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转光农膜的光谱特性研究 被引量:16
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作者 张颂培 李建宇 +2 位作者 陈娟 肖阳 孙玉娥 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2004年第10期1180-1184,共5页
通过太阳光谱以及菊花、番茄作用光谱的测试分析 ,讨论了植物生长与太阳光谱的关系 ,表明太阳光谱中 2 80~ 380nm的紫外光 ,5 0 0~ 6 0 0nm的绿黄光及 72 0nm以上近红外光植物利用率较低 ,4 30~ 4 80nm的蓝紫光和 6 30~ 6 90nm的红... 通过太阳光谱以及菊花、番茄作用光谱的测试分析 ,讨论了植物生长与太阳光谱的关系 ,表明太阳光谱中 2 80~ 380nm的紫外光 ,5 0 0~ 6 0 0nm的绿黄光及 72 0nm以上近红外光植物利用率较低 ,4 30~ 4 80nm的蓝紫光和 6 30~ 6 90nm的红光有利于增强光合作用。依据植物光合作用和太阳光谱特征 ,设计出CaS∶Cu+ ,Cl-蓝光膜 ,利用CaS∶Eu2 + ,Mn2 + ,Cl-,设计出绿光转红光的红光膜。讨论了红蓝复合双峰增益膜及紫外光转红光的稀土有机配合物的光谱特性。农用光能转换剂研制面临新的突破 。 展开更多
关键词 光农膜 光谱特性 植物 生长 太阳光谱 光合作用 反Stocks位移技术 红外光红光膜
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The Singularly Perturbed Boundary Value Problems for Elliptic Equation with Turning Point 被引量:1
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作者 陈松林 莫嘉琪 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期12-16,共5页
The singularly perturbed elliptic equation boundary value problem with turning point is considered. Using the method of multiple scales and the comparison theorem, the asymptotic behavior of solution for the boundary ... The singularly perturbed elliptic equation boundary value problem with turning point is considered. Using the method of multiple scales and the comparison theorem, the asymptotic behavior of solution for the boundary value problem is studied. 展开更多
关键词 singular perturbation boundary value problem elliptic equation
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最新旱冰技术——(连载之六)
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作者 王树本 《冰雪运动》 1985年第3期41-44,共4页
(八)括弧形括弧形也是带有转体的图形,它的尖端不象3字形那样对着圆心,而是背向国心,尖端对着圆外,尖端也是在纵轴上,但这个转体技术要比3字形困难得多,上体的转动方向与圆的滑行方向完全相反。尖端的大小与3字形相同。根据用刃不同,可... (八)括弧形括弧形也是带有转体的图形,它的尖端不象3字形那样对着圆心,而是背向国心,尖端对着圆外,尖端也是在纵轴上,但这个转体技术要比3字形困难得多,上体的转动方向与圆的滑行方向完全相反。尖端的大小与3字形相同。根据用刃不同,可分为:①前外括弧;②前内活弧;③后外括弧;④后内括弧。关于转尖时的要求,请参阅3字转体的技术要求。括弧形的正确几何形见图。 展开更多
关键词 动方向 请参阅 技术要求 内勾 后交叉 手形 起滑 练习方法 近转 看线
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Extension of analytical model of solid-state phase transformation 被引量:1
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作者 姜伊辉 刘峰 宋韶杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1176-1181,共6页
Departing from an analytical phase transformation model, a new analytical approach to deduce transformed fraction for non-isothermal phase transformation was developed. In the new approach, the effect of the initial t... Departing from an analytical phase transformation model, a new analytical approach to deduce transformed fraction for non-isothermal phase transformation was developed. In the new approach, the effect of the initial transformation temperature and the accurate "temperature integral" approximations are incorporated to obtain an extended analytical model. Numerical approach demonstrated that the extended analytical model prediction for transformed fraction and transformation rate is in good agreement with the exact numerical calculation. The new model can describe more precisely the kinetic behavior than the original analytical model, especially for transformation with relatively high initial transformation temperature. The kinetic parameters obtained from the new model are more accurate and reasonable than those from the original analytical model. 展开更多
关键词 non-isothermal transformation analytical model initial transformation temperature APPROXIMATION
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Capacitor self-calibration technique used in time-interleaved successive approximation ADC
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作者 殷勤 戚韬 +1 位作者 吴光林 吴建辉 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期164-168,共5页
A capacitor self-calibration circuit used in a successive approximation analog-to-digital converter (SA-ADC) is presented. This capacitor self-calibration circuit can calibrate erroneous data and work with the ADC b... A capacitor self-calibration circuit used in a successive approximation analog-to-digital converter (SA-ADC) is presented. This capacitor self-calibration circuit can calibrate erroneous data and work with the ADC by adding an additional clock period. This circuit is used in a 10 bit 32 Msample/s time-interleaved SA- ADC. The chip is implemented with Chart 0. 25 μm 2. 5 V process and totally occupies an area of 1.4 mm× 1.3 mm. After calibration, the simulated signal-to-noise ratio (SNR) is 59. 586 1 dB and the spurious-free dynamic range (SFDR) is 70. 246 dB at 32 MHz. The measured signal-to-noise and distortion ratio (SINAD) is 44. 82 dB and the SFDR is 63. 760 4 dB when the ADC samples a 5.8 MHz sinusoid wave. 展开更多
关键词 capacitor self-calibration analog-to-digital converter successive approximation time-interleaved
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Quantum Collapse and Revival of Atom in Mode-Mode Competing System 被引量:2
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作者 WUQin FANGMao-Fa 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期515-518,共4页
The atomic inversion dynamics in the mode-mode competing system is studied bymeans of fully quantum theory. A general solution to the Schroedinger equation of this system isobtained. The influence of the relative comp... The atomic inversion dynamics in the mode-mode competing system is studied bymeans of fully quantum theory. A general solution to the Schroedinger equation of this system isobtained. The influence of the relative competing strength between the atom and the two-mode Geld onthe atomic inversion is disccussed. We show that the presence of the mode-mode competition canresult in periodical collapses-revivals of the atomic inversion. 展开更多
