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Tuning the selectivity of natural oils and fatty acids/esters deoxygenation to biofuels and fatty alcohols:A review

Green Energy & Environment 2023年第3期8卷 722-743页

作者： Yingdong Zhou Javier Remon Zhicheng Jiang Avtar s.Matharu Changwei Hu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan 610064China Instituto de Carboquímica CSICZaragoza50018Spain Department of Biomass science and Engineering Sichuan UniversityChengdu610064China National Engineering Research Center of Clean Technology in Leather Industry Sichuan UniversityChengdu610064China Green Chemistry Centre of Excellence Department of ChemistryUniversity of YorkHeslingtonYorkYO105DDUK

The chemical transformation of natural oils provides alternatives to limited fossil fuels and produces compounds with added value for the chemical *** selective deoxygenation of natural oils to diesel-ranged hydrocarbons,bio-jet fuels,or fatty alcohols with controllable selectivity is especially attractive in natural oil feedstock *** review presents recent progress in catalytic deoxygenation of natural oils or related model compounds(e.g.,fatty acids)to renewable liquid fuels(green diesel and bio-jet fuels)and valuable fatty alcohols(unsaturated and saturated fatty alcohols).Besides,it discusses and compares the existing and potential strategies to control the product selectivity over heterogeneous *** research conducted and reviewed has only addressed the production of one category;therefore,a new integrative vision exploring how to direct the process toward fuel and/or chemicals is urgently ***,work conducted to date addressing the development of new catalysts and studying the influence of the reaction parameters(e.g.,temperature,time and hydrogen pressure)is summarized and critically discussed from a green and sustainable perspective using efficiency indicators(e.g.,yields,selectivity,turnover frequencies and catalysts lifetime).special attention has been given to the chemical transformations occurring to identify key descriptors to tune the selectivity toward target products by manipulating the reaction conditions and the structures of the ***,the challenges and future research goals to develop novel and holistic natural oil biorefineries are *** a result,this critical review provides the readership with appropriate information to selectively control the transformation of natural oils into either biofuels and/or value-added *** new flexible vision can help pave the wave to suit the present and future market needs.

关键词： Natural oil Deoxygenation Controllable selectivity Biofuels Fatty alcohols

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Laser Induced Fluorescence spectroscopy of IrN

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Chinese Journal of Chemical Physics 2009年第2期22卷 157-161页

作者： H. F. Pang A. s. C. Cheung Department of Chemistry The University of Hong Kong Pokfulam Road Hone Kong China

High resolution laser induced fluorescence, spectra of IrN in the spectral region between 394 and 520 nm were recorded using laser vaporization/reaction free jet expansion and laser induced fluorescence spectroscopy. seven new vibronic transition bands were observed and analyzed. Two Ω=1 and five Ω=0 new states were identified. Least squares fit of rotationally resolved transition lines yielded accurate molecular constants for the upper states. spectra of isotopic molecules were observed, which provided confirmation for the vibrational assignment. Comparison of the observed electronic states of IrB, IrC, and IrN provides a good understanding of the chemical bonding of this group of molecules.

关键词： Electronic transition Rotational analysis Iridium mononitride Laser induced fluorescence spectroscopy

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Three-to-one internal resonance in multiple stepped beam systems

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Applied Mathematics and Mechanics(English Edition) 2009年第9期30卷 1131-1142页

作者： A. Tekin E. zkaya s. M. Bagdatlh Technical Vocational school of Higher Education Celal Bayar University Department of Mechanical Engineering Celal Bayar University

