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Study of.the Reaction of.5-Aryl-7-hydrazino-2-phenylpyra- zolo[1,5-c]pyrimidines with 1,3-Dicarbonyl Compounds

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Chinese Journal of.Chemistry 2011年第11期29卷 2451-2460页

作者： Atta, Kamal f. M. Chemistry Department Faculty of Science Alexandria University lbrahimia P. O. Box 426 Alexandria 21321 Egypt

A novel synthetic method f.r the preparation of.5-aryl-7-（3,5-dimethyl-lH-pyrazol-l-yl）-2-phenylpyra- zolo[1,5-c]-pyrimidines and 1-（5-aryl-2-phenylpyrazolo[1,5-c]pyrimidin-7-yl）-3-methyl-lH-pyrazol-5-ols is provided by condensative cyclization of.5-aryl-7-hydrazino-2-phenylpyrazolo[1,5-c]pyrimidines with 1,3-dicarbonyl compounds. The study of.the more reactive position f.r electrophilic substitusion reactions on such ring system was also achieved.

关键词： cyclization electrophilic substitution pyrazolylpyrazolopyrimidine IR NMR mass spectrometry

Can Heavier Liquid f.oat on Top of.a Lighter One？

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Chinese Physics Letters 2011年第1期28卷 127-129页

作者： A. H. Ayyad f. Takrori Department of.Chemistry Faculty of Science and Technology Hebron University P.O. Box 40 Hebron West Bank Palestine

We report on a f.rst observation of.a f.oating- spherical Hg （density 13g/cm3） drop on top of.a glycerin （density 1.26g/cm3） drop, the latter is hemispherical and about f.ur times larger in volume. This observation is clearly against nature＇s gravity law and has never been reported bef.re. Here we present spectacular high resolution photos that clearly demonstrate this remarkable f.oating phenomenon. Using milli-Q water, the Hg drop would stay down adhered at the triple line. Instead, the coincidental use of.tap water displays the same phenomenon. Increasing the volume of.the supporting liquid to a certain value causes the Hg drop to sink. A 5-M NaCl aqueous solution is f.und enough to show the same f.oating phenomenon. This f.oating mercury as a phenomenon is puzzling. On this length scale it seems that surf.ce tension and curvature dominate over gravity.

关键词： Sof. matter liquids and polymers f.uid dynamics Surf.ces interf.ces and thin f.lms

Improving Solution of.Euler Equations by a Gas-Kinetic BGK Method

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西北工业大学学报 2009年第1期27卷 1-5页

作者： Liu, Ya Gao, Chao Liu, f. National Key Laboratory of.Aerodynamic Design and Research Northwestern Polytechnical University Xi'an 710072 China Department of.Mechanical and Aerospace Engineering University of California Irvine CA 92697-3975 United States

*** well known JST(Jameson-Schmidt-Turkel) scheme requires the use of.a dissipation *** propose using gas-kinetic BGK(Bhatnagar-Gross-Krook) method,which is based on the more f.ndamental Boltzmann equation,in order to obviate the use of.dissipation term and obtain,we believe,an improved *** 1 deals essentially with three things:(1) as analytical solution of.molecular probability density f.nction at the cell interf.ce has been obtained by the Boltzmann equation with BGK model,we can compute the f.ux term by integrating the density f.nction in the phase space;eqs.(8) and(11) require caref.l attention;(2) the integrations can be expressed as the moments of.Maxwellian distribution with dif.erent limits according to the analytical solution;eqs.(9) and(10) require caref.l attention;(3) the discrete equation by f.nite volume method can be solved using the time marching *** are perf.rmed by the BGK method f.r the Sod′s shock tube problem and a two-dimensional shock ref.ection *** results are compared with those of.the conventional JST scheme in f.gs.1 and *** BGK method provides better resolution of.shock waves and other f.atures of.the f.ow f.elds.

