.82(95% CI:1.14-2.92,P = 0.01) and 0.58(95% CI:0.36-0.95,P = 0.03),respectively.No significant association was established for other HLA-DQB1 family alleles and specific alleles.CONCLUSION:Our results support the hypothesis that specific HLA-DQB1 allele families and alleles might influence the susceptibility or resistance to HCC,although it needs further investigations.展开更多
AIM: To investigate the effects of tachyplesin and n-sodium butyrate on proliferation and gene expression of human gastric adenocarcinoma cell line BGC-823. METHODS: Effects of tachyplesin and n-sodium butyrate on p...AIM: To investigate the effects of tachyplesin and n-sodium butyrate on proliferation and gene expression of human gastric adenocarcinoma cell line BGC-823. METHODS: Effects of tachyplesin and n-sodium butyrate on proliferation of BGC-823 cells were determined with trypan blue dye exclusion test and HE staining. Effects of tachyplesin and n-sodium butyrate on cell cycle were detected by flow cytometry. Protein levels of c-erbB-2, c-myc, p53 and p16 were examined by immunocytochemistry. RESULTS: The inhibiting effects were similar after 2.0 mg/L tachyplesin and 2.0 mmol/L n-sodium butyrate treatment, the inhibitory rate of cellular growth was 62.66% and 60.19% respectively, and the respective maximum mitotic index was decreased by 49.35% and 51.69% respectively. Tachyplesin and n-sodium buD/rate treatment could markedly increase the proportion of cells at G0/G1 phase and decrease the proportion at S phase. The expression levels of oncogene c-erbB-2, c-myc, and mtp53 proteins were down-regulated while the expression level of tumor suppressor gene p16 protein was up-regulated after the treatment with tachyplesin or n-sodium buD/rate. The effects of 1.0 mg/L tachyplesin in combination with 1.0 mmol/L n-sodium butyrate were obviously superior to their individual treatment in changing cell cycle distribution and expression of c-erbB-2, c-myc, mtp53 and p16 protein. The inhibitory rate of cellular growth of BGC-823 cells after combination treatment was 62.29% and the maximum mitotic index wasdecreased by 51.95%. CONCLUSION: Tachyplesin as a differentiation inducer of tumor cells has similar effects as n-sodium butyrate on proliferation of tumor cells, expression of correlative oncogene and tumor suppressor gene. It also has a synergistic effect on differentiation of tumor cells.展开更多
基金Supported by the Natural Foundation of Jiangsu Province(BK2004427)~~
文摘The calculation of earth pressure is a difficult problem in the pit foundation design. Aiming at the problem, the earth pressure calculation formulas considering the displacement are proposed. A method for determining the limit displacement is given and it is convenient for use. The result indicates that the earth pressure calculated by the formulas is between the earth pressure at rest and the Rankine earth pressure, the formulas can reflect the change rules of active and passive earth pressures along with the displacement. Moreover, the calculation result using the formulas is approximate to the monitoring result. It confirms the validity of the formula deduction and the rationality of the calculation results. As for the passive earth pressure, the calculation method is theoretically feasible.
基金Department of Science & Technology of GuangdongProvince (No.0509119).
文摘Aim To determine and analyze fatty acids, amino acids and trace elements of Hirudinaria manillensis. Methods Contents of fatty acids, amino acids and trace elements were determined by GC/MS, HPLC and ICP-AES. Results H. manillensis contained sixteen fatty acids, among which the percentage of unsaturated fatty acids is 34.05%. The eighteen amino acids were detected, which included eight essential amino acids in human body with a ratio of 33.53 %. There were eight trace elements (Ca, Cr, Cu, Fe, Mg, Mn, V and Zn) from H. manillensis, and the content of Ca, Zn and Fe were apparently higher than those of other elements. Conclusion These methods are simple and accurate. This study reports routine quantitative methods for the analysis of multiple components in H. manillensis by GC/MS, HPLC and ICP-AES.
基金funded by the foundation of HUST-WISCO Joint Laboratory
文摘A new Ni-based superalloy Ni48Cr28W5Co3Mn1Si1.6 was developed and the influence of a trace amount of rare earth (RE) metal addition on the oxidation resistance of this alloy was investigated. Isothermal oxidation behavior was investigated at 950?1150 °C in air, and then analyzed using scanning electronic microscopy and X-ray diffraction. The results showed that oxidation mass gain kinetics of the samples with and without RE elements follow the parabolic law. The effect of 0.20% RE on oxidation resistance is relatively small, and the oxidation rate constant of the alloy modified with 0.20% RE addition decreases by 5.9%?9.0%. Oxidation at 950?1150 °C for 100 h results in the formation of MnCr2O4, Cr2O3 and SiO2. A continuous and protective MnCr2O4 spinel layer forms as outer layer. The continuous middle oxide layer is confirmed to be Cr2O3, and the innermost layer consists of discontinuous SiO2.
