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Retractable compact Directed complete Poset （Acts）

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Algebra colloquium 2017年第4期24卷 625-638页

作者： m. mehdl Ebrahiml mojgan mahmoudi mahdieh Yavari Department of mathematics Shahid Bebeshti University G.C. Tehran 19839 lran

Taking domains in the one hand and actions of a semigroup （automaton） on the other, as two crucial notions in mathematics as well as in computer science, we consider the notion of compact directed complete poset （acts）, and investigate the interesting notion of absolute retractness for such ordered structures. As monomorphisms and embeddings for domain acts are different notions, we study absolute retractness with respect to both the class of monomorphisms and that of embed- dings for compact directed complete poset （acts）. We characterize the absolutely retract compact dcpos as complete compact chains. Also, we give some examples of compact di- rected complete poset acts which are （g-）absolutely retract （with respect to embeddings） and show that completeness is not a sufficient condition for （g-）absolute retractness.

关键词： action of a monoid directed complete poset compact absolutely retract

Effect of retained austenite and nonmetallic inclusions on the thermal/electrical properties and resistance spot welding nuggets of Si-containing TRIP steels

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International Journal of minerals,metallurgy and materials 2019年第1期26卷 52-63页

作者： V.H.Vargas I.mejía V.H.Baltazar-Hernández c.maldonado metallurgy and materials Research Institute Universidad Michoacana de San Nicolás de Hidalgo Edificio "U" Ciudad Universitaria materials Science and Engineering Program Autonomous University of Zacatecas

Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JmatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, c, Al, and mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets.

关键词： transformation-induced plasticity steel retained austenite non-metallic inclusions magnetic saturation electrical properties thermal properties resistance spot welding nugget

mEROmORPHIc p-VALENT FUNcTION WITH FIXED SEcOND NEGATIVE cOEFFIcIENTS

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Analysis in Theory and Applications 2005年第2期21卷 132-142页

作者： m.Darus Universiti Kebangsaan malaysia malaysia

In this paper we consider the class ∑^＊（p,α,β,k,c） consisting of analytic functions with negativecoefficients and fixed second coefficient. The object of the present paper is to give coefficient estimates, convex linear combinations, some distortion theorems and radii of starlikeness and convexity for f（z） in the class ∑^＊（p,α,β,k,c） .

关键词： analytic function meromorphic function negative coefficient fixed second negative coefficient growth and distortion theorem

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奥贝球铁的动力断裂韧性

铸造 1990年第11期39卷 43-44页

作者：张晓明 B.Faucher K.c.Wang m.Gagne 加拿大

研究了含锰量,含硅量和等温淬火时间对奥贝球铁动力断裂韧性的影响。共熔炼了9炉铁水,其cE控制在4．3~4．7%,除锰外,每次加入1%铜和0．3%钼,以使铸件获得足够硬度,并防止试块在热处理过程中的珠光体转变。

关键词：奥氏体贝氏体球墨铸铁韧性断裂

Experimental platform for the investigation of magnetized-reverse-shock dynamics in the context of POLAR

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High Power Laser Science and Engineering 2018年第3期6卷 36-49页

作者： B. Albertazzi E. Falize A. Pelka E Brack E Kroll R. Yurchak E. Brambrink E mabey N. Ozaki S. Pikuz L. Van Box Som J. m. Bonnet-Bidaud J. E. cross E. Filippov G. Gregori R. Kodama m. mouchet T. morita Y. Sakawa R. E Drake c. c. Kuranz m. J.-E. manuel c. Li E Tzeferacos D. Lamb U. Schramm m. Koenig LULI- cNRS Ecole Polytechnique CEA: Universite Paris-Saclay UPmc Univ Paris 06: Sorbonne Universites- F-91128 Palaiseau cedex France cEA-DAm-DIF F-91297 Arpajon France cEA Saclay DSM/Irfu/Service d'Astrophysique F-91191 Gif-sur- Yvette France Helmholtz-Zentrum Dresden - Rossendorf HZDR Bautzner Landstrαβe 400 01328 Dresden Germany Department of Atmospheric Oceanic and Space Sciences University of Michigan Ann Arbor M148109 USA Graduate School of Engineering Osaka University Suita Osaka 565-0871 Japan JIHT-RAS 13-2 lzhorskaya st. Moscow 125412 Russia National Research Nuclear University mEPhl Moscow 115409 Russia Department of Physics University of Oxford Parks Road Oxford OX1 3PU UK Institute of Laser Engineering Osaka University Suita Osaka 565-0871 Japan LUTH Observatoire de Paris UMR CNRS 8102 Universite Paris Diderot 92190 Meudon France Department of Energy Engineering Science Faculty of Engineering Sciences Kyushu University Japan General Atomics San Diego CA 92121 USA Plasma Science and Fusion center Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge MA 02139 USA Flash center for computational Science University of Chicago IL 60637 USA

