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11.
W. W. Marion S. T. Maxon R. M. Wangen 《Journal of the American Oil Chemists' Society》1970,47(10):391-392
Total lipid and phospholipid contents of liver, skin and depot fat from yearling hen turkeys have been studied. Liver lipid
averaged 88.5 mg/g wet tissue; skin, 385.0 and depot fat, 753.5. Phospholipids comprised 32.05% of total lipid of liver, but
only 0.81% of skin and 0.46% of depot fat. Fatty acids of liver differed from those of skin or depot fat by larger amounts
of 16∶0, 18∶0, 20∶4, 22∶0 and 24∶0, and smaller amounts of 16∶1, 18∶1, 18∶2, 18∶3 and 20∶0. Similarity existed between skin
and depot fat.
Journal Paper No. J-6473 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 1696. 相似文献
12.
Mixtures of 90, 80, and 70 percent by weight bisphenol-A-polycarbonate (PC) and 10, 20, and 30 percent by weight styrene maleic anhydride (SMA) copolymer were melt-blended in a single screw extruder. Differential scanning calorimetry (DCS) and scanning electron microscopy (SEM) were used to determine the miscibility of the blends. The viscosity, as a function of shear rate and temperature, was measured by an Instron capillary viscometer. The notched impact strength as a function of temperature was measured by an Izod impact tester. The results of DSC showed two glass transition temperatures which merged slightly towards each other, indicating marginal miscibility of these blends. There was a decrease in viscosity as the fraction of SMA copolymer was increased. The most significant decrease occurred with the initial addition of SMA copolymer. The viscosity also decreased with increases in temperature. The impact strength of the blends was also dependent on SMA copolymer content. The blends showed six to ten times lower impact strengths at room temperature than the 100 percent polycarbonate. SEM analysis helped to determine the reason why the impact strength was lower for the blends. High magnification showed the presence of SMA copolymer inclusions dispersed throughout the PC matrix. These inclusions, which increased in size as SMA copolymer content was increased, acted as defects in the system. 相似文献
13.
T. S. Wilson J. P. Bearinger J. L. Herberg J. E. Marion III W. J. Wright C. L. Evans D. J. Maitland 《应用聚合物科学杂志》2007,106(1):540-551
Aliphatic urethane polymers have been synthesized and characterized, using monomers with high molecular symmetry, to form amorphous networks with very uniform supermolecular structures, which can be used as photo‐thermally actuable shape memory polymers (SMPs). The monomers used include hexamethylene diisocyanate (HDI), trimethylhexamethylenediamine (TMHDI), N,N,N′,N′‐tetrakis(hydroxypropyl)ethylenediamine (HPED), triethanolamine (TEA), and 1,3‐butanediol (BD). The new polymers were characterized by solvent extraction, NMR, XPS, UV/VIS, DSC, DMTA, and tensile testing. The resulting polymers were found to be single phase amorphous networks with very high gel fraction, excellent optical clarity, and extremely sharp single glass transitions in the range of 34–153°C. Thermomechanical testing of these materials confirms their excellent shape memory behavior, high recovery force, and low mechanical hysteresis (especially on multiple cycles), effectively behaving as ideal elastomers above Tg. We believe these materials represent a new and potentially important class of SMPs, and should be especially useful in applications such as biomedical microdevices. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
14.
A kinetic study of the anionic polymerization of ethylene oxide has been made in tetrahydrofuran at 20°C, with the cryptate Cs+ + [TC] as counterion, [TC] being a spheroidal macrotricyclic ligand. Conductance measurements have been made on THF solutions of ?4BCs + [TC]. Ionic associations higher than cryptated ion pairs are negligible for living end concentrations lower than 3 × 10?4 moll?1. k± and the alkoxide ion pair dissociation constant KD were determined from both sets of kinetic data obtained with and without added salt knowing the value of k? from kinetic data performed with K+ + [222] as counterion. Free alkoxide ions are about twenty times more reactive than cryptated caesium ion pairs. 相似文献
15.
Daniel Caurant Odile Majérus Edward Fadel Marion Lenoir Christel Gervais Olivier Pinet 《Journal of the American Ceramic Society》2007,90(3):774-783
Crystallization of the poorly durable Na2 MoO4 phase able to incorporate radioactive cesium must be avoided in SiO2 –Al2 O3 –B2 O3 –Na2 O–CaO glasses developed for the immobilization of Mo-rich nuclear wastes. Increasing amounts of B2 O3 and MoO3 were added to a SiO2 –Na2 O–CaO glass, and crystallization tendency was studied. Na2 MoO4 crystallization tendency decreased with the increase of B2 O3 concentration whereas the tendency of CaMoO4 to crystallize increased due to preferential charge compensation of BO4 − entities by Na+ ions. 29 Si MAS NMR showed that molybdenum acts as a reticulating agent in glass structure. Trivalent actinides surrogate (Nd3+ ) were shown to enter into CaMoO4 crystals formed in glasses. 相似文献
16.
