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MEASUREMENT AND CORRELATION OF PARTITION coefficients OF UROKINASE IN AQUEOUS TWO-PHASE PEG-POTASSIUM PHOSPHATE SYSTEM

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Chinese Journal of Chemical Engineering 1996年第1期4卷 22-30页

作者：朱自强李勉梅乐和韩兆熊浙江大学化学工程系浙江杭州

Partition coefficients of Urokinase(UK)were measured in aqueous two-phase systems con-taining polyethylene glycol and potassium phosphate at *** on the Diamond-Hsu model,a modified expression was obtained for the correlation of enzyme partitioning in theabove-mentioned *** a modified form,the partitioning data of UK and heteroproteinwere *** results show that the modified model is simple gives good *** will fa-cilitate engineering scale-up of aqueous two-phase systems for certain proteins purification.

关键词： partition coefficients urokinase aqueous two phase system thermodynamic model

Asymptotic Stability of Memory-Type Euler-Bernoulli Plate with Variable coefficients and Time Delay

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Journal of Systems Science & Complexity 2019年第5期32卷 1375-1392页

作者： WANG Peipei HAO Jianghao School of Mathematical Sciences Shanxi University

This paper considers a viscoelastic Euler-Bernoulli plate system with variable coefficients and time-varying delay. By the multiplier method, Riemannian geometry method, and under suitable assumptions on viscoelastic term and time delay, the authors obtain the general stability of the solution for the system which depends on the behavior of the relaxation function.

关键词： Euler-Bernoulli plate general decay rate time-varying delay variable coefficients viscoelastic term

On the coefficients of the polynomial in the number field sieve

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Science China(Information Sciences) 2015年第11期58卷 182-190页

作者： YANG Min MENG QingShu WANG ZhangYi LI Li ZHANG HuanGuo International School of Software Wuhan University Computer School Wuhan University

Polynomial selection is very important in the number field sieve. If the number of relations a pair of polynomials can generate is closely correlated with the coefficients of the polynomials, we can select polynomials by checking the coefficients first, which can speed up the selection of good polynomials. In this paper, we aim to study the correlation between polynomial coefficients and the number of relations the polynomials can generate. By analyzing the zero roots, it is found that a polynomial with the ending coefficient containing more small primes usually can generate more relations than the one whose ending coefficient contains less. As a polynomial with more real roots usually can generate more relations, using the complete discrimination system,the requirements on the coefficients of a polynomial to obtain more real roots are analyzed. For instance, a necessary condition for a polynomial of degree d to have d distinct real roots is that the coefficient of degree d- 2should be negative or small enough. The result in the case d = 3 can be used directly in selecting polynomials generated by the nonlinear method, where d = 3 is already enough for practical purpose.

关键词： cryptography integer factorization number field sieve polynomial selection coefficients zero roots complete discrimination system

Measurement of mass diffusion coefficients of O_2 in aviation fuel through digital holographic interferometry

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Chinese Journal of Aeronautics 2019年第5期32卷 1184-1189页

作者： Chaoyue LI Weihua LIU Xiaotian PENG Lei SHAO Shiyu FENG Key Laboratory of Aircraft Environment Control and Life Support of Ministry of Industry and Information Technology College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

The experimental apparatus to measure the mass diffusion coefficients of O2 in aviation fuel was constructed based on the digital holographic interferometry method. The theory of mass diffusion coefficient and interference image processing were introduced in detail. The accuracy of the experiment was verified by measuring the mass diffusion coefficient of 0.33 mol/L KCl in aqueous solution at 298.15 K. The mass diffusion coefficients of O_2 in RP3 and RP5 aviation fuels were measured at temperature from 278.15 K to 333.15 K, and the Arrhenius equation was employed to fit the experimental data. In terms of the Stokes-Einstein equation, the viscosities of these two aviation fuels were tested to estimate the correlation among mass diffusion coefficient, viscosity and temperature. A uniform polynomial calculation correlation was proposed to predict the mass diffusion coefficients of O_2 in both RP3 and RP5 aviation fuels, and its accuracy is considerably higher than that of the Stokes-Einstein equation.

关键词： Aviation fuel Diffusion coefficients Digital holographic interferometry Oxygen Viscosity

PREDICTION OF THE TEMPERATURE DEPENDENCE OF LIQUID DIFFUSION coefficients AT INFINITE DILUTION BY A GROUP CONTRIBUTION METHOD

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Chinese Journal of Chemical Engineering 1997年第4期5卷 85-88页

作者：何潮洪俞永盛 Department of Chemical Engineering Zhejiang University

1 INTRODUCTIONSince experimental determination of the mutual liquid diffusion coefficients atinfinite dilution is rather complicated,it is important,therefore,to be able to esti-mate the coefficients under various temperatures from one available coefficient ata certain temperature such as *** equations for this purpose are avail-able in many *** examples are the Wilke-Chang equation and the Tynequation,given

关键词： diffusion coefficients infinite dilution group contribution method

A Spinor Approach to the SU(2) Clebsch-Gordan coefficients

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Communications in Theoretical Physics 2019年第6期71卷 663-669页

作者： Ling-Di Yang Fa-Min Chen Department of Physics Beijing Jiaotong University

We review the irreducible representation of an angular momentum vector operator constructed in terms of spinor algebra. We generalize the idea of spinor approach to study the coupling of the eigenstates of two independent angular momentum vector operators. Utilizing the spinor algebra, we are able to develop a simple way for calculating the SU(2) Clebsch-Gordan(CG) coefficients. The explicit expression for the SU(2) CG coefficients is worked out, and some simple physical examples are presented to illustrate the spinor approach.

