in recent years research investigating various health benefits of Taiji practice has markedly increased. Despite this growing scientific interest, essential questions such as to what extent a Taiji course may exert no...in recent years research investigating various health benefits of Taiji practice has markedly increased. Despite this growing scientific interest, essential questions such as to what extent a Taiji course may exert noticeable effects in participants＇ everyday life, what these effects are, and how and where potential transfer effects occur, have hardly been considered. The aim of our study was to explore transfer effects from a Taiji course into participants＇ daily lives. METHODS： We conducted a longitudinal observational study in 45 healthy participants at the end of their three-month Taiji beginner course （tpl） and at two months （tp2） as well as one year after course completion （tp3）. Participants were asked to report their Taiji practice behavior at all time points, as well as to rate and describe perceived transfer effects of Taiji course contents on their daily life at tpl and tp3. RESULTS： Transfer effects were reported by 91.1% of all respondents after course completion （tpl） and persisted in 73.3% at the one-year follow-up assessment （tp3）, counting ＂increase of self-efficacy＂, ＂improvement of stress management＂, and ＂increase of body awareness＂ as the most frequently mentioned effects. Transfer effects predominantly occurred in participants＇ work and social environments, as well as during everyday activities in public areas. While self- reliant Taiji practice frequency significantly decreased from 82.2% at tpl to 55.6% at tp3 （P 〈 0.001）, the magnitude of self-reported transfer effects did not （P = 0.35）. As explorative analyses revealed, regular Taiji course attendance was highly correlated with stronger transfer effects at tpl （r = 0.51; P 〈 0.001） and tp3 （r = 0.35; P = 0.020）. Participants reporting high self-reliant Taiji practice frequency at tp2 were likely to maintain a regular practice routine at tp3 （r = 0.42; P 〈 0.004）, whereas self-reliant practice frequency and transfer effects at tpl were positively correlated with self-reliant practice frequency at tp3 on a trend level （r 〈 0.27; P 〉 0.08）. CONCLUSION： Our data underline the importance of regular course participation for pronounced and long lasting transfer effects into participants＇ everyday life. We discuss that several context and process-related aspects of a Taiji intervention are potentially relevant factors for enhancement of transfer effect.展开更多
SiGe based alloy is a promising medium-high temperature thermoelectric material that has been applied in the field of aerospace exploration.So far,utilizing the second phase to promote the scattering of phonons is a c...SiGe based alloy is a promising medium-high temperature thermoelectric material that has been applied in the field of aerospace exploration.So far,utilizing the second phase to promote the scattering of phonons is a common way to improve the thermoelectric performance of SiGe based alloy,but this often deteriorates the electrical properties.In this study,the Si_(80)Ge_(20)P_(1)/CoSi_(2) composites have been prepared by mechanical alloying and spark plasma sintering,and the content of cobalt silicide(CoSi_(2))nanoparticles have been manipulated.Since the CoSi_(2) nanoparticles possess higher carrier concentration and smaller work function than the Si_(80)Ge_(20)P_(1) matrix,the carrier concentrations of composites have been pushed up due the charge transfer effect.Meanwhile,the formation of nano-sized phase interfaces and stacking faults in the composites has enhanced the scattering of low-frequency phonons.As a result,the optimal power factor of 3.41 mW·m^(-1),K^(-2) and thermal conductivity of 2.29 W·m^(-1),K^(-1) have been achieved,and the corresponding zT reaches up to 1.3 in the Si_(80)Ge_(20)P_(1)+0.5%CoSi_(2)(in mole)composite at 873 K.This work provides a new idea for developing the performance of SiGe based alloy.展开更多
A heat transfer model for three-fluid separated heat pipe exchanger was analyzed,and the temperature transfer matrix for general three-fluid separated heat exchanger working in parallel-flow or counter-flow mode was o...A heat transfer model for three-fluid separated heat pipe exchanger was analyzed,and the temperature transfer matrix for general three-fluid separated heat exchanger working in parallel-flow or counter-flow mode was obtained.It was found that the forms of temperature transfer matrix are similar for heat pipe rows with equal or different heat transfer surface area.Furthermore,by using the temperature transfer matrix of the heat pipe exchanger,the relationship between heat transfer effectiveness θ 1,θ 2 and M,NTU,U,Δt i were derived for the exchanger operating in parallel-flow or counter-flow mode,and a simple special example was adopted to demonstrate the correctness of these relationships.展开更多
As the native language transfer inevitably exerts definite influences on English study,the paper is to give a more detailed analysis to the positive and negative effects in one's L2 learning.In English teaching,th...As the native language transfer inevitably exerts definite influences on English study,the paper is to give a more detailed analysis to the positive and negative effects in one's L2 learning.In English teaching,the full use of the positive effect of the native language transfer and the utmost elimination of the negative effect of the native language transfer would bring about a great advance in English quality improvement of the learners.The learners should be taught not to avoid negative influence.展开更多
