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11.
12.
The purpose of this study was to evaluate the knowledge, attitudes and practices among food service staff with regards to food hygiene in hospitals in Edirne, Turkey, and to provide baseline data for implementing HACCP in hospital food services by carrying out a questionnaire by a face-to-face interview. The current study shows that food service staff in Edirne hospitals have insufficient knowledge regarding the basics of food hygiene. And also revealed a discrepancy between attitudes and practices towards food hygiene. There is an immediate need for continuous training among food handlers regarding safe food handling practices. 相似文献
13.
In this study various two-stage processes were investigated for biological hydrogen production from olive mill wastewater (OMW) by Rhodobacter sphaeroides O.U.001. Two-stage processes consist of physicochemical pretreatment of OMW followed by photofermentation for hydrogen production. Explored pretreatment methods were chemical oxidation with ozone and Fenton's reagent, photodegradation by UV radiation, and adsorption with clay or zeolite. Among these different two-stage processes, strong chemical oxidants like ozone and Fenton's reagent have the highest color removal (90%). However, their effluents were observed to be unsuitable for both hydrogen production and bacterial growth. On the other hand, clay treatment method was selected as the optimum process that allows fast and low-cost treatment as well as its effluent found to have the highest hydrogen production potential (31.5 m3 m?3). Spent-clay regeneration was also investigated on the grounds that solid waste minimization is important for the overall efficiency of this process. 相似文献
14.
The efficiency of ultraviolet/hydrogen peroxide photo‐oxidation processing for enhancing the biodegradability of Reactive Black 5 prior to biological treatment processing of acclimated and non‐acclimated sequencing batch reactors was evaluated. Photo‐oxidation experiments were conducted according to an experimental design method in which aqueous Reactive Black 5 samples with an initial concentration of 200 mg/l were exposed to ultraviolet irradiation for 15, 30 and 60 min in the presence of various concentrations of hydrogen peroxide (250, 500 and 1000 mg/l) at pH 7. Pretreated samples were then subjected to respirometric biodegradability tests using the sludge cultures obtained from acclimated and non‐acclimated sequencing batch reactors for the determination of the kinetic constants of qmax and Ks according to the modified Organisation of Economic Cooperation and Development 209 method. Calculated values of qmax and Ks showed that the acclimated sludge of the sequencing batch reactor showed a better performance than the non‐acclimated sludge in the degradation of photochemically pretreated aqueous Reactive Black 5. The advantage of acclimated sludge compared with non‐acclimated sludge for the biodegradation of Reactive Black 5 diminished when photochemical pretreatment conditions reached higher levels in terms of oxidation time and hydrogen peroxide concentration. 相似文献
15.
Sükran Cakli Latif Taskaya Duygu Kisla Ufuk Çelik Can Altinel Ataman Asli Cadun Berna Kilinc Ramin Haji Maleki 《European Food Research and Technology》2005,220(5-6):526-530
Abstract Production of fish fingers was achieved by using fish species such as sardine (Sardina pilchardus, Walbaum, 1792), whiting (Merlangius merlangus, Linnaeus, 1758) and pike perch (Sander lucioperca, Linnaeus, 1758). Quality changes of battered fish patties during a period of 8 months at –18 °C were investigated. According to the results of microbiological and chemical analysis, fish fingers were found to be within acceptable limits during frozen storage for 8 months. However, sensory analysis showed that, at the end of the frozen storage, fish fingers made from sardine could not be consumed because of rancidity. 相似文献
16.
Ahmed Kabouche Zahia Kabouche Mehmet Öztürk Ufuk Kolak Gülaçtı Topçu 《Food chemistry》2007,102(4):1281-1287
The root extract of endemic Algerian Salvia species Salvia barrelieri Ettling and its diterpenoids were investigated for potential antioxidant activity. From its acetone extract, a new natural abietane diterpenoid 7-oxoroyleanone-12-methyl ether (1) and six known diterpenoids 7α-acetoxyroyleanone-12-methyl ether (2), royleanone (3), horminone (4), 7-acetylhorminone (5), cryptojaponol (6) and inuroyleanol (7) were isolated, and their structures were elucidated by spectroscopic means. Among the diterpenoids, the new diterpenoid 7-oxoroyleanone-12-methyl ether (1) showed highest superoxide anion scavenging activity while inuroyleanol (7) showed both the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity and inhibition of lipid peroxidation in β-carotene–linoleic acid system. These findings indicate that S. barrelieri extract as well as isolated abietane diterpenes, particularly inuroyleanol are promising antioxidants which can be used as food additives. 相似文献
17.
