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Investigating short- and long-term transfer effects of a Taiji beginner course in participants' daily life
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作者 Agnes Maria Schitter Brigitte Ausfeld-Hafter Marko Nedeljkovic 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第5期295-304,共10页
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
关键词 Tai Ji daily life transfer effects SELF-EFFICACY longitudinal study healthy subjects Tai Ji daily life transfer effects SELF-EFFICACY longitudinal study healthy subjects
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Heat Transfer Effectiveness of Three-Fluid Separated Heat Pipe Exchanger 被引量:3
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作者 Chengming Shi Yang Wang Ying Yang Quan Liao 《Journal of Thermal Science》 SCIE EI CAS CSCD 2011年第1期64-69,共6页
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
关键词 heat pipes three-fluid heat exchangers heat transfer effectiveness temperature transfer matrix
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A Brief Analysis of the Positive and Negative Effectsof the Native Language Transfer in English Study 被引量:2
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作者 徐玲 丁琳 《科技信息》 2010年第35期I0276-I0276,I0285,共2页
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
关键词 英语学习 英语翻译 阅读 母语迁移
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Influence of Tilted Angle on Effective Linear Energy Transfer in Single Event Effect Tests for Integrated Circuits at 130 nm Technology Node 被引量:2
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作者 张乐情 卢健 +5 位作者 胥佳灵 刘小年 戴丽华 徐依然 毕大炜 张正选 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第11期119-122,共4页
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
关键词 SOI Influence of Tilted Angle on effective Linear Energy transfer in Single Event effect Tests for Integrated Circuits at 130 nm Tec
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Mixed convective heat and mass transfer analysis for peristaltic transport in an asymmetric channel with Soret and Dufour effects 被引量:5
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作者 F.M.Abbasi A.Alsaedi T.Hayat 《Journal of Central South University》 SCIE EI CAS 2014年第12期4585-4591,共7页
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
关键词 peristaltic transport heat and mass transfer Soret and Dufour effects convective boundary conditions
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Delay Effect on Coherent Transfer of Optical Frequency Based on a Triple-Pass Scheme 被引量:1
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作者 Chao-qun Ma Li-Fei Wu +2 位作者 Jiao Gu Yan-He Chen Guo-Qing Chen 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第8期9-13,共5页
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
关键词 Delay effect on Coherent transfer of Optical Frequency Based on a Triple-Pass Scheme AOM
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Numerical Analysis of Magnetic-Shielding Effectiveness for Magnetic Resonant Wireless Power Transfer System 被引量:1
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作者 卢伟国 李惠荣 +1 位作者 陈伟铭 刘黎辉 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第8期148-151,共4页
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
关键词 MR WPT Numerical Analysis of Magnetic-Shielding effectiveness for Magnetic Resonant Wireless Power transfer System