A heavy-ion irradiation experiment is studied in digital storage cells with different design approaches in 130？nm CMOS bulk Si and silicon-on-insulator （SOI） technologies. The effectiveness of linear energy transf...A heavy-ion irradiation experiment is studied in digital storage cells with different design approaches in 130？nm CMOS bulk Si and silicon-on-insulator （SOI） technologies. The effectiveness of linear energy transfer （LET） with a tilted ion beam at the 130？nm technology node is obtained. Tests of tilted angles θ=0 ° , 30 ° and 60 ° with respect to the normal direction are performed under heavy-ion Kr with certain power whose LET is about 40？MeVcm 2 /mg at normal incidence. Error numbers in D flip-flop chains are used to determine their upset sensitivity at different incidence angles. It is indicated that the effective LETs for SOI and bulk Si are not exactly in inverse proportion to cosθ , furthermore the effective LET for SOI is more closely in inverse proportion to cosθ compared to bulk Si, which are also the well known behavior. It is interesting that, if we design the sample in the dual interlocked storage cell approach, the effective LET in bulk Si will look like inversely proportional to cosθ very well, which is also specifically explained.展开更多
The present investigation addresses the simultaneous effects of heat and mass transfer in the mixed convection peristaltic flow of viscous fluid in an asymmetric channel. The channel walls exhibit the convective bound...The present investigation addresses the simultaneous effects of heat and mass transfer in the mixed convection peristaltic flow of viscous fluid in an asymmetric channel. The channel walls exhibit the convective boundary conditions. In addition, the effects due to Soret and Dufour are taken into consideration. Resulting problems are solved for the series solutions. Numerical values of heat and mass transfer rates are displayed and studied. Results indicate that the concentration and temperature of the fluid increase whereas the mass transfer rate at the wall decreases with increase of the mass transfer Biot number. Furthermore, it is observed that the temperature decreases with the increase of the heat transfer Biot number.展开更多
Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- ...Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- bis（phenyl）-10-（pentafluorophenyl）corrole Mn（V）-oxo（F_5CMn（V）-oxo） and 5,10,15-tris（phenyl）corrole Mn（V）-oxo（F_0CMn（V）-oxo） with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn（V）-oxo corrole and alkene is solvent-dependent.展开更多
Experimental study of the local and average heat transfer characteristics of a single round jet impinging on the concave surfaces was conducted in this work to gain in-depth knowledge of the curvature effects.The expe...Experimental study of the local and average heat transfer characteristics of a single round jet impinging on the concave surfaces was conducted in this work to gain in-depth knowledge of the curvature effects.The experiments were conducted by employing a piccolo tube with one single jet hole over a wide range of parameters：jet Reynolds number from 27000 to 130000,relative nozzle to surface distance from 3.3 to 30,and relative surface curvature from 0.005 to 0.030.Experimental results indicate that the surface curvature has opposite effects on heat transfer characteristics.On one hand,an increase of relative nozzle to surface distance（increasing jet diameter in fact）enhances the average heat transfer around the surface for the same curved surface.On the other hand,the average Nusselt number decreases as relative nozzle to surface distance increases for a fixed jet diameter.Finally,experimental data-based correlations of the average Nusselt number over the curved surface were obtained with consideration of surface curvature effect.This work contributes to a better understanding of the curvature effects on heat transfer of a round jet impingement on concave surfaces,which is of high importance to the design of the aircraft anti-icing system.展开更多
We demonstrate a triple-pass scheme for coherent transfer of optical frequency and the delay effect on the fiber phase noise compensation. It is theoretically proved that the delay effect consists of both fiber delay ...We demonstrate a triple-pass scheme for coherent transfer of optical frequency and the delay effect on the fiber phase noise compensation. It is theoretically proved that the delay effect consists of both fiber delay and servo delay. The delay effect confines the servo bandwidth within 1/8 and induces a residual fiber phase noise after noise compensation. For a 25-km-long fiber, the servo bandwidth is found to be around 1 k Hz, and the fiber phase noise is suppressed approaching to the theoretical limitation. The triple-pass scheme enables the simultaneous transfer of optical frequency to multiple remote users. The performance of noise compensator in the triple-pass scheme can achieve a similar level result compared with that in the double-pass scheme.展开更多
