• Synthesis of several aromatic aldazinesSynthesis of several aromatic aldazines

    Abstract. Ten aromatic aldazines: 4-nitrobenzal-, 3-nitrobenzal-, 2-nitrobenzal-, 4-dimethylaminobenzal-, 4-methoxybenzal-, 3-methoxybenzal-, 4-fluorobenzal-, 4-chlorobenzal-, 4-bromobenzaldazine and 7-carboxymethoxy-6-hydroxy-3-sulfoquinolin-5-carbaldazine, were synthesized by condensing two equivalents of an appropriate aldehyde with one equi...

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  • The influence of some environmental factors on the basic anthropometric indexes of students in hanoi secondary schoolsThe influence of some environmental factors on the basic anthropometric indexes of students in hanoi secondary schools

    Abstract. Study was carried out involving 1200 students (600 male and 600 female) aged 12 to 15. They were enrolled in 3 suburban Hanoi schools and 3 urban Hanoi schools. The results show that in general, the basic anthropometric indexes of suburban Hanoi students are not higher than those of urban Hanoi students. For reasons that effect to ant...

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  • Optimising in vitro culture and Agrobacterium tumefaciens-mediated transformation protocols of tobacco BY-2 cellsOptimising in vitro culture and Agrobacterium tumefaciens-mediated transformation protocols of tobacco BY-2 cells

    Abstract. In order to set up a system for production of recombinant proteins using suspension cell culture of Nicotiana tabacum cv. Bright Yellow 2 (BY-2), in vitro culture and genetic transformation protocols of such cells were optimised at the laboratory of Plant Cell Biotechnology, Institute of Biotechnology. Our experiments indicated that t...

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  • Effect of CaCl2 and NaCl additions on concrete corrosivityEffect of CaCl2 and NaCl additions on concrete corrosivity

    Abstract In addition to breaking down the passive film on embedded steel, the level of chloride content in concrete also influences the electrical resistivity of the concrete and, hence, the kinetics of the reinforcement corrosion, as long as the corrosion process is under resistance control. While there is general agreement in the literature th...

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  • Global exponential stability of switched neutral systems with time-varying delaysGlobal exponential stability of switched neutral systems with time-varying delays

    Abstract. This paper deals with the problem of global exponential stability for a class of switched neutral systems with time-varying delays. Based on improved Lyapunov-Krasovskii functional method combined with the Leibniz-Newton formula, linear matrix inequalities (LMIs) conditions are proposed for the exponential stability of the considered ...

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  • The neumann problem for second order hyperbolic equations in nonsmooth domainsThe neumann problem for second order hyperbolic equations in nonsmooth domains

    Abstract. In this paper, we study the Neumann problem for second order hyperbolic equations without initial data in nonsmooth domains. Our intension was to prove the existence of a generalized solution to this problem by applying the results of this problem to the initial data.

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  • In situ Raman and UV–vis spectroscopic studies of polypyrrole and poly(pyrrole-2,6-dimethyl--cyclodextrin)In situ Raman and UV–vis spectroscopic studies of polypyrrole and poly(pyrrole-2,6-dimethyl--cyclodextrin)

    Polypyrrole (PPy) and poly(pyrrole-2,6-dimethyl--cyclodextrin) [P(Py--DMCD)] films prepared by potential cycling in aqueous acidic solutions on indium tin oxide (ITO)-coated glass and gold electrodes were studied by in situ UV–vis and Raman spectroscopy. Characteristic UV–vis and Raman bands were identified and their dependencies on the electrod...

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  • Theoretical investigation of the interaction between monohalogenated ethenes and hydrogen peroxideTheoretical investigation of the interaction between monohalogenated ethenes and hydrogen peroxide

    The complexes between monohalogenated ethenes CH2@CHX (X = F, Cl, Br) and hydrogen peroxide (HP) have been studied theoretically at the MP2/6-311++G(3df,2p) level. The calculations include the optimization of the geometries, the vibrational frequencies and IR intensities of the m(OH) and m(CH) vibrations along with a natural bond orbital (NBO) an...

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  • Genetic algorithms and application in examination schedulingGenetic algorithms and application in examination scheduling

    Abstract. Examination Scheduling is an optimization problem with constraints, a scheduling problem is one of the NP-hard problems, there is no algorithm that can solve them in polynomial time. Genetic algorithm is an algorithm for finding approximate optimal test of the global optimization problems. Application of genetic algorithms on the speci...

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  • Study on band gap energy of pure and Tb3+ doped Zno powderStudy on band gap energy of pure and Tb3+ doped Zno powder

    Abstract. In this paper, we present one method to determine the band gap energy of ZnO and ZnO:Tb3+materials. ZnO:Tb3+ material has prepared by forced hydrolysis method. All samples have zinc oxide hexagonal wurzite structure. The obtained results show that the energy of the band gap depends on Tb3+ molar ratio.

    pdf6 trang | Chia sẻ: thanhle95 | Ngày: 07/07/2021 | Lượt xem: 332 | Lượt tải: 0