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1.
Alcohol-free beer with isotonic properties is getting more popular and its production can be carried out by different production strategies; however, interrupted fermentation is still a challenge. Therefore, the objective of this study was to develop a low-alcohol isotonic beer (<0.5% v/v) by interrupted fermentation. Moreover, the major objective is to compare the developed product to commercial beverages (sports drinks, ‘Pilsen' regular beer, alcohol-free beers and low-alcohol isotonic beer). The beverages were evaluated based on pH, alcohol content (% v/v), total titratable acidity (mEq L−1), osmolality (mOsmol kg−1), bitterness International Bitterness Units, colour European Brewery Convention, total phenolic compounds (mg L−1 gallic acid), reducing and total sugars (%) and Na and K contents (mg L−1). The developed low-alcohol isotonic beer presented characteristics similar to sports drinks, with the advantage of being richer in phenolic compounds and suitable osmolality. Despite salts were added in its formulation, the grades attributed to all beers employed in the sensory evaluation, as well as the purchase intention did not present significant differences.  相似文献   
2.
Behaviour of a series of lubricant oils and the effect of a non stoichiometric inorganic compound, as solid extreme pressure additive, on rolling fatigue life are studied using the rolling four-ball accelerated service simulation test proposed by Barwell and Scott. The results show, in all tested cases, the remarkable efficacy of this type of additive. The Total Acidity Number (tan) was found to increase with performance time for the case of the base lubricant, while for the oils with additives, it remained at its constant low value. This led to a proposal of a possible mechanism of the additive performance in the rolling process.  相似文献   
3.
TiO2 sensitization for solar applications requires not only efficient but also stable and inexpensive sensitizers. Different condensed tannins extracted from bark wastes of tropical wood trees were studied as possible sensitizers of TiO2. These natural polymers adhere strongly to the TiO2 even from aqueous solutions. Absorption spectra are presented for 1 mM aqueous sensitizing solutions prepared with lyophilized condensed tannins which absorb light in the visible range. Spectral photocurrent measurements and IV characterization show that no bias is required for electron injection to the TiO2 from all studied condensed tannins. Incident photon to current efficiency (IPCE) analysis indicates that surface complexation originates absorption bands with different electron injection efficiencies. These play a dominant role in determining IPCE spectral shape. We propose that surface modification by the sensitizer changes the surface trap density, thereby decreasing recombination losses.  相似文献   
4.
Due to the unique requirements of a series of projects to specify communications architectures using graphical representations (Cara and MFD), we have developed the communications-oriented rule-based language Carla (Cara Rule Language), which provides an executable specification of the architecture being developed. Carla is designed to provide the ability to specify and simulate high-level, possibly incomplete, specifications of communications architectures, and to allow the developer to refine the specification through the addition of behavior-describing rules. Carla is also well-suited to creating black-box specifications of any system whose behavior depends on input/output history. We describe the features of the language, discuss various design issues, and provide examples of various communications protocols specified in Carla.  相似文献   
5.
Swoop: A Web Ontology Editing Browser   总被引:2,自引:0,他引:2  
In this paper, we describe Swoop, a hypermedia inspired Ontology Browser and Editor based on OWL, the recently standardized Web-oriented ontology language. After discussing the design rationale and architecture of Swoop, we focus mainly on its features, using illustrative examples to highlight its use. We demonstrate that with its Web-metaphor, adherence to OWL recommendations and key unique features, such as Collaborative Annotation using Annotea, Swoop acts as a useful and efficient Web Ontology development tool. We conclude with a list of future plans for Swoop, that should further increase its overall appeal and accessibility.  相似文献   
6.
Systems in which semi-autonomous problem-solving agents communicate and cooperate with one another represent an exciting vision of future computing environments. However, if this vision is ever going to result in commercially viable systems, then consideration must be given to the large software base that exists within many organisations. Success requires the ability to incorporate pre-existing systems alongside purpose-built agents in a cooperating community. This requirement is vital because the former represent a substantial resource investment that companies cannot afford to consign to the scrap heap. We report on our experiences of constructing cooperating communities that contain elements that were pre-existing and some that were developed specifically for incorporation into an integrated environment. The general purpose framework of ARCHON (ARchitecture for Cooperative Heterogeneous ON-line systems) provides the underlying technology to facilitate cooperative problem solving, and the exemplar domain is the real world problem of electricity distribution management. The actual application being developed is called CIDIM (Cooperating Intelligent systems for DIstribution system Management). An evolving methodology for designing and developing a mixed system such as this is outlined, based on our experiences in CIDIM and several other real-world industrial applications. It specifies a hybrid top-down and bottom-up approach to integration, identifies the important characteristics that shape multi-agent problem analysis, and outlines key factors that impinge upon the design of the community. this methodology is then used to motivate the design decisions for the CIDIM application. Finally the process of instantiating the individual agents is discussed, some helpful guidelines on testing and evaluating future applications are given, and the implementation of one of CIDIM's cooperative scenarios is described in depth.  相似文献   
7.
In this brief, we consider methods to improve the performance of chaotic communication schemes. We study a system using a receiver which explicitly includes the presence of noise in the channel. We show how the choice of chaotic dynamical system generating the transmitted signal is crucial. We observe a large variation in bit error rate performance of the system as parameters in the maps are changed, and we propose a simple explanation for this variation.  相似文献   
8.
ROM cell architectures are proposed that have roughly 20% greater storage density in the cell array compared to that of a conventional ROM. Increased density is achieved by exploiting the multiple interconnect layers now available in common logic processes and by using multiple ROM cell types in combination. The storage density of arrays of these hybrid ROM cells increases further as more interconnect layers become available. In addition, a new SRAM-ROM architecture is presented that capitalizes on these techniques to add ROM capability to a conventional SRAM cell with no additional transistors in the memory cell and little or, in some cases, no impact on the cell area  相似文献   
9.
Temporal message-flow diagrams (TMFDs), alternatively called sequence charts, interaction diagrams, event traces, or actor diagrams, are illustrations of a system's global message-passing activity over time, and a pictorial aid to understanding the system's behavior. They are widely used for requirements and documentation for network protocols and object-oriented applications. We present a general formalism for TMFDs, describe a suite of tools we have designed that employs this formalism, and present our experiences with these tools. The formalism and tools described serve to support and broaden the use of TMFDs in developing communicating systems.  相似文献   
10.
C.A. Bernardo  D.L. Trimm 《Carbon》1979,17(2):115-120
The kinetics of gasification of carbon deposited on nickel foils and nickel-alumina catalysts by steam, carbon dioxide and hydrogen are reported for the temperature range 450–850°C. At atmospheric pressure steam is the most effective gasifying agent. In all cases, the kinetic data obtained at lower temperatures (below 600°C) is consistent with control of the process by the chemical reaction. As the temperature increases, the rates of gasification by steam and carbon dioxide are limited by mass transfer effects. The concentration of methane near reaction sites affects the rate of hydrogen gasification above 650°C.  相似文献   
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