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11.
Valiollah Mirkhani Shahram Tangestaninejad Majid Moghadam Bahram Yadollahi Ladan Alipanah 《Monatshefte für Chemie / Chemical Monthly》2004,135(10):1257-1263
Summary. Efficient esterification of primary and sterically-hindered secondary or tertiary alcohols with acetic anhydride was achieved in the presence of ammonium decatungestocerate(IV) icosahydrate, (NH4)8[CeW10O36]·20H2O, as catalyst in high yields. Primary and secondary alcohols were also converted to their corresponding acetates and formates with acetic acid and ethyl formate in the presence of this catalyst. Easy work-up, non-toxicity, reusability, and stability of the catalyst are noteworthy advantages of this method. 相似文献
12.
Ladan Arissian 《Optics Communications》2006,264(1):169-173
Spectroscopy of a Λ structure in 87Rb is performed with a mode locked laser. A dark line, resulting from population trapping between the hyperfine levels, is observed when the repetition rate is 1/57th of the hyperfine splitting. Simulation of coherent interaction of Rb atoms with laser pulses shows darklines corresponding to different submultiple of the hyperfine splitting. It is demonstrated experimentally and theoretically that the resonance width is insensitive to fluctuations in optical frequency. 相似文献
13.
Ladan Edjlali 《中国化学会会志》2008,55(6):1322-1325
The compounds with isoxazole moiety have many pharmacological, biological and industrial applications, specifically their antiviral activity. In this research work, seven new compounds of 3,5‐disubstituted isoxazoles were synthesized. Propargyl alcohol ( 1 ) reacted with benzoyl chloride to give propargylphenylcarboxylate ( 2 ). Then, the aldehydes ( 3a‐3g ) were converted to the related oximes ( 4a‐4g ) and nitrileoxides in situ by NaOCl, consequently. Reaction of compound 2 with nitrileoxides in a [3+2] cycloaddition reaction gave regiospecifically isoxazoles ( 5a‐5g ). 1H NMR, 13C NMR, FT‐IR, and elemental analyses confirmed the structure of the synthesized compounds. 相似文献
14.
The novel diastereomeric sulfonylamide derivatives 4a–h were synthesized by multi-component reactions between (l)-α-amino acids, 1, aromatic aldehydes, 2 and p-toluenesulfonylmethyl isocyanide, 3 in water/methanol using nanosilica as a catalyst. The one-pot green reactions were carried out at room temperature with a quantitative yield in water/methanol. The yield of the reactions and products was determined and discussed. The reusablity of the catalyst is discussed. 相似文献
15.
Maryam Bayat Meisam Zargar Tamara Astarkhanova Elena Pakina Sergey Ladan Marina Lyashko Sergey I. Shkurkin 《Molecules (Basel, Switzerland)》2021,26(10)
In this investigation, for the first time, we used Fragaria ananassa (strawberry) leaf extract as a source of natural reducing, capping or stabilizing agents to develop an eco-friendly, cost-effective and safe process for the biosynthesis of metal-based nanoparticles including silver, copper, iron, zinc and magnesium oxide. Calcinated and non-calcinated zinc oxide nanoparticles also synthesized during a method different from our previous study. To confirm the successful formation of nanoparticles, different characterization techniques applied. UV-Vis spectroscopy, X-ray Diffraction (XRD) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM) coupled with Energy Dispersive X-ray Spectroscopy (EDS), Photon Cross-Correlation Spectroscopy (PCCS) and Fourier Transformed Infrared Spectroscopy (FT-IR) were used to study the unique structure and properties of biosynthesized nanoparticles. The results show the successful formation of metal-based particles in the range of nanometer, confirmed by different characterization techniques. Finally, the presented approach has been demonstrated to be effective in the biosynthesis of metal and metal oxide nanoparticles. 相似文献
16.
Esmail Vessally Ladan Edjlali Maryam Saber Soma Aryana 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(5):791-797
Geometrical structures, Hammett constants, 1H and 13C chemical shift values, molecular electrostatic potential maps, and several thermodynamic parameters of α-acyloxy carboxamide
derivatives (4a–o) were calculated using HF and DFT/B3LYP methods with 6-31G(d) basis set. The optimized structures were compared with analogous compound. The 1H and 13C NMR shielding tensors were computed with the Gauge-Independent Atomic Orbital (GIAO) method. Comparison of the experimental
1H and 13C NMR chemical shifts of 4a–o molecules with the theoretical data indicates good agreement. 相似文献
17.
Fabry-Perot etalons have been fabricated with 3D colloidal photonic crystal mirrors. The colloid films were optimized for high reflection and low loss to provide good finesse values in the 1200-1700 nm spectral range. A cavity quality factor of 2400 and a finesse of 8 together with sharp 0.5 nm wide resonance transmission peaks are reported that attest to the relatively good optical quality of the three-dimensionally structured films and the promise of self-assembly colloidal crystal chemistry in providing novel microporous optical interferometers for potential applications such as environmental and biological sensing. 相似文献
18.
Vegetable oils have been utilized for centuries in the food, cosmetic, and pharmaceutical industries, and they contribute beneficially to overall human health, to active skincare, and to effective treatments. Monitoring of the vegetable oils is carried out by the methods described in the European Pharmacopeia, which is time-consuming, has poor repeatability, and involves the use of toxic organic chemicals and expensive laboratory equipment. Many successful studies using IR spectroscopy have been carried out for the detection of geographical origin and adulteration as well as quantification of oxidation parameters. The aim of our research was to explore FT-IR spectroscopy for assessing the quality parameters and fatty acid composition of cranberry, elderberry, borage, blackcurrant, raspberry, black mustard, walnut, sea buckthorn, evening primrose, rosehip, chia, perilla, black cumin, sacha inchi, kiwi, hemp, and linseed oil. Very good models were obtained for the α-linolenic acid and linoleic acid contents, with R2 = 1.00; Rv2 values of 0.98, 0.92, 0.89, and 0.84 were obtained for iodine value prediction, stearic acid content, palmitic acid content, and unsaponifiable matter content, respectively. However, we were not able to obtain good models for all parameters, and the use of the same process for variable selection was found to be not suitable for all cases. 相似文献
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20.
Majid M. Heravi Ladan Sangsefidi Hossein A. Oskooie Mitra Ghassemzadeh Koroush Tabar-Hydar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):707-709
Adsorbed on silica gel. Dess-Martin periodinane can rapidly oxidize alcohols to the corresponding carbonyl compounds upon exposure to microwave under solvent-free condition. 相似文献