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31.
Research on Chemical Intermediates - The corrosion and scale inhibition efficiency of Mazuj gall extract in simulated cooling water has been evaluated. Potentiodynamic polarization, electrochemical... 相似文献
32.
33.
Sara Taha Gelan Rafat Fatma Aboshosha Fotouh R. Mansour 《Journal of Analytical Chemistry》2017,72(2):239-242
A simple portable spectrophotometer was constructed and used to perform analytical experiments. The developed model uses available tools and materials such as light emitting diode lamps, compact discs, plastic and cardboard boxes and a cell phone camera to build a design that illustrates the major components of spectrophotometers. The spectra of serial concentrations of KMnO4 (50?600 μM) were recorded and the values of absorbance were extracted at λmax to build the calibration curve. A linear relationship between the concentration and absorbance was obtained with the coefficient of determination 0.994. The model was also utilized to study the spectra of KMnO4, phenolphthalein and bromothymol blue in comparison with a Shimadzu UV-1800 spectrophotometer as a reference instrument. In spite of the differences in the observed spectra, the recorded λmax were almost identical to those measured by the developed model. The model was successfully used to determine the concentration of sodium alendronate through ligand-exchange complexation with ferric salicylate. 相似文献
34.
In this study, the organosilane‐functionalized graphene oxide as a stabilizer was prepared by a facile one‐step silylation approach. [Cu(PPh3)3Cl] complex was successfully immobilized onto the graphene oxide surface through coordination interaction with organosilane ligand spacers. The supported catalyst showed enhanced catalytic performance toward Sonogashira reaction of aryl halides with phenylacetylene in water solvent compared with the homogeneous analogues, and it could be readily recycled and reused several times without discernible loss of its activity. 相似文献
35.
Hashemi Karouei Seyed Hossein Ajarostaghi Seyed Soheil Mousavi Gorji-Bandpy Mofid Hosseini Fard Seyed Reza 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1455-1466
Journal of Thermal Analysis and Calorimetry - In the present study, the effect of inserting an innovative curved turbulator and utilizing two types of hybrid nanofluids on thermal performance in a... 相似文献
36.
The Ramanujan Journal - In this paper, we show formally how can we generate continued fractions starting from three-term contiguous relations. Then as examples, starting from certain contiguous... 相似文献
37.
The properties of nuclear matter are studied in the frame of the Brueckner theory. The Brueckner-Hartree-Fock approximation plus two-body density-dependent Skyrme potential which is equivalent to three-body interaction are used. Various modern nucleon-nucleon potentials are used in the framework of the Brueckner-Hartree-Fock approximation, e.g.: CD-Bonn potential, Nijm1 potential, and Reid 93 potential. These modern nucleon-nucleon potentials fit the deuteron properties and are phase shifts equivalent. The equation of state at T = 0, pressure at T = 0, 8, and 12 MeV, free energy at T = 8 and 12 MeV, nuclear matter incompressibility, and the symmetry energy calculation are presented. The hot properties of nuclear matter are calculated using T 2-approximation method at low temperatures. Good agreement is obtained in comparison with previous theoretical estimates and experimental data, especially at low densities. 相似文献
38.
The European Physical Journal C - In this paper the charged Higgs signal through the decay to a pair of muon and neutrino (H ±→μν) is analyzed. The analysis attempts to... 相似文献
39.
Accurate knowledge of bone properties is central in the prediction of failure and the development of injury treatment protocols.
Often when bone properties are measured experimentally, bone specimens have to be chemically preserved prior to or during
testing. Understanding the effect of the bone preservation method on the material properties is important. Degradation of
properties due to preservation methods may lead to incorrect reporting of values of the bone properties. A salient question
is, therefore, whether the preservation of bovine cortical bone in ethanol for extended periods of time affects fracture toughness;
and if so, whether that affect is reversible. To answer these questions, a three-point bending test set-up was constructed
to perform experiments over a period of 9 weeks. A total of 109 specimens of cortical bone of the same orientation were manufactured
from the mid-diaphysis of the femur. These specimens were separated into three groups based on location in the femur; namely,
medial, lateral, and posterior. The specimens were preserved in ethanol. At the end of each week, a sample of specimens was
selected for testing, with the last sample tested after 9 weeks of preservation. It was shown that after 9 weeks of preservation
in ethanol, followed by rehydration with physiological saline, the fracture toughness of the specimen was unchanged from that
of the control specimen. Omission of rehydration in saline resulted in to an increased fracture toughness of up to 17%. 相似文献
40.
Dadkhoda Ghazanfari Mohammed M. Hashemi Mohammad Reza Akhgar Mohammad Mehdi Foroughi Fariba Najafi-Zadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):3018-3022
The ring-opening reaction of epoxides with thiols by SbCl 3 supported on Kieselguhr under solvent-free conditions, afforded high yields of β-hydroxy sulfides. Nucleophilic attack of the thiols occurs regioselectively at the less hindered side of the epoxides. 相似文献