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桥梁隧道 3

三峡工程 2

工程管理 2

渤海海峡 2

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HMAC-SM3；侧信道分析；相关能量攻击；基于比特值的选择明文 1

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Z干扰信道；非正则信号；和速率；帕累托边界；协方差；伪协方差 1

β-粒子的横向振动 1

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Nucleate boiling in two types of vertical narrow channels

Lei GUO, Shusheng ZHANG, Lin CHENG

《能源前沿（英文）》 2011年 第5卷 第3期   页码 250-256 doi: 10.1007/s11708-010-0128-4

摘要： To explore the mechanism of boiling bubble dynamics in narrow channels, we investigate 2-mm wide I- and Z-shaped channels. The influence of wall contact angle on bubble generation and growth is studied using numerical simulation. The relationships between different channel shapes and the pressure drop are also examined, taking into account the effects of gravity, surface tension, and wall adhesion. The wall contact angle imposes considerable influence over the morphology of bubbles. The smaller the wall contact angle, the rounder the bubbles, and the less time the bubbles take to depart from the wall. Otherwise, the bubbles experience more difficulty in departure. Variations in the contact angle also affect the heat transfer coefficient. The greater the wall contact angle, the larger the bubble-covered area. Therefore, wall thermal resistance increases, bubble nucleation is suppressed, and the heat transfer coefficient is lowered. The role of surface tension in boiling heat transfer is considerably more important than that of gravity in narrow channels. The generation of bubbles dramatically disturbs the boundary layer, and the bubble bottom micro-layer can enhance heat transfer. The heat transfer coefficient of Z-shaped channels is larger than that of the I-shaped type, and the pressure drop of the former is clearly higher.

关键词： nucleate boiling     narrow channel     numerical simulation     bubble dynamics    

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Flow characteristics of single-phase flow in narrow annular channels

ZENG Heyi, SU Guanghui, JIA Dounan

《能源前沿（英文）》 2008年 第2卷 第4期   页码 466-470 doi: 10.1007/s11708-008-0101-7

摘要： The characteristics of single-phase flow in narrow annular channels were analyzed and theoretical model was proposed. Based on the present model, the theoretical calculation was performed to predict the flow characteristics for the developed flow in narrow annuli with the gap sizes of 1.0, 1.5 and 2.0 mm, respectively. The results were in good agreement with the experimental data. In addition, the gap size of narrow annuli has great impact upon the flow characteristics. The decrease of gap size reduces friction factor. The higher the Reynolds number, the more remarkable the effect of gap size upon friction coefficient during single-phase flowing through narrow annular channels. The effect of gap size upon friction coefficient is dependent on the Reynolds number, and will decrease with the decrease of the Reynolds number.

关键词： narrow annuli     remarkable     mm     developed     friction    

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Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gasesusing line-by-line and statistical narrow-band models

Huaqiang CHU, Mingyan GU, Huaichun ZHOU, Fengshan LIU

《能源前沿（英文）》 2014年 第8卷 第1期   页码 41-48 doi: 10.1007/s11708-013-0292-4

摘要： Narrow-band transmissivities in the spectral range of 150 to 9300 cm and at a uniform resolution of 25 cm were calculated using the statistical narrow-band (SNB) model with the band parameters of Soufiani and Taine, the more recent parameters of André and Vaillon, and the line-by-line (LBL) method along with the HITEMP-2010 spectroscopic database. Calculations of narrow-band transmissivity were conducted for gas columns of different lengths and containing different isothermal and non-isothermal CO -H O-N mixtures at 1 atm. Narrow-band transmissivities calculated by the SNB model are in large relative error at many bands. The more recent SNB model parameters of André and Vaillon are more accurate than the earlier parameters of Soufiani and Taine. The Planck mean absorption coefficients of CO , H O, CO, and CH in the temperature range of 300 to 2500 K were calculated using the LBL method and different versions of the high resolution transmission (HITRAN) and high-temperature spectroscopic absorption parameters (HITEMP) spectroscopic databases. The SNB model was also used to calculate the Planck mean absorption coefficients of these four radiating gases. The LBL results of the Planck mean absorption coefficient were compared with the classical results of Tien and those from the SNB model.

