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951.
Gordon G. Allison Catherine MorrisJohn Clifton-Brown Susan J. ListerIain S. Donnison 《Biomass & bioenergy》2011,35(11):4740-4747
We report on a replicated spaced-plant trial in Wales of 244 diverse Miscanthus accessions grouped by classical taxonomy into M. sinensis, M. sacchariflorus and M. x giganteus. Large differences in cell wall composition were detected between taxonomic groups. Significantly higher concentrations of NDF (88.19, 85.59 and 85.03 %DW; S.E.D. of 0.300; P < 0.001); ADL (11.76, 10.15 and 9.07 %DW; S.E.D. of 0.087; P < 0.001) and cellulose (47.09, 42.94 and 42.50 %DW; S.E.D. of 0.255; P < 0.001); and significantly lower concentrations of hemicellulose (29.43, 32.50 and 33.46 %DW; S.E.D. of 0.130; P < 0.001) were present in the samples from M. x giganteus compared to the other groups. Growth year and the interaction between taxonomic group and growth year had smaller significant effects. Strong correlations were found between ADL and cellulose (R = 0.72), and hemicellulose (R = −0.76) in the M. x giganteus samples but correlations were weaker for M. sacchariflorus (R = 0.66 and −0.59) and M. sinensis (R = 0.46 and −0.40). Eleven genotypes had been assessed previously in the U.K. during the European Miscanthus Improvement (EMI) programme. These generally had higher concentrations of ADL and hemicellulose, and lower concentrations of cellulose than were reported for the U.K. site during the EMI study. These results suggest that cell wall composition and ADL concentration in particular, is highly stable between growth years but is affected by site location. Furthermore, there are differences in cell wall composition between Miscanthus taxonomic groups that may prove valuable for breeding new varieties that are compositionally matched to conversion process. 相似文献
952.
Alex GoldsteinJeffrey M. Gordon 《Solar Energy Materials & Solar Cells》2011,95(2):624-629
Recently identified fundamental classes of dual-mirror double-tailored nonimaging optics have the potential to satisfy the pragmatic exigencies of concentrator photovoltaics. Via a comprehensive survey of their parameter space, including raytrace verification, we identify champion high-concentration high-efficiency designs that offer unprecedented optical tolerance (i.e., sensitivity to off-axis orientation) - a pivotal figure-of-merit with a basic bound that depends on concentration, exit angle, and effective solar angular radius. For comparison, results for the best corresponding dual-mirror aplanatic concentrators are also presented. 相似文献
953.
The reasons leading to the in vivo failure of three Acumatch M-series titanium-alloy modular implants in cementless total hip arthroplasty were investigated. The implants were in service for a period ranging from 18 to 36 months. Two were fractured in vivo and the other was retrieved secondary to aseptic loosening after 18 months in service. Macroscopic examination showed close topographical similarities between the two fractured implants. Dark elliptical region on the fractured surface indicated the occurrence of fatigue process accompanied with corrosion (corrosion fatigue). The presence of numerous latent microcracks demonstrates additional embrittlement of implant structure assisted by environment (hydrogen). Light microscopy and scanning electron microscopy confirmed the presence of fretting, pitting, plastic deformation, and stress-induced corrosion cracking. Two implants (Cases I and II) fractured in identical way, while the third modular implant subjected to lower loads did not exhibit fracture, but it exhibited significant Al release. Taper performance is influenced by metallurgy, the load carried and the effect of the local microenvironment. Methods to reduce the impact of these factors may reduce the incidence of taper related failure. 相似文献
954.
The National Cancer Institute has collected a large database of uterine cervix images termed “cervigrams”, for cervical cancer screening research. Tissues of interest within the cervigram, in particular the lesions, are of varying sizes and of complexnon-convex shapes. The tissues possess similar color features and their boundaries are not always clear. The main objective of the current work is to provide a segmentation framework for tissues of interest within the cervix, that can cope with these difficulties in an unsupervised manner and with a minimal number of parameters. 相似文献
955.