关键词 two-mode competition model atomic inversion collapse and revival
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Generalized Variational Iteration Solution of Soliton for Disturbed KdV Equation 被引量:24
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作者 莫嘉琪 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第3期440-442,共3页
The corresponding solution for a class of disturbed KdV equation is considered using the analytic method. From the generalized variational iteration theory, the problem of solving soliton for the corresponding equatio... The corresponding solution for a class of disturbed KdV equation is considered using the analytic method. From the generalized variational iteration theory, the problem of solving soliton for the corresponding equation translates into the problem of variational iteration. And then the approximate solution of the soliton for the equation is obtained. 展开更多
关键词 SOLITON disturbed variational iteration
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Mismatch Calibration Techniques in Successive Approximation Analog-to-Digital Converters
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作者 王沛 龙善丽 吴建辉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第9期1369-1374,共6页
Comparator offset cancellation and capacitor self-calibration techniques used in a successive approximation analog-to-digital converter (SA-ADC) are described. The calibration circuit works in parallel with the SAAD... Comparator offset cancellation and capacitor self-calibration techniques used in a successive approximation analog-to-digital converter (SA-ADC) are described. The calibration circuit works in parallel with the SAADC by adding additional calibration clock cycles to pursue high accuracy and low power consumption, and the calibrated resolution can be up to 14bit. This circuit is used in a 10bit 3Msps successive approximation ADC. This chip is realized with an SMIC 0. 18μm 1.8V process and occupies 0.25mm^2 . It consumes 3. 1mW when operating at 1.8MHz. The measured SINAD is 55. 9068dB, SFDR is 64. 5767dB, and THD is - 74. 8889dB when sampling a 320kHz sine wave. 展开更多
关键词 analog-to-digital converter successive approximation self-calibration techniques
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Near Resonant Electronic and Rotational Energy Transfer AB(^1∏, J)+C(^slj)→AB(^1∏, J')+C(^sl j') 被引量:4
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作者 WANGWei-Li SONGPeng SHENYang MAFeng-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期879-885,共7页
In our previous theoretical study, the theoretical model of thecollision-induced electronic and rotational energy transfer of AB(~1Σ, J) + C(~sl_j) → AB(~1Σ,J′) + C(~sl_(j′)) was presented. To further study the c... In our previous theoretical study, the theoretical model of thecollision-induced electronic and rotational energy transfer of AB(~1Σ, J) + C(~sl_j) → AB(~1Σ,J′) + C(~sl_(j′)) was presented. To further study the collision-induced electronic and rotationalenergy transfer theoretically on AB( ~1Π, J) + C(~sl_j) → AB( ~1Π, J′) + C(~sl_(j′)), atheoretical model is presented, based on the time-dependent first-order Born approximation, takinginto account the anisotropic Lennard-Jones interaction potential and 'straight-line' trajectoryapproximation. The changing tendency of the transitional probabilities with the anisotropicparameter is discussed. 展开更多
关键词 quantum interference rotational energy transfer near resonant electronic
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Research on temperature profiles of honeycomb regenerator with asymptotic analysis
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作者 艾元方 《Journal of Chongqing University》 CAS 2006年第2期77-82,共6页
An asymptotic semi-analytical method for heat transfer in counter-flow honeycomb regenerator is proposed. By introducing a combined heat-transfer coefficient between the gas and solid phase, a heat transfer model is b... An asymptotic semi-analytical method for heat transfer in counter-flow honeycomb regenerator is proposed. By introducing a combined heat-transfer coefficient between the gas and solid phase, a heat transfer model is built based on the thin-walled assumption. The dimensionless thermal equation is deduced by considering solid heat conduction along the passage length. The asymptotic analysis is used for the small parameter of heat conduction term in equation. The first order asymptotic solution to temperature distribution under weak solid heat conduction is achieved after Laplace transformation through the multiple scales method and the symbolic manipulation function in MATLAB. Semi-analytical solutions agree with tests and finite-difference numerical results. It is proved possible for the asymptotic analysis to improve the effectiveness, economics and precision of thermal research on regenerator. 展开更多
关键词 honeycomb regenerator temperature profile asymptotic analysis
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Exploring Solutions of Nonlinear Rossby Waves with Complete Coriolis Force
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作者 ZHAO Qiang YU Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第7期185-188,共4页