关键词： transimissity     HITEMP     HITRAN     Planck mean absorption coefficients    

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β-粒子在穿越铜狭缝中的横向台阶分布

朱永强,郝建宇

《中国工程科学》 2008年 第10卷 第8期   页码 81-86

摘要：

文章研究了电子高速运动时所产生的横向振动。实验方法是利用半圆聚焦β-谱仪上90Sr源β-粒子在不同磁场下对于相同弯曲半径下β-粒子具有不同的能量和动量的特性，研究这些β-粒子在通过不同宽度的铜狭缝（厚8 mm）时的粒子数n和铜狭缝宽度δ的函数关系，发现不管β-粒子具有什么能量和动量，都具有横向运动的趋势和在铜狭缝中出现了台阶分布。其原因可能是β-粒子本身具有横向振幅A和周围真空起伏能量的相互作用。

关键词： β-粒子的横向振动     铜狭缝宽度     横向台阶分布    

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Cyclic behavior of stiffened joints between concrete-filled steel tubular column and steel beam with narrow

Chunyan QUAN,Wei WANG,Jian ZHOU,Rong WANG

《结构与土木工程前沿（英文）》 2016年 第10卷 第3期   页码 333-344 doi: 10.1007/s11709-016-0357-7

摘要： This paper presented an investigation on a stiffened joint in practical engineering which was between concrete-filled steel tubular column and steel beam with narrow outer diaphragm and partial joint penetration welds. Through the low-frequency cyclic loading test, the cyclic behavior and failure mode of the specimen were investigated. The results of the test indicated the failure mode and bearing capacity of the specimen which were influenced by the axial compression ratio of the concrete-filled tubular column. On the contrary, the inner diaphragm and inner stiffeners had limited impacts on the hysteretic behavior of the joint. There was no hysteresis damage fracture on the narrow outer diaphragm connected to the concrete-filled steel tubular column with partial joint penetration welds. Due to the excellent ductility and energy dissipating capacity, the proposed joint could be applied to the seismic design of high-rise buildings in highly intensive seismic region, but axial compression ratio should be controlled to avoid unfavorable failure modes.

关键词： narrow outer diaphragm     concrete-filled tubular column     joint     inner and outer stiffening     cyclic behavior    

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Numerical investigation on the dryout point of annular flow in the upward narrow annuli with bilateral

SU Guanghui, QIU Suizheng, DUAN Feng, XIAO Zejun, HUANG Yanping

《能源前沿（英文）》 2007年 第1卷 第3期   页码 264-272 doi: 10.1007/s11708-007-0037-3

摘要： Based on the fundamental conservation principles—the mass, momentum, and energy conservation equtions of liquid films and the momentum conservation equation of vapor core, a theoretical three-fluid model has been developed to predict the dryout point of upward annular flow in vertical narrow annuli with bilateral heating. The range of the parameters are: pressure from 0.5 to 5.0 MPa; mass flow rate from 30 to 150 kg/(m · s); gap size from 1.2 to 2.0 mm. Through numerically solving the model, the relationships among the parameters of the critical quality (), critical heat flux (), mass flow rate, system pressure, and the ratio of heat flux on the inner wall of the outer tube to that on the outer wall of the inner tube (/) are obtained and analyzed. The predicted results accurately match with the experimental data. For a fixed , will increase with the decreases in the gap size and the tube curvature when the dryout point occurs on the outer wall of the inner tube. However, for a fixed , when the dryout point occurs on the inner wall of the outer tube, the parametric trend is reverse. When the dryout point on the inner and outer walls occurs simultaneously, reaches a peak value, and the ratio of / at this position changes with the gap size and the tube curvature.
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Nongray radiation from gas and soot mixtures in planar plates based on statistical narrow-band spectral

Huaqiang CHU, Qiang CHENG, Huaichun ZHOU, Fengshan LIU

《能源前沿（英文）》 2011年 第5卷 第2期   页码 149-158 doi: 10.1007/s11708-010-0124-8

摘要： The nongray behavior of combustion products plays an important role in various areas of engineering. Based on the statistical narrow-band (SNB) spectral model with an exponential-tailed inverse intensity distribution and the ray-tracing method, a comprehensive investigation of the influence of soot on nongray radiation from mixtures containing H O/N +soot, CO /N +soot, or H O/CO /N +soot was conducted in this paper. In combustion applications, radiation transfer is significantly enhanced by soot due to its spectrally continuous emission. The effect of soot volume fraction up to 1×10 on the source term, the narrow-band radiation intensities along a line-of-sight, and the net wall heat fluxes were investigated for a wide range of temperature. The effect of soot was significant and became increasingly drastic with the increase of soot loading.

