The high-efficiency Shock Vectoring Control Serpentine Nozzle(SVCSN)takes into account both thrust vectoring and infrared stealth,and significantly improves the comprehensive performance of the aero-engines through an...The high-efficiency Shock Vectoring Control Serpentine Nozzle(SVCSN)takes into account both thrust vectoring and infrared stealth,and significantly improves the comprehensive performance of the aero-engines through an additional auxiliary duct.In this paper,the schlieren photographs at the exit of the high-efficiency SVCSN and the wall static pressure distributions were obtained by experiments,and the numerical results were used to enrich the thrust vectoring characteristics.The effects of the auxiliary injection were analyzed first to reveal the advantages of the high-efficiency SVCSN compared to the conventional SVCSN.Then,the aerodynamic parameters and the structural parameters of the high-efficiency SVCSN were investigated,including the Nozzle Pressure Ratio(NPR),the Secondary flow Pressure Ratio(SPR),the secondary flow relative area and the secondary flow injection angle.Finally,the coupling performance of the high-efficiency SVCSN is studied by using the approximate modeling technology.Results show that the auxiliary injection increases the range between the two shock legs of the “k”shock wave induced by the secondary flow,then causes the separation zone and high-pressure boss of the down wall to expand upstream,and finally results in a prominent increase in the thrust vectoring performance.The thrust vectoring angle and Vectoring Efficiency(VE)of the high-efficiency SVCSN are about 61.6%and 75.7%,respectively,higher than those of the conventional SVCSN at NPR=6.The effects of the NPR and the SPR on the thrust vectoring performance of the high-efficiency SVCSN are coupled with each other.A larger NPR matched with a smaller SPR shows better thrust vectoring performance.The maximum fluctuations in thrust vectoring angle and VE caused by the NPR and SPR are about 22%and 64%.The VE decreases monotonously with the increase of the secondary flow relative area.Smaller secondary flow injection angle shows better thrust vector performance,and the thrust vectoring angle and VE of the secondary flow injection angle of 90are about 20%higher than those of the secondary flow injection angle of 110at NPR=6.Therefore,the secondary flow relative area of 0.06 and the secondary flow injection angle of 90are recommended.展开更多
[ Objective ] Heat shock factors (HSFs) are the major transcription factors of eukaryotic heat shock responses. This study aims to investigate the adversity stress tolerance functions of Arabidopsis heat shock facto...[ Objective ] Heat shock factors (HSFs) are the major transcription factors of eukaryotic heat shock responses. This study aims to investigate the adversity stress tolerance functions of Arabidopsis heat shock factor AtHsfAla, which has important significance for in-depth understanding of adversity stress tolerance mechanisms of plants and further utilization of heat shock factor genes. [Method] Genomic DNA of Arabidopsis was extracted with CTAB method and purified to obtain Arabidopsis DNA samples for in vitro site-specific recombination cloning ( Gateway cloning) to construct plant expression vector of heat shock factor AtHs- fAla. Firstly, donor vector pDONR 201/AtHsfAla was constructed based on attB and attP site-specific recombination method (BP reaction), to identify E. coli transformants harboring correct sequence of AtHsfAla by sequencing; secondly, plant expression vector pBTWG2/AttlsfAla overexpressing Arabidopsis heat shock factor AtHsfAla was constructed based on attL and attR site-specific recombination method (LR reaction), to screen E. coli transformants harboring target plasmid. [ Result] Plant expression vector of Arabidopsis heat shock factor gene AtHsfAla was constructed successfully. [ Conclusion] This study not only provided experimental materials for acquiring transgenic plants overexpressing heat shock transcription factor AtHsfAla, but also laid the foundation for further investigation of the diversity of adversity stress tolerance functions reanlated by HSFs.展开更多
Heat shock protein 65 (HSP65) is one of the most important protective immunogens against the tuberculosis infection. The signal sequence of antigen 85B and the whole HSP65 DNA sequence of human Mycobacterium tuberculo...Heat shock protein 65 (HSP65) is one of the most important protective immunogens against the tuberculosis infection. The signal sequence of antigen 85B and the whole HSP65 DNA sequence of human Mycobacterium tuberculosis (M. tuberculosis) were amplified from BCG genome and plasmid pCMV-MTHSP65 respectively by polymerase chain reactions (PCR). These two sequences were cloned into the plasmid pBCG-2100 under the control of the promoter of heat shock protein 70 (HSP70) from human M. tuberculosis, yielding the prokaryotic shuttle expression plasmid pBCG-SP-HSP65. Results of restriction endonuclease analysis, PCR detection and DNA sequencing analysis showed that the two cloned DNA sequences were consistent with those previously reported, and the direction of their inserting into the recombinant was correct and the reading frame had been maintained. The recombinants were electroporated into BCG to construct the recombinant BCG vaccine and induced by heating. The induced expression detected by SDS-PAGE showed that the content of 65 kD protein expressed in recombinant BCG was 35.69 % in total bacterial protein and 74.09 % in the cell lysate supernatants, suggesting that the recombinant HSP65 gene could express in BCG with high efficiency and the expressed proteins were mainly soluble. Western-blot showed that the secretive recombinant proteins could specifically combine with antibody against M. tuberculosis HSP65, indicating that the recombinant proteins possess the biological activity of HSP65.展开更多
基金supported by the Science Center for Gas Turbine Project,China(Nos.P2022-B-Ⅱ-010-001 and P2022-B-I-002-001)the National Natural Science Foundation of China(Nos.52376032 and 52076180)+2 种基金the Funds for Distinguished Young Scholars of Shaanxi Province,China(No.2021JC-10)the National Science and Technology Major Project,China(No.J2019-Ⅱ-0015-0036)the Fundamental Research Funds for the Central Universities,China(No.501XTCX2023146001).
