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991.
Nuray Erkan Özkan Özden Didem Üçok Alakavuk Ş. Yasemin Yildirim Müge İnuğur 《European Food Research and Technology》2006,222(5-6):667-673
The effect of modified atmosphere packing (MAP) (O2/CO2/N2, 5/35/60 (%) and O2/CO2/N2, 5/70/25 (%)) on the quality of sardine stored in refrigerator was investigated in terms of sensory, chemical and microbiological
analysis. Although chemical and microbiological analyses indicated that modified atmosphere packing prolonged the shelf life
of sardine compared with that of air packing, sensory analysis showed that the extension of shelf life was (condition: O2/CO2/N2, 5/70/25 (%)) 8 days and in air (condition: O2/CO2/ N2, 5/35/60 (%)) 6 days. The results showed significant differences (p <0.05) between air and MAP storage conditions. 相似文献
992.
In this work, the stress analysis of isotropic and ortotropic laminae both with a hole and without a hole and laminated both with a hole and without a hole composite plates have been examined using the finite element method. In order to solve the problem, a computer program has been written by using characteristics of eight-node isoparametric plane element. The calculations have been tested on various composite and steel materials by this program. The results have been shown in diagrams and tables and compared with literature. It was observed that the stress distributions in the plate with a hole was totally different from the plate without a hole. The analyses have showed that, the elastic stresses have been gradually reduced as moving from the first layer to the second. 相似文献
993.
Summary Side chain thioxanthone-containing polymer (PSt-TX) was synthesized and characterized by modification of polystyrene prepared
by Atom Transfer Radical Polymerization. PSt-TX exhibits absorption characteristics similar to that of the unsubstitued thioxanthone.
Its capability to act as initiator for the polymerization of methyl methacrylate was also examined. 相似文献
994.
Samples in the system PbOPbF2Nb2O5NbO2F prepared at 875 K and 1025 K were studied by X-ray single crystal and powder diffraction as well as electron diffraction methods. Six new compounds were characterized as Pb0.74Nb10.62(O,F)30 (orth.), Pb1.36Nb10.91(O,F)30 (tetr.), Pb0.27Nb(O,F.)3.17 (hex.), Pb2Nb3O7F5 (tetr.), Pb0.75NbO3F0.5 (tetr.) and Pb1?Nb(O,F)2+ (cub.) 相似文献
995.
996.
Seasonal variations in the amino acid and fatty acid compositions of wild sea bass (Dicentrarchus labrax) captured in the north eastern Mediterranean were investigated. In all seasons, the major amino acids in sea bass fillets
were determined to be aspartic acid, glutamic acid and lysine. Methionine, tyrosine and histidine composition of the fillets
were lower than those of the other amino acids in all seasons. The ratios of essential (E, g amino acid/16 g N)/nonessential
(NE, g amino acid/16 g N) amino acids were observed to be 0.75 for winter, 0.76 for autumn, 0.77 for both spring and summer.
Results showed that, sea bass fillets are well-balanced food source in terms of E/NE ratios in all seasons. In addition, seasonal
differences in polyunsaturated fatty acid (PUFA) composition of the fillets were observed in all seasons. The major fatty
acids of sea bass fillets were observed to be palmitic acid (16:0), oleic acid (18:1ω9), eicosapentaenoic acid (EPA, 20:5ω3)
and docosahexaenoic acid (DHA, 22:6ω3). The amounts of EPA+DHA in autumn, winter, spring and summer were determined as 0.16,
0.12, 1.14 and 1.02 g/100 g wet weight, respectively. 相似文献
997.
In this work, one ternary Al–40Zn–3Cu and seven quaternary Al–40Zn–3Cu–(0.25–5)Si alloys were synthesized by permanent mould
casting. Their microstructure, mechanical and lubricated wear properties were investigated using appropriate test apparatus
and techniques. As the silicon content increased the hardness of the alloys increased, but their elongation to fracture decreased.
Tensile strength of the alloys decreased with increasing silicon content following a sharp decrease and a slight increase.
Among the silicon-containing quaternary alloys the highest and the lowest tensile strength values (348 and 305 MPa) were obtained
with the Al–40Zn–3Cu–2Si and Al–40Zn–3Cu–5Si alloys, respectively, while the base alloy (Al–40Zn–3Cu) exhibited a tensile
strength of 390 MPa. However, the volume loss due to wear of the alloys increased with increasing silicon content after showing
an initial increase and a sharp decrease. The lowest wear loss was obtained with the alloy containing approximately 2% Si
which has the highest tensile strength among the quaternary alloys containing more than 0.25% Si. Wear surfaces of the alloys
were characterized mainly by smearing indicating that adhesion is the dominant wear mechanism for the experimental alloys. 相似文献
998.
999.
Sulfated Hydrogel Matrices Direct Mitogenicity and Maintenance of Chondrocyte Phenotype through Activation of FGF Signaling 下载免费PDF全文
Ece Öztürk Øystein Arlov Seda Aksel Ling Li David M. Ornitz Gudmund Skjåk‐Bræk Marcy Zenobi‐Wong 《Advanced functional materials》2016,26(21):3649-3662
Deciphering the roles of chemical and physical features of the extracellular matrix (ECM) is vital for developing biomimetic materials with desired cellular responses in regenerative medicine. Here, it is demonstrated that sulfation of biopolymers, mimicking the proteoglycans in native tissues, induces mitogenicity, chondrogenic phenotype, and suppresses catabolic activity of chondrocytes, a cell type that resides in a highly sulfated tissue. Through tunable modification of alginate it is shown that increased sulfation of the microenvironment promotes fibroblast growth factor (FGF) signaling‐mediated proliferation of chondrocytes in a 3D matrix independent of stiffness, swelling, and porosity. Furthermore, for the first time it is shown that a biomimetic hydrogel acts as a 3D signaling matrix to mediate a heparan sulfate/heparin‐like interaction between FGF and its receptor leading to signaling cascades inducing cell proliferation, cartilage matrix production, and suppression of dedifferentiation markers. Collectively, this study reveals important insights on mimicking the ECM to guide self‐renewal of cells via manipulation of distinct signaling mechanisms. 相似文献
1000.
In this study, the CuAl–TiC composite materials were produced using hot pressing process. Effect of TiC grain size (0.2, 4 and 20 μm) on some properties of these materials was investigated experimentally. Production of CuAl–TiC composites was carried out under pressure of 35 MPa, at 700°C, and for a sintering time of 5 minutes. SEM-MAP studies showed that the TiC grains were relatively homogeneously distributed in the CuAl matrix. Microstructure analysis revealed that the composite materials consist of Cu, Al, Cu9Al4, CuAl2 and TiC phases. With the decreasing of TiC grain size, the hardness, transverse rupture strength, relative density and sintered density of composites increased. 相似文献