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Precipitation morphology and kinetics of T-Al6Mg11Zn11 intermetallic phase in Al-Mg-Zn ternary alloys

INTERMETALLICS 2021年 139卷

作者： Takata, Naoki Takagi, Rikito Li, Ruoqi Ishii, Hiroki Suzuki, Asuka Kobashi, Makoto Nagoya Univ Grad Sch Engn Dept Mat Proc Engn Chikusa Ku Furo Cho Nagoya Aichi 4648603 Japan

This study was undertaken to understand the fundamentals of T-Al6Mg11Zn11 intermetallic phase precipitation in heat-resistant Al-Mg-Zn ternary alloys, with the goal of further strength improvements. The thermodynamic assessment involved three alloy compositions, Al-4Mg-4.5Zn, Al-5Mg-3.5Zn, and Al-7Mg-1.5Zn (at%), with the T phase in a fixed fraction (approximately 6-7.5%) in equilibrium with the alpha-Al phase at 300 degrees C. The alloy compositions were set on different tie-lines between the alpha-Al and T phases in the two-phase region, resulting in varied compositions of each phase. In the three experimental alloys aged at 300 degrees C, the T phase precipitated on the grain boundaries of the alpha-Al matrix, and granular precipitates were homogeneously dispersed intragranularly. There was no significant difference in the precipitation morphology. It was demonstrated that the lattice parameters of the T and alpha-Al phases could be controlled based on the alloy composition and applied heat treatments. However, the lattice parameters have no significant effect on the precipitation morphologies of the thermodynamically stable T phase in the Al-Mg-Zn ternary alloys. The Zn-rich Al-4Mg-4.5Zn alloy exhibited a pronounced softening behavior after 10 h of aging due to the enhanced coarsening of precipitates in the alpha-Al matrix. The thermal instability of the precipitates was responsible for the transformation sequence from the initially formed metastable phases (eta-Zn2Mg associated phases) to the stable T phase. These results provided a fundamental insight that alloy strengthening by introducing thermodynamically stable intermetallic phases is essential for sustaining the strength of heat-resistant Al-Mg-Zn ternary alloys after long-term treatment at elevated temperatures.

关键词： A intermetallics (aluminides Silicides) B age-hardening Alloy design C heat treatment D microstructure E phase stability Prediction f electron microscopy Transmission G automotive uses Including engines (and other transportation uses)

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Martensitic transformation and elastocaloric effect of Co51.5+xV31.5-xGa17 (x=0.1, 0.2, 0.3) alloys

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INTERMETALLICS 2021年 139卷

作者： He, Jing Wei, Zhiyang Sun, Wen Lu, Xiang Ma, Shengcan Liu, Jian Jiangxi Univ Sci & Technol Fac Mat Met & Chem Jiangxi Key Lab Rare Earth Magnet Mat & Devices Ganzhou 341000 Peoples R China Chinese Acad Sci Ningbo Inst Mat Technol & Engn CAS Key Lab Magnet Mat & Devices Ningbo 315201 Peoples R China Chinese Acad Sci Ningbo Inst Mat Technol & Engn Zhejiang Prov Key Lab Magnet Mat & Applicat Techn Ningbo 315201 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Jiangxi Univ Sci & Technol Coll Rare Earths Ganzhou Key Lab Rare Earth Magnet Funct Mat & Phy Ganzhou 341000 Peoples R China

Co-V-Ga alloy, a newly discovered multifunctional material based on martensitic transformation (MT), has promising application prospects in spintronics and solid-state refrigeration fields. In this work, we investigated the MT behaviors and the elastocaloric effect (eCE) of Co51.5+xV31.5-xGa17 (x = 0.1, 0.2, 0.3) alloys. The alloys undergo a MT from paramagnetic austenite to paramagnetic martensite, accompanying by a large latent heat (about 6-9 J g-1). The MT temperature increases with the increase of the ratio of Co to V. The digital image correlation (DIC) combined with infrared thermography (IR) techniques were utilized to in situ characterize the stress-induced MT and temperature change of the sample. for the sample of x = 0.2, at a testing temperature of 301 K, it heats with a giant adiabatic temperature change up to 13.4 K upon loading, while cools only 2.4 K when stress releasing, showing an irreversible eCE. Raising the test temperature (319, 327 and 333 K) can greatly improve the reversibility of the eCE. Such an asymmetric elastocaloric temperature change at 301 K is closely related to the irreversibility of stress-induced MT, which can be attributed to several factors including the selfcooling effect, heat dissipative mechanism and the valence bond structure of Co-V-Ga alloys.