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EFFECTS OF MASS TRANSFER ON THE THINNING AND RUPTURE OF A PLANE PARALLEL LIQUID FILM
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作者 李佟茗 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1994年第3期33-49,共17页
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
关键词 BUBBLE COALESCENCE thin film drainage mass transfer effect on COALESCENCE
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Theoretical Study of Impact of Side Substituent Effecton Intramolecular Proton Transfer of Perylenequinone
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作者 Ying QIAN Yan WANG Ruo Zhuang LIU(Department of Chemical and Environmental Engineering, Beijing Polytechnic University, Beliing100022)(Department of Chemistry, Beijing Normal University, Beijing 100875) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第4期317-320,共4页
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
关键词 perylenequinone AM1 method proton transfer substituent effect
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THE EFFECT OF THE TRANSFER OF LAK CELLS, COMBINED WITH ALLOIMMUNIZATION, ON THE PULMONARY METASTASES OF RAT MAMMARY CARCINOMA
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作者 李松枝 巴德年 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第1期16-19,共4页
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
关键词 LAK THE effect OF THE transfer OF LAK CELLS COMBINED WITH ALLOIMMUNIZATION ON THE PULMONARY METASTASES OF RAT MAMMARY CARCINOMA
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Numerical Modelling of Non-similar Mixed Convection Heat and Species Transfer along an Inclined Solar Energy Collector Surface with Cross Diffusion Effects 被引量:1
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作者 Osman Anwar Bég Ahmed Bakier +1 位作者 Ramachandra Prasad Swapan Kumar Ghosh 《World Journal of Mechanics》 2011年第4期185-196,共12页
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 (&#950), 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 (&#947 = 70 degrees), flow velocity (f') is strongly increased i.e. accelerated, with thermal buoyancy force parameter (&#950), in particular closer to the plate surface;further into the boundary layer, &#950 has a much reduced effect. Conversely temperature (&#952) and concentration (&#968) is decreased with increasing thermal buoyancy parameter, &#950. 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 &#950 Cos &#947, for N = -1 the local Nusselt number remains constant for all values of parameter, &#950 Cos &#947. 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
关键词 HEAT and Mass transfer Inclined Plate Soret/Dufour effectS BUOYANCY Numerical Solar Energy
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Analysis of Hidden Danger in Farmer's Rights and Interests during Farmland Transfer——An Evaluation of Rights Safeguarding Effect of Farmland Transfer Contract 被引量:2
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作者 WANG Shu-han WU Xiu-min 《Asian Agricultural Research》 2010年第8期61-64,共4页
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
关键词 Farmland transfer Farmer's rights and interests Rights safeguarding effect AHP China
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Hall Effect on Peristaltic Flow of Third Order Fluid in a Porous Medium with Heat and Mass Transfer
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作者 Nabil T. M. Eldabe Ahmed Y. Ghaly +2 位作者 Sallam N. Sallam Khaled Elagamy Yasmeen M. Younis 《Journal of Applied Mathematics and Physics》 2015年第9期1138-1150,共13页
