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51.
对于短纤纱来说,纱线不匀是不可避免的,主要是因为天然纤维的变异、纺纱方法以及纤维在纱中的排列;但对于长丝纱来说,异状粒子、纺纱过程的不规则、纱线冷却过程和卷绕过程的操作、机器的缺陷和牵伸问题会很快导 相似文献
52.
M. Yakup Arica Serap enel N. Gürdal Alaeddinolu Süleyman Patir Adil Denizli 《应用聚合物科学杂志》2000,75(14):1685-1692
Microporous poly(2‐hydroxyethyl methacrylate) (pHEMA) membrane was prepared by UV‐initiated photopolymerization. The spacer arm (i.e., hexamethylene diamine) was attached covalently and then invertase was immobilized by the condensation reaction of the amino groups of the spacer arm with carboxyl groups of the enzyme in the presence of carbodiimides. The values of the Michael's constant Km of invertase were significantly larger (ca. 2.5 times) upon immobilization, indicating decreased affinity by the enzyme for its substrate, whereas Vmax was smaller for the immobilized invertase. Immobilization improved the pH stability of the enzyme as well as its temperature stability. Thermal stability was found to increase with immobilization and at 70°C the half times for the activity decay were 12 min for the free enzyme and 41 min for the immobilized enzyme. The immobilized enzyme activity was found to be quite stable in repeated experiments. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 1685–1692, 2000 相似文献
53.
Viability and activity of bifidobacteria in yoghurt containing fructooligosaccharide during refrigerated storage 总被引:1,自引:0,他引:1
Aye Sibel Akaln Serap Fenderya & Necati Akbulut 《International Journal of Food Science & Technology》2004,39(6):613-621
The viability of yoghurt bacteria and two commercial strains of bifidobacteria was assessed in either yoghurt containing chicory fructooligosaccharide (FOS) or without any prebiotic, during 28 days storage at 4 °C. All the products showed a decrease in the viable count of yoghurt bacteria and bifidobacteria during storage. Numbers of Lactobacillus delbrueckii ssp. bulgaricus decreased faster than those for Streptococcus thermophilus. The viability of bifidobacteria in yoghurt was affected by the strain type and the presence of FOS. Bifidobacterium animalis exhibited better stability in the yoghurt than B. longum. The recommended level of 1 million cells was exceeded for B. animalis throughout storage. The highest viable number of bifidobacteria (3.59–2.25 × 107 CFU g?1) was obtained in the product containing B. animalis and FOS. Viability of B. longum in yoghurt containing FOS remained above 106 CFU g?1 for up to 21 days, whereas this level was maintained for only 7 days for that organism in yoghurt without any prebiotic. 相似文献
54.
Serap Saglk Mustafa Alpaslan Tuncay Gezgin Kartal etintürkc Adem Tekinay Kasm Cemal Güven 《European Journal of Lipid Science and Technology》2003,105(2):104-107
Total lipid content and fatty acid composition were determined for wild and cultivated gilthead seabream and sea bass. Fatty acid analyses were carried out by gas chromatography‐ mass spectrometry. Respective total lipid content of flesh in cultivated gilthead seabream and sea bass were 1.7‐5.0‐times those of wild samples. Palmitic acid (C16:0) and oleic acid (C18:1n‐9) were the major fatty acids respectively among the saturated fatty acids and monounsaturated fatty acids of each fish species. It is noteworthy that both linoleic acid (C18:2n‐6) and arachidonic acid (C20:4n‐6) were predominant in total n‐6 polyunsaturated fatty acids in the respective cultivated and wild types. Eicosapentaenoic acid (C20:5n‐3) and docosahexaenoic acid (C22:6n‐3) amounts were significantly higher in flesh of cultivated fish than in wild fish. 相似文献
55.
Yamanoglu Ridvan Bahador Abdollah Kondoh Katsuyoshi Gumus Serap Gokce Sinan Muratal Onur 《Powder Metallurgy and Metal Ceramics》2021,60(3-4):216-224
Powder Metallurgy and Metal Ceramics - Although magnesium is one of the materials with the lowest density, its application is limited amongst other commercial materials due to insufficient... 相似文献
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Ozgun Cirakman Bilge Gunsel Neslihan Serap Sengor Sezer Kutluk 《Multimedia Tools and Applications》2014,71(3):1381-1409
We propose a video copy detection scheme that employs a transform domain global video fingerprinting method. Video fingerprinting has been performed by the subspace learning based on nonnegative matrix factorization (NMF). It is shown that the binary video fingerprints extracted from the basis and gain matrices of the NMF representation enable us to efficiently represent the spatial and temporal content of a video segment respectively. An extensive performance evaluation has been carried out on the query and reference dataset of CBCD task of TRECVID 2011. Our results are compared with the average and the best performance reported for the task. Also NDCR and F1 rates are reported in comparison to the performance achieved via the global methods designed by the TRECVID 2011 participants. Results demonstrate that the proposed method achieves higher correct detection rates with good localization capability for the transformation of text/logo insertion, strong re-encoding, frame dropping, noise addition, gamma change or their mixtures; however there is still potential for improvement to detect copies with picture-in-picture transformations. It is also concluded that the introduced binary fingerprinting scheme is superior to the existing transform based methods in terms of the compactness. 相似文献
59.
In this study, we investigate the relationship between income and environmental quality for Turkey at two levels. First, the relationship between the CO2 emissions and per capita income is examined by the help of a time series model using cointegration techniques. In the second stage, the relationship between income and air pollution is investigated by using PM10 and SO2 measurements in Turkish provinces. In this part of the study panel data estimation techniques are utilized. The time series model covers 1968–2003, and the panel data model covers 1992–2001 including observations from 58 provinces. A monotonically increasing relationship between CO2 and income is found in the long-run according to time series analysis. On the other hand, panel data analysis indicates an N-shape relationship for SO2 and PM10 emissions. Therefore, the results of our time series and panel data analyses do not support the Environmental Kuznets Curve hypothesis, which assumes an inverted U-shaped relationship between environmental degradation and income. 相似文献
60.
AbstractIn underwater optical communication links, bit error rate (BER) is an important performance criterion. For this purpose, the effects of oceanic turbulence on multimode laser beam incidences are studied and compared in terms of average BER (<BER>), which is related to the scintillation index. Based on the log-normal distribution, <BER> is analysed for underwater turbulence parameters, including the rate of dissipation of the mean squared temperature, the rate of dissipation of the turbulent kinetic energy, the parameter that determines the relative strength of temperature and salinity in driving index fluctuations, the Kolmogorov microscale length and other link parameters such as link length, wavelength and laser source size. It is shown that use of multimode improves the system performance of optical wireless communication systems operating in an underwater medium. For all the investigated multimode beams, decreasing link length, source size, the relative strength of temperature and salinity in driving the index fluctuations, the rate of dissipation of the mean squared temperature and Kolmogorov microscale length improve the <BER>. Moreover, lower <BER> values are obtained for the increasing wavelength of operation and the rate of dissipation of the turbulent kinetic energy in underwater turbulence. 相似文献