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Effect of Cardioxane and selenium on Lipoperoxidation and Levels of Dopamine in Rat Brain and Heart

neuroscience & Medicine 2019年第4期10卷 354-368页

作者： David Calderón Guzmán norma Osnaya Brizuela Gerardo Barragán Mejía Hugo Juárez Olguín Lulú sánchez Reyes Armando Valenzuela Pereza norma Labra Ruiz Daniel santamaría del Angel Laboratory of neurosciences Instituto Nacional de Pediatría (INP) Mexico City Mexico Laboratory of Experimental Bacteriology INP Mexico City Mexico Laboratory of Pharmacology INP Mexico City Mexico Faculty of Medicine Universidad Nacional Autónoma de Mexico Mexico City Mexico.

Background: Cardioxane has been probed in patien.s.with advanced malignancies to protect the heart. selenium, an essential micronutrient exerts varieties of functions such as antioxidant. The aim of this study was to test if cardioxane (CDX) and selenium (se) have additive antioxidant protective effect on brain and heart, and their relation with dopamine levels. Methods: Thirty-six male Wistar rats divided in groups of 6 animals each, were treated as follows: G1, saline solution 0.9% (control);G2, 100 mg/kg of CDX;G3, 60 μg/kg of se;G4, 20 mg/kg of 3-nitropropionic acid (3nP);G5, 3nP + CDX and G6, 3nP + se. 3nP was used as an oxidative stress inducer. Drugs were admin.s.ered intraperitoneally for 5 days. The animals were sacrificed on the last day of treatment and the brain and heart were extracted and used to measure lipid peroxidation, dopamine, glutathione (GsH), ATPase, calcium, and H2O2. Results: In G2 and G5, dopamine decreased in cortex and striatum while GsH increased in heart, cortex and cerebellum/medulla oblongata. ATPase activity increased in heart and cortex of groups 2, 3, 5 and 6. Lipoperoxidation and H2O2 increased in cortex of animals treated with 3nP. Conclusion: These results suggest that CDX increases antioxidant capacity in the brain and heart while selenium promotes alteration in dopamine metabolism in view of the capacity of 3nP to generate free radicals.

关键词： Brain Dopamine Heart Cardioxane selenium 3-nitropropionic Acid

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Transparent flexible ZnO/MWCn.s.PBMA ternary nanocomposite film with enhanced mechanical properties

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science China Chemistry 2016年第8期59卷 1010-1017页

作者： Xingwei Han Xiaofei Zeng Jiexin Wang dejia Kong n.R. Foster Jianfeng Chen state Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China department of Chemical Engineering Columbia University New York 10027 USA supercritical Fluids Research Group School of Chemical Engineering University of New South Wales Sydney New South Wales 2052 Australia Research Center of the Min.s.ry of Education for High Gravity Engineering and Technology Beijing University of Chemical Technology Beijing 100029 China

Functional organic-inorganic nanocomposites with high transparency show significant potential application in many fields. However, it is still a great challenge to prepare flexible transparent nanocomposites due to the intrinsic stiffn.s. of the nanoparticles and the poor interaction between nanopartieles and organic matrices. In this work, a transparent ternary nanocomposite film with enhanced mechanical performance is fabricated by two-steps. First, the transparent ternary ZnO/MWCn.s.n-butyl methacrylate （BMA） nanodispersion is prepared by mixing the ZnO/BMA and MWCn.s.BMA dispersions directly. Then, the ternary nanocoposites film is fabricated via in.s.tu bulk polymerization of the above nanodispersions. As a result, the tensile strength of the ZnO/MWCn.s.poly-n-butyl methacrylate （PBMA） ternary film is enhanced by 42% and the elongation at break is three times that of ZnO/PBMA nanocomposite. The hardn.s. of the film increases from 5B to 1H with 40 wt% ZnO. These results indicate that ZnO and MWCn.s.can improve the mechanical properties of the composite significantly. Importantly, the ternary nanocomposite film still remains high transparency and exhibit excellent UV-shielding performance. The as-prepared transparent multifunctional nanocomposite films have promising applications in optical materials and devices, such as optical filters, contact lenses and protection packing.

关键词： ZnO carbon nanotubes transparent ternary nanocomposite UV-shielding mechanical properties

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Thermophoresis and Brownian motion effects on boundary layer flow of nanofluid in presence of thermal stratification due to solar energy

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Applied Mathematics and Mechanics(English Edition) 2012年第6期33卷 765-780页

作者： n.AnBUCHEZHIAn K.sRInIVAsAn K.CHAnDRAsEKaran R.KAnDAsAMY department of Mechanical Engineering Sri Guru Institute of Technology department of Mechanical Engineering Anna University department of Mechanical Engineering R.M.K.Engineering College Research Centre for Computational Mathematics Faculty of ScienceTechnology and Human DevelopmentUniversiti Tun Hussein Onn Malaysia

