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Utilization of.the superior properties of.highly mesoporous PVP modif.ed NiCo_2O_4 with accessible 3D nanostructure and f.ower-like morphology towards electrochemical methanol oxidation reaction

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Journal of.Energy Chemistry 2019年第2期28卷 136-146页

作者： Gracita m.Tomboc medhen W.Abebe Anteneh f.Baye Hern Kim Department of.Energy Science and Technology Smart Living Innovation Technology CenterMyongji University

Up to this date,researchers are still f.cing dif.iculties to expand the technology of.direct methanol f.el cells(Dmf.s) because of.the high overpotential required to oxidize the methanol and its relatively poor perf.rmance due to CO poisoning of.the leading-high cost anode *** line with this,we have successf.lly modif.ed the morphological structure and composition of.low cost cobalt based-metal oxides,mCo_2O_4(m = Zn and Ni),with the simple and noble use of.polyvinyl pyrrolidone(PVP) as growth modif.er and surf.ce stabilizer during the synthesis of.nanoparticles in our previous reports,which shown high electrocatalytic activity and strong *** to the good perf.rmance of.our PVP modif.ed mCo_2O_4 towards pseudocapacitor and oxygen evolution reaction applications,we decided to extend our research study to methanol oxidation ***,PVP modif.ed Ni Co_2O_4 electrode directly grown on nickel f.am substrate via a simple hydrothermal process exhibited better perf.rmance compared with PVP modif.ed ZnCo_2O_4 and NiCo_2O_4 without *** had obtained a remarkably low onset potential of.0.285 V and high current density of.280 m A cm^(-2),and shown great stability and high poison tolerance during a continuous CV cycling and Chronoamperometry test,which attained high ef.iciency of.86.86%and 98.52%,*** positive results of.PVP modif.ed Ni Co_2O_4 electrode towards mOR might be attributed to its hierarchical 3 D nanostructures with highly mesoporous surf.ce and large surf.ce area which may have provided numerous electroactive sites,and the exceptional corrosion stability of.Ni Co_2O_4 electrode in alkaline solution.

关键词： NiCo2O4 3D nanostructure Electrochemical methanol oxidation Current density

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f.actographic analysis of.the overload ef.ect on f.tigue crack growth in 2024-T3 and 7075-T6 Al alloys

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International Journal of.minerals,metallurgy and materials 2020年第1期27卷 83-90页

作者： A.Albedah B.Bachir Bouiadjra S.m.A.K.mohammed f.Benyahia mechanical Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia LmPm Department of Mechanical EngineeringUniversity of Sidi Bel AbbesBP 89CitéBen M’hidiSidi Bel Abbes 22000Algeria Department of.mechanical and Industrial Engineering Ryerson UniversityTorontoOntario M5B 2K3Canada

The ef.ect of.single overload on the f.tigue crack growth in 2024-T3 and 7075-T6 Al alloys was *** tests under constantamplitude loading with overload peak were carried out on V-notched *** analysis was used as a principal approach to explain the crack growth retardation due to the *** electron microscopy(SEm)analyses were conducted on the f.actured surf.ce of.f.iled specimens to study the retardation *** obtained results show that the overload application generates a plastic zone in both aluminum *** generated plastic zone is three times larger in the case of.2024-T3 compared to 7075-T6,and thus,a signif.cant crack retardation was induced f.r *** retardation ef.ect due to the overload f.r 2024-T3 and 7075-T6 lasted f.r about 10 mm and 1 mm,respectively,f.om the point of.overload application.

关键词： f.tigue crack growth overload retardation f.actography crack tip plasticity

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multi-Objective Optimization Design through machine Learning f.r Drop-on-Demand Bioprinting

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Engineering 2019年第3期5卷 586-593页

作者： Jia Shi Jinchun Song Bin Song Wen f. Lu School of.mechanical Engineering and Automation Northeastern University Shenyang 110819 China Department of.mechanical Engineering National University of Singapore Singapore 119077 Singapore Singapore Institute of.manuf.cturing Technology Singapore 637662 Singapore

Drop-on-demand (DOD) bioprinting has been widely used in tissue engineering due to its highthroughput ef.iciency and cost ef.ectiveness. However, this type of.bioprinting involves challenges such as satellite generation, too-large droplet generation, and too-low droplet speed. These challenges reduce the stability and precision of.DOD printing, disorder cell arrays, and hence generate f.rther structural errors. In this paper, a multi-objective optimization (mOO) design method f.r DOD printing parameters through f.lly connected neural networks (f.NNs) is proposed in order to solve these challenges. The mOO problem comprises two objective f.nctions: to develop the satellite f.rmation model with f.NNs;and to decrease droplet diameter and increase droplet speed. A hybrid multi-subgradient descent bundle method with an adaptive learning rate algorithm (HmSGDBA), which combines the multisubgradient descent bundle (mSGDB) method with Adam algorithm, is introduced in order to search f.r the Pareto-optimal set f.r the mOO problem. The superiority of.HmSGDBA is demonstrated through comparative studies with the mSGDB method. The experimental results show that a single droplet can be printed stably and the droplet speed can be increased f.om 0.88 to 2.08 m·s^-1 af.er optimization with the proposed method. The proposed method can improve both printing precision and stability, and is usef.l in realizing precise cell arrays and complex biological f.nctions. f.rthermore, it can be used to obtain guidelines f.r the setup of.cell-printing experimental platf.rms.

