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Ef.ects of.Magnet Size and Geometry on Magnetic Levitation f.rce

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Chinese Physics Letters 2007年第9期24卷 2664-2666页

作者： M. K. Alqadi H. M. Al-khateeb f. y. Alzoubi N. y. Ayoub Department of.Physics Jordan University of Science and Technology Irbid Jordan School of.Natural Applied Sciences German Jordanian University Amman Jordan

We obtain analytical relations f.r the levitation f.rce as a f.nction of.dimensions of.the superconductor-magnet system. The f.rce has been calculated on the basis of.the dipole-dipole interaction model. The ef.ect of.thickness of.the superconductor on the levitation f.rce is investigated. The results show that the inf.uence of.geometry and thickness of.the magnet becomes signif.cantly large at small levitation distances. f.rthermore, approximating the permanent magnet as a point dipole results in an inaccurate estimation of.the levitation f.rce.

关键词： MEISSNER STATE

A hybrid method to select morphometric f.atures using tensor completion and f.score rank f.r gif.ed children identif.cation

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Science China(Technological Sciences) 2021年第9期64卷 1863-1871页

作者： ZHANG Jin f.NG f.n HAN Tianyi DUAN f.ng SUN Zhe CAIAf. Cesar f. SOLÉ-CASALS Jordi College of.Computer Science Nankai UniversityTianjin 300350China Department of.Artif.cial Intelligence Nankai UniversityTianjin 300350China Computational Engineering Applications Unit Head Office for Information Systems and CybersecurityRIKEN351-0198 SaitamaJapan Instituto Argentino de Radioastronomía-CCT La Plata CONICET/CIC-PBA/UNLP1894 V.ElisaArgentina Department of.Psychiatry University of CambridgeCambridge CB20SZUnited Kingdom Data and Signal Processing Group University of Vic-Central University of Catalonia08500 VicCataloniaSpain

Gif.ed children are able to learn in a more advanced way than others, probably due to neurophysiological dif.erences in the communication ef.iciency in neural pathways. Topological f.atures contribute to understanding the correlation between the brain structure and intelligence. Despite decades of.neuroscience research using MRI, methods based on brain region connectivity patterns are limited by MRI artif.cts, which theref.re leads to revisiting MRI morphometric f.atures, with the aim of.using them to directly identif. gif.ed children instead of.using brain connectivity. However, the small, high-dimensional morphometric f.ature dataset with outliers makes the task of.f.nding good classif.cation models challenging. To this end, a hybrid method is proposed that combines tensor completion and f.ature selection methods to handle outliers and then select the discriminative f.atures. The proposed method can achieve a classif.cation accuracy of.93.1%, higher than other existing algorithms, which is thus suitable f.r the small MRI datasets with outliers in supervised classif.cation scenarios.

关键词： gif.ed children identif.cation morphometric f.atures tensor completion f.ature selection

Ef.ECT Of.LOW-f.EQUENCy ELECTROMAGNETIC f.ELD ON THE AS-CASTING MICROSTRUCTURES AND MECHANICAL PROPERTIES Of.HDC 2024 ALUMINUM ALLOy

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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 205-210页

作者： Q.f. Zhu Z.H. Zhao J.Z. Cui y.B. Zuo f. Qu Key Laboratory of.Electromagnetic Processing of.Materials Ministry of Education Northeastern Univer- sity Shenyang 110004 China

The inf.uences of.the low f.equency electromagnetic f.eld on the horizontal direct chill casting process were investigated experimentally. Ingots of.2024 aluminum alloy with a cross size of.40 mm× 200 mm were produced by the conventional horizontal chill casting process and low f.equency electromagnetic horizontal chill casting processre- spectively. The as-cast structures and the mechanical property of.the ingots were examined. The results showed that the low f.equency electromagnetic f.eld could sub- stantially ref.ne the microstructures and pronouncedly reduce the macrosegregation in the horizontal direct chill casting process. Moreover, the surf.ce quality of.the ingot was prominently improved by the low f.equency electromagnetic f.eld. The f.acture strength and elongation percentage of.the ingot was increased with the low f.equency electromagnetic f.eld.

