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Calculation of the Specific heats for the Ⅱ—Ⅲ and Ⅱ—Ⅳ Phase transitions in Nh4I

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Chinese Physics Letters 2003年第1期20卷 35-38页

作者： h.Yurtseven h.Kaya Departmentofphysics IstanbulTechnicalUniversityMaslakIstanbulTurkey

This study gives our calculation for the specific heats CVI due to an Ising model using the observed CP data for the II-III and II-IV phase transitions in Nh4I. By fitting to the CP data we determine the values of the critical exponent for the pressure of 0.14 GPa (II-III phase transition) and for the pressures of 0.75, 1.35 and 1.97 GPa (II-IV phase transition) in Nh4I. Our exponent values are close to the predicted values of the specific heat in a three-dimensional Ising model. Our calculated CVI are in good agreement with the experimental CP for Nh4I in most cases.

关键词： Specific heat

A good example of high-energy radiation delay event

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Chinese Science Bulletin 1997年第4期42卷 313-315页

作者： GAN Weiqun and Rieger erich1 Purple Mountain Observatory, Nanjing 210008, China 2. Max-Planck Institute of Extraterrestrial Physics, Garching 85740,Germany Purple Mountain Observatory Nanjing China Max-Planck Institute of Extraterrestrial Physics Garching Germany

ThE delay of high-energy radiation of solar flares can be divided into two types: one is the energy-dependent delay in the hard X-ray regime, the other is the delay between the hard X-rays and instantaneous γ-ray line (GRL) emissions. Both types have different physical meanings. The former reflects the difference in acceleration or transportation of energetic electrons with various energies, while the latter reflects such a difference between the energetic electrons

关键词： sun. flare X-ray γ-ray.

An inverted triplesalen ligand by a convergent synthesis and its influence on trinuclear FeXII3 complexes

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中国科学：化学 2012年第6期42卷 897-900页

作者： Bastian FELDSChER erich KRICKEMEYER Marc MOSELAGE hubert ThEIL Veronika hOEKE Yvonne KAISER Anja STAMMLER hartmut BGGE Thorsten GLASER Lehrstuhl f黵 Anorganische Chemie I Fakult鋞 f黵 Chemie Universit鋞 Bielefeld Universit鋞sstr. 25 D-33615 Bielefeld Germany

The inverted triplesalen ligand h6feldMehas been synthesized from 2,4,6-triformyl-phloroglucinol and a ketimine salen half-unit in a convergent synthesis. NMR, IR, and UV-vis spectroscopy reveal that this ligand is not in the O-protonated tautomer but in the N-protonated tautomer with substantial heteroradialene contribution. This ligand and the conventional triplesalen ligand h6talent-Bu2 have been used to synthesize the trinuclear FeⅢcomplexes [(feldMe)(FeCl)3] and [(talent-Bu2)(FeCl)3], respectively. The molecular structures of these complexes were obtained by single-crystal X-ray diffraction. Two trinuclear FeⅢcomplexes of [(feldMe)(FeCl)3] dimerize via two Fe-phenolate bonds, whereas due to steric hindrance no dimerization is observed for [(talent-Bu2)(FeCl)3]. The structural data also reveal some heteroradialene contribution in the trinuclear complexes. Whereas UV-vis and M??bauer spectroscopy are not suitable to distinguish between the two complexes, FT-IR spectra show characteristic features due to the different substitution patterns of the conventional and the inverted triplesalen ligands. Another handle is provided by electrochemistry. Whereas both complexes exhibit an irreversible oxidation wave (0.94 V vs. Fc+/Fc for [(feldMe)(FeCl)3] and 0.84 V vs. Fc+/Fc for [(talent-Bu2)(FeCl)3]), which is assigned to the oxidation of the central backbone, higher potential oxidations are reversible for [(talent-Bu2)(FeCl)3]) but irreversible for [(feldMe)(FeCl)3]. This is attributed to the reversible oxidation of the terminal phenolates in the di-tert-butyl substituted [(talent-Bu2)(FeCl)3] in contrast to the mono-methyl-substituted phenolates in [(feldMe)(FeCl)3]. The magnetic properties of [(talent-Bu2)(FeCl)3] reveal a very small ferromagnetic coupling with significant zero-field splitting of the FeⅢS = 5/2 ions. In contrast, the dimerization of two trinuclear complexes in [(feldMe)(FeCl)3] results in antiferromagnetic interactions between the two phenolate-bridged

