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排序方式: 共有6995条查询结果,搜索用时 15 毫秒
991.
Tiago Simões João Carvalho Ana Sousa Marco F.L. Lemos Maria M. Gil Rui Pedrosa Carla Tecelão 《Journal of food science》2013,78(5):C691-C695
Proximate composition (ash, moisture, total protein, and fat contents) and fatty acid profile of Balistes capriscus (grey triggerfish) were assessed over a 6‐months period (April to September, 2011) in animals captured along the coast of Peniche (Portugal). High protein (18.9% to 21.4%) and low lipid (0.5% to 0.8%) contents were determined. The highest lipid level was found in June‐captured animals. High proportions of n‐3 polyunsaturated fatty acids (n‐3 PUFA) were observed (53.87 ± 2.00%) together with substantial quantities of oleic acid (27.58 ± 1.09%) and palmitic acid (16.52 ± 0.93%). Docosahexaenoic acid accounted for 77% of the total PUFA and was 7 times more abundant than eicosapentaenoic acid, and the n‐3/n‐6 ratio was 7.2. Gender did not influence lipid levels and the fatty acid profile, but seasonal variations were observed for PUFA and monounsaturated fatty acid contents. Overall, the nutritional properties of this underexploited species may be comparable to those of other lean fish species with higher economic value. 相似文献
992.
993.
Study on the soldering in partial melting state (1) analysis of surface tension and wettability 总被引:2,自引:0,他引:2
Jae Yong Park Jun Seok Ha Choon Sik Kang Kyu Sik Shin Moon Il Kim Jae Pil Jung 《Journal of Electronic Materials》2000,29(10):1145-1152
This paper introduces the partial melting process for solder application and characterization of its feasibility using Pb-Sn,
Ag-Sn, Sn-Cu, Sn-In and Sn-Bi alloys. In order to show that the liquid phase in the semi-liquid state maintains the similar
wettability as the single-phase liquid, the wetting balance tests are conducted with varying temperatures and compositions.
The results are then compared with the surface tension of liquid, both measured and calculated, to examine the correlation.
The results from this investigation indicate that the partial melting can yield satisfactory solder joints as long as the
liquid phase acquires sufficient chemical activity. At a condition where the partial melting is effective, a direct correlation
between the wettability and the surface tension is found to exist. All alloys except two, Sn-Bi and Sn-In, are found to show
a reasonable wettability in semi-liquid state. 相似文献
994.
Hak Sung Kim Jin Sung Kang Jong Se Park H. Thomas Hahn Hyun Chul Jung Jae Woo Joung 《Composites Science and Technology》2009,69(7-8):1256-1264
Copper nano-ink with a drop-on-demand (DOD) piezoelectric inkjet printing method was introduced. The printed electrodes were thermally sintered to ensure high-quality electrical and mechanical performances. To check the reliability of the printed electrodes on a polymer layer, resistance changes were measured under static loading. The electrodes with various widths and thicknesses were used to find the optimal dimensions. A multifunctional composite laminate which can harvest and store a solar energy was fabricated using printed electrodes. An amorphous silicon solar cell and a thin film solid state lithium-ion battery were adhesively joined and electrically connected to a thin flexible printed circuit board (PCB). Then, the passive components such as resistor and diode were electrically connected to the printed circuit board by silver pasting. The integrated PCB was co-cured with a carbon/epoxy composite laminate by the vacuum bag molding process in an autoclave. The structural and functional performance of the final energy harvesting/storage composite laminate was tested under mechanical loading. 相似文献
995.
Effects of maleinated compatibilizer and heat treatment on the internal structure and physical properties of PP/organoclay nanocomposites were investigated by using various measurements, e.g., SAXS, TEM, DSC and DMTA, and rotational rheometer. Experimental results showed that maleination and heat treatment affected the internal structure and dynamic mechanical properties of PP/organoclay nanocomposites. Storage modulus and loss tangent of PP/organoclay nanocomposites were strongly related to the compatibilizer loadings and heat treatment conditions because the interfacial structure between PP molecular chains and organoclay particles had been changed by the addition of compatibilizer to PP/organoclay nanocomposites. DSC and DMTA results of the compatibilized nanocomposites and effects of heat treatment on crystallization and dynamic mechanical thermal properties demonstrated that there is a small change in the glass transition temperature because the chain mobility and free volume in the amorphous region are increased by heat treatment. It was found that heat treatment imposed influence on both amorphous and crystalline regions of PP/organoclay nanocomposites. 相似文献
996.
