A two-bit phase shifter with distributed microelectromechanical system (MEMS) transmission line (DMTL) is developed,and a novel structure which be actuated by coplanar waveguide transmission line (CPW-actuation struct...A two-bit phase shifter with distributed microelectromechanical system (MEMS) transmission line (DMTL) is developed,and a novel structure which be actuated by coplanar waveguide transmission line (CPW-actuation structure) is proposed,which can reduce the actuation voltage significantly.The measured result,with actuation voltage less than 20V,0°/20.1°/41.9°/68.2° phase shift and -1.2dB insert loss at 20GHz,is demonstrated,and insertion loss/return loss is better than -1.8dB/-11dB from DC to 32GHz.The experimental results highlight the potential of a low-loss and broadband digital MEMS phase shifter on a high-permittivity substrate.展开更多
Based on the nonlinearization of Lax pairs, the Korteweg-de Vries （KdV） soliton hierarchy is decomposed into a family of finite-dimensional Hamiltonian systems, whose Liouville integrability is proved by means of th...Based on the nonlinearization of Lax pairs, the Korteweg-de Vries （KdV） soliton hierarchy is decomposed into a family of finite-dimensional Hamiltonian systems, whose Liouville integrability is proved by means of the elliptic coordinates. By applying the Abel-Jacobi coordinates on a Riemann surface of hyperelliptic curve, the resulting Hamiltonian flows as well as the KdV soliton hierarchy are ultimately reduced into linear superpositions, expressed by the Abel-Jacobi variables.展开更多
The interaction of DNA with cationic gemini suffactant trimethylene-1,3-bis （dodecyl dimethyl-ammonium bromide） （12-3-12） and anionic surfactant sodium dodecyl sulfate （SDS） mixed system has been investigated by...The interaction of DNA with cationic gemini suffactant trimethylene-1,3-bis （dodecyl dimethyl-ammonium bromide） （12-3-12） and anionic surfactant sodium dodecyl sulfate （SDS） mixed system has been investigated by measuring the fluorescence, zeta potential, UV-Vis spectrum, and circular dichroism. In the absence of SDS, owing to the electrostatic and hydrophobic interactions, 12-3-12 forms micelle-like structure on the DNA chain before the micellization in bulk phase. For the mixed system of 12-3-12 and SDS, the negative charges on SDS can compete against DNA to bind with cationic 12-3-12 because of the stronger interaction between oppositely charged surfactants, and thus, the catanionic mixed micelles are formed before the formation of DNA/12-3-12 complexes. There-after, the positive charges on the mixed micelles bind with DNA, and thus, the change of the zeta potential from negative to positive is distinctly different from the system without SDS. Meanwhile, the existence of SDS postpones the exclusion of ethidium bromide （EB） from DNA/EB complexes. The conformation of DNA undergoes a change from native B-form to chiral ψ-phase as binding with 12-3-12 process. Upon adding SDS to the DNA/12-3-12 complex solution, however, DNA is released to the bulk and the ψ-phase returns to B-form again.展开更多
A systematic study on the structures and electronic properties of copper clusters has been performed using the density functional theory. In the calculation, there are many isomers near the ground state for small copp...A systematic study on the structures and electronic properties of copper clusters has been performed using the density functional theory. In the calculation, there are many isomers near the ground state for small copper clusters. Our results show that the three-dimensional isomers of copper clusters start from Cu7 cluster and then show a tendency to form more compact structures. The results of the formation energy and the second derivative of binding energy with duster size show that besides N = 8, N =11 is also a magic number. Furthermore, it is the first time to find that the ground state of 11-atom clusters is a biplanar structure as same as the 13-atom cluster. The clear odd-even alternation as cluster size for the formation energy indicates the stability of electronic close shell existed in the range studied.展开更多
Recent and constant demands for greater power densities and smaller sizes of electronic systems have stimulated the growth of new designs of different passive heat transfer methods such as heat pipes. Particularly, OH...Recent and constant demands for greater power densities and smaller sizes of electronic systems have stimulated the growth of new designs of different passive heat transfer methods such as heat pipes. Particularly, OHPs （Oscillating Heat Pipes） are relatively novel devices, capable of removing high heat rates over long and short distances with not much temperature drop. This study concentrates on the design, building and assembling a test rig in order to analyse the flow pattern ofdeionised water through a 5 turns flat plate oscillating heat pipe under different heat inputs, which was made in the school of engineering and materials science of the Queen Mary University of London by two energy M.Sc. students. The filling ratio of the water is 40%. Furthermore an experimental study on the OHP thermal performance is carried out in order to examine the effects of different surface wet conditions： super hydrophilic, hydrophilic and cleaned brass. It is demonstrated the formation of liquid slugs and vapour plugs of the water along the channels. The experimental results showed that the hydrophilic surface tends to be more energy efficient. The heat transfer performance of the super-hydrophilic and hydrophilic is higher than brass by 5-12% and 15-20% respectively.展开更多
Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system （ASTP） with cationic surfactant （CTAB） and anionic surfactant （SDS）. Results indicate that ...Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system （ASTP） with cationic surfactant （CTAB） and anionic surfactant （SDS）. Results indicate that the region of ASTP is narrow and there is only a two-phase region of cationic surfactant. The increase in concentrations of NaBr and Na2SO4 are beneficial to the formation of ASTP. Theanine concentration in the bottom phase increases with increasing concentration of theanine, whereas the Partition coefficient and extraction rate only change a littlewhen the concentration of theanine is above 0.2 g.L-＇. With the increase of SDS concentration, the phase ratio and the partition coefficient decrease, while the extraction efficiency of theanine increases and the concentration of theanine changes a little in the range from 2.4/7.5 to 2.8/7.2 for SDS/CTAB ratio. The temperature has a notable ef- fect on the concentration of theanine in the bottom phase, partition coefficient and extraction rate of theanine. The increase of waste liquid decreases the phase ratio, increases the concentration and extraction rate of theanine in the bottom ohase, since the orotein and the saccharide enter the bottom nhase with theanine.展开更多
This study proposes a graphical user interface(GUI) based on an enhanced bacterial foraging optimization(EBFO) to find the optimal locations and sizing parameters of multi-type DFACTS in large-scale distribution syste...This study proposes a graphical user interface(GUI) based on an enhanced bacterial foraging optimization(EBFO) to find the optimal locations and sizing parameters of multi-type DFACTS in large-scale distribution systems.The proposed GUI based toolbox,allows the user to choose between single and multiple DFACTS allocations,followed by the type and number of them to be allocated.The EBFO is then applied to obtain optimal locations and ratings of the single and multiple DFACTS.This is found to be faster and provides more accurate results compared to the usual PSO and BFO.Results obtained with MATLAB/Simulink simulations are compared with PSO,BFO and enhanced BFO.It reveals that enhanced BFO shows quick convergence to reach the desired solution there by yielding superior solution quality.Simulation results concluded that the EBFO based multiple DFACTS allocation using DSSSC,APC and DSTATCOM is preferable to reduce power losses,improve load balancing and enhance voltage deviation index to 70%,38% and 132% respectively and also it can improve loading factor without additional power loss.展开更多
The adsorption state and catalytic properties of pepsin and acidic protease from microorganisms Asp. awamori and Asp. oryzae were studied in solid phase system （in presence of sorsilen, DEAE- and CM-cellulose）. Acco...The adsorption state and catalytic properties of pepsin and acidic protease from microorganisms Asp. awamori and Asp. oryzae were studied in solid phase system （in presence of sorsilen, DEAE- and CM-cellulose）. According to the results, adsorption capacity and catalytic activity of enzymes depend on the physical nature of surface groups of the solid phase. Changing the stability of enzymes in the system with solid phase is observed even the adsorption bond is less stable （in the case of DEAE- and CM-cellulose in acidic media）. Injection to the medium ethanol, surfactants, sodium chloride and changing the temperature of the incubation medium could prevent the negative effects of the solid phases. When sorsilen is used as solid phase, pepsin and acidic protease from Asp. awamori suffer from high surface inactivation. Various surfactants influence adsorption state of enzymes differently. Non-ionic surfactants （Triton X-100） prevent adsorption and restore catalytic properties of enzymes.展开更多
A 2D square lattice is studied. By using the continuum approximation, we set up the differential equations of motion for an arbitrary particle in the square lattice which subjects to an external periodic substrate pot...A 2D square lattice is studied. By using the continuum approximation, we set up the differential equations of motion for an arbitrary particle in the square lattice which subjects to an external periodic substrate potential. The exact solitary waves of the system are found for special cases. We conclude that the adhesive force f and the angle between propagation directions of upper and lower layers can affect these waves.展开更多
Close-coupling equation and anisotropic potential developed in our previous research are applied to HE-SHe （4He, 6He, 8He,10He） collision system, and partial cross sections （PCSs） at the incident energy of 40 me V...Close-coupling equation and anisotropic potential developed in our previous research are applied to HE-SHe （4He, 6He, 8He,10He） collision system, and partial cross sections （PCSs） at the incident energy of 40 me V are calculated. By analyzing the differences of these PCSs, change rules of PCSs with the increase of partial wave number, and with the change of the mass of isotope substitution helium atom are obtained. The results show that excitation PCSs converge faster than elastic PCSs for collision energy and each of systems considered here. Also excitation PCSs converge more rapidly for high-excited states. Tail effect is present only in elastic scattering and low-excited states but not in high- excited states. With the increase of the mass of isotope substitution helium atom, converging speed of elastic, total inelastic, and state-to-state excitation PCS slows down, and the maxima of these PCSs undergoes a regular change.展开更多
文摘A two-bit phase shifter with distributed microelectromechanical system (MEMS) transmission line (DMTL) is developed,and a novel structure which be actuated by coplanar waveguide transmission line (CPW-actuation structure) is proposed,which can reduce the actuation voltage significantly.The measured result,with actuation voltage less than 20V,0°/20.1°/41.9°/68.2° phase shift and -1.2dB insert loss at 20GHz,is demonstrated,and insertion loss/return loss is better than -1.8dB/-11dB from DC to 32GHz.The experimental results highlight the potential of a low-loss and broadband digital MEMS phase shifter on a high-permittivity substrate.
