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991.
Ali Gücükoğlu Özgür Çadirci Göknur Terzi T. Onur Kevenk Mustafa Alişarli 《Journal of food science》2013,78(5):M738-M741
The aim of this study was to determine the prevalence of enterotoxigenic and methicillin‐resistant Staphylococcus aureus in ice creams. After culture‐based identification of isolates, the presence of 16S rRNA and nuc was confirmed by mPCR. S. aureus was identified in 18 of 56 fruity (32.1%), 4 of 32 vanilla (12.5%), and 1 of 12 chocolate (8.3%) ice creams. S. aureus was identified as 38 isolates in 23 ice cream samples by culture‐based techniques, but only 35 isolates were confirmed by PCR as S. aureus. To determine the enterotoxigenic properties of PCR‐confirmed S. aureus isolates, a toxin detection kit was used (SET RPLA®). Of the 12 enterotoxigenic S. aureus isolates, 9 SEB (75%), 1 SED (8.3%), 1 SEB+SED (8.3%), and 1 SEA+SEB+SED (8.3%) expressing isolates were found. The presence of enterotoxin genes (sea, seb, sed) was identified in 13 (37.1%) out of 35 isolates by the mPCR technique. In the ice cream isolates, the sea, seb, and sed genes were detected: 1 sea (7.6%), 9 seb (69.2%), 1 sed (7.6%), 1 seb+sed (7.6%), and 1 sea+seb+sed (7.6%), respectively. The sec gene was not detected in any of these isolates. One of the 35 (2.8%) S. aureus strain was mecA positive. 相似文献
992.
This study examines the effect of the particle size of fluorocarbon‐based water‐oil‐soil‐repellent finishing agents on color fastness and colorimetric properties by experimental analyses. Therefore, two finishing agents with different particle sizes were applied to red‐dyed and blue‐dyed knitted fabric samples of single jersey and rib‐structured knits, produced from 100% cotton yarns. The results show that smaller particle size causes less color change for all washings (0, 1 and 5), both of the dyes and the fabric structures (single jersey and rib). Also, it is observed that smaller particle size positively affects the rub fastness results. 相似文献
993.
Emin Çadırlı 《Metals and Materials International》2013,19(3):411-422
Al(100?x)-Cux alloys (x=3 wt%, 6 wt%, 15 wt%, 24 wt% and 33 wt%) were prepared using metals of 99.99% high purity in vacuum atmosphere. These alloys were directionally solidified under steady-state conditions by using a Bridgman-type directional solidification furnace. Solidification parameters (G, V and ), microstructure parameters (λ1, λ2 and λE) and mechanical properties (HV, σ) of the Al-Cu alloys were measured. Microstructure parameters were expressed as functions of solidification parameters by using a linear regression analysis. The dependency of HV, σ on the cooling rate, microstructure parameters and composition were determined. According to experimental results, the microhardness and ultimate tensile strength of the solidified samples was increased by increasing the cooling rate and Cu content, but decreased with increasing microstructure parameters. The microscopic fracture surfaces of the different samples were observed using scanning electron microscopy. Fractographic analysis of the tensile fracture surfaces showed that the type of fracture significantly changed from ductile to brittle depending on the composition. 相似文献
994.
Direct Solar Floor Heating ( DSFH) is an original solar heating system made of a set of water circulation pipes embedded in a concrete floor which is directly connected to the solar collectors without heat exchanger or any other storage. The concrete slab is thick enough to be used as storage. Performance of many installations in France have been measured and give satisfaction. Furthermore, a simplified sizing method has been proposed. We set forth simulations with EMGP2, in order to improve both of these results and to optimize the economic and technical performances of the system. An optimum size which the method did not anticipate is indeed found if we correctly took into account the function of the floor in the system. Two points have to be supervised: comfort and regulation for which some preliminary informations are given. A methodology is proposed in order to analyse bare results from measured data. 相似文献
995.