关键词： A functional alloys B Martensitic transformation Elastocaloric effect f Digital image correlation

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Synthesis and (fluoro)solvatochromism of two 3-styryl-2-pyrazoline derivatives bearing benzoic acid moiety: A spectral, crystallographic and computational study

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JOURNAL Of MOLECULAR LIQUIDS 2021年 331卷

作者： Matiadis, Dimitris Nowak, Katarzyna E. Alexandratou, Eleni Hatzidimitriou, Antonios Sagnou, Marina Papadakis, Raffaello Natl Ctr Sci Res Demokritos Inst Biosci & Applicat Athens 15310 Greece Uppsala Univ Dept Chem Angstrom S-75120 Uppsala Sweden Univ Lodz Fac Biol & Environm Protect Dept Mol Biophys Pomorska St 141-143 PL-90236 Lodz Poland Natl Tech Univ Athens Sch Elect & Comp Engn Lab Biomed Opt & Appl Biophys Zografou Campus Athens 15780 Greece Aristotle Univ Thessaloniki Dept Chem Lab Inorgan Chem Thessaloniki 54124 Greece

In this work we report the synthesis of two fluorescent 2-pyrazoline derivatives exhibiting remarkable (fluoro) solvatochromic behavior. The pyrazolines were synthesized in one step from the corresponding monocarbonyl curcuminoids and 4-hydrazinobenzoic acid in high yield and purity and were fully characterized by means of NMR and fT-IR spectroscopy and HRMS spectrometry. The structure of the novel derivative 2was also characterized by means of X-ray crystallography. Both compounds were studied computationally in the gas phase. Additionally, the effects of solvent polarity on the absorption and fluorescence spectra of these derivatives were investigated in a solvent group consisting of various neat molecular solvents exhibiting hydrogen bond donating (HBD), hydrogen bond accepting (HBA), and/or dipolar behavior. The solvent effects observed were quantified and rationalized by employing suitable multiparametric Linear Solvation Energy Relationships (LSERs) involving dipolarity, HBD-acidity and HBA-basicity terms. The contribution of each of these parameters provided insights on the predominant solute-solvent interactions occurring in solution. Importantly, some differences in the (fluoro)solvatochromic aptitude/behavior were revealed among the derivatives and they were rationalized on the basis of their structural diversity. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Symbol/Abbreviation Meaning/definition A Onsager's Cavity term α HBD-acidity term in KAT equation a Coefficient of α term β HBA-basicity term in KAT equation b Coefficient of β term c 0 Speed of light in vacuum %C( i ) Relaltive contribution of parameter i δ NMR Chemical shift Δ v ~ v ~ abs − v ~ em ε Relative permittivity ε Molar extinction coefficient ε 0 Absolute permittivity of vacuum E f Maximum fluorescence energy E T H Maximum transition energy (high energy feature see Table 5) E T L Maximum transition energy (low energy feature see Table 5) E T (30) Reichardt's polarity scale f ( ε , n ) Solvent Polarity function involved in Lippert–Mataga model (Eq. 6) g ( ε , n ) Solvent Polarity function involved in Bilot–Kawski model (Eq. 10) h Planck's constant HBA Hydrogen Bond Acceptor HBD Hydrogen Bond Donor KAT Kamlet Abboud Taft (Equation) log ε Logarithm of Molar extinction coefficient LSER Linear Solvation Energy Relation μ e Dipole moment of the excited state μ g Dipole moment of the ground state v ~ f fluorescence maximum wavenumber v ~ abs Absorption maximum wavenumber n Refractive index π Dipolarity/polarizability term in KAT equation r Square root of the correlation coefficient R f Retention factor (TLC) r Si Relative contribution of parameter i rse Residual Sum of Squeres σ Hammett's substituent parameter s Coefficient of π term Σ v ~ v ~ em + v ~ ex S ap Aprotic solvent S p Protic Solvent φ ( ε , n ) Solvent Polarity function involved in Bilot–Kawski model (Eq. 9)

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A lattice discrete particle model to simulate the viscoelastic behaviour of macro - synthetic fibre reinforced concrete

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CONSTRUCTION AND BUILDING MATERIALS 2021年 295卷