The problem of laminar fluid flow, which results from the stretching of a vertical surface with variable stream conditions in a nanofluid due to solar energy, is in- vestigated numerically. The model used for the nanofluid incorporates the effects of the Brownian motion and thermophoresis in the presence of thermal stratification. The sym- metry groups admitted by the corresponding boundary value problem are obtained by using a special form of Lie group transformations, namely, the scaling group of transfor- mations. An exact solution is obtained for the translation.s.mmetrys, and the numerical solutions are obtained for the scaling symmetry. This solution depen.s.on the Lewis number, the Brownian motion parameter, the thermal stratification parameter, and the thermophoretic parameter. The conclusion is drawn that the flow field, the temperature, and the nanoparticle volume fraction profiles are significantly influenced by these param- eters. nanofluids have been.s.own to increase the thermal conductivity and convective heat transfer performance of base liquids. nanoparticles in the base fluids also offer the potential in improving the radiative properties of the liquids, leading to an increase in the efficiency of direct absorption.s.lar collectors.

关键词： solar radiation Brownian motion nanofluid thermophoresis thermalstratification

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Methane hydrate stability in the presence of water-soluble hydroxyalkyl cellulose

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journal of natural Gas Chemistry 2012年第2期21卷 119-125页

作者： M. Mohammad-Taheri A. Zarringhalam Moghaddam K. nazari n. Gholipour Zanjani Chemical Engineering department Tarbiat Modares University Chemistry and Petrochemical Division Research Institute of Petroleum Industry

The effect of low-dosage water-soluble hydroxyethyl cellulose （approximate MW～90,000 and 250,000） as a member of hydroxyalkyl cellulosic polymer group on methane hydrate stability was investigated by monitoring hydrate dissociation at pressures greater than atmospheric pressure in a closed vessel. In particular, the influence of molecular weight and mass concentration of hydroxyethyl cellulose （HEC） was studied with respect to hydrate formation and dissociation. Methane hydrate formation was performed at 2℃ and at a pressure greater than 100 bar. Afterwards, hydrate dissociation was initiated by step heating from -10℃ at a mild pressure of 13 bar to 3℃, 0℃ and 2℃. With respect to the results obtained for methane hydrate formation/dissociation and the amount of gas uptake, we concluded that HEC 90,000 at 5000 ppm is suitable for long-term gas storage and transportation under a mild pressure of 13 bar and at temperatures below the freezing point.

关键词： hydrate stability dissociation kinetic low-dose polymer gas storage

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Workflow to numerically reproduce laboratory ultrasonic datasets

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journal of Rock Mechanics and Geotechnical Engineering 2014年第6期6卷 582-590页

作者： A.Biryukov n.Tisato G.Grasselli department of Civil Engineering University of TorontoToronto Ontario Canada

The risks and uncertainties related to the storage of high-level radioactive waste （HLRW） can be reducedthan.s.to focused studies and investigations. HLRWs are going to be placed in deep geological repositories,enveloped in an engineered bentonite barrier, whose physical conditions are subjected tochange throughout the lifespan of the infrastructure. seismic tomography can be employed to monitor itsphysical state and integrity. The design of the seismic monitoring system can be optimized via conductingand analyzing numerical simulations of wave propagation in representative repository ***, the quality of the numerical results relies on their initial calibration. The main aim of this paperis to provide a workflow to calibrate numerical tools employing laboratory ultrasonic datasets. The finitedifference code sOFI2D was employed to model ultrasonic waves propagating through a laboratorysample. specifically, the input velocity model was calibrated to achieve a best match between experimentaland numerical ultrasonic traces. Likely due to the imperfections of the contact surfaces, theresultant velocities of P- and s-wave propagation tend to be noticeably lower than those a prioriassigned. Then, the calibrated model was employed to estimate the attenuation in a montmorillonitesample. The obtained low quality factors （Q） suggest that pronounced inelastic behavior of the clay has tobe taken into account in geophysical modeling and analysis. Consequently, this contribution.s.ould beconsidered as a first step towards the creation of a numerical tool to evaluate wave propagation innuclear waste repositories. 2014 Institute of Rock and soil Mechanics, Chin.s. Academy of sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： numerical methods Calibration Velocity model Bentonite Viscoelastic wave propagation

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Improvement of Microstructure and Mechanical Behavior of Gas Tun.s.en Arc Weldmen.s.of Alloy C-276 by Current Pulsing

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Acta Metallurgica sinica(English Letters) 2015年第2期28卷 208-215页

作者： M.Manikandan n.Arivazhagan M.nageswara Rao G.Madhusudhan Reddy school of Mechanical and Building sciences VIT University defence Metallurgical and Research Laboratory

superalloy C-276 is known to be prone to hot cracking during fusion welding by Gas Tun.s.en Arc method. Microsegregation occurring during cooling of fusion zone with consequent appearance of topologically close-packed phases P and IX has been held responsible for the observed hot cracking. The present work investigated the possibility of suppressing the microsegregation in weldmen.s.by resorting to current pulse. Weldmen.s.were made by continuous current gas tun.s.en arc welding and pulsed current gas tun.s.en arc welding using ERniCrMo-4 filler wire. The weld join.s.were studied with respect to microstructure, microsegregation, and mechanical properties. Optical microscopy and scanning electron microscopy were employed to study the microstructure. Energy-Dispersive X-ray spectroscopy was carried out to evaluate the extent of microsegregation. Tensile testing was carried out to determine the strength and ductility. The results show that the join.s.fabricated with pulsed current gave rise to narrower welds with practically no heat affected zone, a refined microstructure in the fusion zone, reduced microsegregation, and superior combination of mechanical properties.

