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31.
S.M. Crawford S.J. Moeller H.N. Zerby K.M. Irvin P.S. Kuber S.G. Velleman T.D. Leeds 《Meat science》2010,84(4):607-612
The effect of, and associations between, loin muscle morphology and pork quality indicator traits were assessed at three cooked temperatures in loin chops from 38 purebred Berkshire and 52 purebred Landrace swine. Three loin chops from each pig were randomly assigned to cooked temperature treatments of 62, 71, or 79 °C and loin tenderness was assessed as Warner–Bratzler shear force (WBSF). Cooked temperature (P < 0.001), breed (P < 0.001) and breed × cooked temperature (P < 0.001) effects influenced loin chop WBSF, whereby WBSF increased as cooked temperature increased. Chops from Landrace pigs had greater WBSF at each cooked temperature compared with chops from Berkshire pigs. Chops from Landrace pigs became less tender with increasing cooked temperature, whereas chops from Berkshire pigs became less tender only when cooked to 79 °C. In loins from Landrace pigs, Minolta a1 at 62 °C (R2 = 0.07), and average muscle fiber diameter at 71 °C and 79 °C (R2 = 0.07 and 0.24, respectively), contributed to WBSF variation. In contrast, for loins from Berkshire pigs, loin ultimate pH and intramuscular fat percentage accounted for 27% and 30% of the variation in WBSF at 62 °C and 71 °C, respectively, and loin ultimate pH accounted for 7% of variation in WBSF at 79 °C. Results suggest that loins from Berkshire pigs have properties that resist toughening at greater cooked temperatures and that associations between quality measures and loin tenderness differ between Landrace and Berkshire pigs. 相似文献
32.
Iron as ferrocene was added to furfuryl alcohol. The doped monomer was polymerized to polyfurfuryl alcohol which was carbonized to heat treatment temperatures of 725–1090 K. Thin sections of these carbons were examined by high resolution electron microscopy to reveal the stacking arrangements of the constituent layers and the state of dispersion of the iron added as ferrocene. In the polyfurfuryl alcohol it was not possible to detect any aggregates of iron. However, small aggregates, ~5 nm, appear at 725 K and are distinct at 943 K. Significant catatylic graphitization by iron particles occurs at the relatively low temperature of 875 K (600°C) to produce a turbostratic graphite. Small aggregates of iron, ~20 nm diameter, are responsible for this form of graphitization, the particles having mobility or remaining stationary within the carbon matrix. An activation energy of 400 kJ mol?1 is derived for this form of graphitization. 相似文献
33.
在这个习惯了用视觉说话的年代里,还有什么能比一段影像更能迅速地打动人心?而此时,潮流也开始跳脱T台,真正地进入影像世界,在场景、人物、光影帮助下诠释设计的内在含义。女人,本身就是潮流的一部分,她们的爱幻想、情绪化、生活多姿多彩也许就是时尚工业的根基。灵感从女人中来、被女人认同、最后被女 相似文献
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PN Amess J Baudin J Townsend J Meek SC Roth BG Neville JS Wyatt A Stewart 《Canadian Metallurgical Quarterly》1998,40(11):724-730
Osteoporotic fractures, and in particular, hip fractures result in significant morbidity and mortality. Low bone mass is the main risk factor of enhanced bone fragility, resulting in an increased risk for hip fracture. Bone density of osteoporotic women with and without hip fractures show a considerable overlap. Therefore, other bone-independent factors also play an important role for the development of hip- and other osteoporotic fractures. One other important factor is falling. In 90% of hip fractures falling was involved [10-15], but only 5% or less of these falls resulted in a subsequent fracture. The view that adequate exercise is beneficial for skeletal health of children and for prevention and treatment of osteoporosis in adults is supported primarily by two lines of evidence: longitudinal and cross-sectional trials in children and young adult athletes showing a significant increase of muscle- and bone mass after strenuous (children) or chronic exercise (athletes) as compared to normally active (children) or sedentary control subjects. What are the potential benefits and limits of specific exercise programs with respect to bone mass, prevention of falls and fractures? In this review these questions are discussed and a specific exercise program in osteoporotic patients with fractures is delineated. 相似文献
37.
LJ Huang FC Chang KH Lee JP Wang CM Teng SC Kuo 《Canadian Metallurgical Quarterly》1998,6(12):2261-2269
2-Amino (6), 2-alkylamino (7-8), 2-methoxy (9), 2-acetamido (10), and 5,8-diacetoxy (11) derivatives of the lead compound 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone (4) were synthesized, together with 6,7-dichloro-5,8dimethoxy-1,4-naphthoquinone (5), a positional isomer of 4. Antiplatelet, antiinflammatory, and antiallergic activities were evaluated, and most compounds were quite potent in all assays. Compounds 5 and 9-11 were especially active; however, 5 was ineffective against neutrophil superoxide formation, and 10 was ineffective against mast cell degranulation. 相似文献
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Abdul Rahman Mohtasebzadeh Longfei Ye Thomas M. Crawford 《International journal of molecular sciences》2015,16(8):19769-19779
We study magnetic-field directed self-assembly of magnetic nanoparticles onto templates recorded on perpendicular magnetic recording media, and quantify feature width and height as a function of assembly time. Feature widths are determined from Scanning Electron Microscope (SEM) images, while heights are obtained with Atomic Force Microscopy (AFM). For short assembly times, widths were ~150 nm, while heights were ~14 nm, a single nanoparticle on average with a 10:1 aspect ratio. For long assembly times, widths approach 550 nm, while the average height grows to 3 nanoparticles, ~35 nm; a 16:1 aspect ratio. We perform magnetometry on these self-assembled structures and observe the slope of the magnetic moment vs. field curve increases with time. This increase suggests magnetic nanoparticle interactions evolve from nanoparticle–nanoparticle interactions to cluster–cluster interactions as opposed to feature–feature interactions. We suggest the aspect ratio increase occurs because the magnetic field gradients are strongest near the transitions between recorded regions in perpendicular media. If these gradients can be optimized for assembly, strong potential exists for using perpendicular recording templates to assemble complex heterogeneous materials. 相似文献
40.
Lewis TA Paszczynski A Gordon-Wylie SW Jeedigunta S Lee CH Crawford RL 《Environmental science & technology》2001,35(3):552-559
A reaction pathway is proposed to explain the formation of end products during defined chemical reactions between carbon tetrachloride (CCl4) and either metal complexes of pyridine-2,6-bis(thiocarboxylic acid) (PDTC) or pure cultures of Pseudomonas stutzeri KC. The pathway includes one-electron reduction of CCl4 by the Cu(II):PDTC complex, condensation of trichloromethyl and thiyl radicals, and hydrolysis of a labile thioester intermediate. Products detected were carbon dioxide, chloride, carbonyl sulfide, carbon disulfide, and dipicolinic acid. Spin-trapping and electrospray MS/MS experiments gave evidence of trichloromethyl and thiyl radicals generated by reaction of CCl4 with PDTC and copper. Experiments testing the effects of transition metals showed that dechlorination by PDTC requires copper and is inhibited by cobalt but not by iron or nickel. PDTC was shown to react stoichiometrically rather than catalytically without added reducing equivalents. With added reductants, an increased turnover was seen along with increased chloroform production. 相似文献