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Various herbal coffee varieties are consumed traditionally in Turkey. In the current study, the ethanol extracts of the coffee and seed samples obtained from Gundelia tournefortii (tumble thistle), Nigella sativa (black cumin), Phoenix dactylifera (date), and Ceratonia siliqua (carob) as well as a sample of instant coffee (Nescafe®, green blend) were tested against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase, the enzymes connected to neurodegeneration. Since oxidative stress is strongly associated with neurodegeneration, antioxidant activity of the extracts was also determined. Antioxidant activity of the extracts was measured using anti-radical and metal-related methods. Total phenol and flavonoid contents were calculated using Folin–Ciocalteau's and AlCl3 reagents, respectively. Fatty acid compositions of the seed oils of tumble thistle and black seed were analyzed by GC–MS. Our results showed that the date sample exerted the highest AChE and BChE inhibition at 300 μg mL? 1 (52.96% and 83.22%, respectively).  相似文献   
103.
Based on the application of OB considerations (Part I) to various major thermal barrier coating (TBC) compositions and two types of important calcium–magnesium–alumino–silicates (CMAS)—desert sand and fly ash—the 2ZrO2·Y2O3 solid solution (ss) TBC composition, with high CMAS‐resistance potential, is chosen for studying molten‐CMAS/TBC interactions. It is demonstrated that 2ZrO2·Y2O3(ss) air plasma sprayed (APS) TBCs are highly resistant to high‐temperature attack by both sand‐CMAS and fly‐ash‐CMAS. Despite the differences in the compositions of the two CMASs, the overall CMAS‐attack mitigation mechanisms in both cases appear to be similar, viz reaction between 2ZrO2·Y2O3(ss) APS TBC and the CMAS, and the formation of main reaction products of Y‐depleted c‐ZrO2 and nonstoichiometric Ca–Y apatite. Large differences in the OBs (ΔΛ) between the 2ZrO2·Y2O3(ss) and the CMASs are good predictors of ready reaction between this TBC and these CMASs. While the details of the CMAS‐mitigation mechanisms can depend critically on various other aspects, the OB difference (ΔΛ) calculations could be used for the initial screening of CMAS‐resistant TBC compositions.  相似文献   
104.
The effects of various gum types [hydroxypropylmethylcellulose (HPMC), guar gum, xanthan gum, gum arabic] on the quality of deep‐fat fried chicken nuggets were studied. Chicken samples, 0.04 m in diameter and 0.015 m in thickness taken from the breast portion, were coated with batters composed of a 3:5 solid to water ratio by immersion. The solid content of batter formulations contained equal amounts of corn and wheat flours, 1.0% gum, 1.0% salt and 0.5% leavening agent. As control, batter without gum addition was used. Samples were fried at 180 °C for 3, 6, 9 and 12 min. The hardness and oil content of the chicken nuggets increased whereas the moisture content decreased during frying. HPMC and xanthan gums reduced oil absorption significantly compared with other gums and the control. When gum arabic was added to the batter formulation, a product with the highest oil content and porosity was obtained. Copyright © 2005 Society of Chemical Industry  相似文献   
105.
The peroxidation of linoleic acid (LA) in the absence and presence of either Cu(II) ions alone or Cu(II)‐ascorbate combination was investigated in aerated and incubated emulsions at 37°C and pH 7. LA peroxidation induced by either copper(II) or copper(II)‐ascorbic acid system followed pseudo‐first order kinetics with respect to primary (hydroperoxides) and secondary (aldehydes‐ and ketones‐like) oxidation products, detected by ferric‐thiocyanate and TBARS tests, respectively. α‐Tocopherol showed both antioxidant and prooxidant effects depending on concentration and also on the simultaneous presence of Cu(II) and ascorbate. Copper(II)‐ascorbate combinations generally led to distinct antioxidant behavior at low concentrations of α‐tocopherol and slight prooxidant behavior at high concentrations of α‐tocopherol, probably associated with the recycling of tocopherol by ascorbate through reaction with tocopheroxyl radical, while the scavenging effect of α‐tocopherol on lipid peroxidation was maintained as long as ascorbate was present. On the other hand, in Cu(II) solutions without ascorbate, the antioxidant behavior of tocopherol required higher concentrations of this compound because there was no ascorbate to regenerate it. Practical applications: Linoleic acid (LA) peroxidation induced by either copper(II) or copper(II)‐ascorbic acid system followed pseudo‐first order kinetics with respect to primary (hydroperoxides) and secondary (e.g., aldehydes and ketones) oxidation products. α‐Tocopherol showed both antioxidant and prooxidant effects depending on concentration and also on the simultaneous presence of Cu(II) and ascorbate. The findings of this study are believed to be useful to better understand the actual role of α‐tocopherol in the preservation of heterogenous food samples such as lipid emulsions. Since α‐tocopherol (vitamin E) is considered to be physiologically the most important lipid‐soluble chain‐breaking antioxidant of human cell membranes, the results can be extended to in vivo protection of lipid oxidation.  相似文献   
106.
The aim of this paper is to find a better alternative for the insulation of industrial noise and to improve the mechanical properties of fibre reinforced mud bricks. It was observed that the fibre reinforced mud bricks fulfill the compressive strength and sound insulation requirements of the ASTM and Turkish Standards. Basaltic pumice as an ingredient was found to improve the sound insulation performance of fibre reinforced mud bricks. The experimental results showed that fibre reinforced mud brick, with basaltic pumice as ingredient, can be used in industrial buildings for walls to improve sound insulation.  相似文献   
107.
2,4‐Dichlorophenoxyl acetic acid (2,4‐D) and glyphosate are used extensively as a herbicide in vicinity of Antalya, Turkey. Laboratory batch experiments were conducted to investigate the sorption isotherm and sorption‐desorption characteristics of 2,4‐D and glyphosate. Results indicated that degree of sorption of glyphosate was approximately 50 times higher than 2,4‐D (Kd= 34.43 vs. 0.66 L/Kg). The sorption of 2,4‐D and glyphosate was described by linear and rate‐limited processes for soil. Organic carbon content was most likely responsible for sorption behaviour of 2,4‐D and glyphosate. The rapid desorption can be attributed to soft carbon fraction (humic/fluvic acid and lipids) whereas slower desorption can be responsible by hard carbon fraction (black carbon, kerogen) of soils that led to chemically nonideal behaviour (hysteresis). Sorption of 2,4‐D was low due to most likely deactivation of organic carbon surfaces by excess carbonate fraction, whereas strong binding of glyphosate onto organic carbon causing high sorption behaviour.  相似文献   
108.
Earthquake induced deformation of earth dams   总被引:2,自引:1,他引:1  
The paper summarizes the different modes of failure affecting earth dams as a consequence of earthquake shaking. A case study is presented to illustrate seismic deformation analysis using the Alibey Earth Dam, Istanbul, Turkey as an example. The dynamic behaviour, failure modes and mechanisms of failure of the dam under possible ground motions were investigated. The results from finite element analysis are compared with the experimental study.   相似文献   
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