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91.
Ram Prakash R.J. Choudhary D.M. Phase 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(8):1242-1246
Thin films of Fe3O4 have been deposited on single crystal MgO(1 0 0) and Si(1 0 0) substrates using pulsed laser deposition. Films grown on MgO substrate are epitaxial with c-axis orientation whereas, films on Si substrate are highly 〈1 1 1〉 oriented. Film thicknesses are 150 nm. These films have been irradiated with 200 MeV Ag ions. We study the effect of the irradiation on structural and electrical transport properties of these films. The fluence value of irradiation has been varied in the range of 5 × 1010 ions/cm2 to 1 × 1012 ions/cm2. We compare the irradiation induced modifications on various physical properties between the c-axis oriented epitaxial film and non epitaxial but 〈1 1 1〉 oriented film. The pristine film on Si substrate shows Verwey transition (TV) close to 125 K, which is higher than generally observed in single crystals (121 K). After the irradiation with the 5 × 1010 ions/cm2 fluence value, TV shifts to 122 K, closer to the single crystal value. However, with the higher fluence (1 × 1012 ions/cm2) irradiation, TV again shifts to 125 K. 相似文献
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Evaluation of visco‐elastic properties of conditioned wheat kernels and their doughs using a compression test under small strain 下载免费PDF全文
97.
A comprehensive study of hazelnut oil composition with comparisons to other vegetable oils,particularly olive oil. 总被引:4,自引:0,他引:4
Benitez-Sánchez Pedro Luis León-Camacho Manuel Aparicio Ramón 《European Food Research and Technology》2003,218(1):13-19
Crude and refined hazelnut oils from different countries were characterised by major and minor compounds. Fatty acids, triacylglycerides, waxes, sterols, methyl-sterols, terpenic and aliphatic alcohols, tocopherols, tocotrienols and hydrocarbons were identified and quantified by gas chromatography and high-performance liquid chromatography. The levels of these chemical compounds in hazelnut oils together with the equivalent carbon numbers and triacylglyceride carbon numbers, were compared with the results of analyses of samples of other vegetable oils. The statistical procedure of cluster analysis was used to characterise hazelnut oils versus other edible oils. 相似文献
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Microbiological and Physicochemical Quality Changes in Frankfurters Made from Jumbo Squid (Dosidicus gigas) Mantle Muscle in the Presence and Absence of a Natural Antimicrobial Agent 下载免费PDF全文
99.
Extensively reared Iberian pigs versus intensively reared white pigs for the manufacture of frankfurters 总被引:2,自引:0,他引:2
Physico-chemical characteristics and different quality traits of the raw material (meat and adipose tissue) and the frankfurters elaborated from extensively reared Iberian pigs (IF) and intensively reared white pigs (WF) were evaluated. Hybrid frankfurters (HF) made with meat from white pigs and adipose tissue from Iberian pigs were also studied. The differences found between muscles and adipose tissues from Iberian and white pigs largely influenced the characteristics displayed by the frankfurters. Particularly remarkable are the higher amounts of substances with proven antioxidant activity such as tocopherols and phenolic compounds in tissues from Iberian pigs than in those from white pigs. No significant differences were found amongst frankfurters for their proximate composition though IF presented a higher iron content than WF and HF. IF exhibited a redder and darker colour than WF and HF. The latter were paler and showed higher hue values than IF. Concerning their fatty acid composition, IF had higher proportions of oleic acid and MUFA and smaller proportions of SFA and PUFA than WF. From a nutritional point of view, IF had a lower n-6/n-3 value than WF. The addition of adipose tissue from Iberian pigs to the HF modified its fatty acid composition compared to that of WF, significantly increasing the percentages of MUFA and reducing the proportions of PUFA, SFA and the n-6/n-3 value. Though no significant differences were found amongst frankfurters for their texture profile, a clear trend was detected, with the HF showing intermediate texture characteristics between IF and WF. 相似文献
100.
It was aimed to explore the potential of abrasives in nanometer size in friction materials (FMs). Hence six FMs were developed using micro and nano-abrasives of three types viz. alumina, SiC and silica (2%). The nano and micro composites were developed and characterized for various physical and chemical properties. The tribological performance was evaluated on a reduced scale prototype under various operating parameters and output parameters such as wear, μavg as a function of speed and pressure, load-speed sensitivity of μ and friction stability were considered to compare the performance of nano and micro-composites (NCs and MCs). It was concluded that all performance parameters were significantly and beneficially affected due to nano-fillers. Nano-silica proved to impart highest wear resistance followed by SiC and then alumina while best combination of friction properties was exhibited by composites with SiC followed by Alumina and then silica. SEM on worn surfaces of pads and discs was done to understand wear mechanism and it was clearly observed that thin coherent film on both the surfaces in case of NCs was responsible for enhanced performance. 相似文献