Magnetic radiation phenomena appear inevitably in the magnetic-resonance wireless power transfer （MR-WPT） system, and regarding this problem the magnetic-shielding scheme is applied to improve the electromagnetic pe...Magnetic radiation phenomena appear inevitably in the magnetic-resonance wireless power transfer （MR-WPT） system, and regarding this problem the magnetic-shielding scheme is applied to improve the electromagnetic performance in engineering. In this study, the shielding effectiveness of a two-coil MR-WPT system for different material shields is analyzed in theory using Moser＇s formula and Schelkunoff＇s formula. On this basis a candidate magnetic-shielding scheme with a double-layer structure is determined, which has better shielding effectiveness and coils coupling coefficient. Finally, some finite element simulation results validate the correctness of the theoretical analysis, and the shielding effectiveness with the double-layer shield in maximum is 30？dB larger than the one with the single-layer case.展开更多
The effects of mass transfer and physical properties upon the thinning and rupture of adraining plane parallel film are investigated.An equation is derived in which the thinning rate is afunction of bulk properties.su...The effects of mass transfer and physical properties upon the thinning and rupture of adraining plane parallel film are investigated.An equation is derived in which the thinning rate is afunction of bulk properties.surface properties(surface tension,surface viscosities,and the variationof surface tension with surface concentration),intermolecular forces(London-van der Waals forcesand electrostatic double layer forces),adsorption and surface diffusion coefficients,bubble size andfilm thickness.An estimation for the critical thickness at which a film rupture is carried out and thecoalescence time is obtained by integration to the critical thickness,The coalescence time is predictedas a function of bulk and surface properties,London-van der forces,adsorption and surfacediffusion coefficients,and bubble size.展开更多
This article deals with the effects of a blowing ratio measured with narrowband liquid crystal in transonic experiments on the heat transfer characteristics of trailing edge cutback. The experimental results are compa...This article deals with the effects of a blowing ratio measured with narrowband liquid crystal in transonic experiments on the heat transfer characteristics of trailing edge cutback. The experimental results are compared and contrasted in terms of available data for traditional experiments with thermocouples. It is concluded that the blowing ratio exerts rather significant effects on film cooling effectiveness distribution of the rib center line. As the blowing ratio decreases, similar to the cooling effectiveness distribution curve of the slot center line, that of the rib center line makes a clockwise rotation about the end. When the blowing ratio increases, the regular film cooling effectiveness curve of the surface becomes rather smooth. On the whole measuring surface, the most intensive heat transfer occurs at the extended borderline of the slot and the rib, neither at the rib center line nor at the slot center line. The experimental results of cooling effectiveness measured with thermocouples are lower than those with liquid crystal. In addition, the transient experiments using narrowband liquid crystal can eliminate the higher errors of Nusselt numbers in measurements with thermocouples at the slot outlet.展开更多
Semi-empirical molecular orbital theory AMI method is employed to study the ortho-position substituent impact on intramolecular proton transfer reaction of perylenequinone. The calculation demonstrates that the peryle...Semi-empirical molecular orbital theory AMI method is employed to study the ortho-position substituent impact on intramolecular proton transfer reaction of perylenequinone. The calculation demonstrates that the perylenequinone molecule is of stable structure. and all substituents may cause the decrease of barriers for the hydrogen transfer reaction.展开更多
In this article, a numerical model combining conduction and radiation is developed based on two flux approximation to predict the heat transfer behavior of fibrous insulation used in thermal protection systems. Monte ...In this article, a numerical model combining conduction and radiation is developed based on two flux approximation to predict the heat transfer behavior of fibrous insulation used in thermal protection systems. Monte Carlo method is utilized to determine the modified radiative properties with experimentally measured transient external temperature as high as 1 000 K. It is found that the estimated radiative properties become time-independent after about t = 3 000 s. By comparing the predicted to the measured results in transient state, the contact resistance exerts significant influences upon the temperature distribution in the specimen. Results show that the averaged absolute deviation is 3.25% when contact resistance is neglected in heat transfer model, while 1.82% with no contact resistance.展开更多
