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Science China(Physics,Mechanics & Astronomy) 2021年第8期64卷 72-77页

作者： ya-Ning Ren mo-Han Zhang Chao yan Yu Zhang Lin He Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China

Shubnikov-de Haas oscillations are the most well-known magneto-oscillations in transport measurements. They are caused by Landau quantization of two-dimensional(2D) electron systems in the presence of a magnetic field. Here we demonstrate that a scanning tunneling microscope(STM) can locally measure similar magneto-oscillations in 2D systems. In Landau level spectroscopy measurements with fine magnetic-field increments, we observed fixed-energy magnetic-field-dependent oscillations of the local density of states. From the measured tunneling magneto-conductance oscillations acquired by STM, energymomentum dispersions and Berry phases of a monolayer, Bernal-stacked bilayer, and ABC-stacked trilayer graphene were obtained. The reported method is applicable to a wide range of materials because it can obtain the magneto-oscillations of 2D systems larger than the magnetic length;importantly, it also requires no gate electrode.

关键词： graphene magneto-conductance oscillations scanning tunneling microscopy energy-momentum dispersion Berry phase

Numerical Solution of Scalar Field for Nariai Case in 5D Ricci-Flat SdS Black String Space with Polynomial Approximation

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Communications in Theoretical Physics 2008年第10期50卷 889-892页

作者： WANG Chun-Xiao LIU mo-Lin LIU Hong-ya Department of Physics Fuyang Teachers College Fuyang 236041 China School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024 China

As one exact candidate of the higher dimensional black hole, the 5D Ricci-flat Schwarzsehild-de Sitter black string space presents something interesting. In this paper, we give a numerical solution to the real scalar field around the Nariai black hole by the polynomial approximation. Unlike the previous tangent approximation, this fitting function makes a perfect match in the leading intermediate region and gives a good description near both the event and the cosmological horizons. We can read from our results that the wave is close to a harmonic one with the tortoise coordinate. Furthermore, with the actual radial coordinate the waves pile up almost equally near the both horizons.

关键词： black string real scalar field Nariai black hole polynomial approximation

Improving the sintering performance of blends containing Canadian specularite concentrate by modifying the binding medium

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International Journal of Minerals,Metallurgy and Materials 2018年第6期25卷 598-608页

作者： Feng Zhang De-qing Zhu Jian Pan ya-ping mo Zheng-qi Guo School of Minerals Processing and Bioengineering Central South University Changsha 410083 China Investment Management Department of Wuhan Iron and Steel Company Limited Wuhan 430083 China

Canadian specularite concentrate（CSC） possesses high total iron grade and low impurity content. However, due to the poor granulating performance and weak reactivity of CSC at high temperature, the proportion of CSC used in sintering blends is restricted. In this research, the effects of fine limonite, slake lime, and bentonite particles on the granulation performance of blends containing a high ratio of CSC were studied through granulation test. based on the test results, the effects of modification of the binding medium on the sintering performance of blends containing a high ratio of CSC were revealed by the sintering pot test. Both the granulation property and sintering performance of blends with a high proportion of CSC were improved by modifying the binding medium.

关键词： iron ore binding medium specula^ite concentrate sintering performance

Imaging field-tuned quantum Hall broken-symmetry orders and the quantum Hall conducting channel in a charge-neutral graphene/WSe_(2) heterostructure

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Science China(Physics,Mechanics & Astronomy) 2023年第7期66卷 88-93页

作者： Qi Zheng mo-Han Zhang ya-Ning Ren Ruo-Han Zhang Lin He Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China

The zeroth Landau level(0LL)in graphene has emerged as a flat band platform in which distinct many-body phases can be explored with unprecedented control by simply tuning the strength and/or direction of the magnetic field.A rich set of quantum Hall ferromagnetic phases with different lattice-scale symmetry-breaking orders are predicted to be realized in high magnetic fields when the 0LL in graphene is *** we report on a field-tuned continuous phase transition of different valley orderings in a quantum Hall ferromagnetic phase of charge-neutral graphene on insulating tungsten diselenide(WSe_(2)).The phase transition is clearly revealed by an anomalous field-dependent energy gap in the half-filled *** atomic resolution imaging of electronic wavefunctions during the phase transition,we unexpectedly observe the microscopic signatures of fieldtuned continuous-varied valley polarization and valley inversion,which are beyond current theoretical ***,the quantum Hall conducting channel of the graphene is directly imaged when the substrate(WSe_(2))introduces band bending of the 0LL.

