LIU Rixin NING Baolin ** Dept.of Metallurgy
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Kunming Institute of Technology
,
Kunming
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650093
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China*** Dept.of Thermal Energy
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Northeast University of Technology
,
Shenyang
,
110006
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China+ To whom correspondence should be addressed
材料科学技术（英文）
This paper provides a mathematical model for the billet reheating process in furnace.A new optimum method is brought up that the objective function is the integral value of enthalpy increasing process of a billet.Different delays are simulated and calculated,some proper delay strategies are ob- tained.The on-line computer control model is de- veloped.The real production conditions simulated, the temperature deviation of drop out billet from the target temperature is kept within±15℃.
关键词:
reheating furnace
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null
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null
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null
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null
SUN Wenqiang
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CAI Jiuju
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MAO Hujun
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GUAN Duojiao
钢铁研究学报(英文版)
As the largest energy consuming manufacturing sector and one of the most important sources of carbon dioxide (CO2) emissions, the China′s iron and steel industry has paid attention to the study of changing trend and influencing factors of CO2 emissions from energy use. The logarithmic mean Divisia index (LMDI) technique is used to decompose total change in CO2 emissions into four factors: emission factor effect, energy structure effect, energy consumption effect, and steel production effect. The results show that the steel production effect is the major factor which is responsible for the rise in CO2 emissions; whereas the energy consumption effect contributes most to the reduction in CO2 emissions. And the emission factor effect makes a weak negative contribution to the increase of CO2 emissions. To find out the detailed relationship between change in energy consumption or steel production and change in CO2 emissions, the correlation equations are also proposed.
关键词:
CO2 emissions
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energy use
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LMDI technique
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steel production
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energy consumption
Journal of Materials Research
Effects of stacking fault energy (SFE) on the thermal stability and mechanical properties of nanostructured (NS) Cu-Al alloys during thermal annealing were investigated in this study. Compared with NS Cu-5at.% Al alloy with the higher SFE, NS Cu-8at.% Al alloy exhibits the lower critical temperatures for the initiation of recrystallization and the transition from recovery-dominated to recrystallization-dominated process, which significantly signals its low thermal stability. This may be attributed to the large microstructural heterogeneities resulting from severe plastic deformation. With increasing the annealing temperatures, both Cu-Al alloys present the similar trend of decreased strength and improved ductility. Meanwhile, the remarkable enhancement of uniform elongation is achieved when the volume fraction of Static recrystallization (SRX) grains exceeds similar to 80%. Moreover, the better strength-ductility combination was achieved in the Cu-8at.% Al alloy with lower SFE.
关键词:
electron backscatter diffraction;dynamic plastic-deformation;aluminum;single-crystals;microstructural evolution;ultrahigh-strength;grain-refinement;shear bands;copper;recrystallization;ductility
Communications in Theoretical Physics
Traditional ligand-field theory has to be improved by taking into account both "pure electronic" contribution and electron-phonon interaction one (including lattice-vibrational relaxation energy). By means of improved ligand-field theory, R-1, R-2, R-3', R-2', and R-1' lines, U band, ground-state zero-field-splitting (GSZFS) and ground-state g factors as well as thermal shifts of R-1 line and R-2 line of yAG:Cr3+ have been calculated. The results are in very good agreement with the experimental data. In contrast with ruby, the octahedron of ligand oxygen ions surrounding the central Cr3+ ion in YAG:Cr is compressed along the [111] direction. Thus, for YAG:Cr3+ and ruby, the splitting of t(2)(3) (4)A(2) (or t(2)(3) E-2) has opposite order, and the trigonal-field parameters of the two crystals have opposite signs. In thermal shifts of R-1 and R-2 lines of YAG:Cr3+, the temperature-dependent contributions due to EPI are dominant.
关键词:
improved ligand-field theory;electron-phonon interaction;Stokes shift;energy spectrum;thermal shift;g factor;yttrium-aluminum-garnet;pressure;cr3;temperature;state;ions
International Journal of Modern Physics B
The dynamic behaviors of the new soliton in the improved Davydov model in the protein molecules at biological temperature have been numerically simulated by utilizing the dynamic equations for the bio-energy transport and the Runge-Kutta way. in this simulation the influences of the temperature and structure disorders of the protein molecules on the soliton transporting the bio-energy have been completely considered. We find that the new soliton is quite stable in die cases of motion of a long time of 300 ps and of disorders of the structures of the proteins at; biological temperatures of 300 K-320 K. The disorders of the structures contain the disorder of mass sequence of amino acids and the fluctuations of the coupling constant, force constant and dipole- dipole interaction constant and ground state energy of the proteins, designating the features of its structure and interactions between the particles in it. However, the soliton disperses in the cases of higher temperature of 325 K and larger structure disorders. The numerical results show that, the new soliton is very robust against; the influences of the thermal perturbation kind structure disorders at biological temperature 300 K, its lifetime and critical temperature are at least 300 ps at 300 K and 320 K, respectively. These results are also consistent with analytical data.
