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Electron Acceleration by Microwave Radiation Inside a Rectangular Waveguide

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Plasma Science and Technology 2011年第3期13卷 357-361页

作者： b. f. MOHAMED A.M. GOUDA Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the f.elds associated with a transverse magnetic （TM） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations f.r an electron are solved, which was injected initially along the propagation direction of.the microwave. Expressions of.the acceleration gradient and def.ection angle are obtained. In principle, it is shown that the electron can be accelerated in this condition and there is no def.ection when the electron is injected f.om the centre of.the waveguide f.ont. However, it is f.und that the acceleration gradient and def.ection angle depend strongly on the parameters of.the microwave （intensity, f.equency, etc.） and the dimensions of.the waveguide.

关键词： waveguide electron acceleration polarized microwave

Interf.cial ef.ects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： f. J. Sabina A.b.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of.Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the ef.ects of.dispersion of.bloch-f.oquet waves. A particular attention is given to structures containing interf.ces between dissimilar media and localization of.the electrical f.elds near such interf.ces.

关键词： Piezoelectric periodic composites Interf.ces Dispersion of.bloch-f.oquet waves

Developmental and f.edf.rward Control of.the Expression of.f.late biosynthesis Genes in Tomato f.uit

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Molecular Plant 2010年第1期3卷 66-77页

作者： Jef.rey C. Wallera Tariq A. Akhtar Aurora Lara-Nunez Jesse f. Gregory lli Ryan R McQuinn James J. Giovannoni Andrew D. Hanson Horticultural Sciences Department University of Florida Gainesville FL 32611 USA f.od Science and Human Nutrition Department University of Florida Gainesville FL 32611 USA United States Department of.Agriculture-Agricultural Research Service and boyce Thompson Institute f.r Plant Research Ithaca NY 14853 USA

Little is known about how plants regulate their f.late content, including whether the expression of.f.late biosynthesis genes is orchestrated during development or modulated by f.late levels. Nor is much known about how f.late levels impact the expression of.other genes. These points were addressed using wild-type tomato f.uit and f.uit engineered f.r high f.late content. In wild-type f.uit, the expression of.genes specif.ing early steps in f.late biosynthesis declined during development but that of.other genes did not. In engineered f.uit overexpressing f.reign GTP cyclohy- drolase I and aminodeoxychorismate synthase genes, the expression of.the respective endogenous genes did not change, but that of.three downstream pathway genes--aminodeoxychorismate lyase, dihydroneopterin aldolase, and mitochondrial f.lylpolyglutamate synthase--respectively increased by up to 7.8-, 2.8-, and 1.7-f.ld, apparently in response to the build-up of.specif.c f.late pathway metabolites. These results indicate that, in f.uit, certain f.late pathway genes are developmentally regulated and that certain others are subject to f.edf.rward control by pathway intermediates. Micro- array analysis showed that only 14 other transcripts （of.11 000 surveyed） increased in abundance by two-f.ld or more in high-f.late f.uit, demonstrating that the induction of.f.late pathway genes is relatively specif.c.

关键词： f.late biosynthesis f.uit development metabolic engineering transcript prof.ling.

Ab-Initio Study of.Cobalt Impurity Ef.ects on Phonon Spectra, Mechanical and Thermal Properties of.Single Wall Carbon Nanotube （5,0）

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Chinese Physics Letters 2014年第4期31卷 110-113页

作者： H. Tashakori b. Khoshnevisan f. Kanjouri f.culty of.Physics University of Kashan Kashan Iran f.culty of.Physics Kharazmi University Karaj Iran

We use density f.nctional perturbation theory based on the pseudo-potential to calculate the phonon spectrum, phonon density of.states, specif.c heat capacity and mechanical properties of.pristine and cobalt doped （5,0） single wall carbon nanotube （CNT）. In the calculations, we consider one Co atom in the center of.the unit cell of.the tube and it is shown that the pristine （5~0） CNT is nonmagnetic while the Co-doped tube becomes magnetic. Young＇s modulus f.r both systems is about 1 TPa （＇af.er Co-doping it goes slightly higher） and the Poisson ratio f.r the pristine tube becomes quite a bit larger than the doped one. On the other hand, the calculated value of.radial breath mode f.r the pristine CNT is in good agreement with the experimental reports while af.er Co-doping it is increased. In addition, heat capacity of.the doped CNT is reduced, which leads to some important empirical applications.

关键词： Wall Carbon Nanotube Ab-Initio pseudo-potential

Use of.f.rricyanide f.r gold and silver cyanidation

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中国有色金属学会会刊：英文版 2009年第3期19卷 714-718页

作者： f. XIE D. b. D REISINGER Department of.Materials Engineering University of British Columbia

Low gold and silver leaching kinetics has been commonly observed in traditional gold-silver cyanidation process, especially in heap leaching and in situ leaching operations. The dif.erent mineralogy of.gold and silver in the ores is suspected to be the main reason, e.g., the occurrence of.low solubility acanthite (Ag2S) typically results in low overall silver extraction. Due to the low solubility of.oxygen in cyanide solution, the reactivity and availability of.oxidant is believed to be the critical limitation f.r gold and silver dissolution. The use of.f.rricyanide as the auxiliary oxidant f.r gold and silver cyanidation has been examined. The rotating disc test results prove the assistant ef.ect of.f.rricyanide on increasing the dissolution rate of.gold and silver. The potential use of.f.rricyanide in gold/silver cyanidation process is proposed based on the leaching results of.actual ores.

