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Adsorption properties of rosm.rinus officinalis oil as green corrosion inhibitors on c38 steel in 0.5 m H_2SO_4

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Acta metallurgica Sinica(English Letters) 2010年第1期23卷 13-20页

作者： E.El Ouariachi j.Paolini m.Bouklah A.Elidrissi A.Bouyanzer B.Hammouti j-m.Desjobert j.costa Laboratoire de chimie Appliqu'ee et Environnement Facult'e des SciencesUniversit'e Mohamed PremierBP71760000 OujdaMorocco Umr cNrS 6134 Laboratoire de Chimie des Produits NaturelsUniversit'e de CorseFrance

rosm.rinus officinalis essential oil obtained by hydrodistillation was tested as corrosion inhibitor of steel in 0.5 m H2SO4 using weight loss measurements, and electrochemical .polarisation methods. results obtained indicate that the corrosion rate is reduced and r. officinalis oil adsorbs on the metal surface and then inhibits corrosion process. Its inhibition efficiency increases with oil increasing content to reach 61% at 1 g/L. Polarisation curves indicate that rO acts as a cathodic inhibitor. The inhibition efficiency of naturally oil remains slightly constant with the rise of temperature. chemical analysis of r. officinalis essential oil was carried out using capillary Gc and Gc/mS. The oil composition was characterized by high amount of oxygenated monoterpene （77%） with 1,8-cineol （52.1%） as main component. Discussion of adsorption was investigated on the the isotherm adsorption of essential oil on basis of essential oil composition. Finally the steel has been also reported.

关键词： rosm.rinus officinalis oil Adsorption corrosion Inhibition Steel 1,8-cineol

Polym.r Sensitized Quasi Solid-State Photovoltaic cells Using Derivatives of Polythiophene

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journal of materials Science & Technology 2006年第6期22卷 811-816页

作者： G.K.r.Senadeera j.m.r.c.Fernando Institute of Fundamental Studies Hantane RoadKandySri Lanka Institute of Fundamental Studies Hantane RoadKandySri Lanka Postgraduate Institute of ScienceUniversity of PeradeniyaPeradeniyaSri Lanka

Substituted thiophene sensitized, nanocrystalline TiO2-based quasi solid-state solar cells were fabricated by using either poly （3-thiophene acetic acid）（P3TAA） or a copolym.r with poly （3-thiophene acetic acid）-poly （hexyl thiophene）（P3TAA-PHT） polym.rs and copper iodide （cul） as a hole conducting material together with an ionic liquid 1-ethyl-3-methylimidazolium bis （trifluoromethylsulfonyl） amide and lithium bis （triflu- oromethanesulfone） imide as additives for charge transport promotion. Dramatic enhancements in the cell performances were observed with the additives in cul. While the cell sensitized with P3TAA generated a short-circuit photocurrent of -1.45 ***^-2, an open-circuit photovoltage of -345 mV with a total power conversion efficiency of -0.3% under simulated full sunlight of 100 mW-cm^-2 （air mass： 1.5）, the cell sensitized with copolym.r P3TAA-PHT delivered -0.25% efficiency under the same conditions with -1.23 mA-cm^-2 as photocurrent and -371 mV as photovoltage.

关键词： Solar cells Polym.rs Titanium dioxide

mIcrOBrIDGE TESTING OF YOUNG'S mODULUS AND rESIDUAL STrESS OF NIcKEL FILm ELEcTrOPLATED ON SILIcON WAFEr

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Acta metallurgica Sinica(English Letters) 2004年第3期17卷 247-254页

作者： Y.Zhou c.S.Yang j.A. chen G.F. Ding L. Wang m.j Wang Y.m Zhang T.H Zhang Key Laboratory for Thin Film and microfabrication of ministry of Education Research Institute of Micro/Nanometer Science and Technology Shanghai Jiaotong University Shanghai 200030 China State Key Laboratory of Nonlinear mechanics (LNm) Institute of Mechanics The Chinese Academy of Sciences Beijing 100080 China.

microbridge testing is used to measure the Young's modulus and residual stresses of metallic *** film microbridges with widths of several hundred microns are fabricated by microelectromechanical *** order to measure the mechanical properties of nickel film microbridges,special shaft structure is designed to solve the problem of getting the load--deflection curves of metal film microbridge by Nanoin--denter XP system with normal Berkovich *** analysis of the micro--bridge load--deflection curve is proposed to evaluate the Young's modulus and residual stress of the films *** calculated results based on the experimental measurements show that the average Young's modulus and residual stress are around 190GPa and 175mPa respectively,while the Young's modulus measured by Nano-hardness method on nickel film with silicon substrate is 186.8±7.34GPa.