Nonlinear Rossby waves in a Boussinesq fluid model which includes both the vertical and horizontalcomponents of Coriolis force are studied by using the semi-geostrophic approximation and the method of travelling-waves... Nonlinear Rossby waves in a Boussinesq fluid model which includes both the vertical and horizontalcomponents of Coriolis force are studied by using the semi-geostrophic approximation and the method of travelling-wavesolution.Taylor series expansion has been employed to isolate the characteristics of the linear Rossby waves and identifythe Rossby cnoidal and solitary waves.Qualitative analysis indicates that if the disturbances are independent of latitude,the effect of horizontal components of Coriolis force disappears. 展开更多
关键词 Coriolis force Rossby waves semi-geostrophic approximation
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An Explicit Backlund Transformation of Burgers Equation with Applications 被引量:1
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作者 LU Zhuo-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第6X期987-989,共3页
In this paper, an explicit Bgcklund transformation (BT) of the Burgers equation is obtained by using the further extended tanh method [Phys. Lett. A 307 (2003) 269; Chaos, Solitons & Fractals 17 (2003) 669]. Ba... In this paper, an explicit Bgcklund transformation (BT) of the Burgers equation is obtained by using the further extended tanh method [Phys. Lett. A 307 (2003) 269; Chaos, Solitons & Fractals 17 (2003) 669]. Based on the BT and some newly obtained seed solutions, infinite sequences of exact solutions for the Burgers equation are generated. Further more, this BT of the Burgers equation is applied to solve the variant Boussinesq equations and the approximate equations of long water wave. 展开更多
关键词 Burgers equation Backlund transformation exact solution
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Inverse Theorem of Approximation in L_p for the Stancu Integral-type Operators on a Simplex
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作者 ZHANG Chun-gou 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期4-9,共6页
In this paper, the integral-type Stancu operators on a simplex is considered and its inverse theorem of approximation in Lp(1≤ p 〈+∞)has been obtained.
关键词 SIMPLEX K-FUNCTIONAL the integral-type Stancu operators inverse theorem of approximation
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如何接好中路近网的不转球
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作者 李克菲 《乒乓世界》 2003年第4期53-53,共1页
关键词 乒乓球 接球技术 中路网不 横板技术
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Theoretical investigation of micropolar fluid flow between two porous disks 被引量:6
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作者 P.Valipour S.E.Ghasemi M.Vatani 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2825-2832,共8页
The steady, laminar, incompressible and two dimensional micropolar flow between two porous disks was investigated using optimal homotopy asymptotic method(OHAM) and fourth order Runge–Kutta numerical method. Comparis... The steady, laminar, incompressible and two dimensional micropolar flow between two porous disks was investigated using optimal homotopy asymptotic method(OHAM) and fourth order Runge–Kutta numerical method. Comparison between OHAM and numerical method shows that OHAM is an exact and high efficient method for solving these kinds of problems. The results are presented to study the velocity and rotation profiles for different physical parameters such as Reynolds number, vortex viscosity parameter, spin gradient viscosity and microinertia density parameter. As an important outcome, the magnitude of the microrotation increases with an increase in the values of injection velocity while it decreases by increasing the values of suction velocity. 展开更多
关键词 theoretical investigation porous disks micropolar fluid flow optimal homotopy asymptotic method(OHAM) microrotation
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Turbidity analysis using visible and near-infrared light images 被引量:2
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作者 ZHU Yuanyang ZHAO Wenzhu +1 位作者 LIU Sheng GAO Hongwen 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第1期27-35,共9页
The conventional photoelectric detection system requires complex circuitry and spectroscopic systems as well as specialized personnel for its operation.To replace such a system,a method of measuring turbidity using a ... The conventional photoelectric detection system requires complex circuitry and spectroscopic systems as well as specialized personnel for its operation.To replace such a system,a method of measuring turbidity using a camera is proposed by combining the imaging characteristics of a digital camera and the high-speed information processing capability of a computer.Two turbidity measurement devices based on visible and near-infrared(NIR)light cameras and a light source driving circuit with constant light intensity were designed.The RGB data in the turbidity images were acquired using a self-developed image processing software and converted to the CIE Lab color space.Based on the relationship between the luminance,chromatic aberration,and turbidity,the turbidity detection models for luminance and chromatic aberration of visible and NIR light devices exhibiting values from 0-1000 NTU,less than 100 NTU,and more than 100 NTU were established.By comparing and analyzing the proposed models,the two measurement models with the best all-around performance were selected and fused to generate new measurement models.The experimental results prove that the correlation between the three models and the commercial turbidity meter measurements exhibite a significance value higher than 0.999.The error of the fusion model is within 1.05%,with a mean square error of 1.14.The visible light device has less error at low turbidity measurements and is less influenced by the color of the image.The NIR light device is more stable and accurate at full range and high turbidity measurements and is therefore more suitable for such measurements. 展开更多
