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Key factor for determining relation between radius and tidal deformability of neutron stars: Slope of symmetry energy

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Chinese Physics C 2020年第6期44卷 103-108页

作者： Nai-Bo Zhang Bin Qi shou-yu wang Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihai 264209China

The constraints on tidal deformability Λ of neutron stars were first extracted from GW170817 by LIGO and Virgo ***,the relationship between the radius R and tidal deformability Λ is still under *** an isospin-dependent parameterized equation of state(EOS),we study the relation between R andΛand its dependence on parameters of symmetry energy Esym and EOS of symmetric nuclear matter E0 when the mass is fixed at 1.4 M⊙,1.0 M⊙,and 1.8 M⊙.We find that,although the changes of high order parameters of Esym and E 0 can shift individual values of R1.4 and Λ1.4,the R1.4~Λ1.4 relation remains approximately at the same fitted *** slope L of the symmetry energy plays the dominant role in determining the R1.4~Λ1.4 *** investigating the mass dependence of the R~Λ relation,we find that the well fitted R~Λ relation for 1.4 M⊙ is broken for massive neutron stars.

关键词： neutron stars symmetry energy tidal deformability radius

Alternating Parity Band in Octupole-Soft ^(140)Xe with Axial Vibrational-Rotational Model and Triaxial Rigid Rotor Model

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Chinese Physics Letters 2018年第10期35卷 9-13页

作者： Xiao Lu Bin Qi shou-yu wang Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Institute of Space Sciences Shandong University

Energies of the yrast positive-and negative-parity excited states in140 Xe are reproduced by two different models considering quadrupole-octupole deformations, namely the axial vibrational-rotational model and the triaxial rigid rotor model, and compared with the stable octupole-deformed222 Th. The origin of the energy difference between the opposite parity sequences is considered from two different mechanisms, the vibration in axial deformed energy minima and the rotation considering the effective triaxial deformation. The success of reproducing the data in both the models implies that these two mechanisms are equivalent on some level for the octupole-soft nuclei. By investigating the probability distributions for projection of total angular momentum in the triaxial rigid rotor model, it is found that such an energy difference is associated with the difference of orientation of the rotational axis.

关键词： Alternating Parity Band in Octupole-Soft Xe with Axial Vibrational-Rotational Model and Triaxial Rigid Rotor Model

Possible candidate nuclei for chirality-parity quartet bands

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Chinese Physics C 2018年第7期42卷 82-88页

作者： Chen Liu shou-yu wang Bin Qi Hui Jia Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Weihai 264209 China

The potential energy surfaces of the even-even 68-92Se, 112-150Ba, and 208-230Ra isotopes are calculated using the macroscopic-microscopic method in a multidimensional space {αλ,μ} including quadrupole （λ=2, μ=0, 2） and octupole （λ=3, μ=0, 1, 2, 3） degrees of freedom. The calculated results show that the even-even isotopes 92Se, 112,114,144-150Ba and 220-228Ra can exhibit the coexistence of triaxial and octupole deformations, thereby leading to simultaneous chiral and reflected symmetry breaking. Therefore, chirality-parity quartet bands are expected in these and their neighboring odd-A/odd-odd nuclei.

关键词： chiral doublet bands shape coexistence chirality-parity quartet bands macroscopic-microscopic method

Electromagnetic transitions in multiple chiral doublet bands

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Chinese Physics C 2016年第12期40卷 91-98页

作者： Hui Jia Bin Qi shou-yu wang Shuo wang Chen Liu Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Weihai 264209 China

Multiple chiral doublet bands （MχD） in the 80, 130 and 190 mass regions are studied by the model of γ=90°triaxial rotor coupled with identical symmetric proton-neutron configurations. By selecting a suitable basis, the calculated wave functions are explicitly exhibited to be symmetric under the operator A, which is defined as rotation by 90° about the 3-axis with the exchange of valance proton and neutron. We found that both M1 and E2 transitions are allowed between levels with different values of A, while they are forbidden between levels with same values of A. Such a selection rule holds true for MχD in different mass regions.

