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排序方式: 共有101条查询结果,搜索用时 15 毫秒
1.
Molecular Structure,Vibrational Spectra,Molecular Docking,and ADMET Study of Cellulose Triacetate II
Celik Sefa Demirag A. Demet Ozel Aysen E. Akyuz Sevim 《Optics and Spectroscopy》2020,128(8):1138-1150
Optics and Spectroscopy - People have started to look for alternative sources because of the health problems created by petrochemical products used in all areas of human life and environmental... 相似文献
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Dr. İlhan Sevim Dr. Wolf Matthias Pankau Prof. Dr. Günter von Kiedrowski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(41):9032-9035
We re-evaluate our claim of a high diastereoselectivity in the self-relicating Diels–Alder reaction between maleimide 1 and fulvene 3 . It was shown that the system has a diastereoselectivity of 1.8:1 for NN-4 : NX-4 , which is contrary to the 16:1 ratio claimed by Dieckmann et al. The analysis of 1H NMR monitoring of the reaction revealed that both replicators show sigmoidal growth which is typical for auto-catalytic systems. 相似文献
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Mixed matrix materials, containing poly(dimethylsiloxane), phosphine oxide-based polyimide, and zeolite Y were prepared by means of blending hybridisation. The thermal stability of the materials and the hydrophobic properties were enhanced. The decrease in the glass transition temperature of the materials with the increase in poly(dimethylsiloxane) content supported the polymer-chain flexibility. The pristine polyimide and the zeolite-filled polyimide exhibited the highest transparency. Fourier transform infrared (FTIR) spectroscopy confirmed that the increase in the amount of the lowest molecular mass poly(dimethylsiloxane) ingredient indicated strong alkyl and Si-O-Si stretching modes, whilst the alkyl and Si-O-Si stretching intensity decreased in the presence of the highest amount of and the highest molecular mass poly(dimethylsiloxane). The hydrophobic poly(dimethylsiloxane) moiety created an inverse relationship between the porosity of the materials (surface roughness) and the hydrophilicity. The nanocrystallite domain, identified by X-ray diffraction analysis (XRD) and possessing an exotherm crystallisation peak, occurred in the lowest amount of poly(dimethylsiloxane) with the highest molecular mass-based hybrid material. The nanocrystallite enhanced the storage modulus as determined by the dynamic mechanical analyser (DMA). The nanocrystalline formation resulted in a slight increase in the alkyl stretching and the Si-O-Si stretching of the lowest amount of and the highest molecular mass poly(dimethylsiloxane)-containing material over those of the lowest molecular mass poly(dimethylsiloxane) in the same amounts of material involved. 相似文献
5.
Akyuz Sevim Celik Sefa Usta Abdullah Taner Ozel Aysen E. Yılmaz Gözde Yılmaz Salih 《Optics and Spectroscopy》2020,128(8):1318-1327
Optics and Spectroscopy - Endometriosis is a benign gynecologic disorder. It is particularly common among young women and may make pregnancy difficult. In this study molecular level... 相似文献
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Cemalettin Baltacı Huri İlyasoğlu Sevim Beyza Öztürk Sarıkaya Sevda Cavrar Nurettin Yaylı 《Accreditation and quality assurance》2011,16(10):507-513
A proficiency test (PT) was organized for quality control analysis of black tea. Test materials for the analyses of total
content of powder tea, moisture, total ash, acid-insoluble ash, water-soluble ash, alkalinity of water-soluble ash, water
extract, crude fiber and caffeine were sent to the participant laboratories (n:43) in 2009. The assigned value, standard deviation of the parameters and z-scores of the participant laboratories were calculated using the data reported by the participants. The percentage of the
reported results for analytes was found to be ranged from 67.5 to 100%. Acceptable z-scores were achieved by 80.5–97.5% of the participant laboratories. More than 15% of unacceptable results were obtained for
acid-insoluble ash and caffeine analyses. The quality control material for quality control analysis of black tea was developed
from the remaining material. 相似文献
8.
