Experimental and theoretical studies of drag embedment plate anchors recently carried out in Tianjin University are summarized in this research paper, which involve a series of important topics relevant to the study o...Experimental and theoretical studies of drag embedment plate anchors recently carried out in Tianjin University are summarized in this research paper, which involve a series of important topics relevant to the study of drag anchors. The techniques for measuring the trajectory and movement direction of drag anchors in soils, the techniques for measuring the moving embedment point and reverse eatenary shape of the embedded drag line, the penetration mechanism and kinematic behavior of drag anchors, the ultimate embedment depth of drag anchors, the movement direction of the anchor with an arbitrary fluke section, the reverse catenary properties of the embedded drag line, the interaetional properties between drag anchor and installation line, the kinematic model of drag anchors in seabed soils, and the analytical method for predicting the anchor trajectory in soils will all be examined. The present work remarkably reduces the uncertainties in design and analysis of drag embedment plate anchors, and is beneficial to improving the application of this new type of drag anchor in offshore engineering.展开更多
In this study,a process for establishing design requirements and selecting alternative configurations for the conceptual phase of aircraft design has been proposed.The proposed process uses system-engineering-based re...In this study,a process for establishing design requirements and selecting alternative configurations for the conceptual phase of aircraft design has been proposed.The proposed process uses system-engineering-based requirement-analysis techniques such as objective tree,analytic hierarchy process,and quality function deployment to establish logical and quantitative standards.Moreover,in order to perform a logical selection of alternative aircraft configurations,it uses advanced decision-making methods such as morphological matrix and technique for order preference by similarity to the ideal solution.In addition,a preliminary sizing tool has been developed to check the feasibility of the established performance requirements and to evaluate the flight performance of the selected configurations.The present process has been applied for a two-seater very light aircraft（VLA）,resulting in a set of tentative design requirements and two families of VLA configurations：a high-wing configuration and a low-wing configuration.The resulting set of design requirements consists of three categories：customer requirements,certification requirements,and performance requirements.The performance requirements include two mission requirements for the flight range and the endurance by reflecting the customer requirements.The flight performances of the two configuration families were evaluated using the sizing tool developed and the low-wing configuration with conventional tails was selected as the best baseline configuration for the VLA.展开更多
This work was supported by grants from the National Natural Science Foundation of China.No. (39730420). ** To whom requests for reprints should be addressed.This is one of papers of the special issue on gene...This work was supported by grants from the National Natural Science Foundation of China.No. (39730420). ** To whom requests for reprints should be addressed.This is one of papers of the special issue on gene therapy research (Chin J Cancer Res Vol. 9 No. 4 December, 1997). Vascular cell adhesion molecule 1 (VCAM 1) is a member of immunoglobulin superfamily. The principal ligand for VCAM 1 is integrin α4β1/VLA 4 (very late antigen 4). It was reported that VCAM 1 was expressed on macrophages and dendritic cells, but little is known about its function on these professional antigen pre senting cells (APC). The present study was performed to investigate the expression of VCAM 1 on macrophages and the role of VCAM 1/VLA 4 in the activation of allogenic T cells by murine macrophages. We analyzed VCAM 1 expression on peritoneal macrophages and macrophage cell line J774A.1 by fluorescence activated cell sorting (FACS). Using neutralizing antibodies, we further analyzed the role of VCAM 1/VLA 4 interaction in macrophage and allogenic T cell mixed lymphocyte reaction (MLR). We found that VCAM 1 was consti tutively expressed on macrophages and its expression level was upregulated by soluble tumor associated antigen (freeze thaw lysates of FBL 3 leukemia cells) and TNF α. In MLR assays, we observed that blocking VCAM 1/VLA 4 interaction with anti VCAM 1 or anti VLA 4 mAbs caused significant inhibition of the proliferative response and IL 2 production. These results suggest that VCAM 1on macrophages not only facilitates the cell to cell contact through adhesive interaction but also plays a role in the costimulation of T cells via its interaction with VLA 4 on the T cells.展开更多