Symmetrical internal alkynes can be prepared either by diarylation of mono‐ and bis(trimethylsilyl)acetylene (TMSA and BTMSA) catalyzed by ligand‐less palladium(II) chloride or by a di(2‐pyridyl)methylamine‐derived palladium(II ) chloride complex 1 (typical 0.1–1 mol % of Pd loading) in water using pyrrolidine as base and tetra‐n‐butylammonium bromide as additive. Alternatively, this same process is performed in NMP in the presence of tetra‐n‐butylammonium acetate (TBAA) as base with even lower Pd loadings (0.001–1 mol % Pd). The same reaction conditions are applied to the synthesis of unsymmetrical internal alkynes by monoarylation of silylated terminal alkynes. Aryl iodides can be coupled with TMSA, BTMSA and silylated terminal alkynes under heating or at room temperature, whereas for aryl bromides couplings are performed under water reflux or at 110 °C in the case of NMP. Complex 1 can be reused during several cycles either in water or in NMP without loss of catalytic activity. These simple reaction conditions allow the preparation of internal alkynes without secondary products, most probably by succesive protiodesilylation‐Sonogashira coupling. 相似文献
997.
Heewon Kye Byeong‐Seok Shin Yeong Gil Shin Helen Hong 《Computer Animation and Virtual Worlds》2005,16(5):547-557
Shear–warp volume rendering has the advantages of a moderate image quality and a fast rendering speed. However, in the case of dynamic changes in the opacity transfer function, the efficiency of memory access drops, as the method cannot exploit pre‐classified volumes. In this paper, we propose an efficient algorithm that exploits the spatial locality of memory references for interactive classifications. The algorithm inserts a rotation matrix when factorizing the viewing transformation, so that it may perform a scanline‐based traversal in both object space and image space. In addition, we present solutions to some problems of the proposed method, namely inaccurate front‐to‐back composition, the occurrence of holes, and increased computation. Our method is noticeably faster than traditional shear‐warp rendering methods because of an improved utilization of cache memory. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
998.
C. Abalos A. Paul A. Mendoza E. Solano C. Palazon F. J. Gil 《Journal of Materials Engineering and Performance》2013,22(3):759-766
The aim of this study was to determine the influence of soft drinks on the surface of Ni-Ti archwires and their corrosion behavior. Archwires with different patterns (smooth, scratch, dimple, and crack) were selected and characterized by scanning electron microscopy and laser confocal microscopy. Immersion tests were performed in artificial saliva (pH 6.7) with a soft drink with a pH of 2.5 for 28 days. The results showed an increase in the surface defects and/or roughness of the dimple, crack and scratch patterns with the immersion times, and a decrease in corrosion resistance. A relationship between the surface pattern and the extent of the corrosion in Ni-Ti archwires with soft drinks at low pH has been demonstrated. Pattern should be taken into account in future studies, and manufacturing processes that produce surface defects (especially cracks) should be avoided. 相似文献
999.
1000.
M. Gil S. Estévez N. Kontoudakis F. Fort J. M. Canals F. Zamora 《European Food Research and Technology》2013,237(4):481-488
Two red wines with a very high ethanol content were partially dealcoholized by reverse osmosis, so that the influence of this technique on wine color, chemical composition and sensory quality could be studied. No statistically significant differences were found in pH, color intensity, total phenolic index, proanthocyanidin concentration and their mean degree of polymerization between control wines and partially dealcoholized wines (?1 and ?2 vol. %). Some slight but significant differences were found in titratable acidity, anthocyanins, CIELab coordinates and polysaccharides. However, these differences were really quite small and only significant in a few cases. Moreover, a trained panel of tasters had severe difficulty in distinguishing between control and partially dealcoholized wines in triangular tests, and results were statistically significant only in some of the comparisons. It is concluded that this technique can be very useful for the partial dealcoholization of red wines because they hardly alter their composition and sensory characteristics. 相似文献