In this paper, a two level finite difference scheme of Crank-Nicholson type is constructed and used to numerically investigate nonlinear temperature distribution in biological tissues described by bioheat transfer equ...In this paper, a two level finite difference scheme of Crank-Nicholson type is constructed and used to numerically investigate nonlinear temperature distribution in biological tissues described by bioheat transfer equation of Pennes’ type. For the equation under consideration, the thermal conductivity is either depth-dependent or tem-perature-dependent, while blood perfusion is temperature-dependent. In both cases of depth- dependent and temperature-dependent thermal conductivity, it is shown that blood perfusion decreases the temperature of the living tissue. Our numerical simulations show that neither the localization nor the magnitude of peak tempera-ture is affected by surface temperature;however, the width of peak temperature increases with surface temperature.展开更多
The new polydentate mixed-N,P,O chiral ligands have been synthesized by the condensation of bis（o-formylphenyl）- phenylphosphane and R-phenylglycinol in CHCl_3,and fully characterized by IR,NMR and EIMS spectra.Thes...The new polydentate mixed-N,P,O chiral ligands have been synthesized by the condensation of bis（o-formylphenyl）- phenylphosphane and R-phenylglycinol in CHCl_3,and fully characterized by IR,NMR and EIMS spectra.These ligands were employed with a simple Ni complex Ni（PPh_s）_2Cl_2 in situ as catalytic systems for asymmetric transfer hydrogenation of ketones,and the corresponding optical alcohols were obtained with up to 84%ee under mild conditions.展开更多
Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the...Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.展开更多
The population transfer in a ladder-type atomic system driven by linearly polarized sech-shape femtosecond laser pulses is investigated by numerically solving Schr6dinger equation without including the rotating wave a...The population transfer in a ladder-type atomic system driven by linearly polarized sech-shape femtosecond laser pulses is investigated by numerically solving Schr6dinger equation without including the rotating wave approximation （RWA）. It is shown that population transfer is mainly determined by the Rabi frequency （strength） of the driving laser field and the chirp rate, and that the ratio of the dipole moments and the pulse width also have a prominent effect on the population transfer. By choosing appropriate values of the above parameters, complete population transfer can be realized.展开更多
Type-A spermatogonia first appear at between 3-7 d postnatally in mice and are the only immortalized diploid cells that reproduce in adulthood in these animals. In our current study, we explored the feasibility of pro...Type-A spermatogonia first appear at between 3-7 d postnatally in mice and are the only immortalized diploid cells that reproduce in adulthood in these animals. In our current study, we explored the feasibility of producing stable transgenic mice using these cells. Enhanced pEGFP-N1 plasmids were suspended in ExGen500 transfection reagent and injected at different angles into the testes of 7-d-old male ICR mice. The resulting type-A spermatogonia-mediated gene transfer （TASMGT） mice were then mated with normal females at different stages of sexual maturity （6, 12, and 24 wk）. The integration and expression of the introduced EGFP gene was evaluated in the F1 transgenic offspring by PCR and Southern blotting analysis. The foreign gene integration rates for a low-dose group （15 μL gene suspension injected into each testis） and a high-dose group （30 μL suspensions injected） at the three stages of female sexual maturity tested were 11.76% （2/17）, 14.29% （3/21）, and 11.11% （2/18）, and 5% （1/20）, 5.56% （1/18）, and 0 （0/17）, respectively. The average integration rates for these two dose groups were 12.5% （7/56） and 3.64% （2/55）, respectively, which was a significant difference （P0.05）. Semi-quantitative RT-PCR analysis further showed that the introduced GFP gene was expressed in 3/9 integration mice. In addition, GFP expression was observed in the sperm cells from the TASMGT mice, and also in the embryos and F2 pups from the F1 generation transgenic mice. Hence, although the foreign gene integration rate for TASMGT is not high and the transgenic offspring show as yet unexplained defects, our results indicate that this method is a potentially feasible and reproducible new approach to creating transgenic mice.展开更多
Two species of radishes, Raphanus sativus and Raphanus raphanistrum, were grown in the laboratory in the same substrate consisting of a smectite-type clay, which was watered at the beginning of the experience with 50 ...Two species of radishes, Raphanus sativus and Raphanus raphanistrum, were grown in the laboratory in the same substrate consisting of a smectite-type clay, which was watered at the beginning of the experience with 50 ml of a solution containing either none or 1000, 2000 or 4000 mg/L of AgNO3, respectively. Occurrence of the toxic metal in the substrate outlines higher element uptakes by the cultivated species Raphanus sativus than by the wild species Raphanus raphanistrum, except for the highest degree of Ag pollution. After a one-month growth in the Ag-polluted substrate, Raphanus sativus was depleted in most of the major, trace and rare-earth elements, except for Al, Fe, Th, Ag and U that increased in the radishes from substrate polluted by 2000 