Hasan Ferdi Gerçel Gürsoy Çayir Özgül Gerçel 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2013,35(7):611-618
Apricot stone (Prunus armeniaca L.) was pyrolyzed in a directly heated fixed-bed reactor under nitrogen atmosphere. Effects of sweeping gas flow rates and pyrolysis temperature on the pyrolysis of the biomass were also studied. Pyrolysis runs were performed using reactor temperatures between 400°C and 700°C with heating rate of about 300°C min?1. As the pyrolysis temperature was increased, the percentage mass of char decreased while gas product increased. The product yields were significantly influenced by the process conditions. The bio-oil obtained at 550°C, at which the liquid product yield was maximum, was analyzed. It was characterized by Fourier transform infrared spectroscopy (FT-IR). In addition, the solid and liquid products were analyzed to determine their elemental composition and calorific value. Chemical fractionation of bio-oil showed that only low quantities of hydrocarbons were present, while oxygenated and polar fractions dominated. 相似文献
996.
In this paper, a simulated annealing approach is developed for the parallel mixed-model assembly line balancing and model sequencing (PMMAL/BS) problem which is an extension of the parallel assembly line balancing (PALB) problem introduced by Gökçen et al. (2006). In PALB, the aim is to balance more than one assembly line together. Balancing of the lines simultaneously with a common resource is very important in terms of resource minimisation. The proposed approach maximises the line efficiency and distributes the workloads smoothly across stations. The proposed approach is illustrated with two numerical examples and its performance is tested on a set of test problems. The computational results show that the proposed approach is very effective for PMMAL/BS. 相似文献
997.
The prosperity of a firm depends highly on the functional integration of its various departments, and in particular the cooperation between the production and the marketing departments appears to have a large impact on the well-being of a firm. The aim of this study is to model an aggregate production planning problem that considers the production and marketing functions in a simultaneous manner. The developed multi-period, multi-product model with the objective of profit maximization reflects the characteristics of both departments. Demand for each product in each period is generated through the use of demand functions. The advertising efficiency and price of the products are determined within the model. The cash outflow for advertising expenditures is approximated by a quadratic cost function, and the production cost exhibits economies of scale. Also, stockouts are taken into consideration in the form of backlogging. A solution methodology consisting of two phases is developed, and cases displaying some important characteristics are generated and solved in order to test the performance of the proposed model. This methodology incorporates linear mixed integer programming which is embedded in two different search techniques, along with a dynamic programming-based heuristic procedure. 相似文献
998.
Previous research has reported that the decision criteria used to evaluate suppliers differ by product category. This paper presents a framework for defining the supplier selection criteria by investigating possible quantitative and qualitative criteria reported by earlier studies according to the levels of buyer–supplier relationship, the company's competitive situation and its corporate strategies, rather than investigating these criteria in respect of product category. The solution proposed in this study not only assists decision makers to define selection criteria, but also supports determining the buyer–supplier integration level. An actual case in Audio Electronics, a Turkish electronics business, demonstrates the feasibility of applying the proposed framework in practice. 相似文献
999.
It is apparent that there is a need for integrated criteria in the performance measurement of modern organisations when dealing with the performance measurement of manufacturing businesses. This paper addresses this issue in the context of measuring the performance of the 2nd Air Supply and Maintenance Center Command manufacturing/maintenance jobshops of Turkey by using a new framework which combines fuzzy TOPSIS (technique for order preference by similarity to ideal solution) for measuring qualitative performance with DEA (data envelopment analysis) for measuring quantitative performance. This proposed approach provides a comprehensive measure of performance incorporating both quantitative and qualitative attributes, which in general reflect efficiency and effectiveness of the manufacturing jobshops respectively. 相似文献
1000.
钠硼解石含有大量的结晶水。采用煅烧法可以将固体组分中的一部水脱去,得到一种多孔结构物质,以提高浸出反应速率。采用醋酸铵作为浸出溶剂,研究煅烧钠硼解石样品在不同温度下的溶解情况。研究了反应参数对煅烧钠硼解石溶解的影响。研究发现,煅烧样品的溶解速率高于未煅烧样品的溶解速率。在煅烧温度低于150℃时,煅烧钠硼解石的溶解速率随着煅烧温度的升高而加快。钠硼解石的浸出反应速率符合化学反应控制模型。溶解过程中的活化能为41.5kJ/mol。 相似文献