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Clay minerals play an increasingly important role as functional fillers and reinforcing materials for clay polymer nanocomposites (CPN) in advanced applications. Among the prerequisites necessary for polymer improvement by clay minerals are homogeneous and stable Distribution of the clay mineral throughout the CPN, good compatibility of the reinforcement with the Matrix component and suitable processability. Typically, clay minerals are surface-modified with organic interface active compounds like detergents or silanes to obtain favorable properties as filler. They are incorporated into the polymer matrix using manufacturing Equipment like extruders, batch reactors or other mixing machines. In order for the surface modification to survive the stresses and strains during incorporation, the modified clay minerals must display sufficient thermal and mechanical stability to retain the compatibilizing effect. In the present study, thermogravimetry was used in combination with isoconversional kinetic analysis to determine the thermal stability of a silane-modified clay mineral based on bentonite. These findings were compared with the stability of the same clay mineral that was only surfactant-modified. It was found that silane modification leads to significantly improved thermal stability, which depends strongly on the type of silane employed.
Decorative laminates based on melamine formaldehyde (MF) resin impregnated papers are used at great extent for surface finishing of engineered wood that is used for furniture, kitchen, and working surfaces, flooring and exterior cladding. In all these applications, optically flawless appearance is a major issue. The work described here is focused on enhancing the cleanability and antifingerprint properties of smooth, matt surface-finished melamine-coated particleboards for furniture fronts, without at the same time changing or deteriorating other important surface parameters such as hardness, roughness or gloss. In order to adjust the surface polarity of a low pressure melamine film, novel interface-active macromolecular compounds were prepared and tested for their suitability as an antifingerprint additive. Two hydroxy-functional surfactants (polydimethysiloxane, PDMS-OH and perfluoroether, PF-OH) were oxidized under mild conditions to the corresponding aldehydes (PDMS-CHO and PF-CHO) using a pyridinium chlorochromate catalyst. With the most promising oxidized polymeric additive, PDMS-CHO, the contact angles against water, n-hexadecane, and squalene increased from 79.8°, 26.3° and 31.4° for the pure MF surface to 108.5°, 54.8°, and 59.3°, respectively, for the modified MF surfaces. While for the laminated MF surface based on the oxidized fluoroether the gloss values were much higher than required, for the surfaces based on oxidized polydimethylsiloxane the technological values as well as the lower gloss values were in agreement with the requirements and showed much improved surface cleanability, as was also confirmed by colorimetric measurements.
This paper studies the impact of governmental transparency on the political business cycle. The literature on electoral cycles finds evidence that cycles depend on the stage of the economy. However, we show a reliance of the cycle on transparency. We use data for G7 countries and compare it with less developed OECD countries. Our theory states that transparency reduces the political cycles due to peer pressure and by voting outs. We confirm the theory with an econometric assessment of 34 countries from 1970 to 2012. We discover smaller cycles in countries with a higher transparency, especially in G7-countries.
The powder coating of veneered particle boards by the sequence electrostatic powder application -powder curing via hot pressing is studied in order to create high gloss surfaces. To obtain an appealingaspect, veneer Sheets were glued by heat and pressure on top of particle boards and the resulting surfaceswere used as carrier substrates for powder coat finishing. Prior to the powder coating, the veneeredparticle board surfaces were pre-treated by sanding to obtain good uniformity and the boards werestored in a climate chamber at controlled temperature and humidity conditions to adjust an appropriate electrical surface resistance. Characterization of surface texture was done by 3D microscopy. The surfaceelectrical resistance was measured for the six veneers before and after their application on the particleboard surface. A transparent powder top-coat was applied electrostatically onto the veneered particleboard surface. Curing of the powder was done using a heated press at 130◦C for 8 min and a smooth, glossy coating was obtained on the veneered surfaces. By applying different amounts of powder thecoating thickness could be varied and the optimum amount of powder was determined for each veneer type.
