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Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 191-216页

作者： D.v.DUNG D.t.DONG Faculty of Mathematics Mechanics and Informatics Vietnam National University Hanoi 100000 Vietnam Faculty of Civil Engineering University of Transport Technology Hanoi 100000 Vietnam

In this paper, the nonlinear analysis of stability of functionally graded ma- terial （FGM） sandwich doubly curved shallow shells is studied under thermo-mechanical loads with material properties obeying the general sigmoid law and power law of four ma- terial models. Shells are reinforced by the FGM stiffeners and rest on elastic foundations. theoretical formulations are derived by the third-order shear deformation theory （tSDt） with the von Karman-type nonlinearity taking into account the initial geometrical im- perfection and smeared stiffener technique. the explicit expressions for determining the critical buckling load and the post-buckling mechanical and thermal load-deflection curves are obtained by the Galerkin method. two iterat.v. algorithms are presented. the effects of the stiffeners, the thermal element, the distribution law of material, the initial imper- fection, the foundation, and the geometrical parameters on buckling and post-buckling of shells are investigated.

关键词： functionally graded material (FGM) sandwich double curved shallow shell,thermo-mechanical stability FGM stiffener elastic foundation

Electromagnetic diagnostics of composite materials

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广东有色金属学报 2005年第2期15卷 138-140页

作者： Fursa t.v. Surzhikov A.P. Khorsov N.N. tomsk Polytechnic University Tomsk 634034 Russia

It was studied the main regularities of mechanoelctric transformations in composites and developed electromagnetic methods of control of quality.

关键词：电磁诊断金属复合材料强度数值模型

Impact of lanthanum on the modification of HfO_2 films structure

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Journal of Rare Earths 2015年第8期33卷 857-862页

作者： t.P.Smirnova L.v.Yakovkina v.O.Borisov Nikolaev Institute of Inorganic Chemistry SB RAS

LaxHf1-xOy thin films with various concentrations of La, homogeneous and nonhomogeneous distributions of elements throughout the films thickness was purposefully grown by CvD. the composition of the films and their chemical structures were characterized throughout the films thickness by X-ray photoelectron spectroscopy （XPS） and energy-dispersive X-ray spectrometry （EDXA）. A full picture of the film crystallinity was provided by the combination of grazing incidence X-ray diffraction （GIXRD） synchrotron radiation （SR） and high resolution transmission electron microscopy （HR tEM）. It was shown that La acted as ＂molar volume modulator＂ and stabilized the nonequilibrium at t≤1300 ℃ cubic phases. the samples with La content in range of 7 at.%〈CLa〈22 at.% were materials with fluorite-type （Fm-3m） structure. the pyroehlore phase formation was observed at -18 at.% La content. the correlation between the La-doped content and the films microstructure was revealed.

关键词： Hf1-xLaxOy films solid solutions X-ray diffraction microstructure rare earths

Rescue from complications after pancreaticoduodenectomies at a low-volume Caribbean center:value of tailored peri-pancreatectomy protocols

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 681-688页

作者： Shamir O Cawich Elijah Dixon Parul J Shukla Shailesh v Shrikhande Rahul R Deshpande Fawwaz Mohammed Neil W Pearce Wesley Francis Shaneeta Johnson Johann Bujhawan Department of Surgery University of the West IndiesSt Augustine 000000Trinidad and Tobago Department of Surgery Faculty of MedicineUniversity of CalgaryCalgaryAlberta T2N2T9Canada Department of Surgery Weill Cornell Medical CollegeNew YorkNY 10065United States Department of Surgical Oncology Tata Memorial CenterHomi Bhabha National UniversityMumbai 400012India Department of Surgery Manchester Royal InfirmaryManchester M139WLUnited Kingdom University Surgical Unit Southampton General HospitalSouthampton SO166YDUnited Kingdom Department of Surgery University of the West IndiesNassau N-1184Bahamas Department of Surgery Morehouse School of MedicineAtlantaGA 30310United States Department of Surgery General Hospital in Port of SpainPort of Spain 000000Trinidad and Tobago