mg/L of AgNO3, and Sr, Co, Ni, U and Ag that increased in the radishes from substrate polluted by 4000 mg/L of AgNO3. Raphanus raphanistrum was enriched in all elements except Si, Na, Rb and K in the polluted substrate. The uptake was monitored by a cation-exchange process in the rhy-zosphere between mineral particles and the watering solution in the presence of various enzymes with specific activities that induced a variable uptake with the REEs being even fractionated. These activities most probably depend on combined factors, such as the plant species, and the chemical and physical properties of the substrate. The results obtained here reveal also that accumulation of nutrient elements and others in the plants is not uniform at a given Ag pollution of the substrate and therefore at a given Ag contamination in the same plant species.展开更多
Based on a thorough theory of the Artin transfer homomorphism from a group G to the abelianization of a subgroup of finite index , and its connection with the permutation representation and the monomial representation...Based on a thorough theory of the Artin transfer homomorphism from a group G to the abelianization of a subgroup of finite index , and its connection with the permutation representation and the monomial representation of G, the Artin pattern , which consists of families , resp. , of transfer targets, resp. transfer kernels, is defined for the vertices of any descendant tree T of finite p-groups. It is endowed with partial order relations and , which are compatible with the parent-descendant relation of the edges of the tree T. The partial order enables termination criteria for the p-group generation algorithm which can be used for searching and identifying a finite p-group G, whose Artin pattern is known completely or at least partially, by constructing the descendant tree with the abelianization of G as its root. An appendix summarizes details concerning induced homomorphisms between quotient groups, which play a crucial role in establishing the natural partial order on Artin patterns and explaining the stabilization, resp. polarization, of their components in descendant trees T of finite p-groups.展开更多
A modelling study is performed to compare the plasma flow and heat transfer characteristics of low-power arc-heated thrusters （arcjets） for three different propellants： hydrogen, nitrogen and argon. The all-speed S...A modelling study is performed to compare the plasma flow and heat transfer characteristics of low-power arc-heated thrusters （arcjets） for three different propellants： hydrogen, nitrogen and argon. The all-speed SIMPLE algorithm is employed to solve the governing equations, which take into account the effects of compressibility, Lorentz force and Joule heating, as well as the temperature- and pressure-dependence of the gas properties. The temperature, velocity and Mach number distributions calculated within the thruster nozzle obtained with different propellant gases are compared for the same thruster structure, dimensions, inlet-gas stagnant pressure and arc currents. The temperature distributions in the solid region of the anode-nozzle wall are also given. It is found that the flow and energy conversion processes in the thruster nozzle show many similar features for all three propellants. For example, the propellant is heated mainly in the near-cathode and constrictor region, with the highest plasma temperature appearing near the cathode tip; the flow transition from the subsonic to supersonic regime occurs within the constrictor region; the highest axial velocity appears inside the nozzle; and most of the input propellant flows towards the thruster exit through the cooler gas region near the anode-nozzle wall. However, since the properties of hydrogen, nitrogen and argon, especially their molecular weights, specific enthMpies and thermal conductivities, are different, there are appreciable differences in arcjet performance. For example, compared to the other two propellants, the hydrogen arcjet thruster shows a higher plasma temperature in the arc region, and higher axial velocity but lower temperature at the thruster exit. Correspondingly, the hydrogen arcjet thruster has the highest specific impulse and arc voltage for the same inlet stagnant pressure and arc current. The predictions of the modelling are compared favourably with available experimental results.展开更多
Quantum teleportation with entanglement channels and a series of two-qubit SWAP gates between the nearestneighbor qubits are usually utilized to achieve the transfers of unknown quantum state from the sender to the di...Quantum teleportation with entanglement channels and a series of two-qubit SWAP gates between the nearestneighbor qubits are usually utilized to achieve the transfers of unknown quantum state from the sender to the distant receiver. In this paper, by simplifying the usual SWAP gates we propose an approach to speed up the transmissions of unknown quantum information, specifically including the single-qubit unknown state and two-qubit unknown entangled ones,by a series of entangling and disentangling operations between the remote qubits with distant interactions. The generic proposal is demonstrated specifically with experimentally-existing Ising-type quantum channels without transverse interaction; liquid NMR-molecules driven by global radio frequency electromagnetic pulses and capacitively-coupled Josephson circuits driven by local microwave pulses. The proposal should be particularly useful to set up the connections between the distant qubits in a chip of quantum computing.展开更多