The capability of the method of Immersion transmission ellipsometry (ITE) (Jung et al. Int Patent WO, 2004/109260) to not only determine three-dimensional refractive indices in anisotropic thin films (which was already possible in the past), but even their gradients along the z-direction (perpendicular to the film plane) is investigated in this paper. It is shown that the determination of orientation gradients in deep-sub-lm films becomes possible by applying ITE in combination with reflection ellipsometry. The technique is supplemented by atomic force microscopy for measuring the film thickness. For a photooriented thin film, no gradient was found, as expected. For a photo-oriented film, which was subsequently annealed in a nematic liquid crystalline phase, an order was found similar to the one applied in vertically aligned nematic displays, with a tilt angle varying along the z-direction. For fresh films, gradients were only detected for the refractive index perpendicular to the film plane, as expected.
Strategy to adjust people’s performance capabilities to new requirements and grantee employability in the world of work. Good examples for this are the current changes in the logistics environment. Regularly, new services and processes close to production were taken into the portfolio of logistics enterprises, so the daily Tasks are changing continuously for the skilled works.
LOPEC aims in developing and offering special-tailored training for Lean Logistics and required basic skills for skilled workers on shopfloor level. Needed know-how for today’s challenges in logistics will be transferred. Another aspect of LOPEC is the development and use of a personal excellence self-assessment that allows a Person to assess and thus improve his/her own level of maturity in employability skills. Thus, LOPEC is aiming at People ehancement as entry ticket to lifelong continuous learning by increasing the maturity level of personal logistic excellence. A common European view for “Logistics personal excellence” for skilled workers will ensure that the final product is an open product, using international, pan European validated standards. As results LOPEC will provide training modules for post-secondary education in the area of Lean Logistics, required basics skills and offers transparency of personal excellence with a personal self-assessment Software solution, regarding the personal maturity Level of hard and soft skills at any time. It can be used as an innovative tool for monitoring personal lifelong learning routes as well as within companies as a strategic tool within Human Resource Development.
This article focuses on potential economic implications of a free trade agreement (FTA) between the European Union (EU) and the Indian Federation. The economic implications are evaluated by estimating an Extended gravity model for all existing FTAs with the Indian Federation. Moreover, we control for the trade contribution of EU member countries in our econometric model during the period from 1990 until 2008. The results show a significant increase in trade, if there is a free trade agreement between India and another country. Interestingly, we find that India has the largest positive impact from FTAs with more advanced economies. Thus, we reaffirm the potential benefits of trade relationships between the EU and India.
This paper is a brief review on the book ‘Capital in the Twenty-First Century’ by the French scholar Thomas Piketty. The book has started a new debate about inequality and capital taxation in Europe. It provides interesting empirical facts and develops a theory of the functioning of capitalist economies. However, I personally think the book is less convincing than recognized in the public debate. The demonstrated theory of economic growth in the book is elusive and lacks a psychological and behavioral underpinning. In fact, I do think that the increasing inequality and economic divergence are caused by capitalism but the psychological and behavioral aspects of humans are of similar or greater significance. Therefore, Piketty’s argument does not stimulate an open and scientifically founded debate in all aspects.
Whither the german council of economic experts? The past and future of public economic advice
(2014)
The article discusses the development and impact of the German Council of Economic Experts (GCEE). Firstly, the author studies the historical origins and the institutional setup of the GCEE. In the second step, an analyse of the impact of the annual reports of the German Council is given, along with the international comparison with other advisory boards. Finally, the paper discusses the current economic challenges and the need of modernization of the GCEE in special and political advisory boards in general.