关键词： nickel film microbridge mEmS mechanical property loadeflection measurement

Study on thermal stability of poled non-linear optical polym.rs

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chinese journal of chemistry 1996年第5期14卷 472-480页

作者： mhlmann G.r. vanderVorst c.P.j.m. AKZO NOBEL research Laboratories Arnhem P.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe Netherlands

A logarithmic expression is proposed to describe relaxation of the polar order in side chain polym.rs, together with a new way of plotting temperature dependent relaxation data. This results in a straight line extending even below the glass transition temperature in the case of poled nonlinear optics (NLO) side chain polym.rs. A simple procedure to determine the rotational diffusion constant D-r is given and D-r values of several polym.r systems have been evaluated and compared with each other. It appears that, starting from the conventional and well known poled polym.r system currently applied, a further lowering of D-r by about 3 orders of magnitude is necessary in order to reach an acceptable orientational stability or lifetime of poled polym.rs for practical applications. Attempts have been made to introduce electron push-pull substituents into high thermostable molecular frameworks and results of preliminary measurements are reported.

关键词： thermal stability poled polym.r film organic nonlinear optical materials

ON STABILITY OF m-VArIATE c^1 INTErPOLATION

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Analysis in Theory and Applications 1993年第1期9卷 18-32页

作者： j.Peters m.Sitharam Department of mathematics rensselaer Polytechnic Institute Troy NY 12180-3590 U.S.A. mathematical Sciences Kent State University Kent OH 44242 U.S.A.

*** mesh(triangulation)is constructed that generalizes the two-dimensional 4-direction mesh to r^*** mesh,with symmetric,shift-invariant values at the vertices,is shown to admit a bounded c^1 interpolant if and only if the alternating sum of the values at the vertices of any 1-cube is *** im- plies thai interpolation at the vertices of an m-dimensional,simplicial mesh by a c^1 piecewise polynomial of degree m+1 with one piece per simplex is unstable.

关键词： ON STABILITY OF m-VArIATE c~1 INTErPOLATION

Direct Num.rical Simulation of convective Heat Transfer in a Zero-Pressure-Gradient Boundary Layer with Supercritical Water

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journal of Thermal Science 2012年第1期21卷 49-59页

作者： c. Azih j.r. Brinkerhoff m.I. Yaras Department of mechanical and Aerospace Engineering Carleton University

Experimental research has long shown that forced-convective heat transfer in wall-bounded turbulent flows of fluids in the supercritical thermodynamic state is not accurately predicted by correlations that have been developed for single-phase fluids in the subcritical thermodynamic state. In the present computational study, the statistical properties of turbulent flow as well as the development of coherent flow structures in a zero-pressuregradient flat-plate boundary layer are investigated in the absence of body forces, where the working fluid is in the supercritical thermodynamic state. The simulated boundary layers are developed to a friction reynolds number of 250 for two heat-flux to mass-flux ratios corresponding to cases where normal heat transfer and im.roved heat transfer are observed. In the case where im.roved heat transfer is observed, spanwise spacing of the near-wall coherent flow structures is reduced due to a relatively less stable flow environment resulting from the lower magnitudes of the wall-normal viscosity-gradient profile.