In recent years, the new type of tumble waste dryer has been promoted and developed. Heat generation through phase transition is an environmental, friendly and efficient heat transfer drying method. In order to know u...In recent years, the new type of tumble waste dryer has been promoted and developed. Heat generation through phase transition is an environmental, friendly and efficient heat transfer drying method. In order to know under what conditions the water vapor has higher heat transfer efficiency in the semi-circular cylinder and more sufficient liquid phase transition, and under what conditions the quantity of heat transferred can be exactly controlled, we carried out relevant work. Based on the analysis of two-phase heat transfer of rotating body, a three-dimension model of garbage dryer is established. Then, the commercial CFD software ANSYS Fluent is used to simulate the two-phase flow in the semi-circular cylinder, and the simulation calculation is carried out. Finally, the theoretical calculation results are verified by experiments. Calculated by the simulation results analysis: according to the industrial use of setting conditions, simulation calculation results can achieve convergence, namely water vapor through the pipe wall heat conduction. Finally condense into liquid water, and to ensure that the liquid cavity in the body has a higher volume fraction, water vapor phase change rate is of more than 90%, the Nusselt number of the heat transfer surface is 60 to 300.展开更多
The propagation of a Bleustein-Gulyaev （B-G） type wave in a structure consisting of multiple layers and a half-space of porous piezoelectric materials is theoreti- cally studied. The solutions of the problem in term...The propagation of a Bleustein-Gulyaev （B-G） type wave in a structure consisting of multiple layers and a half-space of porous piezoelectric materials is theoreti- cally studied. The solutions of the problem in terms of the mechanical displacements and electric potential functions are obtained for each layer and the half-space. The dispersion equation is obtained for electrically open and shorted boundary conditions by use of the transfer matrix method. A peculiar kind of B-G waves is investigated, which can propagate only in the layer over the half-space. The relationship between the piezoelectric constants and the dielectric constants is found for the existence of a peculiar kind of propagation modes. The numerical results in terms of the phase velocity and the electromechanical coupling factor with different thicknesses of the layer stack are presented.展开更多
H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization （ATRP）. Macroinitiators prepared by the esterification between poly（ethylene ox...H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization （ATRP）. Macroinitiators prepared by the esterification between poly（ethylene oxide） （PEG） and 2,2-dichloroacetyl chloride were utilized to initiate the polymerization of 6-[4-（4-ethoxyphenylazo）phenoxy]hexyl rnethacrylate （M6C）. The resulting macroinitiators and block copolymers were characterized by ^1H NMR, gel permeation chromatography （GPC）. Polarizing optical microscopy （POM） and differential scanning calorimetry （DSC） preliminarily revealed the liquid crystalline property of these block copolymers. This series of liquid crystalline block copolymers are promising in some areas, such as optical data storage, optical switch, and molecular devices.展开更多
Hot plate forming using a cell-typed die is a process for forming a large thick plate with a spherical shape for the manufacture of a large spherical LNG tank.Cell-typed upper and lower dies made of a framework of ste...Hot plate forming using a cell-typed die is a process for forming a large thick plate with a spherical shape for the manufacture of a large spherical LNG tank.Cell-typed upper and lower dies made of a framework of steel plates fitted to make a grid pattern are used in this process,and an air-cooling device is separately installed inside the lower die.A finite element analysis (FEA) technique was developed,which included hot forming,air flow,cooling and thermal deformation analysis for the hot plate forming process using the cell-typed die.Further,the convective and interface heat transfer coefficients were used to reproduce analytically the effects of the cooling device in the hot plate forming analysis.A small-scale model test of the process was conducted to verify the FEA technique.The analysis results show that the curvature of the final plate agrees well with that of the designed experiment within a maximum relative error of 0.03% at the corner of the plate.展开更多
文摘In this paper, a two level finite difference scheme of Crank-Nicholson type is constructed and used to numerically investigate nonlinear temperature distribution in biological tissues described by bioheat transfer equation of Pennes’ type. For the equation under consideration, the thermal conductivity is either depth-dependent or tem-perature-dependent, while blood perfusion is temperature-dependent. In both cases of depth- dependent and temperature-dependent thermal conductivity, it is shown that blood perfusion decreases the temperature of the living tissue. Our numerical simulations show that neither the localization nor the magnitude of peak tempera-ture is affected by surface temperature;however, the width of peak temperature increases with surface temperature.