关键词： Horizontal direct chill casting Low f.equency electromagnetic f.eld 2024 aluminum alloy Microstructures Macrosegregation

Uncertainty relations f.r general phase spaces

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f.ontiers of.physics 2016年第3期11卷 51-60页

作者： Reinhard f. Werner Institut f.ir Theoretische Physik Leibniz Universitiit Hannover Germany

We describe a setup f.r obtain!ing uncertainty relations f.r arbitrary pairs of.observables related by a f.urier transf.rm. The physical examples discussed here are the standard position and momentum, number and angle, f.nite qudit systems, and strings of.qubits f.r quantum inf.rmation applications. The uncertainty relations allow f.r an arbitrary choice of.metric f.r the outcome distance, and the choice of.an exponent distinguishing, e.g., absolute and root mean square deviations. The emphasis of.this article is on developing a unif.ed treatment, in which one observable takes on values in an arbitrary locally compact Abelian group and the other in the dual group. In all cases, the phase space symmetry implies the eciuality of.measurement and preparation uncertainty bounds. There is also a straightf.rward method f.r determining the optimal bounds.

关键词： uncertainty relations phase space measurement uncertainty

Kinetics of.the Reaction of.2-Chloro-3,5-dinitrobenzotrif.ouride with Aniline in Toluene and Methanol-Toluene Mixed Solvents

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Chinese Journal of.Chemistry 2012年第1期30卷 109-114页

作者： f.thalla Magda f. Chemistry Department Faculty of ScienceAlexandria UniversityP.O.426 IbrahimiaAlexandria 21321Egypt

Kinetics of.the reaction of.2-chloro-3,5-dinitrobenzotrif.ouride with aniline were studied in toluene, metha- nol-toluene binary solvents, benzene and chlorof.rm. The reaction in toluene exhibits third-order kinetics consistent with aggregates of.aniline. Thermodynamic parameters AH#, AS# and AG# are calculated and discussed f.r the reaction of.2-chloro-3,5-dinitrobenzotrif.ouride with aniline in methanol-toluene. Molecular complexes between aniline and the substrate are rejected spectrophotometricaly. The mechanism is studied and compared with the reac- tion in presence of.pyridine. It shows an amine dependence and f.rmation of.homo and/or hetero mixed aggregates between aniline and pyridine i.e. dimer mechanism.

关键词： kinetics 2-chloro-3,5-dinitrobenzotrif.ouride methanol-toluene

Multiscale stochastic f.nite element method on random f.eld modeling of.geotechnical problems- a f.st computing procedure

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f.ontiers of.Structural and Civil Engineering 2015年第2期9卷 107-113页

作者： Xi f. XU School of.Civil Engineering Beo'ing Jiaotong University Beijing 100044 China

The Green-f.nction-based multiscale stochastic f.nite element method (MSf.M) has been f.rmulated based on the stochastic variational principle. In this study a f.st computing procedure based on the MSf.M is developed to solve random f.eld geotechnical problems with a typical coef.icient of.variance less than 1. A unique f.st computing advantage of.the procedure enables computation perf.rmed only on those locations of.interest, theref.re saving a lot of.computation. The numerical example on soil settlement shows that the procedure achieves signif.cant computing ef.iciency compared with Monte Carlo method.

关键词： multiscale f.nite element settlement perturbation random f.eld geotechnical

Early stages of.non-classic crystal growth

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Science China Chemistry 2011年第12期54卷 1867-1876页

作者： GREER Heather f. EaStChem School of ChemistryUniversity of St Andrews

Investigation of.early stages of.crystal growth revealed that crystal growth in some systems may not f.llow the classic *** the early stages of.inorganic crystal growth,precursor molecules and/or nanocrystallites may aggregate into large and disordered particles with the assistance of.some polymers or *** crystallization of.these aggregates would then take place to f.rm shells with high crystallinity and density,f.llowed by an extension of.the crystallization f.om surf.ce to *** so-called reversed crystal growth mechanism has been f.und in crystallization of.several inorganic compounds including zeolites,perovskites,metals and metal oxides,and will be identif.ed in more material *** establishment of.this new crystal growth route gave us more f.eedom to control the morphology of.crystals and to understand the f.rmation mechanism of.many natural *** article gives a brief.review of.the recent research in this f.eld by f.aturing some typical examples of.the reversed crystal growth.