作者： Del Prete, C. Boumakis, I Wan-Wendner, R. Vorel, J. Buratti, N. Mazzotti, C. Univ Bologna Dept Civil Chem Environm & Mat Engn DICAM Viale Risorgimento 2 I-40136 Bologna Italy Univ Nat Resources & Life Sci Christian Doppler Lab LiCRoFast Peter Jordan Str 82a A-1190 Vienna Austria Univ Ghent Dept Struct Engn & Bldg Mat Technol P Zwijnaa 60 B-9052 Ghent Belgium Czech Tech Univ Fac Civil Engn Thakurova 7 Prague 16600 6 Czech Republic

Given the growth in structural applications of fibre reinforced concretes (fRCs), the characterization of their mechanical performance, and the formulation of predictive models are necessary. When dealing with fRCs long-term behaviour, concrete creep deformations can be predicted but the fiber-matrix interaction produces new effects, i.e. non-linear bond behaviour, creep of polymeric fibres, affecting the longterm performance of cracked elements. The present paper introduces a novel computational framework simulating the long-term behaviour of cracked fRC elements with polymeric fibres, adopting the Lattice Discrete Particle Model (LDPM) theory. The innovative contributions of the research concern the inclusion of the fibre viscoelastic behaviour. (c) 2021 Elsevier Ltd. All rights reserved.

关键词： MSfRC Viscoelasticity Creep LDPM f M LDPM f

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The legacy of reification: Gillian Rose and the value-form theory challenge to Georg Lukacs

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THESIS ELEVEN 2020年第1期157卷 80-96页

作者： Lazarus, Michael Monash Univ Clayton Vic Australia

This article examines the relationship between Marx's Capital, Georg Lukacs and Critical Theory through the prism of value-form theory. Marx's theorisation of value understands commodities as expressions of the historical form of social relations defined by capital. Products of human labour become values in capitalist production, defined by the abstract quality of undifferentiated quantities of labour-power, exchangeable through the universal character of the market. The social form of this process, Marx identifies as processing a fetish quality, where humans take on the thing-like character of commodities. The impact of this theorisation on Critical Theory has been considerable, beginning with Lukacs' concept of reification. In Part I, I examine the challenge to Lukacs' interpretation of Marx's Capital made by Gillian Rose. She draws attention to a misidentification of reification in Marx, suggesting a strong conceptual distinction between commodity-fetishism and reification. In their conceptual flattening, Rose contends that Lukacs and Critical Theory generalised Marx's value-form theory, losing its speculative character. I argue that despite Rose's suggestion remaining unfulfilled, she helps illuminate important tensions between Marx's value theory and Critical Theory. This comparison allows in Part II for the beginning level of a speculative approach to Marx's Capital to be advanced.

关键词： capital G W f Hegel Georg Lukacs Karl Marx reification Gillian Rose value-form theory

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Effect of Ge addition on the microstructure, mechanical properties, and corrosion behavior of CoCrfeNi high-entropy alloys

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INTERMETALLICS 2021年 132卷

作者： Liu, Hung-Chih Tsai, Che-Wei Natl Tsing Hua Univ Dept Mat Sci & Engn Hsinchu 30013 Taiwan Natl Tsing Hua Univ High Entropy Mat Ctr Hsinchu 30013 Taiwan

Based on the results of many studies devoted to exploring the effect of adding different elements to CoCrfeNi alloys in the field of high-entropy alloys, in this study, Ge is included in CoCrfeNi alloys to form CoCrfeNiGex alloys (molar ratio, x = 0, 0.1, 0.2, and 0.3). Ge is used to improve mechanical properties and corrosion resistance of traditional alloys, but its application in high-entropy alloys has been less discussed. CoCrfeNiGex alloys (x ? 0.3) exhibit a single face-centered cubic phase. Tensile testing of these alloys revealed that the CoCrfeNiGe0.3 alloy exhibited slightly better mechanical properties?a yield strength of 223 MPa, ultimate tensile strength of 617 MPa, and elongation of 63.2%?due to solid-solution hardening. A potentiodynamic polarization test in deaerated 3.5% NaCl solution showed that Ge addition can effectively inhibit pitting corrosion and can improve the corrosion resistance of CoCrfeNi alloys by reducing the corrosion and passive current density.

