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An ecofriendly approach for corrosion control of 6061 Al-15%(v)SiC(p)composite and its base alloy

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Chinese Journal of Chemical Engineering 2017年第3期25卷 363-372页

作者： Charitha b.p. padmalatha Rao Department of chemistry Manipal Institute of TechnologyManipalUdupiKamatakaIndia

Corrosion inhibition characteristics of bio polymer dextran was studied for the corrosion control of 6061 Al-15%_((v)) SiC_((p)) composite and its base alloy in 1 mol·L^(-1) HCl. Standard electrochemical techniques such as potentiodynamic polarization(pDp) measurements and electrochemical impedance spectroscopy(EIS) method were adopted for corrosion rate measurement. Surface morphology was studied by scanning electron microscopy(SEM) and elemental mapping was done by energy dispersive X-ray(EDX) analysis. Suitable mechanism was proposed for corrosion and inhibition process. Results indicated that dextran acts as an excellent anticorrosive agent for the corrosion control of 6061 Al-15%_((v)) SiC_((p)) composite, with maximum inhibition efficiency of 91% for the concentration of 0.4 g·L^(-1) at 303 K. Dextran acted as a mixed type of inhibitor, and got physically adsorbed both on composite and base alloy by obeying Langmuir adsorption isotherm. Dextran is proved to be a green inhibitor with environmental and economic benefits.

关键词： 6061 Al-15%(v) SiC(p) composite Green inhibitor biopolymer Electrochemical studies SEM–EDX

Quasielastic Electron Scattering from ^(12)C

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Chinese physics Letters 1997年第5期14卷 321-324页

作者： LU pao b.p.Nigam Department of physics and Astronomy Arizona State UniversityBox 871504TempeAZ 85287-1504U.S.A National Center of High performance Computing P.O.Box 19-136Hsim ChuTaiwan

Transverse electron scattering response function S_(T)(q,ω)has been calculated by using a hard core common harmonic oscillator *** agreement is obtained with the experimental date at q=400 MeV/c.

关键词： potential. Electron harmonic

Electrical properties of rare earth based tungsten bronze vanadates

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Journal of Rare Earths 2012年第11期30卷 1134-1137页

作者： b.b.Mohanty p.S.Sahoo R.N.p.Choudhary Department of physics Betnoti College Betnoti Department of physics ITER

barium based tungsten bronze （Tb） oxides having high dielectric constant and low loss, can be effectively used as transducers, actuators, capacitors and also in memory devices. All these characteristics stimulated the researchers to replace toxic and hazardous lead based materials by barium based Tb materials from industry. In the present research work, polycrystalline samples of baaSrRTi3VTO30 （R=Dy, Sm, La） were synthesized by a high temperature solid state reaction technique. preliminary structural （X-ray diffraction） analyses of these com- pounds showed the formation of single-phase orthorhombic structures at room temperature having average crystallite size of the order of some nanometer for all the compounds. The scanning electron micrographs （SEM） provided information on the quality of the samples and showed more or less homogeneous distribution of grains over the entire surface of the samples. Detailed dielectric study in a wide temperature range （30-500 ℃） showed ferro to para phase transition for Dy and Sm substituted samples whereas no such transition was observed for La substituted samples. both the grain and grain boundary resistances exhibited negative temperature coefficient of resistance behavior much like semiconductors. The dc conductivity of all the compounds obeyed Arrhenius relation.

关键词： ceramics X-ray diffraction dielectric properties electrical conductivity rare earths

Efficient up-conversion photoluminescence in all-inorganic lead halide perovskite nanocrystals

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Nano Research 2020年第7期13卷 1962-1969页

作者： Andres Granados del Aguila TThu ha Do Jun Xing Wen Jie Jee Jacob b.Khurgin Qihua Xiong Division of physics and Applied physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Key Laboratory of Eco-Chemical Engineering Ministry of EducationCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Department of Electrical and Computer Engineering Johns Hopkins UniversityBaltimoreMaryland 21218USA State Key Laboratory of Low-Dimensional Quantum physics Department of PhysicsTsinghua UniversityBeijing 100084China