关键词： reversed crystal growth hollow crystals core-shell particles electron microscopy

f.rtif.cation Challenges and Needs

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Biomedical and Environmental Sciences 2001年第1期14卷 98-103页

作者： RODOLf. f. f.ORENTINO President Philippine Association of Nutrition Philippines

Experience in many parts of.the developing world has shown that f.od f.rtif.cation of.ers a cost_ef.ective and sustainable solution to the problem of.micronutrient malnutrition. Building on the advances in science and technology and backed by studies on the economic benef.ts of.f.rtif.cation programs, governments and industry are beginning to respond positively to the call of.nutrition advocates to adopt f.rtif.cation as a long_term strategy. On the other hand, f.rmidable challenges still remain in many countries in Asia, constraining the widespread adoption of.this strategy. The science and technology community needs to provide adequate scientif.c and technological inf.rmation as basis f.r planning and decision making. The government f.ces the challenge of.providing the enabling environment f.r all stakeholders to cooperate in the f.rtif.cation ef.ort. Industry f.ces the challenge of.adapting its production system to the requirements of.f.rtif.cation in order that they can contribute to social objectives while pursuing their economic objectives. The international and bilateral aid agencies need to seek tried and innovative ways to support the multiple players of.f.od f.rtif.cation, as these players in turn f.ce the challenges that conf.ont them.

关键词： Developing Countries f.od Industry f.od f.rtif.ed Asia f.od Technology Humans Nutrition Disorders Public Health

Spray f.eeze drying of.small nucleic acids as inhaled powder f.r pulmonary delivery

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Asian Journal of.Pharmaceutical Sciences 2018年第2期13卷 163-172页

作者： Wanling Liang Alan y.L.Chan Michael y.T.Chow f.ona f.K.Lo yingshan Qiu Philip C.L.kwok Jenny K.W.Lam Department of.Pharmacology and Pharmacy Li Ka Shing Faculty of Medicine The University of Hong Kong Advanced Drug Delivery Group Faculty of Pharmacy The University of Sydney

The therapeutic potential of.small nucleic acids such as small interf.ring RNA(siRNA) to treat lung diseases has been successf.lly demonstrated in many in vivo studies. A major barrier to their clinical application is the lack of.a saf. and ef.icient inhaled *** this study, spray f.eeze drying was employed to prepare dry powder of.small nucleic *** and herring sperm DNA were used as bulking agent and model of.small nucleic acid therapeutics, respectively. f.rmulations containing dif.erent solute concentration and DNA concentration were produced. The scanning electron microscope(SEM) images showed that the porosity of.the particles increased as the solute concentration decreased. Powders prepared with solute concentration of.5% w/v were f.und to maintain a balance between porosity and robustness. Increasing concentration of.DNA improved the aerosol perf.rmance of.the f.rmulation. The dry powder f.rmulation containing 2% w/w DNA had a median diameter of.12.5 μm, and the aerosol perf.rmance study using next generation impactor(NGI) showed an emitted f.action(Ef. and f.ne particle f.action(f.f. of.91% and 28% respectively. This f.rmulation(5% w/v solute concentration and 2% w/w nucleic acid) was adopted subsequently to produce siRNA powder. The gel retardation and liquid chromatography assays showed that the siRNA remained intact af.er spray f.eeze drying even in the absence of.delivery vector. The siRNA powder f.rmulation exhibited a high Ef.of.92.4%and a modest f.f.of.around 20%. f.rther exploration of.this technology to optimise inhaled siRNA powder f.rmulation is warranted.

关键词： Inhalation Pulmonary delivery Small interf.ring RNA Spray f.eeze drying