In this study, the vibrations of multiple stepped beams with cubic nonlinearities are considered. A three-to-one internal resonance case is investigated for the system. A general approximate solution to the problem is found using the method of multiple scales （a perturbation technique）. The modulation equations of the amplitudes and the phases are derived for two modes. These equations are utilized to determine steady state solutions and their stabilities. It is assumed that the external forcing frequency is close to the lower frequency. For the numeric part of the study, the three-to-one ratio in natural frequencies is investigated. These values are observed to be between the first and second natural frequencies in the cases of the clamped-clamped and clamped-pinned supports, and between the second and third natural frequencies in the case of the pinned-pinned support. Finally, a numeric algorithm is used to solve the three-to-one internal resonance. The first mode is externally excited for the clamped-clamped and clamped-pinned supports, and the second mode is externally excited for the pinned-pinned support. Then, the amplitudes of the first and second modes are investigated when the first mode is externally excited. The amplitudes of the second and third modes are investigated when the second mode is externally excited. The force-response, damping-response, and .frequency- response curves are plotted for the internal resonance modes of vibrations. The stability analysis is carried out for these plots.

关键词： stepped beam three-to-one internal resonance stability analysis nonlinear vibration perturbation method

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Protective effect of Irsogladine on monochloramineinduced gastric mucosallesions in rats:a comparative study with rebamipide

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World Journal of Gastroenterology 1999年第6期5卷 477-482页

作者： H Yamamoto, M Umeda, H Mizoguchi, s Kato and K Takeuchi Kyoto Phamaceutical University 日本

AIM To examine the effect of irsogladine, a novel antiulcer drug, on the mucosal ulcerogenic response to monochloramine (NH 2Cl) in rat stomach, in comparison with rebamipide, another antiulcer drug with cytoprotective activity. METHODs AND REsULTs Oral administration of NH 2Cl (120*!mM) produced severe hemorrhagic lesions in unanesthetized rat stomachs. Both irsogladine ( 1*!mg/*!kg - 10*!mg/*!kg , po ) and rebamipide ( 30*!mg/*!kg - 100*!mg/*!kg , po ) dose dependently prevented the development of these lesions in response to NH 2Cl, the effect of irsogladine was significant at 3*!mg/*!kg or greater, and that of rebamipide only at 100*!mg/*!kg . The protective effect of irsogladine on NH 2Cl induced gastric lesions was significantly reduced by N G nitro L arginine methyl ester (L NAME) but not by indomethacin, while that of rebamipide was significantly mitigated by indomethacin but not by L NAME. Topical application of NH 2Cl (20*!mM) caused a marked reduction of potential difference (PD) in ex vivo stomachs. This PD reduction was not affected by mucosal application of irsogladine, but significantly prevented by rebamipide. The mucosal exposure to NH 4OH (120*!mM) also caused a marked PD reduction in the ischemic stomach (bleeding from the carotid artery), resulting in gastric lesions. These ulcerogenic and PD responses caused by NH 4OH plus ischemia were also significantly mitigated by rebamipide, in an indomethacin sensitive manner, while irsogladine potently prevented such lesions without affecting the PD response, in a L NAME sensitive manner. CONCLUsION These results suggest that ① NH 2Cl generated either exogenously or endogenously damages the gastric mucosa, ② both irsogladine and rebamipide protect the stomach against injury caused by NH 2Cl, and ③ the mechanism underlying the protective action of irsogladine is partly mediated by endogenous nitric oxide, while that of rebamipide is in part mediated by endogenous prostaglandins.

关键词： irsogladine rebamipide monochloramine gastric mucosal lesions rats comparative study

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sea Urchin spines as a Model-system for Permeable,Light-Weight Ceramics with Graceful Failure Behavior. Part I. Mechanical Behavior of sea Urchin spines under Compression

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Journal of Bionic Engineering 2009年第4期6卷 203-213页

作者： V.Presser s.schultheiB C.Berthold K.GNickel Institute

The spines of pencil and lance urchins Heterocentrotus mammillatus and Phyllacanthus imperialis were studied as a model of light-weight material with high impact *** complex and variable skeleton construction ('stereom') of body and spines of sea urchins consists of highly porous Mg-bearing calcium *** basically brittle material with pronounced single-crystal cleavage does not fracture by spontaneous catastrophic device failure but by graceful failure over the range of tens of millimeter of bulk compression *** was observed in bulk compression tests and blunt indentation experiments on regular,infiltrated and latex coated sea urchin spine *** characterization was carried out using X-ray computer tomography,optical and scanning electron *** behavior is interpreted to result from the hierarchic structure of sea urchin spines from the rnacroscale down to the *** derived from this study see ceramics with layered porosity as a possible biomimetic construction for appropriate applications.

