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151.
Nader Noroozi Pesyan Alireza Shokr Mohammad Behroozi Ertan Şahin 《Journal of the Iranian Chemical Society》2013,10(3):565-575
Reaction of 5,5-dimethylcyclohexane-1,3-dione (dimedone), aldehydes and cyanogen bromide in the presence of triethylamine leads to the selective formation of spiro dihydrofurans in moderate to good yields at room temperature. 相似文献
152.
Ali Keivanloo Mohammad Bakherad Sayed Ali Naghi Taheri Shahrzad Samangooei 《Comptes Rendus Chimie》2013,16(3):239-243
An efficient one-pot cross-coupling/1,3-dipolar cycloaddition sequence was developed for a convenient synthesis of 4,5-disubstituted-1,2,3-(NH)-triazoles, starting from various acid chlorides, terminal alkynes and sodium azide in the presence of silica supported-zinc bromide under aerobic conditions. 相似文献
153.
Mohammad Khorrami Ahmad Shariati Amir Aghamohammadi Amir H. Fatollahi 《Physics letters. A》2012,376(5):687-691
It is shown that as far as the linear diffusion equation meets both time- and space-translational invariance, the time dependence of a moment of degree α is a polynomial of degree at most equal to α, while all connected moments are at most linear functions of time. As a special case, the variance is an at most linear function of time. 相似文献
154.
A voltammetric sensor for determination of paracetamol in the presence of morphine is described for the first time. The synthesized CdO nanoparticles were characterized with different methods such as scanning electron microscopy (SEM) and X‐ray diffraction (XRD). The paracetamol and morphine peaks are separated ca. 0.37 and 0.65 V, respectively; hence paracetamol can be analysed in the presence of morphine and more than 21 times of the current excess of paracetamol. The detection limits for paracetamol and morphine were 0.07 and 0.1 μM, respectively. The sensor has been successfully applied for the assay of the above compounds in real samples. 相似文献
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Neeraj Pant N. Pradhan Mohammad Hassan Murad 《International Journal of Theoretical Physics》2014,53(11):3958-3969
We present a spherically symmetric solution of the general relativistic field equations in isotropic coordinates for perfect charged fluid, compatible with a super dense star modeling. The solution is well behaved for all the values of Schwarzschild parameter u lying in the range 0 < u < 0.1727 for the maximum value of charge parameter K = 0.08163. The maximum mass of the fluid distribution is calculated by using stellar surface density as ρ b = 4.6888×1014g cm?3. Corresponding to K = 0.08 and u max = 0.1732, the resulting well behaved solution has a maximum mass M = 0.9324M ⊙ and radius R = 8.00 and by assuming ρ b = 2×1014g cm?3 the solution results a stellar configuration with maximum mass M = 1.43M ⊙ and radius R b = 12.25 km. The maximum mass is found increasing with increasing K up to 0.08. The well behaved class of relativistic stellar models obtained in this work might has astrophysical significance in the study of internal structure of compact star such as neutron star or self-bound strange quark star like Her X-1. 相似文献
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Taher Niknam Mohammad Hassan Khooban Abdollah Kavousifard Mohammad Reza Soltanpour 《Nonlinear dynamics》2014,75(1-2):73-83
This study deals with the problem of controlling a class of uncertain nonlinear systems in the presence of external disturbances. To achieve this goal, a new Optimal Type-2 Fuzzy Sliding Mode Controller (OT2FSMC) is introduced. In the proposed controller, a novel heuristic algorithm, namely particle swarm optimization with random inertia weight (RNW–PSO), is employed. To achieve an optimal performance, the parameters of the proposed controller as well as the input and output membership functions are optimized simultaneously by RNW–PSO. The globally asymptotic stability of the closed-loop system is mathematically proved. Finally, this method of control is applied to the inverted pendulum system as a case study. Simulation results show the system performance is desirable. 相似文献
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