The influence of a strong external magnetic field on the collimation of a high mach number plasma flow and its collision with a solid obstacle is investigated experimentally and numerically. The laser irradiation （I - 2 × 10^14 W. cm-2） of a multilayer target generates a shock wave that produces a rear side plasma expanding flow. Immersed in a homogeneous 10 T external magnetic field, this plasma flow propagates in vacuum and impacts an obstacle located a few mm from the main target. A reverse shock is then formed with typical velocities of the order of 15-20 4- 5 km/s. The experimental results are compared with 2D radiative magnetohydrodynamic simulations using the FLASH code. This platform allows investigating the dynamics of reverse shock, mimicking the processes occurring in a cataclysmic variable of polar type.

关键词： accretion processes high-power laser hydrodynamics laboratory astrophysics polar radiative shocks

mid-infrared upconversion imaging using femtosecond pulses

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Photonics Research 2019年第7期7卷 98-106页

作者： Ashik A.S. callum F.O'Donnell S.chaitanya Kumar m.Ebrahim-Zadeh P.Tidemand-Lichtenberg c.Pedersen DTU Fotonik Technical University of DenmarkDK-4000 RoskildeDenmark Radiantis Edifici RDITMediterranean Technology Park08860 CastelldefelsBarcelonaSpain IcFO-lnstitut de ciencies Fotoniques Barcelona Institute of Science and Technology08860 CastelldefelsBarcelonaSpain Institucio catalana de Recerca i Estudis Avan gats(IcREA) Passeig Lluis Companys 2308010 BarcelonaSpain

mid-infrared(mid-IR) imaging and spectroscopic techniques have been rapidly evolving in recent years, primarily due to a multitude of applications within diverse fields such as biomedical imaging, chemical sensing, and food quality inspection. mid-IR upconversion detection is a promising tool for exploiting some of these applications. In this paper, various characteristics of mid-IR upconversion imaging in the femtosecond regime are investigated using a 4 f imaging setup. A fraction of the 100 fs, 80 mHz output from a Ti:sapphire laser is used to synchronously pump an optical parametric oscillator, generating 200 fs mid-IR pulses tunable across the 2.7–4.0 μm wavelength range. The signal-carrying mid-IR pulses are detected by upconversion with the remaining fraction of the original pump beam inside a bulk LiNbO3 crystal, generating an upconverted field in the visible/near-IR range, enabling silicon-based ccD detection. Using the same pump source for generation and detection ensures temporal overlap of pulses inside the nonlinear crystal used for upconversion, thus resulting in high conversion efficiency even in a single-pass configuration. A theory is developed to calculate relevant acceptance parameters, considering the large spectral bandwidths and the reduced interaction length due to group velocity mismatch, both associated with ultrashort pulses. Furthermore, the resolution of this ultrashort-pulsed upconversion imaging system is *** is demonstrated that the increase in acceptance bandwidth leads to increased blurring in the upconverted *** presented theory is consistent with experimental observations.