Three-dimensional numerical computations are conducted to investigate the effects of the blowing ratio and corrugation geometry on the adiabatic film cooling effectiveness as well as the heat transfer coefficient over...Three-dimensional numerical computations are conducted to investigate the effects of the blowing ratio and corrugation geometry on the adiabatic film cooling effectiveness as well as the heat transfer coefficient over a transverse corrugated surface.It is noticeable that the adiabatic wall temperature on the wavy valley of the transverse corrugated surface is relatively lower than that on the wavy peak.Surface corrugation has a relatively obvious influence on the laterallyaveraged adiabatic film cooling effectiveness in the region where the effusion film layer is developed,but has little influence in the front region.Compared to a flat surface,the transverse corrugated surface produces a smaller adiabatic film cooling effectiveness and a higher heat transfer coefficient ratio.The effusion cooling difference between the flat and corrugated surfaces behaves more obviously under a small aspect ratio of the wavy corrugation.展开更多
Alloimmunization was combined with lympho-kine activated killer (LAK) cells to assess its effect on mammary carcinoma in rats. The animals were injected with both irradiated allosplenocytes and syngeneic LAK cells. Me...Alloimmunization was combined with lympho-kine activated killer (LAK) cells to assess its effect on mammary carcinoma in rats. The animals were injected with both irradiated allosplenocytes and syngeneic LAK cells. Metastatic lung nodules were markedly reduced using combined therapy when compared with the transfer of LAK cells or alloimmuni-zation alone. IL-2 activity in the serum of alloim-munized rats could be detected. This activity, maintained in vivo for one week, may be responsible for enhancing the antitumor effect of transferred LAK cells.展开更多
An analysis is performed to study thermo-diffusion and diffusion-thermo effects on mixed convection heat and mass transfer boundary layer flow along an inclined (solar collector) plate. The resulting governing equatio...An analysis is performed to study thermo-diffusion and diffusion-thermo effects on mixed convection heat and mass transfer boundary layer flow along an inclined (solar collector) plate. The resulting governing equations are transformed and then solved numerically using the local nonsimilarity method and Runge-Kutta shooting quadrature. A parametric study illustrating the influence of thermal buoyancy parameter (ζ), Prandtl number (Pr), Schmidt number (Sc), Soret number (Sr), Dufour number (Du) and concentration-to- thermal-buoyancy ratio parameter, N, on the fluid velocity, temperature and concentration profiles as well as on local skin-friction, Nusselt and Sherwood numbers is conducted. For positive inclination angle of the plate (γ = 70 degrees), flow velocity (f') is strongly increased i.e. accelerated, with thermal buoyancy force parameter (ζ), in particular closer to the plate surface;further into the boundary layer, ζ has a much reduced effect. Conversely temperature (θ) and concentration (ψ) is decreased with increasing thermal buoyancy parameter, ζ. For negative plate inclination, the flow is accelerated whereas for positive inclination it is decelerated i.e. velocity is reduced. Conversely with negative plate inclination both the temperature and concentration in the boundary layer is reduced with the opposite apparent for positive inclination. Increasing Prandtl number strongly reduces temperature in the regime whereas an increase in Schmidt number boosts temperatures with temperature overshoots near the plate surface for Sc = 3 and 5 (i.e. for Sc > 1). Concentration is reduced continuously throughout the boundary layer, however, with increasing Schmidt number. A positive increase in concentration-to-thermal-buoyancy ratio parameter, N, significantly accelerates the flow in the domain, whereas negative N causes a deceleration. A velocity overshoot is also identified for N = 20, at intermediate distance from the plate surface. Negative N (thermal and concentration buoyancy forces oppose each other) induces a slight increase in both fluid temperature and concentration, with the reverse observed for positive N (thermal and concentration buoyancy forces assisting each other). Increasing Dufour number respectively causes a rise in temperature and a decrease in concentration, whereas an increase in Soret number cools the fluid i.e. reduces temperature and enhances concentration values. In the absence of Soret and Dufour effects, positive N causes a monotonic increase in local Nusselt number, NuxRex-1/2 with ζ Cos γ, for N = -1 the local Nusselt number remains constant for all values of parameter, ζ Cos γ. Local Sherwood number, ShxRex-1/2 is boosted considerably with higher Schmidt numbers and also with positive N values. The computations in the absence of Soret and Dufour effects correlate accurately with the earlier study by Chen et al. (1980).展开更多
