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Preparation of Low Ratio Magnesium Ccement by Acid Leaching Treatment of Boron Mud

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 120-129页

作者：杨梅 ZHANG Mingzhe chen hao School of Materials Science and Engineering Shenyang Jianzhu University School of Physical Science and Technology Shenyang Normal University

The effects of liquid-solid ratio and reaction time on the leaching rate of magnesium at room temperature were investigated,as well as the effects of the molar ratio of MgO/MgCl2,the amount of water added,and the amount of acid-impregnated slag dosed on the compressive strength and water resistance of *** results showed that the magnesium element in the boron mud could be maximally leached under the conditions of 1:1 concentration of hydrochloric acid at room temperature,liquid-solid ratio of 2.5 mL·g-1,and reaction time of 5 h,and the main products were amorphous SiO2as well as a small amount of magnesium olivine which had not been completely *** LR-MOC prepared using the acid-soaked mixture could reach a softening coefficient of 0.85 for 28 d of water immersion when the molar ratio of MgO/MgCl2was 2.2,the amount of water added was 0 g,and the acid-soaked slag dosing was 40 wt%,which also led to an appreciable late-strength,with an increase of 19.4% in compressive strength at 28 d compared to that at 7 *** previous studies,LR-MOC prepared in this way has a final strength phase that is not the more easily hydrolysed 3-phase but the lath-like *** this phenomenon,we analyzed the mechanism and found that,during the acid leaching process,a part of amorphous SiO2dissolved in the acid leaching solution formed a silica sol,in which Mg2+played a bridging role to make the silica sol more *** the addition and hydrolysis of MgO,the silica sol gel coagulation slows down,providing a capping layer to inhibit the hydrolysis of the 5-phase crystals and providing some strength after *** amorphous SiO2in the other part of the acid-impregnated slag generated M-S-H gel with Mg2+and OH-,which synergised with the dense structure composed of interlocking crystals to improve the water resistance of LR-MOC.

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Experimental study of a novel heat sink for distribution level static synchronous compensator cooling

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Science China(Technological Sciences) 2020年第9期63卷 1764-1775页

作者： chen hao LI Qiang MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EingineringNanjing University of Sciene&TechnologyNanjing 210094China

In this paper, a novel heat sink which coupling natural convection and phase transition was designed to meet the cooling requirements of distribution level static synchronous compensator(DSTATCOM). The two inclined evaporation substrates can meet the requirements for the parallel operation of DSTATCOM and the working medium R245 fa was driven by gravity and buoyancy in the heat sink. The influence of filling ratio and heating power on the thermal performance of the heat sink was investigated experimentally and theoretically. The experimental results showed that the filling ratio and heating power had a significant influence on the thermal performance of the heat sink. At the ambient temperature of 25℃, the heat sink could start up successfully at different heating power and filling ratio. Meanwhile, the heat sink achieved good heat dissipation performance as the maximum temperature of two evaporation substrates were 60.14℃ and 67.85℃ while the heating power was 3000 Wand the filling ratio was 80%. The heat transfer resistance between two evaporation substrates and condensation substrates were6.6×10^-3℃/W and 1.2×10^-2℃/W at the same working condition. Additionally, the experimental results showed a good agreement with the calculated results.

关键词： natural convection phase transition thermal performance maximum temperature heat transfer resistance

On Optical Polarons in One Dimensional Molecular-Crystal Chains

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Chinese Physics Letters 1996年第8期13卷 617-620页

作者： chen hao chen Yuan Department of Physics South China Normal UniversityGuangzhou 510631

An improved solution for the optical polarons in the molecular-crystal model with the dispersion term in one dimensional chains is *** approximation neglecting the dispersion term,the improved solution tends to usual ... 详细信息

关键词： solution dispersion polaron

Relationship between contact size and static friction:An approach for rigid crystalline surfaces

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Friction 2021年第3期9卷 502-512页

作者： hao chen Xinlei GAO School of Chemical and Environmental Engineering Wuhan Polytechnic UniversityWuhan 430023China

Relationship between contact size(A)and static friction(f)has been studied for rigid crystalline *** built a series of systems with two identical surfaces but different orientations and investigated the effects of the size and shape of the contact area on static *** these systems,there are numerous nontrivial commensurate *** results confirmed that the relationship between A and f was determined by both commensurability and shape of the *** commensurate contacts,f∝A independent of the *** incommensurate contacts,generally f∝A^(0) for regular shapes or f∝A^(1/4) for irregular shapes;however,in very few cases of regular shapes,f∝A^(1/2).Moreover,in above systems,commensurability of a contact can be easily changed by a perturbation of the misfit ***,if the perturbation caused by the lateral force and the deformation of the surface are considered(as is the case in real systems),further research is necessary.