关键词：三核配合物合成收敛反铁磁相互作用复合物单晶X-射线衍射紫外可见光谱铁配合物

Mechanical and microstructural characterization of Al7075/SiC nanocomposites fabricated by dynamic compaction

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 295-303页

作者： A.Atrian G.h.Majzoobi M.h.Enayati h.Bakhtiari Mechanical Engineering Department Bu-Ali Sina University Department of Materials Engineering Isfahan University of Technology

This paper describes the synthesis of Al7075 metal matrix composites reinforced with SiC, and the characterization of their microstructure and mechanical behavior. The mechanically milled Al7075 micron-sized powder and SiC nanoparticles are dynamically compacted using a drop hammer device. This compaction is performed at different temperatures and for various volume fractions of SiC nanoparticles. The relative density is directly related to the compaction temperature rise and indirectly related to the content of SiC nanoparticle reinforcement, respectively. Furthermore, increasing the amount of SiC nanoparticles improves the strength, stiffness, and hardness of the compacted specimens. The increase in hardness and strength may be attributed to the inherent hardness of the nanoparticles, and other phenomena such as thermal mismatch and crack shielding. Nevertheless, clustering of the nanoparticles at aluminum particle boundaries make these regions become a source of concentrated stress, which reduces the load carrying capacity of the compacted nanocomposite.

关键词： nanocomposites metallic matrix composites silicon carbide nanoparticles compaction

Solid-State Interfacial Reaction between Eutectic Au-Ge Solder and Cu/Ni(P)/Au Metalized Ceramic Substrate and Its Suppression

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Journal of Materials Science & Technology 2015年第5期31卷 445-452页

作者： F.Q.Lang h.Yamaguchi h.Nakagawa h.Sato Advanced Power Electronics Research Center(ADPERC) National Institute of Advanced Industrial Science and Technology(AIST).Central 21-1-1UmezonoTsukubaIbaraki 305-8568.Japan

Eutectic Au-12 Ge solder was employed to bond the SiC power devices to a Si3N4/Cu/Ni（P）/Au multilayered *** high-temperature reliability of the bond was investigated in detail at 200,250,300 and 330 ℃,*** and Ni5Ge3intermetallic compounds（IMCs） were identified at the Au-12Ge/Ni（P） interface by micro X-ray diffraction（μXRD） and scanning electron microscopy（SEM）equipped with energy dispersive X-ray analysis（EDX）.The growth of the Ni-Ge IMCs was dominated by Ni5Ge3layer,which formed at the Ni5Ge3/NiGe interface by outward diffusion of Ni from the Ni（P） *** activation energy of the total Ni-Ge IMCs growth was 66 kJ/*** shear strength of the bond was tested at both 25 ℃ and the aging temperatures,*** shear strength decreased slightly after aging at 200 and 250 ℃.The shear strength tested at 250 ℃ was 46 MPa after aging at 250 ℃ for 3000 *** shear strength aged at 300 and 330 ℃ rapidly decreased with aging time due to the rapid growth of the *** slow down the interfacial reaction between the high temperature solder and the Ni（P）layer,an approximately 200 nm-thick Ta/TaN/Ta new diffusion barrier（DB） was deposited on the *** by transmission electron microscopy（TEM） equipped with EDX,reveals that the Ta/TaN/Ta DB was bonded well to the Ni（P） layer and the *** temperature storage test at 330 ℃ for1500 h reveals that the bond of the SiC devices maintained its high shear strength of approximately56 MPa without *** new DB effectively suppressed the interfacial reaction between the Au-12 Ge solder and the Ni（P） layer of the substrate.

关键词： high-temperature solder Interfacial reaction Activ

A modified averaging scheme with application to the secondary hopf bifurcation of a delayed van der Pol oscillator

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Acta Mechanica Sinica 2008年第4期24卷 449-454页

作者： Z.h.Wang h.Y.hu Institute of Sciences PLA University of Science and Technology Nanjing 211101 China Institute of Vibration Engineering Research Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

In this paper, a modified averaging scheme is presented for a class of time-delayed vibration systems with slow variables. The new scheme is a combination of the averaging techniques proposed by hale and by Lehman and Weibel, respectively. The averaged equation obtained from the modified scheme is simple enough but it retains the required information for the local nonlinear dynamics around an equilibrium. As an application of the present method, the delay value for which a secondary hopf bifurcation occurs is successfully located for a delayed van der Pol oscillator.