关键词：氰化工艺金银浸出动力学铁助氧化剂氰化物溶液旋转圆盘溶解度

Soil Pore Characterization Using f.ee Sof.ware and a Portable Optical Microscope

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Pedosphere 2013年第4期23卷 503-510页

作者： L. f. PIRES f. S. bORGES S. PASSONI A. b. PEREIRA Department of.Physics State University of Ponta Grossa (UEPG) Department of.Soil Science State University of Ponta Grossa (UEPG)

Total porosity （TP）, determined by image analysis, pore type and pore size distribution were evaluated on impregnated soil blocks f.om an undisturbed brazilian sandy loam soil using a digital portable optical microscope. The f.ee sof.ware Image J （version 1.40g） was used f.r image analysis. Procedures f.r soil image collection and analysis were presented. The image analysis allowed the evaluation of.pore sizes with diameters ranging f.om 20 to 〉 1 000 μm. The f.llowing types of.pores were also obtained： rounded, elongated and intermediate. The results M[owed the characterization of.the soil as moderately porous （TP = 21.6%）. Rounded, intermediate and elongated pores were responsible f.r 11.6%, 31.7% and 56.7% of.TP. In relation to pore size 51.1% of.TP was in the 100-500μm size class and a third of.TP came f.om the pores larger than 500μm.

关键词： image analysis soil porosity soil structure pore size distribution

f.rmation and Microstructural Characterization of.Silicon-modif.ed Aluminide Coating on Nickel-based Superalloy IN738LC

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材料热处理学报 2004年第05B期25卷 657-660页

作者： f. Shahriari f. Ashraf.zadeh A. Monshi Materials engineering department Isfahan University of Technology Isfahan IranMaterials engineering department Isfahan University of Technology Isfahan IranMaterials engineering department Isfahan University of Technology Isfahan Iran

In this investigation, aluminide coatings used to protect industrial components at high temperature and corrosive environments were modif.ed with silicon addition and the microstructural f.atures and f.rmation mechanism were evaluated. The coating on the nickel-based superalloy IN738LC was carried out by a two stage process including siliconizing at f.rst and aluminizing thereaf.er. Pack cementation siliconizing perf.rmed at 950C f.r 2, 4 and 6 hours in several powder mixtures of.Si, A12O3 and NHiCl, then aluminum was dif.used into the surf.ce of.the specimens by an industrial aluminizing process. The modif.ed coatings were characterized by means of.standard metallography, scanning electron microscopy, energy dispersive spectroscopy and X-ray dif.raction methods. The results show that Si in the coatings mainly presents in the f.rm of.secondary phases including Cr3Si, Mo5Si3 and Nii6Ti6Si7, well distributed within the NiAl matrix. The advantages of.this two stage modif.ed coating is discussed.

关键词：显微结构 IN738LC 镍超级合金扩散渗碳处理生长机制

Closed-f.rm solutions f.r f.ee vibration of.rectangular f.M thin plates resting on elastic f.undation

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Acta Mechanica Sinica 2016年第6期32卷 1088-1103页

作者： T. f. Xu Y. f. Xing Institute of.Solid Mechanics Beihang UniversityBeijing 100191 China China Academy of.Launch Vehicle Technology R&D Center Beijing 100076 China

This article presents closed-f.rm solutions f.r the f.equency analysis of.rectangular f.nctionally graded material (f.M) thin plates subjected to initially in-plane loads and with an elastic f.undation. based on classical thin plate theory, the governing dif.erential equations are derived using Hamilton's principle. A neutral surf.ce is used to eliminate stretching-bending coupling in f.M plates on the basis of.the assumption of.constant Poisson's ratio. The resulting governing equation of.f.M thin plates has the same f.rm as homogeneous thin plates. The separation-of.variables method is adopted to obtain solutions f.r the f.ee vibration problems of.rectangular f.M thin plates with separable boundary conditions, including, f.r example, clamped plates. The obtained normal modes and f.equencies are in elegant closed f.rms, and present f.rmulations and solutions are validated by comparing present results with those in the literature and f.nite element method results obtained by the authors. A parameter study reveals the ef.ects of.the power law index n and aspect ratio a/b on f.equencies.

关键词： f.nctionally graded material f.ee vibration Rectangular plate Close f.rm solutions Neutral surf.ce

Resonance Conversion as the Ef.ective Way of.Triggering the ^（178m2）Hf.Isomer Energy

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Chinese Physics Letters 2006年第8期23卷 2049-2051页

作者： f. f.odor KARPESHIN M. b.TRZHASKOVSKAYA 张景波 Science Center and Department of.Physics Harbin Institute of Technology Harbin 150001 f.ck Institute of.Physics St. Petersburg State University RU-198504 St. Petersburg Russia PNPI RU-198355 St. Petersburg Leningrad District Russia

Experiments on photo-induced de-excitation triggering of.^（178m2）Hf.are revisited. We present an alternative and more ef.ective way of.triggering by exploiting the resonance internal conversion. f.ll theoretical description of.a possible channel is presented. It is theref.re revisited the impact itself.produced by those experiments.

关键词： Resonance Conversion Ef.ective Way