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71.
72.
Diego Lomonaco Fabricio Y. Cangane Selma E. Mazzetto 《Journal of Thermal Analysis and Calorimetry》2011,104(3):1177-1183
In this work, poly(methyl methacrylate) films 1% additivated with new thiophosphate esters antioxidants derived from technical
Cashew Nutshell Liquid (CNSL), a byproduct of the cashew nut (Anacardium occidentale L.) industry, were investigated by thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC) measurements under
inert (N2) and oxidative (synthetic air) atmospheres. Three new products were synthesized and characterized by GC/MS, 1H and 31P NMR. The analyses were focused on the onset (T
e) and offset temperature (T
o) of degradation of the films, and on the maximum degradation temperature (T
MAX). It was observed that the thermal stability of the films increased with the addition of the thiophosphate ester antioxidants,
which indicates that CNSL could be used as a natural source of phenolic material for the synthesis of antioxidants. 相似文献
73.
Sugijanto NE Diesel A Rateb M Pretsch A Gogalic S Zaini NC Ebel R Indrayanto G 《Natural product communications》2011,6(5):677-678
A new macrolactone glycoside, lecythomycin (1), 23-methyl-3-(1-O-mannosyl)-oxacyclotetracosan-1-one, was isolated from the endophytic fungus Lecythophora sp. (code 30.1), an endopyte of the Indonesian plant Alyxia reinwardtii. The structure of 1 was elucidated on the basis of NMR spectroscopic and mass spectrometric data. The isolated compound displayed antifungal activity against strains of Aspergillus fumigatus and Candida kruzei at minimal inhibitory concentrations (MIC) of 62.5-125 microg/mL. 相似文献
74.
Selma Toker Gülesen Üstündağ Şiray Selahattin Kaçıranlar 《Statistics & probability letters》2013,83(10):2391-2398
We carry out the idea of inequality constrained least squares (ICLS) estimation of Liew (1976) to the inequality constrained ridge regression (ICRR) estimation. We propose ICRR estimator by reducing the primal–dual relation to the fundamental problem of Dantzig and Cottle, 1967, Cottle and Dantzig, 1974 with Lemke (1962) algorithm. Furthermore, we conduct a Monte Carlo experiment. 相似文献
75.
Selma Khebbache-Hadji Christian Prins Alice Yalaoui Mohamed Reghioui 《Central European Journal of Operations Research》2013,21(2):307-336
This work deals with a new combinatorial optimization problem, the two-dimensional loading capacitated vehicle routing problem with time windows which is a realistic extension of the well known vehicle routing problem. The studied problem consists in determining vehicle trips to deliver rectangular objects to a set of customers with known time windows, using a homogeneous fleet of vehicles, while ensuring a feasible loading of each vehicle used. Since it includes NP-hard routing and packing sub-problems, six heuristics are firstly designed to quickly compute good solutions for realistic instances. They are obtained by combining algorithms for the vehicle routing problem with time windows with heuristics for packing rectangles. Then, a Memetic algorithm is developed to improve the heuristic solutions. The quality and the efficiency of the proposed heuristics and metaheuristic are evaluated by adding time windows to a set of 144 instances with 15–255 customers and 15–786 items, designed by Iori et al. (Transport Sci 41:253–264, 2007) for the case without time windows. 相似文献
76.
Mohamed S. Behalo Ermelinda Bloise Giuseppe Mele Antonio Salomone Francesco Messa Luigi Carbone Selma Elaine Mazzetto Diego Lomonaco 《Journal of heterocyclic chemistry》2020,57(2):768-773
A green synthesis of benzoxazines, based upon reaction of cardanol with formaldehyde and primary amines, is achieved in high yields using choline chloride-urea mixture as deep eutectic solvent. Then, it is demonstrated how the cardanol-based benxoxazines can be employed as only component for the preparation of a nanovesicular systems. 相似文献
77.
Murat Ozdemir Aykut Kul Selma Ozilhan Olcay Sagirli 《Biomedical chromatography : BMC》2020,34(11):e4936
Acamprosate is a medication used to treat alcohol dependence. Therapeutic drug monitoring is important in drugs for the treatment of substance-related disorders. Therefore, in this study, a new selective, very simple and rapid ultra-performance liquid chromatography–tandem mass spectrometer method was developed for the therapeutic drug monitoring of acamprosate. The developed method allows the determination of acamprosate in human plasma. The method was validated in terms of selectivity and linearity, which was in the range of 100–1,200 ng/ml for acamprosate. Intra-assay and inter-assay accuracy and precision were within the acceptable limits of the Eueopean Medicines Agency guideline. The lower limit of quantitation was 100 ng/ml for acamprosate. The developed method was successfully applied for therapeutic drug monitoring in patient plasma samples. 相似文献
78.
Synthesis,spectral, theoretical studies and in vitro antimicrobial activities of novel diphenyltin(IV) complexes of Schiff bases derived from phenacylamine
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Gökhan Şirikci Nilgün Ancın Selma Gül Öztaş Gülgün Yenişehirli Nurşen Altuntaş Öztaş 《应用有机金属化学》2014,28(7):537-544
A series of new diphenyltin(IV) complexes of the type Ph2SnL (L1: N‐phenacyl‐5‐bromosalicylideneimine, Ph2SnL1; L2: N‐phenacyl‐3,5‐dichlorosalicylideneimine, Ph2SnL2; L3: N–phenacyl‐4‐methoxysalicylideneimine, Ph2SnL3) were synthesized and characterized by elemental analysis, IR, 1H, 13C, 119Sn NMR spectroscopy and mass spectrometry techniques. The C―Sn―C angles in the complexes were calculated using equations with the 1J(117/119Sn―13C) values from 13C NMR spectra. The possible structures, NMR and electronic properties of the studied molecules were calculated through density functional theory and results compared with experimental data. All the complexes were found to be mildly active against several microorganisms and some fungi. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
79.
The oil agglomeration of quartz with sodium oleate in the presence of calcium and magnesium ions comprises three consecutive stages: adsorption of cations onto quartz surfaces, which leads to coagulation of the suspension, shear flocculation with sodium oleate and finally, agglomeration of flocs by kerosene. The effects of pH and cation concentration on these stages were investigated and the results were presented comparatively. It was found that all the stages of oil agglomeration of quartz exhibited sharp dependences on pH and cation concentration. That is, these stages generally took place in the pH and concentration ranges in which hydroxy complexes of the cations existed in the suspension. In the case of magnesium ion, the coagulation, shear flocculation and especially oil agglomeration of quartz improved after precipitation of hydroxide. These species of calcium and magnesium ions formed at high pH were adsorbed on the negatively charged surface of quartz, as a result of which the adsorption of sodium oleate became possible and thus the shear flocculation of the particles was achieved. Thereafter, the hydrophobic quartz flocs could be agglomerated by kerosene as bridging liquid. The increase in the shear flocculation efficiency depending on the increase of surface hydrophobicity enhanced the oil agglomeration of quartz with kerosene. The maximum recoveries for all the stages of the quartz were obtained in the presence of 10(-3) M magnesium and 5x10(-3) M calcium ions at pH 11. However, some differences in the behavior of shear flocculation and oil agglomeration of quartz suspension were observed above 10(-3) M concentration of magnesium ion. 相似文献
80.