关键词： sea urchin urchin spines biominmitic mechanical behavior compression calcite

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Formation of radially expanding liquid sheet by impinging two round jets

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Applied Mathematics and Mechanics(English Edition) 2010年第8期31卷 937-946页

作者：王志亮 s．P．LIN 周哲玮 shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 P. R. China Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY 13699 USA

A thin circular liquid sheet can be formed by impinging two identical round jets against each other. The liquid sheet expands to a certain critical radial distance and breaks. The unsteady process of the formation and breakup of the liquid sheet in the ambient gas is simulated numerically. Both liquid and gas are treated as incompressible Newtonian fluids. The flow considered is axisymmetric. The liquid-gas interface is modeled with a level set function. A finite difference scheme is used to solve the governing Navier-stokes equations with physical boundary conditions. The numerical results show how a thin circular sheet can be formed and break at its circular edge in slow motion. The sheet continues to thin as it expands radially. Hence, the Weber number decreases radially. The Weber number is defined as ρu 2 h/σ, where ρ and σ are, respectively, the liquid density and the surface tension, and u and h are, respectively, the average velocity and the half sheet thickness at a local radial location in the liquid sheet. The numerical results show that the sheet indeed terminates at a radial location, where the Weber number reaches one as observed in experiments. The spatio-temporal linear theory predicts that the breakup is initiated by the sinuous mode at the critical Weber number We c =1, below which the absolute instability occurs. The other independent mode called the varicose mode grows more slowly than the sinuous mode according to the linear theory. However, our numerical results show that the varicose mode actually overtakes the sinuous mode during the nonlinear evolution, and is responsible for the final breakup. The linear theory predicts the nature of disturbance waves correctly only at the onset of the instability, but cannot predict the exact consequence of the instability.

关键词： flow instability level set method interfacial flow liquid jet

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On the Voltage and Frequency Distribution of Dielectric Properties and ac Electrical Conductivity in Al/siO_(2)/p-si (MOs) Capacitors

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Chinese Physics Letters 2013年第1期30卷 165-168页

作者： Ahmet Kaya Şemsettin Altındal YaseminŞafak Asar Zekayi sönmez Department of Physics Faculty of SciencesGazi University06500AnkaraTurkey

An Al/siO_(2)/p-si(MOs)capacitor with a thick(826Å)interfacial oxide layer(siO_(2))which is formed by using the thermal oxidation method is fabricated to investigate both frequency and applied bias voltage dependences of real and imaginary parts of dielectric constant(ϵ'andϵ")and electric modulus(M'and M"),loss tangent(tanδ)and ac electrical conductivity(σ_(ac))in a wide frequency range from 1 kHz to 1 MHz at room *** dielectric properties of the MOs capacitor are obtained using the forward and reverse bias capacitance-voltage(C–V)and conductance-voltage(G/ω–V)measurements in the applied bias voltage range 1.4–5.6 *** values ofϵ',ϵ",tanδ,M',M"and σ_(ac) are found to be strong functions of frequency and applied bias voltage in the depletion region due to excess capacitance Cex and conductance G_(ex)/ω especially at low *** experimental results show that the interfacial polarization can occur at low frequencies more easily,consequently contributing to the dispersion inϵ',ϵ",tanδ,M',M"and σ_(ac) values of the MOs *** other reason for dispersion in the dielectric properties may be attributed to a particular density distribution of interface states(Nss)localized at the si/siO_(2) interface,as well as space charge carriers and inhomogeneity of interfacial oxide *** increase in conductivity with increasing frequency can be attributed to the hopping type conduction *** can be concluded that theϵ',ϵ",tanδ,M',M"and σ_(ac) values of the Al/siO_(2)/p-si(MOs)capacitor are strongly dependent on both the frequency and applied bias voltage especially in the depletion region.

