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Nitrogen and Carbon Isotope data of Olenekian to Anisian deposits from Kamenushka/South Primorye, Far-Eastern Russia and Their Palaeoenvironmental Significance

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Journal of Earth Science 2018年第4期29卷 837-853页

作者： Yuri d Zakharov micha Horacek Alexander m Popov Liana g Bondarenko Far Eastern geological Institute of Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia BLT Wieselburg Research Center HBLFA Francisco-Josephinum Wieselburg 3250 Austria Institute of Lithospheric Research Vienna University Vienna 1090 Austria

The Kamenushka Formation, exposed in the northern part of South Primorye （Kamennshka-1 and Kamenushka-2 sections）, is one of the few localities in the world with richly fossiliferous Lower-Upper Olenekian sedimentary successions. Lower to middle Triassic ammonoid-, brachiopod- and conodont-bearing silty-clayey deposits of the Kamenushka-1 and Kamenushka-2 sections have been isotope-geochemically investigated in detail. As a result, these sections, together with the previously investigated Abrek Section, exposed in the southern part of South Primorye, provide almost complete ^15Non- and ^13Corg- records for the Lower Triassic of this region. Nine N- isotope intervals and the five negative C-isotope excursions, reflecting, apparently, unstable climatic and hydrological conditions, have been distinguished in the Lower Triassic of South Primorye. On the basis of the new C-isotope data the mesohedenstroemia bosphorensis Zone （upper part）, Shimanskyites shimanskyi and Neocolumbites insignis zones of South Primorye are correlated now with the Lower Smithian part of the Yinkeng Formation, the Upper Smithian part of the Helongshan Formation and the middle Spathian part of the Nanlinghu Formation in South China, respectively, as has been observed in the Abrek, Kamenushka-2, West Pingdingshan and majiashan sections.

关键词： Triassic N- and C-isotopes palaeoclimatology bio- and chemostratigraphy Pri- morye Russia.

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Thermal Characteristics in the Cutting of Inconel 718 Superalloy Using CW Nd:YAg Laser

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Journal of materials Science & Technology 2010年第4期26卷 362-366页

作者： d.g. Ahn K.W. Byun m.C. Kang department of mechanical Engineering Chosun University 375 Seosuk-dong Dong-gu Gwang-ju 501-759 Korea Hybrid materials Solution National Core Research (NCRC) Pusan National University San 30 Changjeon-dong Keumjeong-gu Busan 609-735 Korea

The objective of the this study is to investigate the effects of cutting parameters on thermal characteristics, including practical cutting regions, the formation of the kerfwidth and the heat transfer phenomenon, in the cutting of Inconel 718 super-alloy sheets using a CW Nd：YAg laser. From the results of the experiments, the influence of process parameters on both the practical cutting region and the kerfwidth has been examined. In addition, it has been shown that the kerfwidth of the specimen lies in the range of 0.53-0.61 mm. In order to examine characteristics of the heat transfer during the laser cutting process, a three-dimensional quasi-steady heat transfer analysis has been performed using the commercial code SYSWELd V9.0. From the results of the analysis, the influence of cutting parameters on the temperature distribution in the vicinity of the cut section has been quantitatively evaluated. Based on these results, optimal cutting conditions have been estimated.

关键词： CW Nd:YAg laser Inconel 718 Kerfwidth Quasi-steady heat transfer analysis

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Inverse dynamics and servomotor parameter estimation of a 2-dOF spherical parallel mechanism

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Science China(Technological Sciences) 2008年第3期51卷 288-301页

作者： d g CHETWYNd School of Engineering The University of Warwick

A novel reconfigurable 5-dOF hybrid manipulator―TriVariant-B is composed of a 2-dOF spherical parallel mechanism which is serially connected with a 3-dOF open-loop kinematic chain undergoing one translation and two rotations by a prismatic joint. The merit of this design is that a relatively large workspace/limb- stroke ratio can be achieved thanks to the decomposition of the fixed point rotation and the relative translation. In this paper, on the basis of inverse dynamic formula- tion of the 2-dOF spherical parallel mechanism, an approach is proposed for esti- mating the servomotor parameters including moment of inertia, rated speed and the maximum torque in a quick manner. The approach has been employed for the development of a prototype for frame cutting process.