Using the BNL Accelerator Test Facility we have shown that a tightly focused laser on a vacuum can accelerate an electron beam in free space. The electron beam had energy of 20 MeV and the CO2 laser had energy of abou...Using the BNL Accelerator Test Facility we have shown that a tightly focused laser on a vacuum can accelerate an electron beam in free space. The electron beam had energy of 20 MeV and the CO2 laser had energy of about 3 Joule. In the readout of the experiment we detect a clear effect for the laser beam off and on. The size of the effect is about 20% and is reproducible over many laser and beam shots. This is a proof of principle and the data are fully consistent with the CAS theory. The results of this experiment may have an impact on the LASER fusion method.展开更多
We present radio images of the compact steep spectrum (CSS) quasar 3C 286 acquired with the Very Large Array (VLA) at 8.4 and 22.5 GHz. The source exhibits a two-sided core-jet structure with a bright central componen...We present radio images of the compact steep spectrum (CSS) quasar 3C 286 acquired with the Very Large Array (VLA) at 8.4 and 22.5 GHz. The source exhibits a two-sided core-jet structure with a bright central component and two extended components one to the east (P.A. 100°) and another to the southwest (P.A. - 116°). From the compact core, an extension runs towards the southwest component up to - 0.7 arcsecond. The emission between the primary central component and the southwest component exhibits a knotty structure. A gradual change of the jet position angles from -135° to -120° in the inner southwest jet suggests a local bend. The position angle changes of the major eastern components E2 and El suggest that the eastern jet likely follows a curved trace. The bends in the jet trace may be associated with a relativistic precession or some interaction between the jet and the ambient matter. A mean spectral index of a22.58.4- 0.76 (Xv Va) is estimated for the core component. Steep spectra are also obtained for the extended southwest component (2.6', P.A. -116°) and eastern component (0.8', P.A. 100°), with a22.58.4-0.88 and a22.58.4-1.79, respectively. The radio morphologies and spectral index distributions suggest that the core seen in our images is likely to be the beamed inner jet while the real nucleus is dimmed by it beaming away from us.展开更多
We observed 1938-155, a broad line radio galaxy (BLRG), with the Very Large Array (VLA) at 90cm with an angular resolution of 6.8' × 4.0'. The source consists of two components separated by 4 arcsec (- 20...We observed 1938-155, a broad line radio galaxy (BLRG), with the Very Large Array (VLA) at 90cm with an angular resolution of 6.8' × 4.0'. The source consists of two components separated by 4 arcsec (- 20kpc, for H0 = 65km s-1 Mpc-1, q0 = 0.5) along the SE-NW direction. Both components show steep-spectra with a similar spectral index α - 0.83 ± 0.07 (Sv ∝ v-α). The bright double components are surrounded by a low-brightness cocoon. The radio properties of the two bright components are consistent with the hot spots produced by twin jets. An upper limit of - 0.0008 for the core dominance parameter (R) is inferred, suggesting there is no prominent radio core in the source. Assuming a modest viewing angle 30f77, a jet velocity is estimated - 0.07 c, based on the jet to counter-jet brightness ratio (J). The lower limit in jet speed inferred is consistent with no Doppler beaming effect on the jet. The radio galaxy 1938-155 could be an exceptional BLRG with no prominent radio core or jet.展开更多
The sanitary and environmental challenges posed by an ever growing economically and geographically diverse human population include the need for sustainable, inexpensive, scalable, and decentralized water treatment te...The sanitary and environmental challenges posed by an ever growing economically and geographically diverse human population include the need for sustainable, inexpensive, scalable, and decentralized water treatment technologies that can supplement or replace conventional treatment methods. These challenges can be met by semiconductor photocatalysis, especially if the process is driven by visible light energy. Visible-light active (VLA) photocatalysis, as opposed to traditional energy-intensive and chemically driven disinfection methods such as ozonation, UV irradiation and chlorination, has the potential for achieving high disinfection efficiency with low energy consumption and no harmful by-products. This technology generates in-situ reactive oxygen species (ROS) such as H2O2, and?, without the need for chemicals addition. In turn, ROS are capable of penetrating cell walls and membranes of microorganisms, effectively inactivating them. Although multiple types of VLA photocatalysts have been used experimentally for disinfection of water, noble-metal-based photocatalysts have gained the most interest due to their surface plasma resonance (SPR) effect, which acts synergistically to increase the disinfection potential of the photocatalytic process. This paper is a review of the different types of noble-metal-based VLA photocatalysts used for water disinfection in different experimental settings, their synthesis procedures and disinfection mechanisms. It also discusses innovative approaches to overcome a major hurdle in photocatalysis, that is, the rapid recombination of the electron and hole pair, by including specific dopants into the structure of the photocatalyst.展开更多
基金Foundation item： Supported by the National Natural Science Foundation of China （Grant nos. 50639030 and 50979070） and the 863 Program of China （Grant no. 2006AA09Z348）.
