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141.
Alexandru I. Mitrea 《Calcolo》2018,55(1):10
This paper deals with interpolatory product integration rules based on Jacobi nodes, associated with the Banach space of all s-times continuously differentiable functions, and with a Banach space of absolutely integrable functions, on the interval \([-1,1]\) of the real axis. In order to highlight the topological structure of the set of unbounded divergence for the corresponding product quadrature formulas, a family of continuous linear operators associated with these product integration procedures is pointed out, and the unboundedness of the set of their norms is established, by means of some properties involving the theory of Jacobi polynomials. The main result of the paper is based on some principles of Functional Analysis, and emphasizes the phenomenon of double condensation of singularities with respect to the considered interpolatory product quadrature formulas, by pointing out large subsets (in topological meaning) of the considered Banach spaces, on which the quadrature procedures are unboundedly divergent. 相似文献
142.
Montgomery Van Wart Alexandru Roman XiaoHu Wang Cheol Liu 《Telematics and Informatics》2017,34(5):527-537
Information and communication technologies (ICTs) are having a profound effect in society and organizations. However, the literature on ICT adoption—from selection to implementation—has not been well integrated into leadership theory. This is particularly true in terms of adoption. Leaders must adopt ICTs not only for their own competence—an antecedent condition for what is considered e-leadership, but choose, recommend, and support implementation of ICTs for their organizations/units to use. Leaders are also expected to become effective in dealing and navigating the challenges of leading within the digital space. At this moment, there are two pertinent literatures: the technology adoption literature and the enterprise resource planning literature—which can be considered an important special case of leadership change management literature—and which could provide the theoretical basis for developing a unified theoretical perspective on e-leadership. This article provides a framework and propositions to connect these literatures by focusing on the effects of individual leader characteristics on the ICT adoption process from both a personal and enterprise-wide perspective. Study limitations and future research opportunities are outlined. 相似文献
143.
Hyun-Seog Roh Yong Wang David L. King Alexandru Platon Ya-Huei Chin 《Catalysis Letters》2006,108(1-2):15-19
Supported Rh catalysts have been developed for selective H2 production at low temperatures. Ethanol dehydration is favorable over either acidic or basic supports such as γ-Al2O3 and MgAl2O4, while ethanol dehydrogenation is more favorable over neutral supports. CeO2–ZrO2-supported Rh catalysts were found to be especially effective for hydrogen production. We focused on a support prepared by
a co-precipitation method having composition Ce0.8Zr0.2O2. A 2%Rh/Ce0.8Zr0.2O2 catalyst, prepared via impregnation without pre-calcination of support, exhibited the highest H2 yield at 450 °C among various supported Rh catalysts evaluated in this study. This may be due to both the strong interaction
between Rh and Ce0.8Zr0.2O2 and the high oxygen transfer rate favoring reforming of acetaldehyde instead of methane production. 相似文献
144.
Producing polypropylene (PP) foams with satisfactory cell morphologies in rotational foam molding is feasible. However, the narrow interval between the melting temperature of PP and the onset decomposition temperature of the applicable chemical blowing agent (CBA), and the relatively low melt strength of PP at elevated temperatures are considered the greatest obstacles in processing PP foams. The experimental results revealed that the morphology of the foams obtained by processing PP pellets that have been pre‐compounded with a CBA could be governed by either pellet sintering or cell coalescence. The viscosity of the basic PP resin and the processing temperature determine which of these two key factors will assume a predominating influence towards the foaming process. The desired volume expansion ratio (VER) of the foam also plays an important role since it determines the formulation of the foamable resin and the shot size. Desirable PP foam structures in compounding based rotational foam molding can be obtained only if pellet sintering takes place prior to the decomposition of the CBA and if the processing temperature during the foaming process is kept lower than the temperature of cell coalescence. 相似文献
145.
In this paper we propose an optimized version, at the end-points, of the Akima's interpolation method for experimental data fitting. Comparing with the Akima's procedure, the error estimate, in terms of the modulus of continuity, is improved. Similarly, we optimize at the end points the Catmull–Rom's cubic spline. The properties of the obtained splines are illustrated on a numerical experiment. 相似文献
146.
Maria Elena Zarif Saa Alexandra Yehia Bogdan Bi Veronica Stulu Sorin Vizireanu Gheorghe Dinescu Alina Maria Holban Florica Marinescu Ecaterina Andronescu Alexandru Mihai Grumezescu Alexandra Ctlina Bîrc Alexandru Titus Farcaiu 《International journal of molecular sciences》2021,22(23)
Despite the technological progress of the last decade, dental caries is still the most frequent oral health threat in children and adults alike. Such a condition has multiple triggers and is caused mainly by enamel degradation under the acidic attack of microbial cells, which compose the biofilm of the dental plaque. The biofilm of the dental plaque is a multispecific microbial consortium that periodically develops on mammalian teeth. It can be partially removed through mechanical forces by individual brushing or in specialized oral care facilities. Inhibition of microbial attachment and biofilm formation, as well as methods to strengthen dental enamel to microbial attack, represent the key factors in caries prevention. The purpose of this study was to elaborate a cold plasma-based method in order to modulate microbial attachment and biofilm formation and to improve the retention of fluoride (F−) in an enamel-like hydroxyapatite (HAP) model sample. Our results showed improved F retention in the HAP model, which correlated with an increased antimicrobial and antibiofilm effect. The obtained cold plasma with a dual effect exhibited through biofilm modulation and enamel strengthening through fluoridation is intended for dental application, such as preventing and treating dental caries and enamel deterioration. 相似文献
147.
