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event plane determination from the zero degree calorimeter at the cooling storage ring external-target experiment

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nuclear Science and Techniques 2023年第7期34卷 113-121页

作者： Li-Ke Liu Hua Pei Ya-Ping Wang Biao Zhang nu Xu Shu-Su Shi Key Laboratory of Quark and Lepton Physics(MOe)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China

The Cooling Storage Ring external-target experiment(Cee)spectrometer is used to study the nuclear matter created in heavy-ion collisions at√sNN=2.1-2.4 GeV with the aim to reveal the quantum chromodynamics phase structure in the high-baryon-density *** flow is considered an effective probe for evaluating the properties of media during high-energy nuclear *** of the main functions of the zero-degree calorimeter(ZDC),a subdetector system in the Cee,is to determine the reaction plane in heavy-ion *** step is crucial for measuring the collective flow and other reaction-plane-related *** this paper,we illustrate the procedures for event plane determination using the ***,isospin-dependent quantum molecular dynamics model-based predictions of the rapidity dependence of the directed and elliptical flows for p,d,t,3He,and 4He,produced in 2.1 GeV U+U collisions,are presented.

关键词： QCD phase structure Heavy-ion collisions Collective flow Reaction plane Zero-degree calorimeter

Preparation and Photoluminescence of ZnO Nanostructures

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Chinese Journal of Aeronautics 2006年第B12期19卷 210-214页

作者： YAN Jin-liang ZHAO Yin-nu SUN Xue-qing GUO Chun School of Physics and electronic engineering Ludong University Yantai 264025 China Dean＇s Office Ludong University Yantai 264025 China

Porous anodic alumina （PAA） hosts with ZnO nanoparticles loaded in were prepared by immersing PAA films in an aqueous solution of zinc acetate and then annealing at high temperatures. Highly ordered ZnO nanodot arrays were produced using the method in combination of PAA template with RF magnetron sputtering deposition. The photoluminescence of the ZnO/PAA composite and the highly ordered ZnO nanodot arrays were investigated by means of a fluorescent spectrometer. The ZnO/PAA composite exhibits intense and broad photoluminescence spectra with the peak position at around 485 nm. The ZnO nanodot arrays have a strong UV light emissive peak at about 380 nm and a wide light emissive peak at 460 nm-610 nm at the room temperature.

关键词： photoluminescence nanodot array nanoparticle zinc oxide

Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： J.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

estimating costs of salvage logging for large-scale burned forest lands: A case study on Turkey's Mediterranean coast

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Journal of Forestry Research 2021年第5期32卷 1899-1909页

作者： Neşe Gülci Faculty of Forestry Kahramanmaras Sutcu Imam University46100 KahramanmarasTurkey

Different forest fires causing different degrees of effects occur in fire-sensitive forests due to various reasons such as climate *** as well as harmful aspects of forest fires are a multi-disciplinary research *** information systems(GIS)and remote sensing(RS)methods offer a number of benefits for researchers and operators in the field of forest fire *** present study analyses timber pricing based on forest contractor demands of post-salvage logging *** effect of timber obtained from compartment units on producers’pricing policy was *** forest fire area(2500 ha)located in Antalya in Turkey was selected as the main study *** parameters(aspect,slope and slope position),stand types(diameter class and crown closure),and burn severity were analyzed together using GIS and R software packages.A multi-linear regression model(R^(2)=0.752)demonstrated that factors that had the most impact on pricing were slope position,aspect,stand age,crown closure and burn *** model can be used to estimate salvage logging prices in Calabrian pine(Pinus brutia Ten.)stands with similar *** administrators and contractors may readily address the unit price of timber by estimating approximate costs in a given forest area for which they are going to *** will help reduce operational planning times of harvesting procedures in burned stands.

关键词： Timber extraction Forest fires Stumpage sale Cost estimation Sustainability Crown fire

Influence of the Choice of NN Potential Model on γd→τ~0d Observables near η-Threshold

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Chinese Physics Letters 2016年第4期33卷 14-18页

作者： e.M.Darwish Physics Department Faculty of ScienceTaibah University Physics Department Faculty of ScienceSohag University

Influence of the choice of the NN potential model governing the deuteron wave function on the observables for coherent π0-photoproduction on the deuteron near η-threshoM is investigated by using a three-body model for the intermediate ηN N system with separable two-body interactions. Results for unpolarized differential cross section and polarization observables are predicted. It is revealed that the choice of the NN potential model has a visible effect on the differential cross section and most of the polarization observables, especially in the photon energy range of 600-800 MeV and extreme backward pion angles. We find that the deviation among results obtained by using different deuteron wave functions is quite large. The use of the CD-Bonn NN potential for deuteron wave function doubles the differential cross section in this kinematic region. Compared with the experimental data from CLAS collaboration for differential cross section, sizeable discrepancies are found.