关键词： parallel kinematic machine inverse dynamics servomotor parameters

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具有潜在负热膨胀性和负压缩性的三角形构筑模块的有限元分析(英文)

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硅酸盐学报 2009年第5期37卷 743-748页

作者： grima Joseph N gATT Ruben ELLUL Brian 马耳他大学科学系马耳他MSD2080

研究了由3个梁焊接而成的三角形系统构成的二维单元的热膨胀和压缩特性,与每个梁相比,该三角形构件具有不同的性质(热膨胀和弹性模量)。结果表明:当三角形构件的底边热膨胀大于两侧边时,这种三角形系统可在一维方向上显示负热膨胀(即当... 详细信息

研究了由3个梁焊接而成的三角形系统构成的二维单元的热膨胀和压缩特性,与每个梁相比,该三角形构件具有不同的性质(热膨胀和弹性模量)。结果表明:当三角形构件的底边热膨胀大于两侧边时,这种三角形系统可在一维方向上显示负热膨胀(即当三角形梁以楔形结构形成时,会产生三角形缩短效应)和负压缩特性。更引起人们兴趣的是:线热膨胀特性与三角形构件的底边和侧边材料的相对刚性(弹性模量)有关。压力变化对这种构件存在影响。与侧边梁刚性相比,构件的线性压缩率变化与底边梁刚性存在主要关系。

关键词：可调热膨胀系数负热膨胀热收缩负压缩有限元法

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development of mucoadhesive sericin/alginate particles loaded with ibuprofen for sustained drug delivery

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Particuology 2018年第6期16卷 65-73页

作者： Emanuelle d.Freitas Jacyara m.m.Vidart Edson A.Silva meuris g.C.da Silva melissa g.A.Vieira department of Processes and Products design School of Chemical EngineeringUniversity of Campinas-UNICAMPAlbert Einstein Avenue50013083-852CampinasSPBrazil School of Chemical Engineering State University of West Parana-UNIOESTEFaculdade Street64585903-000ToledoPRBrazil

A sericin/alginate blend was successfully applied as a matrix for incorporation of *** provided a sustained release formulation,which could improve the therapeutic efficacy of ibuprofen and patient adherence to *** increased the proportion of drug incorporated into the particles (i.e., the drug incorporation efficiency),with incorporation rates between 73.01%±1.70%and 94.15%±4.21%. Alginate affected the drug release,and the particles with the maximum alginate mass fraction tested (2.8%)showed sustained release through a dissolution mechanism,reaching equilibrium after about *** of the incorporation efficiency and the drug release time showed the best results were for formulations with a high alginate *** electron microscopy,Fourier transform infrared spectroscopy,and X-ray diffraction analysis were used for particle characterization to study the incorporation of *** particle size range was 0.80±0.13to 1.08±*** size distributions of sericin-containing particles showed a good fit with the gaussian model.

关键词： Sericin Alginate Ibuprofen Sustained drug release

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EXPERImENTAL STUdY ON BEd RESISTANCE CHARACTERISTICS OF NONUNIFORm SEdImENT

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Journal of Hydrodynamics 2000年第4期12卷 66-74页

作者： Zhou, g.d. Liu, Q.Y. Wang, g.X. Hui, Y.J. Pang, d.m. Tsinghua Univ. Beijing 100084 China

Under natural circumstances, the bed of fluvial river is composed of nonuniform sediment, and its nonuniform property influences very much the bed resistance and flow characteristics. By using a one-dimensional laser velocimeter, flume experiments are carried out to analyze the resistance characteristics of open channel flow with the bed sediment composed of different representative particles and having different nonuniform properties. By means of separating factors, the factors affecting the bed resistance, including particle diameter, nonuniform property and flow conditions, are studied. A great number of laboratory test results and field data from other investigators have been analyzed.

