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Comparative study using mS and XRD of Fe_(80)Al_(20) alloy produced by mechanical alloying

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Science China(Physics,mechanics & Astronomy) 2013年第8期56卷 1504-1507页

作者： HADEF F. OTmANI A. GRENèCHE j.m. Laboratoire de Recherche sur la Physico-Chimie des Surfaces et Interfaces LRPCSIUniversité 20 Ao t 1955BP 26Route d'El-HaddaiekSkikda 21000Algérie LUNAm Université du MaineInstitut des Molécules et Matériaux du MansIMMM UMR CNRS 628372085 Le MansFrance

An X-ray diffraction and 57Fe mOssbauer effect study of mechanically alloyed Fe80Al20 is presented. X-ray measurements indicate that the disordered bcc α-Fe（A1） solid solution was formed after 2 h of milling, while the analysis of mrssbauer spectra suggested that total dissolution of aluminium is achieved after 10 h of milling. These differences can be attributed to：（i） rapid nanocrystallization of aluminium and/or （ii） small particles with small amounts of aluminium cannot be detected by the X-ray diffraction technique.

关键词： nanostructured materials Fe-AI alloys mechanical alloying X-ray diffraction m6ssbauer spectrometry

ON THE DYNAmIC CHARACTERISTICS OF mOULD-FILLING UNDER COUNTERGRAVITY

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Acta metallurgica Sinica(English Letters) 1997年第5期10卷 409-414页

作者： Zeng, j.m. Gu, H. Zhou, Y.H. Guangxi Univ Nanning China

In this paper, the mathematical models for mould-filling under countergravity are derived on the basis of the principle of momentum. Dynamic processes of mould-filling are observed on a perspex model by means of high speed photography. The results indicate that the mould-filling under countergravity can be described by the second order nonlinear differential equations characterized by damping oscillations. The velocity oscillations amplify as the pressuring speed increases if the pressure differential functions are of the same type. On the other hand, if the functions are of different type, then the velocity oscillations depend upon whether the functions progressively increase or decrease. Velocity oscillations can be diminished dramatically by increasing the local damping within the gating system.

关键词： casting mould-filling dynamics

On Evolution Algebras

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Algebra Colloquium 2014年第2期21卷 331-342页

作者： j.m. Casas m. Ladra B.A. Omirov U.A. Rozikov Department of Applied mathematics E. U.I.T. Forestal Pontevedra University of Vigo 36005 Spain Department of Algebra University of Santiago de Compostela 15782 Spain Institute of mathematics Tashkent 100125 Uzbekistan

The structural constants of an evolution algebra are given by a quadratic matrix. In this work we establish an equivalence between nil, right nilpotent evolution algebras and evolution algebras defined by upper triangular matrices. The classification of 2-dimensional complex evolution algebras is obtained. For an evolution algebra with a special form of the matrix, we describe all its isomorphisms and their compositions. We construct an algorithm running under mathematica which decides if two finite dimensional evolution algebras are isomorphic.

关键词： evolution algebra nil algebra right nilpotent algebra group of endomor-phisms classification

Ferritin acts as a target site for the snowdrop lectin （GNA） in the midgut of the cotton leafworm Spodoptera littoralis

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Insect Science 2008年第6期15卷 513-519页

作者： Amin Sadeghi Guy Smagghe Paul Proost Els j.m. Van Damme Laboratory of Agrozoology Department of Crop Protection Laboratory of Biochemistry and Glycobiology Department of Molecular Biotechnology Faculty of Bioscience Engineering Ghent University Ghent Rega Institute Laboratory of Molecular Immunology Kathofieke Universiteit Leuven Minderbroedersstraat 10 B-3000 Leuven Belgium

The snowdrop lectin GNA （Galanthus nivalis agglutinin） has been shown to possess insecticidal activity to a range of economically important insect pests. However, the precise mechanism of insecticidal action of GNA against insects remains unknown. In this investigation, we attempted to purify and identify receptor（s） responsible for binding of GNA in the larval midgut of a major lepidopteran pest （the cotton leafworm, Spodoptera littoralis） to better understand its mode of action. Therefore, cytoplasmic as well as membrane proteins from 800 larval midguts were chromatographed on a column with immobilized GNA. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the proteins eluted from the GNA column followed by sequencing of the GNA-binding proteins and BLAST analyses revealed that the N-terminal sequences of a 24 kDa polypeptide purified from the cytoplasmic and membrane protein fraction revealed sequence similarity to sequences encoding heavy chain homologs of ferritin from manduca sexta （76% sequence identity）, Calpodes ethlius （80% sequence identity） and Bombyx mori （61% sequence identity）. Furthermore, the N-terminal sequence of a 31 kDa polypeptide from the membrane protein fraction showed sequence similarity to a light chain homolog of ferritin from manduca sexta （88% sequence identity）.