Understanding and managing the risks inherent to the introduction of a new technology in the highly capital-intensive, large volume, and low-margin steel industry, is a key to effectively implementing a lasting change. New technology risk can be mitigated by recognizing the hierarchy of critical decisions that must be made, whether for a green-field project or a brown-field project that is focused on restructuring and modernizing existing facilities. This leads to a logical sequence of project planning activities starting with an evaluation of technology, its maturity/performance, and scale-up factors, selection of appropriate technologies and plant concepts, development of capital and operating costs, risk evaluation/management strategy, recruiting the best resources and management team, effective pilot and demonstration plant operations that leads to a successful commercial facility. Over the years, Hatch has developed a robust methodology for process technology selection for the iron and steel industry. In particular, this methodology has been successfully applied in the selection of alternate ironmaking technologies, many of which are in different stages of development/implementation. The methodology is based on a two-stage approach in which the first stage includes a preliminary evaluation of all available ironmaking technologies followed by short-listing of the best (maximum 3–4) candidate technologies based on results of mass and energy balance modelling, and a simple financial analysis consisting of payback period, factored capital cost and operating cost estimates as well as risk analysis. The second stage involves a more detailed analysis using refined input data, mass and energy balance, capital and operating cost estimate, as well as a detailed financial analysis of the best technologies selected. The detailed financial evaluation is based on estimation of IRR/NPV and discounted cash flow analyses. This methodology will be quite useful to the Indian iron and steel industry for their future expansion plans considering available input raw materials, fuels and reductants as well as accounting for the quality of the materials. To illustrate the critical elements of this methodology and the analysis required for the successful selection of ironmaking process technology, a case study covering the evaluation and selection of the best (most-suitable) ironmaking technologies for an Iron and Steel Company that is located in the European part of Russian Federation, is presented in this paper. In this study, the selection process considered the steel company’s access to specific input raw materials, reductants as well as fuels. The input materials considered in this analysis present a number of interesting points that are relevant for the Indian steel industry. 相似文献
956.
957.
Post-slaughter changes in ATP metabolites,reducing and phosphorylated sugars in chicken meat 总被引:1,自引:0,他引:1
The formation of ATP breakdown products in chicken M. pectoralis major post-slaughter is reported. The concentrations of metabolites were followed in chicken breast throughout the carcass processing post-slaughter and during chilled storage. The concentration of glucose remains similar throughout the period whilst that of glucose-6-phosphate decreases linearly. Glucose and glucose-6-phosphate concentrations were inversely related to the pHu of the breast meat throughout chilled storage. Rapid post-mortem glycolysis and high pHu values suggest the occurrence of stress at and pre-slaughter. Whilst ATP, ADP and AMP were rapidly broken down, the concentration of IMP rose rapidly and remained high. Concentrations of inosine, ribose and hypoxanthine increased gradually post-slaughter but an initial increase in ribose phosphate was not sustained. Most of the potential ribose present in chicken meat, believed to be important for flavor formation, remains bound in the form of inosine and IMP. There is evidence that additional breakdown pathways for ribose and ribose-5-phosphate may deplete the concentrations of these precursors. 相似文献
958.
959.
An overview of formation and roles of acetaldehyde in winemaking with emphasis on microbiological implications 总被引:6,自引:0,他引:6
Shao-Quan Liu & Gordon J. Pilone 《International Journal of Food Science & Technology》2000,35(1):49-61
Summary Acetaldehyde is an important aroma compound in wine. This article first reviews the microbial and chemical formation of acetaldehyde, then the effects of sulphur dioxide on acetaldehyde and effects of acetaldehyde on wine colour and physical stability are described briefly. Finally, the microbiological implications of acetaldehyde are emphasized with respect to practical significance in wine fermentation. 相似文献
960.
Evgenij A. Popov Alexander A. Pelmenev Eugene B. Gordon 《Journal of Low Temperature Physics》2000,119(3-4):367-376
Thermal diffusivity of the Kr- and N2-impurity-helium solids (IHS) has been measured for the samples, immersed into liquid helium in the temperature range of 2.2–4.2 K. It has been found that the thermal diffusivity for both solids does not differ from that of liquid helium when the convection is absent even for the case when the samples were compact 10 times as compared to their initial volume. It should be emphasized that the presence of less than 0.5% mole fraction of a rare gas in the form of IHS allows us to suppress completely any convection in liquid helium (this effect was not observed when deuterium was used as an impurity). IHS can be used as a specific porous medium for investigations of critical phenomena of the He-I–He-II phase transition, as the He-aerogel systems. 相似文献