关键词： Clebsch-Gordan coefficients spinors representations

Improved MPEG-4 High-Efficiency AAC With Variable-Length Soft-Decision Decoding of the Quantized Spectral coefficients

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China Communications 2019年第10期16卷 65-82页

作者： Sai Han Hongbing Ma Ping Zhang Tim Fingscheidt China United Network Communications Group Company Limited Beijing 100033China Beijing University of Posts and Telecommunications Beijing 100876China Institute for Communications Technology Technische Universitat BraunschweigBraunschweig 38106Germany

MPEG-4 High-Efficiency Advanced Audio Coding (HE-AAC) is designed for low bit rate applications, such as audio streaming in mobile communications. The HE-AAC audio codec offers a better coding efficiency since variable-length codes (VLCs) are adopted. However, HE-AAC has originally been designed for storage and error-free transmission conditions. For the transmission over bit error-prone channels, error propagation is a serious problem for the VLCs. Therefore, a robust HE-AAC decoder is desired, especially for mobile communications. In contrast to traditional hard-decision decoding, utilizing bit-wise channel reliability information, softdecision (SD) decoding has been known to offer better audio quality. In HE-AAC, the global gain parameter is coded with fixedlength codes (FLCs), while the scale factors and quantized spectral coefficients are coded with VLCs. In this work, we apply FL/SD decoding to the global gain parameter, VL/SD decoding to the parameters scale factors and quantized spectral coefficients. Especially, in order to apply VL/SD decoding to the quantized spectral coefficients, a new modified trellis representation in VL/SD decoding is proposed. An improved HE-AAC performance is clearly observed, with the support of both instrumental measurements and a subjective listening test.

关键词： variable-length soft-decision decoding HE-AAC trellis representation quantization spectral coefficients

L^p Solutions of BSDEs with a New Kind of Non-Lipschitz coefficients

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Acta Mathematicae Applicatae Sinica 2019年第4期35卷 695-707页

作者： Shengjun FAN Long JIANG School of Mathematics China University of Mining and Technology

In this paper, we are interested in solving multidimensional backward stochastic differential equations(BSDEs) with a new kind of non-Lipschitz coefficients. We establish an existence and uniqueness result of the L^p(... 详细信息

关键词： backward stochastic differential equation non-Lipschitz coefficients Mao’s condition Constantin’s condition Lp solution

Improvements in methodology to determine feedback reactivity coefficients

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Nuclear Science and Techniques 2019年第4期30卷 91-104页

作者： Faisal Qayyum Muhammad Rizwan Ali Awais Zahur R.Khan Department of Nuclear Engineering Pakistan Institute of Engineering and Applied Sciences (PIEAS) Department of Nuclear Engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)

The reactivity of a nuclear reactor is the most important safety and operating parameter. Due to short reactor period, the Light Water Reactor(LWR) designs require the compensations of rapid unfavorable reactivity increases. The increase in fuel or moderator temperature leads to compensate the reactivity jumps as inherent safety characteristics. The safe and reliable reactor operation requires the accurate assessment of these reactivity changes. This paper highlights the improvements in the methodology to determine the feedback reactivity changes in IAEA MTR benchmark. This method incorporates the reactivity effects of fuel temperature in moderator regions and vice versa. For this purpose, a detailed 3D model of the IAEA 10 MW MTR benchmark reactor is developed employing OpenMC computer code. OpenMC is a probabilistic computer code for neutronic calculations. This work uses temperature-dependent JEFF 3.2 cross-sectional library. The model is validated against the reference results of eigenvalues for control rods(inserted and in fully withdrawn position), control rod reactivity worth, averaged thermal flux in the central flux trap, and power fraction for each fuel element at beginning of life. The validated model is applied to simulate the feedback reactivity coefficients against the conventional reference results. In order to improve the methodology, the effect of the moderator temperature and void on fuel is incorporated to obtain a more realistic value of the fuel temperature ***, the moderator temperature coefficient and void coefficient are improved by incorporating the coupling effects of fuel temperature on moderator. This methodology can be applied to improve the LWR designs.

关键词： OpenMC MTR benchmark Reactivity feedback coefficients Fuel temperature coefficient Moderator temperature coefficient Void coefficient of reactivity