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221.
Okan Zafer Yeşilel İnci İlker Ertan Şahin 《Journal of Inorganic and Organometallic Polymers and Materials》2011,21(1):103-109
New thiophene-2,5-dicarboxylate complexes with the formula of [M(μ-tdc)(pen)2]
n
(M = Ni(II) (1) and Cu(II) (2), pen = propane-1,3-diamine, tdc = thiophene-2,5-dicarboxylate) have been synthesized and characterized by using thermal
(TG/DTG, DTA and MS) analysis, IR and UV–Vis. spectroscopies, magnetic measurement and single crystal X-Ray diffraction techniques.
The Ni(II) and Cu(II) ions are distorted octahedrally coordinated by two oxygen atoms of two bridging thiophene-2,5-dicarboxylate
ligands and four nitrogen atoms of the trans-pen ligands. The polymeric chains are connected together by hydrogen bonds interactions, forming three-dimensional network. 相似文献
222.
Güneş Süheyla Kürkçüoğlu Tuncer Hökelek Mehran Aksel Okan Zafer Yeşilel Hakan Dal 《Journal of Inorganic and Organometallic Polymers and Materials》2011,21(3):602-610
Three new complexes [M(deten)2Ni(μ-CN)2(CN)2]
n
(M = Ni, Cu and Cd, deten = N,N-diethylethylenediamine) have been synthesized and characterized by chemical, thermal analysis, FT-IR and Raman spectroscopies.
The crystal structure of the Cd complex has been determined by X-ray single crystal diffraction. Structural study reveals
that the Ni2+ and Cd2+ ions are located on inversion centers, and adopt slightly distorted square-planar and octahedral geometries, respectively.
In the crystal structure, the intermolecular N–H⋯N hydrogen bonds link the polymeric chains into a two dimensional network.
Vibrational spectral data indicate the presence of two ν(C≡N) for complexes can be assigned to the terminal and bridging cyanides.
The decomposition reaction take places in the temperature range 30–1000 °C in the static air atmosphere. 相似文献
223.
Fatih Semerci Okan Zafer Ye?ilel Ertan ?ahin Yusuf Yerli Ramazan Topkaya 《Journal of Inorganic and Organometallic Polymers and Materials》2011,21(2):261-268
A novel 2D coordination polymer, {[Cu(en)2][Cu(μ3-pydc)2]·6H2O}
n
(1) pyridine-2,3-dicarboxylic acid (pydcH2); ethylenediamine (en), based on the metalloligand [Cu(μ-pydcH)2]
n
, has been prepared and characterized by IR, UV–Vis and ESR spectroscopy, thermal analysis, differential scanning calorimetry
and single crystal X-ray diffraction techniques. The temperature dependent magnetic properties have also been studied. The
pydc ligand exhibits tetradentate-μ3 bridging mode, being coordinated through three carboxylate oxygens and one nitrogen atom. The complex contains two copper(II)
ions that exhibit two different coordination environment with two en and two pydc ligands. The single crystal structure shows
that the complex forms a 3D framework with 2D layers along the c-axis. Van der Waals interactions are responsible for the self-assembly of the layer into a 3D network. 相似文献
224.
This study developed a scalable and straightforward adaptation methodology for melt processing of polypropylene (PP) to provide a high degree of exfoliation of multilayer graphene oxide (GO) by using a high-shear mixer. GO was first produced by an improved and eco-friendly electrochemical exfoliation by using an environmentally friendly aqueous methanesulfonic acid (MSA) and a sodium sulfate salt system to minimize the environmental impact. The produced GOs then were melt blended with PP and their mechanical, thermal, and morphological properties were investigated under different GO loadings to attain ideal configuration and increase interfacial interactions between polymer matrix and reinforcer. Comparisons were made by producing different PP composites using two different GO types produced in salt and acid environments. Additionally, by applying different voltages to salt system, the effect of applied voltage on the properties of both GO material and the composites were discussed. The characterization results indicated that GO obtained in MSA solution caused a 71% increase in flexural modulus and 46% in flexural strength with the addition of 1 wt% GO. The rheological characterization also showed that dispersion and viscosity improved with lower GO loadings compared to neat polymer by providing cost-effective and scalable graphene manufacturing. 相似文献
225.
226.
This study was designed to identify the yeasts in packaged and unpackaged butters and screen antiyeast activity of spices, including marjoram (Origanum majorana L.), summer savory (Satureja hortensis L.), and black cumin (Nigella sativa L.) against the most dominant yeast species in the packaged and unpackaged butters. Mean total yeast populations were 5.40 log CFU/g in unpackaged butter samples and 2.22 log CFU/g in packaged butter samples, indicating better hygienic quality of packaged samples. Forty-nine yeast species were isolated and identified from butter samples with the most prevalent isolates belonging to genera Candida-C. kefyr, C. zeylanoides, and C. lambica-and with moderate number of isolates belonging to genera Cryptococcus, Rhodotorula, Saccharomyces, and Zygosaccharomyces. Black cumin exhibited the highest antiyeast activity against C. zeylanoides and C. lambica species, even inhibited these species, while summer savory inhibited C. kefyr. The results of this study revealed clear antimicrobial potential of black cumin against the yeast species isolated from butters. Marjoram, summer savory, and black cumin could be used as natural antimicrobial agents against spoilage yeasts in food preservation, especially in butter. 相似文献
227.