Up-conversion photoluminescence(UCpL)refers to the elementary process where low-energy photons are converted into high-energy ones via consecutive interactions inside a *** additional energy is provided by intermnal thermal energy in the form of lttice vibrations(phonons),the process is called phonon-assisted ***,we report the exceptionally large phonon-assisted energy gain of up to^8kgT(kg is boltzmann constant,T is temperature)on all-inorganic lead halide perovskite semiconductor colloidal nanocrystals that goes beyond the maximum capabilty of only harvesting optical phonon *** systematic optical study in combination with a statistical probability model,we explained the nontrivial phonon-assisted UCpL process in perovskites nanocrystals,where in addition to the strong electron-phonon(light-matter)coupling,other nonlinear processes such as phonon-phonon(matter-matter)interaction also effectively boost the up-conversion efficiency.

关键词： up-conversion photoluminescence phonons lead halide perovskite colloidal nanocrystals

A novel benzo[4,5]furo[3,2-d]pyrimidine-based host as a n-type host for blue phosphorescent organic light-emitting diodes

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Science China Materials 2022年第4期65卷 1028-1033页

作者： Junsu ha Junseop Lim Jun Yeob Lee School of Chemical Engineering Sungkyunkwan University2066Seobu-roJangan-guSuwon-siGyeonggi-do16419Republic of Korea

An electron-transport-type host was synthesized using a benzo[4,5]furo[3,2-d]pyrimidine(bFp)core to develop a high triplet energy *** host was designed to have both the tetraphenylsilyl blocking group and the hole-transport-type carbazole *** the device application,the host was used as an electron-transport-type host mixed with a hole-transport-type 3,3'-di(9H-carbazol-9-yl)-1,1†-biphenyl(mCbp)host in the blue phosphorescent organic light-emitting diodes(phO-LEDs)doped with a[[5-(1,1-dimethylethyl)-3-phenyl-1H-imidazo[4,5-b]pyrazin-1-yl-2(3H)-ylidene]-1,2-phenylene]bis-[[6-(1,1-dimethylethyl)-3-phenyl-1H-imidazo[4,5-b]pyrazin-1-yl-2(3H)-ylidene]-1,2-phenylene]iridium(Ir(cb)3)blue *** a result,the mCbp:CzbFpmSi mixed host showed high external quantum efficiency over 20%at 1000 cd m^(−2) and low efficiency roll-off in the blue phOLEDs.

关键词： blue device host efficiency lifetime

A study of mining fatalities and coal price variation

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International Journal of Mining Science and Technology 2019年第4期29卷 599-602页

作者： p.Knights b.Scanlan School of Mechanical and Mining Engineering The University of Queensland

It has long been postulated that a relationship exists between commodity price cycles and fatalities in the mining *** studies have found only weak correlations in this *** study analyses the fatalities recorded in coal mines over the period 1985-2016 in the State of Queensland as a function of thermal coal price *** study finds that the relationship between fatalities and coal prices is not *** to two fatalities occur in most years independent of the thermal coal *** the price of coal falls below AUD 55/tonne(non-inflation adjusted),the likelihood of an incident involving multiple fatalities *** probability can be estimated at 2 in 18 events(equivalent to 11%).This paper postulates that in difficult economic times,mining companies react by downsizing direct *** not carefully managed,this can result in loss of knowledge around safety systems,and reduced effectiveness of safety *** of labour cost advantages,some jobs previously undertaken by direct employees will be replaced by *** contractor numbers contribute to increased risk of fatalities occurring,as contractors are over-represented in accident categories involving vehicle accidents,tire handling and crushing *** inspectorates,mining,and mining contractor companies need to be especially vigilant to enforce health and safety management systems during periods of low coal prices.

