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101.
Ten genotypes, cultivated and wild of Cynara cardunculus L. were evaluated for their content of phenolic acids, flavonoids and their antioxidant activity. The major compounds present in the leaf were luteolin derivatives in globe artichoke and apigenin derivatives in wild and cultivated cardoon. Apart from ‘Cimiciusa di Mazzarino’ (var. scolymus), caffeoylquinic acids represent the main phenolic compounds in the floral stem. In particular, ‘Sylvestris Creta’ (var. sylvestris) and ‘Violetto di Sicilia’ (var. scolymus) show the highest content of caffeoylquinic acid ∼95% of the total measured polyphenols. The antioxidant capacity, in both leaf and floral stem, was qualitatively and quantitatively dependent on the phenolic acid and flavonoid profile. The phenolic acids and flavonoids in normally uneaten parts of wild and cultivated artichoke could be exploited as sources of natural antioxidants. 相似文献
102.
Christopher H. Braithwaite Jiri Pachman Jiri Majzlik David M. Williamson 《Propellants, Explosives, Pyrotechnics》2012,37(5):614-620
A series of gap‐test experiments were conducted in accordance with the EMTAP Test 22a guidelines to characterize the stress output from a donor charge of ROWANEX 3601. Forty eight successful gap‐tests were conducted at the University of Pardubice in addition to two supporting plate impact experiments performed at the Cavendish Laboratory, University of Cambridge. The experiments indicated that there are two principal release mechanisms, which produce the observed reduction in stress with increasing gap distance. The first is attenuation of the input wave, something which is expected during explosive loading due to the triangular nature of the loading pulse. The second is an interaction between the input wave and lateral release waves from the edges of the test sample at the measurement station. Attenuation of the input wave due to visco‐elastic loss in the PMMA “gap” used is likely to be less significant than these other two release mechanisms. The data generated by this investigation forms a robust dataset that gives an accurate calibration for ROWANEX 3601 for users of the EMTAP 22a test procedure. In addition the data represent an excellent “set problem” for those developing and wishing to validate, computational models of similar physical phenomena. 相似文献
103.
The effects of the thaumasite form of sulfate attack on skin friction at the concrete/clay interface
The paper presents the effects of thaumasite sulfate attack (TSA) on skin friction at the concrete/clay interface. Using clay-restrained conditions thaumasite formed attached to the concrete culminating in thaumasite layers of up to 24 mm depending on interface pH and applied pressure. Thaumasite at the interface did not decrease the shear strength including skin friction and cohesion. Therefore it was concluded that TSA occurring at piles or foundation bases does not affect the stability of the superstructure regarding loss of friction and settlements. 相似文献
104.
105.
This objective of this work was to develop, test and optimise the design of a novel gas-fired radiant burner suitable for incorporation into industrial tunnel ovens. Computational fluid dynamics (CFD) simulations have been used to model the burner and baking chamber environment, and in particular to predict radiation heat fluxes incident on the top surface of the food, both across the width of the baking chamber and along its length. Data from thermocouple sensors attached to a full-scale 40 kW prototype burner have been used to validate the CFD model. Initial results presented here show that CFD model predictions agree with experimental data to within 10%. CFD simulations have indicated that the new burner is capable of delivering irradiation to a travelling conveyor more uniformly than existing radiant burner designs. The effects of oven chamber humidity and surface emissivity on radiation heat transfer have been quantified. 相似文献
106.
Carbon capture and storage (CCS) is considered a leading technology for reducing CO2 emissions from fossil-fuelled electricity generation plants and could permit the continued use of coal and gas whilst meeting greenhouse gas targets. However considerable energy is required for the capture, compression, transport and storage steps involved. In this paper, energy penalty information in the literature is reviewed, and thermodynamically ideal and “real world” energy penalty values are calculated. For a sub-critical pulverized coal (PC) plant, the energy penalty values for 100% capture are 48.6% and 43.5% for liquefied CO2, and for CO2 compressed to 11 MPa, respectively. When assumptions for supercritical plants were incorporated, results were in broad agreement with published values arising from process modelling. However, we show that energy use in existing capture operations is considerably greater than indicated by most projections. Full CCS demonstration plants are now required to verify modelled energy penalty values. However, it appears unlikely that CCS will deliver significant CO2 reductions in a timely fashion. In addition, many uncertainties remain over the permanence of CO2 storage, either in geological formations, or beneath the ocean. We conclude that further investment in CCS should be seriously questioned by policy makers. 相似文献
107.
A method by which the influence that skin effect in the bars of a cage rotor has on the resistance of the end-rings can be determined numerically is outlined. The method is based on the use of a finite-element model of a portion of the end-ring comprising one rotor slot-pitch and centered on a rotor bar. Numerical results are presented for two particular cage geometries using the data of two commercially manufactured machines. The results indicate that, in machines in which deep-bar effect is important, the consequential changes in rotor end-ring resistance for the fundamental field may be significant. For the harmonics, however, the relatively low magnitude of the end-ring resistance renders deep-bar corrections unnecessary. 相似文献
108.
Abstract: It is estimated that 4.6 billion tons of non‐hazardous solid waste materials are produced annually in the USA. The potential reuse for a portion of the materials in the construction of highways and roads suggests that valuable benefits in terms of economic and environmental gains are possible. This paper describes the development of a prototype computer‐assisted tool or expert system to help manufacturers assess and analyze their industrial residuals as potential road construction material. This represents an expansion in the application of intelligent systems to domains where a few, hard‐to‐find technical reports have represented the main source of expertise available to practitioners for years. The system, developed through the use of an object‐oriented software shell, Level5 Object, was designed in a user‐friendly Windows environment which allows users with little or no computer training to effectively evaluate material residuals. 相似文献
109.
110.
LV Solov'eva MP Svetlova R Hancock R Whittle AR Lehmann D Bootsma NV Tomilin 《Canadian Metallurgical Quarterly》1996,38(12):1294-1302
An auxiliary protein of DNA polymerases delta and epsilon, the proliferating cell nuclear antigen (PCNA), is necessary for efficient DNA replication in vivo and in vitro, and also for the repair synthesis in vitro, but its role in the excision repair of genome in vivo is not exactly established. In S-phase of unirradiated cells, PCNA is tightly bound to focal centers of DNA replication and is not removed by treatment with detergent Triton X-100, but is completely extracted from non-S-phase cells by the indicated detergent. It was shown earlier that after UV-irradiation PCNA could not be removed by the detergent even from non-S-phase cells. It was interpreted as the evidence of PCNA integration into the repair complex and of the participation of this protein in repair synthesis in vivo. In the present work the data were obtained indicating that the role of PCNA in cell response to UV-damage was not confined only to its possible involvement in repair synthesis. With the help of confocal microscopy it was established that in Triton X-100-extracted normal cells PCNA did not colocalize with the well known excision repair protein XPB/ERCC3, defective in cells from Xeroderma pigmentosum (complementation group B) patients. XPB-protein is induced by UV-irradiation in normal cells, and this induction is not observed in repair deficient cells. However, in such cells UV-light induces a detergent-resistant form of PCNA, and this form is obviously not connected with repair. It cannot be excluded that a rapid PCNA immobilization immediately after UV-irradiation of cells is needed for the facilitation of photochemical damage bypass during the subsequent replication of genome. 相似文献