关键词： boundary layer turbulence supercritical fluids im.roved heat transfer DNS

Significance of Stefan blowing effect on flow and heat transfer of casson nanofluid over a moving thin needle

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communications in Theoretical Physics 2021年第9期73卷 51-58页

作者： A m.jyothi r Naveen Kum.r r j Punith Gowda B c Prasannakum.ra Bangalore Institute of Technology BangaloreIndia Department of Studies and research in mathematics Davangere UniversityDavangere-577002KarnatakaIndia

The current mathematical model explains the influence of non-linear thermal radiation on the casson liquid flow over a moving thin needle by considering Buongiorno’s nanofluid *** influences of Stefan blowing,Dufour and Soret effects are also considered in the *** equations which represent the described flow pattern are reduced to ordinary differential equations(ODEs)by using apt similarity transformations and then they are num.rically solved with runge–Kutta-Fehlberg’s fourth fifth-order method(rKF-45)with shooting *** impacts of pertinent parameters on thermal,mass and velocity curves are deliberated *** friction,rate of heat and mass transfer are also discussed *** reveal that,the increase in values of Brownian motion,thermophoresis,Dufour number,heating and radiative parameters im.roves the heat *** increasing values of the Schmidt number deteriorates the mass transfer but a converse trend is seen for increasing values of the Soret ***,the escalating values of the radiative parameter decays the rate of heat transfer.

关键词： moving thin needle Brownian motion and thermophoretic diffusion non-linear thermal radiation Stefan blowing condition

The analysis of composite laminated beams using a 2D interpolating meshless technique

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Acta mechanica Sinica 2018年第1期34卷 99-116页

作者： S.H.m.Sadek j.Belinha m.P.L.Parente r.m.Natal jorge j.m.A.césar de Sá A.j.m.Ferreira Department of mechanical Engineering Faculty of EngineeringUniversity of Porto Institute of mechanical Engineering and Industrial management University of Porto

Laminated composite materials are widely implemented in several engineering constructions. For its relative light weight, these materials are suitable for aerospace, military, m.rine, and automotive structural applications. To obtain safe and economical structures, the modelling analysis accuracy is highly relevant. Since meshless methods in the recent years achieved a rem.rkable progress in computational mechanics, the present work uses one of the most flexible and stable interpolation meshless technique available in the literature—the radial Point Interpolation method(rPIm).Here, a 2 D approach is considered to num.rically analyse composite laminated beams. Both the meshless formulation and the equilibrium equations ruling the studied physical phenomenon are presented with detail. Several benchm.rk beam examples are studied and the results are compared with exact solutions available in the literature and the results obtained from a comm.rcial finite element software. The results show the efficiency and accuracy of the proposed num.ric technique.

关键词： radial point interpolators rPIm Laminated beam meshless method

Analysis of Differences in Productivity,Profitability and Soil Fertility Between Organic and conventional cropping Systems in the Tropics and Sub-tropics

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journal of Integrative Agriculture 2014年第10期13卷 2299-2310页

作者： Te Pas c m.rees r m School of GeoSciences University of Edinburgh carbon management centre Scotland's Rural College

Organic farming aims to stimulate soil fertility by avoiding the use of synthetic fertiliser inputs, relying instead on locally available natural resources. It is regarded by many as a sustainable alternative to conventional fanning because it ensures higher biodiversity, restricts environmental pollution, prevents land degradation and is easy to apply for smallholder and subsistence farm.rs. Although widely practiced and studied in temperate regions, little is known about the potential overall benefits of organic farming in the tropics and subtropics. This paper addresses this gap by undertaking an analysis of the differences between organic and conventional agriculture in the tropics and sub-tropics based on an extensive literature review including 88 papers with 458 data pairs. The comparison is based on three main indicators： yield, gross m.rgin and soil organic carbon （SOc）. The differences between the organic and conventional systems for each of these main indicators is represented by the ratio of the value of the indicator in the organic system divided by the corresponding value in the conventional system. This was initially calculated for each data pair individually, and grouped by a variety of explanatory factors, such as precipitation, human development level, soil texture, crop type, organic input type, time after conversion and certification. The results demonstrate that under organic management, yields were on average 26% higher, gross m.rgins 51% higher and soil organic carbon 53% higher than under conventional management. The highest yield increases in organic cropping systems were achieved in the least developed countries, in arid regions and on coarse soils. For gross m.rgins, certification was the main reason for differences between organic and conventional systems. certified farm.rs, mostly located in developed countries, receive significantly higher prices. Furtherm.re, organic farming in the driest regions results in higher profits than in other

关键词： organic farming conventional fanning tropics subtropics carbon sequestration yield soil quality soil organic carbon