基金the National Natural Science Foundation of China(No21173176)the Natural Science Foundation of Guangxi Province of China(No0991016)for the financial support of this work
文摘The new polydentate mixed-N,P,O chiral ligands have been synthesized by the condensation of bis（o-formylphenyl）- phenylphosphane and R-phenylglycinol in CHCl_3,and fully characterized by IR,NMR and EIMS spectra.These ligands were employed with a simple Ni complex Ni（PPh_s）_2Cl_2 in situ as catalytic systems for asymmetric transfer hydrogenation of ketones,and the corresponding optical alcohols were obtained with up to 84%ee under mild conditions.
文摘Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12. The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.
基金supported by National Basic Research Program of China (Grant No 2006CB806003)the Natural Science Foundation of Shandong Province,China (Grant No Y2006A21)+1 种基金the National Natural Science Foundation of China (Grant No 10675076)State Key Laboratory of High Field Laser Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,China
文摘The population transfer in a ladder-type atomic system driven by linearly polarized sech-shape femtosecond laser pulses is investigated by numerically solving Schr6dinger equation without including the rotating wave approximation （RWA）. It is shown that population transfer is mainly determined by the Rabi frequency （strength） of the driving laser field and the chirp rate, and that the ratio of the dipole moments and the pulse width also have a prominent effect on the population transfer. By choosing appropriate values of the above parameters, complete population transfer can be realized.
基金supported by the National Transgenic Breeding Project (2008ZX08010-004)the National Natural Science Foundation of China (30830080)+1 种基金the National 973 Program of China (G2006CB102105,2009CB941604)the National 863 Program of China (20060110Z1039, 2008AA10Z143)
文摘Type-A spermatogonia first appear at between 3-7 d postnatally in mice and are the only immortalized diploid cells that reproduce in adulthood in these animals. In our current study, we explored the feasibility of producing stable transgenic mice using these cells. Enhanced pEGFP-N1 plasmids were suspended in ExGen500 transfection reagent and injected at different angles into the testes of 7-d-old male ICR mice. The resulting type-A spermatogonia-mediated gene transfer （TASMGT） mice were then mated with normal females at different stages of sexual maturity （6, 12, and 24 wk）. The integration and expression of the introduced EGFP gene was evaluated in the F1 transgenic offspring by PCR and Southern blotting analysis. The foreign gene integration rates for a low-dose group （15 μL gene suspension injected into each testis） and a high-dose group （30 μL suspensions injected） at the three stages of female sexual maturity tested were 11.76% （2/17）, 14.29% （3/21）, and 11.11% （2/18）, and 5% （1/20）, 5.56% （1/18）, and 0 （0/17）, respectively. The average integration rates for these two dose groups were 12.5% （7/56） and 3.64% （2/55）, respectively, which was a significant difference （P0.05）. Semi-quantitative RT-PCR analysis further showed that the introduced GFP gene was expressed in 3/9 integration mice. In addition, GFP expression was observed in the sperm cells from the TASMGT mice, and also in the embryos and F2 pups from the F1 generation transgenic mice. Hence, although the foreign gene integration rate for TASMGT is not high and the transgenic offspring show as yet unexplained defects, our results indicate that this method is a potentially feasible and reproducible new approach to creating transgenic mice.
