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The mechanism of bursting phenomena in Belousov-Zhabotinsky(BZ) chemical reaction with multiple time scales

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science China(Technological sciences) 2010年第3期53卷 748-760页

作者： BI QinSheng faculty of science,Jiangsu University,Zhenjiang 212013,China 1. faculty of science Jiangsu University Zhenjiang 212013 China

The dynamics of a typical Belousov-Zhabotinsky(BZ)reaction with multiple time scales is investigated in this *** forms of periodic bursting phenomena,and specially,three types of chaotic bursters with different structures can be obtained,which are in common with the behaviors observed in *** bifurcations connecting the quiescent state and the repetitive spikes are presented to account for the occurrence of the NKoscillations as well as the different forms of chaotic *** mechanism of the period-adding bifurcation sequences is explored to reveal why the length of the periods in the sequences does not change continuously with the continuous variation of the parameters.

关键词： Belousov-Zhabotinsky(BZ)reaction multiple time scales bursting phenomenon bifurcation mechanism

Analysis of acoustic radiation mode in time domain

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science China(Technological sciences) 2009年第8期52卷 2384-2390页

作者： WU WeiGuo faculty of science, Jiangsu University, Zhenjiang 212013, China 1. faculty of science Jiangsu University Zhenjiang 212013 China

The acoustic radiation mode of plane, whose radiating operator is constructed by Rayleigh integral, is investigated in the time domain and its physical meaning is given. The relationship between the acoustic radiation modes of time domain and frequency domain is discussed. It is verified that the acoustic radiation modes are the natural property of the radiator and they can be obtained by different methods. These time domain radiation modes, whose shapes are only dependent on the geometry size and shape of the radiator, can radiate sound power independently. Especially, the first time domain radiation mode accounts for most of the sound radiation. All these simplify the calculation and control of the structure-borne sound power. Based on these observations, the sound power radiated from the vibrating plate is estimated by the time domain radiation mode for verifying the proposed method. The influence factors on the estimating accuracy in different conditions are discussed.

关键词： acoustic radiation time-domain radiation mode sound power

Surfactants as Inhibitors for Alkaline Corrosion of Aluminium

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Journal of Materials science & Technology 1999年第1期15卷 39-42页

作者： Mervett El Batouti(Department of Chemistry, faculty of science, Alexandria University, Egypt) Department of Chemistry Faculty of Science Alexandria University Egypt

Inhibition of aluminium corrosion in NaOH solution by anionic surfactant as sodium (lauryl)sulphate, cationic surfactant as cetyl trimethyl ammonium bromide and non ionic surfactant asTriton-X 100 has been studied using weight-loss and hydrogen evolution methods. It is foundthat the inhibition efficiency depends on the type of SAS as well as its concentration. The orderof increasing inhibition is as followsSLS < Triton - X 100 < CTABThermodynamic parameters are calculated.

关键词： Figure Surfactants as Inhibitors for Alkaline Corrosion of Aluminium

Some Physical Properties of CuTlSe Alloy

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Journal of Materials science & Technology 2001年第2期17卷 229-232页

作者： A.Abdel All Physics Department, faculty of science , Helwan University, Cairo, Egypt K.A.Sharaf Physics Department, faculty of science, Al-Azhar University for Girls, Cairo, Egypt A.Elshafie Physics Department, faculty of science, Menoufia University, She Helwan Univ Fac Sci Dept Phys Cairo Egypt Al Azhar Univ Girls Dept Phys Fac Sci Cairo Egypt Menoufia Univ Fac Sci Dept Phys Shibin Al Kawm Egypt

The structure and optical properties of Cu0.1Tl2Se3 alloy was studied. X-ray analysis showed that the polycrystalline powder consists of a mixture of two phases Cu3jTlSe2 (monoclinic) and TISe (tetragonal). Chalcopyrite phase CuTISe2 can be obtained by annealing the powder at 250'C for 1 h. Thin film with a monoclinic phase of Cu3TlSe2 was obtained for the thick film (0.7 um). The optical parameters a, n, k, e' and e' and the energy gap were calculated. The thermoelectric power measurements showed that S has a positive polarity over the whole range of temperature.

关键词： Cu Some Physical Properties of CuTlSe Alloy

Some Dielectric Properties of Some Resin Varnishes

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Journal of Materials science & Technology 1995年第2期11卷 119-121页

作者： S.A.El-Henawii(faculty of science, Helwan University, Cairo, Egypt) Heiwan Univ Cairo Egypt

The dielectric constant, the dielectric loss and the power factor of three types of resins namely polyesteramide, alkyd polyesteramide and alkyd resins were measured with in the frequency range of 105 to 107 Hz and the temperature range of 20 to 50℃. The activation energy of dielectric relaxation and the entropy changes were also calculated using the usual rate equation. The results obtained are recorded and discussed.