关键词： Time delay ·Secondary hopf bifurcation·The averaging technique van der Pol oscillator

Numerical Solution of the Asymmetric Water Impact of A Wedge in Three Degrees of Freedom

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China Ocean Engineering 2013年第3期27卷 313-322页

作者： h. Ghazizade-Ahsaee A. h. Nikseresht Faculty of Mechanical & Aerospace Engineering Shiraz University of Technology

Impact problems associated with water entry have important applications in various aspects of naval architecture and ocean engineering. Estimation of hydrodynamic impact forces especially during the first instances after the impact is very important and is of interest. Since the estimation of hydrodynamic impact load plays an important role in safe design and also in evaluation of structural weight and costs, it is better to use a reliable and accurate prediction method instead of a simple estimation resulted by analyzing methods. In landing of flying boats, some phenomena such as weather conditions and strong winds can cause asymmetric instead of symmetric descent. In this paper, a numerical simulation of the asymmetric impact of a wedge, as the step of a flying boat, considering dynamic equations in two-phase flow is taken into account. The dynamic motion of the wedge in two-phase flow is solved based on finite volume method with volume of fluid （VOF） scheme considering dynamic equations. Then the effects of different angles of impact and water depth on the velocity change and slamming forces in an asymmetric impact are investigated. The comparison between the simulation results and experimental data verifies the accuracy of the method applied in the present study.

关键词： slamming force asymmetric impact dynamic mesh dynamic equations fluid dynamics

GLOBAL OPTIMIZATION OF ThE DIFFERENCE OF TWO INCREASING PLUS-CONVEX-ALONG-RAYS FUNCTIONS

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Acta Mathematica Scientia 2020年第6期40卷 1849-1873页

作者： h.ShAhRIARIPOUR h.MOhEBI Department of Mathematics Graduate University of Advanced TechnologyKermanIran Department of Mathematics and Mahani Mathematical Research Center Shahid Bahonar University of KermanP.O.Box:76169133Postal Code:***KermanIran

The theory of increasing and convex-along-rays(ICAR)functions defined on a convex cone in a real locally convex topological vector space X was already well *** this paper,we first examine abstract convexity of increasing plus-convex-along-rays(IPCAR)functions defined on a real normed linear space *** also study,for this class of functions,some concepts of abstract convexity,such as support sets and ***,as an application,we characterize the maximal elements of the support set of strictly IPCAR functions and give optimality conditions for the global minimum of the difference between two IPCAR functions.

关键词： increasing plus-convex-along-rays function support set maximal element global minimum DC-function

Thermal Therapy in Patients Suffering from Non-Specific Chronic Low Back Pain—A Systematic Review

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International Journal of Clinical Medicine 2018年第4期9卷 294-314页

作者： Selina Wittenwiler Rahel Stoop erich hohenauer Ron Clijsen Research Rehabilitation 2rLab Department of Business Economics Health and Social Care University of Applied Sciences and Arts of Southern Switzerland Landquart Switzerland ThIM University of Applied Sciences Landquart Switzerland Department of Movement and Sport Sciences Vrije Universiteit Brussel Brussels Belgium

Thermal therapy is frequently used as an adjunct to treatment in patients suffering from chronic low back pain. It is also an inherent part of patients’ self-administered pain treatment. This review aims to update the evidence for thermal therapy treatments in non-specific chronic low back pain patients and to rate the methodological quality of the corresponding clinical trials. Previous studies have reported contradictory evidence for the effectiveness of thermal therapy. An electronic search on MEDLINE (PubMed), PEDro, CENTRAL and CINhAL databases was conducted between May 2016 and February 2018. Clinical trials comparing local thermal therapy to conservative or no treatment were assessed for eligibility. Pain, physical function and global health were defined as outcome parameters. A total of n = 9 studies met the inclusion criteria. All of them applied an electrophysical agent as the thermal treatment: continuous ultrasound (n = 6), short-wave diathermy (n = 2), microwave diathermy (n = 1). Out of the n = 6 studies on ultrasound treatment, n = 2 reported significant within and between-group results for pain reduction after 4 to 6 weeks of treatment. Both short-wave diathermy studies demonstrated significant between-group results for pain reduction after 3 weeks of treatment. Contradictory results for all other observed outcome parameters were reported regardless of the intervention. Moreover, significant within-group results for the control groups questioned the effectiveness of the intervention treatments. Therefore, the effect of thermal therapy, (electrophysical agents), is not superior to any control treatment except for ultrasound treatment on short-term pain reduction.

关键词： Electrophysical Agents heat Application Pain Reduction Physical Function Non-Specific Chronic Low Back Pain Thermal Therapy