文摘Two species of radishes, Raphanus sativus and Raphanus raphanistrum, were grown in the laboratory in the same substrate consisting of a smectite-type clay, which was watered at the beginning of the experience with 50 ml of a solution containing either none or 1000, 2000 or 4000 mg/L of AgNO3, respectively. Occurrence of the toxic metal in the substrate outlines higher element uptakes by the cultivated species Raphanus sativus than by the wild species Raphanus raphanistrum, except for the highest degree of Ag pollution. After a one-month growth in the Ag-polluted substrate, Raphanus sativus was depleted in most of the major, trace and rare-earth elements, except for Al, Fe, Th, Ag and U that increased in the radishes from substrate polluted by 2000 mg/L of AgNO3, and Sr, Co, Ni, U and Ag that increased in the radishes from substrate polluted by 4000 mg/L of AgNO3. Raphanus raphanistrum was enriched in all elements except Si, Na, Rb and K in the polluted substrate. The uptake was monitored by a cation-exchange process in the rhy-zosphere between mineral particles and the watering solution in the presence of various enzymes with specific activities that induced a variable uptake with the REEs being even fractionated. These activities most probably depend on combined factors, such as the plant species, and the chemical and physical properties of the substrate. The results obtained here reveal also that accumulation of nutrient elements and others in the plants is not uniform at a given Ag pollution of the substrate and therefore at a given Ag contamination in the same plant species.
文摘Based on a thorough theory of the Artin transfer homomorphism from a group G to the abelianization of a subgroup of finite index , and its connection with the permutation representation and the monomial representation of G, the Artin pattern , which consists of families , resp. , of transfer targets, resp. transfer kernels, is defined for the vertices of any descendant tree T of finite p-groups. It is endowed with partial order relations and , which are compatible with the parent-descendant relation of the edges of the tree T. The partial order enables termination criteria for the p-group generation algorithm which can be used for searching and identifying a finite p-group G, whose Artin pattern is known completely or at least partially, by constructing the descendant tree with the abelianization of G as its root. An appendix summarizes details concerning induced homomorphisms between quotient groups, which play a crucial role in establishing the natural partial order on Artin patterns and explaining the stabilization, resp. polarization, of their components in descendant trees T of finite p-groups.
基金supported by National Natural Science Foundation of China (Nos.50836007, 10921062)
文摘A modelling study is performed to compare the plasma flow and heat transfer characteristics of low-power arc-heated thrusters （arcjets） for three different propellants： hydrogen, nitrogen and argon. The all-speed SIMPLE algorithm is employed to solve the governing equations, which take into account the effects of compressibility, Lorentz force and Joule heating, as well as the temperature- and pressure-dependence of the gas properties. The temperature, velocity and Mach number distributions calculated within the thruster nozzle obtained with different propellant gases are compared for the same thruster structure, dimensions, inlet-gas stagnant pressure and arc currents. The temperature distributions in the solid region of the anode-nozzle wall are also given. It is found that the flow and energy conversion processes in the thruster nozzle show many similar features for all three propellants. For example, the propellant is heated mainly in the near-cathode and constrictor region, with the highest plasma temperature appearing near the cathode tip; the flow transition from the subsonic to supersonic regime occurs within the constrictor region; the highest axial velocity appears inside the nozzle; and most of the input propellant flows towards the thruster exit through the cooler gas region near the anode-nozzle wall. However, since the properties of hydrogen, nitrogen and argon, especially their molecular weights, specific enthMpies and thermal conductivities, are different, there are appreciable differences in arcjet performance. For example, compared to the other two propellants, the hydrogen arcjet thruster shows a higher plasma temperature in the arc region, and higher axial velocity but lower temperature at the thruster exit. Correspondingly, the hydrogen arcjet thruster has the highest specific impulse and arc voltage for the same inlet stagnant pressure and arc current. The predictions of the modelling are compared favourably with available experimental results.
