Search

Kil minerallerinin düzgün dağılımı, polimer kilnanokompozit üretiminde önemli bir role sahiptir. Bu bakımdan, kompozitlerininterkale/eksfoliye yapılarını elde etmek için kilin farklı organomodifikasyonyöntemleri denenmiştir. Bu çalışmada, Çanakkale bentonitinin tetrametilamonyumklorür (TMAC), hekzadesilpiridinyum klorür (HDPC), hekzadesiltrimetilamonyumbromür (HDAB), feniltrimetilamonyum klorür (PMAC) olmak üzere dört farklıkuvaterner amonyum tuzu ile organomodifikasyonu incelenmiştir.Organobentonitler Fourier transform infrared spektroskopi (FTIR), X-ışınıkırınımı (XRD) analizi ve termogravimetrik analiz (TGA) ile karakterizeedilmiştir. HDAB ve HDPC tuzları kullanılarak bentonitin bazal aralığı 14.9Å'dan sırasıyla 20.7 Å'a ve 21.4 Å'a kadar artırılmıştır. Bununla birlikte,diğer modifiye edici tuzlar d-aralıklarında önemli değişikliklere nedenolamamışlardır., The improved dispersion of clay mineralshas an essential role for polymer clay nanocomposite manufacturing. In thisregard, different organomodifications of clay have been attempted to obtainintercalated/exfoliated structures of composites. In present study, Çanakkalebentonite was organically modified by four different quaternary ammonium salts:tetramethylammonium chloride (TMAC), hexadecylpyridinium chloride (HDPC),hexadecyltrimethylammonium bromide (HDAB), phenyltrimethylammonium chloride(PMAC). Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD)analysis and thermogravimetric analysis (TGA) were performed to characterizethe organobentonites. The results revealed that there is an increment of basalspacing of bentonite with HDAB and HDPC salts from 14.9Å to 20.7 Å and 21.4 Å, respectively. However, othermodifiers cannot lead to significant changes in d-spacings.

Here, we present quartz sandstone samples observed from widely distributed, white-coloured, uncemented units in and around Matsena village located in northwest of Chad Basin, NE Nigeria. The mineralogical, geochemical compositions and micromorphological characteristics of the quartz sandstones were determined by X-ray diffraction (XRD), X-ray fluorescence (XRF), stereo microscope and scanning electron microscopy (SEM), respectively. The spectral distribution of these lithological units was determined by using Landsat 8 OLI and image enhancement techniques. XRD and XRF analyses reveal that the quartz sandstone samples can be characterized as mature-super mature by their high SiO2 contents. General appearances of the quartz grains under SEM show rounded to sub-rounded and to a lesser extent subangular habits with dish-shaped cavities, V-shaped depressions, mature conchoidal fractures and linear grooves, all of which suggest the mechanical impact on quartz grains from aeolian, fluvial-marine and colluvial environments., Burada, KD Nijerya Çad Havzasının kuzeybatısında yer alan Matsena yerleşimi civarından kuvars kumtaşı örneklerini sunuyoruz. Bu kuvars kumtaşlarının mineralojik, jeokimyasal bileşimi ve mikromorfolojik özellikleri sırasıyla XRD, XRF, stereo mikroskop ve SEM analizleri ile belirlenmiştir. Bu litolojik birimlerin alansal dağılımı Landsat 8 OLI ve görüntü iyileştirme teknikleri ile belirlenmiştir. XRD ve XRF analizleri, kuvars kumtaşı örneklerini, yüksek SiO2 içeriğinden dolayı olgun- ileri olgun olarak karakterize edilebileceğini göstermiştir. Kuvars tanelerinin SEM ile genel görünümleri yuvarlaktan yarı yuvarlak ve daha az oranda yarı köşeli morfolojide; çanak şekilli boşluklu, v şeklinde çukurlu, gelişmiş konkoidal çatlaklı ve lineer çizgili morfolojisini gösterir; bunlar da kuvars taneleri üzerinde mekanik etkinin eoliyen, flüvyal-denizel ve kolüvyal ortamlardan geliştiğini önermektedir.

Kil minerallerinin düzgün dağılımı, polimer kil nanokompozit üretiminde önemli bir role sahiptir. Bu bakımdan, kompozitlerin interkale/eksfoliye yapılarını elde etmek için kilin farklı organomodifikasyon yöntemleri denenmiştir. Bu çalışmada, Çanakkale bentonitinin tetrametilamonyum klorür (TMAC), hekzadesilpiridinyum klorür (HDPC), hekzadesiltrimetilamonyum bromür (HDAB), feniltrimetilamonyum klorür (PMAC) olmak üzere dört farklı kuvaterner amonyum tuzu ile organomodifikasyonu incelenmiştir. Organobentonitler Fourier transform infrared spektroskopi (FTIR), X-ışını kırınımı (XRD) analizi ve termogravimetrik analiz (TGA) ile karakterize edilmiştir. HDAB ve HDPC tuzları kullanılarak bentonitin bazal aralığı 14.9 Å'dan sırasıyla 20.7 Å'a ve 21.4 Å'a kadar artırılmıştır. Bununla birlikte, diğer modifiye edici tuzlar d-aralıklarında önemli değişikliklere neden olamamışlardır The improved dispersion of clay minerals has an essential role for polymer clay nanocomposite manufacturing. In this regard, different organomodifications of clay have been attempted to obtain intercalated/exfoliated structures of composites. In present study, Çanakkale bentonite was organically modified by four different quaternary ammonium salts: tetramethylammonium chloride (TMAC), hexadecylpyridinium chloride (HDPC), hexadecyltrimethylammonium bromide (HDAB), phenyltrimethylammonium chloride (PMAC). Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis and thermogravimetric analysis (TGA) were performed to characterize the organobentonites. The results revealed that there is an increment of basal spacing of bentonite with HDAB and HDPC salts from 14.9 Å to 20.7 Å and 21.4 Å, respectively. However, other modifiers cannot lead to significant changes in d-spacings

Gul, Murat/0000-0003-1555-6426 WOS: 000540792000001 The uniqueness of the spits comes from their special coastal geomorphology. Spit's evolution is controlled by the fragile environmental conditions, the sediment input, long shore currents, wave, wind and river processes. The Kizkumu Spit, one of the attractive examples (400 m long; 18-48 m wide) is located in an environmentally protected area in southwestern Turkey (Datca-Marmaris). Extending 50 cm below the sea as a red carpet, the spit with its distinctive appearance and mysterious history enhance the site's attractiveness which brings on the possible anthropogenic effects as overpopulation during summer tourism and the lower sediment influx from improper marine structure. This study characterizes the spit formation via recent and the past satellite images, geological and topographical maps to better figure out the protection pathways. Six locations were defined and twelve beach sediments in total were sampled. The particle size distribution by sieving together with micro-imaging the sediments are combined with the statistical analyses. Mode values from sieve analysis and the red-coloured sediments along the coast which are also visible on satellite images point out that the Kizkumu Spit is fed from north (via Kocapinar Stream Delta and its coast) and east (via Bozegri Brook). An uncontrolled sand-drawing from the coast, establishing the breakwaters to prevent the longshore currents and waves onto the coastal structures and experiencing walking along the spit, all cause the dispersion of the sediments and very intense erosion on the spit. The results of this study suggest that immediate protection measures (including spit-monitoring, prevention of sand drawing, limitation of daily tourist activities) should be taken for future sustainability of the Kizkumu spit.