关键词:
protein molecules;soliton;bio-energy transport;thermal stability;fluctuation;characteristic parameter;davydov soliton;living systems;finite-temperature;improved model;quantum;dynamics;lifetime;spectra;excitation;crystals
杨金瑞
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余尚先
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顾江楠
高分子材料科学与工程
通过对resol(羟甲基酚化合物和低分子量羟甲基酚树脂)DEPT135图谱的分析讨论,得到一系列计算resol微细结构参数的经验公式.根据DEPT135图谱可判断是否发生缩聚反应,根据经验公式可计算酚单体各个活性点参与反应百分率或酚羟基导入率、不同类型缩聚所占百分率及低分子量羟甲基酚树脂的平均核体数.
关键词:
羟甲基酚化合物
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羟甲基酚树脂
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DEPT135
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结构参数
Communications in Theoretical Physics
With the strong-field scheme and cubic bases, the complete d(3) energy matrix in a tetragonally distorted cubic-field has been constructed. By diagonalizing this matrix, the energy spectra of SrTiO3:Cr3+ and SrTiO3:Mn4+ at normal pressure and various temperatures have been calculated. Correspondingly, the FORTRAN program calculating the g factor of the ground state has been worked out. By using the program and the wave function obtained from diagonalizing the complete energy matrix, the g factors of the ground state of SrTiO3:Cr3+ and SrTiO3:Mn4+ at normal pressure and room temperature have been evaluated. The calculated results are in good agreement with the optical spectral and EPR experimental data. The comparison and analysis of the results of two crystals have been made. It is demonstrated that the covalency of the bonding between Mn4+ and ligands (O2-) in SrTiO3:Mn4+ is stronger than the one of the bonding between Cr3+ and ligands (O2-) in SrTiO3:Cr3+. It is shown that the obtained wavefunctions and values of parameters are reasonable.
关键词:
crystal fields;energy spectrum;optical properties;g factors;covalency;ruby
Advanced Materials
Popularization of portable electronics and electric vehicles worldwide stimulates the development of energy storage devices, such as batteries and supercapacitors, toward higher power density and energy density, which significantly depends upon the advancement of new materials used in these devices. Moreover, energy storage materials play a key role in efficient, clean, and versatile use of energy, and are crucial for the exploitation of renewable energy. Therefore, energy storage materials cover a wide range of materials and have been receiving intensive attention from research and development to industrialization. In this Review, firstly a general introduction is given to several typical energy storage systems, including thermal, mechanical, electromagnetic, hydrogen, and electrochemical energy storage. Then the current status of high-performance hydrogen storage materials for on-board applications and electrochemical energy storage materials for lithium-ion batteries and supercapacitors is introduced in detail. The strategies for developing these advanced energy storage materials, including nanostructuring nano-/microcombination, hybridization, pore-structure control, configuration design, surface modification, and composition optimization, are discussed. Finally, the future trends and prospects in the development of advanced energy storage materials are highlighted.
关键词:
lithium-ion batteries;carbon nanotube electrodes;enhanced hydrogen;storage;metal-organic frameworks;double-layer capacitors;n-h system;carbide-derived carbons;ammonia borane dehydrogenation;ordered;mesoporous carbons;high-rate performance
Communications in Theoretical Physics
The local impurity-vibration modes (especially, the low-frequency one) of SrTiO3:Cr3+ cause a very large R-line blue-shift; while the Raman term, neighbor-level term and optical-branch term relevant to the lattice vibration cause small red shifts. The algebraic sum of them gives rise to the observed unusual and large R-line thermal shift (blue-shift) of SrTiO3:Cr3+. By taking into account all the irreducible representations and their components in the electron-phonon interaction (EPI) as well as all the levels and the admixtures of basic wavefunctions within d(3) electronic configuration, the values of the parameters in the expressions of thermal shift (TS) from EPI for the ground level, R level and R line of SrTiO3:Cr3+ have been evaluated; the R-line TS and various contributions to it have been calculated in two temperature ranges (30 K less than or equal to T less than or equal to 80 K and 130 K less than or equal to T less than or equal to 300 K). The contribution to R-line TS from thermal expansion has been approximately neglected in this work. Furthermore, the improvement on simplified approximation of adopting a single low-frequency impurity-mode and neglecting its hardening in low-temperature region has been made.
关键词:
crystal fields;optical properties;thermal shift;electron-phonon;interaction;impurity modes;softening and hardening