基金partly supported by the National Natural Science Foundation of China(Grant No.U1330201)
文摘Quantum teleportation with entanglement channels and a series of two-qubit SWAP gates between the nearestneighbor qubits are usually utilized to achieve the transfers of unknown quantum state from the sender to the distant receiver. In this paper, by simplifying the usual SWAP gates we propose an approach to speed up the transmissions of unknown quantum information, specifically including the single-qubit unknown state and two-qubit unknown entangled ones,by a series of entangling and disentangling operations between the remote qubits with distant interactions. The generic proposal is demonstrated specifically with experimentally-existing Ising-type quantum channels without transverse interaction; liquid NMR-molecules driven by global radio frequency electromagnetic pulses and capacitively-coupled Josephson circuits driven by local microwave pulses. The proposal should be particularly useful to set up the connections between the distant qubits in a chip of quantum computing.
文摘In recent years, the new type of tumble waste dryer has been promoted and developed. Heat generation through phase transition is an environmental, friendly and efficient heat transfer drying method. In order to know under what conditions the water vapor has higher heat transfer efficiency in the semi-circular cylinder and more sufficient liquid phase transition, and under what conditions the quantity of heat transferred can be exactly controlled, we carried out relevant work. Based on the analysis of two-phase heat transfer of rotating body, a three-dimension model of garbage dryer is established. Then, the commercial CFD software ANSYS Fluent is used to simulate the two-phase flow in the semi-circular cylinder, and the simulation calculation is carried out. Finally, the theoretical calculation results are verified by experiments. Calculated by the simulation results analysis: according to the industrial use of setting conditions, simulation calculation results can achieve convergence, namely water vapor through the pipe wall heat conduction. Finally condense into liquid water, and to ensure that the liquid cavity in the body has a higher volume fraction, water vapor phase change rate is of more than 90%, the Nusselt number of the heat transfer surface is 60 to 300.
基金Project supported by the Council of Scientific and Industrial Research of India(No.09/105(0162)/2008-EMR-I)
文摘The propagation of a Bleustein-Gulyaev （B-G） type wave in a structure consisting of multiple layers and a half-space of porous piezoelectric materials is theoreti- cally studied. The solutions of the problem in terms of the mechanical displacements and electric potential functions are obtained for each layer and the half-space. The dispersion equation is obtained for electrically open and shorted boundary conditions by use of the transfer matrix method. A peculiar kind of B-G waves is investigated, which can propagate only in the layer over the half-space. The relationship between the piezoelectric constants and the dielectric constants is found for the existence of a peculiar kind of propagation modes. The numerical results in terms of the phase velocity and the electromechanical coupling factor with different thicknesses of the layer stack are presented.
基金financial support from the National Natural Science Foundation of China(No.20134020)the Science Research Fund of the Chinese Ministry of Education(No.104005)the Science Research Fund of Shandong Provincial Education Department of China(No.105D11).
文摘H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization （ATRP）. Macroinitiators prepared by the esterification between poly（ethylene oxide） （PEG） and 2,2-dichloroacetyl chloride were utilized to initiate the polymerization of 6-[4-（4-ethoxyphenylazo）phenoxy]hexyl rnethacrylate （M6C）. The resulting macroinitiators and block copolymers were characterized by ^1H NMR, gel permeation chromatography （GPC）. Polarizing optical microscopy （POM） and differential scanning calorimetry （DSC） preliminarily revealed the liquid crystalline property of these block copolymers. This series of liquid crystalline block copolymers are promising in some areas, such as optical data storage, optical switch, and molecular devices.
基金Project(2010-0008-277)supported by the NCRC(National Core Research Center)Program through the National Research Foundation of Korea,funded by the Ministry of Education,Science,and TechnologyProject supported by R&D for Technology Development Program of Ministry of Knowledge Economy,Korea
文摘Hot plate forming using a cell-typed die is a process for forming a large thick plate with a spherical shape for the manufacture of a large spherical LNG tank.Cell-typed upper and lower dies made of a framework of steel plates fitted to make a grid pattern are used in this process,and an air-cooling device is separately installed inside the lower die.A finite element analysis (FEA) technique was developed,which included hot forming,air flow,cooling and thermal deformation analysis for the hot plate forming process using the cell-typed die.Further,the convective and interface heat transfer coefficients were used to reproduce analytically the effects of the cooling device in the hot plate forming analysis.A small-scale model test of the process was conducted to verify the FEA technique.The analysis results show that the curvature of the final plate agrees well with that of the designed experiment within a maximum relative error of 0.03% at the corner of the plate.
