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Hydrophobic surfaces are also known to have antimicrobial effect by restricting the adherence of microorganisms. However, ceramic products are produced by high temperature processes resulting in a hydrophilic surface. In this study, an industrial ceramic wall tile glaze composition was modified by the inclusion of metallic zinc powder in the glaze suspension applied on the pre-sintered wall tile bodies by spraying. The glazed tiles were gloss fired at industrially applicable peak temperatures ranging from 980 °C to 1100 °C. The fired tile surfaces were coated with a commercial fluoropolymer avoiding water absorption. The surfaces were characterized with SEM, EDS, XRD techniques, roughness, sessile water drop contact angle, surface energy measurements, and standard antimicrobial tests. The surface hydrophobicity and the antimicrobial activity results were compared with that of unmodified, uncoated gloss fired wall tiles. A superhydrophobic contact angle of 150° was achieved at 1000 °C peak temperature due to the formation of micro-structured nanocrystalline zinc oxide granules providing a specific surface topography. At higher peak temperatures the hydrophobicity was lost as the specific granular surface topography deteriorated with the conversion of zinc oxide granules to the ubiquitous willemite crystals embedded in the glassy matrix. The antimicrobial efficacy also correlated with the hydrophobic character.

In the literature, limited studies are available due to the challenges of the detailed microstructural characterization and determination of properties of diesel particulate filters (DPFs). For this reason, the characterization of a commercial DPF was carried out with different techniques with the aim to identify the manufacturing processes, the chemical composition, the microstructure and the mechanical, physical and thermal properties. Scanning electron microscopy (energy-dispersive X-ray spectroscopy, back-scattered electron, secondary electron detectors), X-ray diffraction, universal mechanical testing, Archimedes technique, dilatometer and C-therm thermal conductivity analysis tools were used for the characterization. During DPF regeneration, the tailoring of these properties has crucial effect on the reliability and durability of the filter. The value of the thermal shock resistance parameter group $$\sigma _{\mathrm{f}}/E\alpha $$ was calculated to be 426 K, while thermal conductivity (k) was determined as 1.95 W/mK. When compared to the literature values for dense SiC, the $$\sigma _{\mathrm{f}}/E\alpha $$ value indicated a better thermal shock resistance; however, thermal conductivity was on the limits of an order of magnitude worsening the thermal shock resistance. Therefore, to improve the thermal shock resistance of the filter material, the thermal conductivity value has to be increased to the maximum allowed by the required porosity. The study may lead to tailoring of an optimized SiC DPF material.

The aim of this study was to develop low cost hybrid composites with enhanced mechanical properties by the addition of industrial wall tile and glass fiber wastes into epoxy resin. This process not only reduces the production cost, but also helps to eliminate solid wastes. The detailed characterization of waste particulate fillers was performed by scanning electron microscopy, X-ray diffraction, X-ray fluorescence, laser diffraction, and He gas picnometer techniques. The effects of the ceramic particulates to glass fiber ratio and the particle size of the waste materials on the physical and mechanical properties were determined with a fixed polymer to filler ratio of 40:60. The density, three point bending strength, impact resistance and hardness of the hybrid composites were measured. The results indicated that when the filler particle size increased, the bulk density almost remained unchanged, and the bending strength and impact resistance decreased, while the hardness and flexural modulus were almost constant. Because of the weak matrix-reinforcement interphase, mechanical properties deteriorated with the increasing amount of waste glass fiber and better mechanical properties were achieved with the use of finer particles. As a result of incorporation of industrial wastes such as ground ceramic wall tile and glass fiber instead of expensive fillers, low cost reinforcement of the hybrid epoxy matrix composites was achieved. POLYM. COMPOS., 2017. © 2017 Society of Plastics Engineers

Biocidal antimicrobial molecular barrier (BAMB) solutions are known to provide antimicrobial effect on the surfaces in industrial applications. However, there has been a lack of scientific reports about the subject in the literature. In this study, in order to impart an antimicrobial surface property on ceramic surfaces, a BAMB solution was applied on gloss fired ceramic wall tile substrates and the surface antimicrobial activity results were compared with that of plain wall tiles (without BAMB application). The ceramic surfaces were cleaned, and stove dried at120°C prior to spray coating with a BAMB solution. The coated substrates were dried in the ambient. The intactness of the coatings was checked with the bromophenol blue test. The microstructural and molecular characterization of the BAMB coated surfaces were carried out with SEM imaging and surface FTIR, respectively. The antimicrobial activity tests of the surfaces were conducted according to ASTM E2180-07 (Standard Test Method for Determining the Activity of Incorporated Antimicrobial Agent in Polymeric or Hydrophobic Materials). The microorganisms used were Staphylococcus aureus (ATCC 6538) and Pseudomonas aeruginosa (ATCC 15442) bacteria. The BAMB coated surfaces showed less flocculent bacterial growth in comparison to uncoated ceramic surfaces leading to the conclusion that the BAMB improved the antimicrobial property.

