1,638,882 research outputs found
Investigation of Functional-technological Properties of Soya Protein
There was offered and grounded the use of functional technological properties of the soya protein isolate in the technology of oil pasts. It will allows to increase the balance of the oil past composition additionally and will favor the decrease of extracting moisture during the storage term.There was studied the dynamics of a gradient of the limit stress of soya protein: hydrated soya protein, hydrated soya protein with the temperature processing, hydrated soya protein with the preliminary keeping during 24 h, hydrated soya protein with the preliminary keeping during 24 h and temperature processing during 5 min, hydrated soya protein with the preliminary keeping during 24 h and temperature processing during 10 min; hydrated soya protein with the preliminary keeping during 24 h and temperature processing during 15 min.It was established, that the hydrated isolate of soya protein is a plastic system, has enough strength.The limit stress parameter at the variable velocity of deformation of model samples determines optimal technological parameters of preparing the soya isolate: hydromodule – 1: 8, temperature processing – (82±2) °С, process duration 10 min with preliminary keeping during 24 hours.As a result of the studies, there were demonstrated technological parameters of preparing the soya protein isolate for obtaining the oil past by the direct mixing with the oil base
A consolidation process model for film stacking glass/PPS laminates
The applied pressure, processing temperature and holding time influence the\ud
consolidation of thermoplastic laminates. A model to optimise the processing\ud
parameters is proposed. The influence of heating rate, processing temperature and pressure is investigated. Short textile impregnation times, in the order of seconds, are predicted. The model is validated in an experimental programme
A development of an electrical analogue for thermal processing : a thesis presented in partial fulfillment of the requirements for the degree Master of Technology in Biochemistry at Massey University
A. THERMAL PROCESSING IN GENERAL Thermal processing implies application of thermal energy at suitable thermal potential, namely temperature to a reacting system. Thermal effects on chemicals, biochemicals and biological materials have long been recognised. Existence of these effects has been used to the advantages of many industries. Thermal activation of chemical reactions and biochemical reaction constitutes a very fundamental process in chemical and biochemical technology. Polymerisation reactions, hydrolysing reactions, oxidation and reduction reactions are few examples of many important processing reactions which may involve thermal processing. In active living tissue, many metabolic reactions can proceed appreciably at room temperature, causing undesirable alteration in the tissue. Low temperature storage has the basic objective of arresting the various reactions which may cause spoilage and which proceed at higher temperatures. With active proteins like enzymes and living tissue, denaturation and functional inactivation can occur rapidly at processing temperatures. Sterilization of microorganisms, pasteurisation of milk are specific examples of this type of thermal processing
Temperature and time-dependent effects of delayed blood processing on oxylipin concentrations in human plasma.
BACKGROUND:Oxidized derivatives of polyunsaturated fatty acids, collectively known as oxylipins, are labile bioactive mediators with diverse roles in human physiology and pathology. Oxylipins are increasingly being measured in plasma collected in clinical studies to investigate biological mechanisms and as pharmacodynamic biomarkers for nutrient-based and drug-based interventions. Whole blood is generally stored either on ice or at room temperature prior to processing. However, the potential impacts of delays in processing, and of temperature prior to processing, on oxylipin concentrations are incompletely understood. OBJECTIVE:To evaluate the effects of delayed processing of blood samples in a timeframe that is typical of a clinical laboratory setting, using typical storage temperatures, on concentrations of representative unesterified oxylipins measured by liquid chromatography-tandem mass spectrometry. DESIGN:Whole blood (drawn on three separate occasions from a single person) was collected into 5 mL purple-top potassium-EDTA tubes and stored for 0, 10, 20, 30, 60 or 120 min at room temperature or on wet ice, followed by centrifugation at 4 °C for 10 min with plasma collection. Each sample was run in duplicate, therefore there were six tubes and up to six data points at each time point for each oxylipin at each condition (ice/room temperature). Representative oxylipins derived from arachidonic acid, docosahexaenoic acid, and linoleic acid were quantified by liquid chromatography tandem mass spectrometry. Longitudinal models were used to estimate differences between temperature groups 2 h after blood draw. RESULTS:We found that most oxylipins measured in human plasma in traditional potassium-EDTA tubes are reasonably stable when stored on ice for up to 2 h prior to processing, with little evidence of auto-oxidation in either condition. By contrast, in whole blood stored at room temperature, substantial time-dependent increases in the 12-lipoxygenase-derived (12-HETE, 14-HDHA) and platelet-derived (thromboxane B2) oxylipins were observed. CONCLUSION:These findings suggest that certain plasma oxylipins can be measured with reasonable accuracy despite delayed processing for up to 2 h when blood is stored on ice prior to centrifugation. 12-Lipoxygenase- and platelet-derived oxylipins may be particularly sensitive to post-collection artifact with delayed processing at room temperature. Future studies are needed to determine impacts of duration and temperature of centrifugation on oxylipin concentrations
Accelerating Dust Temperature Calculations with Graphics Processing Units
When calculating the infrared spectral energy distributions (SEDs) of
galaxies in radiation-transfer models, the calculation of dust grain
temperatures is generally the most time-consuming part of the calculation.