关键词： Coal mining fatalities Coal prices Queensland Australia

Significance of age and comorbidity as prognostic indicators for patients with bladder cancer

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Asian Journal of Andrology 2010年第5期12卷 766-774页

作者： Moon Soo ha In Ho Chang Department of Urology College of Medicine Chung-Ang University Seou1140-75 7 Korea

The aim of this study was to determine the impact that age and comorbidity status have on both overall and bladder cancer-specific survival of bladder cancer patients. We obtained medical information pertaining to a population of 528 patients with newly diagnosed bladder cancer from Chung-Ang University Hospital cancer registry. The Adult Comorbidity Evaluation-27 （ACE-27） test, which has been previously validated in adult cancer patients, was used to assess comorbidity. We evaluated differences in the demographic and clinical characteristics of included patients, as well as differences in the treatments they received after categorizing them by age. The median age at the time of bladder cancer diagnosis of the entire cohort was 63 years, and the median follow-up time was 97 months. Of the 528 patients who were included in our study, 303 had at least one comorbid condition and 249 died during the follow-up period. When patients were stratified by age, we found that older patients had a higher proportion of severe comorbidities （p 〈 0.01） than younger patients, and that a lower proportion of them underwent radical cystec- tomy for invasive bladder cancer （IbC）（p 〈 0.01）. by multivariate analysis, we found that older age was predictive of lower overall survival （OS） and bladder cancer-specific survival （bCSS） rates among patients with superficial bladder cancer （SbC） and of lower OS rates among patients with IbC. We also found that moderate-severe comorbidity status and treatment through a bladder-conserving approach were predictive of lower OS and cancer-specific survival rates among patients with IbC. The disparity between overall deaths and bladder cancer deaths was shown in SbC and increased along with age and higher comorbidity. Age and comorbidity were found to be independent predictive factors of OS and bCSS among bladder cancer patients, and explained the disparity that we observed between overall bladder cancer-specific mortality rates.

关键词： age comorbidity neoplasm prognostic indicator urinary bladder

Inertia-Centric Stability Analysis of a planar Uniform Dust Molecular Cloud with Weak Neutral-Charged Dust Frictional Coupling

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plasma Science and Technology 2014年第5期16卷 433-447页

作者： p.K.KARMAKAR b.bORAH Department of physics Tezpur University

This paper adopts an inertia-centric evolutionary model to study the excitation mechanism of new gravito-electrostatic eigenmode structures in a one-dimensional（1-D） planar self-gravitating dust molecular cloud（DMC） on the Jeans scale.A quasi-neutral multi-fluid consisting of warm electrons,warm ions,neutral gas and identical inertial cold dust grains with partial ionization is *** grain-charge is assumed not to vary at the fluctuation evolution time *** neutral gas particles form the background,which is weakly coupled with the collapsing grainy plasma *** gravitational decoupling of the background neutral particles is justifiable for a higher inertial mass of the grains with higher neutral population density so that the Jeans mode frequency becomes reasonably *** physical basis is the Jeans assumption of a self-gravitating uniform medium adopted for fiducially analytical simplification by neglecting the zero-order ***,the equilibrium is justifiably treated initially as ＂homogeneous＂.The efficacious inertial role of the thermal species amidst weak collisions of the neutral-charged grains is taken into account.A standard multiscale technique over the gravito-electrostatic equilibrium yields a unique pair of Korteweg-de Vries（KdV） *** is integrated numerically by the fourth-order Runge-Kutta method with multi-parameter variation for exact shape ***,the model is conducive for the propagation of new conservative solitary spectral *** basic physics,parametric features and unique characteristics are *** results go qualitatively in good correspondence with the earlier observations made by *** applications relevant to space and astrophysical environments are concisely highlighted.

关键词： molecular cloud pair KdV equations solitary patterns

Graphs of NMS Flows on S^3 with Knotted Saddle Orbits and No Heteroclinic Trajectories

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2213-2224页

作者： b.CAMpOS p.VINDEL Dpt.Matemàtiques Universitat JaumeI

We consider NMS systems on S^3 without heteroclinic trajectories connecting two saddles orbits and we build the dual graphs associated with this kind of flows. We prove that flows coming from essential attachments of ... 详细信息

关键词： NMS systems Wada operations dual graphs