关键词： Sediments

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Predicting maximum Lifespan Limits at mean menopausal Age

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Journal of mathematical Research with Applications 2025年第1期 133-142页

作者： m.SUmATHI S.ANTONY CARLA department of mathematics N.M.S.S.Vellaichamy Nadar College Research Scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

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dirac Points in Two-dimensional Inverse Opals

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Chinese Physics Letters 2013年第10期30卷 164-166页

作者： g.d.mahan department of Physics Pennsylvania State UniversityUniversity ParkPA 16802USA

The electron energy states and energy bands are calculated for a two-dimensional inverse opal *** that the opal structure is closed-packed circles,the inverse opal has the honeycomb *** honeycomb lattice in two dimensions has a diract *** properties can be manipulated by altering the structure of the inverse opal:the radius of the circle,and the small gap between circles.

关键词： structure inverse dirac

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Effect of Rotation Rate on microstructures and mechanical Properties of FSW mg-Zn-Y-Zr Alloy Joints

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Journal of materials Science & Technology 2011年第12期27卷 1157-1164页

作者： g.m. Xie Z.Y. ma Z.A. Luo P. Xue g.d. Wang The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 China Shenyang National Laboratory for materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

Friction stir welding （FSW） of mg-Zn-Y-Zr plates with 6 mm in thickness was successfully carried out under a wide range of rotation rates of 600-1200 r/rain with a constant traverse speed of 100 mm/min. After FSW, the coarse grains in the parent material （Pm） were changed into fine equiaxed recrystallized grains at the＇nugget zone （NZ）. Furthermore, the coarse mg-Zn-Y particles （W-phase） were broken up and dispersed homogenously into the mg matrix. With increasing rotation rates, the size of the W-phase particles at the NZ significantly decreased, but the recrystallized grain size tended to increase. The hardness values of the NZs for all the FSW joints were higher than those of the Pm, and the lowest hardness values were detected in the heat affected zone （HAZ）. The fracture occurred in the thermo-mechanical affected zone （TmAZ） on the advancing side for all the FSW joints in the tensile test, due to the incompatibility of the plastic deformation between the NZ and TmAZ caused by remarkably different orientation of grains and W-phase particles. The strength of FEW ioint reaches 90% of that of its Pm

关键词： Friction stir welding magnesium alloys microstructure mechanical property

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Positive mR and Large Temperature—Field Sensitivity in manganite Based Heterostructures

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Journal of materials Science & Technology 2013年第10期29卷 989-994页

作者： Uma Khachar P.S.Solanki R.J.Choudhary d.m.Phase d.g.Kuberkar department of Physics Saurashtra University UgCe-dAE Consortium for Scientifc Research

Studies on the ZnO/La0.5Pr0.2Sr0.3mn03 （LPSmO）/SrNb0.002Ti0.99803 （SNTO） heterostructure having varying thickness of p-type LPSmO （100 nm - LP1） and （200 nm - LP2） manganite are carried out. ZnO/LPSmO （n-p） and LPSmO/SNTO （p-n） junctions of both the heterostructures exhibit good rectifying behavior in a wide range of temperature and applied field. Forward and reverse bias characteristics of both the junctions of heterostructures show opposite behavior. The observation of negative magnetoresistance （mR） at 5 K and positive mR at 300 K, in both the heterostructures, has been explained in the context of interface region effects and filling of energy bands of LPSmO manganite. Further, at high temperature, the heterostructures exhibit large temperature （46%K-1） and field （40%T-1） sensitivities. dependence of transport, magnetotransport, I-V and sensing properties of the heterostructures, on the temperature, field and film thicknesses have been discussed in this communication.

关键词： Interfaces Thin films Pulsed laser deposition X-ray diffraction Electric properties

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