Influence of Whey Protein Addition and Feed Moisture Content on Chosen Physicochemical Properties of Directly Expanded Corn Extrudates

Production of extrudates from cereals is an often-used technological process in today’s world food industry. Extrudates from corn flour produced using the twin-screw extrusion process and enriched with whey protein concentrate represent high-quality source of proteins and fats. Whey protein concentrate (WPC) as a valuable source of proteins and minerals is one of the highest-quality components for possible extrudate enrichment. In this paper, the influence of various WPC addition and some extrusion process parameters such as feed moisture content ( Q_{\textH\text2 \textO} Q_{{{\text{H}}_{\text{2}} {\text{O}}}} ) on physicochemical properties of directly expanded corn flour extrudates manufactured in twin-screw co-rotating extruder was investigated. Whey protein concentrate was added in the following ratios 7.5%, 15% and 22.5% and water in 10.08, 12.18 and 14.28 L/h. Final composition of products is determined with measuring of protein, fat and water shares, water absorption index (WAI) and water solubility index (WSI). With added WPC and with increase of water volume flow, there was a significant rise in total protein, fat and water content in final products, as well as lowering of WSI and rising of WAI indexes. The statistical analysis of the obtained data shows that the lowest WSI and the highest WAI had samples with the largest share of WPC (22.5%) and water volume flow of 14.28 L/h. Colour is measured for each sample, and results were represented with hue angle (H), chroma (C) and lightness (L) values. Process parameters, WPC and Q_{\textH\text2 \textO} Q_{{{\text{H}}_{\text{2}} {\text{O}}}} influence the increase of saturation of C and lightness of L colour value, while H value stays unchanged. Mean value of H was 90.14 ± 1.06, which corresponds to dominance of yellow colour of samples.     

Using informal notes for sharing corporate technology know-how

Corporate and academic communities have focused a great deal of attention on formalized approaches for creating, capturing, and propagating knowledge. Far less attention has been paid to the informal mechanisms that individuals share and employ to help them navigate complex processes in order to ‘get things done.’ In this paper, we examine the creation, use, and content of informal documents for supporting users of an enterprise resource planning system in a Fortune 500 company. We contend that such notes, which are commonly used for supporting information systems-related work, are an overlooked source of knowledgeability about organizational practices. This study is a first but necessary step in analyzing the types of information that can be derived from informal notes so that organizations can more fully utilize this largely untapped resource.     

Temperature modeling and measurement of an electrokinetic separation chip

This work presents experimental [infrared (IR) thermography] and computational (finite element model) results of temperature distributions of an electrokinetic separation chip. Thermal characteristics of both the electrolyte solution and the polymer chip (SU-8) are taken into account in modeling temperature distributions during electrokinetic flow. Multiphysics and multiscale simulation couples electrostatics, heat transfer, and fluid dynamics. The accompanying IR thermography is a non-contact method, which can measure fractional temperature differences with sub-second time resolution. Any structures or temperature marker molecules interfering with the experiment are not needed. Nominal spot size in the IR measurements is 30 μm with a field of view of several millimeters enabling both local and chip-scale temperature monitoring simultaneously. As a result, we present a computer model for electrokinetic chips, which enables simulation of fractional temperature changes during electrophoresis under real operating conditions. The accuracy of the model is within ±1°C when the deviation in electrochemical processes is taken into account. The simulation results also suggest that the temperature on the chip surface qualitatively reflects the temperature inside the microchannel with an average offset of 1–2°C.     

Modeling and Simulation of High Pressure Water Mist Systems

This paper describes work done to improve and validate the capability of fire dynamics simulator (FDS) to predict the dynamics of water mist sprays. Three single orifice and five multi-orifice spray heads are modeled with FDS based on information on the flow-rate, spray angle, operating pressure and experimentally determined particle size distribution. The capability of FDS to predict the drop size, velocity, mist flux and number concentration profiles within the spray cone is assessed. The effects of turbulence modeling on the predictions of the spray dynamics is investigated. The capability of FDS to predict the air entrainment by high-speed water sprays is validated using experiments in rectangular channels with open ends.     

A simulation study of the effect of the diverse valence-band offset and the electronic activity at the grain boundaries on the performance of polycrystalline Cu(In,Ga)Se2 solar cells

The paper presents a two-dimensional simulation study of a polycrystalline Cu(In,Ga)Se₂ (CIGS) solar cell with various shapes of grains inside the CIGS absorber layer. The grain boundaries (GBs) with a diverse valence-band offset (VBO) and the density of defect states (N_tA) are considered so as to evaluate their effects on the performance of the CIGS cell. The numerical simulations show that a CIGS cell with column-like grains can achieve a high conversion efficiency (η), while the η of a CIGS cell with diamond-like grains is low if the VBO at the GBs exceeds 0.4 eV. The VBO at which the η of the CIGS cell with diamond-like grains peaks is found at 0.20-0.27 eV. A favorable VBO mainly depends on the shape of the grains, but it also depends on the N_tA. The simulations of the CIGS cells in the substrate and superstrate configurations showed that their performances change if the VBO is varied. This result also implies that the configuration of the CIGS cell is important and the substrate configuration with larger grains in the space-charge region has a considerable advantage if the VBO ranges from 0 eV to 0.2 eV.     

Effect of fuel injection pressure on a heavy-duty diesel engine nonvolatile particle emission

The effects of the fuel injection pressure on a heavy-duty diesel engine exhaust particle emissions were studied. Nonvolatile particle size distributions and gaseous emissions were measured at steady-state engine conditions while the fuel injection pressure was changed. An increase in the injection pressure resulted in an increase in the nonvolatile nucleation mode (core) emission at medium and at high loads. At low loads, the core was not detected. Simultaneously, a decrease in soot mode number concentration and size and an increase in the soot mode distribution width were detected at all loads. Interestingly, the emission of the core was independent of the soot mode concentration at load conditions below 50%. Depending on engine load conditions, growth of the geometric mean diameter of the core mode was also detected with increasing injection pressure. The core mode emission and also the size of the mode increased with increasing NOx emission while the soot mode size and emission decreased simultaneously.     

Classification with color and texture: jointly or separately?

Current approaches to color texture analysis can be roughly divided into two categories: methods that process color and texture information separately, and those that consider color and texture a joint phenomenon. In this paper, both approaches are empirically evaluated with a large set of natural color textures. The classification performance of color indexing methods is compared to gray-scale and color texture methods, and to combined color and texture methods, in static and varying illumination conditions. Based on the results, we argue that color and texture are separate phenomena that can, or even should, be treated individually.