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991.
Muhammad Gulzar Valérie Lechevalier Saïd Bouhallab Thomas Croguennec 《Journal of food engineering》2012
In this study we determined the composition (proportion of native proteins, soluble and insoluble aggregates) and quantified the gelling properties (gel strength and water holding capacity) of pre-texturized whey proteins by dry heating under controlled physicochemical conditions. For this purpose, a commercial whey protein isolate was dry heated at 80 °C (up to 6 days), 100 °C (up to 24 h) and 120 °C (up to 3 h) under controlled pH (2.5, 4.5 or 6.5) and water activity (0.23, 0.32, or 0.52). Gelling properties were quantified on heat-set gels prepared from reconstituted pre-texturized proteins at 10% and pH 7.0. The formation of dry-heat soluble aggregates enhanced the gelling properties of whey proteins. The maximal gelling properties was achieved earlier by increasing pH and water activity of powders subjected to dry heating. An optimized combination of the dry heating parameters will help to achieve better gelling properties for dry heated whey proteins. 相似文献
992.
Dr. Sebastian Meier Dr. Natalia Solodovnikova Dr. Pernille R. Jensen Prof. Jürgen Wendland 《Chembiochem : a European journal of chemical biology》2012,13(15):2265-2269
Detecting the molecular targets of xenobiotic substances in vivo poses a considerable analytical challenge. Here, we describe the use of an NMR‐based tracer methodology for the instantaneous in vivo observation of sulfur(IV) action on cellular metabolism. Specifically, we find that glycolytic flux is directed towards sulfite adducts of dihydroxyacetone phosphate and pyruvate as off‐pathway intermediates that obstruct glycolytic flux. In particular, the pyruvate–sulfite association hinders the formation of downstream metabolites. The apparent in vivo association constant of pyruvate and sulfite agrees with the apparent inhibition constant of CO2 formation, thus supporting the importance of pyruvate interception in disturbing central metabolism and inhibiting NAD regeneration. 相似文献
993.
Thomas Blacha Massimiliano Di Domenico Peter Gerlinger Manfred Aigner 《Combustion and Flame》2012,159(1):181-193
A new soot model is presented, which has been developed for CFD applications, combining accuracy and efficiency. While the chemical reactions of small gas phase species are captured by a detailed chemical kinetic mechanism, polycyclic aromatic hydrocarbons (PAHs) and soot particles are represented by sectional approaches. The latter account for important mechanisms such as the formation of sections, their oxidation, the condensation of acetylene, and the collisions between sections. The model has been designed to predict soot for a variety of fuels with good accuracy at relatively low computational cost. Universal model parameters are applied, which require no tuning in dependence of test case or fuel. Soot predictions of ethylene, propylene, kerosene surrogate, and toluene flames are presented, which show good agreement with the experimental data. Furthermore, the importance of the correct choice for thermodynamic data of PAHs and soot is highlighted and the impact of heat radiation is discussed. 相似文献
994.
Timothy Rumbell John Barnden Susan Denham Thomas Wennekers 《Autonomous Agents and Multi-Agent Systems》2012,25(1):1-45
Emotion mechanisms are often used in artificial agents as a method of improving action selection. Comparisons between agents
are difficult due to a lack of unity between the theories of emotion, tasks of agents and types of action selection utilised.
A set of architectural qualities is proposed as a basis for making comparisons between agents. An analysis of existing agent
architectures that include an emotion mechanism can help to triangulate design possibilities within the space outlined by
these qualities. With this in mind, twelve autonomous agents incorporating an emotion mechanism into action selection are
selected for analysis. Each agent is dissected using these architectural qualities (the agent architecture, the action selection
mechanism, the emotion mechanism and emotion state representation, along with the emotion model it is based on). This helps
to place the agents within an architectural space, highlights contrasting methods of implementing similar theoretical components,
and suggests which architectural aspects are important to performance of tasks. An initial framework is introduced, consisting
of a series of recommendations for designing emotion mechanisms within artificial agents, based on correlations between emotion
roles performed and the aspects of emotion mechanisms used to perform those roles. The conclusion discusses how problems with
this type of research can be resolved and to what extent development of a framework can aid future research. 相似文献
995.
Krishnendu Chatterjee Thomas A. Henzinger 《Journal of Computer and System Sciences》2012,78(2):394-413
We summarize classical and recent results about two-player games played on graphs with ω-regular objectives. These games have applications in the verification and synthesis of reactive systems. Important distinctions are whether a graph game is turn-based or concurrent; deterministic or stochastic; zero-sum or not. We cluster known results and open problems according to these classifications. 相似文献
996.
Experimental study on the time‐dependent smoke densities at 39 locations in a multi‐floor building through a digital smoke detector system
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The objective of this study was to quantitatively investigate some characteristics of the smoke transportation in multi‐floor buildings. Eight experiments were conducted for worst scenario. The effects of an open window in the burning room on the smoke transportation are also analyzed. The time‐dependent smoke densities at 39 locations in a half‐scale building with an atrium were measured through a digital smoke detector system. The results indicate that the chimney effect plays an important role in the smoke transportation in multi‐floor buildings with atriums. For the effects of the open window, the results suggest that the smoke densities at most locations in the building increase earlier when a window is open but have a smaller peak value than those results in the cases without any outer vents. It is suggested that a building without vertical atrium would be safer than those with long ones. More attention should be paid to those spaces when the fire protection systems are designed for buildings with atriums. The data of the time‐dependent smoke densities at tens of locations in the building are useful for the validation of smoke transportation models. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
997.
S.L. Ashok Kumar M. Saravana Kumar R.P. John P. Thomas Muthiah A. Sreekanth 《Materials science & engineering. C, Materials for biological applications》2013,33(5):2519-2525
1,5-Bis (2-hydroxyacetophenone)thiocarbohydrazone (H4L) has been synthesized and characterized by means of spectroscopic and single crystal X-ray diffraction methods. Interactions of the H4L with a variety of anions were investigated using a combination of UV–visible and fluorescence spectroscopic methods in a biological competing solvent DMSO. The H4L has a high degree of selectivity for fluoride over other anions. 1H NMR titration experiments indicate that a deprotonation process is involved in the chemo sensing process. 相似文献
998.
999.
René Köppel Thomas Bucher Alain Meuwly Dominik Moor 《European Food Research and Technology》2014,239(2):347-355
According to the release of authorization, several new transgenic soy crops are expected to be present in the harvest of soy beans. In contrast to earlier times, methods for the detection of these transgenic crops are available already in advance. However, these methods are mainly still inefficient single real-time PCR methods. To increase the efficiency of product control, a multiplex quantitative real-time PCR system was developed and characterized for the four new transgenic soy traits DP-356043-5, DP-305423-1, MON 87701 and BPS-CV127-9. It showed amplification efficiency, correlation and sensitivity similar to the single PCR systems applied therein. To evaluate the robustness, an appropriate testing scheme was developed and applied for the first time on this multiplex real-time PCR system. It showed the robust amplification of all analytes also in case where conditions were varied. This system allows relative multiplex quantification and/or delta–delta Ct method quantification and proofed the applicability in routine. 相似文献
1000.
Photonic Nanostructures Patterned by Thermal Nanoimprint Directly into Organo‐Metal Halide Perovskites
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