This white paper builds a new financial theory of euro area sovereign bond markets under stress. The theory explains the abnormal bond pricing and increasing spreads during the recent market turmoil. We find that the strong disconnect of bond spreads from the respective bonds’ underlying fundamental values in 2010 was triggered by an increase in asymmetric information and weak reputation of government policies. Both factors cause a normal bond market to switch into a crisis mode. Finally, those markets are prone to self-fulfilling bubbles in which the economic effects are amplified by herding behaviour arising from animal spirits. Altogether, this produces contagious effects and multiple equilibria. Thus, we argue that government bond markets in a monetary union are more fragile and vulnerable to liquidity and solvency crises. Consequently, the systemic mispricing of sovereign debt creates more macroeconomic instability and bubbles in the euro area than in a single country. In other words, financial markets are partly blind to national default risks in a currency union. Therefore, the current European institutional framework puts the wrong incentives in place and needs structural changes soon. To tackle the root causes we suggest more market incentives via consistent rules, pre-emptive austerity measures in good economic times, and a resolution scheme for heavily indebted countries. In summary, our paper enhances the bond market theory and provides new insights into the recent bond market turmoil in Europe.
This paper develops a new governance scheme for a stable and lasting European Monetary Union (EMU). I demonstrate that existing economic governance is based on flawed incentives especially due to insufficient macroeconomic coordination, failures of institutional enforcement and animal spirit in financial markets. All this caused the European sovereign debt crisis in 2010. Consequently, the EMU crisis is not a conundrum at all rather a failure of national and supranational governance. To tackle this problem, I propose a return to flexible but compulsory rules driven by market forces. The new governance principles shall promote the compliance and effective enforcement of rules.
This paper examines the relationship of asset Price determination via Google data. To capture this relation, I create a model and estimate several time series’ regressions. I use weekly data from 2004 to 2010 from 30 international banks. To my knowledge this is the first study which differentiates between Google’s search volume and Google’s search clicks. I show that asset prices are positively related to the rate of change in Google’s search volume, trading volume and the level of Google search clicks. Secondly, I demonstrate that the absolute level of Google’s search volume and Google’s search clicks
behave differently regarding the asset price dynamics. Google’s search volume, which measures long-run searches, is negatively related while Google’s search clicks have a positive relationship to asset prices. Hence, Google’s data offer new insights on both measuring attention and pricing financial assets.
Intra-operative fluoroscopy-guided assistance system for transcatheter aortic valve implantation
(2014)
A new surgical assistance system has been developed to assist the correct positioning of the AVP during transapical TAVI. The developed assistance system automatically defines the target area for implanting the AVP under live 2-D fluoroscopy guidance. Moreover, this surgical assistance system works with low levels of contrast agent for the final deployment of AVP, reducing therefore long-term negative effects, such as renal failure in the elderly and high-risk patients.
The article discusses how drama can support language learning at the university level and how drama can also support learners in acquiring professional competences. In the first part, the article will briefly outline forms of drama in language teaching. It will discuss its benefits, such as putting language in context, making learning holistic and memorable, improving learners’ social and personal competences. The second part describes aspects of drama beneficial for language learning in a professional context and gives a concrete teaching example: theatre projects with a focus on business English.
Plasma polymerization is used for the modification and control of surface properties of a highly transparent, thermoplastic elastomeric silicone copolymer, GENIOMER® 80 (G80). PEG-like diglyme plasma polymer films were deposited with ether retentions varying between 20% and 70% as measured by X-ray photoelectron spectroscopy analysis which did not affect the transparency of the substrate. Films with ether retentions of greater than 70% inhibit protein binding (bovine serum albumin and fibrinogen) and cell proliferation. A short oxygen plasma pretreatment enhances the adhesion and stability of the film as shown by protein binding and cell adhesion experiments. The transparency of the material and the stability of the coating makes this material a versatile bulk material for technical (e.g., lab-on-a-chip) and biomedical (e.g., intraocular lens) applications. The G80/plasma polymer composite is stable against vigorous washing and storage over 5 months and, therefore, offers an attractive alternative to poly(dimethylsiloxane).
There are several intra-operative use cases which require the surgeon to interact with medical devices. We used the Leap Motion Controller as input device and implemented two use-cases: 2D-Interaction (e.g. advancing EPR data) and selection of a value (e.g. room illumination brightness). The gesture detection was successful and we mapped its output to several devices and systems.