文摘The absorbing process in isolating and coating process of α-olefin drag reducing polymer was studied by molecular dynamic simulation method, on basis of coating theory of α-olefin drag reducing polymer particles with polyurethane as coating material. The distributions of sodium laurate, sodium dodeeyl sulfate, and sodium dodeeyl benzene sulfonate on the surface of α-olefin drag reducing polymer particles were almost the same, but the bending degrees of them were obviously different. The bending degree of SLA molecules was greater than those of the other two surfactant molecules. Simulation results of absorbing and accumulating structure showed that, though hydrophobie properties of surfactant molecules were almost the same, water density around long chain sulfonate sodium was bigger than that around alkyl sulfate sodium. This property goes against useful absorbing and accumulating on the surface of α-olefin drag reducing polymer particles; simulation results of interactions of different surfactant and multiple hydroxyl compounds on surface of particles showed that, interactions of different surfaetant and one kind of multiple hydroxyl compound were similar to those of one kind of surfaetant and different multiple hydroxyl compounds. These two contrast types of interactions also exhibited the differences of absorbing distribution and closing degrees to surface of particles. The sequence of closing degrees was derived from simulation; control step of addition polymerization interaction in coating process was absorbing mass transfer process, so the more closed to surface of particle the multiple hydroxyl compounds were, the easier interactions With isoeyanate were. Simulation results represented the compatibility relationship between surfactant and multiple hydroxyl compounds. The isolating and coating processes of α-olefin drag reducing polymer were further understood on molecule and atom level through above simulation research, and based on the simulation, a referenced theoretical basis was provided for practical optimal selection and experimental preparation of α-olefin drag reducing polymer particles suspension isolation agent.
文摘Neural stem cell is presently the research hotspot in neuroscience. Recent progress indicates that epigenetic modulation is closely related to the self-renewal and differentiation of neural stem cell. Epigenetics refer to the study of mitotical/meiotical heritage changes in gene function that cannot be explained by changes in the DNA sequence. Major epigenetic mechanisms include DNA methylation, histone modification, chromatin remodeling, genomic imprinting, and non-coding RNA. In this review, we focus on the new insights into the epigenetic mechanism for neural stem cells fate.
文摘The rollup and the drilldown are quite frequent based on dimension hierarchies in on-line analytical processing (OLAP), but prefixCube does not directly support dimension hierarchies. The PrefixCube is extended for incorporating hierarchical data cubes, i.e. cubes with hierarchical dimensions ,thus obtaining HierPrefixCube. HierPrefixCube retains advantages on computation and organization of PrefixCube, and it can directly support aggregate queries on levels of the dimension hierarchy.
基金Project (2011CB605505) supported by the National Basic Research Program of ChinaProject (2011JQ002) supported by the Fundamental Research Funds for the Central Universities, China
文摘Based on the analyses of the microstructures and phase diagrams of the TiAl-based alloy, the relationship among the composition, structure and mechanical properties of the B2-containing y-TiAI alloys was reviewed. The refinement of microstructures and improvement of mechanical properties of TiA1 alloy through stabilization of the β/B2 phase were reviewed. The mechanism of the superplastic behavior of the B2-containing y-TiAI alloys was discussed. With a reasonable addition of β-stabilizer, metastable B2 phase can be maintained, which is favorable for fine-grained structure and better high-temperature deformation behaviors. The mechanical properties of the B2-containing TiAI alloy, including the deformability and elevated temperature properties, can also be improved with doping elements and subsequent hot-working processes. The above mentioned researches discuss a new way for developing TiAI alloys with comprehensive properties, including good deformability and creep resistance.
基金Project(2011CB606301)supported by the National Basic Research Program of China
文摘Based on the Mg58.5Cu30.5Y11 alloy, 10% Ti, 10% Be and 10% Ti70Be30 (mole fraction) were respectively added to the alloy and samples with a diameter of 3 mm were fabricated by conventional Cu-mold casting method. The phase constituent, thermal stability and microstructure of the alloys were investigated by using X-ray diffraction, differential scanning calorimetry and scanning electron microscopy, respectively. The effects of alloying elements Ti and Be on the microstructure and mechanical properties of Mg58.sCu3o.sYll alloy were discussed. The results show that CuTi phase is distributed in (Mg0.585Cu0.305Y0.11)90Ti10 and (Mg58.5Cu30.5Y11)90(Ti0.7Be0.3)10 alloys, while CuYBe glassy phase containing CuY crystals is embedded in the matrix of (Mg58.5Cu30.5Y11)90Be10 alloy. Under uniaxial compressive loading, the largest compressive fracture strengths for (Mg58.5Cu30.5Y11)90Ti10, (Mg58.5Cu30.5Y11)90Be10 and (Mg58.5Cu30.5Y11)90(Ti0.7Be0.3)10 alloys are 797.6, 952.6 and 1007.8 MPa, respectively, and the strengths are increased by about 17%, 40% and 48% compared with Mg58.5Cu30.5Y11 alloy. The strength reliability for the three alloys is much improved according to the strength distribution region of 10 samples of each alloy.
