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991.
John Abraham V. Ramesh Saravanakumar V. V. Kulkarni K. Sivakumar Anandha Prakash Singh P. Visha 《Journal of the American Oil Chemists' Society》2014,91(1):133-141
Whole dead poultry birds obtained from commercial layer farms were assessed for fat in the whole carcass and then dry rendered in three different rendering regimens T1, T2 and T3 (temperature = 120, 130 and 140 °C and shell pressure = 1, 2 and 3 kg/cm2 respectively) and the effect on the yield and quality of the rendered chicken oil were studied. The overall fat percentage of the whole dead poultry carcass was 14.55 ± 0.17 % and the fat content of ‘greaves’ was 14.49 ± 0.38 %. In the dry batch rendering trials, the mean overall fat recovery was 24.46 ± 1.19, 26.78 ± 3.14 and 22.42 ± 2.32 % and the overall fat yield was 3.52 ± 1.72, 3.84 ± 0.44 and 3.22 ± 0.33 % of the carcass weight in T1, T2 and T3 respectively. Solvent extraction of fat could recover 96.10 ± 0.14 % of fat from ‘greaves’ which was significantly higher than the mechanical centrifugation method. Among the quality characteristics of the rendered chicken oil (RCO), moisture content ranged from 0.61 % (T2) to 1.09 % (T1) and the mean specific gravity was 0.91 at 30 °C. The FFA values of RCO obtained from the T3 rendering regimen were significantly (p < 0.05) higher than the FFA values of T2 and T1. The mean acid value, iodine number, peroxide value, saponification value and unsaponifiable matter present in RCO showed no significant difference. The fatty acid profile and calorific values were studied. The RCO was converted to biodiesel by transesterification and the physico-chemical properties of the biodiesel were studied and compared with the Indian biodiesel specification. 相似文献
992.
John L. Gardon 《Progress in Organic Coatings》1997,32(1-4):73
Aqueous binder resins are becoming increasingly diversified and encompass classical latexes, latex-like polyurethane dispersions, and various aqueous dispersion polymers. Unlike classical and urethane latexes, the dispersion polymers are synthesized in non-aqueous media, have low molecular weights and are dispersed into water by mechanical means. The preparation of classical latexes from unsaturated monomers is scientifically well understood. Modem classical latex technology provides precise particle size control and the means to impart core-shell morphology to the particles. Core-shell morphology is beneficial for improved film formation, rheology and crosslink acceptance. Polyurethane dispersions are made by extending the molecular weight of isocyanate-terminated prepolymers with aqueous diamines. Though more expensive, polyurethane dispersion binders complement classical latexes by yielding tougher and generally more solvent resistant films. The low molecular weight acrylic, alkyd, polyester and epoxy dispersion polymers have advantages in good atomization, high gloss and flow-out in film formation Current progress includes improved scientific understanding of urethane latexes and of dispersion polymers. This is paralleled by the development of novel crosslinking systems. 相似文献
993.
Hisayuki Suematsu Mamoru Mitomo Terence E. Mitchell John J. Petrovic Osamu Fukunaga Naoki Ohashi 《Journal of the American Ceramic Society》1997,80(3):615-620
Single crystals of α-Si3 N4 were annealed at 2000°–2150°C. The β phase was detected after annealing at 2150°C only when the crystals were surrounded by MgO·3Al2 O3 or Y2 O3 powders. On the other hand, no evidence of the α–β transformation was found when the crystals were annealed without additives. The solution–precipitation mechanism was concluded to be the dominant factor in the α–β transformation of Si3 N4 . 相似文献
994.
Yolk and embryonic total lipids were extracted from spotted dogfish eggs at two developmental stages. Total lipids were fractionated
into neutral lipids (NL) and polar lipids (PL), and the fatty acid composition of each group was determined. Yolk lipid composition
was found to be quantitatively different (NL/PL≊1) from embryo lipid composition (NL/PL≊0.5), for both stages of development.
However, individual fatty acid composition did not differ from younger to older eggs for either yolk or embryo. There were
significant differences (p<0.05) in major fatty acid groups from yolk and embryonic PL for saturated fatty acids, monounsaturated
fatty acids (MUFA) and n−3 polyunsaturated fatty acids (PUFA) for younger eggs, and for MUFA and n−3 PUFA for older eggs.
