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Dependence of Amorphous Formation Ability on Intrinsic Parameters in Dy-Gd-Co-Al Alloys

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Journal of Materials Science & Technology 2009年第5期25卷 665-668页

作者： Lin Luo rui tian Xueshan Xiao Institute of Materials Shanghai University Shanghai 200072 China

A series of Dy（Gd）-based bulk amorphous alloy rods were prepared by water-cooled copper mold method. Thermal stability and structure of Dy-Gd-Co-Al alloys were investigated by differential scanning calorimetry and X-ray diffraction, respectively. The results show that the Dy-Gd-Co-Al alloys have good glass-formation ability, and the Dy31Gd25Co20Al24 alloy can be readily cast into full glassy rods up to 5 mm in diameter. The glass-forming ability of multicomponent alloys was greatly dependent on their chemical interaction and the equivalent bond parameters among atoms such as equivalent electronegativity difference, equivalent atomic size parameter. The Dy （Gd）-based bulk amorphous alloys could be expected as potential functional materials.

关键词： Dy(Gd)-based Glass forming ability Intrinsic parameters

Effect of Impeller Solidity on the Generating Performance for Solar Power Generation

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Journal of Electronic Science and Technology 2021年第4期19卷 308-318页

作者： Jia Liu rui tian Jing Nie with the College of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot 010051 with the College of Aeronautics Inner Mongolia University of TechnologyHohhot 010051

According to current solar power research,both the generating unit’s minimum start-up speed and power generation system’s minimum flow rate for operation decrease with the increase in the impeller ***,a high solidity should be achieved,as this translates more power for a solar power system in the start-up and shut-down ***,increasing the number of blades does not increase the impeller solidity;therefore,there is an optimal number of blades needed to achieve the preferred *** paper begins by selecting the blade airfoil and then performs a theoretical analysis based on the relationship between the blade number and chord *** are conducted to measure the starting and stopping wind speeds and power characteristics for different numbers of *** results show that a maximum impeller solidity of 0.2862 is achieved,as well as the minimum flow speed at the start-up,and the maintenance of the solar chimney power generation system is optimized when there are four blades.

关键词： Blade number impeller solidity solar chimney power generation

Nonlinear Time Series Prediction Using LS-SVM with Chaotic Mutation Evolutionary Programming for Parameter Optimization

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Communications in Theoretical Physics 2006年第4期45卷 641-646页

作者： XU rui-rui CHEN tian-Lun GAO Cheng-Feng Department of Physics Nankai University Tianjin 300071 China

Nonlinear time series prediction is studied by using an improved least squares support vector machine （LSSVM） regression based on chaotic mutation evolutionary programming （CMEP） approach for parameter optimization. We analyze how the prediction error varies with different parameters （σ, γ） in LS-SVM. In order to select appropriate parameters for the prediction model, we employ CMEP algorithm. Finally, Nasdaq stock data are predicted by using this LS-SVM regression based on CMEP, and satisfactory results are obtained.

关键词： nonlinear time series prediction least squares support vector machine chaotic mutation evolu tionary programming

Stereoselective Total Synthesis of Tubulysin V

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Chinese Journal of Chemistry 2013年第1期31卷 40-48页

作者： rui Wang Ping tian Guoqiang Lin CAS Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

The total synthesis of tubulysin V was accomplished in 1.0% overall yield with linear 13 steps. Our synthetic strategy featured the following two reactions. One is zinc-mediated aza-Barbier reaction of （R）-N-tert-butane- sulfinyl imine 8 with β-ester group functionalized allylic bromide 9 to afford the chiral homo-allylic amine （7）; the other is to employ the methodology of aqueous indium-mediated aza-Barbier reaction previously developed by our group, giving the chiral homo-allylic amine 13 with high efficiency.

关键词： tubulysin V N-tert-butanesulfinyl imines zinc indium aza-Barbier reaction

Observation of specific ion effects in humus aggregation process

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Pedosphere 2021年第5期31卷 736-745页

作者： rui tian Xinmin LIU Xiaodan GAO rui LI Hang LI Chongqing Key Laboratory of Soil Multi-scale Interfacial Process College of Resources and EnvironmentSouthwest UniversityChongqing 400715(China)

Specific ion effects play a vital role in a variety of colloidal and interfacial ***,few studies have reported the specific ion effects in the humus aggregation process,which strongly influence the transport and fate of environmental *** this study,soil humus colloids were prepared and characterized,and the specific ion effects on humus aggregation in electrolyte solutions were investigated at a variety of concentrations and pH values using dynamic light scattering *** energy(ΔE),which is known to reflect the dynamics and stability of a colloidal system,was used to quantitatively characterize the specific ion *** results showed that given ΔE value of 2.48×10^(3) J mol^(-1) at pH 3.0,the electrolyte concentrations were 91.6,58.2,3.8,and 0.8 mmol L^(-1) for Na^(+),K^(+),Mg^(2+),and Ca_(2+),respectively,thus indicating significant specific ion effects in the humus aggregation *** importantly,decreasing the electrolyte concentrations increased the differences in the ΔE value between two cation species with the same valence(i.e.,ΔE_(Na)-ΔE_(K) and ΔE_(Mg)-ΔE_(Ca)),while increasing the pH increased the magnitude of ΔE_(Mg)-ΔE_(Ca).However,the classic Derjaguin,Landau,Verwey,and Overbeek(DLVO)theory and the double layer theory,as well as the currently widely used ionic hydration and dispersion effects,failed to predict the experimentally observed increase in the specific ion effects with decreasing electrolyte concentrations in a quantitative *** results have implications for the necessity of involving specific ion effects for a better understanding of humus aggregation and interactions in aqueous and soil systems.