关键词： Euler equations Boltzmann equation gas-kinetic BGK(Bhatnagar-Gross-Krook) scheme JST(Jameson-Schmidt-Turkel) scheme shock tube shock ref.ection

Bound states of.the Dirac equation with position-dependent mass f.r the Eckart potential

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Chinese Physics B 2013年第1期22卷 62-67页

作者： Bahar M. K. Yasuk f. Department of.Physics Erciyes University Department of.Physics Karamanoglu Mehmetbey University

Studying with the asymptotic iteration method, we present approximate solutions of.the Dirac equation f.r the Eckart potential in the case of.position-dependent mass. The centrif.gal term is approximated by an exponen... 详细信息

关键词： Dirac equation position-dependent mass Eckart potential asymptotic iteration method

Coupling Analysis of.Multiple Machine Learning Models f.r Human Activity Recognition

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Computers, Materials & Continua 2024年第6期79卷 3783-3803页

作者： Yi-Chun Lai Shu-Yin chiang Yao-chiang Kan Hsueh-Chun Lin Department of.Public Health China Medical UniversityTaichung406040Taiwan Department of.Inf.rmation and Telecommunications Engineering Ming Chuan UniversityGui-ShanTaoyuan333Taiwan Department of.Electrical Engineering Yuan Ze UniversityChung-Li32003Taiwan Department and Institute of.Health Service Administrations China Medical UniversityTaichung406040Taiwan

Artif.cial intelligence(AI)technology has become integral in the realm of.medicine and healthcare,particularly in human activity recognition(HAR)applications such as f.tness and rehabilitation *** study introduces a robust coupling analysis f.amework that integrates f.ur AI-enabled models,combining both machine learning(ML)and deep learning(DL)approaches to evaluate their ef.ectiveness in *** analytical dataset comprises 561 f.atures sourced f.om the UCI-HAR database,f.rming the f.undation f.r training the ***,the MHEALTH database is employed to replicate the modeling process f.r comparative purposes,while inclusion of.the WISDM database,renowned f.r its challenging f.atures,supports the f.amework’s resilience and *** ML-based models employ the methodologies including adaptive neuro-f.zzy inf.rence system(ANf.S),support vector machine(SVM),and random f.rest(Rf.,f.r data *** contrast,a DL-based model utilizes one-dimensional convolution neural network(1dCNN)to automate f.ature ***,the recursive f.ature elimination(Rf.)algorithm,which drives an ML-based estimator to eliminate low-participation f.atures,helps identif. the optimal f.atures f.r enhancing model *** best accuracies of.the ANf.S,SVM,Rf.and 1dCNN models with meticulous f.aturing process achieve around 90%,96%,91%,and 93%,*** analysis using the MHEALTH dataset showcases the 1dCNN model’s remarkable perf.ct accuracy(100%),while the Rf.SVM,and ANf.S models equipped with selected f.atures achieve accuracies of.99.8%,99.7%,and 96.5%,***,when applied to the WISDM dataset,the DL-based and ML-based models attain accuracies of.91.4%and 87.3%,respectively,aligning with prior research *** conclusion,the proposed f.amework yields HAR models with commendable perf.rmance metrics,exhibiting its suitability f.r integration into the healthcare services system through AI-driven applications.

关键词： Human activity recognition artif.cial intelligence support vector machine random f.rest adaptive neuro-f.zzy inf.rence system convolution neural network recursive f.ature elimination

A comparative study of.semi-active control strategies f.r base isolated buildings

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Earthquake Engineering and Engineering Vibration 2015年第3期14卷 487-502页

作者： Oliveira f. Morais P. Suleman A. National Laboratory f.r Civil Engineering (LNEC) Av. do Brasil 101 1700-066 Lisbon Portugal Scholarship HolderPh D CandidateMSc National Laboratory f.r Civil Engineering (LNEC) Av. do Brasil 101 1700-066 Lisbon Portugal Researcher Ph D University of.Victoria Dep. Mechanical Engineering PO Box 1700 Stn CSC Victoria BC V8W 2Y2 Canada Professor Ph D PEng

A comparative analytical study of.several control strategies f.r semi-active(SA) devices installed in baseisolated buildings aiming to reduce earthquake induced vibrations is *** f.rce tracking schemes comprising a linear controller plus a 'clipped' algorithm and a nonlinear output f.edback controller(NOf.) are considered to tackle this *** controllers include the integral controller(I),the linear quadratic regulator(LQR) and the model predictive controller(MPC).A single degree-of.f.eedom system subjected to input accelerograms representative of.the Portuguese seismic actions are f.rst used to validate and evaluate the f.asibility of.these *** obtained results show that structural systems using SA devices can in general outperf.rm those equipped with passive devices f.r lower f.ndamental f.equency structural systems,namely base-isolated *** ef.ectiveness of.the proposed strategies is also evaluated on a 10 storey base-isolated dual f.ame-wall *** f.rce tracking scheme with an integral controller outperf.rms the other three as well as the original structure and the structure equipped with passive devices.