关键词： Alloy C-276 Pulsed current gas tun.s.en arc welding Microsegregation

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syntheses of DL-threo-Thiamphenicol via Green Oxidation

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Chemical Research in Chin.s. Universities 2006年第5期22卷 602-605页

作者： LIU Kai Robert Franzén YU Xiao-jing ZHAnG Jun XU You-jun school of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 P. R. China Institute of Materials Chemistry Tampere University of Technology Korkeakoulunkatu 8 FIN-33720 Tampere Finland

Four methyl aryl thioethers related to thiamphenicol syntheses and methyl phenyl sulfide were cleanly oxidized into methyl sulfon.s.in high to excellent yields via catalytic green oxidation with aqueous hydrogen peroxide in combination with sodium tun.s.ate. When the same reactions were similarly performed in the absence of the catalyst, the corresponding sulfoxides could be obtained. This viable synthetic approach for the synthesis of DL-threo-thiamphenicol is a simple procedure, which has an economic advantage in view of its application for the large-scale synthesis because it can be carried out under mild conditions.

关键词： Green oxidation Hydrogen peroxide sodium tun.s.ate Thiamphenicol

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VARIOUs nOTIOns OF ORTHOGOnALITY In nORMED sPACEs

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Acta Mathematica scientia 2013年第5期33卷 1387-1397页

作者： n.B.OKELO J.O.AGURE P.O.OLECHE school of Mathematics and Actuarial science Jaramogi Oginga Odinga University of Science and Technology school of Mathematics Statistics and Actuarial Science Maseno University

In this paper, we present various notions and aspects of orthogonality in normed spaces. Characterizations and generalizations of orthogonality are also consid- ered. Results on orthogonality of the range and the kern... 详细信息

关键词： orthogonality normed space elementary operator

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Giant non-linear susceptibility of hydrogenic donors in.s.licon and germanium

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Light(science & Applications) 2019年第1期8卷 624-630页

作者： nguyen H.Le Grigory V.Lanskii Gabriel Aeppli Benedict n.Murdin Advanced Technology Institute and sEPnet University of SurreyGuildford GU27XHUK Institute of Monitoring of Climatic and Ecological systems sB RAs 10/3 Academical Ave.Tomsk 634055Russia Laboratory for solid state Physics ETH ZurichZurich CH-8093Switzerland Institut de Physique EPF LausanneLausanne CH-1015Switzerland Paul scherrer Institut VilligenPSI CH-5232Switzerland

Implicit summation is a technique for the conversion of sums over intermediate states in multiphoton absorption and the high-order susceptibility in hydrogen into simple ***,we derive the equivalent technique for hydrogenic impurities in multi-valley *** the absorption has useful applications,it is primarily a loss process;conversely,the non-linear susceptibility is a crucial parameter for active photonic *** si:P,we predict the hyperpolarizability ranges from χ^((3))/n_(3D)=2.9 to 580×10^(−38 )m^(5)/V^(2) depending on the frequency,even while avoiding *** samples of a reasonable density,n3D,and thickn.s.,L,to produce thirdharmonic generation at 9 THz,a frequency that is difficult to produce with existing solid-state sources,we predict that χ^((3)) should exceed that of bulk Insb and χ^((3))L should exceed that of graphene and resonantly enhanced quantum wells.

关键词： susceptibility hydrogenic absorption

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Radiation effect on the optical and electrical properties of Cdse(In)/p-si heteroj unction photovoltaic solar cells

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journal of semiconductors 2012年第10期33卷 1-4页

作者： M.Ashry s.Fares national Center for Radiation Research and Technology(nCRRT) AEAP.O.29 Nasr CityEgypt

The efficiency and radiation resistance of solar cells are *** are then fabricated in the form of n-Cdese（In）/p-si heterojunction cells by electron beam evaporation of a stoichiomteric mixture of Cdse and In to make a thin film on a p-si single crystal wafer with a thickn.s. of 100μm and a resistivity of～1.5Ω·cm at a temperature of 473 *** short-circuit current density（jsc）,open-circuit voltage（Voc）,fill factor（ff） and conversion efficiency（η） under 100 mW/cm^2（AMI） intensity,are 20 mA/cm^2,0.49 V,0.71 and 6%respectively. The cells were exposed to different electron doses（electron beam accelerator of energy 1.5 MeV,and beam intensity 25 mA）.The cell performance parameters are measured and discussed before and after gamma and electron beam irradiation.

关键词： n-Cdse(In)/p-si solar cells performance electron beam radiation effects

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