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Joint Wavelet-Fractional Fourier Transform

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Chinese Physics Letters 2016年第11期33卷 18-21页

作者：宋军何锐袁好周军范洪义 department of material and Chemical eng.neering West Anhui University department of material Science and eng.neering University of Science and Technology of China

Based on Dirac＇s representation theory and the technique of integration within an ordered product of operators, we put forward the joint wavelet-fractional Fourier transform in the context of quantum mechanics. Its corresponding transformation operator is found and the normally ordered form is deduced. This kind of transformation may be applied to analyzing and identifying quantum states.

关键词： of or on is in Joint Wavelet-Fractional Fourier Transform

Kinetics for Formation of TbFe_2 in the Ca-Tb_4O_7-Fe System

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Journal of Rare Earths 2003年第2期21卷 132-134页

作者：郭广思王广太隋智通 department of material Science and eng.neering Shenyang Institute of Technology College of material and Metallurgy Northeastern University

The pure TbFe 2 is a sort of intermetallic compound to produce (TbDy)Fe 2. It has important practical meanings to develop a new method for producing pure TbFe 2 directly from Tb 4O 7 with low cost and non pollution. Based on our previous thermodynamic study on the production of TbFe 2 by reduction diffusion in Ca Tb 4O 7 Fe system, kinetics has been further studied in this work. It is confirmed that the product is TbFe 2 by means of XRD. The contracting core model is applied. The reactions are found to be diffusion controlled. The apparent activation energy of TbFe 2 is 39 kJ·mol -1 .

关键词： inorganic chemistry Ca Tb 4O 7 Fe system TbFe 2 contracting core model rare earths

Micellization,Interaction and Microenvironment in the Mixed Solution of Pluronics and Surfynol 104 with Nuclear Magnetic Resonance

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过程工程学报 2009年第4期9卷 722-730页

作者：宋寒郭晨马俊鹤向俊峰唐亚林 P.Bahadur 刘会洲 Lab.Sep.Sci.& eng. State Key Lab.Biochem.Eng.Inst.Process Eng.CAS NIH Bethesda Maryland Analysis & Measurement Center Inst.Chem.CAS department of Chemistry V.N.South Gujarat University

The micellization,intermolecular interaction and microenvironment of molecular segments in the mixed aqueous solution of PEO-PPO-PEO triblock copolymer(Pluronic F88,P84 and P123) and Surfynol 104(S104) were studied by nuclear magnetic resonance *** results showed that the addition of S104 decreased the critical micellization temperature of *** its concentration was 0.5 g/L,the most reduction was up to more than 10℃ for F88,which was most hydrophilic in the selected *** reduction was caused by the hydrophobic interaction between S104 molecules and PPO *** addition of S104 enhanced the hydration of PEO segments most obviously for *** S104 slightly increased the hydration of PPO segments before the micellization,but obviously decreased their hydration after micellization,which was attributed to the hydrophobic interaction mentioned above and temperature *** effect was most observable for F88.

关键词：乙烯水化作用浓度核磁共振

Maximizing biomass utilization: An integrated strategy for coproducing multiple chemicals

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Journal of Energy Chemistry 2025年第1期100卷 180-191页

作者： Byeongchan Ahn Sua Jo Jonggeol Na J.Jay Liu Young-Ju Kim Wangyun Won department of Chemical and Biological eng.neering Korea University department of Chemical eng.neering (Integrated process) Kyung Hee University department of Chemical eng.neering and materials Science Ewha Womans University department of Chemical eng.neering Pukyong National University Resources eng.neering Plant Research department Korea Institute of Geoscience and Mineral Resources

Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol（1,6-HDO） with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments（LCAs）.Strategy A was found to be the most favorable both economically（USRDSCHARDOLLAR3,402/ton） and environmentally（-26.9 kg CO2eq.）. This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.

关键词： Biorefinery Carbon mitigation Climate change Global warming Lignin utilization Bioeconomy

Effects of Annealing Temperature on the Electrical Conductivity and Mechanical Property of Cu-Te Alloys

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Journal of Wuhan University of Technology(materials Science) 2007年第1期22卷 88-90页

作者：朱达川 Metallic material department College of Material Science and Engineering Sichuan University

The effects of annealing temperatre on the electrical conducitivity and mechanical property of Cu-Te alloys were studied via an AG-10TA electronic universal machine, an SB2230 digital electric bridge, SEM, EDS and XPS. The results show the electrical conductivity increases while the tensile streng.h fluctuates when the annealing temperature becomes higher because the recrystallization occurs during the annealing process, leading to the density of dislocation decreasing, grain size growing up, but the second phase precipitating sufficiently and simultaneously.