For NL, only MUFA composition from the oldest eggs showed differences between yolk and embryo. Results are discussed in terms
of embryonic needs for highly unsaturated fatty acid (HUFA) biosynthesis, as well as to provide some explanations for the
unusually high levels of 20∶4n−6 in both yolk and embryonic neutral lipids and polar lipids. 相似文献
995.
Murat Bengisu Osman T. Inal John R. Hellmann 《Journal of the American Ceramic Society》1990,73(2):346-351
Dynamic consolidation techniques were employed to investigate the retention of tetragonal zirconia and degree of consolidation in alumina/zirconia powder compacts. Heating the specimens prior to explosive shock compaction increased the tetragonal-phase retention significantly. Low shock pressures yielded no macrocracking, although final densities were low (60% to 70% of the theoretical density). Heat treatment following dynamic consolidation enhanced the retention of the tetragonal zirconia polymorph regardless of the shock pressure employed. Compact densities were increased to over 90% of theoretical at relatively low sintering temperatures (1300°C). Hardness, toughness, and Young's modulus of the compacts were comparable to those achieved in composites that were synthesized using more conventional techniques. Dynamic compaction offers an alternative method for the fabrication of zirconia-toughened alumina ceramics. 相似文献
996.
The reactivity of O-, T- and R-phases of the high pressure-high temperature (HPHT) polymerized C60 towards gaseous fluorine in the temperature range of 50-250 °C was investigated. The reaction products were characterized by FTIR, powder X-ray diffraction, SEM, EDX, and VTP-EIMS to determine the bulk stoichiometries, bonding patterns, phase compositions, crystalline structures and thermal decomposition behavior of the fluorinated polymers. At 1 h isothermal treatment duration, fluorinated products with various bulk stoichiometries were obtained from different polymer phases with the R-phase showing the highest fluorine uptake. At 250 °C, all C60 polymers showed partial decomposition to unfluorinated C60 monomer under fluorine atmosphere. At 200 °C, the fluorination of R-phase yielded a pure fluoropolymer most likely having a {C60Fx}n (x = 36-44) composition. The same fluoropolymer was presumably obtained from O- and T-phases in lower yields. The linear chain structure was suggested for this new fluorocarbon polymer in agreement with the molecular mechanics modeling calculations. 相似文献
997.
Polyethylene multiwalled carbon nanotube composites 总被引:4,自引:0,他引:4
Tony McNally Petra Pötschke Michael Murphy Steven E.J. Bell Daniel Bein John Paul Quinn 《Polymer》2005,46(19):8222-8232
Polyethylene (PE) multiwalled carbon nanotubes (MWCNTs) with weight fractions ranging from 0.1 to 10 wt% were prepared by melt blending using a mini-twin screw extruder. The morphology and degree of dispersion of the MWCNTs in the PE matrix at different length scales was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and wide-angle X-ray diffraction (WAXD). Both individual and agglomerations of MWCNTs were evident. An up-shift of 17 cm−1 for the G band and the evolution of a shoulder to this peak were obtained in the Raman spectra of the nanocomposites, probably due to compressive forces exerted on the MWCNTs by PE chains and indicating intercalation of PE into the MWCNT bundles. The electrical conductivity and linear viscoelastic behaviour of these nanocomposites were investigated. A percolation threshold of about 7.5 wt% was obtained and the electrical conductivity of PE was increased significantly, by 16 orders of magnitude, from 10−20 to 10−4 S/cm. The storage modulus (G′) versus frequency curves approached a plateau above the percolation threshold with the formation of an interconnected nanotube structure, indicative of ‘pseudo-solid-like’ behaviour. The ultimate tensile strength and elongation at break of the nanocomposites decreased with addition of MWCNTs. The diminution of mechanical properties of the nanocomposites, though concomitant with a significant increase in electrical conductivity, implies the mechanism for mechanical reinforcement for PE/MWCNT composites is filler-matrix interfacial interactions and not filler percolation. The temperature of crystallisation (Tc) and fraction of PE that was crystalline (Fc) were modified by incorporating MWCNTs. The thermal decomposition temperature of PE was enhanced by 20 K on addition of 10 wt% MWCNT. 相似文献
998.