Taking Shuangliu County,Chengdu City,China as an example,evaluation index system for the rights protection effects of farmland transfer is established contract from three aspects of basic information,transfer agreemen...Taking Shuangliu County,Chengdu City,China as an example,evaluation index system for the rights protection effects of farmland transfer is established contract from three aspects of basic information,transfer agreement and legal safeguards in the contracts.According to the investigation data,weight of evaluation index is determined by both entropy weight and Analytic Hierarchy Process.Comprehensive index method is used to evaluate the rights protection effects of farmland transfer contract in the flat dam,high hill and low hill in Shuangliu County,Chengdu,China.Result shows that the transfer agreement of farmland and the basic information of contract greatly affect the rights protection effects of farmland transfer contract.There are differences in the five indices of the information of the signature of contract,pricing for payment,time limit for farmland transfer,transfer mode of farmland,and use range of farmland transfer.During the farmland transfer in reality,there are three hidden dangers in farmer's land rights and interests,which are the ill-formed transfer behavior,the relatively low income of farmers from farmland transfer,and the quality decline of farmland and difficult full reclamation in transfer period.Based on the evaluation result and investigation data,countermeasures are put forward to improve the rights protection effects of farmland transfer contract.展开更多
Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O soluti...Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.展开更多
基金Funding for this study was provided by Stiftung für Komplementrmedizin, Gottfried und Julia Bangerter-Rhyner Stiftung and Parrotia Stiftung
文摘in recent years research investigating various health benefits of Taiji practice has markedly increased. Despite this growing scientific interest, essential questions such as to what extent a Taiji course may exert noticeable effects in participants＇ everyday life, what these effects are, and how and where potential transfer effects occur, have hardly been considered. The aim of our study was to explore transfer effects from a Taiji course into participants＇ daily lives. METHODS： We conducted a longitudinal observational study in 45 healthy participants at the end of their three-month Taiji beginner course （tpl） and at two months （tp2） as well as one year after course completion （tp3）. Participants were asked to report their Taiji practice behavior at all time points, as well as to rate and describe perceived transfer effects of Taiji course contents on their daily life at tpl and tp3. RESULTS： Transfer effects were reported by 91.1% of all respondents after course completion （tpl） and persisted in 73.3% at the one-year follow-up assessment （tp3）, counting ＂increase of self-efficacy＂, ＂improvement of stress management＂, and ＂increase of body awareness＂ as the most frequently mentioned effects. Transfer effects predominantly occurred in participants＇ work and social environments, as well as during everyday activities in public areas. While self- reliant Taiji practice frequency significantly decreased from 82.2% at tpl to 55.6% at tp3 （P 〈 0.001）, the magnitude of self-reported transfer effects did not （P = 0.35）. As explorative analyses revealed, regular Taiji course attendance was highly correlated with stronger transfer effects at tpl （r = 0.51; P 〈 0.001） and tp3 （r = 0.35; P = 0.020）. Participants reporting high self-reliant Taiji practice frequency at tp2 were likely to maintain a regular practice routine at tp3 （r = 0.42; P 〈 0.004）, whereas self-reliant practice frequency and transfer effects at tpl were positively correlated with self-reliant practice frequency at tp3 on a trend level （r 〈 0.27; P 〉 0.08）. CONCLUSION： Our data underline the importance of regular course participation for pronounced and long lasting transfer effects into participants＇ everyday life. We discuss that several context and process-related aspects of a Taiji intervention are potentially relevant factors for enhancement of transfer effect.
基金supported by the National Natural Science Foundation of China(Grant No.U21A2054,51961011,52273285,52262032)National Key Research and Development Program of China(Grant No.2022YFE0119100)Sinoma Institute of Materials Research(Guang Zhou)Co.,Ltd(SIMR)for assisting the characterization of TEM images/SAED patterns.
文摘SiGe based alloy is a promising medium-high temperature thermoelectric material that has been applied in the field of aerospace exploration.So far,utilizing the second phase to promote the scattering of phonons is a common way to improve the thermoelectric performance of SiGe based alloy,but this often deteriorates the electrical properties.In this study,the Si_(80)Ge_(20)P_(1)/CoSi_(2) composites have been prepared by mechanical alloying and spark plasma sintering,and the content of cobalt silicide(CoSi_(2))nanoparticles have been manipulated.Since the CoSi_(2) nanoparticles possess higher carrier concentration and smaller work function than the Si_(80)Ge_(20)P_(1) matrix,the carrier concentrations of composites have been pushed up due the charge transfer effect.Meanwhile,the formation of nano-sized phase interfaces and stacking faults in the composites has enhanced the scattering of low-frequency phonons.As a result,the optimal power factor of 3.41 mW·m^(-1),K^(-2) and thermal conductivity of 2.29 W·m^(-1),K^(-1) have been achieved,and the corresponding zT reaches up to 1.3 in the Si_(80)Ge_(20)P_(1)+0.5%CoSi_(2)(in mole)composite at 873 K.This work provides a new idea for developing the performance of SiGe based alloy.