Adriana Vlasa Simona Varvara Aurel Pop Caius Bulea Liana Maria Muresan 《Journal of Applied Electrochemistry》2010,40(8):1519-1527
The present paper aims to investigate the electrodeposition on steel substrate and the corrosion behavior of Zn–TiO2 nanocomposite coatings. Zn–TiO2 composite coatings were electrodeposited on OL 37 steel from an electrolyte containing ZnCl2, KCl, HBO3 (pH 5.7) brightening agents and dispersed nanosized TiO2. Corrosion measurements were performed in 0.2 g L−1 (NH4)2SO4 solution (pH 3) by using electrochemical methods (open-circuit potential measurements, polarization curves, electrochemical
impedance spectroscopy). The results of electrochemical measurements were corroborated with those obtained by using non-electrochemical
methods (X-ray diffraction, atomic force microscopy and scanning electron microscopy). The results indicate that the composite
coatings exhibit higher corrosion resistance as compared to pure Zn coatings and a non-linear dependence of their polarization
resistance on TiO2 concentration in the plating bath was found. The importance of TiO2 nature and concentration regarding the properties of the composite coatings was demonstrated. 相似文献
148.
Carmen Chifiriuc Valentina Grumezescu Alexandru Mihai Grumezescu Crina Saviuc Veronica Laz?r Ecaterina Andronescu 《Nanoscale research letters》2012,7(1):209
Biofilms formed by fungal organisms are associated with drastically enhanced resistance against most antimicrobial agents, contributing to the persistence of the fungi despite antifungal therapy. The purpose of this study is to combine the unique properties of nanoparticles with the antimicrobial activity of the Rosmarinus officinalis essential oil in order to obtain a nanobiosystem that could be pelliculised on the surface of catheter pieces, in order to obtain an improved resistance to microbial colonization and biofilm development by Candida albicans and C. tropicalis clinical strains. The R. officinalis essential oils were extracted in a Neo-Clevenger type apparatus, and its chemical composition was settled by GC-MS analysis. Functionalized magnetite nanoparticles of up to 20 nm size had been synthesized by precipitation method adapted for microwave conditions, with oleic acid as surfactant. The catheter pieces were coated with suspended core/shell nanoparticles (Fe3O4/oleic acid:CHCl3), by applying a magnetic field on nanofluid, while the CHCl3 diluted essential oil was applied by adsorption in a secondary covering treatment. The fungal adherence ability was investigated in six multiwell plates, in which there have been placed catheters pieces with and without hybrid nanoparticles/essential oil nanobiosystem pellicle, by using culture-based methods and confocal laser scanning microscopy (CLSM). The R. officinalis essential oil coated nanoparticles strongly inhibited the adherence ability and biofilm development of the C. albicans and C. tropicalis tested strains to the catheter surface, as shown by viable cell counts and CLSM examination. Due to the important implications of Candida spp. in human pathogenesis, especially in prosthetic devices related infections and the emergence of antifungal tolerance/resistance, using the new core/shell/coated shell based on essential oil of R. officinalis to inhibit the fungal adherence could be of a great interest for the biomedical field, opening new directions for the design of film-coated surfaces with antibiofilm properties. 相似文献
149.
This paper presents a VHDL-based simulated fault injection (SFI) methodology for quantum circuits. The main objective is to attain a high error modeling capability at a technology independent level. For this purpose, gate level simulation models for quantum circuits have been developed using VHDL. The proposed methodology relies on specific techniques inspired from the simulated fault injection techniques developed for classical CMOS circuits: saboteurs and mutants. In order to perform the simulation campaigns, a library of quantum gates and simulated fault injection components has been developed. The simulation results show that a wide range of quantum faults and error models has been addressed. Furthermore, a comparison between the two SFI techniques is presented. 相似文献
150.
Summary In this paper, the unsteady boundary-layer flow of a micropolar fluid started impulsively from rest near the forward stagnation
point of a two-dimensional plane surface is studied by means of an analytic approach, namely homotopy analysis method. This
approach gives accurate approximations uniformly valid for all dimensionless time. Besides, analytic results are given for
the reduced velocity and microrotation profiles, as well as for the skin friction coefficient when the material parameter
K takes the value K=0 (Newtonian fluid), 1, 3, 5 and 10. To the best of our knowledge, such a kind of series solutions has been never reported. 相似文献