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Plasma density measurement and downstream etching of silicon and silicon oxide in Ar/NF3 mixture remote plasma source

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Plasma science and Technology 2019年第6期21卷 52-57页

作者： h j YEOM D h ChOI Y s LEE j h KIM D j sEONG s j YOU h C LEE Korea Research Institute of standards and science(KRIss) Daejeon 34113 Republic of Korea Department of Physics Chungnam National University Daejeon 34134 Republic of Korea

In this study,plasma density measurements were performed near the plume region of the remote plasma source (RPs) in Ar/NF3 gas mixtures using a microwave cutoff *** measured plasma density is in the range of 1010-1011 cm-3 in the discharge conditions with RPs powers of 2-4 kW and gas pressures of 0.87-4 *** plasma density decreased with increasing gas pressures and RPs powers under various Ar/NF3 mixing *** decrease in the plasma density measured at the fixed measurement position (plume region) can be understood by the reduction of the electron energy relaxation length with increases in the gas pressures and mixing ratio of NF3/(Ar/NF3).We also performed downstream etching of silicon and silicon oxide films in this *** etch rate of the silicon films significantly increases while the silicon oxide is slightly etched with the gas pressures and *** was also found that the etch rate strongly depends on the wafer position on the processing chamber electrode,and that the etch selectivity reached 96-131 in the discharge conditions of RF powers (3730-4180 W) and gas pressures (3.6-4 Torr).

关键词： remote plasma source electron density cutoff probe downstream etch

Computational study on influence of RF shielding box on inductance of coil

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Plasma science and Technology 2019年第6期21卷 23-28页

作者： s j KIM j j LEE Y s LEE j h KIM s j YOU Applied Physics lab for PLasma Engineering(APPLE) Department of Physics Chungnam National University Daejeon 34134 Republic of Korea Korea Research Institute of standards and science(KRIss) Daejeon 34113 Republic of Korea

Despite the fact that a radio frequency (RF) shielding box affects a coil inductance used in matching network,RF engineers have used a coil inductance measured in open space on designing matching networks since it is difficult to precisely measure the coil inductance within the RF shielding *** this work,we investigate the influences of the RF shielding box on the coil inductance via a 3D full electromagnetic wave *** results shows that the coil inductance decreases from-6.0% to-11.9% compared with its ideal inductance depending on coil positions within the RF shielding *** inductive and capacitive coupling between the coil and surfaces of the RF shielding box contribute to the reduction of the coil *** expect that these results would be useful for those who design RF matching networks.

关键词： 3D full EM wave simulation RF matching component RF shield inductive and capacitive coupling

Variational Calculus With Conformable Fractional Derivatives

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IEEE/CAA journal of Automatica sinica 2017年第2期4卷 340-352页

作者： Matheus j.Lazo Delfim F.M.torres Instituto de Matemática Estatística e Física-FURG Center for Research and Development in Mathematics and Applications (CIDMA) Department of MathematicsUniversity of Aveiro

Invariant conditions for conformable fractional problems of the calculus of variations under the presence of external forces in the dynamics are studied. Depending on the type of transformations considered, different necessary conditions of invariance are obtained. As particular cases, we prove fractional versions of Noether's symmetry theorem. Invariant conditions for fractional optimal control problems, using the hamiltonian formalism, are also investigated. As an example of potential application in Physics, we show that with conformable derivatives it is possible to formulate an Action Principle for particles under frictional forces that is far simpler than the one obtained with classical fractional derivatives.

关键词： Conformable fractional derivative fractional calculus of variations fractional optimal control invariant variational conditions Noether’s theorem

Effect of pesticides on phosphorylation of tau protein,and its influence on Alzheimer’s disease

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World journal of Clinical Cases 2023年第24期11卷 5628-5642页

作者： Erandis D torres-sánchez Genaro G Ortiz Emmanuel Reyes-Uribe juan h torres-jasso joel salazar-Flores Department of Medical and Life sciences University Center of la CienegaUniversity of GuadalajaraOcotlan 47820JaliscoMexico Department of Philosophical and Methodological Disciplines and service of Molecular Biology in Medicine hospital Civil University of GuadalajaraGuadalajara 44340JaliscoMexico Department of Biological sciences CUCOSTAUniversity of GuadalajaraPuerto Vallarta 48280JaliscoMexico

