Thermochemical production of hydrogen by a vanadium/chlorine cycle. Part 1: An energy and exergy analysis of the process

A vanadium/chlorine water-splitting process for the thermochemical production of hydrogen was investigated both energetically (Part 1) and experimentally (Part 2). A detailed mass and energy balance is given and discussed, starting out from the process flowsheeting developed. Balancing and optimization of the total process followed, based on experimental results from the individual reactions. The total process includes a steam power plant for producing the required electrical power. This is integrated into the thermochemical process. Results of the mass and energy balances are shown and discussed in detail. The overall efficiency of the plant is 42.5%.     

Using tissue samples for proteomic studies—Critical considerations

From my experience of 22 years working in a pathology research laboratory and overseeing dozens of collaborations with research groups from basic sciences and industry, I have the impression that researchers are rarely aware of the special issues related to acquisition and processing of frozen or formalin-fixed tissue samples for proteomic analysis. While challenges are expected for formalin-fixed tissues because of the cross-linking activities of formaldehyde, researchers believe when using frozen tissue samples they are safe and always have excellent material to analyze—but this is not always the case. It is alarming that many researchers do not question the quality of the tissue samples they are analyzing and focus only on their analytical technique. Standardization of the entire workflow from test ordering to the report of the proteomic assay, with special emphasis on the preanalytical phase, is crucial for successful integration of proteomic studies in the clinic as protein profiles may change due to sample processing before the proteomic analysis is performed. The aim of this review is to discuss the progress of proteomic studies with human tissues and to highlight the challenges that must be understood and addressed for successful translation of proteomic methods to clinical practice.     

Guided protein extraction from formalin-fixed tissues for quantitative multiplex analysis avoids detrimental effects of histological stains

Formalin fixed and paraffin embedded (FFPE) tissues are the basis for histopathological diagnosis of many diseases around the world. For translational research and routine diagnostics, protein analysis from FFPE tissues is very important. We evaluated the potential influence of six histological stains, including hematoxylin (Mayer and Gill), fast red, light green, methyl blue and toluidine blue, for yield, electrophoretic mobility in 1-D gels, and immunoreactivity of proteins isolated from formalin-fixed breast cancer tissues. Proteins extracted from stained FFPE tissues using a recently established technique were compared with proteins obtained from the same tissues but without prior histological staining. Western blot and quantitative protein lysate microarray analysis demonstrated that histological staining can result in decreased protein yield but may not have much influence on immunoreactivity and electrophoretic mobility. Interestingly, not all staining protocols tested are compatible with subsequent protein analysis. The commonly used hematoxylin staining was found to be suitable for multiplexed quantitative protein measurement technologies although protein extraction was less efficient. For best results we suggest a guided protein extraction method, in which an adjacent hematoxylin/eosin-stained tissue section is used to control dissection of an unstained specimen for subsequent protein extraction and quantification for research and diagnosis.     

Synthesis of novolac on the basis of bisphenol A as curing agent for epoxy resins

Bisphenol A novolacs were synthesized in a melting process using paraformaldehyde, and in a solution process using a formalin solution and oxalic acid catalyst. ¹H-NMR investigations show a higher content of methylene bridges in the novolacs synthesized in a melting process. These novolacs were analysed by HPLC, GPC, DSC and FT-IR spectroscopy. The molecular masses were determined by vapour pressure osmometry. The results were shown to be related with the molar ratio of the components. The bisphenol A novolacs were used as curing agents for epoxy resins. There exists a dependence of the gel times on the content of methylene bridges; this dependence is influenced by temperature. The activation energy for gel formation is nearly the same in all curing reactions investigated. The networks synthesized were investigated by thermomechanical analysis.     

Eine neue Methode zur Bestimmung des Molekulargewichts von Polymeren durch Ultrazentrifugation

The Lamm differential equation (DG) for the ultracentrifuge was solved for the case δc/δt ≠ 0 experimentally. The concentration gradient in the ultracentrifuge cell was determined by measuring the refractive index increment as well as the UV-absorption. Thus by simultaneously determining sedimentation and diffusion coefficient a new method for absolute molecular weight measurement was obtained.     

Pressure jump method with detection of optical rotation and circular dichroism

A pressure jump technique for fast kinetics using optical rotation and circular dichroism detection is presented and a suitable cell design for both detection methods is discussed. The detectability of changes in optical rotation far away from the Cotton region is considered, and measurements made on a pressure-dependent folding reaction of the protein serum albumin are given as an application.     

Operation data of a directly fired absorption heating unit with periodically operating absorber

This contribution presents the layout, construction, and experimental investigation of operation behaviour of a directly fired absorption heating unit with periodically operating absorber. The working system is CH₃OH-LiBr/LiOH. The unit is designed to generate a maximum heat load of 10 kW. The field of application is mainly in domestic heatIng. A special feature of the absorption heating unit is the provision of the major part of required process heat in the heat pump mode of operation with high efficiency. At extremely low ambient air temperatures, heat is supplied in the direct mode. A numerical simulation routine is also described. The simulation program describes both steady-state and dynamic processes in the unit. With models for each component, the performance of individual components can be studied and optimized. The results presented here consist of the first experimentally obtained efficiencies in direct heating mode, results of numerical simulation of the component generator, and a comparison of measured and predicted characteristic system temperatures.     

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