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A Remark on З-Permutability of Finite Groups

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Acta Mathematica Sinica,English Series 2007年第11期23卷 1985-1990页

作者： Li Fang wang School of Mathematics Zhongshan University Guangzhou 510275 P. R. China Department of Mathematics Shanxi Teachers University Linfen 041004 P. R. China Lingnan College and School of Mathematics Zhongshan University Guangzhou 510275 P. R. China Department of Mathematics Nanchang University Nanchang 330047 P. R. China

Let З be a complete set of Sylow subgroups of a finite group G, that is, З contains exactly one and only one Sylow p-subgroup of G for each prime p. A subgroup of a finite group G is said to be З-permutable if it permutes with every member of З. Recently, using the Classification of Finite Simple Groups, Heliel, Li and Li proved tile following result： If the cyclic subgroups of prime order or order 4 iif p = 2） of every member of З are З-permutable subgroups in G, then G is supersolvable.In this paper, we give an elementary proof of this theorem and generalize it in terms of formation.

关键词： З-permutable subgroups supersolvable groups saturated formations

Huge permittivity and premature metallicity in Bi2O2Se single crystals

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Science China(Physics,Mechanics & Astronomy) 2021年第6期64卷 90-97页

作者： ZhuoKai Xu JiaLu wang Tao wang wangHua Hu XiaoHui Yang Xiao Lin Deparment of Physics Zhejiang UniversiyHangzhou 310027China Key Laboratory for Quantum Materials of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Instiute for Advanced StudyHangzhou 310024China

Bi_(2)O_(2) Se is a promising material for next-generation semiconducting *** exhibits premature metallicity on the introduction of a tiny amount of electrons,the physics behind which remains *** we report on transport and dielectric measurements in Bi_(2)O_(2) Se single crystals at various carrier *** temperature-dependent resistivity(p)indicates a smooth evolution from the semiconducting to the metallic *** critical concentration for the metal-insulator transition(MIT)to occur is extraordinarily low(nc~10^(16) cm^(-3)).The relative permittivity of the insulating sample is huge(∈r≈155(10))and varies slowly with *** with the light effective mass,a long effective Bohr radius(a_(B)^(*)≈36(2)nm)is derived,which provides a reasonable interpretation of the metallic prematurity according to Mott’s criterion for *** high electron mobility(μ)at low temperatures may result from the screening of ionized scattering centers due to the huge∈*** findings shed light on the electron dynamics in two dimensional(2D)Bi_(2)O_(2) Se devices.

关键词： next-generation semiconductor Bi_(2)O_(2)Se metal-insulator transition premature metallicity huge permittivity Mott’s criterion

Scallop ice shape characteristics of swept wing based on large-scale icing wind tunnel experiment

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Chinese Journal of Aeronautics 2023年第12期36卷 214-230页

作者： Qiang wang Ningli CHEN Yuanbo wang Weihao LI Yu LIU Xian YI Low Speed Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China Anti/de-icing Key Laboratory of China Aerodynamics Research and Development Center Mianyang 621000China Key Laboratory of Aerodynamics Mianyang 621000China Design and Research Institute of AVIC Shaanxi Aircraft Industry Group Hanzhong 723000China

Scallop ice is a special phenomenon that occurs during swept wing aircraft passing through icing *** poses a great challenge for the icing safety assessment that the complex scallop ice shape feature and its mechanism are still *** this work,a large-scale icing wind tunnel experiment of swept wing designed by NACA0012 airfoil is conducted in the Icing Wind Tunnel of China Aerodynamics Research and Development *** detailed three-dimensional ice shapes under 0°,15°,30°and 45°swept angles are obtained by laser scanning *** experimental results show that with the swept angle increasing from 0°to 45°,the 2D double ice horn structures show certain spanwise variation,and finally transform into complete scallop ice with ice thickness greatly enhanced in the stagnation line *** empirical mode decomposition of the spanwise ice curve captures the high-frequency fluctuation on the scallop ice caused by the small-scale roughness element,while the trend with low frequency is not *** on the experimental data,a new complete scallop ice geometric model,named 5Points-5Lines-2Arcs(5P-5L-2A)model,is proposed,which can provide important basis for the quantitative description of complex scallop ice shape.