关键词： polarization dielectric interfacial

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Nuclear structure and decay modes of Ra isotopes within an axially deformed relativistic mean field model

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Chinese Physics C 2018年第8期42卷 121-129页

作者： Rashmirekha swain s.K.Patra B.B.sahu school of Applied sciences KIIT Deemed to be UniversityBhubaneswar-751024OdishaIndia Institute of Physics Bhubaneswar-751005India

We examine the structural properties and half-life decay of Ra isotopes within the axially deformed Relativistic Mean-Field（RMF）theory with NL3 force *** work out the binding energy（BE）,RMs radii,two-neutron separation energies（s（2n））,and some other *** results are in good agreement with the finite-range droplet model（FRDM）and experimental *** the possibility of neutron magic number,theα-decay and cluster decay half-lives of Ra isotopes are calculated systematically using the Q-values obtained from the RMF *** decay half-life calculations are carried out by taking three different empirical *** calculated decay half-lives are found to be highly sensitive to the choice of *** shell or sub-shell closures are found at daughter nuclei with N=128 and N=126 when alpha and 8Be,12C,18O respectively are emitted from Ra *** the cluster radioactivity is affected by the shell closure of parent and daughter,a long half-life indicates the stability of the parent,and a small parent half-life indicates that the shell stability of the daughter against decay.

关键词： relativistic mean field nuclear bulk properties alpha and cluster decay half-life

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sULPHONATED POLY ETHER ETHER KETONE/POLYVINYL ALCOHOL/PHOsPHOTUNGsTIC ACID COMPOsITE MEMBRANEs FOR PEM FUEL CELLs

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Chinese Journal of Polymer science 2009年第2期27卷 157-164页

作者： s.Guhan N.Arun Kumar D.sangeetha Department of Chemistry Anna University

Composite membranes with polyvinyl alcohol (PVA),sulphonated poly ether ether ketone (sPEEK) and phosphotungstic acid (PWA) were prepared using solvent casting *** proton conductivities of such membranes were found to be in the order of 10^(-3) s/cm in the fully hydrated condition at room temperature as measured by impedance *** crystalline properties were studied by X-ray diffraction *** thermal properties were determined by TGA and DsC *** tensile strength and perce...

关键词： PVA sPEEK PWA Conductivity Composite membranes.

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Electrostatic Nonplanar Positron-Acoustic shock Waves in superthermal Electron-Positron-Ion Plasmas

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Communications in Theoretical Physics 2015年第6期63卷 754-760页

作者： M.J.Uddin M.s.Alam A.A.Mamun Department of Physics Jahangirnagar University

The basic properties of the nonlinear propagation of the nonplanar （cylindrical and spherical） positronacoustic （PA） shock waves （sHWs） in an unmagnetized electron-positron-ion （e-p-i） plasma containing immobile positive ions, mobile cold positrons, and superthermal （kappa distributed） hot positrons and electrons are investigated both analytically and numerically. The modified Burgers equation （roBE） is derived by using the reductive perturbation method. The basic features of PA sHWs are significantly modified by the cold positron kinematic viscosity （U）, superthermal parameter of electrons （ke）, superthermal parameter of hot positrons （kp）, the ratio of the electron temperature to hot positron temperature （or）, the ratio of the electron number density to cold positron number density （μe）, and the ratio of the hot positron number density to cold positron number density （μph）. This study could be useful to identify the basic properties of nonlinear electrostatic disturbances in dissipative space and laboratory plasmas.

关键词： positron-acoustic waves superthermal particles Kappa distribution shock waves modified Burg-ers equation electron-positronion plasmas

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