文摘Experimental and theoretical studies of drag embedment plate anchors recently carried out in Tianjin University are summarized in this research paper, which involve a series of important topics relevant to the study of drag anchors. The techniques for measuring the trajectory and movement direction of drag anchors in soils, the techniques for measuring the moving embedment point and reverse eatenary shape of the embedded drag line, the penetration mechanism and kinematic behavior of drag anchors, the ultimate embedment depth of drag anchors, the movement direction of the anchor with an arbitrary fluke section, the reverse catenary properties of the embedded drag line, the interaetional properties between drag anchor and installation line, the kinematic model of drag anchors in seabed soils, and the analytical method for predicting the anchor trajectory in soils will all be examined. The present work remarkably reduces the uncertainties in design and analysis of drag embedment plate anchors, and is beneficial to improving the application of this new type of drag anchor in offshore engineering.
基金the support provided for this research by a grant(No.1615001723) from the Light Aircraft Development Program funded by the Ministry of Land,Infrastructure and Transport of the Korean governmentthe National Research Foundation of Korea(No.NRF-2014R1A2A2A01003833) funded by the Korean government(MSIP)
文摘In this study,a process for establishing design requirements and selecting alternative configurations for the conceptual phase of aircraft design has been proposed.The proposed process uses system-engineering-based requirement-analysis techniques such as objective tree,analytic hierarchy process,and quality function deployment to establish logical and quantitative standards.Moreover,in order to perform a logical selection of alternative aircraft configurations,it uses advanced decision-making methods such as morphological matrix and technique for order preference by similarity to the ideal solution.In addition,a preliminary sizing tool has been developed to check the feasibility of the established performance requirements and to evaluate the flight performance of the selected configurations.The present process has been applied for a two-seater very light aircraft（VLA）,resulting in a set of tentative design requirements and two families of VLA configurations：a high-wing configuration and a low-wing configuration.The resulting set of design requirements consists of three categories：customer requirements,certification requirements,and performance requirements.The performance requirements include two mission requirements for the flight range and the endurance by reflecting the customer requirements.The flight performances of the two configuration families were evaluated using the sizing tool developed and the low-wing configuration with conventional tails was selected as the best baseline configuration for the VLA.
文摘This work was supported by grants from the National Natural Science Foundation of China.No. (39730420). ** To whom requests for reprints should be addressed.This is one of papers of the special issue on gene therapy research (Chin J Cancer Res Vol. 9 No. 4 December, 1997). Vascular cell adhesion molecule 1 (VCAM 1) is a member of immunoglobulin superfamily. The principal ligand for VCAM 1 is integrin α4β1/VLA 4 (very late antigen 4). It was reported that VCAM 1 was expressed on macrophages and dendritic cells, but little is known about its function on these professional antigen pre senting cells (APC). The present study was performed to investigate the expression of VCAM 1 on macrophages and the role of VCAM 1/VLA 4 in the activation of allogenic T cells by murine macrophages. We analyzed VCAM 1 expression on peritoneal macrophages and macrophage cell line J774A.1 by fluorescence activated cell sorting (FACS). Using neutralizing antibodies, we further analyzed the role of VCAM 1/VLA 4 interaction in macrophage and allogenic T cell mixed lymphocyte reaction (MLR). We found that VCAM 1 was consti tutively expressed on macrophages and its expression level was upregulated by soluble tumor associated antigen (freeze thaw lysates of FBL 3 leukemia cells) and TNF α. In MLR assays, we observed that blocking VCAM 1/VLA 4 interaction with anti VCAM 1 or anti VLA 4 mAbs caused significant inhibition of the proliferative response and IL 2 production. These results suggest that VCAM 1on macrophages not only facilitates the cell to cell contact through adhesive interaction but also plays a role in the costimulation of T cells via its interaction with VLA 4 on the T cells.