关键词： upconversion observations femtosecond regime

carrier Density and Electric Field Dependent Nonlinear Transport of chemical Vapor Deposition Graphene

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chinese Physics Letters 2013年第3期30卷 127-130页

作者： KHALIL Hafiz m.W. KELEKcI Ozgur NOH Hwayong Department of Physics and Graphene Research Institute Sejong UniversitySeoul 143-747Korea

We report on the measurements of nonlinear current-voltage characteristics of graphene fabricated by chemical vapor *** current-voltage characteristic is described by a power law with a superlinear dependence of the current on the voltage,and the nonlinearity depends on the carrier density and the excitation *** nonlinearity is strongest at the Dirac point and becomes weaker as the carrier density *** the Dirac point,we also observe a crossover to a much stronger nonlinear transport when the electric field increases above 104 V/m.

关键词： deposition. nonlinearity nonlinear

Thyme oil inclusion levels in a rabbit ration: Evaluation of productive performance, carcass criteria and meat quality under hot environmental conditions

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Animal Nutrition 2018年第4期4卷 410-416页

作者： Ahmed A.A.Abdel-Wareth Eman m.m.Taha Karl-Heinz Südekum Jayant Lohakare Department of Animal and Poultry Production Faculty of Agriculture South Valley University Department of Food Science and Technology Faculty of Agriculture South Valley University Institute of Animal Science University of Bonn Department of Agriculture-Animal Science University of Arkansas at Pine Bluff

The aim of this study was to determine the impact of thyme essential oil supplementation in rabbit rations on performance, carcass criteria, and meat quality under hot environmental conditions. A total of 75, 4-week-old californian male rabbits were assigned to 5 dietary treatments until 12 weeks of *** rabbits were reared in an open house system(38c average ambient temperature and 26% to 35%relative humidity). Treatments were as follows: unsupplemented standard ration, negative control(cON); standard ration supplemented with 1.50 g/kg olive oil as carrier, positive control(POS);POS t 50 mg/kg thyme oil(TO1); POS t 100 mg/kg thyme oil(TO2); and POS t 150 mg/kg thyme oil(TO3). Dietary thyme oil up to 150 mg/kg improved(P mance in comparison to cON. The highest average daily gain and most efficient feed conversion ratio(linear,P c, P corporation of thyme oil improved(P carcass criteria and decreased(P capular fat without any side effects on internal organs. Notably, the water holding capacity of rabbit meat was greater(P compared with cON. Differences were also recorded in oxymyoglobin and metmyoglobin contents in rabbit meat among treatments. In conclusion, thyme oil of a specified composition and to be added to a rabbit ration up to 100 mg/kg using 1.50 g/kg olive oil as a carrier can be used as an efficient feed additive for improving productive performance of rabbits under hot environmental conditions.

关键词： Antioxidant Essential oil meat characteristics Nutrition Production

Supercritical carbon Dioxide Extraction of Andrographolide from Andrographis paniculata： Effect of the Solvent Flow Rate, Pressure, and Temperature

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chinese Journal of chemical Engineering 2007年第6期15卷 877-883页

作者： A.c. Kumoro masitah Hasan Department of chemical Engineering Faculty of Engineering Diponegoro University SH Road Tembalang Se-.marang 50139 Indonesia Department of chemical Engineering Faculty of Engineering University of Malaya Kuala Lumpur 50603 Malaysia

Andrographis paniculata Nees has been extensively used for traditional medicine and help against fever dysentery, diarrhoea, inflammation, and sore throat. In this study, andrographolide, the main component of this plant was extracted from the leaves of A. paniculata using supercritical carbon dioxide. The operating pressures were varied from 7.50 to 20mPa, the temperatures were varied from 30℃ to 60℃, and the flow rates were varied from 0.5 to ***^-1. The best extraction condition occurred at 10mPa, 40℃, and a flow rate of ***^-1 for a 3g sample of A. paniculata ground-dried leaves. The measured extraction rate was found to be about 0.0174g of andrographolide per gram of andrographolide present in the leaves per hour of operation. The future studies must focus on the interaction between the various operating parameters such as temperature, pressure, and flow rate of supercritical carbon dioxide.

关键词： supercritical carbon dioxide extraction andrographolide Andrographis paniculata