基金supported by the China Land Aeromagnetic Characteristics and Tectonic Structures Research(No.1212011087009)part of the national geological and mineral resources investigation projects,and the Comprehensive Exploration of Aero Geophysical&Remote Sensing Survey and Interpretation System Research(No.2013AA063905)part of the planning for national high technology research and development
文摘We review the latest aeromagnetic geological data of continental China. We discuss the latest achievements in geological mapping and the newly detected features based on aeromagnetic data. Using aeromagnetic data collected for more than 50 years, a series of 1:5000000 and 1:1000000 aeromagnetic maps of continental China were compiled using state-of-the-art digital technology, and data processing and transformation. Guided by plate tectonics and continental dynamics, rock physical properties, and magnetic anomalies, we compiled maps of the depth of the magnetic basement of continental China and the major geotectonic units, and presented newly detected geological structures based on the aeromagnefic data.
基金the National Natural Science Foundation of China (No. 60601010)the Natural Science Foundation of Heilongjiang Province, China (No. D200606)+1 种基金the Postdoctoral Fund of Heilongjiang province, China (No. LBH-Z06110)the Scientific Re- search Fund of Educational Department of Heilongjiang Province, China (No. 11531112).
文摘Objective To observe the effects of y-aminobutyric acid (GABA) on the electric activities of pain-excited neurons (PEN) in nucleus accumbens (NAc) in central nervous system (CNS) of morphine-dependent rats. Methods After GABA or the GABAA-receptor antagonist, bicuculline (Bic), was injected into cerebral ventricles or NAc, right sciatic nerve was stimulated by electrical pulses, which was considered as traumatic pain stimulation. Extracellular recordings methods were used to record the electric activities of PEN in NAc. Results When GABA was injected into intracerebroventricle (ICV) as well as NAc, it could decrease the pain-evoked discharge frequency and prolong the latency of PEN. Bic could interdict the above effects of GABA on the electric activities of PEN. Conclusion Exogenous GABA might have an inhibitory effect on the central pain adjustment. Furthermore, GABA and GABAA receptor participate and mediate the traumatic information transmission process in CNS.
文摘A hybrid technique is developed for the evaluation of two dimensional electromagnetic scattering from electrically large conducting bodies with cracks on their surfaces (TE case). The edge based finite element method (FEM) is employed to compute the scattering from the cracks. Physical optics (PO) and physical theory of diffraction (PTD) are utilized to evaluate the scattering from the large bodies with the cracks filled with perfect conductors. These two methods are combined by an efficient coupling scheme. Some of numerical results are presented. It is shown that the hybrid technique has some advantages over other methods in regard to saving computer memory units and CPU time.
基金Supported by Agricultural Elite Cultivar Project of Shandong Province(lkz2014[96])~~
文摘[Objective] Cloning of the AtrMYB transcription factor gene from Acer truncatum was conducted to further explore the red leaf development mechanism and breed cultivars of colored-leaf maple. [Method] The Acer truncatum ‘Luhong No.1' cultivar was used as the material for cloning the MYB gene by mean of RTPCR and RACE-PCR. [Results] Sequence analysis showed that the fragment contained a full coding region of 831 bp encoding 276 amino acid residues with a molecular weight of 32.17 kD and a molecular formula C_(1430)H_(14052)N_(2247)O_(406)S_(14). The gene was named as AtrMYB with a Gen Bank accession number of 1825712. This coded protein had apI of 9.44. The results showed that the AtrMYB exhibited typical features of the R2R3-MYB domain. The AtrMYB was highly homologous with the MYB of other species at nucleotide and amino acid levels. The AtrMYB had no signal peptide, but a nuclear localization signal. The phylogenetic tree showed that the AtrMYB was at the same clade as the MYB from Citrus sinensis. [Conclusion] The AtrMYB was cloned from Acer truncatum ‘Luhong No.1' cultivar. These results have provided a foundation for further purification and identification of target protein and function study of the AtrMYB.
文摘The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed.
文摘Based on the finite element (FE) program ANSYS, a three-dimensional model for the Runyang Suspension Bridge (RSB) is established. The structural natural frequency, vibration mode, stress and displacement response under various load cases are given. A new method of FE model updating is presented based on the physical meaning of sensitivity and the penalty function concept. In this method, the structural model is updated by modifying the parameters of design, and validated by structural natural vibration characteristics, stress response as well as displacement response. The design parameters used for updating are bounded according to measured static response and engineering judgment. The FE model of RSB is updated and validated by the measurements coming from the structural health monitoring system (SHMS), and the FE baseline model reflecting the current state of RSB is achieved. Both the dynamic and static results show that the method is effective in updating the FE model of long span suspension bridges. The results obtained provide an important research basis for damage alarming and health monitoring of the RSB.