基金The project supported by National Natural Science Foundation of China under Grant No. 10471132 and the Special Foundation for.the State Key Basic Research Project ＂Nonlinear Science＂
文摘Based on the nonlinearization of Lax pairs, the Korteweg-de Vries （KdV） soliton hierarchy is decomposed into a family of finite-dimensional Hamiltonian systems, whose Liouville integrability is proved by means of the elliptic coordinates. By applying the Abel-Jacobi coordinates on a Riemann surface of hyperelliptic curve, the resulting Hamiltonian flows as well as the KdV soliton hierarchy are ultimately reduced into linear superpositions, expressed by the Abel-Jacobi variables.
基金Supported by the National Natural Science Foundation of China （20706013, 20736002）, Program for Changjiang Scholars and Innovative Research Team in University （IRT0721）, the 111 Project （B08021） and National University of Singapore.
文摘The interaction of DNA with cationic gemini suffactant trimethylene-1,3-bis （dodecyl dimethyl-ammonium bromide） （12-3-12） and anionic surfactant sodium dodecyl sulfate （SDS） mixed system has been investigated by measuring the fluorescence, zeta potential, UV-Vis spectrum, and circular dichroism. In the absence of SDS, owing to the electrostatic and hydrophobic interactions, 12-3-12 forms micelle-like structure on the DNA chain before the micellization in bulk phase. For the mixed system of 12-3-12 and SDS, the negative charges on SDS can compete against DNA to bind with cationic 12-3-12 because of the stronger interaction between oppositely charged surfactants, and thus, the catanionic mixed micelles are formed before the formation of DNA/12-3-12 complexes. There-after, the positive charges on the mixed micelles bind with DNA, and thus, the change of the zeta potential from negative to positive is distinctly different from the system without SDS. Meanwhile, the existence of SDS postpones the exclusion of ethidium bromide （EB） from DNA/EB complexes. The conformation of DNA undergoes a change from native B-form to chiral ψ-phase as binding with 12-3-12 process. Upon adding SDS to the DNA/12-3-12 complex solution, however, DNA is released to the bulk and the ψ-phase returns to B-form again.
文摘A systematic study on the structures and electronic properties of copper clusters has been performed using the density functional theory. In the calculation, there are many isomers near the ground state for small copper clusters. Our results show that the three-dimensional isomers of copper clusters start from Cu7 cluster and then show a tendency to form more compact structures. The results of the formation energy and the second derivative of binding energy with duster size show that besides N = 8, N =11 is also a magic number. Furthermore, it is the first time to find that the ground state of 11-atom clusters is a biplanar structure as same as the 13-atom cluster. The clear odd-even alternation as cluster size for the formation energy indicates the stability of electronic close shell existed in the range studied.
文摘Recent and constant demands for greater power densities and smaller sizes of electronic systems have stimulated the growth of new designs of different passive heat transfer methods such as heat pipes. Particularly, OHPs （Oscillating Heat Pipes） are relatively novel devices, capable of removing high heat rates over long and short distances with not much temperature drop. This study concentrates on the design, building and assembling a test rig in order to analyse the flow pattern ofdeionised water through a 5 turns flat plate oscillating heat pipe under different heat inputs, which was made in the school of engineering and materials science of the Queen Mary University of London by two energy M.Sc. students. The filling ratio of the water is 40%. Furthermore an experimental study on the OHP thermal performance is carried out in order to examine the effects of different surface wet conditions： super hydrophilic, hydrophilic and cleaned brass. It is demonstrated the formation of liquid slugs and vapour plugs of the water along the channels. The experimental results showed that the hydrophilic surface tends to be more energy efficient. The heat transfer performance of the super-hydrophilic and hydrophilic is higher than brass by 5-12% and 15-20% respectively.
