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71.
Synthetic lubricating oils based on renewable sources, excluding petroleum, have a great importance among all of the lubricating
oil alternatives that are included in the research field about clean and environmentally friendly lubricating oil technologies.
One of the environmentally friendly lubricating oils is a vegetable oil-based product. In this study, the esterification product
of oleic acid with a fraction of molasses fusel oil as a lubricating oil candidate was determined according to the American
Society for Testing and Materials (ASTM) standard tests. The results indicate that the ester product can be used as an environmental
friendly lubricating oil or lubricating oil additive. 相似文献
72.
A new polymeric resin with glucose sulfonamide functions has been prepared for the extraction of boric acid. This poly (styryl sulfonamide) based resin has been demonstrated to be an efficient sorbent for the removal of boron. The resin had a boron loading capacity of 2.365 mmol.g−1 and showed reasonably rapid sorption ability. Splitting of sorbed boron can be achieved by simple acid leaching (2M H2SO4). 相似文献
73.
Filiz Maden Yücel Ertan Yildirim Tuncer Caykara 《Journal of polymer science. Part A, Polymer chemistry》2019,57(10):1140-1146
2‐Hydroxyethyl acrylamide was successfully polymerized via single‐electron transfer initiation on the silicon surface and propagation through the reversible addition–fragmentation chain transfer (SET‐RAFT) polymerization at ambient temperature for different polymerization times. This work is the first time application of the surface‐initiated SET‐RAFT mechanism to afford the preparation of well‐defined poly(2‐hydroxyethyl acrylamide) [poly(HEAAm)] brushes at ambient temperature. The polymerization was well controlled and produced poly(HEAAm) brushes on the silicon surface with a well‐defined target molecular weight. The controlled nature of the polymerization was further demonstrated in the presence of sulfur atoms at the chain ends in X‐ray photoelectron spectroscopy experiments. The grafting density (σ, chains nm?2) and the average distance between grafting points (D, nm) were found to be 0.42 chains nm?2 and 1.74 nm, respectively, indicating moderate grafting density. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1140–1146 相似文献
74.
Bünyamin Karabulut Filiz Düzgün 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(4):1200-1202
The magnetic environments of Cu2+ doped Na+ complex have been identified by electron paramagnetic resonance (EPR) technique. The angular variation of the EPR spectra has shown that two different Cu2+ complexes are located in different chemical environments, and each environment contains one magnetic Cu2+ site occupying substantial positions in the lattice and showing very high angular dependence. The principal g, and the hyperfine structure parameter (A) values of two sets of Cu2+ complex groups are determined. The covalency parameter, mixing coefficients and Fermi-contact term of the complex are obtained, and the ground state wave function of the Cu2+ ion in the lattice has been constructed. 相似文献
75.
B. Meltem Ateş Bülent Zeybek Dr. Mecit Aksu Ümit Ergun Filiz Ercan M. Levent Aksu Orhan Atakol 《无机化学与普通化学杂志》2010,636(5):840-845
Mononuclear nickel(II) complexes were prepared by reaction of the three ONNO type reduced Schiff bases bis‐N,N′‐(2‐hydroxybenzyl)‐1,3‐propanediamine (LHH2), bis‐N,N′‐(2‐hydroxybenzyl)‐2,2′‐dimethyl‐1,3‐propanediamine (LDMHH2), and bis‐N,N′‐[1‐(2‐hydroxyphenyl)ethyl]‐1,3‐propanediamine (LACHH2) with NiII ions in the presence of pseudo halides (OCN–, SCN– and N3–). The complexes were characterized with the use of elemental analyses, IR spectroscopy, and thermal analyses. The molecular structure of one of the complexes was obtained by single‐crystal X‐ray diffraction. The obtained complexes are mononuclear, and a pseudo halide molecule is attached. One of the oxygen atoms of the ligand is in phenolate and the other was in phenol form. According to the thermogravimetry results, it was thought that the pseudo halide thermally detaches from the structure as hydropseudo halide. In azide‐containing complexes an endothermic reaction was observed although the azide group usually decomposes with an exothermic reaction. 相似文献
76.
77.
Bahadir N. Gacal Volkan Filiz Sergey Shishatskiy Sofia Rangou Silvio Neumann Volker Abetz 《Journal of Polymer Science.Polymer Physics》2013,51(16):1252-1261
Polyisoprene‐block‐poly(vinyl trimethylsilane) (PI‐b‐PVTMS) block copolymers having different isoprene contents are successfully chemically modified and characterized by proton nuclear magnetic resonance spectroscopy (1H‐NMR), Fourier transform infrared spectroscopy, gel permeation chromatography, and thermogravimetric analysis. Gas transport properties of the initial block copolymers and their derivatives modified via hydrosilylation and hydrogenation are measured. The modified block copolymers show higher permeabilities for O2 and H2 than the unmodified block copolymers while maintaining similar O2/N2 and H2/N2 selectivities. Hydrosilylation and hydrogenation of block copolymers with a low isoprene content result in a permeability increase for O2 and H2 of 15 to 40%, respectively. Similarly, for block copolymers with high isoprene contents, increases in permeabilities up to 125% are observed compared to initial PI‐b‐PVTMS. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym. Phys. 2013 , 51, 1252–1261 相似文献
78.
79.
Karabi Halder Prokopios Georgopanos Sergey Shishatskiy Volkan Filiz Volker Abetz 《Journal of polymer science. Part A, Polymer chemistry》2018,56(24):2752-2761
In this work, the synthesis of novel polymers of intrinsic microporosity (PIMs) with different degrees of bromine substitution by a free-radical substitution reaction was performed. The synthesized polymers were thoroughly characterized and their bromination degree was verified via nuclear magnetic resonance. The brominated PIMs were investigated by infrared spectroscopy, X-ray diffraction, and density measurements and correlated with their gas transport properties. It was found that with an increase in the bromination degree, the synthesized PIMs exhibited a significant increase in polymer chain packing density which led to reduced fractional free volume and consequent decrease in gas diffusion and permeability coefficients. The change in permeability coefficients caused an improvement in the CO2/N2, CO2/CH4, and O2/N2 ideal permeability selectivities. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2752–2761 相似文献
80.
Filiz Karacan 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(3):685-691
Determination of 90Sr in environmental solid samples is a challenging task because of the presence of so many other radionuclides in samples of interest. This problem was dealt with by radiochemical separation of strontium followed by yttrium separation and Cerenkov counting of the high-energy ??-particle emissions of 90Y in order to quantitate 90Sr. In this work, an improved method is described for the determination of 90Sr in soil samples, through the separation of the daughter 90Y at equilibrium. The procedure is based on the HDEHP solvent extraction in combination with liquid scintillation spectrometry (LSS). A low background Quantulus has been optimized for low level counting of Cerenkov radiation emitted by the hard ??-emitter 90Y. The analytical quality of the method has been checked by analyzing IAEA Soil-375 reference materials. The analytical method has also been successfully applied to the determination of 90Sr for moss-soil samples in inter-laboratory exercises through IAEA??s ALMERA network. The chemical recovery for 90Y extraction ranged from 80 to 85% and the counting efficiency was 73% in the window 25?C400 keV. 相似文献