文摘A heat transfer model for three-fluid separated heat pipe exchanger was analyzed,and the temperature transfer matrix for general three-fluid separated heat exchanger working in parallel-flow or counter-flow mode was obtained.It was found that the forms of temperature transfer matrix are similar for heat pipe rows with equal or different heat transfer surface area.Furthermore,by using the temperature transfer matrix of the heat pipe exchanger,the relationship between heat transfer effectiveness θ 1,θ 2 and M,NTU,U,Δt i were derived for the exchanger operating in parallel-flow or counter-flow mode,and a simple special example was adopted to demonstrate the correctness of these relationships.
文摘As the native language transfer inevitably exerts definite influences on English study,the paper is to give a more detailed analysis to the positive and negative effects in one's L2 learning.In English teaching,the full use of the positive effect of the native language transfer and the utmost elimination of the negative effect of the native language transfer would bring about a great advance in English quality improvement of the learners.The learners should be taught not to avoid negative influence.
基金Supported by the Key Laboratory of Microsatellites,Chinese Academy of Sciences
文摘A heavy-ion irradiation experiment is studied in digital storage cells with different design approaches in 130？nm CMOS bulk Si and silicon-on-insulator （SOI） technologies. The effectiveness of linear energy transfer （LET） with a tilted ion beam at the 130？nm technology node is obtained. Tests of tilted angles θ=0 ° , 30 ° and 60 ° with respect to the normal direction are performed under heavy-ion Kr with certain power whose LET is about 40？MeVcm 2 /mg at normal incidence. Error numbers in D flip-flop chains are used to determine their upset sensitivity at different incidence angles. It is indicated that the effective LETs for SOI and bulk Si are not exactly in inverse proportion to cosθ , furthermore the effective LET for SOI is more closely in inverse proportion to cosθ compared to bulk Si, which are also the well known behavior. It is interesting that, if we design the sample in the dual interlocked storage cell approach, the effective LET in bulk Si will look like inversely proportional to cosθ very well, which is also specifically explained.
基金the Higher Education Commission of Pakistan (HEC) for the financial support through Indigenous program
文摘The present investigation addresses the simultaneous effects of heat and mass transfer in the mixed convection peristaltic flow of viscous fluid in an asymmetric channel. The channel walls exhibit the convective boundary conditions. In addition, the effects due to Soret and Dufour are taken into consideration. Resulting problems are solved for the series solutions. Numerical values of heat and mass transfer rates are displayed and studied. Results indicate that the concentration and temperature of the fluid increase whereas the mass transfer rate at the wall decreases with increase of the mass transfer Biot number. Furthermore, it is observed that the temperature decreases with the increase of the heat transfer Biot number.
基金The financial support from the National Natural Science Foundation of China(Nos.20971046 and 21171057)
文摘Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- bis（phenyl）-10-（pentafluorophenyl）corrole Mn（V）-oxo（F_5CMn（V）-oxo） and 5,10,15-tris（phenyl）corrole Mn（V）-oxo（F_0CMn（V）-oxo） with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn（V）-oxo corrole and alkene is solvent-dependent.
基金supported by the National Natural Science Foundation of China(No.51206008)the EU Marie Curie Actions-International Incoming Fellowships(No.FP7PEOPLE-2013-IIF-626576)
文摘Experimental study of the local and average heat transfer characteristics of a single round jet impinging on the concave surfaces was conducted in this work to gain in-depth knowledge of the curvature effects.The experiments were conducted by employing a piccolo tube with one single jet hole over a wide range of parameters：jet Reynolds number from 27000 to 130000,relative nozzle to surface distance from 3.3 to 30,and relative surface curvature from 0.005 to 0.030.Experimental results indicate that the surface curvature has opposite effects on heat transfer characteristics.On one hand,an increase of relative nozzle to surface distance（increasing jet diameter in fact）enhances the average heat transfer around the surface for the same curved surface.On the other hand,the average Nusselt number decreases as relative nozzle to surface distance increases for a fixed jet diameter.Finally,experimental data-based correlations of the average Nusselt number over the curved surface were obtained with consideration of surface curvature effect.This work contributes to a better understanding of the curvature effects on heat transfer of a round jet impingement on concave surfaces,which is of high importance to the design of the aircraft anti-icing system.