α:β-SiAlON and 10, 17, and 25 wt% TiN particle reinforced composites were produced by a gas pressure sintering method. The densification behavior, phase and microstructural evolution, mechanical and thermal shock behavior of materials were investigated. The TiN incorporation had significant influence on the matrix microstructure and improved fracture toughness of the material. The highest fracture toughness was obtained for the composite with 25 wt% TiN ( K 1c : 8.2±0.2 MPa m 1/2 ). SiAlON–TiN composites showed lower crack formation and propagation compared to the monolithic SiAlON. Above 700 °C passive oxidation took place and provided crack healing by filling the cracks with TiO 2 , and the thermal shock resistance behavior was improved.

Two Solanaceae invasive plant species (Physalis angulata L. and P. philadelphica Lam. var. immaculata Waterfall) infest several arable crops and natural habitats in Southeastern Anatolia region, Turkey. However, almost no information is available regarding germination biology of both species. We performed several experiments to infer the effects of environmental factors on seed germination and seedling emergence of different populations of both species collected from various locations with different elevations and habitat characteristics. Seed dormancy level of all populations was decreased with increasing age of the seeds. Seed dormancy of freshly harvested and aged seeds of all populations was effectively released by running tap water. Germination was slightly affected by photoperiods, which suggests that seeds are slightly photoblastic. All seeds germinated under wide range of temperature (15–40 °C), pH (4–10), osmotic potential (0 to −1.2 MPa) and salinity (0–400 mM sodium chloride) levels. The germination ability of both plant species under wide range of environmental conditions suggests further invasion potential towards non-infested areas in the country. Increasing seed burial depth significantly reduced the seedling emergence, and seeds buried below 4 cm of soil surface were unable to emerge. In arable lands, soil inversion to maximum depth of emergence (i.e., 6 cm) followed by conservational tillage could be utilized as a viable management option.

WOS:000385507000027 PubMed: 27741269 Invasive plants are recognized for their impressive abilities to withstand adverse environmental conditions however, all invaders do not express the similar abilities. Therefore, survival, growth, nutrient uptake and fecundity of two co-occurring, invasive Physalis species were tested under water and salinity stresses, and different soil textures in the current study. Five different water stress levels (100, 75, 50, 25, and 12.5% pot water contents), four different soil salinity levels (0, 3, 6, and 12 dSm(-1)) and four different soil textures (67% clay, 50% clay, silt clay loam and sandy loam) were included in three different pot experiments. Both weeds survived under all levels of water stress except 12.5% water contents and on all soil types however, behaved differently under increasing salinity. The weeds responded similarly to salinity up till 3 dSm(-1) whereas, P. philadelphica survived for longer time than P. angulata under remaining salinity regimes. Water and salinity stress hampered the growth and fecundity of both weeds while, soil textures had slight effect. Both weeds preferred clay textured soils for better growth and nutrient uptake however, interactive effect of weeds and soil textures was non-significant. P. angulata accumulated higher K and Na while P. philadelphica accrued more Ca and Mg as well as maintained better K/Na ratio. P. angulata accumulated more Na and P under salinity stress while, P. philadelphica accrued higher K and Mg, and maintained higher K/Na ratio. Collectively, highest nutrient accumulation was observed under stress free conditions and on clay textured soils. P. philadelphica exhibited higher reproductive output under all experimental conditions than P. angulata. It is predicted that P. philadelphica will be more problematic under optimal water supply and high salinity while P. angulata can better adapt water limited environments. The results indicate that both weeds have considerable potential to further expand their ranges in semi-arid regions of Turkey.