BACKGROUND Pancreaticoduodenectomy(PD)is a technically complex operation,with a re-lat.v.ly high risk for *** ability to rescue patients from post-PD complications is as a recognized quality *** protocols were instituted at our low volume facility in the year *** to document the rate of rescue from post-PD complications with tailored protocols in place as a measure of *** A retrospect.v. audit was performed to collect data from patients who experienced major post-PD complications at a low volume pancreatic surgery unit in trinidad and tobago between January 1,2013 and June 30,***-dardized definitions from the International Study Group of Pancreatic Surgery were used to define post-PD complications,and the modified Clavien-Dindo classification was used to classify post-PD *** Over the study period,113 patients at a mean age of 57.5 years(standard deviation[SD]±9.23;range:30-90;median:56)underwent PDs at this *** complications were recorded in 33(29.2%)patients at a mean age of 53.8 years(SD:±7.9).twenty-nine(87.9%)patients who experienced major morbidity were salvaged after aggre-ssive treatment of their ***(3.5%)died from bleeding pseudoaneurysm(1),septic shock secondary to a bile leak(1),anastomotic leak(1),and myocardial infarction(1).there was a significantly greater salvage rate in patients with American Society of Anesthesiologists scores≤2(93.3%vs 25%;P=0.0024).CONCLUSION this paper adds to the growing body of evidence that.v.lume alone should not be used as a marker of quality for patients requiring *** low volumes at our facility,we demonstrated that 87.9%of patients were rescued from major *** attributed this to several factors including development of rescue protocols,the competence of the pancreatic surgery teams and continuous,and adapt.v. learning by the entire institution,cul-minating in the development of tailored peri-pancreatectomy protoc

关键词： Pancreas Complication Rescue Failure Morbidity Mortality Pancreaticoduodenectomy

Influence of alkali metal doping on surface properties and catalytic act.v.ty/select.v.ty of CaO catalysts in oxidat.v. coupling of methane

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Journal of Natural Gas Chemistry 2008年第4期17卷 313-320页

作者： v.H.Rane S.t.Chaudhari v.R.Choudhary Chemical Engineering and Process Development Division National Chemical Laboratory

Surface properties （viz. surface area, basicity/base strength distribution, and crystal phases） of alkali metal doped CaO （alkali metal/Ca= 0.1 and 0.4） catalysts and their catalytic act.v.ty/select.v.ty in oxidat.v. coupling of methane （OCM） to higher hydrocarbons at different reaction conditions （viz. temperature, 700 and 750 ℃; CH4/O2 ratio, 4.0 and 8.0 and space velocity, 5140-20550 cm^3 ·g^-1·h^-1） have been investigated. the influence of catalyst calcination temperature on the act.v.ty/select.v.ty has also been investigated. the surface properties （viz. surface area, basicity/base strength distribution） and catalytic act.v.ty/select.v.ty of the alkali metal doped CaO catalysts are strongly influenced by the alkali metal promoter and its concentration in the alkali metal doped CaO catalysts. An addition of alkali metal promoter to CaO results in a large decrease in the surface area but a large increase in the surface basicity （strong basic sites） and the C2＋ select.v.ty and yield of the catalysts in the OCM process. the act.v.ty and select.v.ty are strongly influenced by the catalyst calcination temperature. No direct relationship between surface basicity and catalytic act.v.ty/select.v.ty has been observed. Among the alkali metal doped CaO catalysts, Na-CaO （Na/Ca = 0.1, before calcination） catalyst （calcined at 750 ℃）, showed best performance （C2＋ select.v.ty of 68.8% with 24.7% methane conversion）, whereas the poorest performance was shown by the Rb-CaO catalyst in the OCM process.

