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31.
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Inverse gas chromatography (IGC) was applied to characterize the surface of sepiolite. The adsorption thermodynamic parameters (the standard enthalpy (ΔH 0), entropy (ΔS 0) and free energy of adsorption (ΔG 0)), the dispersive component of the surface energy (γ S d ), and the acid/base character of sepiolite surface were estimated by using the retention time of different non-polar and polar probes at infinite dilution region. The specific free energy of adsorption (ΔG sp ), the specific enthalpy of adsorption (ΔH sp ), and the specific entropy of adsorption (ΔS sp ) of polar probes on sepiolite were determined. ΔH sp were correlated with the donor and modified acceptor numbers of the probes to quantify the acidic K A and the basic K D parameters of the sepiolite surface. The values obtained for the parameters K A and K D indicated an acidic character for sepiolite surface. 相似文献
33.
Asım Davulcu Hüseyin Benli Yasin Şen M. İbrahim Bahtiyari 《Cellulose (London, England)》2014,21(6):4671-4680
Application of natural dyes for textiles is increasing due to awareness of environment, ecology, and pollution control. The purpose of this study is to determine the color, antimicrobial, and fastness properties of cotton fabrics dyed with thyme and pomegranate peel without a mordanting process. In this way, it was planned to avoid use of metallic mordants (heavy-metal salts) and prevent heavy-metal pollution for ecological production. Additionally, a variety of the most commonly used mordants, namely potassium aluminum sulfate, copper(II) sulfate, iron(II) sulfate, and tin(II) chloride, were used for mordanting of cotton fabrics in order to compare the differently mordanted and unmordanted dyed fabrics’ color efficiencies (K/S) and CIE L * a * b * color values. It was found that mordant type had an effect on color efficiency and the color coordinates of fabrics dyed with both thyme and pomegranate fruit peel. Moreover, the antimicrobial properties of the fabrics only dyed directly with thyme and pomegranate peel without any mordanting process were determined to demonstrate the usability of these natural dye sources without use of any mordanting agents. The obtained antimicrobial activities were compared with undyed samples. Undyed samples showed no antimicrobial activity, whereas significant antimicrobial activity was obtained after the dyeing procedure using thyme and pomegranate peel on unmordanted fabrics. Washing, rubbing, perspiration, and lightfastness properties of dyed fabrics were also evaluated. Thyme and pomegranate fruit peel as natural dye sources revealed sufficient results even for unmordanted samples. 相似文献
34.
In this work, a phthalonitrile derivative bearing p-sulfonylphenoxy group at the 3-position has been synthesised. The water-soluble non-peripherally tetrasubstituted zinc (3) and cobalt (4) phthalocyanines were obtained by cyclotetramerisation of this phthalonitrile derivative in the presence of anhydrous metal salts by microwave irradiation. The compounds have been characterised by using FT-IR, 1H NMR, UV–Vis and Mass spectrometry (MS) data. The aggregation behaviours of these compounds were investigated in methanol, DMSO, DMF, and water. We have also studied the aggregation behaviours of the phthalocyanine complex 3 in various DMSO/water mixtures. Additionally, the redox properties of the phthalocyanine complexes were examined in dimethylsulfoxide by voltammetry and in situ spectroelectrochemistry. Redox behaviours of the complexes supported the structures of the complexes. Metal and ring-based reductions were observed for 4 and only ring-based electron transfer processes were observed with 3. 相似文献
35.
Esra Korkmaz Kirakli Gökhan Takan Sinan Hoca F. Zümrüt Biber Müftüler Ayfer Yurt Kılçar Serra Arun Kamer 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(3):595-602
The purpose of this study was to assess SPION’s in vitro radiosensitizer effect at 6MV-energies and to calculate nanoparticle enhancement ratio (NER) of SPIONs. Citrate coated-SPION’s were synthesized. Trypan-blue, metabolic activity tests were performed. Cell cultures were irradiated at 0,2,4,6,8 Gy at 6MV-energy. Clonogenic survival assays, NER calculations were carried out. SPIONs were biocompatible. NERs were cell-line specific and dose dependent. The highest radiosensitization were seen in radiosensitive MCF-7 and MDAH-2447 cells at 2 Gy (NER:1.49 and 1.39 respectively), in relatively radioresistant MDA-MB-231 cells at 4 Gy (NER:1.20). By increasing doses radiosensitizer effect disappeared. There is possibility that by synergistic effect, SPIONs may cause dose-dependent and cell-line specific radiosensitization at 6MV. 相似文献
36.
