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111.
It is well known by results of Golod and Shafarevich that the Hilbert 2-class field tower of any real quadratic number field, in which the discriminant is not a sum of two squares and divisible by eight primes, is infinite. The aim of this article is to extend this result to any real abelian 2-extension over the field of rational numbers. So using genus theory, units of biquadratic number fields and norm residue symbol, we prove that for every real abelian 2-extension over ? in which eight primes ramify and one of theses primes ≡ ?1 (mod 4), the Hilbert 2-class field tower is infinite. 相似文献
112.
Azizi Masitah Abdul Halim Isahak Wan Nor Roslam Wan Masdar Mohd Shahbudin Somalu Mahendra Rao Yarmo Mohd Ambar 《Research on Chemical Intermediates》2018,44(11):6787-6802
Research on Chemical Intermediates - Hydrogen is considered a promising energy carrier for the future, especially for clean energy generation via fuel cell technologies. Formic acid is one of the... 相似文献
113.
S. Saber 《Mathematica Slovaca》2013,63(3):521-530
For a q-pseudoconvex domain Ω in ? n , 1 ≤ q ≤ n, with Lipschitz boundary, we solve the $\bar \partial $ -problem with exact support in Ω. Moreover, we solve the $\bar \partial $ -problem with solutions smooth up to the boundary over Ω provided that it has smooth boundary. Applications are given to the solvability of the tangential Cauchy-Riemann equations on the boundary. 相似文献
114.
R. Pourgholi N. Azizi Y.S. Gasimov F. Aliev H.K. Khalafi 《Communications in Nonlinear Science & Numerical Simulation》2009,14(6):2664-2669
In this paper, we consider an inverse heat conduction problem (IHCP). A set of temperature measurements at a single sensor location inside the heat conduction body is required. Using a transformation, the ill-posed IHCP becomes a Cauchy problem. Since the solution of Cauchy problem, exists and is unique but not always stable, the ill-posed problem is closely approximated by a well-posed problem. For this new well-posed problem, the existence, uniqueness, and stability of the solution are proved. 相似文献
115.
Aouissi S. Mayer D. C. Ismaili M. C. Talbi M. Azizi A. 《Periodica Mathematica Hungarica》2020,81(2):250-274
Periodica Mathematica Hungarica - Let $$k=k_0(\root 3 \of {d})$$ be a cubic Kummer extension of $$k_0=\mathbb {Q}(\zeta _3)$$ with $$d>1$$ a cube-free integer and $$\zeta _3$$ a primitive... 相似文献
116.
M. Saber Tehrani M. T. Vardini P. Abroomand Azar S. W. Husain 《Journal of the Iranian Chemical Society》2010,7(3):759-769
A PVC-based membrane containing metoprolol molecularly imprinted polymer (MIP) coated directly on graphite electrode for the determination of metoprolol in real samples is reported. This potentiometric sensor was designed by dispersing the MIP particles in dioctylphthalate plasticizer as solvent mediator and then embedded in polyvinyl chloride matrix. The electrode exhibited a near-Nernstian slope of 55.4 ± 1 mV decade-1 for metoprolol over a wide concentration range between 2.0 × 10-7-8.0 × 10-3 M and a detection limit of 1.3 × 10-7 M. With a response time of about 14 s it could be used for at least 6 months without any divergence in potential. The proposed electrode can be used in the pH range of 3.5-10.5 and can reveal good selectivities for metoprolol over a wide variety of ions. Finally, the designed sensor was successfully applied as an indicator electrode to determine the concentration of metoprolol in tablets, human urine and plasma. The results were compared favorably with those obtained by HPLC method and showed satisfactory agreements with them. 相似文献
117.
The synthesis of zeolite ANA under static hydrothermal conditions was performed accompanied by an additional static and ultrasonic‐assisted aging of the reaction mixture prior to crystallization. The aging process was compared with stirring‐assisted aging, microwave‐assisted aging and syntheses without any aging. The influence of aging time on the crystallization time of zeolite ANA was investigated. The static and ultrasonic‐assisted aging can shorten the crystallization time of the ANA phase. Moreover, ultrasonic‐assisted aging leads to altered morphologies of the particles. The products were characterized by X‐ray diffraction (XRD) and scanning electron microscopy (SEM). 相似文献
118.
M. Taghinejad-Roudbaneh S.R. Ebrahimi S. Azizi P. Shawrang 《Radiation Physics and Chemistry》2010,79(12):1264-1269
The aim of the present study was to determine the impact of electron beam (EB) irradiation at doses of 15, 30 and 45 kGy on the nutritional value of canola meal. The phytic acid and total glucosinolate content of EB-irradiated canola meal decreased as irradiation doses increased (P<0.01). From in situ results, irradiation of canola meal at doses of 45 kGy decreased (P<0.05) the effective degradibility of crude protein (CP) by 14%, compared with an untreated sample. In vitro CP digestibility of EB-irradiated canola meal at doses of 15 and 30 kGy was improved (P<0.05). Electrophoresis results showed that napin and cruciferin sub-units of 30 and 45 kGy EB-irradiated canola meal were more resistant to degradation, compared with an untreated sample. Electron beam irradiation was effective in protecting CP from ruminal degradation and reducing antinutritional factors of irradiated canola meal. 相似文献
119.
Saber Tehrani Mohammad Vardini Mohammad Taghi Abroomand Azar Parviz Husain Syed Waqif 《中国化学》2010,28(4):647-655
A new adsorbent for molecularly imprinted solid phase extraction (MISPE) of metoprolol was synthesized using methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross‐linking agent causing a non‐covalent, bulk, thermal radical‐polymerization. Control polymer (non‐imprinted polymer) was prepared under well defined conditions without the use of metoprolol. The synthesized polymers were characterized by IR spectroscopy, X‐ray diffraction and thermal analysis techniques. This polymer was used for the rapid extraction and preconcentration of metoprolol from real samples prior to spectrophotometric determination. Extraction efficiency and the influence of flow rates of sample and stripping solutions, pH, type of eluent for elution of metoprolol from polymer, break through volume and limit of detection were studied. The detection limit of the proposed method is 0.4 ng·mL?1. The method was applied successfully to the recovery and determination of metoprolol in tablets, human urine and plasma samples. 相似文献
120.
This paper is a reply to a recent paper on the isomers of trisulfur oxides (Chem. Commun., 2005, 3712) where the accuracy of the CASPT2 method is called in question. We illustrate that their results are due to an inadequate choice of active orbitals. Some results for related O and S containing molecules are also presented to strengthen the argumentation. It is concluded that the CASPT2 method is accurate to at least 0.1 eV (2 kcal mol(-1)) for this type of systems. 相似文献