关键词： chiral doublet bands electromagnetic transition selection rule particle rotor model

A key factor to the spin parameter of uniformly rotating compact stars: crust structure

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Research in Astronomy and Astrophysics 2016年第4期16卷 63-70页

作者： Bin Qi Nai-Bo Zhang Bao-yuan Sun shou-yu wang Jian-Hua Gao Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University School of Nuclear Science and Technology Lanzhou University Key Laboratory of Special Function Materials and Structure Design Ministry of Education

We study the dimensionless spin parameter j ≡ cJ/（GM2） of different kinds of uniformly rotating compact stars, including traditional neutron stars, hyperonic neutron stars and hybrid stars, based on relativistic mean field theory and the MIT bag model. It is found that j ~ 0.7, which had been suggested in traditional neutron stars, is sustained for hyperonic neutron stars and hybrid stars with M 〉 0.5 MG. Not the interior but rather the crust structure of the stars is a key factor to determine jmax for three kinds of selected compact stars. Furthermore, a universal formula j = 0.63（f/fK） -- 0.42（f/fK）2 ＋ 0.48（f/fK）z is suggested to determine the spin parameter at any rotational frequency f smaller than the Keplerian frequency fK.

关键词： stars: neutron -- stars: rotation -- spin parameter-- equation of state -- methods: numerical

Possible existence of chiral and multiple chiral nuclei in thallium isotopes

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Chinese Physics C 2022年第7期46卷 149-158页

作者： Rui-Ju Guo Xiao Lu Bin Qi Chen Liu shou-yu wang Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China

The chirality in thallium isotopes is investigated using the adiabatic and configuration-fixed constrained triaxial relativistic mean field theory. Several minima with prominent triaxial deformation and proper configuration,where the chiral doublet bands may appear, are obtained in odd-odd nucleiTl and odd-mass nucleiTl. Furthermore, the possible existence of multiple chiral doublet bands(MχD)is demonstrated inTl. As the chiral doublet bands inTl and MχD inTl have been observed experimentally, further experimental exploration for the chirality inTl and MχD in thallium isotopes is expected to verify the predictions.

关键词： chirality relativisticmean field theory thallium isotopes

Trial application of the envelope method to the potential ambiguity problem

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Nuclear Science and Techniques 2024年第1期35卷 73-80页

作者： Li-yuan Hu yu-shou Song Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin Engineering UniversityHarbin 150001China College of Nuclear Science and Technology Harbin Engineering UniversityHarbin 150001China Key Laboratory of Nuclear Safety and Advanced Nuclear Energy Technology Ministry of Industry and Information TechnologyHarbin 150001China

The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering *** a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farside scattering *** contrast,the envelope method can decompose the experimental data into two components with negative and positive deflection angles,***,a question arises as to whether the comparison between the calculated nearside(or farside)component and the derived positive-deflection-angle(or negative-deflection-angle)component can help analyze the potential ambiguity *** this study,we conducted a trial application of the envelope method to the potential ambiguity *** envelope method was improved by including uncertainties in the experimental *** colliding systems of 16O+28Si at 215.2 MeV and 12C+12C at 1016 MeV were considered in the *** each colliding system,the angular distribution experimental data were described nearly equally well by two potential sets,one of which is“surface transpar-ent”and the other is *** calculated angular distributions were decomposed into nearside and farside scattering *** the improved envelope method,the experimental data were decomposed into the positive-deflection-angle and negative-deflection-angle components,which were then compared with the calculated nearside and farside *** capability of the envelope method to analyze the potential ambiguities was also discussed.