关键词： Aircraft Swept wings Scallop ice Icing wind tunnel experi-ment Scallop ice geometric model

Enhanced extraction of essential oil from Cinnamomum cassia bark by ultrasound assisted hydrodistillation

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Chinese Journal of Chemical Engineering 2021年第8期34卷 38-46页

作者： Guanghui Chen Fengrui Sun Shougui wang Weiwen wang Jipeng Dong Fei Gao Key Laboratory of Mutiphase Flow Reaction and Separation Engineering of Shandong Province College of Chemical EngineeringQingdao University of Science and TechnologyQingdao 266042China Fundamental Chemistry Experiment Center(Gaomi) Qingdao University of Science and TechnologyGaomi 261500China

Cinnamon essential oil with many bioactivities is an important raw material for the production of various chemicals,and the conventional hydrodistillation(HD)for cinnamon oil extraction always require a longer extraction *** this work,ultrasound-assisted hydrodistillation extraction(UAHDE)technique was employed to enhance the extraction efficiency of essential oils from cinnamon *** parameters with significant effects on the essential oil extraction efficiency(ultrasound time,ultrasound power,extraction time,liquid–solid ratio)were optimized,and the proposed UAHDE was compared with the conventional HD extraction in terms of the extraction time,extraction yield,and physicochemical properties of extracted *** to the HD extraction,the UAHDE resulted in a shorter extraction time and a higher extraction *** GC–MS analysis,the UAHDE provided more valuable essential oil with a high content of the vital trans-cinnamaldehyde compounds compared with the *** electron micrograph(SEM)confirmed the efficiency of ultrasound irradiation for cinnamon oil *** addition,the analysis of electric consumption and CO_(2) emission shows that the UAHDE process is a more economic and environment-friendly ***,UAHDE is an efficient and green technology for the cinnamon essential oil extraction,which could improve the quantity and quality of cinnamon oils.

关键词： Cinnamon oil Extraction Ultrasound Distillation Optimization Chemical composition

Numerical Investigation of Flow and Heat Transfer in Vane Impingement/Effusion Cooling with Various Rib/Dimple Structure

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Journal of Thermal Science 2023年第4期32卷 1357-1377页

作者： wang Mingrui ZHU Huiren LIU Cunliang wang Rui WU Zhuang YAO Chunyi School of Power and Energy Northwestern Polytechnical UniversityXi’an710129China

By investigating heat transfer and flow structures of dimples,orthogonal ribs,and V-shaped ribs in the impingement/effusion cooling,the article is dedicated to selecting a best-performing internal cooling structure for a turbine *** overall cooling effectiveness and coolant consumption are adopted to evaluate the cooling *** analyze the influence of structural modification,the flow field is investigated on chordwise/spanwise sections and the target *** blockage effect on crossflow can protect jet flow,resulting in higher heat transfer performance of the target *** own a stronger blockage effect than *** with the blockage effect,the influence of the rib shape is *** installing dimples between ribs,heat transfer is augmented *** introduction of ribs/dimples leads to higher discharge coefficients of jet nozzles but lower discharge coefficients of film ***,the film cooling ***,the installation of the ribs and dimples decreases total coolant *** effect of ribs/dimples on heat transfer and effusion condition of internal and external cooling is *** best-performing cooling structure is the target surface with dimples and orthogonal ribs,which decreases the wall temperature and coolant consumption by 14.57-28.03 K and 1.19%-1.81%*** article concludes the flow mechanism for dimples and influence factors on the cooling performance,which may serve as guidance for the turbine vane design.

关键词： conjugate heat transfer impingement cooling dimple V-shape rib discharge coefficient

In silico prediction methods of self-interacting proteins:an empirical and academic survey

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Frontiers of Computer Science 2023年第3期17卷 199-216页

作者： Zhanheng CHEN Zhuhong YOU Qinhu ZHANG Zhenhao GUO Siguo wang Yanbin wang College of Computer Science and Software Engineering Shenzhen UniversityShenzhen 518060China School of Computer Science Northwestern Polytechnical UniversityXi’an 710129China Institute of Machine Learning and Systems Biology School of Electronics and Information EngineeringTongji UniversityShanghai 201804China School of Cyber Science and Technology Zhejiang UniversityHangzhou 310058China

In silico prediction of self-interacting proteins(SIPs)has become an important part of *** is an urgent need to develop effective and reliable prediction methods to overcome the disadvantage of high cost and labor intensive in traditional biological wet-lab *** goal of our survey is to sum up a comprehensive overview of the recent literature with the computational SIPs prediction,to provide important references for actual work in the *** this review,we first describe the data required for the task of DTIs ***,some interesting feature extraction methods and computational models are presented on this topic in a timely ***,an empirical comparison is performed to demonstrate the prediction performance of some classifiers under different feature extraction and encoding ***,we conclude and highlight potential methods for further enhancement of SIPs prediction performance as well as related research directions.

