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Vibrational Resonance in Fractional-Order Anharmonic Oscillators

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Chinese Physics Letters 2012年第10期29卷 97-100页

作者： YANG jian-hua School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116

The phenomenon of vibrational resonance in fractional-order anharmonic oscillators is *** on the method of separating slow and fast motions,the approximate solution of the response amplitude is *** analytical and numerical results show that not only the high-frequency signal but also the fractional-order damping can induce vibrational *** present results provide a new way to control periodical signals in coupled systems.

关键词： harmonic vibrational fractional

New Active Organic Substance in Oyster Shell Capable of Scavenging Oxygen Free Radicals with High Efficiency

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Chemical Research in Chinese Universities 2008年第2期24卷 171-174页

作者： MA jian-hua College of Biology Engineering Jimei University Xiamen 361021 P. R. China

A light purple organic active substance capable of scavenging hydroxyl radical（OH） with a high efficiency was extracted from Oyster shell at an extraction rate of 2.49%. It was found for the first time that this active substance may scavenge OH with the efficiency far higher than that of vitamin C. This active substance may scavenge also superoxide radical（O2） although the scavenging efficiency is far lower than that of vitamin C. Infrared spectrometry and routine chemical analysis primarily reveal that this active substance belongs to glycoprotein.

关键词： Oyster shell Glycoprotein Scavenging Hydroxyl radical Superoxide radical

Mn evaporation and denitrification behaviors of molten Mn steel in the vacuum refining with slag process

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1288-1297页

作者： jian-hua Chu Yan-ping Bao State Key Lab of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Considering the precise composition control on the vacuum refining of high-Mn steel, the behaviors of both Mn evaporation and nitrogen removal from molten Mn steel were investigated via vacuum slag refining in a vacuum induction furnace. It was found that the reaction interfaces of denitrification and Mn evaporation tend to migrate from the surface of slag layer to the surface of molten steel with the gradual exposure of molten steel during the vacuum slag refining process. Significantly, compared with the experimental group without slag addition, the addition of slag into steel can result in a lower Mn evaporation rate constant of 0.0192 cm·min~(-1) at 370 Pa, while the denitrification rate is almost not affected. Besides, the slag has a stronger inhibitory effect on Mn evaporation than the reduced vacuum pressure. Moreover, the inhibitory effect of the slag layer on Mn evaporation can be weakened with the increase of the initial Mn content in molten steel. The slag layer can work as an inhibitory layer to reduce the Mn evaporation from molten steel, the evaporation reaction of Mn mainly proceeds on the surface of the molten steel. This may be attributed to the Mn mass transfer coefficient for one of reaction at steel/slag interface, mass transfer in molten slag, and evaporation reaction at slag/gas interface is lower than that of evaporation reaction at steel/gas interface. The introduction of slag is proposed for both denitrification and manganese control during the vacuum refining process of Mn steels.

关键词： manganese evaporation denitrification vacuum slag evaporation rate

Asymmetric Synthesis and Crystal Structure of a Bioactive Morpholine Derivative

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Chinese Journal of Structural Chemistry 2007年第5期26卷 515-518页

作者： WANG jian-Ping FU Yong-Ju WANG jian-Ge QIN jian-hua CHEN Qing-hua Department of Chemistry Luoyang Normal University Luoyang 471022China Chemical Engineering ＆ Pharmaceutics College Henan Universityof Science and Technology Luoyang 471003 China

A novel morpholine derivative was synthesized by Michael addition/internal nucleophilic substitution of 4-（L）-menthyloxy（1R,2S,5R）-butenolide with phenyl-glyalcohol under mild condition, and its structure was determined by X-ray diffraction. The target compound belongs to orthorhombic, space group P212121 with a = 5.7729（7）, b = 11.5032（14）, c = 25.161（3）A, Mr = 319.35, Z = 4, V = 1670.8（4）A^3, Dc = 1.270 g/cm3, μ（MoKα） = 0.094 mm^-1, F（000） = 680, Flack = 0.01（2）, R = 0.0398 and wR = 0.0914.

关键词： morpholine derivative α-phenyl-glyalcohol,4-(L)-menthyloxy-butenolide asymmetric synthesis

FLOW REGIMES BELOW AERATORS FOR DISCHARGE TUNNELS

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Journal of Hydrodynamics 2012年第3期24卷 378-382页

作者： MA Fei WU jian-hua College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

The flow regimes below an aerator influence directly the air entrainment and the cavitation damage control. Based on the theoretical considerations, the experiments of the aerator for a discharge tunnel were conducted, and the relationships between the flow regime and hydraulic and geometric parameters were investigated. The results showed that, there are two kinds of threshold values for the flow regime conversions. One is Fr1-2 standing for the conversion from the fully filled cavity to the partially filled cavity, and the other is Fr2-3 which shows the change from the partially filled cavity to the net air cavity. Two empirical expressions were obtained for the conversions of the flow regimes, which can be used in the designs of the aerators.