关键词： Elastic scattering Optical potential ambiguities Envelope method Nearside/farside decomposition

Fracture geometry and breakdown pressure of radial borehole fracturing in multiple layers

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Petroleum Science 2024年第1期21卷 430-444页

作者： yu-Ning Yong Zhao-Quan Guo shou-Ceng Tian Lu-Yao Ma Tian-yu wang Mao Sheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Beijing Petroleum Machinery Company Limited CNPC Engineering Technology R&D Company LimitedBeijing102206China Smart Energy Co. LtdChina Xiongan GroupXiong’an New Area071000HebeiChina

Radial borehole fracturing that combines radial boreholes with hydraulic fracturing is anticipated to improve the output of tight oil and gas *** paper aims to investigate fracture propagation and pressure characteristics of radial borehole fracturing in multiple layers.A series of laboratory experiments with artificial rock samples(395 mm×395 mm×395 mm)was conducted using a true triaxial fracturing *** crucial factors corresponding to the vertical distance of adjacent radial borehole layers(vertical distance),the azimuth and diameter of the radial borehole are *** results show that radial borehole fracturing in multiple layers generates diverse fracture *** types of fractures are identified based on the connectivity between hydraulic fractures and radial *** vertical distance significantly influences fracture propagation perpendicular to the radial borehole *** increase in the vertical distance impedes fracture connection across multiple radial borehole layers and reduces the fracture propagation distance along the radial borehole *** azimuth also influences fracture propagation along the radial borehole *** the azimuth reduces the guiding ability of radial boreholes,which makes the fracture quickly curve to the maximum horizontal stress *** breakdown pressure correlates with diverse fracture geometries *** the fractures connect multi-layer radial boreholes,increasing the vertical distance decreases the breakdown *** the azimuth and increasing the diameter also decrease the breakdown *** extrusion force exists between the adjacent fractures generated in radial boreholes in multiple rows,which plays a crucial role in enhancing the guiding ability of radial boreholes and results in higher breakdown *** research provides valuable theoretical insights for the field application of radial borehole fracturing technology in tight oil and g

关键词： Multi-layer radial boreholes Hydraulic fracturing Fracture propagation Pressure characteristic

Crude extract of maggots:Antibacterial effects against Escherichia coli,underlying mechanisms,separation and purification

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World Journal of Gastroenterology 2015年第5期21卷 1510-1517页

作者： Quan-Sheng Ge Hui-Min Zhang Xia Liu shou-yu wang De-Cheng Lv Xu-Dong Li the First Affiliated Hospital of Dalian Medical University

AIM:To investigate the antibacterial effects of a crude extract of maggots against Escherichia coli(***) and the underlying mechanisms,and to separate and purifythe crude extract of maggots to assess the antibacterial effects of the active ingredients in the crude ***:Different concentrations of the crude extract of maggots were incubated with ***(O157:H7) and *** optical density(OD) was measured at different time points to plot the OD-T *** effects of different concentrations of the crude extract on bacterial membrane permeability were determined by fluorescence probe *** effects of different concentrations of the crude extract on plasmid DNA replication were determined by agarose gel ***-Sepharose ion exchange chromatography and Sephacryls-200 HR gel filtration chromatography were used to separate and purify the crude extract of *** molecular weight of proteins in the purified crude extract was determined by SDS-PAGD electrophoresis,and its antibacterial effects were determined by turbidimetric ***:The antibacterial effects of the crude extract of maggots at concentrations > 0.5 mg/m L were *** antibacterial effects of the crude extract at concentrations of 1.0,1.5 and 2.0 mg/m L did not differ *** probe analysis showed that the rate of membrane permeability change was 1223.1% in bacteria incubated with 2 mg/m L of the crude extract,and 1300.0% in those incubated with 80 mg/m L of the crude *** DNA was undetectable in *** incubated with 2 and 80 mg/m L of the crude extract.A low molecular weight protein band(about 15 k Da) was detected in the crude extract of maggots and eluent,but not in eluant,from DEAE-Sepharose ion exchange *** antibacterial effects of the crude extract of maggots and eluent were superior to those of eluant,with the antibacterial effects of eluents being better than those of the crude extract of maggot

关键词： Maggots Antibacterial peptide Antibacterial mechan