关键词： soot     combustion     SNB model     nongray radiation    

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Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

Hanyang XU, Tielin SHI, Guanglan LIAO, Qi XIA

《机械工程前沿（英文）》 2019年 第14卷 第2期   页码 235-240 doi: 10.1007/s11465-017-0458-6

摘要： We describe the formation of nested wrinkles created by the thermal mismatch between a narrow-band thin film and a compliant substrate. When a film is described as “narrow-band”, it literally means that the film band width is much shorter than its length; more precisely, it means that the width is comparable with the wavelength of the wrinkles. A silicon mask was used during film sputtering to create narrow-band films on poly (dimethylsiloxane) substrate, thus creating regular boundaries to steer local stresses and control wrinkle morphology. Disordered nano-scale wrinkles were found nested within highly ordered micro-scale sinusoidal wrinkles. The formation of nested wrinkles was explained through the amplitude and wavelength saturation of nano-scale wrinkles. The disordered morphology of nano-scale wrinkles and the highly ordered morphology of micro-scale wrinkles were explained by using the boundary effect.

关键词： nested and hierarchical wrinkles     morphology     amplitude saturation     boundary effect    

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Improvement in growth yield of single-walled carbon nanotubes with narrow chirality distribution by pulse

Bin Xu, Toshiro Kaneko, Toshiaki Kato

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 485-492 doi: 10.1007/s11705-019-1831-2

摘要： A pulse plasma chemical vapor deposition (CVD) technique was developed for improving the growth yield of single-walled carbon nanotubes (SWNTs) with a narrow chirality distribution. The growth yield of the SWNTs could be improved by repetitive short duration pulse plasma CVD, while maintaining the initial narrow chirality distribution. Detailed growth dynamics is discussed based on a systematic investigation by changing the pulse parameters. The growth of SWNTs with a narrow chirality distribution could be controlled by the difference in the nucleation time required using catalysts comprising relatively small or large particles as the key factor. The nucleation can be controlled by adjusting the pulse on/off time ratio and the total processing time.

关键词： single-walled carbon nanotubes     chirality-controlled synthesis     pulse plasma chemical vapor deposition    

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A cellphone-based colorimetric multi-channel sensor for water environmental monitoring

《环境科学与工程前沿（英文）》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1590-z

摘要：

● A cellphone-based colorimetric multi-channel sensor for in-field detection.

关键词： Colorimetric analysis     Multi-channel sensor     Cellphone     Water quality indexes     Environmental monitoring    

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Analysis of nonlinear channel friction inverse problem

CHENG Weiping, LIU Guohua

《结构与土木工程前沿（英文）》 2007年 第1卷 第2期   页码 205-210 doi: 10.1007/s11709-007-0024-0

摘要： Based on the Backus-Gilbert inverse theory, the singular value decomposition (SVD) for general inverse matrices and the optimization algorithm are used to solve the channel friction inverse problem. The resolution and covariance friction inverse model in matrix form is developed to examine the reliability of solutions. Theoretical analyses demonstrate that the convergence rate of the general Newton optimization algorithm is in the second-order. The Wiggins method is also incorporated into the algorithm. Using the method, noise can be suppressed effectively, and the results are close to accurate solutions with proper control parameters. Also, the numerical stability can be improved.