关键词： ferritin Galanthus nivalis agglutinin GNA Lepidoptera midgut receptors Spodoptera littoralis

Symbol detection based on Voronoi surfaces with emphasis on superposition modulation

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Digital Communications and Networks 2017年第3期3卷 141-149页

作者： martin Damrath Peter Adam Hoeher Gilbert j.m. Forkel Institute of Electrical and Information Engineering Faculty of Engineering University of Kiel Kaiserstr. 2 24143 Kiel Germany

A challenging task when applying high-order digital modulation schemes is the complexity of the detector. Particularly, the complexity of the optimal a posteriori probability （APP） detector increases exponentially with respect to the number of bits per data symbol. This statement is also true for the max-Log-APP detector, which is a common simplification of the APP detector. Thus it is important to design new detection algorithms which combine a sufficient performance with low complexity. In this contribution, a detection algorithm for two- dimensional digital modulation schemes which cannot be split-up into real and imaginary parts （like phase shift keying and phase-shifted snperposition modulation （PSm）） is proposed with emphasis on PSm with equal power allocation. This algorithm exploits the relationship between max-Log-APP detection and a Voronoi diagram to determine planar surfaces of the soft outputs over the entire range of detector input values. As opposed to state-of-the-art detectors based on Voronoi surfaces, a priori information is taken into account, enabling iterative processing. Since the algorithm achieves max-Log-APP performance, even in the presence of a priori information, this implies a great potential for complexity reduction compared to the classical APP detection.

关键词： Digital modulation Demodulation Detection algorithms Linear approximation

Piecewise linear detection for direct superposition modulation

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Digital Communications and Networks 2018年第2期4卷 98-105页

作者： martin Damrath Peter Adam Hoeher Gilbert j.m. Forkel Institute of Electrical and Information Engineering Faculty of Engineering University of Kiel Kaiserstr. 2 24143 Kiel Germany

Considering high-order digital modulation schemes, the bottleneck in consumer products is the detector rather than the modulator. The complexity of the optimal a posteriori probability （APP） detector increases exponentially with respect to the number of modulated bits per data symbol. Thus, it is necessary to develop low-complexity detection algorithms with an APP-like performance, especially when performing iterative detection, for example in conjunction with bit interleaved coded modulation. We show that a special case of superposition modulation, dubbed Direct Superposition modulation （DSm）, is particularly suitable for complexity reduction at the receiver side. As opposed to square QAm, DSm achieves capacity without active signal shaping. The main contribution is a low-cost detection algorithm for DSm, which enables iterative detection by taking a priori information into account. This algorithm exploits the approximate piecewise linear behavior of the soft outputs of an APP detector over the entire range of detector input values. A theoretical analysis and simulation results demonstrate that at least max-log APP performance can be reached, while the complexity is significantly reduced compared to classical APP detection.

关键词： Digital modulation Demodulation Detection algorithms Linear approximation

Design of Agents Interacting with Immunoregulating Proteins:Potential Inhibitors of the Phenylpyruvate Tautomerase Activity Catalysed by macrophage migration Inhibitory Factor (mIF)

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Chinese journal of Chemistry 2003年第10期21卷 1256-1262页

作者： CARPY Alain j.m. HAASBROEK P.P. OLIVER D.W. PTC-UmR 5472 CNRS Department of Pharmacy and PharmacologyPharmacology Faculty of Health Science University of Bordeaux ITalence France University of Witwatersrand JohannesburgSouth AfricaPotchefstroom University for CHE PotchefstroomSouth Africa

The macrophage migration inhibitory factor has been implicated in a number ofimmune and inflammatory processes. mIF presents particular opportunities for drug design anddevelopment with potential therapeutic applications. Drug design strategies taking intoconsideration of specific stereochemical and tautomeric requirements in the interaction of mIF withsubstrates and inhibitors allow several novel structures to be designed. Our investigationssuccessfully explored the tautomeric and stereochemical aspects of new compounds of the2-phenylpyruvic acid type, both experimentally, through synthesis and structural investigations andcomputationally, through molecular mechanics and quantum mechanics calculations.

关键词： macrophage migration inhibitory factor phenylpyru-vate tautomerase activity azlactone phenylpyruvic acid derivative

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彼得·潘

main α relaxation and slow β relaxation processes in a La30Ce30Al15Co25 metallic glass

作者： (英)j.m. 巴里(j.m. Barrie)

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journal of materials Science & Technology 2019年第6期35卷 982-986页

作者： j.C. Qiao Y.H. Chen R. Casalini j.m. Pelletier Y. Yao School of mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an 710072 China Chemistry Division Naval Research Laboratory Code 6120 Washington DC 20375-5342 United States Universite de Lyon MATEIS UMR CNRS5510 Bat. B. Pascal INSA-Lyon F-69621 Villeurbanne cedex France

Dynamic relaxation processes are fundamental to understand the mechanical and physical properties of metallic glasses. In the current work, mechanical relaxations in a La30Ce30Al15Co25 bulk metallic glass were probed by dynamic mechanical analysis. In contrast to many metallic glasses, La30Ce30Al15Co25 metallic glass shows a pronounced slow β relaxation peak. Physical aging below the glass transition temperature Tgleads to an increase of the apparent activation energy and a decrease of the slow β relaxation magnitude. The correlation between the slow β relaxation and the main α relaxation is discussed.

关键词： mechanical relaxation Dynamic mechanical relaxation α Relaxation β relaxation Physical aging