基金Supported by the National Natural Science Foundation of China under Grant No 61378037the Fundamental Research Funds for the Central Universities under Grant No JUSRP51628B
文摘We demonstrate a triple-pass scheme for coherent transfer of optical frequency and the delay effect on the fiber phase noise compensation. It is theoretically proved that the delay effect consists of both fiber delay and servo delay. The delay effect confines the servo bandwidth within 1/8 and induces a residual fiber phase noise after noise compensation. For a 25-km-long fiber, the servo bandwidth is found to be around 1 k Hz, and the fiber phase noise is suppressed approaching to the theoretical limitation. The triple-pass scheme enables the simultaneous transfer of optical frequency to multiple remote users. The performance of noise compensator in the triple-pass scheme can achieve a similar level result compared with that in the double-pass scheme.
基金Supported by the National Natural Science Foundation of China under Grant No 51377185
文摘Magnetic radiation phenomena appear inevitably in the magnetic-resonance wireless power transfer （MR-WPT） system, and regarding this problem the magnetic-shielding scheme is applied to improve the electromagnetic performance in engineering. In this study, the shielding effectiveness of a two-coil MR-WPT system for different material shields is analyzed in theory using Moser＇s formula and Schelkunoff＇s formula. On this basis a candidate magnetic-shielding scheme with a double-layer structure is determined, which has better shielding effectiveness and coils coupling coefficient. Finally, some finite element simulation results validate the correctness of the theoretical analysis, and the shielding effectiveness with the double-layer shield in maximum is 30？dB larger than the one with the single-layer case.
基金Partially supported by National Natural Science Foundation of China
文摘The effects of mass transfer and physical properties upon the thinning and rupture of adraining plane parallel film are investigated.An equation is derived in which the thinning rate is afunction of bulk properties.surface properties(surface tension,surface viscosities,and the variationof surface tension with surface concentration),intermolecular forces(London-van der Waals forcesand electrostatic double layer forces),adsorption and surface diffusion coefficients,bubble size andfilm thickness.An estimation for the critical thickness at which a film rupture is carried out and thecoalescence time is obtained by integration to the critical thickness,The coalescence time is predictedas a function of bulk and surface properties,London-van der forces,adsorption and surfacediffusion coefficients,and bubble size.
文摘This article deals with the effects of a blowing ratio measured with narrowband liquid crystal in transonic experiments on the heat transfer characteristics of trailing edge cutback. The experimental results are compared and contrasted in terms of available data for traditional experiments with thermocouples. It is concluded that the blowing ratio exerts rather significant effects on film cooling effectiveness distribution of the rib center line. As the blowing ratio decreases, similar to the cooling effectiveness distribution curve of the slot center line, that of the rib center line makes a clockwise rotation about the end. When the blowing ratio increases, the regular film cooling effectiveness curve of the surface becomes rather smooth. On the whole measuring surface, the most intensive heat transfer occurs at the extended borderline of the slot and the rib, neither at the rib center line nor at the slot center line. The experimental results of cooling effectiveness measured with thermocouples are lower than those with liquid crystal. In addition, the transient experiments using narrowband liquid crystal can eliminate the higher errors of Nusselt numbers in measurements with thermocouples at the slot outlet.
文摘Semi-empirical molecular orbital theory AMI method is employed to study the ortho-position substituent impact on intramolecular proton transfer reaction of perylenequinone. The calculation demonstrates that the perylenequinone molecule is of stable structure. and all substituents may cause the decrease of barriers for the hydrogen transfer reaction.
基金National High-tech Research and Development Program(2006AA705317)
文摘In this article, a numerical model combining conduction and radiation is developed based on two flux approximation to predict the heat transfer behavior of fibrous insulation used in thermal protection systems. Monte Carlo method is utilized to determine the modified radiative properties with experimentally measured transient external temperature as high as 1 000 K. It is found that the estimated radiative properties become time-independent after about t = 3 000 s. By comparing the predicted to the measured results in transient state, the contact resistance exerts significant influences upon the temperature distribution in the specimen. Results show that the averaged absolute deviation is 3.25% when contact resistance is neglected in heat transfer model, while 1.82% with no contact resistance.
文摘Three-dimensional numerical computations are conducted to investigate the effects of the blowing ratio and corrugation geometry on the adiabatic film cooling effectiveness as well as the heat transfer coefficient over a transverse corrugated surface.It is noticeable that the adiabatic wall temperature on the wavy valley of the transverse corrugated surface is relatively lower than that on the wavy peak.Surface corrugation has a relatively obvious influence on the laterallyaveraged adiabatic film cooling effectiveness in the region where the effusion film layer is developed,but has little influence in the front region.Compared to a flat surface,the transverse corrugated surface produces a smaller adiabatic film cooling effectiveness and a higher heat transfer coefficient ratio.The effusion cooling difference between the flat and corrugated surfaces behaves more obviously under a small aspect ratio of the wavy corrugation.