Ufuk Yildiz Ignác Capek Dušan Berek Yanko Sarov Ivo W Rangelow 《Polymer International》2007,56(3):364-370
The inverse microemulsion copolymerization of acrylamide and butyl acrylate initiated by ammonium peroxodisulphate, a water‐soluble initiator, and stabilized by anionic emulsifiers sodium bis‐2‐ethylhexylsulfosuccinate and sodium dodecylsulphate (SDS) has been studied. An increase of SDS concentration was observed to increase both the rate of polymerization and the particle size. The average number of radicals per particle (n?) is much below 0.5, which indicates desorption of monomeric radicals from polymer particles. The exit (desorption) rate constants k′des (cm2 s?1) and kdes (s?1) were evaluated as a function of SDS concentration (or the particle size) according to the Ugelstad/O'Toole (I), Nomura (II) and Gilbert (III) models. The value of kdes (s?1) decreases with increasing particle size (or SDS concentration) for all three (I, II and III) models. A complex trend appears for k′des (cm2 s?1): the Ugelstad/O'Toole model estimates a decrease, the Nomura model finds no variation and the Gilbert model estimates even a slight increase in k′des with increasing SDS concentration. Copyright © 2006 Society of Chemical Industry 相似文献
18.
Ufuk G Erdal Zeynep K Erdal Glen T Daigger Clifford W Randall 《Water science and technology》2008,58(6):1329-1334
Reduced EBPR performance in full and bench-scale EBPR studies was linked to the proliferation of GAOs but often time with the lack of any evidence. In this study, a detailed enzymatic study was coupled with batch tests and electron microscopy results for a realistic explanation. The results eliminated the possibility of population shift from PAO to GAO or other non-PAO due to the short batch test period provided which would not allow a population shift and further justified with the electron microscopy results. The results indicate that glycogen serves not only as source of reducing power for PHA production but also serves as an alternative energy source when the poly-P pool of the PAOs is depleted. Slow generation of ATP via glycolytic pathway at 5 degrees C cannot satisfy energy requirements of EBPR cells to complete several cell functions including acetate uptake and PHA storage. However, the glycolytic pathway is efficiently operable at warm temperatures (> 20 degrees C). The reduced performance of enhanced EBPR facilities operated at warm temperature may not be a result of GAO proliferation; instead it may be related the efficient use of the glycolytic pathway by PAOs which results in more glycogen storage and less P uptake, thereby reducing the EBPR performance. 相似文献
19.
Harun Koku nci Ero
lu Ufuk Gündüz Meral Yücel Lemi Türker 《International Journal of Hydrogen Energy》2002,27(11-12)
Photosynthetic bacteria are favorable candidates for biological hydrogen production due to their high conversion efficiency and versatility in the substrates they can utilize. For large-scale hydrogen production, an integrated view of the overall metabolism is necessary in order to interpret results properly and facilitate experimental design. In this study, a summary of the hydrogen production metabolism of the photosynthetic purple non-sulfur (PNS) bacteria will be presented.Practically all hydrogen production by PNS bacteria occurs under a photoheterotrophic mode of metabolism. Yet results show that under certain conditions, alternative modes of metabolism—e.g. fermentation under light deficiency—are also possible and should be considered in experimental design.Two enzymes are especially critical for hydrogen production. Nitrogenase promotes hydrogen production and uptake hydrogenase consumes hydrogen.Though a wide variety of substrates can be used for growth, only a portion of these is suitable for hydrogen production. The efficiency of a certain substrate depends on factors such as the activity of the TCA cycle, the carbon-to-nitrogen ratio, the reduction-state of that material and the conversion potential of the substrate into alternative metabolites such as PHB.All these individual components of the hydrogen production interact and are subject to strict regulatory controls. An overall scheme for the hydrogen production metabolism is presented. 相似文献
20.
The Cape Hatteras Lighthouse is the tallest brick structure of its kind in the United States. The national icon was closed to visitors after several pieces of the cast iron stairs, original to the structure, dislodged and fell inside the lighthouse. This finding led to the investigative efforts outlined in this paper, on the load carrying capacity of the stairs. This article summarizes the engineering effort in the condition assessment of the stairs, the review of visitor statistical data for likely load exposures during peak times, and the development of a unique load test program for the stairs of the historic structure. The load testing program was unique because of the physical constraints of the lighthouse shaft as well as the dimensions of the stair treads. In addition, the engineering team had the added objective of protecting the integrity of the national icon and performing the load test without exposing the historic stairs to an unnecessary risk of failure. 相似文献