关键词： Cu-Te alloys annealing temperature recrystallization

Fabrication and its characteristics of low-temperature polycrystalline silicon thin films

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Science China(Technological Sciences) 2009年第1期52卷 260-263页

作者： LASSAUT J department of material Sciences of ENSIL

In order to reduce the cost of solar cells or flat-panel display, it is very important to synthesis polycrystalline silicon films on low cost substrate such as glass at low temperature. In this work, electron cyclotron resonance (ECR) plasma enhanced chemical vapor deposition (PECVD) system was successfully applied to synthesize poly-Si thin-film on common glass substrate using H2 as the plasma source and SiH4 (Ar:SiH4=19:1) as the precursor gas at low temperature. Since the multicusp cavity-coupling ECR plasma source was adopted to provide active precursors, the growth temperature decreased to lower than 200°C. In the plasma, the electron temperatures kT e are ～2–3 eV and the ion temperatures kT i≤1 eV. This leads to non-remarkable ion impacts during the film deposition. The characteristic of poly-Si films was investigated. It was shown that the crystalline fraction X c of the films can be up to 90% even deposit at room temperature, and the film was (220) preferably oriented. The growth behaviors of the film between the interface of glass and Si films were also discussed in detail.

关键词： ECR-PECVD poly silicon low temperature glass substrate

Electrochemical Behavior of La-doped LiFePO4/C Cathode materials for Lithium Ion Batteries

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过程工程学报 2015年第3期15卷 511-517页

作者：王山杨海涛张立博许洪亮石丽丽 National Key Lab. Multi-phase Complex Systems Inst. Process Eng. Chinese Academy of Sciences Beijing Key Lab. Environ. Sci. & eng. Sch. Chem. Eng. & Environ. Beijing Institute of Technology

Alien atom was used to obtain a series of Li Fe1-xLaxPO4/C(x=0,0.002,0.005,0.01,0.015)cathode materials with the aim of investigating the influence of participation of La on the electrochemical behavior of Li Fe PO4/*** of X-ray diffractometer,scanning electron microscope equipped with energy dispersive spectrometer and high resolution transmission electron microscope was *** results show that all the La-doped Li Fe PO4/C samples are olivine type crystals,La ion is sufficiently introduced into the network,and every element is well homogeneously *** are many pore spaces on the surface of *** content of carbon in the prepared cathode materials remains 13.6%calculated by TGA/DTA curves,and the particles are wrapped by a uniformly and continuous carbon layer with the thickness of about 2 ***,the content of Fe2P also keeps the same basically in all the cathode materials as a result of the similar ratio(2.35)of peak intensity at 36.5o and 37.1o from *** increasing trend is most pronounced at doped 0.005which presents the highest initial discharge capacity of 163 mA-h/g,lowest charge transfer resistance of 5.52-,superior diffuse ability of lithium ion(10-11 cm2/s)and the best capacity retention current rate of about 93%after 50 cycles at 0.1 C.

关键词： LiFePO4 cathode material lanthanum doping lithium ion battery

A new theorem relating quantum tomogram to the Fresnel operator

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Chinese Physics B 2011年第6期20卷 23-28页

作者：谢传梅范洪义 College of Physics & material Science Anhui University department of material Science and eng.neering University of Science and Technology of China

According to Fan-Hu’s formalism (Fan Hong-Yi and Hu Li-Yun 2009 Opt. Commun. 282 3734) that the tomogram of quantum states can be considered as the module-square of the state wave function in the intermediate coordinate-momentum representation which is just the eigenvector of the Fresnel quadrature phase, we derive a new theorem for calculating quantum tomogram of density operator, i.e., the tomogram of a density operator ρ is equal to the marginal integration of the classical Weyl correspondence function of F+ρF , where F is the Fresnel operator. Applications of this theorem to evaluating the tomogram of optical chaotic field and squeezed chaotic optical field are presented.

关键词： quantum tomogram Fresnel operator Weyl correspondence

New theorem relating two-mode entangled tomography to two-mode Fresnel operator

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Chinese Physics B 2012年第1期21卷 62-67页

作者：谢传梅范洪义 College of Physics & material Science Anhui University department of material Science and eng.neering University of Science and Technology of China

Based on the Fan-Hu’s formalism, i.e., the tomogram of two-mode quantum states can be considered as the module square of the states’ wave function in the intermediate representation, which is just the eigenvector of the Fresnel quadrature phase, we derive a new theorem for calculating the quantum tomogram of two-mode density operators, i.e., the tomogram of a two-mode density operator is equal to the marginal integration of the classical Weyl correspondence function of F?2ρF2, where F2is the two-mode Fresnel operator. An application of the theorem in evaluating the tomogram of an optical chaotic field is also presented.

关键词： two-mode quantum tomogram two-mode Fresnel operator Weyl correspondence