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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

Enhancing catalytic selectivity and stability for CO2 hydrogenation to methanol using a solid-solution catalyst

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National Science Review 2018年第5期5卷 607-608页

作者： Jingguang g.Chen Department of Chemical Engineering Columbia University Chemistry Department Brookhaven National Laboratory

The catalytic hydrogenation of COwith renewable Hrepresents a promising pathway for reducing *** the various hydrogenation products, the formation of methanol (CO+3H→CHOH+HO) is preferred because methanol can be used not only as a fuel but also as a reactant to produce olefins and other value-added chemicals[1]. Due to the chemical inertness of CO, its catalytic conversion to methanol

关键词： CO ZnO

Energy level splitting of a 2D hydrogen atom with Rashba coupling in non-commutative space

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Communications in Theoretical Physics 2020年第12期72卷 116-122页

作者： S Aghababaei g Rezaei Department of Physics College of SciencesYasouj UniversityYasouj75918-74934Iran

We explore the non-commutative(NC)effects on the energy spectrum of a two-dimensional hydrogen *** consider a confined particle in a central potential and study the modified energy states of the hydrogen atom in both coordinates and momenta of non-commutativity *** considering the Rashba interaction,we observe that the degeneracy of states can also be removed due to the spin of the particle in the presence of NC *** obtain the upper bounds for both coordinates and momenta versions of NC parameters by the splitting of the energy levels in the hydrogen atom with Rashba ***,we find a connection between the NC parameters and Lorentz violation parameters with the Rashba interaction.

关键词： quantum mechanics non-commutative space spin–orbit interaction

Quantum Effects on Rayleigh-Taylor Instability of Incompressible Plasma in a Vertical Magnetic Field

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Chinese Physics Letters 2010年第12期27卷 132-135页

作者： g. A. Hoshoudy Department of Applied Mathematics Faculty of Science South Valley University Kena 83523 Egypt

Quantum effects on Rayleigh-Taylor instability of a stratified incompressible plasmas layer under the influence of vertical magnetic field are investigated. The solutions of the linearized equations of motion together with the boundary conditions lead to deriving the relation between square normalized growth rate and square normalized wave number in two algebraic equations and are numerically analyzed. In the case of the real solution of these two equations, they can be combined to generate a single equation. The results show that the presence of vertical magnetic field beside the quantum effect will bring about more stability on the growth rate of unstable configuration.

关键词： Plasma physics

Creating the perfect plasmonic wave

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Light(Science & Applications) 2022年第9期11卷 1948-1949页

作者： günter Steinmeyer Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy BerlinGermany Institute of Physics Humboldt UniversityBerlinGermany

Exploiting a plasmonic resonance,near-perfect grating structures have been reported,with a regularity that exceeds typical commercially available diffraction gratings.

关键词： perfect regularity plasmon

Phantom Accretion onto the Schwarzschild de-Sitter Black Hole

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Chinese Physics Letters 2011年第9期28卷 34-37页

作者： M Sharif g Abbas Department of Mathematics University of the PunjabQuaid-e-Azam CampusLahore-54590Pakistan

We deal with phantom energy accretion onto the Schwarzschild de-Sitter black *** energy flux conservation,relativistic Bernoulli equation and mass flux conservation equation are formulated to discuss the phantom *** discuss the conditions for critical *** is found that the mass of the black hole decreases due to phantom *** exist two critical points which lie in the exterior of horizons(black hole and cosmological horizons).The results for the phantom energy accretion onto the Schwarzschild black hole can be recovered by takingΛ→0.

关键词： accretion horizon black

Modeling of microstructural evolution and flow stress of aluminium alloy during thermomechanical process

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中国有色金属学会会刊：英文版 2004年第3期14卷 491-495页

作者：沈健 g.gottstein general Research Institute for Nonferrous Metals Institut für Metallkunde und Metallphysik

The evolution of microstructural variables, including the densities of mobile dislocation, immobile dislocation at the cell interiors, immobile dislocation in the cell walls, as well as total dislocation density, of an Al-Mg-Si aluminium alloy during thermomechanical processing were simulated based on a three-internal-variables-model (3IVM) involving dislocation climb and interaction. Optimization was carried out to fit the calculated stress—strain curves to the experimental data of the Al-Mg-Si alloy with minimum mean deviation. Precipitations were taken into consideration of modeling. The stress—strain curves predicted by the kinetic equations of state in the 3IVM have a good agreement with the experimental data.

关键词：铝合金热机械处理显微结构流动压力 Al-Mg-Si 建模位错

Microscopic shell-model description of irrotational-flow dynamics in^(102)Pd

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Chinese Physics C 2024年第1期48卷 82-93页

作者： H.g.ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

The structure of the low-lying collective excitations in 102Pd is examined within the recently proposed microscopic shell-model version of the Bohr-Mottelson(BM)collective model.A good description of the excitation energies of the lowest ground,γ,andβbands,as well as the staggering function between the collective states of theγband and some other energy-dependent quantities,is *** low-energy intraband and interband quadrupole dynamics is reasonably well described within the present proton-neutron sympletic based shell-model approach without the use of an effective charge and compared with the predictions of nuclear structure *** obtained results of the present study shed light on the question of the existence of irrotational-flow type quadrupole dynamics,which lies on the ground of the original BM model of quantized vibrations and surface-wave rotations in atomic nuclei.

关键词： shell-model version of the Bohr-Mottelson model irrotational-flow dynamics proton-neutron symplectic model Sp(12,R)dynamical algebra

Dirac Points in Two-Dimensional Inverse Opals

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Chinese Physics Letters 2013年第10期30卷 164-166页

作者： g.D.Mahan Department of Physics Pennsylvania State UniversityUniversity ParkPA 16802USA

The electron energy states and energy bands are calculated for a two-dimensional inverse opal *** that the opal structure is closed-packed circles,the inverse opal has the honeycomb *** honeycomb lattice in two dimensions has a Diract *** properties can be manipulated by altering the structure of the inverse opal:the radius of the circle,and the small gap between circles.

关键词： structure inverse Dirac

Discussion of sources of error in laser-speckle based systems

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Chinese Optics Letters 2011年第7期9卷 41-44页

作者： Bernhard g.Zogar Institute for Measurement Technology Johannes Kepler University Altenbergerstraβe 69 4040 Linz Austria

Applying laser-speckle techniques in material sciences as well as in methods to characterize surface con- ditions of specimen has become the method of choice, especially if a non-contacting principle is sought. This is almost always the case for specimen that are small in at least one dimension as for example in the materiM testing of foils, fibres, or micromaterials and certainly also if elevated test-temperatures are preventing standard gauges. This letter discusses in some detail sources of error that are quite often over- looked or not even considered as significant at all, but still carry the potential to introduce uncertainties well above the system design specifications.

关键词： Discussion of sources of error in laser-speckle based systems