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91.
Seed oils of Origanum onites L. from the Antalya and Mugla regions and O. vulgare L. from the Kirklareli region of Turkey were extracted with hexane in a Soxhlet apparatus. The oil yields were 14.1–20.0
and 18.5%, respectively. FA compositions of the seed oils were determined by GC and GC/MS. Twenty FA were identified in both
O. onites and O. vulgare seeds. The major FA of both species were linolenic (56.3–57.0%; 61.8%), linoleic (21.5–21.7%; 18.8%), oleic (8.7–8.9%; 5.9%),
palmitic (5.9–6.5%; 5.5%), stearic (2.1–2.4%; 2.1%), and (Z)-11-octadecenoic (0.6–0.8%; 0.5%), respectively. 相似文献
92.
Influences of Solid Loadings on the Microstructures and the Optical Properties of Yb:YAG Ceramics
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Xuewei Ba Yubai Pan Yanping Zeng Wenbin Liu Benxue Jiang Jing Liu 《International Journal of Applied Ceramic Technology》2015,12(2):418-425
Transparent Y2.85Yb0.15Al5O12 ceramics were prepared using an aqueous tape casting and vacuum sintering method. The rheological properties were measured by a rheometer. The results indicate high quality tapes, and ceramics can be obtained by increasing the solid loading of the corresponding slurries. The densities of the tapes increase from 2.42 to 2.69 g/cm3 by increasing the solid loadings from 35 to 50 vol%. The corresponding green body densities range from 52.7 to 57.1% of the theoretical. The solid loading suitable for fabricating transparent Yb:YAG ceramics should be higher than 45 vol%. 相似文献
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V. Švor?ík N. Kasálková K. Záruba L. Ba?áková V. Lisá H. Gbelcová A. Macková 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(11):1904-1910
Polyethylene (PE) was irradiated with inert Ar plasma, and the chemically active PE surface was grafted with Au nanoparticles. The composition and the structure of the modified PE surface were studied using X-ray photoelectron spectroscopy (XPS) and Rutherford backscattering spectroscopy (RBS). Changes in the surface wettability were determined from the contact angle measured in a reflection goniometer. The changes in the surface roughness and morphology were followed by atomic force microscopy (AFM). The modified PE samples were seeded with rat vascular smooth muscle cells (VSMC) or mouse NIH 3T3 fibroblasts, and their adhesion and proliferation were studied. We found that plasma discharge and Au grafting lead to dramatic changes in the surface morphology and roughness of PE. The Au nanoparticles were found not only on the sample surface, but also in the sample interior up to the depth of about 100 nm. In addition, plasma modification of the PE surface, followed with grafting Au-nanoparticles, significantly increased the attractiveness of the PE surface for the adhesion and growth of VSMC, and particularly for mouse embryonic 3T3 fibroblasts. 相似文献
96.
The use of 0.02 or 0.05% chitosan is proposed to reduce from 450 to 150mgkg(-1) the SO(2) required to preserve pork burgers aerobically packed and stored at 2°C for up to 21days under retail display conditions. The effects of chitosan and/or sulfite addition and the storage time were determined in fresh (color deterioration, lipid oxidation, pH, total viable counts, Escherichia coli and coliforms, Salmonella, appearance and odor) and cooked (appearance, odor, flavor and texture) burgers. The addition of either 0.02 or 0.05% chitosan was not detected by sensory analysis, and extended the shelf life of low-SO(2) burgers from 7 to 14days. Chitosan enhanced the preservative effects of sulfite at a low dose, acting on the main causes of meat deterioration (bacterial spoilage, color stability and lipid oxidation), and provided good sensory properties to fresh and cooked pork burgers. 相似文献
97.
西藏金河水电站采用GIS全封闭组合电器,它改善了恶劣环境对电气设备的危害,提高了供电的可靠性及电站综合自动化水平,有利于运行管理。GIS设备在金河电站的成功应用说明,GIS完全可以在西藏地区推广应用.这也完全符合电力行业的发展趋势。 相似文献
98.
针对基于无人机中继的星地认知网络,提出了两种波束成形(beamforming, BF)算法,通过对各种干扰进行抑制,实现系统间的频谱共享。具体而言,在基于无人机中继的卫星网络作为次级网络、地面网络作为主网络的情况下,以无人机最大发射功率和主用户所受干扰为约束条件,建立次级用户信干噪比最大化准则的优化问题;接下来在已知次级用户统计信道状态信息的条件下,提出一种基于迭代的BF算法对优化问题进行求解;更进一步,为了降低迭代算法的实现复杂度,提出了一种基于迫零的BF算法。最后,计算机仿真验证了所提两种波束成形方案的正确性与有效性。 相似文献
99.
为了适应未来红外焦平面探测器系统小型化、集成化和高精度的发展要求,采用了热蒸发方法分别在InP衬底和InGaAs探测器上实现了中心波长为1.38μm滤光膜的片上集成。利用偏光显微镜、原子力显微镜(AFM)和扫描电子显微镜(SEM)以及红外傅里叶光谱(FTIR)等实验手段研究了滤光膜的表面界面形貌和光学性能,结果显示,滤光膜为法布里-珀罗三谐振腔结构,与膜系设计一致;滤光膜中心波长为1.38μm,透射率在60%左右。对集成滤光膜InGaAs器件的电学和光学性能测试分析表明,滤光膜制备工艺对器件的电流电压特性和噪声基本没有影响;而集成滤光膜器件的响应要优于滤光膜分离器件的性能。 相似文献
100.