关键词： Some Dielectric Properties of Some Resin Varnishes RT

Phase behavior of TXs/toluene/water microemulsion systems for solubilization absorption of toluene

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Journal of Environmental sciences 2010年第2期22卷 271-276页

作者： Lian Liu,Senlin Tian ,Ping Ning faculty of Environmental science and Engineering,Kunming University of science and Technology,Kunming 650093,China [a] faculty of Environmental science Engineering Kunming University of Science Technology Kunming 650093 China

Triton Xs （TXs） surfactants/cosurfactant/water/oil （toluene） microemulsion systems for enhancing toluene solubilization were proposed and its potential was investigated for toluene removal from gas stream. The results indicated that TX-100 was superior to other TXs surfactants in removing toluene without cosurfactant. The efficiency of cosurfactants for improving toluene solubilization capacity follows the order： amine 〉 alcohol 〉 acid. According to the factor analysis, the linear cosurfactants are better than the branched ones. The effects of hydrophile-lipophile balance （HLB）, salt （NaCl） concentration and temperature on the formation of microemulsion system were also discussed. The results suggested that the optimum value of HLB was 15, the effect of NaCl concentration on the system was inconspicuous and the lower temperature enhanced the solubilization capacity. Nonionic surfactant-based microemulsions had a significant absorption enhancement for toluene, indicated by as much as 82.72% of toluene in phase composition diagram, which will have a great prospect in air pollution treatment.

关键词： microemulsion phase behavior absorption toluene

AC Conductivity of (As_2Te_3)_(100-x)Ge_x Bulk Glassy System

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Journal of Materials science & Technology 1998年第3期14卷 247-250页

作者： A-Abdel-All(Physics Dept., faculty of science, Helwan University, Cairo, Egypt) Physics Dept. Faculty of Science Helwan University Cairo Egypt

The ac conductivity of the bulk amorphous chalcogenide system (As2Te3)100-xGex (where x=0,5,10,15 and 25 at. pct) was investigated at variable frequencies ranging from 50 Hz to 100 kHz and at different temperatures ranging from 3O to 160℃. lt was found that at a fixed temperature, where n <1 and decreases with temperature. The complex impedence Z was measured over the same frequency and temperature ranges. All samples give a semicircle arc originating at the origin point. This indicates that each composition can be described only by one resistance R and one capacity C, both parallelly combined. The centre below the real axis indicates the relaxation behaviour of the system. The activation energies for conduction were calculated.

关键词： Ge Te AC Conductivity of x)Ge_x Bulk Glassy System As2Te3

Electrical Investigation of Some Silver Containing Ceramics Obtained from Coprecipitated Oxalates

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Journal of Materials science & Technology 1999年第1期15卷 87-90页

作者： M.I.El-Hofy(Physics Department, faculty of science, Menoufia University, Shebin El-Kom, Egypt)A.M.Donia(Chemistry Department, faculty of science, Menoufia University, Shebin El-Kom, Egypt)M.M.Abou-Sekkina(Chemistry Department, faculty of science, Taota Un Physics Department Faculty of Science Menoufia University Shebin El-Kom Egypt Chemistry Department Faculty of Science Menoufia University Shebin El-Kom Egypt Chemistry Department Faculty of Science Tanta University Tanta Egypt

Silver-ceramics (Ag2MO2)(M=Co, Ni, or Cu) were prepared through thermal decompositionof coprecipitated oxalates. Pellets of these materials were annealed at 350℃ for different timeperiods up to 5 h. The effect of ann... 详细信息

关键词： CuO Figure Electrical Investigation of Some Silver Containing Ceramics Obtained from Coprecipitated Oxalates

Effect of Some Admixtures on the Hydration of Silica Fume and Hydrated Lime

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Journal of Materials science & Technology 2000年第4期16卷 375-378页

作者： Eisa E.Hekal (faculty of science, Ain-Shams University, Abbassia 11566, Cairo, Egypt) faculty of science Ain-Shams University Abbassia 11566 Cairo Egypt

The effects of sodium salt of naphthalene formaldehyde sulfonic acid and stearic acid on the hydration of silica fume and Ca(OH)2 have been investigated. The hydration was carried out at 60℃ and W/S ratio of 4 for various time intervals namely, 1, 3, 7 and 28 days and in the presence of 0, 2% and 5% superplasticizer and stearic acid. The results of the hydration kinetics show that both admixtures accelerate the hydration reaction of silica fume and calcium hydroxide during the first 7 days. Whereas, after 28 days hydration there is no significant effect. Generally, most of free calcium hydroxide seems to be consumed after 28 days. In addition, the phase composition as well as the microstructure of the formed hydrates was examined by using X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) respectively.

关键词： rate high Effect of Some Admixtures on the Hydration of Silica Fume and Hydrated Lime acid CSH