Alzheimer’s disease(AD)is a progressive and neurodegenerative illness which results in alterations in cognitive *** is characterized by loss/dysfunction of cholinergic neurons,and formation of amyloid plaques,and formation of neurofibrillary tangles,among other changes,due to hyperphosphorylation of *** to pesticides in humans occurs frequently due to contact with contaminated food,water,or ***,organophosphates,carbamates,pyrethroids and neonicotinoids are associated with the most diagnosed incidents of severe cognitive *** aim of this study was to determine the effects of these pesticides on the phosphorylation of tau protein,and its cognitive implications in the development of *** was found that exposure to pesticides increased the phosphorylation of tau protein at sites ser198,ser199,ser202,Thr205,ser396 and *** with these chemicals altered the enzymatic activities of cyclin-dependent kinase 5 and glycogen synthase kinase 3 beta,and protein ***,it altered the expression of the microtubule associated protein tau gene,and changed levels of intracellular *** changes affected tau protein phosphorylation and neuroinflammation,and also increased oxidative *** addition,the exposed subjects had poor level of performance in tests that involved evaluation of novelty,as test on verbal,non-verbal,spatial memory,attention,and problem-solving skills.

关键词： Organochlorines Organophosphates Carbamates Pyrethroids Neonicotinoids Tau protein

Potential risk genes for primary sjogren's syndrome from a meta-analysis by linear regression and random forest classification

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Genes & Diseases 2024年第3期11卷 128-131页

作者： Tomas Cerdo Teresa torres Moral Maimonides Biomedical Research Institute of Cordoba(IMIBIC) Reina Sofia University HospitalUniversity of CordobaCordoba 14004Spain Centre for Rheumatology Research Division of MedicineUniversity College LondonLondon W1T 4JFUK Faculty of Computer sciences Multimedia and TelecommunicationUniversitat Oberta de CatalunyaBarcelona 08018Spain Dermatology Department Melanoma UnitAugust Pi i Sunyer Biomedical Research Institute(IDIBAPS)and Hospital ClinicBarcelona 08036Spain Center for Networked Biomedical Research on Rare Diseases(CIBERER) Carlos II Health InstituteMadrid 28029Spain

Primary sjogren's syndrome(pss)is one of the most widespread autoimmune diseases with unknown origin,characterized by a lymphocytic infiltrate of the exocrine glands and the production of anti-ssA/Ro and anti-ssB/La antibodies that cause dysfunction and destruction mainly of salivary and lachrymal glands,leading to dry eyes and dry *** the absence of a standardized evidence-based screening tool to decide which patients with dry eye must be referred for study of this pathology.

关键词： sjogren lymphocytic salivary

RANs simulations of the U and V grooves effect in the subcritical flow over four rotated circular cylinders

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journal of hydrodynamics 2015年第4期27卷 569-578页

作者： ALONZO-GARCIA A. GUTIERREZ-torres C.del C. jIMENEZ BERNAL j.A. MOLLINEDO-PONCE de LEON h.R. MARTINEZ-DELGADILLO s.A. BARBOsA-sALDANA j.G. Instituto Politécnico Nacional SEPI ESIME ZacatencoLABINTHAP U.P.Adolfo López Mateos Edif.5 3er.PisoMéxicoD.F.México Instituto Politécnico Nacional UPIITAAv.IPN 2580C.P.07340MéxicoD.F.México Universidad Autónoma Metropolitana-Azcapotzalco Depto.Ciencias BásicasAv.San Pablo 180Azcapotzalco C.P 07740MéxicoD.F.México

This paper presents a CFD study about the effect of the V and U grooves in the flow over four cylinders in diamond shape configuration at subcritical flow conditions（Re= 41 000）. The k- ε Realizable turbulence model was implemented to fully structured hexahedral grids with near-wall refinements. Results showed that the numerical model was able to reproduce the impinging flow pattern and the repulsive forces present in the lateral cylinders of the smooth cylinder array. As a consequence of the flow alignment induced by the grooves, a jet-flow is formed between the lateral cylinders, which could cause an important vortex induced vibration effect especially in the rear cylinder. The magnitudes of the shear stresses at the valleys and peaks for the V grooved cylinders were lower than those of the U grooved cylinders, but the separation points were delayed due the U grooves presence. It is discussed the presence of a blowing effect caused by counter-rotating eddies located near the grooves peaks that cause a decrease of the shear stresses in the valleys, and promote them at the peaks.