关键词： graphene WSe_(2) quantum Hall ferromagnetic valley polarization valley inversion

Yunnanilus chuanheensis, a new loach species(Cypriniformes: Nemacheilidae) from the upper Lixianjiang River in Yunnan, China

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Zoological Research 2021年第2期42卷 241-245页

作者： Wan-Sheng Jiang ya-Peng Zhao Li-Na Du mo Wang Hunan Engineering Laboratory for Chinese Giant Salamander’s Resource Protection and Comprehensive Utilization and Key Laboratory of Hunan Forest and Chemical Industry EngineeringJishou UniversityZhangjiajieHunan 427000China Yunnan Key Laboratory of Plateau Fish Breeding Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Key Laboratory for Conserving Wildlife with Small Populations in Yunnan and Faculty of Biodiversity ConservationSouthwest Forestry UniversityKunmingYunnan 650224China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilinGuangxi 541004China Guangxi Key Laboratory of Rare and Endangered Animal Ecology College of Life ScienceGuangxi Normal UniversityGuilinGuangxi 541004China

DEAR EDITOR,A new loach species(Cypriniformes: Nemacheilidae:Yunnanilini), Yunnanilus chuanheensis sp. nov., was caught from Chuanhe in the upper reaches of the Lixianjiang River, a tributary of the Red River in Nanjian County, Yunnan Province, China. This species is a member of the traditional *** species group based on the presence of a lateral line and cephalic lateral-line canals.

关键词： China. ens Chuan

Serum vitamin D and vitamin-D-binding protein levels in children with chronic hepatitis B

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World Journal of Gastroenterology 2021年第3期27卷 255-266页

作者： Cai-Zhi Huang Jie Zhang Lin Zhang Cui-Hua Yu Yi mo Li-ya.mo Department of Laboratory Medicine Hunan Children’s HospitalChangsha 410007Hunan ProvinceChina Department of GCP Certified Sites The Third Hospital of Changsha CityChangsha 410005Hunan ProvinceChina

baCKGROUND Vitamin D is an essential fat-soluble secosteroid hydroxylated by the liver to form the intermediate metabolite calcidiol{25-hydroxy vitamin D[25(OH)D]},which is a reliable indicator to investigate individual vitamin D ***-D-binding protein(VDBP)is a multifunctional glycoprotein mainly synthesized in the liver and the major transport protein for vitamin D and its *** vitamin D and VDBP are both associated with hepatitis ***,few studies have reported the relationship and clinical significance of vitamin D and VDBP with hepatitis B virus(HBV)replication and hepatic fibrosis in children with chronic hepatitis B(CHB).AIM To explore vitamin D and VDBP serum levels in children with CHB and the association of vitamin D and VDBP with HBV replication and hepatic *** We enrolled 204 children with CHB admitted to Hunan Children’Hospital in summer and autumn between 2018 and 2019 and 170 healthy *** patients included:164 hepatitis B e antigen(HBeAg)positive and 40 HBeAg negative;193 hepatitis B surface antigen(HBsAg)positive and 11 HBsAg negative;164 with detectable HBV deoxyribonucleic acid(DNA)and 40 with undetectable HBV DNA;131 with HBV genotype B and 23 with HBV genotype C;and 27 without hepatic fibrosis and 97 with hepatic *** levels of 25(OH)D,VDBP,liver function markers,and other clinical parameters were collected to analyze their association with vitamin D and ***-Whitney U test,Kruskal-Wallis H test,or t test was used to analyze serum 25(OH)D and VDBP levels in different *** rank correlation test was utilized to analyze the correlation of 25(OH)D and VDBP with other *** significant factors determined by univariate analysis were further analyzed by binary multivariate logistic regression analysis.PmoL/L)and VDBP[122.40(70.74-262.84μg/L)]levels than hea

关键词： Chronic hepatitis B Children Vitamin D Vitamin-D-binding protein Hepatitis B virus

Recent Advances in Carbon-based Adsorbents for Adsorptive Separation of Light Hydrocarbons

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Research 2022年第4期2022卷 261-281页

作者： Yong-Sheng Wang Xue-Jie Zhang ya-Qi ba Tian-Yi Li Guang-Ping Hao An-Hui Lu State Key Laboratory of Fine Chemicals Liaoning Key Laboratory for Catalytic Conversion of Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

Light hydrocarbons(LHs)separation is an important process in petrochemical *** current separation technology predominantly relies on cryogenic distillation,which results in considerable energy *** separation using porous solids has received widespread attention due to its lower energy footprint and higher ***,tremendous efforts have been devoted to the design and synthesis of high-performance porous *** them,porous carbons display exceptional stability,tunable pore structure,and surface chemistry and thus represent a class of novel adsorbents upon achieving the matched pore structures for LHs *** this review,the modulation strategies toward advanced carbonbased adsorbents for LHs separation are firstly ***,the relationships between separation performances and key structural parameters of carbon adsorbents are discussed by exemplifying specific separation *** research findings on the control of the pore structures as well as the quantification of the adsorption sites are ***,the challenges of carbonaceous adsorbents facing for LHs separation are given,which would motivate us to rationally design more efficient absorbents and separation processes in future.