文摘Alloimmunization was combined with lympho-kine activated killer (LAK) cells to assess its effect on mammary carcinoma in rats. The animals were injected with both irradiated allosplenocytes and syngeneic LAK cells. Metastatic lung nodules were markedly reduced using combined therapy when compared with the transfer of LAK cells or alloimmuni-zation alone. IL-2 activity in the serum of alloim-munized rats could be detected. This activity, maintained in vivo for one week, may be responsible for enhancing the antitumor effect of transferred LAK cells.
文摘An analysis is performed to study thermo-diffusion and diffusion-thermo effects on mixed convection heat and mass transfer boundary layer flow along an inclined (solar collector) plate. The resulting governing equations are transformed and then solved numerically using the local nonsimilarity method and Runge-Kutta shooting quadrature. A parametric study illustrating the influence of thermal buoyancy parameter (ζ), Prandtl number (Pr), Schmidt number (Sc), Soret number (Sr), Dufour number (Du) and concentration-to- thermal-buoyancy ratio parameter, N, on the fluid velocity, temperature and concentration profiles as well as on local skin-friction, Nusselt and Sherwood numbers is conducted. For positive inclination angle of the plate (γ = 70 degrees), flow velocity (f') is strongly increased i.e. accelerated, with thermal buoyancy force parameter (ζ), in particular closer to the plate surface;further into the boundary layer, ζ has a much reduced effect. Conversely temperature (θ) and concentration (ψ) is decreased with increasing thermal buoyancy parameter, ζ. For negative plate inclination, the flow is accelerated whereas for positive inclination it is decelerated i.e. velocity is reduced. Conversely with negative plate inclination both the temperature and concentration in the boundary layer is reduced with the opposite apparent for positive inclination. Increasing Prandtl number strongly reduces temperature in the regime whereas an increase in Schmidt number boosts temperatures with temperature overshoots near the plate surface for Sc = 3 and 5 (i.e. for Sc > 1). Concentration is reduced continuously throughout the boundary layer, however, with increasing Schmidt number. A positive increase in concentration-to-thermal-buoyancy ratio parameter, N, significantly accelerates the flow in the domain, whereas negative N causes a deceleration. A velocity overshoot is also identified for N = 20, at intermediate distance from the plate surface. Negative N (thermal and concentration buoyancy forces oppose each other) induces a slight increase in both fluid temperature and concentration, with the reverse observed for positive N (thermal and concentration buoyancy forces assisting each other). Increasing Dufour number respectively causes a rise in temperature and a decrease in concentration, whereas an increase in Soret number cools the fluid i.e. reduces temperature and enhances concentration values. In the absence of Soret and Dufour effects, positive N causes a monotonic increase in local Nusselt number, NuxRex-1/2 with ζ Cos γ, for N = -1 the local Nusselt number remains constant for all values of parameter, ζ Cos γ. Local Sherwood number, ShxRex-1/2 is boosted considerably with higher Schmidt numbers and also with positive N values. The computations in the absence of Soret and Dufour effects correlate accurately with the earlier study by Chen et al. (1980).
文摘Taking Shuangliu County,Chengdu City,China as an example,evaluation index system for the rights protection effects of farmland transfer is established contract from three aspects of basic information,transfer agreement and legal safeguards in the contracts.According to the investigation data,weight of evaluation index is determined by both entropy weight and Analytic Hierarchy Process.Comprehensive index method is used to evaluate the rights protection effects of farmland transfer contract in the flat dam,high hill and low hill in Shuangliu County,Chengdu,China.Result shows that the transfer agreement of farmland and the basic information of contract greatly affect the rights protection effects of farmland transfer contract.There are differences in the five indices of the information of the signature of contract,pricing for payment,time limit for farmland transfer,transfer mode of farmland,and use range of farmland transfer.During the farmland transfer in reality,there are three hidden dangers in farmer's land rights and interests,which are the ill-formed transfer behavior,the relatively low income of farmers from farmland transfer,and the quality decline of farmland and difficult full reclamation in transfer period.Based on the evaluation result and investigation data,countermeasures are put forward to improve the rights protection effects of farmland transfer contract.
文摘Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly.