关键词： RANs model grooved cylinder four cylinders subcritical flow impinging flow

Numerical analysis of thermal plasma scrubber for CF4 decomposition

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Plasma science and Technology 2019年第6期21卷 9-14页

作者： j KO T h KIM s ChOI Department of Nuclear and Energy Engineering Jeju National University Jeju 63243 Republic of Korea Institute for Nuclear science and Technology Jeju National University Jeju 63243 Republic of Korea

CF4 gas emitted in the semiconductor and display manufacturing process is a very harmful greenhouse *** must be removed or converted safely due to its extreme *** a CF4 decomposition system using a thermal plasma scrubber was commercialized,its removal efficiency is *** this work,a numerical analysis of CF4 decomposition in the thermal plasma scrubber was carried out in order to propose an efficient decomposition *** decomposition and recombination temperatures of CF4 were analyzed using thermodynamic equilibrium *** chemical reaction of CF4 decomposition into carbon and fluorine gas was considered in this numerical *** injection position and angle of the CF4 were controlled in order to enhance the decomposition *** vertical injection of CF4 near the torch exit improved the mixing of the CF4 with the thermal plasma *** addition,it was confirmed that the high temperature region expanded due to a vortex generated by strong turbulence in the bottleneck-shaped *** a result,it is revealed that the CF4 injection location and the reactor configuration are the most important factors in improving the decomposition rate.

关键词： numerical simulation decomposition CF4 thermal plasma scrubber

solution of shallow-water equations using least-squares finite-element method

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Acta Mechanica sinica 2008年第5期24卷 523-532页

作者： s.j. Liang j,-h, Tang M.-s. Wu Department of Marine Environmental Informatics National Taiwan Ocean UniversityKeelung 20224 Taiwan China Department of Bioenvironmental Engineering Chung-Yuan Christian University Chung-Li 32023 Taiwan China Department of Geographic Information systems Feng Chia University Taichung 40724 Taiwan China

A least-squares finite-element method （LsFEM） for the non-conservative shallow-water equations is presented. The model is capable of handling complex topography, steady and unsteady flows, subcritical and supercritical flows, and flows with smooth and sharp gradient changes. Advantages of the model include：（1） sources terms, such as the bottom slope, surface stresses and bed frictions, can be treated easily without any special treatment; （2） upwind scheme is no needed; （3） a single approximating space can be used for all variables, and its choice of approximating space is not subject to the Ladyzhenskaya-Babuska-Brezzi （LBB） condition; and （4） the resulting system of equations is symmetric and positive-definite （sPD） which can be solved efficiently with the preconditioned conjugate gradient method. The model is verified with flow over a bump, tide induced flow, and dam-break. Computed results are compared with analytic solutions or other numerical results, and show the model is conservative and accurate. The model is then used to simulate flow past a circular cylinder. Important flow charac-teristics, such as variation of water surface around the cylinder and vortex shedding behind the cylinder are investigated. Computed results compare well with experiment data and other numerical results.

关键词： Least-square finite-element method,shallow-water equations Dam-break Vortex shedding

hydrogen production by catalytic decomposition of methane using a Fe-based catalyst in a fluidized bed reactor

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journal of Natural Gas Chemistry 2012年第4期21卷 367-373页

作者： D.torres s.deLlobet j.L.Pinilla M.j.Lzaro I.suelves R.Moliner Instituto de Carboquímica CSICMiguel Luesma Castn 450018 ZaragozaSpain

Catalytic decomposition of methane using a Fe-based catalyst for hydrogen production has been studied in this work. A Fe/Al2O3 catalyst previously developed by our research group has been tested in a fluidized bed reactor （FBR）. A parametric study ot the effects of some process variables, including reaction temperature and space velocity, is undertaken. The operating conditions strongly affect the catalyst performance. Methane conversion was increased by increasing the temperature and lowering the space velocity. Using temperatures between 700 and 900℃ and space velocities between 3 and 6 LN/（gcat·h）, a methane conversion in the range of 25%-40% for the gas exiting the reactor could be obtained during a 6 h run. In addition, carbon was deposited in the form of nanofilaments （chain like nanofibers and multiwall nanotubes） with similar properties to those obtained in a fixed bed reactor.

关键词： hydrogen production fluidized bed reactor metal catalysts