Enhancement of flexural and shear properties of carbon fiber/epoxy hybrid nanocomposites by boron nitride nano particles and carbon nano tube modification

In this study, the effect of boron nitride nano particle (BNNP) and/or carbon nanotube (CNT) adding for epoxy modification upon tensile, flexural and shear properties of epoxy resin and carbon fiber (CF) laminated nanocomposites were investigated. Epoxy based polymer nanocomposites were prepared by conventional casting in stainless steel mold and the CF/epoxy laminated nanocomposites were produced via vacuum assisted resin transfer molding (VARTM). Experimental results showed that the tensile, shear and flexural properties of epoxy nanocomposites and CF/epoxy laminated nanocomposites considerably increased by adding nanoparticle. Scanning electron microscopy (SEM) was utilized in order to determine damage formation of experimented nanocomposite samples. The results of laboratory tests showed that the highest values of mechanical properties were obtained for BNNP-CNT hybrid nanocomposite specimens. Bending stiffness increasement values of BNNP-CNT/Epoxy and BNNP-CNT-Epoxy/CF achieved by 27.5 %, and 38.5 %, respectively. Shear strength increasement for BNNP-CNT/Epoxy and BNNP-CNT-Epoxy/CF were determined by 23 %, and 90 %, respectively.     

Anthropogenic sediments and soils of tells of the Balkans and Anatolia: Composition,genesis, and relationships with the history of landscape and human occupation

Soils and sediments composing Tell Körtik Tepe (Epipaleolithic, Turkey) and Tell Yunatsite (Chalcolithic (Eneolithic), Bulgaria) have been studied with the aim to gain a better insight into their microfabrics, determine the composition of anthropogenic artifacts, and, on this basis, to analyze similarities and distinctions between these objects and the modern soils of urban areas. The methods of micromorphology, scanning electron microscopy with an energy dispersive X-ray microanalyzer, X-ray fluorometry, and other techniques to determine the chemical and physical properties of the soils and sediments have been applied. Two paleosols have been identified in Tell Yunatsite with a total thickness of 9 m: the paleosol buried under the tell and the paleosol in its middle part. Sediments of Tell Körtik Tepe have a total thickness of up to 5 m; their accumulation began at the end of Pleistocene over the surface of buried paleosol. The cultural layer of the tells consists of construction debris mainly represented by a mixture of clay and sand and of domestic wastes with the high content of phosphorus. The major source of phosphorus is calcium phosphate (apatite) of bone tissues. The abundance of various anthropogenic materials in the sediments is clearly seen in thin sections. Even in the paleosols developed within the cultural layer (the mid-profile paleosol in Tell Yunatsite), the amount of microinclusions of bone fragments, charcoal, and burnt clay (ceramics) is very high. Micromorphological data indicate that up to 50% of the layered material filling an Epipaleolithic construction in Tell Körtik Tepe consists of the anthropogenic inclusions: bone fragments, charcoal, etc. The features of pedogenic transformation are present in the sediments. Such sediments can be classified as synlithogenic soils similar to the modern Urbic Technosols. It is shown that the formation of paleosols and sediments of Tell Körtik Tepe took place under extreme environmental conditions—arid climate of the latest Pleistocene climate cooling phase (the Younger Dryas, Tell Körtik Tepe)—and intensive anthropogenic loads (tells Körtik Tepe and Yunatsite).     

Growth promotion of plants by plant growth-promoting rhizobacteria under greenhouse and two different field soil conditions

This study was conducted with sugar beet in greenhouse and field at two soil type with different organic matter (containing 2.4 and 15.9% OM, referred as the low- and high-OM soil) conditions in order to investigate seed inoculation of sugar beet, with five N₂-fixing and two phosphate solubilizing bacteria in comparison to control and mineral fertilizers (N and P) application. Three bacterial strains dissolved P; all bacterial strains fixed N₂ and significantly increased growth of sugar beet. In the greenhouse, inoculations with PGPR increased sugar beet root weight by 2.8-46.7% depending on the species. Leaf, root and sugar yield were increased by the bacterial inoculation by 15.5-20.8, 12.3-16.1, and 9.8-14.7%, respectively, in the experiment of low- and high-OM soil. Plant growth responses were variable and dependent on the inoculants strain, soil organic matter content, growing stage, harvest date and growth parameter evaluated. The effect of PGPR was greater at early growth stages than at the later. Effective Bacillus species, such as OSU-142, RC07 and M-13, Paenibacillus polymyxa RC05, Pseudomonas putida RC06 and Rhodobacter capsulatus RC04 may be used in organic and sustainable agriculture.     

Freeze Injure and Antioxidant Enzyme Activity of Grapevine (<Emphasis Type="Italic">Vitis Vinifera</Emphasis>) Under Bio-Boron Fertilizer Applications

This study was conducted to determine the effects of plant growth promoting bacteria (PGPR) and boron (Bio-B) on the plant freeze injury, antioxidant enzyme activity and fruit yield of grapevine cultivar. The experimental plot was a completely randomized design with 5 replicates. As a trial model Bio-B and control were used as fertilizer agent. Bio-B fertilizer has been applied in different ways as soil?+?foliar, soil and foliar application methods to grapevine plants. Data through 2 years trials results showed that the use of Bio-B significantly decreased freeze injury and increased antioxidant enzyme activity of grapevine leaf. The highest damage rate at control group occurred with ?20?^°C and 94.89% ratio. In the same temperature degree at grape plant, the damage ratio of the Bio-B application from soil decreased by 21.55%; the application from leaf by 25.53% and with the application from soil?+?leaf by 26.24%. In addition to this, compared with control, in the CAT, POD and SOD enzyme activities increases occurred with the ratios as 28.57%, 22.05% and 39.25%, respectively. Generally, as results of this study under field conditions, Bio-B fertilizer application decreased freeze injure and increased antioxidant enzyme activity of the grapevine plant.     