文摘Using the BNL Accelerator Test Facility we have shown that a tightly focused laser on a vacuum can accelerate an electron beam in free space. The electron beam had energy of 20 MeV and the CO2 laser had energy of about 3 Joule. In the readout of the experiment we detect a clear effect for the laser beam off and on. The size of the effect is about 20% and is reproducible over many laser and beam shots. This is a proof of principle and the data are fully consistent with the CAS theory. The results of this experiment may have an impact on the LASER fusion method.
基金Supported by the National Natural Science Foundation of China.
文摘We present radio images of the compact steep spectrum (CSS) quasar 3C 286 acquired with the Very Large Array (VLA) at 8.4 and 22.5 GHz. The source exhibits a two-sided core-jet structure with a bright central component and two extended components one to the east (P.A. 100°) and another to the southwest (P.A. - 116°). From the compact core, an extension runs towards the southwest component up to - 0.7 arcsecond. The emission between the primary central component and the southwest component exhibits a knotty structure. A gradual change of the jet position angles from -135° to -120° in the inner southwest jet suggests a local bend. The position angle changes of the major eastern components E2 and El suggest that the eastern jet likely follows a curved trace. The bends in the jet trace may be associated with a relativistic precession or some interaction between the jet and the ambient matter. A mean spectral index of a22.58.4- 0.76 (Xv Va) is estimated for the core component. Steep spectra are also obtained for the extended southwest component (2.6', P.A. -116°) and eastern component (0.8', P.A. 100°), with a22.58.4-0.88 and a22.58.4-1.79, respectively. The radio morphologies and spectral index distributions suggest that the core seen in our images is likely to be the beamed inner jet while the real nucleus is dimmed by it beaming away from us.
基金the National Natural Science Foundation of China.
文摘We observed 1938-155, a broad line radio galaxy (BLRG), with the Very Large Array (VLA) at 90cm with an angular resolution of 6.8' × 4.0'. The source consists of two components separated by 4 arcsec (- 20kpc, for H0 = 65km s-1 Mpc-1, q0 = 0.5) along the SE-NW direction. Both components show steep-spectra with a similar spectral index α - 0.83 ± 0.07 (Sv ∝ v-α). The bright double components are surrounded by a low-brightness cocoon. The radio properties of the two bright components are consistent with the hot spots produced by twin jets. An upper limit of - 0.0008 for the core dominance parameter (R) is inferred, suggesting there is no prominent radio core in the source. Assuming a modest viewing angle 30f77, a jet velocity is estimated - 0.07 c, based on the jet to counter-jet brightness ratio (J). The lower limit in jet speed inferred is consistent with no Doppler beaming effect on the jet. The radio galaxy 1938-155 could be an exceptional BLRG with no prominent radio core or jet.
文摘The sanitary and environmental challenges posed by an ever growing economically and geographically diverse human population include the need for sustainable, inexpensive, scalable, and decentralized water treatment technologies that can supplement or replace conventional treatment methods. These challenges can be met by semiconductor photocatalysis, especially if the process is driven by visible light energy. Visible-light active (VLA) photocatalysis, as opposed to traditional energy-intensive and chemically driven disinfection methods such as ozonation, UV irradiation and chlorination, has the potential for achieving high disinfection efficiency with low energy consumption and no harmful by-products. This technology generates in-situ reactive oxygen species (ROS) such as H2O2, and?, without the need for chemicals addition. In turn, ROS are capable of penetrating cell walls and membranes of microorganisms, effectively inactivating them. Although multiple types of VLA photocatalysts have been used experimentally for disinfection of water, noble-metal-based photocatalysts have gained the most interest due to their surface plasma resonance (SPR) effect, which acts synergistically to increase the disinfection potential of the photocatalytic process. This paper is a review of the different types of noble-metal-based VLA photocatalysts used for water disinfection in different experimental settings, their synthesis procedures and disinfection mechanisms. It also discusses innovative approaches to overcome a major hurdle in photocatalysis, that is, the rapid recombination of the electron and hole pair, by including specific dopants into the structure of the photocatalyst.