基金Project(50771027)supported by the National Basic Research Program of ChinaProject(50771027)supported by the National Natural Science Foundation of China
文摘The Co-Cr-W ternary system was critically assessed using the CALPHAD technique.The solution phases including the liquid,γ-Co,ε-Co and α-Cr were described by a substitutional solution model.The σ,μ and R phases were described by three-sublattice models of(Co,W)8(Cr,W)4(Co,Cr,W)18,(Co,Cr,W)7W2(Co,Cr,W)4 and(Co,W)27(Cr,W)14(Co,Cr,W)12,respectively,in order to reproduce their homogeneity ranges.A self-consistent set of thermodynamic parameters for each phase was derived.The calculated isothermal sections at 1 000,1 200 and 1 350 ℃ are in good agreement with the experimental data.A eutectoid reaction of R μ+γ-Co+σ in this ternary system was predicted to occur at 1 022 ℃.
基金Supported by Shandong Provincial Natural Science Foundation,China,No. ZR2009CQ031
文摘AIM:To evaluate the association of human leukocyte antigen(HLA)-DQB1 alleles with hepatocellular carcinoma(HCC) through meta-analysis of published data.METHODS:Case-control studies on HLA-DQB1 allele association with HCC published up to January 2010 were included in the analyses.The odds ratios(ORs) of HLADQB1 allele distributions in HCC patients were analyzed and compared with healthy controls.The meta-analysis software REVMAN 5.0 was applied for investigating heterogeneity among individual studies and for summarizing all the studies.A meta-analysis was performed using fixed-effect or random-effect methods,depending on the absence or presence of significant heterogeneity.Seven case-control studies containing 398 cases and 594 controls were included in the final analysis.RESULTS:Among the five family alleles,two(DQB1*02 and DQB1*03) were found to be significantly associated with the risk of HCC.The combined OR for the association of DQB1*02 and DQB1*03 allele with the risk for HCC was 1.78(95% CI:1.05-3.03,P = 0.03) and 0.65(95% CI:0.48-0.89,P = 0.007),respectively.Among the 13 specific alleles,two(DQB1*0502 and DQB1*0602) were significantly associated with risk of HCC.The combined OR for the association of DQB1*0502 and DQB1*0602 allele with the risk for HCC was 1.82(95% CI:1.14-2.92,P = 0.01) and 0.58(95% CI:0.36-0.95,P = 0.03),respectively.No significant association was established for other HLA-DQB1 family alleles and specific alleles.CONCLUSION:Our results support the hypothesis that specific HLA-DQB1 allele families and alleles might influence the susceptibility or resistance to HCC,although it needs further investigations.
基金Supported by the National Natural Science Foundation of China, No.30170724
文摘AIM: To investigate the effects of tachyplesin and n-sodium butyrate on proliferation and gene expression of human gastric adenocarcinoma cell line BGC-823. METHODS: Effects of tachyplesin and n-sodium butyrate on proliferation of BGC-823 cells were determined with trypan blue dye exclusion test and HE staining. Effects of tachyplesin and n-sodium butyrate on cell cycle were detected by flow cytometry. Protein levels of c-erbB-2, c-myc, p53 and p16 were examined by immunocytochemistry. RESULTS: The inhibiting effects were similar after 2.0 mg/L tachyplesin and 2.0 mmol/L n-sodium butyrate treatment, the inhibitory rate of cellular growth was 62.66% and 60.19% respectively, and the respective maximum mitotic index was decreased by 49.35% and 51.69% respectively. Tachyplesin and n-sodium buD/rate treatment could markedly increase the proportion of cells at G0/G1 phase and decrease the proportion at S phase. The expression levels of oncogene c-erbB-2, c-myc, and mtp53 proteins were down-regulated while the expression level of tumor suppressor gene p16 protein was up-regulated after the treatment with tachyplesin or n-sodium buD/rate. The effects of 1.0 mg/L tachyplesin in combination with 1.0 mmol/L n-sodium butyrate were obviously superior to their individual treatment in changing cell cycle distribution and expression of c-erbB-2, c-myc, mtp53 and p16 protein. The inhibitory rate of cellular growth of BGC-823 cells after combination treatment was 62.29% and the maximum mitotic index wasdecreased by 51.95%. CONCLUSION: Tachyplesin as a differentiation inducer of tumor cells has similar effects as n-sodium butyrate on proliferation of tumor cells, expression of correlative oncogene and tumor suppressor gene. It also has a synergistic effect on differentiation of tumor cells.