Because of its highly parallel nature, this calculation is perfectly suited for
massively parallel general-purpose Graphics Processing Units (GPUs). This paper
presents an implementation of the calculation of dust grain equilibrium
temperatures on GPUs in the Monte-Carlo radiation transfer code Sunrise, using
the CUDA API. The GPU can perform this calculation 69 times faster than the 8
CPU cores, showing great potential for accelerating calculations of galaxy
SEDs.Comment: 7 pages, 2 figures, accepted to New Astronomy. Minor updates to text
and performance based on feedback from refere
Highly processable bulk metallic glass-forming alloys in the Pt–Co–Ni–Cu–P system
Highly processable bulk metallic glass alloys in the Pt–Co–Ni–Cu–P system were discovered. The alloys show low liquidus temperature below 900 K, excellent processability with low critical cooling rate reflecting in maximum casting thicknesses in quartz tubes of up to 20 mm, and a large supercooled liquid region. The Pt57.5Cu14.7Ni5.3P22.5 composition has a liquidus temperature of 795 K, a glass transition temperature of 508 K with a supercooled liquid region of 98 K. For medical and jewelry applications a Ni-free alloy, Pt60Cu16Co2P22 was discovered with a liquidus temperature of 881 K, a glass transition temperature of 506 K, and a supercooled liquid region of 63 K. Glass formation was observed in a wider composition range. Vickers hardness of these alloys is in the 400 Hv range. The alloys can be processed in the supercooled liquid region in air without any measurable oxidation. In this region, a large processing window is available in which the material does not embrittle. Embrittlement in these alloys is correlated with crystallization. It can be avoided as long as substantial crystallization does not take place during isothermal processing in the supercooled liquid region. Also, liquid processing can be performed in air when flux with B2O3
Quartz crystal microbalances to measure wind velocity and air humidity
Instrument includes four temperature-sensing, Y-cut quartz crystals to determine wind direction, velocity, and temperature. Two additional AT-cut crystals are used to determine air humidity. Entire signal processing is provided by built-in electronics circuits
Variable retort temperature optimization benefit in scheduling for retorts of different capacities in food canneries
In the majority of small- to medium-sized canneries, retorting is carried out in a battery of retorts as a batch process. For such canneries, the unloading and reloading operations for each retort are labor-intensive; therefore, a well-designed and well-managed plant should be utilized in order to optimize the whole sterilization process. In other words, it is necessary to develop a suitable mathematical model for the operation of the whole plant and to determine the optimal values of its decision variables. The result of such a model involves the quantities of each product to be loaded onto the retorts for each of the batches, and the optimal solution provides an optimum scheduling. On the other hand, it is well-known that variable retort temperature processing can be used for reducing the sterilization processing time required for sterilization using the traditional constant retort temperature processing. Therefore, the objective of this research consisted of utilizing a variable retort temperature processing in developing a mathematical model for scheduling at food canneries for the case of retorts of different capacities. The developed model was based on mixed-integer linear programming and simultaneous sterilization based on variable retort temperature processing. The adaptive random search algorithm coupled with penalty functions approach, and the finite difference method with cubic spline approximation are utilized in this study to obtain the simultaneous sterilization vectors to be processed under time-variable retort temperature. The proposed in this study methodology can be useful for small- and medium-sized food canneries, which work with many different products simultaneously
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High-temperature chemical processing on asteroids: An oxygen isotope perspective
From the introduction: Small planetary bodies accreted within 2.4 Myr of solar system formation [1]. The primitive materials (CAIs, chondrules, matrix) incorporated into these asteroids were altered by a variety of secondary processes, including aqueous alteration, shock metamorphism, thermal metamorphism and melting. Here we look primarily at the role played by thermal metamorphism and melting in altering the oxygen isotope systematics of asteroidal materials
Thermal food processing computation software
The objective of this research consisted of developing the two following thermal food processing software: “F-CALC” is software developed to carry out thermal process calculations based on the well-known Ball's formula method, and “OPT-PROx” is software for thermal food processing optimization based on variable retort temperature processing and global optimization technique. Time-temperature data loaded from Excel-file is used by “F-CALC” software to evaluate the heat penetration parameters jh and fh, as well as to compute process lethality for given process time or vice versa. The possibility of computing the process time and lethality for broken heating curves is included. The diversity of thermal food processing optimization problems with different objectives and required constraints are solvable by “OPT-PROx” software. The adaptive random search algorithm coupled with penalty functions approach, and the finite difference method with cubic spline approximation are utilized by “OPT-PROx” for simulation and optimization thermal food processes. The possibility of estimating the thermal diffusivity coefficient based on the mean squared error function minimization is included. The “OPT-PROx” software was successfully tested on the real thermal food processing problems, namely in the case of total process time minimization with a constraint for average and surface retentions the “OPT-PROx” demonstrates significant advantage over the traditional constant temperature processes in terms of process time and final product quality. The developed user friendly dialogue and used numerical procedures make the “F-CALC” and “OPT-PROx” software extremely useful for food scientists (research and education) and engineers (real thermal food process evaluation and optimization)
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