关键词： singular     SVD     second-order     covariance     Theoretical    

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Fluorene-based narrow-band-gap copolymers for red light-emitting diodes and bulk heterojunction photovoltaic

SUN Mingliang, WANG Li, XIA Yangjun, DU Bin, LIU Ransheng, CAO Yong

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 257-264 doi: 10.1007/s11705-008-0052-x

摘要： A series of narrow band-gap conjugated copolymers (PFO-DDQ) derived from 9,9-dioctylfluorene (DOF) and 2,3-dimethyl-5,8-dithien-2-yl-quinoxalines (DDQ) is prepared by the palladium-catalyzed Suzuki coupling reaction with the molar feed ratio of DDQ at around 1%, 5%, 15%, 30% and 50%, respectively. The obtained polymers are readily soluble in common organic solvents. The solutions and the thin solid films of the copolymers absorb light from 300–590 nm with two absorbance peaks at around 380 and 490 nm. The intensity of 490 nm peak increases with the increasing DDQ content in the polymers. Efficient energy transfer due to exciton trapping on narrow-band-gap DDQ sites has been observed. The PL emission consists exclusively of DDQ unit emission at around 591–643 nm depending on the DDQ content in solid film. The EL emission peaks are red-shifted from 580 nm for PFO-DDQ1 to 635 nm for PFO-DDQ50. The highest external quantum efficiency achieved with the device configuration ITO/PEDOT/PVK/PFO-DDQ15/Ba/Al is 1.33% with a luminous efficiency 1.54 cd/A. Bulk heterojunction photovoltaic cells fabricated from composite films of PFO-DDQ30 copolymer and [6,6]-phenyl C butyric acid methyl ester (PCBM) as electron donor and electron acceptor, respectively in device configuration: ITO/PEDOT:PSS/PFO-DDQ30:PCBM/PFPNBr/Al shows power conversion efficiencies of 1.18% with open-circuit voltage () of 0.90 V and short-circuit current density () of 2.66 mA/cm under an AM1.5 solar simulator (100 mW/cm). The photocurrent response wavelengths of the PVCs based on PFO-DDQ30/PCBM blends covers 300–700 nm. This indicates that these kinds of low band-gap polymers are promising candidates for polymeric solar cells and red light-emitting diodes.

关键词： simulator     Efficient     band-gap     PFO-DDQ50     intensity    

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钽基氮氧化物——窄带隙光催化剂用于太阳能制氢 Review

肖慕, 王松灿, Thaweesak Supphasin, 罗彬, 王连洲

《工程（英文）》 2017年 第3卷 第3期   页码 365-378 doi: 10.1016/J.ENG.2017.03.019

摘要：

光催化分解水可以将太阳能直接转化为氢能，是一种有效利用太阳能的途径。开发用于太阳能制氢的高效且稳定的光催化剂是光催化研究领域的重要目标之一。钽基氮氧化物具有窄的带隙宽度，并且光生电子和空穴的势能足够用来分解水，因此该类光催化剂最有可能实现太阳能制氢。到目前为止，全世界的研究小组对钽基氮氧化物光催化剂进行了系统而深入的研究，取得了大量的成果。然而，钽基氮氧化物的太阳能制氢效率还远远低于理论值。如何更好地设计这些材料进而提高其太阳能制氢效率这一命题是十分重要和有意义的。本文总结了钽基氮氧化物用于光催化制氢的研究和发展过程，着重分析了用于提高光催化分解水效率的各种方法。最后，探讨了窄带隙钽基氮氧化物光催化分解水研究领域的未来发展趋势。

关键词： 钽基光催化剂     窄带隙     分解水     氢    

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Improvement of solidification model and analysis of 3D channel blockage with MPS method

《能源前沿（英文）》 2021年 第15卷 第4期   页码 946-958 doi: 10.1007/s11708-021-0754-z

摘要： In a severe accident of a nuclear power reactor, coolant channel blockage by solidified molten core debris may significantly influence the core degradations that follow. The moving particle semi-implicit (MPS) method is one of the Lagrangian-based particle methods for analyzing incompressible flows. In the study described in this paper, a novel solidification model for analyzing melt flowing channel blockage with the MPS method has been developed, which is suitable to attain a sufficient numerical accuracy with a reasonable calculation cost. The prompt velocity diffusion by viscosity is prioritized over the prompt velocity correction by the pressure term (for assuring incompressibility) within each time step over the “mushy zone” (between the solidus and liquidus temperature) for accurate modeling of solidification before fixing the coordinates of the completely solidified particles. To sustain the numerical accuracy and stability, the corrective matrix and particle shifting techniques have been applied to correct the discretization errors from irregular particle arrangements and to recover the regular particle arrangements, respectively. To validate the newly developed algorithm, 2-D benchmark analyses are conducted for steady-state freezing of the water in a laminar flow between two parallel plates. Furthermore, 3-D channel blockage analyses of a boiling water reactor (BWR) fuel support piece have been performed. The results show that a partial channel blockage develops from the vicinity of the speed limiter, which does not fully develop into a complete channel blockage, but still diverts the incoming melt flow that follows to the orifice region.