Synthesis and proton conductivity studies of polystyrene‐based triazole functional polymer membranes
Şehmus Özden Sevim Ünügür Çelik Ayhan Bozkurt 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):4974-4980
In this study, poly(vinylbenzylchloride) (PVBC) was produced by free‐radical polymerization of 4‐vinylbenzylchloride, and then it was functionalized with 3‐amino‐1,2,4‐triazole (ATri) and 1H‐1,2,4‐triazole (Tri). The composition of the polymers was verified by elemental analysis, and the structure was characterized by Fourier transform infrared and 13C‐nuclear magnetic resonance spectra. PVBC was modified by ATri with 68% and Tri with 50% yield. The polymers were doped with trifluoromethanesulfonic acid (TA) at various molar ratios, X = 0.5, 1, 2, and 3 with respect to aminotriazole and triazole units. Proton transfer from TA to the triazole rings was proved with Fourier transform infrared spectroscopy. Thermogravimetric analysis showed that the samples are thermally stable up to approximately 200 °C. Differential scanning calorimetry results illustrated the homogeneity of the materials. Under anhydrous conditions, PVBCATri3TA and PVBCTri3TA showed highest proton conductivity of 0.086 and 0.042 S/cm, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
9.
Sevim Hamamci Alisir Necmi Dege Recep Tapramaz 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(4):388-397
Three new diclofenac‐based copper(II) complexes, namely tetrakis{μ‐2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O:O′}bis(methanol‐κO)copper(II), [Cu2(μ‐dicl)4(CH3OH)2] ( 1 ), bis{2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O,O′}bis(1‐vinyl‐1H‐imidazole‐κN3)copper(II), [Cu(dicl)2(vim)2] ( 2 ), and bis{2‐[2‐(2,6‐dichloroanilino)phenyl]acetato‐κ2O,O′}bis(1H‐imidazole‐κN3)copper(II), [Cu(dicl)2(im)2] ( 3 ) [dicl is diclofenac (C14H10Cl2NO2), vim is 1‐vinylimidazole (C5H6N2) and im is imidazole (C3H4N2)], have been synthesized and characterized by elemental analysis, FT–IR spectroscopy, thermal analysis and single‐crystal X‐ray diffraction. X‐ray diffraction analysis shows that complex 1 consists of dimeric units in which the dicl ligand exhibits a bidentate syn,syn‐μ2 coordination mode linking two copper(II) centres. Complexes 2 and 3 have mononuclear units with the general formula [Cu(dicl)2L2] (L is vim or im) in which the CuII ions are octahedrally coordinated by two L and two dicl chelating ligands. The L and dicl ligands both occupy the trans positions of the coordination octahedron. The different coordination modes of dicl in the title complexes were revealed by Fourier transform IR (FT–IR) spectroscopy. The spin matching between the copper(II) centres in the dimeric [Cu2(μ‐dicl)4(CH3OH)2] units was also confirmed by magnetic data to be lower than the spin‐only value and electron paramagnetic resonance (EPR) spectra. The thermal properties of the complexes were investigated by thermogravimetric (TG) and differential thermal analysis (DTA) techniques. 相似文献
10.
Single and dual substituent correlation analysis were applied to study transmission of substituent effects on IR carbonyl and thiocarbonyl stretching frequencies of 4-substituted phenyl-4,5-dihydrobenzo [f] [1,4] oxazepin-3 (2H)-ones (5a–n) and -thiones (6a–n). The substituent effects were estimated on the basis of results of the statistical analysis. The differences among the regression coefficients were discussed in terms of the relative importance of the substituent field and resonance effects. For a better understanding of the results, density functional theory (DFT) calculations were performed to determine the preferred geometry and to calculate the theoretical carbonyl and thiocarbonyl stretching frequencies. 相似文献