We investigated the influence of hall, heat and mass transfer on the peristaltic flow of MHD third order fluid under long-wavelength and low Reynolds number approximation. The governing equations are solved analytical... We investigated the influence of hall, heat and mass transfer on the peristaltic flow of MHD third order fluid under long-wavelength and low Reynolds number approximation. The governing equations are solved analytically with the appropriate boundary conditions by using perturbation technique. The formula of velocity with temperature and concentration is obtained analytically as a function of the physical parameters of the problem. 展开更多
关键词 Peristaltic Flow THIRD Order FLUID HALL effect Heat Mass transfer
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发热包传热效果及其对冻干鱼肉复水品质的影响
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作者 郝淑贤 韦丽娜 +6 位作者 魏涯 黄卉 相欢 赵永强 岑剑伟 王迪 李来好 《广东海洋大学学报》 CAS CSCD 北大核心 2024年第4期139-146,共8页
【目的】探究发热包传热影响因素及其对冻干鱼肉复水品质的影响,为罗非鱼自热产品开发与推广提供参考。【方法】研究热源质量(70、80、90和120 g)、激活剂用量(发热包质量的2.0倍、2.5倍、3.0倍和3.5倍)、内胆材质[聚丙烯(PP)和铝]和环... 【目的】探究发热包传热影响因素及其对冻干鱼肉复水品质的影响,为罗非鱼自热产品开发与推广提供参考。【方法】研究热源质量(70、80、90和120 g)、激活剂用量(发热包质量的2.0倍、2.5倍、3.0倍和3.5倍)、内胆材质[聚丙烯(PP)和铝]和环境温度(6、17和25℃)对发热包传热效果的影响,分析自热过程鱼肉复水品质的变化。【结果】随热源质量增加,传热效果显著提高(P <0.05),持续保温效果增强;激活剂用量为发热包质量的3.0~3.5倍时,传热效果较好。热源放热量、吸热量与热源质量、环境温度呈正相关。发热包质量为90 g,激活剂用量为发热包质量的3.0倍时,25℃条件下反应初期水合反应剧烈,反应使发热包体积胀大2倍以上,释放大量热能,促进干制鱼肉快速复热复水。内胆材质对产品传热影响差异不显著(P> 0.05)。10~15 min鱼块内部基本复水,鱼肉中心温度达到90℃以上,复水后鱼肉硬度约为70 g,弹性和咀嚼性影响不显著。【结论】热源质量高于90 g,激活剂用量3.0~3.5倍,铝和PP材质,6℃以上的环境温度均可满足发热要求,此条件下,10~15 min复热时间冻干鱼肉品质较好,符合自热产品速食需求。 展开更多
关键词 发热包 传热效果 冻干鱼肉 质构
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Fading Effects on the Performance of OFDM-Based Systems Using Channel Transfer Function
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作者 Chie Dou 《通讯和计算机(中英文版)》 2012年第12期1404-1411,共8页
关键词 OFDM系统 信道增益 性能比较 衰落信道 传递函数 无线局域网 概率分布 信号噪声比
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微尺度下润湿性表面对双气泡传热特性的影响
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作者 战洪仁 纪柏辰 +3 位作者 刘东灵 刘德彬 张先珍 李帅 《化学工程》 CAS CSCD 北大核心 2024年第5期13-18,38,共7页
为探究混合润湿表面双气泡生长过程的特点和传热特性,利用格子Boltzmann方法研究混合润湿性表面不同因素对生长和传热过程的影响规律。结果表明:对于纯润湿性表面,随着润湿性的降低,气泡成核时间减少,气泡脱离表面时间呈增加趋势,双气... 为探究混合润湿表面双气泡生长过程的特点和传热特性,利用格子Boltzmann方法研究混合润湿性表面不同因素对生长和传热过程的影响规律。结果表明:对于纯润湿性表面,随着润湿性的降低,气泡成核时间减少,气泡脱离表面时间呈增加趋势,双气泡生长过程的平均热流密度呈减少趋势。混合表面可以实现相比纯润湿性表面更高的脱离频率和更好的换热效果,混合润湿表面整体脱离频率在(L_(q)/△x)>0.37(△x<30)时呈增加趋势,在(L_(q)/△x)≤0.37(△x≥30)时呈降低趋势;同一距离L_(q)/△x不同疏水尺寸的脱离频率在(L_(q)/△x)>0.37(△x<30)时呈先降低后增加趋势,在(L_(q)/△x)≤0.37(△x≥30)时呈增加趋势;同一距离L_(q)/△x不同疏水尺寸的平均热流密度在(L_(q)/△x)>0.37(△x<30)时呈降低趋势,L_(s)=3(L_(s)/L_(q)=0.27)是最佳换热尺寸,在(L_(q)/△x)≤0.37(△x≥30)时呈先增加后降低趋势,L_(s)=5(L_(s)/L_(q)=0.45)为最佳换热尺寸。 展开更多
关键词 格子BOLTZMANN 混合润湿性 生长过程 换热效果 脱离时间
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喀斯特地区土地流转如何促进农户增收?——基于8省3678户的经验证据 被引量:1
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作者 伍国勇 张洲羽 +1 位作者 闵文斌 卢凤雏 《资源开发与市场》 CAS 2024年第7期979-987,共9页
充分发挥喀斯特地区土地流转的农户增收效应是推进山地农业高质量发展的有效渠道。基于中国喀斯特地区8个省区市3 678户农户微观调研数据,采用有序Logit模型、倾向得分匹配法、KHB方法等,考察土地流转对农户收入的影响和作用机制。结果... 充分发挥喀斯特地区土地流转的农户增收效应是推进山地农业高质量发展的有效渠道。基于中国喀斯特地区8个省区市3 678户农户微观调研数据,采用有序Logit模型、倾向得分匹配法、KHB方法等,考察土地流转对农户收入的影响和作用机制。结果表明:(1)土地流转显著提升了喀斯特地区农户家庭总收入水平,土地流转户收入水平较未参与流转户约高出12.86%;(2)相比于土地转入户,土地转出对农户收入增长的影响更为显著;(3)外出务工和家庭创业在土地转出影响农户收入关系中起中介作用,解释比例分别为17.18%和4.63%;农业机械化在耕地较为平整的转入户对收入的影响中起中介作用,解释比例为16.93%;(4)土地流转对种植经济作物、耕地较为平整、灌溉条件较好的农户家庭总收入影响显著为正。为此,建议进一步健全喀斯特地区土地流转机制,促进非农产业发展,加强丘陵山区农业机械化和农田水利设施建设,发展喀斯特地区特色高效农业,鼓励更多农户积极参与土地流转。 展开更多