关键词： A high-entropy alloys B solid-solution hardening Corrosion D microstructure f mechanical testing

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Microstructures and mechanical properties of (CoCrfeMnNi)100-xMox high entropy alloy films

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INTERMETALLICS 2021年 135卷

作者： Huang, Tzu-Hsuan Hsueh, Chun-Hway Natl Taiwan Univ Dept Mat Sci & Engn Taipei 10617 Taiwan

The effects of Mo addition on the microstructures and mechanical properties of CoCrfeMnNi high entropy alloy films (HEAfs) were studied in this work. To achieve this, a series of (CoCrfeMnNi)100-xMox HEAfs was prepared by magnetron co-sputtering. The films were fCC without Mo addition and composed of fCC and HCP structures with minor Mo addition. With the further increase in Mo content, the films transformed to an amorphous structure. Nanoindentation revealed an initial decrease in hardness and then increase with the increasing Mo content. While the initial decrease in hardness could be attributed to the detwinning-induced softening for films with small twin spacing as observed by TEM after micropillar compression, the subsequent increase could be attributed to solid solution strengthening and formation of nanotwins with larger twin spacing and no detwinning observed after compression. Using scratch tests, the Mo-doped HEAfs exhibited a high hardness, good wear resistance and low coefficient of friction. The results of micropillar compression tests showed the increasing compressive yield strength and the decreasing fracture strain with the increasing Mo content. When x = 4.9, the film revealed the optimum mechanical properties with fracture strength of 6.51 GPa and little reduction in ductility.

关键词： A high-entropy alloys Thin films B mechanical properties C deposition D microstructure f nanoindentation

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Integrated multi-band Rf transceiver design for multi-standard applications using 130 nm CMOS technology

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MICROELECTRONICS JOURNAL 2021年 110卷

作者： Mansour, Marwa Zekry, Abdelhalim Ali, Mohammed K. Shawkey, Heba Elect Res Inst ERI Microelect Dept Giza Egypt Ain Shams Univ Fac Engn Elect & Commun Dept Cairo Egypt Fayoum Univ Elect Engn Dept Al Fayyum Egypt Ulm Univ Inst Elect Devices & Circuits Ulm Germany

This paper presents high efficiency, high integration, and wideband low-If radio frequency transceiver for multistandard applications using 130 nm CMOS technology. The proposed low-If transceiver includes receiver, transmitter, and quadrature voltage-controlled power oscillator (QVCO). The proposed receiver consists of a lownoise driver stage designed using Capacitive Cross-Coupling (CCC) common-gate configuration, and I/Q demodulator. While, the proposed transmitter composes of an I/Q modulator and an Rf power amplifier, where the I/Q modulator consists of two up-conversion mixers, a five ports transformer along with switched capacitors bank for reconfigurable Rf output matching. The proposed receiver has a frequency band of 0?10 GHz, while the operating frequency of the proposed transmitter equals 1.5?4 GHz. The proposed Rf transceiver design is suitable for multi-band LTE, IOT, WSN, and multi-standard applications. The proposed receiver achieves a power gain of 15.4 dB, noise figure (Nf) equals 3.8 dB, sensitivity equals 100.2 dBm and a dynamic range of 92.2 dBm. On the other hand, the proposed transmitter has a saturated output power of 23 dBm, power added efficiency (PAE) equals 41%, the power gain of 25 dB, and adjacent channel power ratio (ACPR) of equals 31.8dBc. The proposed receiver and transmitter consume 10.85 mW, and 180.95 mW, respectively, including the QVCO. The receiver and transmitter figures of Merit (foM) equal 191.5 dB and 2.45 dB respectively. The active areas of the proposed receiver and transmitter equal 0 56 mm2 and 1 6 mm2, respectively while the chip areas are 1 6 mm2 and 2 4 mm2, respectively.

关键词： CMOS Class-AB f foM Intermediate frequency (If) Radio frequency (Rf) Receiver Transmitter Transceiver

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fovea-Sparing versus Standard Internal Limiting Membrane Peeling for Myopic Traction Maculopathy: A Study of 102 Consecutive Cases

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OPHTHALMOLOGY RETINA 2020年第12期4卷 1170-1180页

作者： Shiraki, Nobuhiko Wakabayashi, Taku Ikuno, Yasushi Matsumura, Nagakazu Sato, Shigeru Sakaguchi, Hirokazu Nishida, Kohji Osaka Univ Grad Sch Med Dept Ophthalmol 2-2 YamadaokaE-7 Suita Osaka 5650871 Japan Ikuno Eye Ctr Osaka Japan Osaka Univ Inst Open & Transdisciplinary Res Initiat Integrated Frontier Res Med Sci Div Suita Osaka Japan

