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61.
A method for isolation and quantitation of cellular free fatty acid has been developed. When this method was used to quantitate
the free fatty acid content of various cells and tissues, their levels of free fatty acids were found to vary over a wide
range. In comparing tissue culture cells having different levels of free fatty acid, it was demonstrated that the conditions
of culture and the type of serum in the medium are not responsible for the difference in levels. Isotopic studies have shown
that the cellular free fatty acid is not biosynthesized, but is derived from the free fatty acid of the medium. Preliminary
studies on the fate of the intracellular free fatty acid and a discussion of possible factors controlling the level of this
compound in cells are presented. 相似文献
62.
Barbara Przyjazna 《Polymer》2004,45(8):2559-2566
The series of new dyes, which structures are based on 6H-indolo[2,3-b]quinoxaline skeleton that possess characteristic electronic absorption band at a boundary of UV and visible light were tested as potential light absorbing chromophores for photoinitiated polymerization.The studied dyes can be classified into two different groups. The first is the group, so called ‘the branched dyes’, which structures possess the part of molecule that can rotate without restraints and are characterized by low photoinitiation ability. The second, planar and rigid group of molecules provides another chromophores, which possess quite different properties in comparison to that observed for the branched dyes. Their photoinitiation ability is comparable to that observed for many commercially available photoinitiating systems.The location of electronic absorption spectra at a boundary of UV and visible light makes the tested dyes the good candidates for the photoinitiating system applied in dental restorative materials. Their high molar absorption coefficient allows to decrease the dyes concentration in dental formulation in comparison to commonly used camphorquinone. 相似文献
63.
Thomas M. Odell Chong-Hua Xu Paul W. Schaefer Barbara A. Leonhardt De-Fu Yao Xiang-De Wu 《Journal of chemical ecology》1992,18(12):2153-2159
Pheromone traps baited with (+)-disparlure,cis-7,8-epoxy-2methyocta-decane, captured males ofLymantria dispar, L. monacha, andL. mathura in northeastern People's Republic of China.L. dispar responded to the addition of olefin to (+)-disparlure-baited traps in a negative doseresponse manner. Observations on site and seasonal capture ofL. dispar andL. mathura are discussed.Lepidoptera: Lymantriidae. 相似文献
64.
Garrett BC Dixon DA Camaioni DM Chipman DM Johnson MA Jonah CD Kimmel GA Miller JH Rescigno TN Rossky PJ Xantheas SS Colson SD Laufer AH Ray D Barbara PF Bartels DM Becker KH Bowen KH Bradforth SE Carmichael I Coe JV Corrales LR Cowin JP Dupuis M Eisenthal KB Franz JA Gutowski MS Jordan KD Kay BD Laverne JA Lymar SV Madey TE McCurdy CW Meisel D Mukamel S Nilsson AR Orlando TM Petrik NG Pimblott SM Rustad JR Schenter GK Singer SJ Tokmakoff A Wang LS Wettig C Zwier TS 《Chemical reviews》2005,105(1):355-390
65.
Fernanda Fabbri Gondim Lucas Galhardo Pimenta Tienne Barbara de Salles Macena da Cruz Erica Gervasoni Chaves Augusto Cesar de Carvalho Peres Maria de Fatima Vieira Marques 《应用聚合物科学杂志》2021,138(14):50157
In this work, PVDF composites containing 0.2% (m/m) of carbon nanotubes (MWCNTs), PVDF with 5.0% (m/m) of zinc oxide (ZnO), and composites containing both particles in the same contents in the matrix were melt processed in a mini-extruder machine with double screws, using the counter-rotation mode. Composites were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), dynamic-mechanical analysis (DMA), and contact angle tests (CA). The samples presented the predominance of the α phase, with an increased degree of crystallinity as well as an increase in dimensional stability by incorporating both fillers, showing a synergistic effect between these particles, as shown on FTIR, DSC, and XRD results. SEM images showed a good dispersion of high aspect ratio particles. In general, DMA and TGA analysis showed that composites had not decreased their thermal and mechanical performance when compared to neat PVDF. Results of CA analysis showed an increase in the hydrophobicity of the sample containing MWCNTs. Permeability tests were also performed using a differential pressure system, combining high temperature and pressure, obtaining permeability measures and time lag. This work presents an alternative of composite materials, suggesting its application in the internal pressure sheath layers of oil and gas flexible pipes. 相似文献
66.
Barbara Wachowicz Koryna Lewandowska Anna Popek Waldemar Karwowski Tadeusz Marek 《人机工程学与制造业中的人性因素》2016,26(2):266-284
The primary purpose of this paper is to discuss the role of empathy in the design of advanced systems in manufacturing and service industries in order to ensure suitable working conditions for employees from the social and technological point of view. The origins and components of empathy are briefly reviewed. The neural underpinnings of three components of empathy, including cognitive, emotional, and behavioral aspects, are considered in the context of human–human and human–machine interactions, as well as design of working environments. Finally, the potential advantages of applying empathy‐related knowledge to the design and development of human‐centered technology are discussed. 相似文献
67.
68.
Neural Processing Letters - Albeit automated classifiers offer a standard tool in many application areas, there exists hardly a generic possibility to directly inspect their behavior, which goes... 相似文献
69.
Mariana G. Figueiro Brittany Wood Barbara Plitnick Mark S. Rea 《Journal of the Society for Information Display》2013,21(10):417-421
Self‐luminous electronic devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression. The present paper investigated if light from a 178‐cm (70 in.) television suppressed melatonin. Results showed that light from televisions does not impact melatonin levels in the evening. 相似文献
70.
This article presents the findings of an exploratory study of education graduate students’ information-seeking behavior and attitudes. Qualitative data included interviews with education students, focusing on their research habits, and analyzed from phenomenographic approach that focused on variations in individuals’ experiences. The quantitative analysis stemmed from participants’ responses to the survey of their information-seeking behavior. A comparison of interview participants and survey respondents’ search skills, research strategies, and attitudes toward previous library instruction illustrate the wide variation in students’ abilities and experiences between the groups. This suggests the need for further analysis of these students’ information seeking behaviors. 相似文献