关键词： static friction contact size numeric simulation rigid body

Fast algorithms for determining the linear complexities of sequences over GF(p^(m)）with the period 3n

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Science China Mathematics 2006年第5期49卷 715-720页

作者： chen hao Department of Computing and Information Technology Fudan University Shanghai 200433 China

In this paper, for the the primes p such that 3 is a divisor of p - 1, we prove a result which reduces the computation of the linear complexity of a sequence over GF(pm)(any positive integer m) with the period 3n (n and pm - 1 are coprime) to the computation of the linear complexities of three sequences with the period n. Combined with some known algorithms such as generalized Games-Chan algorithm, Berlekamp-Massey algorithm and Xiao-Wei-Lam-lmamura algorithm, we can determine the linear complexity of any sequence over GF(pm) with the period 3n (n and pm - 1 are coprime) more efficiently.

关键词： number theory of the finite field, cryptography, stream cipher, fast algorithm.

Restricted parameter range promise set cover problems are easy

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Frontiers of Mathematics in China 2014年第6期9卷 1253-1260页

作者： hao chen Department of Mathematics Hangzhou Dianzi University Hangzhou 310018 China

The restricted parameter range set cover problem is a weak form of the NP-hard set cover problem with the restricted range of parameters. We give a polynomial time algorithm for this problem by lattices.

关键词： Set cover problem lattice closest vector problem (CVP) shortestvector problem (SVP)

Thermal design of a novel heat sink cooled by natural convection with phase transition in the series loop

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Science China(Technological Sciences) 2018年第11期61卷 1732-1744页

作者： chen hao LI Qiang MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power Engineering Nanjing University of Science & Technology

In this paper, a novel heat sink, cooled by natural convection, with phase transition in the circulation loop was designed, and the heat sink was applied on averaging temperature and cooling the electronic equipment. The working fluid in the heat sink was driven by the capillary pump. Numerical simulations were performed, to study the heat transfer performance of two systems with various heating power, filling ratios and refrigerants. The influences of above elements on temperature uniformity of two systems were also studied and the thermal performances of two systems were compared. The volume of fluid(VOF) model was utilized to simulate fluid motion in ANSYS FLUENT. The simulation results indicate that the temperature differences of the system comprising two substrates(system 1) are very small under suitable filling ratio conditions, and the thermal performance of system 1 is preferable to the system comprising one substrate(system 2) at the same volume. Besides, the simulation results also show that the system using R245 fa possesses excellent temperature uniformity for the same filling ratio and heating ***, the experiments were investigated and the experimental results proved the correctness of the theoretical model.

关键词： natural convection vapor chamber circulation loop filling ratio temperature difference

SOME SEMI-BENT FUNCTIONS WITH POLYNOMIAL TRACE FORM

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Journal of Systems Science & Complexity 2014年第4期27卷 777-784页

作者： chen hao CAO Xiwang Department of Math Nanjing University of Aeronautics and Aeronautics

This paper is devoted to the study of semi-bent functions with several parameters flexible on the finite field *** functions defined on F2n of the form f（r）ab（x） =Trn1（axr（2m-1））＋Tr41（bx（2n-1）/5） and the form g（rs）abcd（x）=Trn1（axr（2m-1））＋Tr41（bx（2n-1）/5）＋Trn1（cx（2m-1）1/2＋1）＋Trn1（dx（2m-1）s＋1） where n = 2m,m = 2（mod 4）,a,c ∈ F2n,and b ∈ F（16）,d ∈ F2,are investigated in constructing new classes of semi-bent *** characteristic sums such as Kloosterman sums and Weil sums are employed to determine whether the above functions are semi-bent or not.

关键词： Boolean function Dickson polynomial exponential sum Kloosterman sum semi-bentfunction Walsh-Hadamard transformation Weil sum.

Hash signature saving in distributed video coding

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 163-170页

作者： Xin-hao chen Institute of Information and Communication Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Key Laboratory of Information Network Technology Hangzhou 310027 China

In transform-domain distributed video coding (DVC), the correlation noises (denoted as N) between the source block and its temporal predictor can be modeled as Laplacian random variables. In this paper we propose that the noises (denoted as N′) between the source block and its co-located block in a reference frame can also be modeled as Laplacian random variables. Furthermore, it is possible to exploit the relationship between N and N′ to improve the performance of the DVC system. A practical scheme based on theoretical insights, the hash signature saving scheme, is proposed. Experimental results show that the proposed scheme saves on average 83.2% of hash signatures, 13.3% of bit-rate, and 3.9% of encoding time.

关键词： Distributed video coding (DVC) Hash Laplacian