文摘The high-efficiency Shock Vectoring Control Serpentine Nozzle(SVCSN)takes into account both thrust vectoring and infrared stealth,and significantly improves the comprehensive performance of the aero-engines through an additional auxiliary duct.In this paper,the schlieren photographs at the exit of the high-efficiency SVCSN and the wall static pressure distributions were obtained by experiments,and the numerical results were used to enrich the thrust vectoring characteristics.The effects of the auxiliary injection were analyzed first to reveal the advantages of the high-efficiency SVCSN compared to the conventional SVCSN.Then,the aerodynamic parameters and the structural parameters of the high-efficiency SVCSN were investigated,including the Nozzle Pressure Ratio(NPR),the Secondary flow Pressure Ratio(SPR),the secondary flow relative area and the secondary flow injection angle.Finally,the coupling performance of the high-efficiency SVCSN is studied by using the approximate modeling technology.Results show that the auxiliary injection increases the range between the two shock legs of the “k”shock wave induced by the secondary flow,then causes the separation zone and high-pressure boss of the down wall to expand upstream,and finally results in a prominent increase in the thrust vectoring performance.The thrust vectoring angle and Vectoring Efficiency(VE)of the high-efficiency SVCSN are about 61.6%and 75.7%,respectively,higher than those of the conventional SVCSN at NPR=6.The effects of the NPR and the SPR on the thrust vectoring performance of the high-efficiency SVCSN are coupled with each other.A larger NPR matched with a smaller SPR shows better thrust vectoring performance.The maximum fluctuations in thrust vectoring angle and VE caused by the NPR and SPR are about 22%and 64%.The VE decreases monotonously with the increase of the secondary flow relative area.Smaller secondary flow injection angle shows better thrust vector performance,and the thrust vectoring angle and VE of the secondary flow injection angle of 90are about 20%higher than those of the secondary flow injection angle of 110at NPR=6.Therefore,the secondary flow relative area of 0.06 and the secondary flow injection angle of 90are recommended.
基金Supported by National Natural Science Foundation of China(31060039,31260061)Natural Science Foundation of Yunnan Province(2010ZC163)+1 种基金Project of Kunming University(YJL11025)Fund for Key Discipline Construction of Kunming University
文摘[ Objective ] Heat shock factors (HSFs) are the major transcription factors of eukaryotic heat shock responses. This study aims to investigate the adversity stress tolerance functions of Arabidopsis heat shock factor AtHsfAla, which has important significance for in-depth understanding of adversity stress tolerance mechanisms of plants and further utilization of heat shock factor genes. [Method] Genomic DNA of Arabidopsis was extracted with CTAB method and purified to obtain Arabidopsis DNA samples for in vitro site-specific recombination cloning ( Gateway cloning) to construct plant expression vector of heat shock factor AtHs- fAla. Firstly, donor vector pDONR 201/AtHsfAla was constructed based on attB and attP site-specific recombination method (BP reaction), to identify E. coli transformants harboring correct sequence of AtHsfAla by sequencing; secondly, plant expression vector pBTWG2/AttlsfAla overexpressing Arabidopsis heat shock factor AtHsfAla was constructed based on attL and attR site-specific recombination method (LR reaction), to screen E. coli transformants harboring target plasmid. [ Result] Plant expression vector of Arabidopsis heat shock factor gene AtHsfAla was constructed successfully. [ Conclusion] This study not only provided experimental materials for acquiring transgenic plants overexpressing heat shock transcription factor AtHsfAla, but also laid the foundation for further investigation of the diversity of adversity stress tolerance functions reanlated by HSFs.
文摘Heat shock protein 65 (HSP65) is one of the most important protective immunogens against the tuberculosis infection. The signal sequence of antigen 85B and the whole HSP65 DNA sequence of human Mycobacterium tuberculosis (M. tuberculosis) were amplified from BCG genome and plasmid pCMV-MTHSP65 respectively by polymerase chain reactions (PCR). These two sequences were cloned into the plasmid pBCG-2100 under the control of the promoter of heat shock protein 70 (HSP70) from human M. tuberculosis, yielding the prokaryotic shuttle expression plasmid pBCG-SP-HSP65. Results of restriction endonuclease analysis, PCR detection and DNA sequencing analysis showed that the two cloned DNA sequences were consistent with those previously reported, and the direction of their inserting into the recombinant was correct and the reading frame had been maintained. The recombinants were electroporated into BCG to construct the recombinant BCG vaccine and induced by heating. The induced expression detected by SDS-PAGE showed that the content of 65 kD protein expressed in recombinant BCG was 35.69 % in total bacterial protein and 74.09 % in the cell lysate supernatants, suggesting that the recombinant HSP65 gene could express in BCG with high efficiency and the expressed proteins were mainly soluble. Western-blot showed that the secretive recombinant proteins could specifically combine with antibody against M. tuberculosis HSP65, indicating that the recombinant proteins possess the biological activity of HSP65.