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21.
Anthony L. Whitear 《Journal of the Institute of Brewing》1991,97(1):47-51
Laurence Bishop's contribution to the brewing industry over more than 50 years of research endeavour and committee activities is reviewed. Three research areas — prediction of extract, the effect of turbidity on yeast activity during fermentation and the development of a 3-vessel fermentation system — are used to highlight his achievements. Five topics with which the author was intimately involved, three of which were connected with Laurence Bishop's own researches, are used to describe the author's activities. These concerned the assessment of beer foam, the prediction of beer stability, the assessment of the bittering value of hops, time course changes in the analytical characteristic of an ale fermentation and the use of fractional factorial designs to facilitate experimental programmes. 相似文献
22.
Crabbe John C.; Gallaher Edward S.; Phillips Tamara J.; Belknap John K. 《Canadian Metallurgical Quarterly》1994,108(1):186
Mice from 15 inbred strains (n?=?27–40 per strain) differed in sensitivity to ethanol-induced effects on open-field activity, hypothermia, rotarod ataxia, and anesthesia. Sensitivities to the different behavioral responses were generally uncorrelated. This suggests that the genetic determinants of behavioral sensitivity to one domain of ethanol effects are unrelated to those determining other responses. On the other hand, some variables were genetically related. For example, those strains sensitive to the loss of righting reflex induced by higher doses of ethanol showed reduced activity in the open field at lower doses and were more sensitive to ethanol-induced decreases in rearing. More generally, the pattern of results suggests that genetically influenced sensitivity to ethanol is not a monolithic phenomenon. Rather, it is specific to the particular response variable studied. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
Gradient-corrected density functional theory was used to investigate the adsorption of H2S on Pd(1 1 1) surface. Molecular adsorption was found to be stable with H2S binding preferentially at top sites. In addition, the adsorption of other S moieties (SH and S) was investigated. SH and S were found to be preferentially bind at the bridge and fcc sites, respectively. The reaction pathways and energy profiles for H2S decomposition giving rise to adsorbed S and H were determined. Both H2S(ad) → SH(ad) + H(ad) and SH(ad) → S(ad) + H(ad) reactions were found to have low barriers and high exothermicities. This reveals that the decomposition of H2S on Pd(1 1 1) surface is a facile process. 相似文献
24.
Anthony L. Andrady Carlos M. Nunez Bor‐Sen Chiou Saad A. Khan 《Polymer Engineering and Science》2002,42(11):2065-2071
The solution rheology of different generations of hyperbranched polyesters in N‐methyl‐2‐pyrrolidinone (NMP) solvent was examined in this study. The solutions exhibited Newtonian behavior over a wide range of polyester concentrations. Also, the relative viscosities of poly(amidoamine) (PAMAM) dendrimers in ethylenediamine were compared with those of the hyperbranched polyesters in NMP. Both types of dendritic polymers have relative viscosities that are exponential functions of their molar fraction in solution. The slopes of these relative viscosity curves show a linear relationship with respect to the generation number. PAMAM dendrimers have the greater slopes for each generation, reflecting their relatively larger intrinsic viscosity values. 相似文献
25.
26.
This paper mainly focuses on the influence of three kinds of media: air, air-10%PA (Nylon) and air-10% POM (polyoxymethylene) on low-voltage circuit breaker arcs. A threedimensional (3-D) model of arc motioa under the effect of external magnetic field is built based on magnetohydrodynamics (MHD) equations. By adopting the commercial computational fluid dynamics (CFD) package based on the control-volume method, the above MHD equations are solved. For the media of air-10%PA and air-10%POM, the distributions of stationary temperature and electrical potential and the transient motion processes are compared with those of air arc. The research shows that both air-10%PA and air -10% POM can cool the arc plasma and the former is more effective. Both of them can increase the stationary voltage as well. Moreover, the presence of the two mixtures can accelerate the arc motion toward the quenching area and ensures the arc quenched in time. 相似文献
27.
e-Government systems differ from commercial information systems (IS) in that they frequently encompass strategic goals that go beyond efficiency, effectiveness and economy, and include political and social objectives such as trust in government, social inclusion, community regeneration, community well-being and sustainability. Designing e-Government systems that help to meet these objectives is a significant challenge for the future. This paper develops an evaluative design framework for e-Government projects that complements traditional approaches to IS evaluation. The framework is based upon Moor's concept of public value. It focuses upon citizens' and clients' experiences of service provision and service outcomes as contributors to the formation of public trust. Trust is shown to be related to the extent to which people feel that an e-Government service enhances their sense of being well-informed, gives them greater personal control, and provides them with a sense of influence or contingency. The framework's development and validation are founded upon analyses of a two live case studies in south-east England and London, U.K. 相似文献
28.
In this paper we study the performance of direction-finding systems which attempt to estimate unknown array parameters (such as sensor gains and phases) in addition to the estimation of the directions of arrival (DOA), as a way of performing array self-calibration. We develop compact closed form expressions for the Cramér-Rao bound associated with the joint estimation of DOAs, gains, phases, and the signal covariance matrix. By evaluating the Cramér-Rao bound for selected cases we gain some insight into the performance of direction-finding systems in the presence of gain and phase uncertainties.This work was supported by the Army Research Office under Contract No. DAAL03-89-C-0007, sponsored by U.S. Army Communications Electronics Command, Center for Signals Warfare. 相似文献
29.
MD Medlock JR Madsen PD Barnes DS Anthony LE Cohen RM Scott 《Canadian Metallurgical Quarterly》1997,27(3):121-128
There are many in vivo animal models for studying airway mucus secretion and hypersecretion, each with advantages and disadvantages. Use of a particular test system will depend upon the aspect of secretion to be modelled. Airway hypersecretory diseases exhibit chronic mucus hypersecretion, of which the clinical impact is predominantly in the distal airways. The majority of documented test preparations study acute secretion, invariably using tracheal preparations, but have been invaluable in elucidating the normal physiology of airway mucus secretion. Chronic models of the hypersecretory state in the distal airways have been developed, but are predominantly histologic in nature (for example quantification of increased goblet cell number). There are few investigations of mucus hypersecretion. Examination of the 'antisecretory' potential of pharmaceutical compounds has been investigated predominantly in chronic histologic models with the drug being given 'prophylactically' rather than 'therapeutically'. Refinement of chronic hypersecretory models should lead to elucidation of the connection between airway irritation, inflammation, MUC gene expression, mucous cell hyperplasia/metaplasia, airway hypersecretion and bronchial hypersecretory disease. 相似文献
30.
A method for the rapid, simultaneous determination of protein, fat, carbohydrate, non-protein nitrogen and total solids in milk and liquid dairy products by infrared reflectance spectroscopy is presented. The method is calibrated against known standards obtained by conventional, time-consuming wet chemical methods but, once calibrated, can be operated routinely by non-skilled personnel. The method is sensitive and accurate down to 0·5% w/v and can be applied to most liquid samples without any need for prior preparation. 相似文献