基金Supported by the Fundamental Research Funds for the Central Universities(JUSRP11205)
文摘Extraction of theanine from waste liquid of tea polyphenol production was studied in aqueous surfactanttwo-phase system （ASTP） with cationic surfactant （CTAB） and anionic surfactant （SDS）. Results indicate that the region of ASTP is narrow and there is only a two-phase region of cationic surfactant. The increase in concentrations of NaBr and Na2SO4 are beneficial to the formation of ASTP. Theanine concentration in the bottom phase increases with increasing concentration of theanine, whereas the Partition coefficient and extraction rate only change a littlewhen the concentration of theanine is above 0.2 g.L-＇. With the increase of SDS concentration, the phase ratio and the partition coefficient decrease, while the extraction efficiency of theanine increases and the concentration of theanine changes a little in the range from 2.4/7.5 to 2.8/7.2 for SDS/CTAB ratio. The temperature has a notable ef- fect on the concentration of theanine in the bottom phase, partition coefficient and extraction rate of theanine. The increase of waste liquid decreases the phase ratio, increases the concentration and extraction rate of theanine in the bottom ohase, since the orotein and the saccharide enter the bottom nhase with theanine.
基金Project supported by Borujerd Branch,Islamic Azad University,Iran
文摘This study proposes a graphical user interface(GUI) based on an enhanced bacterial foraging optimization(EBFO) to find the optimal locations and sizing parameters of multi-type DFACTS in large-scale distribution systems.The proposed GUI based toolbox,allows the user to choose between single and multiple DFACTS allocations,followed by the type and number of them to be allocated.The EBFO is then applied to obtain optimal locations and ratings of the single and multiple DFACTS.This is found to be faster and provides more accurate results compared to the usual PSO and BFO.Results obtained with MATLAB/Simulink simulations are compared with PSO,BFO and enhanced BFO.It reveals that enhanced BFO shows quick convergence to reach the desired solution there by yielding superior solution quality.Simulation results concluded that the EBFO based multiple DFACTS allocation using DSSSC,APC and DSTATCOM is preferable to reduce power losses,improve load balancing and enhance voltage deviation index to 70%,38% and 132% respectively and also it can improve loading factor without additional power loss.
文摘The adsorption state and catalytic properties of pepsin and acidic protease from microorganisms Asp. awamori and Asp. oryzae were studied in solid phase system （in presence of sorsilen, DEAE- and CM-cellulose）. According to the results, adsorption capacity and catalytic activity of enzymes depend on the physical nature of surface groups of the solid phase. Changing the stability of enzymes in the system with solid phase is observed even the adsorption bond is less stable （in the case of DEAE- and CM-cellulose in acidic media）. Injection to the medium ethanol, surfactants, sodium chloride and changing the temperature of the incubation medium could prevent the negative effects of the solid phases. When sorsilen is used as solid phase, pepsin and acidic protease from Asp. awamori suffer from high surface inactivation. Various surfactants influence adsorption state of enzymes differently. Non-ionic surfactants （Triton X-100） prevent adsorption and restore catalytic properties of enzymes.
基金supported by National Natural Science Foundation of China under Grant No. 10575082the Natural Science Foundation of Gansu Province under Grant No. 3ZS061-A25-013the Natural Science Foundation of Northwest Normal University under Grant No. NWNU-KJCXGC-03-17
文摘A 2D square lattice is studied. By using the continuum approximation, we set up the differential equations of motion for an arbitrary particle in the square lattice which subjects to an external periodic substrate potential. The exact solitary waves of the system are found for special cases. We conclude that the adhesive force f and the angle between propagation directions of upper and lower layers can affect these waves.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10676025 and 10974139
文摘Close-coupling equation and anisotropic potential developed in our previous research are applied to HE-SHe （4He, 6He, 8He,10He） collision system, and partial cross sections （PCSs） at the incident energy of 40 me V are calculated. By analyzing the differences of these PCSs, change rules of PCSs with the increase of partial wave number, and with the change of the mass of isotope substitution helium atom are obtained. The results show that excitation PCSs converge faster than elastic PCSs for collision energy and each of systems considered here. Also excitation PCSs converge more rapidly for high-excited states. Tail effect is present only in elastic scattering and low-excited states but not in high- excited states. With the increase of the mass of isotope substitution helium atom, converging speed of elastic, total inelastic, and state-to-state excitation PCS slows down, and the maxima of these PCSs undergoes a regular change.
