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1.
A standard method for the extraction of tiger nut milk has been introduced. It has been shown that, although milling duration improves the yield of tiger nut milk solids and its nutrient composition, there is a quantifiable loss of nutrient in the pressing residue during milk extraction. Milling duration improved the colloidal stability of the milk against creaming during 16 h of storage. A higher milling intensity resulted in the aggregation of biological polymers which resulted in colloidal destabilisation. Milling improved the lightness and stability and reduced browning rate of the tiger nut milk during storage. This report is important for the production of tiger nut milk of consistent and comparable characteristics. Milling has been introduced as a processing method for the qualitative and quantitative modulation of the properties of tiger nut milk. It is recommended to develop further strategies to improve the colloidal stability of tiger nut milk as a beverage.  相似文献   
2.
The dehydroalkylation of toluene with ethane to the isomeric ethyltoluenes was studied on 0.4Pt/H-ZSM-5 at varying contact times (1/WHSV). At a high contact time of 1.0 h, toluene disproportionation and hydrogenolysis reactions dominate, resulting in low selectivity to the desired ethyltoluenes via the alkylation reaction. However, at a low contact time of 0.12 h side reactions are eliminated, resulting in maximum selectivities to the kinetically favored ethyltoluenes and hydrogen. Results at high selectivities to ethyltoluenes provide significant insight into reaction pathways.  相似文献   
3.
A novel, unobtrusive and wearable, multiparameter ambulatory physiologic monitoring system for space and terrestrial applications, termed LifeGuard, is presented. The core element is a wearable monitor, the crew physiologic observation device (CPOD), that provides the capability to continuously record two standard electrocardiogram leads, respiration rate via impedance plethysmography, heart rate, hemoglobin oxygen saturation, ambient or body temperature, three axes of acceleration, and blood pressure. These parameters can be digitally recorded with high fidelity over a 9-h period with precise time stamps and user-defined event markers. Data can be continuously streamed to a base station using a built-in Bluetooth RF link or stored in 32 MB of on-board flash memory and downloaded to a personal computer using a serial port. The device is powered by two AAA batteries. The design, laboratory, and field testing of the wearable monitors are described.  相似文献   
4.
In this paper, we will discuss a methodology developed and applied in the European ITERATE project with the objective of designing experiments that will provide data to seed the numerical model of operator behaviour in different surface transport modes: road vehicles, rail transport and ships. The experiments aim to investigate how new technologies support different types of operators in different contexts. A structured approach was adopted. Firstly, an initial selection of the systems to be investigated was made, describing the support they provide for operators. Hypotheses were formulated on the effects of operator parameters on the interaction with the systems. A final selection of systems for the experiments was made, focusing on systems providing support for collision avoidance and speed management. The operator parameters (culture, attitude and personality, experience, driver state (such as fatigue) and the demands of the task) were operationalised and piloted. The next step was the development of scenarios to be implemented in a driving simulator. In the last step, the final experiments were designed and detailed.  相似文献   
5.
The virtue of the so-called ‘proline concept’ andthe ‘charge concept’ for stabilizing protease-susceptibleregions of a protein structure was compared on bovine pancreaticribonuclease A. Alanine 20 and serine 21, both of whichare located in a loop that is susceptible to the unspecificproteases subtilisin Carlsberg, subtilisin BPN', proteinaseK and elastase, were replaced with proline or lysine by site-directedmutagenesis. The rate constant of proteolysis was decreasedby up to three orders of magnitude for the proline mutants dependingon the site of the mutation and the protease used. In contrast,substitution by lysine increased the proteolytic resistanceby only one order of magnitude characterizing the ‘prolineconcept’ as superior to the ‘charge concept’.Although the four applied proteases are considered to be unspecific,the degree of stabilization of the ribonuclease molecule variedconsiderably, indicating the impact of individual differencesin their substrate specificity on the proteolytic resistanceand degradation pathway of the target protein. Received May 12, 2003; revised October 23, 2003; accepted October 30, 2003  相似文献   
6.
Organic solvent nanofiltration (OSN) is gradually expanding from academic research to industrial implementation. The need for membranes with low and sharp molecular weight cutoffs that are able to operate under aggressive OSN conditions is increasing. However, the lack of comparable and uniform performance data frustrates the screening and membrane selection for processes. Here, a collaboration is presented between several academic and industrial partners analyzing the separation performance of 10 different membranes using three model process mixtures. Membrane materials range from classic polymeric and thin film composites (TFCs) to hybrid ceramic types. The model solutions were chosen to mimic cases relevant to today's industrial use: relatively low molar mass solutes (330–550 Da) in n-heptane, toluene, and anisole.  相似文献   
7.
8.
Software architecture has been established in software engineering for almost 40 years. When developing and evolving software products, architecture is expected to be even more relevant compared to contract development. However, the research results seem not to have influenced the development practice around software products very much. The architecture often only exists implicitly in discussions that accompany the development. Nonetheless many of the software products have been used for over 10, or even 20 years. How do development teams manage to accommodate changing needs and at the same time maintain the quality of the product? In order to answer this question, grounded theory study based on 15 semi-structured interviews was conducted in order to find out about the wide spectrum of architecture practices in software product developing organisations. Our results indicate that a chief architect or central developer acts as a ‘walking architecture’ devising changes and discussing local designs while at the same time updating his own knowledge about problematic aspects that need to be addressed. Architecture documentation and representations might not be used, especially if they replace the feedback from on-going developments into the ‘architecturing’ practices. Referring to results from Computer Supported Cooperative Work, we discuss how explicating the existing architecture needs to be complemented by social protocols to support the communication and knowledge sharing processes of the ‘walking architecture’.  相似文献   
9.
We show how the study of the geometry of the nine flex tangents to a cubic produces pseudo-parameterizations, including the ones given by Icart, Kammerer, Lercier, Renault and Farashahi, and infinitely many new ones.  相似文献   
10.
Based on a qualitative study of the Stoner-Wohlfarth model, we point out that driving a magnetic tunnel junction (MTJ) with an alternative two-dimensional magnetic field allows to measure simultaneously two components of an external magnetic field. Only one single MTJ without a pinning layer is needed to measure both components of a magnetic field parallel to the junction plane. The response of the magnetometer does not depend on the resistance of the junction or the amplitude of its variations. A prototype has been manufactured and encouraging experimental results are presented. Sensitivities higher than 500 V/T and a noise level of 2 /spl mu/T//spl radic/Hz are reported.  相似文献   
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