关键词： Drop-on-demand printing Inkjet Gradient descent multi-objective optimization f.lly connected neural networks

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The embryology of.persistent cloaca and urogenital sinus malf.rmations

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Asian Journal of.Andrology 2020年第2期22卷 124-128页

作者： David f.m Thomas University of.Leeds LeedsWest Yorkshire LS29JTUK

Cloacal malf.rmations are characterized by the conf.uence of.the lower urinary tract,the f.male reproductive tract,and the rectum to create a common channel with a single opening on the *** presence of.a cloaca is a normal phase of.early human embryological *** the 4^th and 7^th weeks of.gestation,the cloaca undergoes subdivision to f.rm the hindgut and urogenital *** of.this process results in the congenital anomaly termed persistent cloaca(PC).The term urorectal septum malf.rmation sequence(URSmS)is also used to describe this *** classic description of.this process which is still cited in many standard textbooks dates f.om the 19th ***,this has been increasingly called into question by the f.ndings of.studies using modern scientif.c *** sinus anomalies are def.ned by the conf.uence of.the urethra and vagina to f.rm a common channel of.varying length with a single perineal *** this condition,the anorectal canal opens separately on the *** presence of.a urogenital sinus represents a transient phase of.the normal development of.the lower genital tract in the f.male ***,the f.rm of.urogenital sinus most commonly encountered in the developed world is a f.ature of.disordered sexual dif.erentiation and does not arise simply f.om the persistence of.the anatomical structure which is a f.ature of.normal f.tal development.

关键词： cloaca embryology urogenital sinus

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CRACK GROWTH BEHAVIOR AND f.ACTURE f.ATURE Of.GH2132 UNDER CREEP-f.TIGUE CONDITIONS

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Acta metallurgica Sinica(English Letters) 1997年第6期10卷 495-500页

作者： Geng, m.f. Luoyang Ship material Research Inst Luoyang China

The superalloy GH2132 is equivalent to A286. The tests were carried out at 550°C under various cyclic f.equencies (hold time) and load levels, and the f.acture surf.ces were examined by using a scanning electron microscope. It was shown that the f.acture mode of.creep-f.tigue and the ef.ect of.cyclic loading on crack growth change with the growth of.crack and the increase of.net-section stress, and both are reversed when the net-section stress is up to the yield stress of.material. When σn0.2, cracking is predominantly cyclic-dependent transgranular and cyclic loading accelerates creep crack growth, whereas when σn>σ0.2, the case is reversed.

关键词： Chromium alloys Crack propagation Creep f.acture Nickel alloys Rotating disks Superalloys

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micro-Structured f.ber Interf.rometer as Sensitive Temperature Sensor

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Photonic Sensors 2013年第3期3卷 208-213页

作者： f. C. f.VERO m. BECKER, R. SPITTEL m. ROTHHARDT J. KOBELKE H. BARTELT Institute of.Photonic Technology (IPHT) Albert-Einstein-Strafle-9 07745 Jena Germany

We report on a f.st and sensitive temperature sensor using a micro-structured or photonic crystal f.ber interf.rometer with a high germanium doped f.ber core. The wavelength sensitivity f.r temperature variation was as high as △λ/△T= 78 pm/℃ up to 500℃, which was 6 times more sensitive than the f.ber Bragg grating temperature sensitivity of.△λ/△TT= 13pm/℃ at 1550nm. The sensor device was investigated conceming the sensitivity characteristics and response time.

关键词： micro-structured optical f.ber f.ber interf.rometer f.ber temperature sensor

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f.rst Detailed Photometric Investigation on the Nature of.Contact Binary System AA Cet

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Research in Astronomy and Astrophysics 2023年第7期23卷 154-163页

作者： m.f.Yıldırım f.Soydugan Çanakkale Onsekiz mart University Astrophysics Research Center and Ulupınar Observatory17020ÇanakkaleTurkey Çanakkale Onsekiz mart University Faculty of SciencesDepartment of Physics17020ÇanakkaleTurkey

The TESS light curve(LC)of.the marginal contact binary A A Cet was analyzed simultaneously with the radial velocity and the orbital period(OP)change of.the system was *** physical parameters of.the system were obtained by analyzing the LC of.A A Cet with the Wilson-Devinney method,and the absolute parameters of.the components were calculated using the results *** the components of.AA Cet,the masses and radii were calculated as m_(1)=1.39±0.04 m_⊙,m_(2)=0.48±0.02 m_⊙,and R_(1)=1.64±0.03 R_⊙,R_(2)=1.01±0.04 R_⊙,*** Cet is a marginal contact binary with a temperature dif.erence of.1305 K between its components.A total of.14 eclipse times were obtained f.om the TESS data and used in the OP analysis together with those collected f.om the *** has been observed that the change in the OP of.AA Cet is in the f.rm of.a decreasing *** mass transf.r between the components has been interpreted as the reason f.r this *** OP decrease amount of.A A Cet was obtained as dP/dt=0.0062±0.0006 s yr^(-1).and the reason f.r this decrease was attributed to a 3.3(9)×10^(-8)m_⊙.mass transf.r per year f.om the more massive component to the less massive *** age of.A A Cet has been estimated as 7 Gyr,as the age of.contact systems helps us to understand their evolution.

