Preparation and Thermoplastic Processing of Modified Plant Proteins

Native plant proteins such as gluten, zein, soy and pea protein were chemically modified by acylation reactions using palmitic acid chloride and alkenyl‐substituted succinic anhydrides, respectively. The goal of this work was the development of novel, biodegradable protein materials, which are processable by thermoplastic shaping in extruders. Structures and properties of modified plant proteins were characterized by elementary analysis, IR, DSC, TGA, water retention analysis, and tensile tests. The biodegradability of the acylated protein derivatives has been demonstrated. It can be concluded that the chosen plant proteins are suitable for acylation reactions leading to fusible thermoplastic materials with improved water‐resistance. However, resultant extruded articles possess mostly high brittleness combined with low tensile strength. An improved processability and mechanical performance of the acylated products can be achieved by addition of only 10% glycerol.

     

工业配电网经中性点低电阻接地改进后的运行状况

1初始状况Volkswagenwerk AG经营管理着一个6 kV系统向它的Emden工厂提供电力。该电力系统按两个在电气上各自独立的子系统运行,每个子系统以两台110/6 kV变压器供电。从变电所和6 kV开关室经一路短电缆馈线供两台6/0.4 kV变压器。在备用情况时,这路短电缆馈线可从对端经备用电缆供电。6 kV开关室由两条电缆供电。从变电所和开关室的馈出线路上都有过电流时间继电器保护。馈入线路的电流互感器额定值为2 500/5 A,供电电缆上为1 000/5 A,其余馈出线路上为300/5 A或400/5 A。工厂装用的过电流时间继电器是老式的电气机械和模拟电子式的…     

Heat and mass transfer analysis of a wavy fin-and-tube heat exchanger under fully and partially wet surface conditions

In this study a mathematical model of heat and mass transfer performance of a wavy fin-and-tube heat exchanger under wet surface condition is presented. The heat exchanger is a counterflow heat exchanger in which humid air and liquid are flowing in opposite direction. A water film that causes evaporative cooling of the humid air is circulated on the humid air side. The heat and mass transfer equations are first derived for fully wet heat exchanger and then by defining a wettability parameter, these equations are obtained for partially wet heat exchanger. In modeling, values of Lewis number and wettability parameter are not necessarily specified as unity. The temperature distributions of humid air, liquid and water film, and relative humidity distribution of humid air are obtained numerically. The theoretical results are found to be in good agreement with the available experimental measurements.     

And Yet It Moves: Oxidation of the Nuclear Autoantigen La/SS-B Is the Driving Force for Nucleo-Cytoplasmic Shuttling

Decades ago, we and many other groups showed a nucleo-cytoplasmic translocation of La protein in cultured cells. This shuttling of La protein was seen after UV irradiation, virus infections, hydrogen peroxide exposure and the Fenton reaction based on iron or copper ions. All of these conditions are somehow related to oxidative stress. Unfortunately, these harsh conditions could also cause an artificial release of La protein. Even until today, the shuttling and the cytoplasmic function of La/SS-B is controversially discussed. Moreover, the driving mechanism for the shuttling of La protein remains unclear. Recently, we showed that La protein undergoes redox-dependent conformational changes. Moreover, we developed anti-La monoclonal antibodies (anti-La mAbs), which are specific for either the reduced form of La protein or the oxidized form. Using these tools, here we show that redox-dependent conformational changes are the driving force for the shuttling of La protein. Moreover, we show that translocation of La protein to the cytoplasm can be triggered in a ligand/receptor-dependent manner under physiological conditions. We show that ligands of toll-like receptors lead to a redox-dependent shuttling of La protein. The shuttling of La protein depends on the redox status of the respective cell type. Endothelial cells are usually resistant to the shuttling of La protein, while dendritic cells are highly sensitive. However, the deprivation of intracellular reducing agents in endothelial cells makes endothelial cells sensitive to a redox-dependent shuttling of La protein.     

Das digitale geologische Strukturmodell Bitterfeld als neuer Baustein in der Sanierungsforschung

Identification, assessment and remediation of a large-scale groundwater contamination requires a profound knowledge of the geological structure to predict the fate of contaminants in the subsurface. Within the SAFIRA-project, a model sector of the Bitterfeld/Wolfen area was chosen to transfer the structural geological data of the Tertiary and Quarternary aquifer units into a digital geological model. Using 125 selected drillholes as a base of 28 networked cross-sections, small-scale lithological and structural heterogeneities, in particular of the Quarternary layers, could be assigned to 31 litho-stratigraphic sedimentation units and depicted using a 10 × 10 m GIS grid. An assignment of hydraulic parameters to individual sedimentary bodies allows a combination with flow and transport models. The structural model was generated by combining gridding sections and additional point and lateral information of sediment distribution and allows -beyond visualisation purposes- volumetric calculations of distinct sedimentary units, which are relevant for an assessment of retardation processes in the remaining lignite seam. The present structural model is the base for a “Spatial Model Bitterfeld” and anables further investigations on the environmental impact of different scenarios.     

Integration von Sach- und Dienstleistungen – Ausgewählte Internetquellen zur hybriden Wertschöpfung

The article presents results of an internet research on product-service systems. Web sites showing interesting practical examples and studies available online are presented to point out the practical relevance of innovative combinations of products and services. The multiplicity of research projects found on the internet shows that this phenomenon is also discussed intensively in research. These projects have been categorized by analyzing their web sites. Furthermore, the results of the internet research highlight a high diversity of terms for describing the concept of product-service systems. As a consequence, orientation in this subject area is hindered.     

Potentials of precision machining processes for the manufacture of micro forming molds

Molds for micro forming processes require specific functional surfaces to provide optimized tribological condition for forming processes. Such topographies with microscopic dimensions can for instance be generated by lithographical methods. However, a main disadvantage of these processes is their low flexibility, e.g. changing the structures to be generated causes extensive adaptations in the manufacturing process. Therefore, mechanical precision machining processes like micro milling, micro grinding and micro polishing are appropriate processes for the manufacture of micro molds of manifold shapes and with well suited micro topographies.