关键词： oxidat.v. coupling of methane alkali metal doped CaO catalysts basicity/base strength distribution catalytic act.v.ty/select.v.ty

Exploring the electromagnetic shielding behavior of lanthanum doped calcium nanoferrites

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Journal of Rare Earths 2024年第11期42卷 2128-2136页

作者： E.Ahilandeswari K.Sakthipandi R.Rajesh Kanna G.Rajkumar B.Ganesh Babu S.Arunmetha Aslam Hossain P.Sakthivel v.Rajendran M.Srinidhi Raghavan Department of Physics SRM TRP Engineering College Department of Electronics and Communication Engineering M. Kumarasamy College of Engineering Department of Physics Easwari Engineering College Department of Mechanical Engineering SRM TRP Engineering College Centre for Advanced Energy Studies Department of Electronics and Communication EngineeringKoneru Lakshmaiah Education Foundation Smart Materials Research Institute Southern Federal University Centre for Materials Science Department of PhysicsScience and HumanitiesFaculty of EngineeringKarpagam Academy of Higher Education Centre for Nanotechnology Academy of Maritime Education and Training (Deemed to be University) Department of Chemistry and Centre for Nano-Materials and Displays B.M.S. College of Engineering

the present study focuses on the synthesis and characterization of lanthanum(La3+)-doped calcium nanoferrites(CaLaxFe2-xO4:x=0.025,0.050,0.075 and 0.100) using the sonochemical *** techniques were employed to analyze the effect of La3+infusion,Raman spectroscopy confirms the presence of act.v. A1g,t2gand Egmodes in the CaLaxFe2-xO4nanoferrite,indicating the formation of an act.v. ferrite *** introduction of La3+doping results in a significant increase in the band gap energy,rendering the nanoferrites insulating（3.23-3,57 ev）.At higher frequencies,the impedance studies reveal minimal losses and better AC conduct.v.ty,pointing to improved dielectric *** higher frequencies,the Q-factor of La-doped calcium nanoferrites shows lower electromagnetic *** M-H curve exhibits ferromagnetic behavior,with La3+-doped calcium nano ferrites displaying a saturation magnetization ranging from 12.72 to 18.10 emu/*** incorporation of La3+also induces enhanced electrical polarization,leading to notable dielectric loss and increased absorption of electromagnetic ***,these CaLaxFe2-xO4nanoferrites demonstrate potential as effect.v. microwave absorbers across a wide frequency range,with significant shielding absorption observed at 8.8-9.1 GHz.

关键词： Dielectric Magnetism Microwave absorption Nanoferrites Rare earths Structural properties

Mechanical and thermal postbuckling of FGM thick circular cylindrical shells reinforced by FGM stiffener system using higher-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2017年第1期38卷 73-98页

作者： D.v.DUNG H.t.tHIEM Faculty of Mathematics Mechanics and InformaticsVietnam National UniversityHanoi 100000Vietnam

the postbuckling of the eccentrically stiffened circular cylindrical shells made of functionally graded materials （FGMs）, subjected to the axial compressive load and external uniform pressure and filled inside by the elastic foundations in the thermal environments, is investigated with an analytical method. the shells are reinforced by FGM stringers and rings. the thermal elements of the shells and stiffeners in the fundamental equations are considered. the equilibrium and nonlinear stability equations in terms of the displacement components for the stiffened shells are derived with the third-order shear deformation theory and Leckhniskii smeared stiffener technique. the closed-form expressions for determining the buckling load and postbuckling load-deflection curves are obtained with the Galerkin method. the effects of the stiffeners, the foundations, the material and dimensional parameters, and the pre-existent axial compressive and thermal load are considered.

关键词： stiffened cylindrical shell functionally graded material (FGM) postbuck- ling elastic foundation analytical

Study of the process e^+e^- →π^+π^-π~0π~0 at energies s～(1/2)<1 Gev

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Chinese Physics C 2010年第6期34卷 680-685页

作者： M.N.Achasov K.I.Beloborodov A.v.Berdyugin A.A.Bot.v.v.B.Golubev t.v.dimova v.P.Druzhinin L.v.Kardapoltsev A.G.Kharlamov D.P.Kovrizhin I.A.Koop A.A.Korol S.v.Koshuba A.E.Obrazovsky E.v.Pakhtusova D.A.Shtol S.I.Serednyakov Z.K.Silagadze A.N.Skrinsky Yu.A.tikhonov Yu.M.Shatunov A.v.vasil'ev Budker Institute of Nuclear Physics Russian Academy of Sciences Novosibirsk State University