关键词 image processing water quality turbidity measurement near-infrared image color space conversion
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Different Kinds of Discrete Breathers in Three Types of One-Dimensional Models
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作者 吕彬彬 田强 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期728-734,共7页
The dynamics of different kinds of discrete breathers in three types of one-dimensionai monatomic chains with on-site and inter-site potentiais are investigated. The existence and evolution of symmetric breather, anti... The dynamics of different kinds of discrete breathers in three types of one-dimensionai monatomic chains with on-site and inter-site potentiais are investigated. The existence and evolution of symmetric breather, antisymmetric breather, and multibreather in one-dimensionai models are proved by using rotating wave approximation, local anharmonic approximation, and the numerical method. The linear stability of these breathers is investigated by using Lyapunov stable anaiysis. The localization and stability of breathers in three types of models correlate closely to the system nonlinear parameter β. 展开更多
关键词 symmetric breather antisymmetric breather multibreather linear stability
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Laser pulse design for coherent laser control of potassium atoms
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作者 张现周 贾光瑞 何海芳 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2349-2355,共7页
In this paper, the dynamics of coherent laser control of potassium atoms is studied by using the time-dependent multilevel approach (TDMA). The calculation results of population transfer are presented with different... In this paper, the dynamics of coherent laser control of potassium atoms is studied by using the time-dependent multilevel approach (TDMA). The calculation results of population transfer are presented with different laser fields. The results show that the population can be transferred to target state completely by a specially designed laser field. 展开更多
关键词 time-dependent multilevel approach (TDMA) coherent laser control population transfer specially designed laser field
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Interference Angle on Quantum Rotational Energy Transfer in Na+Na_2 (A^1Σ_u^+,v = 8~b^3Π_(Ou), v = 14) Molecular Collision System
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作者 WANG Wei-Li MIAO Gang +1 位作者 LI Jian MA Feng-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第12期1062-1066,共5页
In order to study the collisional quantum interference (CQI) on rotational energy transfer in atom-diatom system, we have studied the relation of the integral interference angle and differential interference angle i... In order to study the collisional quantum interference (CQI) on rotational energy transfer in atom-diatom system, we have studied the relation of the integral interference angle and differential interference angle in Naq-Na2 (A1 ∑u^+,v=8-b^3∏0u,v=14) collision system. In this paper, based on the first-Born approximation of timedependent perturbation theory and taking into accounts the anisotropic effect of Lennard-Jones interaction potentials, we present a theoretical model of collisional quantum interference in intramolecular rotational energy transfer, and a relationship between differential and integral interference angles. 展开更多
关键词 rotation energy transfer integral interference angle differential interference angle collision diameter
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Entropy evolution of field with a time-varying frequency in the Jaynes-Cummings model
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作者 Qiu Changdong 《Engineering Sciences》 EI 2012年第2期78-83,共6页
Following Jaynes-Cummings model,the evolution of the field entropy in the system of a two-level atom interacting with the single mode coherent field is investigated under rotating-wave approximation.The typical case &... Following Jaynes-Cummings model,the evolution of the field entropy in the system of a two-level atom interacting with the single mode coherent field is investigated under rotating-wave approximation.The typical case "the field frequency variance with time in the form of sine ω=ω0+usin(wt) has been considered.The influences of the amplitude and angle frequency of the field frequency variance on entropy evolution of the field are discussed by numerical calculations.Calculation results indicate that the field frequency variance influences violently the behavior of field entropy evolution;the larger the amplitude of the field frequency variance is,the stronger the influence of the field frequency variance on the time evolution of field entropy is. 展开更多
关键词 two-level atom Jaynes-Cummings model frequency of field varying with time the evolution of the field entropy
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