In vitro antioxidant, antimicrobial, and antiviral activities of the essential oil and various extracts from herbal parts and callus cultures of Origanum acutidens

The essential oil and various extracts obtained from Origanum acutidens and methanol extracts (MeOH) from callus cultures have been evaluated for their antioxidative, antimicrobial, and antiviral properties. The essential oil exhibited strong antimicrobial activity with a significant inhibitory effect against 27 (77%) of the 35 bacteria, 12 (67%) of the 18 fungi, and a yeast tested and moderate antioxidative capacity in DPPH and beta-carotene/linoleic acid assays. GC and GC-MS analyses of the oil resulted in the identification of 38 constituents, carvacrol being the main component. The MeOH extracts obtained from herbal parts showed better antioxidative effect than that of butylated hydroxytoluene (BHT), whereas callus cultures also exhibited interesting antioxidative patterns. Concerning antiviral activity, none of the extracts inhibited the reproduction of influenza A/Aichi virus in MDCK cells. The MeOH extracts from herbal parts inhibited the reproduction of HSV-1, and also callus cultures exerted slight antiherpetic effect.     

Lactobacillus spp. bacteria as probiotics in gilthead sea bream (Sparus aurata, L.) larvae: Effects on growth performance and digestive enzyme activities

In this study, the influence of commercial probiotic, Lactobacillus spp., supplementation was investigated on growth parameters and digestive enzyme activities in gilthead sea bream, Sparus aurata, during larval development. All experiments were triplicated and designed in three different administrations of probiotic from 3 days after hatching (DAH) concurrently with starting of exogenous feeding. In the first group, probiotic was added to live food (rotifer and Artemia). In the second group, probiotic was supplemented directly to both live food and water. In the third group, probiotic was added directly to water. Also, no probiotic treatment was maintained in control group. Total bacterial counts among probiotic probiotic-supplemented groups were significantly different from total bacterial counts in controls in water and digestive tract of larvae (p < 0.05). The mean of total bacterial counts in control was approximately 4 × 10⁴-fold increased from the experimental groups in the sea water (p < 0.05). Besides, mean digestive enzyme activities of all probiotics treatment groups were significantly different (p < 0.05) with that of the control. Except probiotic water supplementation group, in all treatments, the specific activities of pancreatic and intestinal enzymes were significantly higher (p < 0.05) in larvae to which probiotic had been supplemented by live food and live food with water. Also, S. aurata larvae that had probiotic administered by live food with water demonstrated significant (p < 0.05) increases in both survival (13–105% higher) and specific growth rate (2–9% higher) as compared to controls. As a result, supplementation of probiotic to directly tank water could not significantly increase growth parameters and digestive enzyme activities and therefore, administration of probiotics by this method would not be effective in terms of husbandry parameters and nutritional condition.     

Effects of dietary chromium picolinate supplementation on performance and plasma concentrations of insulin and corticosterone in laying hens under low ambient temperature

This experiment was conducted to evaluate the effects of chromium (chromium picolinate) on performance and plasma concentrations of insulin and corticosterone of laying hens (Ross Brown) under a low ambient temperature (6.9 °C). One hundred and twenty laying hens (46 weeks old) were divided into four groups, 30 hens per group. The laying hens were fed either a control diet containing 710.3 p.p.b. chromium or the control diet supplemented with 100, 200 or 400 μg chromium/kg diet. Increasing supplemental chromium increased live weight change (p ≤ 0.001, linear) and egg production (p ≤ 0.001, linear) and also improved feed efficiency linearly (p ≤ 0.001). Live weight change and egg production also had quadratic responses (p ≤ 0.001) to increasing chromium supplementation. Plasma insulin concentration increased linearly (p ≤ 0.001), whereas corticosterone concentration decreased linearly (p ≤ 0.001) as dietary chromium supplementation increased. The results of this study indicate that supplemental dietary chromium, 200 p.p.b. in particular, had a positive effect on performance and increased the plasma insulin concentration of laying hens under cold stress.     

Improving certain properties of wool fibers by applying chitosan nanoparticles and atmospheric plasma treatment

The nanochitosan particles were prepared by ionic gelation method using sodium tripolyphosphate (TPP) as anionic chemical agent. Structural and morphological properties of the nanoparticles were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) analyses. The results showed that nanoparticles were spherical with a diameter range of 17-105 nm. After nanochitosan synthesis, the effects of chitosan and nanochitosan concentrations on the dyeability, fastness properties, shrink-proofing, tensile strengths, and surface friction coefficients of untreated and plasma treated wool fabrics were investigated. The studies revealed that nanochitosan treated wool fabric possesses better dyeing and shrink-proofing properties in comparison with conventional chitosan treated fabrics.