关键词： of in Observables near Threshold NN that for on CLAS

exploring the mass gap:Black holes in green pea galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 170-171页

作者： James e.Rhoads School of earth and Space exploration Arizona State UniversityTempeAZ 85287USA

We know about black holes primarily on two mass scales(e.g.,see Figure 22 of ref.[1]).Supermassive black holes inhabit the centers of galaxies,where they sometimes power active galactic nuclei(AGN).Their populations can be probed through AGN surveys,tidal disruption event surveys,and(in the closest galaxies)stellar and gas dynamics in the innermost regions where the black hole dominates the gravitational potential.

关键词： galaxies tidal galactic

effect of water on behaviour of Na_2B_4O_7·5H_2O and Na_2B_4O_7 in HCl-CH_3OH medium

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Transactions of Nonferrous Metals Society of China 2010年第8期20卷 1541-1544页

作者： A.e.eRTAS .GIRGIN Mining engineering Department Hacettepe University

The reactivity of Na2B4O7·5HaO and Na2B4O7 in non-aqueous HCl-CH3OH solvent system was investigated. The effects of H2O, CH3OH/B mole ratio and reaction time on the reaction at room temperature were examined. experimental results show that when Na2B4O7·5H2O and Na2B4O7 are the reactants, the dissolved B203 contents are observed to be 98.2% and 99%, respectively, in 5min at the CH3OH/B mole ratio of 4. The decrease of water in the reaction medium was observed to increase the crystallization of NaCI in the order of Na2B4O7〉Na2B4O7·5H2O It was also observed that the boron solution obtained after the reaction could be hydrolyzed by the addition of H3BO3. The results show that HCl-CH3OH system is a more effective solvent compared to H2SO4-CH3OH both in the reactivity and the shortened reaction time.

关键词： non-metallic ores oxide ores hydrometallurgy leaching

ASYMPTOTIC LIMITS AND STABILIZATION FOR THe 1D NONLINeAR MINDLIN-TIMOSHeNKO SYSTeM

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Journal of Systems Science & Complexity 2010年第3期23卷 414-430页

作者： F.D.ARARUNA P.BRAZ e SILVA e.ZUAZUA Departamento de Matemática Universidade Federal da Paraíba Departamento Ikerbasque Research Professor Basque Center for Applied Mathematics(BCAM)

This paper shows how the so called von Karman model can be obtained as a singular limit of a modified Mindlin-Timoshenko system when the modulus of elasticity in shear κ tends to infinity, provided a regularizing term through a fourth order dispersive operator is added. Introducing damping mechanisms, the authors also show that the energy of solutions for this modified Mindlin-Timoshenko system decays exponentially, uniformly with respect to the parameter k. As κ→∞, the authors obtain the damped von Karman model with associated energy exponentially decaying to zero as well.

关键词： Mindlin-Timoshenko system singular limit uniform stabilization vibrating beams von Karman system.

Classifier for centrality determination with zero-degree calorimeter at the cooling-storage-ring external-target experiment

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nuclear Science and Techniques 2023年第11期34卷 168-173页

作者： Biao Zhang Li‑Ke Liu Hua Pei Shu‑Su Shi nu Xu Ya‑Ping Wang Key Laboratory of Quark and Lepton Physics(MOe)and Institute of Particle Physics Central China Normal UniversityWuhan 430079China

The zero-degree calorimeter(ZDC)plays a crucial role toward determining the centrality in the Cooling-Storage-Ring external-target experiment(Cee)at the Heavy Ion Research Facility in Lanzhou.A boosted decision tree(BDT)multi-classification algorithm was employed to classify the centrality of the collision events based on the raw features from ZDC such as the number of fired channels and deposited *** data from simulated^(238)U+^(238)U collisions at 500 MeV∕u,generated by the IQMD event generator and subsequently modeled using the GeANT4 package,were employed to train and test the BDT *** results showed the high accuracy of the multi-classification model adopted in ZDC for centrality determination,which is robust against variations in different factors of detector geometry and *** study demon-strates the good performance of Cee-ZDC in determining the centrality in nucleus-nucleus collisions.

关键词： ZDC Boosted decision trees Multi-classification IQMD Centrality determination