WOS: 000376800800012, The Late Miocene was characterized by high global temperatures and partly to nearly complete desiccation of the Mediterranean Sea throughout the latter part of the Messinian age (the Messinian salinity crisis). The Late Miocene marine Mediterranean Sea area has been widely studied from different perspectives, but terrestrial paleoenvironmental and paleoclimatic records from the Mediterranean area are highly limited in their spatial range. To this end, the paleosols, dolocrete and fluvial sedimentary rocks of the Komisini Formation in the northwestern part of the Tuzgolu basin are described in detail. Six lithofacies were identified as (A) clast-supported gravel, (B) massive (pebbly) sandstone, (C) massive mudstone, (D) disrupted mud, (E) disrupted conglomerate, and (F) disrupted matrix-supported conglomerate. The siliciclastic facies were interpreted as braidplain, and the distal part of braidplain deposits is associated with an ophiolitic area while the disrupted mud and disrupted conglomerate were identified as three types of paleosols: Inceptisols, Aridisol and Vertisols. The calcretes occur in the paleosols in nodular, powder, and massive forms. Clay minerals include smectite, chlorite, palygorsldte, illite, and serpentine. Gypsum, smectite and chlorite are dominant minerals at the base and middle part of the section, whereas palygorskite and illite appear as the prevailing clay minerals in the upper sections. Smectite, illite and palygorskite precipitated in a vadose zone from strongly evaporated alkaline water rich in Si, Ca and Mg and poor in Al at increased temperatures and at an advanced stage of dolocrete and paleosol formation. K, Si, Mg, Al + Fe and Ca are required for smectite, illite, palygorskite and calcification. Given the increase in Ba, Cr, Ni and Co, these cations might have originated from ophiolite, carbonate and volcanic units. As a consequence, the vertical distribution of clay mineral types suggests the variations of paleoclimatic conditions during the deposition, and the relationships among the type of host rock, paleosol and dolocrete, which corresponds to nearly complete desiccation of the Mediterranean Sea. (C) 2016 Elsevier B.V. All rights reserved., Scientific and Technological Research Council of Turkey (TUBITAK) [104Y070], The author is greatly indebted to Professor Dr. Warren Huff, University of Cincinnati and anonymous reviewers for their critical reviews and suggestions which improved the manuscript. We are also extremely grateful to Professor Dr. Markus Egli for his editorial comments and suggestions. This study was financially supported by the Scientific and Technological Research Council of Turkey (TUBITAK) within the framework of Project No. 104Y070.

Microstructural and phase analyses of corroded frit furnace refractories forming the side walls and the bottom of an industrial frit furnace is reported in this study. Reflected light optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, and x-ray diffraction tools were used for the analyses. The microstructural analysis in combination with the saturation solubilities information in the phase diagrams was used to predict the corrosion behavior of the refractories. The frit and the refractory types were compared qualitatively for the dissolution potential and corrosion mechanisms. The dissolution of the refractory material was direct (congruent) for both the side wall refractories and bottom pavers. The first push exudation phenomenon was determined to be effective for the increase of porosity and pore dimensions which in turn caused accelerated wear rates when combined with corrosion. The corrosive potential of the transparent frit for corundum, mullite, and glassy phase in the refractories was determined to be excessive. The dissolution of these species in the molten transparent frit was predicted to start at temperatures between 1000-1340 o C while the operating temperature was 1470 o C. The decrease in the extent of corrosion by zirconia inclusion either in the refractories or in the molten glass compositions was qualitatively discussed.

Bu calismada, madimak (Polygonum cognatum Meissn.) tohumunun bazi fiziksel ozelliklerine nem iceriginin etkisi belirlenmistir. Nem icerikleri sirasiyla %7,95; 13,68 ve 19.14 (kuru baza gore) olarak belirlendi. Ortalama geometrik ortalama cap, birim agirlik, kuresellik, 1000 dane agirligi ve dogal yigiilma acisi nem iceriginin %7,95’den %19.14’e kadar artisina gore sirasiyla 1,85’den 1.94 mm’e, 0,0040’dan 0.0046 g’a, %66.21’den 67.37’e, 3,32’den 3,74 g’a kadar ve 18,36’dan 25,00°’ye kadar degisiklik gostermistir. Tohum hacmi, yigin hacim agirligi ve yuzey alani degerleri nem icerigi artisina gore; 3,357 mm3’den 3,894 mm3’e, 696,11 kg m-3’den 707,73 kg m-3’e ve 10,786’dan 11,867 mm2’ e artis gosterirken, tane hacim agirligi ve porozite degerleri; %57,93’den %40,16’a 1654,69 kg m-3’den 1182,64 kg m-3’e azalmistir. Statik surtunme katsayisi degerleri, farkli yuzeyler icin nem icerigi artisiyla artis gostermistir. Madimak tohumlari cok kucuk boyutlarda oldugu icin yuksek nem iceriklerinde kolayca ayrilabilir, dolayisiyla bu kucuk tohumlarin ekimini ve cimlenme oraninin artisina yardimci olabilir.