Radical Scavenging Activity of Lipophilized Products from Lipase-Catalyzed Transesterification of Triolein with Cinnamic and Ferulic Acids 总被引:3,自引:0,他引:3
Lipase-catalyzed transesterification of triolein with cinnamic and ferulic acids using an immobilized lipase from Candida antarctica (E.C. 3.1.1.3) was conducted to evaluate the antioxidant activity of the lipophilized products as model systems for enhanced protection of unsaturated oil. The lipophilized products were identified using ESI-MS. Free radical scavenging activity was determined using the DPPH radical method. The polarity of the solvents proved important in determining the radical scavenging activity of the substrates. Ferulic acid showed much higher radical scavenging activity than cinnamic acid, which has limited activity. The esterification of cinnamic acid and ferulic acid with triolein resulted in significant increase and decrease in the radical scavenging activity, respectively. These opposite effects were due to the effect of addition of electron-donating alkyl groups on the predominant mechanism of reaction (hydrogen atom transfer or electron transfer) of a species with DPPH. The effect of esterification of cinnamic acid was confirmed using ethyl cinnamate which greatly enhances the radical scavenging activity. Although, compared to the lipophilized cinnamic acid product, the activity was lower. The radical scavenging activity of the main component isolated from lipophilized cinnamic acid product using solid phase extraction, monocinnamoyl dioleoyl glycerol, was as good as the unseparated mixture of lipophilized product. Based on the ratio of a substrate to DPPH concentration, lipophilized ferulic acid was a much more efficient radical scavenger than lipophilized cinnamic acid. 相似文献
999.
Izumi Satake John H. XinTu Tianming Aran HansuebsaiKenji Ando Tetsuya SatoKanji Kajiwara Seiji Ohsawa 《Progress in Organic Coatings》2011,72(3):528-540
This article compares color assessments of automotive exteriors at four locations in China, Thailand and Japan. This study employed painted panels of twelve colors, thirty sensory words and fifteen pairs of emotion variables. It also used reference figures of nine cars that included four styling categories, namely sedans, compacts, sport utility vehicles and sports cars. The results of like-dislike tests revealed that basic automotive exterior colors, such as black, white and red, were highly preferred across locations. However, geographical differences are apparent in the preference for some non-basic colors. To elucidate these geographical differences, a Chi-square test and principal component analysis were performed on the data on emotion variables. The results revealed both similarities and differences in color preferences among the four locations. Color preferences were similar in Hong Kong and Shanghai when simply evaluated by color samples. However, similar preferences for automotive exterior colors were observed in Hong Kong, Kyoto and Bangkok, but not in Shanghai. These results suggest that there is fluctuation in the emotion evoked by a color when the color is considered in the context of automotive exteriors. Therefore, this study indicates that automotive sales can be secured in the global marketplace by creating a single palette of exterior colors based on similar color preferences across countries. However, these results also indicate that preparing market-specific automotive-color line-ups can be an effective marketing strategy. 相似文献
1000.
Alcantara EH Lomeda RA Feldmann J Nixon GF Beattie JH Kwun IS 《Molecular nutrition & food research》2011,55(10):1552-1560
Scope: Zinc is implicated as an activator for bone formation, however, its influence on bone calcification has not been reported. This study examined how zinc regulates the bone matrix calcification in osteoblasts. Methods and Results: Two osteoblastic MC3T3‐E1 cell subclones (SC 4 and SC 24 as high and low osteogenic differentiation, respectively) were cultured in normal osteogenic (OSM), Zinc deficient (Zn–, 1 μM), or adequate (Zn+, 15 μM) media up to 20 days. Cells (SC 4) were also supplemented with (50 μg/mL) or no ascorbic acid (AA) in combination with Zinc treatment. Zn– decreased collagen synthesis and matrix accumulation. Although AA is essential for collagen formation, its supplementation could not compensate for Zinc deficiency‐induced detrimental effects on extracellular matrix mineralization. Zn– also decreased the medium and cell layer alkaline phosphatase ALP activity. This decreased ALP activity might cause the decrease of Pi accumulation in response to Zn–, as measured by von Kossa staining. Ca deposition in cell layers, measured by Alizarin red S staining, was also decreased by Zn–. Conclusion: Our findings suggest that zinc deprivation inhibits extracellular matrix calcification in osteoblasts by decreasing the synthesis and activity of matrix proteins, type I collagen and ALP, and decreasing Ca and Pi accumulation. Therefore zinc deficiency can be considered as risk factor for poor extracellular matrix calcification. 相似文献