In an experiment with the Spherical Neutral Detector at.v.PP-2M collider the cross section of the process e^＋e^- →π^＋π^-π^0π^0 was measured. At energies √s 〈 920 Mev this cross section was measured for the first time. the energy dependence of the cross section is well discribed by the vector dominance model with contributions from p, p＇, p＂ mesons. the decay probability ρ→π^＋π^-π^0π^0 was found to be Bρ = （1.60±0.74±0.18） × 10^-5. the upper limit for the decay ω→π^＋π^-π^0π^0 was improved by two orders of magnitude compared to the previous measurements and is Bω 〈 2 × 10^-4 at 90% confidence level.

关键词： vEPP-2M spherical neutral detector meson decay

声致发光: 红外受激辐射放大(IRaser)?(英文)

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南京大学学报（自然科学版） 1998年第1期34卷 102-107页

作者：普列文斯里克t.v. Discovery Bay 香港

声致发光（ＳＬ）以Ｐｌａｎｃｋ理论来处理是将空泡看作为微型可变调谐红外受激辐射放大，当空崩裂时将红外辐射转变为可见光子．在ＩＲａｓｅｒ腔内，红外辐射被吸收并再发射回到腔内，其时间间隔满足ＩＲａｓｅｒ壁间的半波边界条件... 详细信息

声致发光（ＳＬ）以Ｐｌａｎｃｋ理论来处理是将空泡看作为微型可变调谐红外受激辐射放大，当空崩裂时将红外辐射转变为可见光子．在ＩＲａｓｅｒ腔内，红外辐射被吸收并再发射回到腔内，其时间间隔满足ＩＲａｓｅｒ壁间的半波边界条件，约为１飞秒量级．此时，空泡壁的Ｐｌａｎｃｋ能量的增量约为２０～１０μｅＶ量级，由于红外吸收相继累积达到可见光子能级，然后在约～１００ｐｓ量级时间内再发射，由此解释观察到皮秒脉冲间隔的声致发光．Ｐｌａｎｃｋ能量增量只能激发依附在ＩＲａｓｅｒ壁上的水分子或其他分子的转动模式，由此解释了为什么在声致发光谱中没有观察到无转动模式的惰性气体的谱线．在冰点时声致发光增加可由水的低蒸气压来解释．反之，在高温时ＳＬ熄灭．估计空泡中的平均可见光子数、功率和光子能量可以从单一崩裂的ＳＬ空泡作出合理的解释．

关键词：声致发光普朗克理论红外受激辐射 IRaser

Electrodeposition of aluminium and aluminium-copper alloys from a room temperature ionic liquid electrolyte containing aluminium chloride and triethylamine hydrochloride

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 909-916页

作者： P.v. Suneesh t.G. Satheesh Babu t. Ramachandran Department of Sciences Amrita School of Engineering Amrita Vishwa Vidyapeetham Amritanagar P. O.Coimbatore - 641112India

the electrodeposition of A1 and A1-Cu binary alloys on to gold substrates from a room temperature ionic liquid electrolyte containing A1C13-EtaNHC1 was studied. the electrochemical behavior of the electrolyte and the mechanism of deposition were investigated through cyclic voltammetry （Cv）, and the properties of deposits obtained were assessed by scanning electron microscopy with energy dispersive X-ray spectroscopy （SEM-EDS） and X-ray diffraction （XRD）. A1 of 70μm in thickness and an A1-Cu alloy of 30μm in thickness with 8at% copper were deposited from the electrolyte. SEM images of the deposits indicate that the A1 deposit was smooth and uniform, whereas the Al-Cu deposit was nodular. the average crystalline size, as determined by XRD patterns, was found to be （30±5） and （29±5） nm, respect.v.ly, for A1 and A1-Cu alloys. Potentiodynamic polarization （tafel plots） and electrochemical impedance spectroscopic （EIS） measurements showed that Al-Cu alloys are more corrosion resistant than Al.

关键词： electrodeposition aluminium copper alloys ionic liquids triethylamine hydrochloride copper acetylacetonate