关键词： boiling water reactor (BWR)     severe accident     channel blockage     moving particle semi-implicit (MPS) method     solidification    

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Experimental investigation of liquid metal alloy based mini-channel heat exchanger for high power electronic

Manli LUO, Jing LIU

《能源前沿（英文）》 2013年 第7卷 第4期   页码 479-486 doi: 10.1007/s11708-013-0277-3

摘要： There is currently a growing demand for developing efficient techniques for cooling integrated electronic devices with ever increasing heat generation power. To better tackle the high-density heat dissipation difficulty within the limited space, this paper is dedicated to clarify the heat transfer behaviors of the liquid metal flowing in mini-channel exchangers with different geometric configurations. A series of comparative experiments using liquid metal alloy Ga68%In20%Sn12% as coolant were conducted under prescribed mass flow rates in three kinds of heat exchangers with varied geometric sizes. Meanwhile, numerical simulations for the heat exchangers under the same working conditions were also performed which well interpreted the experimental measurements. The simulated heat sources were all cooled down by these three heat dissipation apparatuses and the exchanger with the smallest channel width was found to have the largest mean heat transfer coefficient at all conditions due to its much larger heat transfer area. Further, the present work has also developed a correlation equation for characterizing the Nusselt number depending on Peclet number, which is applicable to the low Peclet number case with constant heat flux in the hydrodynamically developed and thermally developing region in the rectangular channel. This study is expected to provide valuable reference for designing future liquid metal based mini-channel heat exchanger.

关键词： heat exchanger     liquid metal     mini-channel     heat dissipation     heat transfer coefficient    

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标题 作者 时间 类型 操作

Nucleate boiling in two types of vertical narrow channels

Lei GUO, Shusheng ZHANG, Lin CHENG

期刊论文

Flow characteristics of single-phase flow in narrow annular channels

ZENG Heyi, SU Guanghui, JIA Dounan

期刊论文

Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gasesusing line-by-line and statistical narrow-band models

Huaqiang CHU, Mingyan GU, Huaichun ZHOU, Fengshan LIU

期刊论文

β-粒子在穿越铜狭缝中的横向台阶分布

朱永强,郝建宇

期刊论文

Cyclic behavior of stiffened joints between concrete-filled steel tubular column and steel beam with narrow

Chunyan QUAN,Wei WANG,Jian ZHOU,Rong WANG

期刊论文

Numerical investigation on the dryout point of annular flow in the upward narrow annuli with bilateral

SU Guanghui, QIU Suizheng, DUAN Feng, XIAO Zejun, HUANG Yanping

期刊论文

Nongray radiation from gas and soot mixtures in planar plates based on statistical narrow-band spectral

Huaqiang CHU, Qiang CHENG, Huaichun ZHOU, Fengshan LIU

期刊论文

Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

Hanyang XU, Tielin SHI, Guanglan LIAO, Qi XIA

期刊论文

Improvement in growth yield of single-walled carbon nanotubes with narrow chirality distribution by pulse

Bin Xu, Toshiro Kaneko, Toshiaki Kato

期刊论文

A cellphone-based colorimetric multi-channel sensor for water environmental monitoring

期刊论文

Analysis of nonlinear channel friction inverse problem

CHENG Weiping, LIU Guohua

期刊论文

Fluorene-based narrow-band-gap copolymers for red light-emitting diodes and bulk heterojunction photovoltaic

SUN Mingliang, WANG Li, XIA Yangjun, DU Bin, LIU Ransheng, CAO Yong

期刊论文

钽基氮氧化物——窄带隙光催化剂用于太阳能制氢

肖慕, 王松灿, Thaweesak Supphasin, 罗彬, 王连洲

期刊论文

Improvement of solidification model and analysis of 3D channel blockage with MPS method

期刊论文

Experimental investigation of liquid metal alloy based mini-channel heat exchanger for high power electronic

Manli LUO, Jing LIU

期刊论文