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91.
Safa Raziyeh Soltani Goharrizi Ataallah Jafari Saeed Jahanshahi Javaran Ebrahim 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2497-2514
Journal of Thermal Analysis and Calorimetry - In the present study, double-diffusive mixed convection related to the heat and mass transfer of the solid particles dissolution in a shear flow was... 相似文献
92.
Hyperfine Interactions - Cement clinker is the main component of Portland cement. It is composed of four main phases. One of them is the brownmillerite or the ferrite phase of cement clinker. It is... 相似文献
93.
Mandana Samari Kermani Ned Djilali Saeed Jafari Ebrahim Jahanshahi Javaran 《Journal of Dispersion Science and Technology》2018,39(6):777-791
The dynamics and rheology of particles in a Newtonian fluid subjected to shear are simulated using Lattice Boltzmann Method. A computationally-efficient Smoothed Profile Method is used to resolve fluid-solid interactions, and the Lennard-Jones inter-particle potential is implemented to account for inter-particle forces. The use of a bi-periodic computational domain with Lees-Edward boundary conditions allows simulation for systems consisting of a large number of particles under shear. The method is validated for single and dual particle problems and an analysis is performed for multi-particle problems under a range of shear rates and particle fractions. The introduction of particle-particle interactions, which are physically important in many engineering processes, is found to have a considerable impact on the dynamics, agglomeration and rheology. The total stress exhibits high unsteadiness primarily due to the solid component contribution, at higher particle fractions. The simulations underscore the complex interplay between shear, interparticle forces and agglomeration and the complex dependencies of the rheological properties. 相似文献
94.
Mohyeddin Safarzaei Malek Taher Maghsoodlou Ebrahim Mollashahi Nourallah Hazeri Mojtaba Lashkari 《Research on Chemical Intermediates》2018,44(12):7449-7458
A one-pot three-component condensation reaction of 3-amino-5-methylisoxazole, aryl aldehyde and 2-naphthol to afford the corresponding 3-amino isoxazolmethylnaphthols in good to excellent yields. The remarkable features of this new procedure are high conversions, clean reaction condition, short reaction time, nonhazardous and environmentally friendly reaction condition, inexpensive and easily commercially availability of the catalyst and simple work-up procedures. 相似文献
95.
Saeidian Hamid Sadighian Hamed Arabgari Masomeh Mirjafary Zohreh Ayati Seyed Ebrahim Najafi Ezzatollah Moghaddam Firouz Matloubi 《Research on Chemical Intermediates》2018,44(1):601-612
Research on Chemical Intermediates - We report robust green synthesis of novel 1,2,3-triazole-based sulfonamides bearing different motifs such as fluorine under click conditions in presence of a... 相似文献
96.
Ferhat Can Özkaya Weaam Ebrahim Maximilian Klopotowski Zhen Liu 《Natural product research》2018,32(7):840-843
The anti-neuroinflammatory meroterpenoid citreohybridonol was isolated for the first time from a sponge-derived fungus Penicillium atrovenetum. In this study, in addition to isolation and structure featuring, its unambiguous absolute configuration was determined exclusively by single crystal X-ray diffraction. The C-17-keto tautomer was clearly observed in X-ray analysis. The substance crystallises in the monoclinic space group P21 with a = 10.7496(5) Å, b = 14.3286(7) Å, c = 17.4909(8) Å, β = 103.235(2)°, V = 2622.5(2) Å3, Z = 2, Dcalcd = 1.280 g/cm3. The chirality of the asymmetric carbon atoms was as follows: C3 (S), C5 (R), C6 (S), C8 (S), C9 (R), C10 (R), C13 (R), C14 (R). 相似文献
97.
Shahram Mehdipour-Ataei Samal Babanzadeh Ebrahim Abouzari-Lotf Samaneh Khodami 《Soft Materials》2018,16(4):265-274
A new diamine was prepared via reaction between 8-hydroxy-5-nitroquinoline and 4-nitrobenzoyl chloride, followed by reduction of the nitro groups of the resulted compound. Novel quinoline-based poly(ester-amide)s were produced through polycondensation reactions of the prepared diamine with different diacid chlorides. The monomer and poly(ester-amide)s were characterized and properties of the polymers including solution viscosity, thermal behavior and stability, solubility, and crystallinity were studied.High thermal stability and improved solubility was observed for the polymers, indicating successful designing of monomer and related polymers for overcoming the main issue of thermally stable polymers, i.e. the problem of increasing solubility versus high thermal stability.Also, by changing the diacid chlorides for the preparation of poly(ester-amide)s, the structure-property relations were investigated. 相似文献
98.
The chemical composition of a hydrodistilled oil of Stachys inflata Benth. growing wild in Iran was examined by GC/MS. Thirty-nine constituents were identified. The major components of the oil were germacrene-D (16.9%), bicyclogermacrene (16.6%), -pinene (11.3%), -phellandrene (9.8%), bicycloelemene (6.6%), -pinene (5.6%), and spathulenol (3.2%). 相似文献
99.
Shohreh Nafisi Fatemeh Ghoreyshi Kahangi Ebrahim Azizi Nader Zebarjad Heidar-Ali Tajmir-Riahi 《Journal of Molecular Structure》2007,830(1-3):182-187
Zanamivir (ZAN) is the first of a new generation of influenza virus-specific drugs known as neuraminidase inhibitors, which acts by interfering with life cycles of influenza viruses A and B. It prevents the virus spreading infection to other cells by blocking the neuraminidase enzyme present on the surface of the virus. The aim of this study was to examine the stability and structural features of calf thymus DNA and yeast RNA complexes with zanamivir in aqueous solution, using constant DNA or RNA concentration (12.5 mM) and various zanamivir/polynucleotide (P) ratios of 1/20, 1/10, 1/4, and 1/2. FTIR and UV–visible spectroscopy are used to determine the drug external binding modes, the binding constant and the stability of zanamivir–DNA and RNA complexes in aqueous solution. Structural analysis showed major interaction of zanamivir with G-C (major groove) and A-T (minor groove) base pairs and minor perturbations of the backbone PO2 group with overall binding constants of Kzanamivir–DNA = 1.30 × 104 M−1 and Kzanamivir–RNA = 1.38 × 104 M−1. The drug interaction induces a partial B to A-DNA transition, while RNA remains in A-conformation. 相似文献
100.
A. J. Blotcky F. G. Hamel A. Stranik A. Ebrahim R. B. Sharma E. P. Rack S. S. Solomon 《Journal of Radioanalytical and Nuclear Chemistry》1989,131(2):319-329
A method is described for determination of vanadium in biological tissues. This method consists of a wet digestion of the tissue with nitric acid followed by anion exchange chromatography, neutron irradiation, and radioassay. The chromatographic separation will allow the decontamination of vanadium from radioactivatable sodium and chlorine which are present in large quantities in biological tissues. The validity of the method is evaluated by employing NBS-SRM 157 and 157a Bovine Liver employing the method of standard additions. The method is successfully applied to human, cow and rat liver specimens. The detection limit of the method is one ppb. 相似文献