关键词： (stars:)binaries:eclipsing stars:f.ndamental parameters stars:individual(AA Cet)

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Comparison of.structural diversity of.tree-crop associations in Peripheral and Buf.er zones of.Gachabari Sal f.rest area,Bangladesh

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Journal of.f.restry Research 2007年第2期18卷 23-26页

作者： m.m. Rahman H. Vacik f. Begum A. Nishad K.K. Islam Institute of.Silviculture University of Natural Resources and Applied Life SciencesViennaAustria Department of.Agronomy Bangladesh Agricultural UniversityMymensingh-2202. Bangladesh IUCN Bangladesh Department of.Agrof.restry Bangladesh Agricultural UniversityMymensingh-2202. Bangladesh

The structural diversity of.dif.erent tree-crop associations were studied at Gachabari Sal f.rest area of.madhupur Garh on Buf.er and Peripheral Zone during 2006. The total density, basal area of.trees in the Buf.er and Peripheral Zone were 155.5 trees·hm^(-2), 795.4 trees·hm^(-2) and 3.9 m2·hm-2, 5.8 m^2·hm^(-2), respectively. No regeneration and natural trees were f.und in Peripheral Zone and the Zone is totally occupied by exotic species where the Buf.er Zone comprised of.both natural and exotic trees. The Peripheral Zone belonged to younger and smaller trees whereas the Buf.er Zone belonged to mixture of.smaller, taller, younger and mature trees simultaneously. f.r the practicing of.dif.erent agrof.restry systems both Zones have lost their original characters of.Sal f.rest.

关键词： Structural diversity Tree-crop associations Sal Peripheral and Buf.er Zone.

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Best operating conditions to produce hydroxyapatite nanoparticles by means of.a spinning disc reactor

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f.ontiers of.Chemical Science and Engineering 2014年第2期8卷 156-160页

作者： A. f. D' Intino B. de Caprariis m.L. Santarelli N. Verdone A. Chianese Department of.Chemical Engineering Sapienza University via Eudossiana 00184 Rome Italy

In this work, mg2＋ doped hydroxyapatite （mg-HAP） nanoparticles were produced by a reactionprecipitation process by using a spinning disc reactor （SDR） at high rotational speed. The production process of.these nanoparticles consisted of.the neutralization reaction between two aqueous solutions of.calcium chloride and ammonia orthophosphate at room temperature. By operating at pH = 10, a high purity mg-HAP nanoparticles were obtained. In particular, they were 51 nm in average size when the two reagents were f.d over the disc symmetrically at 3 cm f.om the disc center and a rotational speed of.the disc reactor equal to 1400 r/min was adopted.

关键词： hydroxyapatite nanoparticles spinning discreactor

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Teleportation of.unknown states of.a qubit and a single-mode f.eld in strong coupling regime without Bell-state measurement

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Communications in Theoretical Physics 2023年第2期75卷 73-79页

作者： f.Jahanbakhsh m K Tavassoly Optics and Laser Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran

In this paper,we develop the teleportation scheme in[Zheng in Phys Rev A 69,064302,2004],in the sense that,we work in the strong atom-f.eld coupling regime wherein the rotating wave approximation(RWA)is no longer *** achieve the purpose,a scheme consisting of.a qubit interacting with a single-mode quantized f.eld is described via the Rabi model(counter rotation terms are taken into account).Our f.rst aim is to teleport an unknown atomic state of.a qubit(which interacts with the quantized f.eld in a cavity)to a second qubit(exists in another distant cavity f.eld),beyond the RWA and without the Bell-state measurement *** the continuation,in a similar way,we teleport an unknown state of.a single-mode f.eld *** f.ct,it is shown that,in this regime,af.er applying some particular conditions,containing the interaction time of.atom-f.eld in the cavities,adjusting the involved f.equencies,as well as the atom-f.eld coupling in the model,if.a proper measurement is perf.rmed on the state of.the f.rst qubit(the related f.eld in the cavity),the unknown states of.the qubit(f.eld)can be teleported f.om the f.rst qubit(cavity f.eld)to the second qubit(cavity f.eld),*** show that in both considered cases,the teleportation protocol is successf.lly perf.rmed with the maximum possible f.delity,1,and the acceptable success probability,0.25.

关键词： strong atom-f.eld coupling Rabi model quantum teleportation success probability f.delity

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