Purpose: To investigate the long-term outcomes of pars plana vitrectomy (PPV) with fovea-sparing internal limiting membrane (ILM) peeling (fSIP) and standard ILM peeling for myopic traction maculopathy (MTM). Design: Retrospective case series. Participants: A total of 102 eyes of 96 consecutive patients who underwent primary PPV for MTM and were followed up for at least 12 months. Methods: We compared the outcomes of eyes that underwent vitrectomy with fSIP from October 2012 to March 2017 with those of eyes that underwent vitrectomy with standard ILM peeling from June 2008 to September 2012. Main outcome measures: Best-corrected visual acuity (BCVA) at 12 months and the final follow-up visit after surgery, time to MTM resolution, and postoperative complications such as macular hole (MH) formation. Results: There were 26 and 76 eyes in the fSIP and standard ILM peeling groups, respectively. In both groups, the mean visual acuity (VA) at the 12-month follow-up was significantly improved relative to the mean preoperative VA (P < 0.001 for both groups). The preoperative and postoperative BCVA (logarithm of the minimum angle of resolution) showed no significant between-group differences (preoperative: 0.60 +/- 0.35 in the fSIP group and 0.61 +/- 0.39 in the standard ILM peeling group, P = 0.935;postoperative BCVA: 0.32 +/- 0.43 in the fSIP group and 0.37 +/- 0.38 in the standard ILM peeling group, P = 0.281). The mean time to the resolution of foveal retinal detachment and schisis was also comparable between groups (8.9 +/- 4.8 months in the fSIP group and 6.9 +/- 4.6 months in the standard ILM peeling group, P = 0.084). None of the eyes in the fSIP group and 6 eyes (8%) in the standard ILM peeling group developed postoperative MH. Consequently, the BCVA at 12 months deteriorated by 3 or more lines for 4 eyes (5%) in the standard ILM peeling group;this deterioration was not observed for any eye in the fSIP group. Risk factors for postoperative MH formation were worse pre

关键词： BBG Brilliant Blue-G C 3 f 8 perfluoropropane EZ ellipsoid zone fSIP fovea-sparing internal limiting membrane peeling ILM internal limiting membrane logMAR logarithm of the minimal angle of resolution MH macular hole MTM myopic traction maculopathy PPV pars plana vitrectomy SD-OCT spectral-domain OCT VA visual acuity

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Evaluating strategies for implementing industry 4.0: a hybrid expert oriented approach of BWM and interval valued intuitionistic fuzzy TODIM

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ECONOMIC RESEARCH-EKONOMSKA ISTRAZIVANJA 2020年第1期33卷 1600-1620页

作者： Mahdiraji, Hannan Amoozad Zavadskas, Edmundas Kazimieras Skare, Marinko Kafshgar, fatemeh Zahra Rajabi Arab, Alireza Univ Tehran Dept Ind Management Tehran Iran Coventry Univ Fac Business & Law Sch Strategy & Leadership Coventry W Midlands England Gediminas Tech Univ Inst Sustainable Construct Vilnius Lithuania Juraj Dobrila Univ Pula Econ & Tourism Preradoviceva Croatia Univ Mazandaran Fac Econ & Adm Sci Babol Sar Iran Univ Tehran Fac Management Tehran Iran

Developing and accepting industry 4.0 influences the industry structure and customer willingness. To a successful transition to industry 4.0, implementation strategies should be selected with a systematic and comprehensive view to responding to the changes flexibly. This research aims to identify and prioritise the strategies for implementing industry 4.0. for this purpose, at first, evaluation attributes of strategies and also strategies to put industry 4.0 in practice are recognised. Then, the attributes are weighted to the experts' opinion by using the Best Worst Method (B.W.M.). Subsequently, the strategies for implementing industry 4.0 in fara-Sanat Company, as a case study, have been ranked based on the Interval Valued Intuitionistic fuzzy (I.V.I.f) of the T.O.D.I.M. method. The results indicated that the attributes of 'Technology', 'Quality', and 'Operation' have respectively the highest importance. furthermore, the strategies for "new business models development', 'Improving information systems' and 'Human resource management' received a higher rank. Eventually, some research and executive recommendations are provided. Having strategies for implementing industry 4.0 is a very important solution. Accordingly, multi-criteria decision-making (M.C.D.M.) methods are a useful tool for adopting and selecting appropriate strategies. In this research, a novel and hybrid combination of B.W.M.-T.O.D.I.M. is presented under I.V.I.f. information.

关键词： industry 4 0 Best Worst Method (B W M ) Internal Valued Intuitionistic fuzzy (I V I f ) multi-criteria decision-making (M C D M ) T O D I M information systems

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