关键词 农户 土地流转 收入增长 中介效应 喀斯特地区
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Chemical Reaction and Thermal Diffusion Effects on Mass Transfer Flow through an Inclined Plate
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作者 Farjana Akter Md. Manjiul Islam +2 位作者 Ariful Islam Md. Shakhaoath Khan Md. Saddam Hossain 《Open Journal of Fluid Dynamics》 2016年第1期62-74,共13页
A numerical investigation of boundary layer mass transfer flow through an inclined plate with the effect of chemical reaction and thermal diffusion is presented in this study. The governing partial differential equati... A numerical investigation of boundary layer mass transfer flow through an inclined plate with the effect of chemical reaction and thermal diffusion is presented in this study. The governing partial differential equations (PDE) are transformed to a system of dimensionless non-similar coupled PDEs. The transformed, non-similar conservations equations (momentum balance equation, energy balance equation and concentration balance equation) are then solved using a numerical approach known as explicit finite difference method (EFDM). Basically EFDM introduced for the unsteadiness in the momentum, temperature, and concentration fluid fields is based on the time dependent fluid velocity, temperature and concentration of the boundary surface. During the course of discussion, it is found that the various parameters related to the problem influence the calculated resultant expressions. The computed numerical solution results for the velocity, temperature, and concentration distribution with the effect of various important dimensionless parameters (Grashof number, Modified Grashof number, Prandtl number, Schmidt number, Soret number, Dufour number, chemical reaction parameter and inclination parameter) entering into the problems are critically analyzed and discussed graphically. It can be seen that two physical phenomena chemical reaction and thermal diffusion can greatly effect on the boundary layer fluid flows through an inclined plate. 展开更多
关键词 Chemical Reaction Mass transfer Inclined Plate Soret effects Dufour effects
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The water resource transfer in Datong river valley and its effects on ecological environment
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《Global Geology》 1998年第1期54-54,共1页
关键词 The water resource transfer in Datong river valley and its effects on ecological environment
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基于网络效应与行动者效应的专利转让及受让行为研究 被引量:1
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作者 刘晓燕 孙丽娜 +1 位作者 单晓红 杨娟 《科技进步与对策》 CSSCI 北大核心 2024年第2期35-45,共11页
专利交易是技术创新扩散的主要渠道,是实现科技成果转化的有效途径。研究专利转让与受让行为可以识别影响专利交易的主要因素,为政府制定技术交易政策提供科学依据。以2002—2019年中国集成电路产业专利转让记录作为数据源,利用Siena模... 专利交易是技术创新扩散的主要渠道,是实现科技成果转化的有效途径。研究专利转让与受让行为可以识别影响专利交易的主要因素,为政府制定技术交易政策提供科学依据。以2002—2019年中国集成电路产业专利转让记录作为数据源,利用Siena模型,结合网络效应和行动者效应,对专利转让与受让行为影响因素进行实证检验。研究发现:①专利技术交易以单向交易为主,随着集成电路产业从萌芽阶段步入成长阶段,产业内技术交易主体增加,网络规模扩大,网络信息传输效率有所提升,但仍处于较低水平;②网络初期产生的锁定效应明显得以缓解,技术交易网络内组织社团化特征明显,技术交易社团规模呈扩张态势且社团内紧密程度不断提高;③网络效应方面,转让者更倾向于与技术交易伙伴进行交易,频繁发生受让行为的企业会吸引更多新的交易伙伴,企业间不存在明显的互惠交易;④行动者效应方面,随着产业进入成长阶段,成熟企业更倾向于专利转让行为,初创企业更倾向于专利受让行为,占据高结构洞位置的企业更倾向于专利转让行为。企业间技术创新能力差距越小越容易发生技术交易,企业倾向于选择同一国别或同一企业集团内伙伴进行交易。 展开更多
关键词 网络效应 行动者效应 专利转让 专利受让 技术交易 科技成果转化
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