Aydın Aktaş Ünzile Keleştemur Yetkin Gök Sevgi Balcıoğlu Burhan Ateş Muhittin Aygün 《Journal of the Iranian Chemical Society》2018,15(1):131-139
In this study, a series of unsymmetrically 2-morpholinoethyl-substituted benzimidazolium salts and their Ag(I)NHC complexes were synthesized. The 1,3-dialkylbenzimidazolium salts (1a–d) were synthesized in dimethylformamide at 80 °C temperature from the N-(2-morpholinoethyl)benzimidazole and alkyl halides. The Ag(I)NHC complexes (2a–d) were synthesized in dichloromethane at room temperature from the benzimidazolium salts and Ag2O. All compounds were characterized by spectroscopic techniques (NMR and FT-IR) and elemental analyses. Also, the salt 1c and complex 2c were characterized by single-crystal X-ray crystallography. Anticancer activities of 2-morpholinoethyl-substituted benzimidazolium salts and Ag(I)NHC complexes were investigated against the MCF-7 breast cancer cell line, and the IC30 and IC50 values of these compounds were found to be in the range of 241–490 and 6–14 µM, respectively. 相似文献
37.
A Silk Fibroin and Peptide Amphiphile‐Based Co‐Culture Model for Osteochondral Tissue Engineering 下载免费PDF全文
Anıl S. Çakmak David L. Kaplan Menemşe Gümüşderelioğlu 《Macromolecular bioscience》2016,16(8):1212-1226
New biomaterials with the properties of both bone and cartilage extracellular matrices (ECM) should be designed and used with co‐culture systems to address clinically applicable osteochondral constructs. Herein, a co‐culture model is described based on a trilayered silk fibroin‐peptide amphiphile (PA) scaffold cultured with human articular chondrocytes (hACs) and human bone marrow mesenchymal stem cells (hBMSCs) in an osteochondral cocktail medium for the cartilage and bone sides, respectively. The presence of hACs in the co‐cultures significantly increases the osteogenic differentiation potential of hBMSCs based on ALP activity, RT‐PCR for osteogenic markers, calcium analyses, and histological stainings, whereas hACs produces a significant amount of glycosaminoglycans (GAGs) for the cartilage region, even in the absence of growth factor TGF‐β family in the co‐culture medium. This trilayered scaffold with trophic effects offers a promising strategy for the study of osteochondral defects.
38.
Emine Özge Karaca Mitat Akkoç Muhammad Nawaz Tahir Cengiz Arıcı Fatma İmik Nevin Gürbüz Sedat Yaşar İsmail Özdemir 《Tetrahedron letters》2017,58(36):3529-3532
A series of seven-membered ditopic ring-expanded N-heterocyclic carbene (dre-NHC) precursors, bearing sterically demanding and electron-rich aryl groups, were synthesised in moderate yields via the reaction of 1,2,4,5-tetrakis(bromomethyl)benzene with the corresponding N,N′-diarylformamidines in the presence of K2CO3 in acetonitrile under an air atmosphere. All new compounds were characterised by HRMS, NMR spectroscopy, and microanalysis, as well as X-ray crystallography for compound 1c. The development of an efficient catalytic system for the Suzuki-Miyaura coupling reaction of aryl chlorides with various boronic acids was also investigated using the in situ generated dre-NHC ligands. 相似文献
39.
40.
Mert Kılınç Gaye Ö. Çakal Sertan Yeşil Göknur Bayram İnci Eroğlu Saim Özkar 《Journal of Crystal Growth》2010,312(22):3361-3366
Synthesis of zinc borate was conducted in a laboratory and a pilot scale batch reactor to see the influence of process variables on the reaction parameters and the final product, 2ZnO·3B2O3·3.5H2O. Effects of stirring speed, presence of baffles, amount of seed, particle size and purity of zinc oxide, and mole ratio of H3BO3:ZnO on the zinc borate formation reaction were examined at a constant temperature of 85 °C in a laboratory (4 L) and a pilot scale (85 L) reactor. Products obtained from the reaction in both reactors were characterized by chemical analysis, X-ray diffraction, particle size distribution analysis, thermal gravimetric analysis and scanning electron microscopy. The kinetic data for the zinc borate production reaction was fit by using the logistic model. The results revealed that the specific reaction rate, a model parameter, decreases with increase in particle size of zinc oxide and the presence of baffles, but increases with increase in stirring speed and purity of zinc oxide; however, it is unaffected with the changes in the amount of seed and reactants ratio. The reaction completion time is unaffected by scaling-up. 相似文献