关键词： separation adsorbent porous

Three-dimensional coupled-mode model and characteristics of low-frequency sound propagation in ocean waveguide with seamount topography

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Chinese Physics B 2022年第8期31卷 453-462页

作者： ya-Xiao mo Chao-Jin Zhang Li-Cheng Lu Sheng-Ming Guo Key Laboratory of Underwater Acoustic Environment Institute of AcousticsChinese Academy of SciencesBeijing 100190China China State Shipbuilding Corporation Systems Engineering Research Institute Beijing 100094China

Large-scale topography, such as a seamount, substantially impacts low-frequency sound propagation in an ocean waveguide, limiting the application of low-frequency acoustic detecting techniques. A three-dimensional(3D) coupledmode model is developed to calculate the acoustic field in an ocean waveguide with seamount topography and analyze the3D effect. In this model, a correction is introduced in the bottom boundary, theoretically making the acoustic field satisfy the energy conservation. Furthermore, a large azimuth angle calculation range is obtained by using the operator theory and higher-order Pade approximation. Additionally, the model has advantages related to the coupling mode and parabolic equation theory. The couplings corresponding to the effects of range-dependent environment are fully considered, and the numerical implementation is kept feasible. After verifying the accuracy and reliability of the model, low-frequency sound propagation characteristics in the seamount environment are analyzed. The results indicate lateral variability in bathymetry can lead to out-of-plane effects such as the horizontal refraction phenomenon, while the coupling effect tends to restore the abnormal sound field and produces acoustic field diffraction behind the seamount. This model effectively considers the effects of the horizontal refraction and coupling, which are proportional to the scale of the seamount.

关键词： coupled-mode model three-dimensional sound propagation seamount topography horizontal interference structure

A new extension algorithm for cubic B-splines based on minimal strain energy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 2043-2049页

作者： mo Guo-liang ZHAO ya-nan Department of Information and Computational Science Zhejiang University City College Hangzhou 310015 China

Extension of a B-spline curve or surface is a useful function in a CAD system. This paper presents an algorithm for extending cubic B-spline curves or surfaces to one or more target points. To keep the extension curve segment GC^2-continuous with the original one, a family of cubic polynomial interpolation curves can be constructed. One curve is chosen as the solution from a sub-class of such a family by setting one GC^2 parameter to be zero and determining the second GC^2 parameter by minimizing the strain energy. To simplify the final curve representation, the extension segment is reparameterized to achieve C-continuity with the given B-spline curve, and then knot removal from the curve is done. As a result, a sub-optimized solution subject to the given constraints and criteria is obtained. Additionally, new control points of the extension B-spline segment can be determined by solving lower triangular linear equations. Some computing examples for comparing our method and other methods are given.

关键词： GC^2-continuous Extension Minimal strain energy Knot removal Reparametrization

Knowledge,Attitude,and Perception of Postmortem Examination Among Doctors and Nurses in a Tertiary Hospital of Sokoto,Nigeria

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Journal of Forensic Science and Medicine 2016年第2期2卷 78-84页

作者： Kaoje AU mohammed U Abdulkarim A Raji mo Ango UM Magaji ba Departments of Community Health and 1morbid Anatomy and Forensic Medicine Usmanu Danfodiyo University Department of Surgery Usmanu Danfodiyo University Teaching Hospital Department of Medical Services and Public Health Ministry of HealthSokotoNigeria Department of Social and Preventive Medicine University of MalayaKuala LumpurMalaysia

Postmortem examination is a highly specialized surgical procedure that consists of a thorough examination of a corpse to determine the cause and manner of death and to evaluate any disease or injury that may be *** study aimed to assess the knowledge,attitude,and perception of postmortem examination among doctors and nurses in a tertiary health care of Sokoto state.A cross‑sectional study design was used,and a total of 149 doctors and nurses participated in the *** were recruited into the study using probability proportionate to size followed by a simple random sampling *** were obtained through self‑administered questionnaires,and the data were analyzed using Statistical Package for Social Sciences Version *** statistics,Chi‑square test,and multinomial logistic regression analysis were carried *** mean age of respondents was 31.6(5.6)*** were more nurses than doctors(60.4%vs.39.6%)in the *** than three‑quarter(80%)of the respondents had fair to good knowledge of postmortem *** many respondents expressed positive attitudes and perceptions,less than half were willing to accept organs from deceased ***’profession influenced both the knowledge(P>0.001,odds ratio[OR]=13.95)and attitude(Pmortem *** greater than three‑quarter of respondents had fair to good knowledge and many expressed positive attitudes and perceptions with respect to postmortem examination,there is need to create more awareness on medical benefit of postmortem examination.

关键词： Attitude health personnel knowledge perception postmortem Sokoto