Associations between apolipoprotein E genotype and circulating F<Subscript>2</Subscript>-isoprostane levels in humans 总被引:1,自引:0,他引:1
Dietrich M Hu Y Block G Olano E Packer L Morrow JD Hudes M Abdukeyum G Rimbach G Minihane AM 《Lipids》2005,40(4):329-334
Apolipoprotein E (apoE), an important determinant of plasma lipoprotein metabolism, has three common alleles (ε2, ε3, and
ε4). Population studies have shown that the risk of diseases characterized by oxidative damage, such as coronary heart disease
and Alzheimer’s disease, is significantly higher in ɛ4 carriers. We evaluated the association between apoE genotypes and plasma
F2-isoprostane levels, an index of lipid peroxidation, in humans. Two hundred seventy-four healthy subjects (104 males, 170
females; 46.9±13.0 yr; 200 whites, 74 blacks; 81 nonsmokers, 64 passive smokers, and 129 active smokers) recruited for a randomized
clinical antioxidant intervention trial were included in this analysis. ApoE genotype was determined by PCR and restriction
enzyme digestion. Free plasma F2-isoprostane was measured by GC-MS. Genotype groups were compared using multiple regression analysis with adjustment for sex,
age, race, smoking status, body mass index, plasma ascorbic acid, and β-carotene. Subjects with ε3/ε4 and ε4/ε4 genotype (ε4-carriers)
and with ε2/ε3 and ε3/ε3 (non-ε4-carriers) were pooled for analysis. In subjects with high cholesterol levels (total cholesterol
above 200 mg/dl), plasma F2-isoprostane levels were 29% higher in ε4 carriers than in non-ε4-carriers (P=0.0056). High-cholesterol subjects that are ε4 carriers have significantly higher levels of lipid peroxidation as assessed
by circulating F2-isoprostane levels. 相似文献
17.
Peirui Zhang Fangqing Weng Ernest Koranteng Duyu Guo Pengfei Cao Qiangxian Wu 《应用聚合物科学杂志》2021,138(10):49963
Castor oil (CO) is an environmentally friendly renewable green resource and ideal alternative to petroleum resources. The preparation of high strength and high toughness castor oil-based polyurethane prepolymer (COPU) composites has significant applications such as supporting material and engineering plastic sheet. In this study, unmodified clam shell powder (CSP) with a unique CaCO3-proteoglycan structure was used as a filler to prepare compatible reinforced COPU composite materials. Investigation of the mechanical properties revealed that the elastic modulus of the composite COPU reinforced with 50 wt% of CSP had increased to 5859.0 ± 8.4 MPa representing 187.77% to obtain stiffer and stronger material over pure COPU (2036.6 ± 196.9 MPa). Moreover, the scanning electron microscopy, thermogravimetric analysis and contact angle results demonstrated that the reinforced COPU composites have better compatibility, thermal stability, and water resistance than pure COPU. This work will promote the application prospects of CO-based polyurethane. 相似文献
18.
Younes Seifi Suriadi Suriadi Ernest Foo Colin Boyd 《International Journal of Information Security》2015,14(3):221-247
To prevent unauthorized access to protected trusted platform module (TPM) objects, authorization protocols, such as the object-specific authorization protocol (OSAP), have been introduced by the trusted computing group (TCG). By using OSAP, processes trying to gain access to the protected TPM objects need to prove their knowledge of relevant authorization data before access to the objects can be granted. Chen and Ryan’s 2009 analysis has demonstrated OSAP’s authentication vulnerability in sessions with shared authorization data. They also proposed the Session Key Authorization Protocol (SKAP) with fewer stages as an alternative to OSAP. Chen and Ryan’s analysis of SKAP using ProVerif proves the authentication property. The purpose of this paper was to examine the usefulness of Colored Petri Nets (CPN) and CPN Tools for security analysis. Using OSAP and SKAP as case studies, we construct intruder and authentication property models in CPN. CPN Tools is used to verify the authentication property using a Dolev–Yao-based model. Verification of the authentication property in both models using the state space tool produces results consistent with those of Chen and Ryan. 相似文献
19.