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101.
102.
P—SV波和SH波的AVO分析 总被引:8,自引:1,他引:8
周竹生 《石油地球物理勘探》1993,28(4):430-438
地震反射振幅随炮检距变化的规律不仅纵波存在,横波同样也具有与物性参数有关的AVO特征。本文就P-SV波和SH波的AVO分析作了一些基础工作,其步骤与P波相仿,即从Zoeppritz方程出发,经过一系列可允许的简化,最后导出一些有地质地震属性的计算公式。研究结果发现:①利用P-SV波可以得到与SH波完全一样的地震属性;②从这些属性的数学模型可以发现,只要将现有P波的AVO分析软件稍作一些修改,便可用于横波AVO分析。本文一系列的模型演算结果说明,横波AVO是一项有潜力的技术。 相似文献
103.
This paper uses narrative accounts of private gardens in Britain from the Mass-Observation Archive (MO) to explore ideas of landscape, privacy and attachment that emerge from daily practices and routines in these ordinary domestic spaces. We argue for the domestic garden as a vernacular or ordinary landscape that displays tensions between the private and the public nature of home within ambivalent emotional responses. Extended personal narratives offer privileged access to a site of intense engagement and carefully guarded privacy, yet with varying levels of attachment. The garden is a space well described in Britain in its public form but less well known as a private, everyday landscape. In this way a cultural landscape study becomes a contemporary critical geography of an ordinary space. 相似文献
104.
Twambo Hachibamba Linda Dykes Joseph Awika Amanda Minnaar Kwaku G. Duodu 《International Journal of Food Science & Technology》2013,48(12):2638-2649
Consumption of diets rich in phenolic compounds has been associated with reduced risk of chronic diseases. The effect of cooking and simulated gastrointestinal digestion on phenolic compounds and antioxidant properties of two cowpea (Vigna unguiculata) types was determined. Phenolic acids, flavan‐3‐ols and flavonols were the main groups of phenolic compounds identified. Cooking and simulated enzyme digestion of the cooked cowpea samples rendered some phenolics less extractable (possibly by promoting binding with other food components) or more extractable (possibly by release of bound forms). Total phenolic contents and radical scavenging properties of the cowpeas were reduced upon cooking, but increased upon simulated enzyme digestion. Cowpea extracts inhibited human LDL oxidation at a concentration of 2 mg mL?1 possibly due to their phenolic content. Phenolic compounds in cowpea can potentially protect against cardiovascular diseases for which LDL oxidation is a risk factor. 相似文献
105.
Amanda Seemungal Andrea Petróczi Declan P. Naughton 《European Food Research and Technology》2011,233(5):781-789
Several studies have assessed total anti-oxidant activity of wine or individual components in isolation using chemical-based
assays. In this study, a quantitative approach was developed to assess the relative anti-oxidant efficacies of selected red
wine phenolics via peak reduction, using reversed-phase HPLC. Both intact red wine and phenolic standard solutions were challenged
with five oxidant model systems as follows: (1) hydrogen peroxide (H2O2); redox-active metal ions (2) Fe3+ and (3) Cu2+; and the Fenton reagents (4) H2O2 + Fe2+; and (5) H2O2 + Cu+. Treatment with oxidants (1–3) resulted in loss of 47–60% of phenolic standards, which increased to 66–89% for treatment
with the Fenton systems, with quercetin exhibiting the optimal anti-oxidant activity. For intact red wine, treatment with
oxidants (1–3) led to all phenolic compounds being oxidised (27–77% loss), with caffeic acid and quercetin as the most effective
anti-oxidants. For both Fenton systems (4–5), activities in red wine were considerably enhanced for caffeic acid and quercetin,
which exhibited the highest anti-oxidant efficacies with 100% peak reduction, while p-coumaric acid and gallic acid were less effective anti-oxidants with peak reductions of 60–68%. The ranking, facilitated
by this new quantitative approach, allows comparison of the individual efficacies of the anti-oxidants in a complex matrix. 相似文献
106.
Eoin Devereux Amanda Haynes Martin J. Power 《Journal of Housing and the Built Environment》2011,26(2):123-142
By triangulating analyses of content and reception with a focus on production, this article attempts to understand the dynamics
of and underlying reasons for the media stigmatisation of place. The research described contributes to a body of work examining
how mass media and other social forces factor in the creation of negative stereotypes that damage the reputations of the places
in which the poor reside. The overarching framework of understanding, provided by Goffman’s theory of stigma, is complemented
by two further inter-related theoretical approaches, namely Social Exclusion and Political Economy. Combining analyses of
media production (practices), media content (discourses) and audience reception (beliefs, attitudes), we analyse the representation
of one of Ireland’s most deprived public housing estates in the print and broadcast media. Having established the stigmatising
character and impact of national and local media content via this tripartite methodology, we focus on identifying and explaining
the media practices that serve to (re)produce the estate’s ‘spoiled identity’. Our analysis of journalists’ explanations for
these practices identifies the commercial realities, which progressively influence media production, as directly impacting
media producers’ relationships with, and depictions of, poor places. We conclude by examining debates regarding the potential
for rehabilitating a spoiled identity. 相似文献
107.
Chander Shekhar Sharma Amanda Ates Poulson Joseph Kamlesh A. Soni M. Wes Schilling Aaron Kiess 《International Journal of Food Science & Technology》2013,48(7):1410-1415
The efficacy of lauric arginate (LAE) on Salmonella survivability in ground chicken containing 9.8% fat was determined under refrigerated storage. The effect of LAE treatments on total aerobes, pH and objective colour were also assessed in ground chicken. LAE was highly effective against Salmonella in 0.1% peptone with no detectable survivors following treatment with 200 ppm and 400 ppm of LAE. No difference existed (P > 0.05) in the growth of Salmonella and total aerobes after treatment with 200 and 400 ppm of LAE in ground chicken inoculated with a four strain mixture of Salmonella. At these concentrations, LAE did not exhibit any treatment effect on the pH and colour of ground chicken (P > 0.05). In conclusion, although LAE possesses strong inhibitory (P < 0.05) effect against Salmonella in suspension in 0.1% peptone water, no inhibitory (P > 0.05) effect on growth of Salmonella was observed in ground chicken at the currently approved levels of 200 ppm of LAE. 相似文献
108.
Amanda N. Elkins Eric R. Muth Adam W. Hoover Alexander D. Walker Thomas L. Carpenter Fred S. Switzer 《Applied ergonomics》2009,40(6):997-1003
Physiological compliance (PC) refers to the correlation between physiological measures of team members over time. The goals of this study were to examine ways of measuring PC in heart rate variability (HRV) data and the relationship between PC and team performance. Teams were tasked with entering both real and simulated rooms and “shooting” individuals with a weapon and identifying individuals without a weapon. The linear correlation and directional agreement PC methods were shown to be the most sensitive to differences in performance, with greater PC being associated with better performance. The correlation method when applied to a measure of respiratory sinus arrhythmia (RSA) revealed a significant difference between high and low performers (t[8] = −2.31, p = 0.03) and the directional agreement applied to inter-beat-intervals and RSA revealed trend-level differences (t[4.62] = −1.86, p = 0.06 and t[8] = −1.68, p = 0.07). These results suggest that PC may have merit for predicting team performance. 相似文献
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110.