关键词： semi-active control integral controller linear qua

Combined Ef.ect of.Magnetic f.eld and Thermal Dispersion on a Non-Darcy Mixed Convection

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Journal of.Thermal Science 2011年第3期20卷 276-282页

作者： M. f. EI-Amin Shuyu Sun Computational Transport Phenomena Laboratory （CTPL） Division of Physical Sciences and Engineering （PSE）King Abdullah University of Science and Technology （KAUST） Thuwal 23955-6900 Jeddah Kingdom of Saudi Ara-bia Mathematics Department Faculty of Science South Valley University Aswan 81528 EGYPT

This paper is devoted to investigate the inf.uences of.thermal dispersion and magnetic f.eld on a hot semi-inf.nite vertical porous plate embedded in a saturated Darcy-f.rchheimer-Brinkman porous medium. The coef.icient of.thermal dif.usivity has been assumed to be the sum of.the molecular dif.usivity and the dynamic dif.usivity due to mechanical dispersion. The ef.ects of.transverse magnetic f.eld parameter (Hartmann number Ha), Reynolds number Re (dif.erent velocities), Prandtl number Pr (dif.erent types of.f.uids) and dispersion parameter on the wall shear stress and the heat transf.r rate are discussed.

关键词： Thermal dispersion non-Darcy convection magneto-hydro-dynamics porous media geothermal systems

AITEB - An European Research Project on Aero-thermodynamics of.Turbine Endwalls and Blades

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Journal of.Thermal Science 2004年第2期13卷 97-108页

作者： f. HASELBACH H.-P. SCHIf.ER Rolls-Royce Deutschland Turbines Eschenweg 11 15827 Dahlewitz GermanyRolls-Royce Deutschland Turbines Eschenweg 11 15827 Dahlewitz Germany

The paper delivers an overview on the European research project AITEB - Aerothermal Investigations on Turbine Endwalls and Blades, which started in year 2000 in the course of.the 5. f.amework Programme (GROWTH). The aim is to submit an integrated technology and design tool package f.r the advanced, aerothermal highly loaded design of.turbines, especially: Experimental/numerical investigation on heat transf.r and f.lm-cooling in separated f.ow f.r highly loaded blades including advanced trailing edge cooling Heat transf.r/ improved cooling of.turbine endwalls: Experimental/numerical work on cooling of.turbine endwalls, shrouds and recessed blade tips. Optimised Cf.-process (drawing-grid-modelling-postprocessing-risk assessment) in order to derive the 'best practice' to use Cf. as a time ef.ective tool. Af.er most of.the project lif., an overview on the project is delivered. Experimental results of.test series at various test sites are compared to numerical simulations of.the industrial and university partners.

关键词： turbines aerothermal endwalls blades cooling-technology experiment Cf..

Inf.uence of.PtMo Structure and Composition on the Adsorption Energies, Adsorption Site and Vibrational f.equency of.Carbon Monoxide

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Chinese Journal of.Structural Chemistry 2007年第7期26卷 843-849页

作者：吉智 Abraham f. Jalbout 李俊篯 Department of.Chemistry Fuzhou University Fuzhou Institute of.Chemistry National Autonomous University of Mexico Mexico City MX

Density f.nctional theory periodic slab calculations were carded out f.r CO adsorption on a series of.Mo modif.ed Pt（111） surf.ces to provide an insight into the interaction between CO and doped metal surf.ce, an important issue in CO oxidation as well as in promotion and poisoning ef.ects of.catalysis. The modif.cation of.adsorption properties with respect to those of.adsorption on the pure Mo（110） and Pt（111） is described in terms of.changes in the adsorption energies, adsorption sites and vibrational properties occurring upon alloying. We believe that the present Df. calculations can provide important inf.rmation into optimal alloy composition f.r CO-tolerance, which is not easily obtained by experimental methods.

关键词： density f.nctional calculations adsorption molybdenum platinum carbon monoxide bimetallic surf.ces