关键词： proteomics self-interacting proteins feature extraction prediction model

An optimal coupling incentive mechanism concerning insider’s compliance behavior towards marine information security policy

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Journal of Ocean Engineering and Science 2023年第5期8卷 573-575页

作者： Xiaolong wang Changlin wang Zaiguan Sun Chunhui wang School of Economics and Management Binzhou UniversityBinzhou 256600China

It is widely agreed that the insider’s noncompliance to the marine information security policies has brought about a major security problem in the organizational *** research has stressed the potential of remunerative control,i.e.,reward,to better understand this *** studies have been devoted to the exploration of the coupling incentive mechanism of tangible and intangible rewards that would induce insider’s compliance behavior towards the marine information security *** the present study,we address this research gap by proposing a theoretical model that explains the optimal coupling incentive mechanism of these two different types of remunerative *** findings have delivered insightful implications for practice and research on how to improve the marine information security policy compliance in a more subtle way.

关键词： Marine information Information security policy Compliance behavior Incentive mechanism

La^(3+)@BC500-S_(2)O_(8)^(2−)system for removal of sulfonamide antibiotics in water

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Journal of Environmental Sciences 2024年第12期146卷 140-148页

作者： Bing wang Dongsu Bi Juan wang Hengbo Qiao Yalei Zhang Zheng Shen School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China State Key Laboratory of Pollution Control and Resources Reuse Key Laboratory of Yangtze River Water Environment of MOENational Engineering Research Center of Protected AgricultureShanghai Engineering Research Center of Protected AgricultureTongji UniversityShanghai 200092China

Sulfonamide antibiotics(SAs)widely used have potentially negative effects on human beings and *** and advanced oxidation methods have been exten-sively applied in SAs wastewater *** this study,compared with Al^(3+)@BC500 and Fe^(3+)@BC500,La^(3+)@BC500 for activating persulfate(S2O82−)had the best effect removal per-formance of sulfadiazine(SDZ)and sulfamethoxazole(SMX).Morphology,acidity,oxygen-containing functional groups,and loading of La^(3+)@BC500 were analyzed by techniques,in-cluding EA,BET,XRD,XPS,*** results show that with the increase of La^(3+)loading,the surface characteristics of biochar gradually changed from CaCO_(3)to LaCO_(3)*** EPR technology,it is proved that LaCO_(3)OH on the surface of La^(3+)@BC500 can not only acti-vate S2O82−to generate SO_(4)^(−)•,but also to produce•*** the optimization experiment,the optimal dosage of La^(3+)is between 0.05 and 0.2(mol/L)/*** had a good removal effect at pH(5-9),but SMX had a good removal effect only at pH=*** potential also proves that the material is more stable under acidic *** removal process of SDZ is more in accord with pseudo-first-order kinetics(R^(2)=0.9869),while SMX is more in line with pseudo-second order kinetics(R^(2)=0.9926).

关键词： Sulfadiazine Sulfamethoxazole La^(3+)@BC500 Persulfate

Initial corrosion behavior and mechanism of 7B04 aluminum alloy under acid immersion and salt spray environments

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Chinese Journal of Aeronautics 2022年第1期35卷 277-289页

作者： Yangguang ZHANG Yueliang CHEN Yong ZHANG Guixue BIAN Chenguang wang Andong wang Naval Aviation University Qingdao Campus Qingdao 266041China

The initial corrosion behavior and mechanism of 7B04 aluminum alloy under acid immersion and salt spray environments(pH=3.5)are studied by Scanning Electron Microscope(SEM),optical microscope,Fourier Transform Infrared Spectroscopy(FT-IR),X-Ray Diffraction(XRD),potentiodynamic polarization,Electrochemical Impedance Spectroscopy(EIS),and Scanning Kelvin Probe(SKP).The results show that pitting corrosion occurs at the initial corrosion stage,and the potential difference between the second phase particles is the main cause of *** pits on different locations gradually expand and coalesce with the proceeding of *** main components of corrosion products are Al_(2)O_(3),Al(OH)_(3),and AlCl_(3),and the generation rate of the corrosion product layer under the salt spray environment is larger than that under acid immersion *** both environments,the Volta potential distribution first disperses and then concentrates,while the charge transfer resistance first decreases and then increases with the corrosion *** Volta potential gradually shifts in a positive direction,indicating that corrosion products have an inhibitory effect on *** the same corrosion time,the corrosion product layer resistance and the expectation of the Volta potential of the salt spray sample are higher than those of the immersion ***,the corrosion current density for the salt spray sample is significantly lower than the immersion sample,which indicates that the thicker the corrosion product layer,the stronger the inhibition of corrosion reaction.

关键词： 7B04 aluminum alloy Acid salt spray Corrosion mechanism Corrosion products Electrochemistry Scanning Kelvin probe