关键词： Derjaguin Landau Verwey and Overbeek theory double layer theory ionic dispersion ionic hydration supramolecular aggregates

Specific ion effect of H^(+) on variably charged soil colloid aggregation

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Pedosphere 2020年第6期30卷 844-852页

作者： Yekun ZHANG rui tian Jia TANG Hang LI Chongqing Key Laboratory of Soil Multi-Scale Interfacial Process College of Resources and EnvironmentSouthwest UniversityChongqing 400715China

Specific ion effects(Hofmeister effects)have recently attracted the attention of soil scientists,and it has been found that ionic non-classic polarization plays an important role in the specific ion effect in ***,this explanation cannot be applied to H+.The aim of this work was to characterize the specific ion effect of H+on variably charged soil(yellow soil)colloid *** total average aggregation(TAA)rate,critical coagulation concentration(CCC),activation energy,and zeta potential were used to characterize and compare the specific ion effects of H+,K+,and Na+.Results showed that strong specific ion effects of H+,K+,and Na+existed in variably charged soil colloid *** TAA rate,CCC,and activation energy were sensitive to H+,and the addition of a small amount of H+changed the TAA rate,CCC,and activation energy *** zeta potential results indicated that the specific ion effects of H+,K+,and Na+on soil colloid aggregation were caused by the specific ion effects of H+,K+,and Na+on the soil electric field *** addition,the origin of the specific ion effect for H+was its chemical adsorption onto surfaces,while those for alkali cations were non-classic *** study indicated that H+,which occurs naturally in variably charged soils,will dominate variably charged soil colloid aggregation.

关键词： activation energy chemical adsorption critical coagulation concentration dynamic light scattering Hofmeister effect total average aggregation rate zeta potential

The big bang of genome editing technology: development and application of the CRISPR/Cas9 system in disease animal models

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Zoological Research 2016年第4期37卷 191-204页

作者： Ming SHAO tian-rui XU Ce-Shi CHEN Faculty of Life Science and Technology Kunming University of Science and Technology Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and Yunnan Province Kunming Institute of Zoology Chinese Academy of Sciences

Targeted genome editing technology has been widely used in biomedical studies. The CRISPR- associated RNA-guided endonuclease Cas9 has become a versatile genome editing tool. The CRISPR/Cas9 system is useful for studying gene function through efficient knock-out, knock-in or chromatin modification of the targeted gene loci in various cell types and organisms. It can be applied in a number of fields, such as genetic breeding, disease treatment and gene functional investigation In this review, we introduce the most recent developments and applications, the challenges, and future directions of Cas9 in generating disease animal model. Derived from the CRISPR adaptive immune system of bacteria, the development trend of Cas9 will inevitably fuel the vital applications from basic research to biotechnology and bio- medicine.

关键词： CRISPR/Cas9 Animal models Genetherapy

A simple calculation model for thermodynamic equilibrium information between precipitation and matrix

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Journal of Iron and Steel Research International 2018年第11期25卷 1156-1162页

作者： Yong Yang tian-rui Li Tao Jia Zhao-dong Wang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

A simple theoretical model was developed to predict equilibrium between precipitate and matrix in a multicomponent microalloyed *** solute concentration in the matrix,the composition and the volume fraction of the precipitated second phases,and the reduction in critical precipitation temperature of AlN induced by carbonitride were quantified by the proposed thermodynamic *** results predicted by the developed model and those by other approaches are in a good *** main advantages of this model over the existing models are that the process of formulation derivation is simple and the model can be easily solved by a personal program.

关键词： AlN precipitation Carbonitride Thermodynamic model Phase equilibrium

Unraveling the size distributions of surface properties for purple soil and yellow soil

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Journal of Environmental Sciences 2015年第6期27卷 81-89页

作者： Ying Tang Hang Li Xinmin Liu Hualing Zhu rui tian Chongqing Key Laboratory of Soil Multi-Scale Interfacial Process College of Resources and Environment Southwest University Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Soils contain diverse colloidal particles whose properties are pertinent to ecological and human health, whereas few investigations systematically analyze the surface properties of these particles. The objective of this study was to elucidate the surface properties of particles within targeted size ranges（i.e. 〉 10, 1-10, 0.5-1, 0.2-0.5 and 〈 0.2 μm） for a purple soil（Entisol） and a yellow soil（Ultisol） using the combined determination method. The mineralogy of corresponding particle-size fractions was determined by X-ray *** found that up to 80% of the specific surface area and 85% of the surface charge of the entire soil came from colloidal-sized particles（〈 1 μm）, and almost half of the specific surface area and surface charge came from the smallest particles（〈 0.2 μm）. Vermiculite,illite, montmorillonite and mica dominated in the colloidal-sized particles, of which the smallest particles had the highest proportion of vermiculite and montmorillonite. For a given size fraction, the purple soil had a larger specific surface area, stronger electrostatic field, and higher surface charge than the yellow soil due to differences in ***, the differences in surface properties among the various particle-size fractions can also be ascribed to mineralogy. Our results indicated that soil surface properties were essentially determined by the colloidal-sized particles, and the 〈 0.2 μm nanoparticles made the largest contribution to soil properties. The composition of clay minerals within the diverse particle-size fractions could fully explain the size distributions of surface properties.

关键词： Particle size distribution Soil colloids Surface charge number Specific surface area Clay minerals