关键词： aerator discharge tunnel flow regime filling water jet length

Denaturation behavior of inclusions in industrial pure iron by calcium treatment

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Journal of Iron and Steel Research International 2023年第2期30卷 249-258页

作者： Xin Liu Yan-ping Bao Cheng-jian hua jian-hua Chu Chao Gu Min Wang State Key Lab of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

Only a few Chinese enterprises can produce high-quality industrial pure iron,and studies on the smelting process of industrial pure iron were *** inclusions in a melting process were characterized by means of electron microscopy and an automatic inclusion analysis system,and the evolution mechanism of inclusion was studied using thermodynamic calculation to optimize the calcium alloy addition in liquid *** results show that during the smelting process,inclusions mainly composed of Al_(2)O_(3)and spinel are formed before calcium *** calcium treatment,they continuously react with[Ca],[S]and[Ti],grow up,and are removed during refining and tundish *** the end,there are more small-sized inclusions containing CaS,and the contents of Al_(2)O_(3)and spinel are *** to thermodynamic calculations,the appropriate calcium treatment liquid window for the molten steel composition is(10-38)×10^(-6).Calcium treatment has changed the main types of inclusions in industrial pure iron from Al_(2)O_(3)to small-sized inclusions containing CaS and effectively reduces the influence of Al_(2)O_(3)inclusions on the quality of industrial pure iron.

关键词： Industrial pure iron Calcium treatment Inclusion Thermodynamic CaS

Transient stochastic response of quasi integerable Hamiltonian systems

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Acta Mechanica Sinica 2013年第4期29卷 602-611页

作者： Zhong-hua Liu jian-hua Geng Wei-Qiu Zhu Department of Civil Engineering Xiamen University Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

The approximate transient response of quasi in- tegrable Hamiltonian systems under Gaussian white noise excitations is investigated. First, the averaged It6 equa- tions for independent motion integrals and the associated Fokker-Planck-Kolmogorov （FPK） equation governing the transient probability density of independent motion integrals of the system are derived by applying the stochastic averag- ing method for quasi integrable Hamiltonian systems. Then, approximate solution of the transient probability density of independent motion integrals is obtained by applying the Galerkin method to solve the FPK equation. The approxi- mate transient solution is expressed as a series in terms of properly selected base functions with time-dependent coeffi- cients. The transient probability densities of displacements and velocities can be derived from that of independent mo- tion integrals. Three examples are given to illustrate the ap- plication of the proposed procedure. It is shown that the re- suits for the three examples obtained by using the proposed procedure agree well with those from Monte Carlo simula- tion of the original systems.

关键词： Transient response ~ Stochastic averagingmethod ~ Galerkin method ~ Quasi integrable Hamiltoniansystem

S空位及非金属掺杂单层Bi_(2)S_(2)Se的第一性原理研究

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原子与分子物理学报 2025年第1期42卷 127-134页

作者：张建华王敏陈畅曹倩徐银湖北大学资源环境学院武汉430062

Bi_(2)S_(2)Se是一种新兴的具有优异光电性能的材料,因此受到了广泛的关注.本研究采用第一性原理方法和开源程序,研究了本征单层Bi_(2)S_(2)Se以及掺杂非金属元素X(X=P,Cl,Br和I)和S空位的体系的电子结构和光学特性.计算结果表明,改性... 详细信息

Bi_(2)S_(2)Se是一种新兴的具有优异光电性能的材料,因此受到了广泛的关注.本研究采用第一性原理方法和开源程序,研究了本征单层Bi_(2)S_(2)Se以及掺杂非金属元素X(X=P,Cl,Br和I)和S空位的体系的电子结构和光学特性.计算结果表明,改性后出现了晶格缺陷.含S空位和P、Cl、Br掺杂体系的带隙减少,而I掺杂体系的带隙增加.同时,含S空位和Cl、Br、I掺杂体系的费米能级穿过导带底,而P掺杂体系的费米能级穿过价带顶.所有改性体系在费米能级附近都出现了缺陷能级或杂质能级,表现出较高的可见光吸收能力和散射能力,改性体系的对可见光的吸收能力和散射能力有所增加.

关键词： Bi_(2)S_(2)Se 掺杂电子结构光学性质第一性原理

Determination of liquidus temperatures in high-alloyed Fe-C-Mn-Si- Al steels using differential thermal analysis

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Journal of Iron and Steel Research International 2018年第5期25卷 546-553页

作者： Chang-ling Zhuang jian-hua Liu College of Materials and Metallurgy Guizhou UniversityGuiyang 550025 Guizhou China Engineering Research Institute University of Science andTechnology Beijing Beijing 100083 China

The liquidus temperature of the Fe-C-Mn-Si-Al alloy was investigated by using an improved differential thermal analysis method, which effectively tackles down the manganese evaporation in the course of differential thermal analysis experiments for high-manganese twinning-induced plasticity （TWIP） steels at high temperature. It was found that the liquidus temperature is more strongly dependent on the silicon content than expected. By considering the high manganese content in the Fe-C-Mn-Si-Al TWIP steels, the effect of carbon content on the depression coefficient of manganese should not be ignored, which has considerable impact on the liquidus temperature. An equation was summarized to effectively predict the liquidus temperature for a wide range of high-manganese steels. Meanwhile, the prediction results of the equation are consistent with the experimental results, as well as those results acquired from ThermoCalc.

关键词： TWIP steel Thermal analysis Liquidus temperature High-manganese steel