Stent graft visualization and planning tool for endovascular surgery using finite element analysis
(2014)
Purpose: A new approach to optimize stent graft selection for endovascular aortic repair is the use of finite element analysis. Once the finite element model is created and solved, a software module is needed to view the simulation results in the clinical work environment. A new tool for Interpretation of simulation results, named Medical Postprocessor, that enables comparison of different stent graft configurations and products was designed, implemented and tested. Methods Aortic endovascular stent graft ring forces and sealing states in the vessel landing zone of three different configurations were provided in a surgical planning software using the Medical Imaging Interaction Tool Kit (MITK) Software system. For data interpretation, software modules for 2D and 3D presentations were implemented. Ten surgeons evaluated the software features of the Medical Postprocessor. These surgeons performed usability tests and answered questionnaires based on their experience with the system.
Results: The Medical Postprocessor visualization system enabled vascular surgeons to determine the configuration with the highest overall fixation force in 16 ± 6 s, best proximal sealing in 56±24 s and highest proximal fixation force in 38 ± 12 s. The majority considered the multiformat data provided helpful and found the Medical Postprocessor to be an efficient decision support system for stent graft selection. The evaluation of the user interface results in an ISONORMconform user interface (113.5 points).
Conclusion: The Medical Postprocessor visualization Software tool for analyzing stent graft properties was evaluated by vascular surgeons. The results show that the software can assist the interpretation of simulation results to optimize stent graft configuration and sizing.
A vapor permeation processes for the separation of aromatic compounds from aliphatic compounds
(2014)
A number of rubbery and glassy membranes have been prepared and evaluated in vapor permeation experiments for separation of aromatic/aliphatic mixtures, using 5/95 (wt:wt) toluene/methylcyclohexane (MCH) as a model solution. Candidate membranes that met the required toluene/MCH selectivity of ≥ 10 were identified. The stability of the candidate membranes was tested by cycling the experiment between higher toluene concentrations and the original 5 wt% level. The best membrane produced has a toluene permeance of 280 gpu and a toluene/MCH selectivity of 13 when tested with a vapor feed of the model mixture at its boiling point and at atmospheric pressure. When a series of related membrane materials are compared, there is a sharp trade-off between membrane permeance and membrane selectivity. A process design study based on the experimental results was conducted. The best preliminary membrane design uses 45% of the energy of a conventional distillation process.
The analysis of exhaled metabolites has become a promising field of research in recent decades. Several volatile organic compounds reflecting metabolic disturbance and nutrition status have even been reported. These are particularly important for long-term measurements, as needed in medical research for detection of disease progression and therapeutic efficacy. In this context, it has become urgent to investigate the effect of fasting and glucose treatment for breath analysis. In the present study, we used amodel of ventilated rats that fasted for 12 h prior to the experiment. Ten rats per group were randomly assigned for continuous intravenous infusion without glucose or an infusion including 25 mg glucose per 100 g per hour during an observation period of 12 h. Exhaled gas was analysed using multicapillary column ion-mobility spectrometry. Analytes were identified by the BS-MCC/IMS database (version 1209; B & S Analytik, Dortmund, Germany). Glucose infusion led to a significant increase in blood glucose levels (p<0.05 at 4 h and thereafter) and cardiac output (p<0.05 at 4 h and thereafter). During the observation period, 39 peaks were found collectively. There were significant differences between groups in the concentration of ten volatile organic compounds: p<0.001 at 4 h and thereafter for isoprene, cyclohexanone, acetone, p-cymol, 2-hexanone, phenylacetylene, and one unknown compound, and p<0.001 at 8 h and thereafter for 1-pentanol, 1-propanol, and 2-heptanol. Our results indicate that for long-term measurement, fasting and the withholding of glucose could contribute to changes of volatile metabolites in exhaled air.
In breath analysis, ambient air contaminations are ubiquitous and difficult to eliminate. This study was designed to investigate the reduction of ambient air background by a lung wash-out with synthetic air. The reduction of the initial ambient air volatile organic compound (VOC) intensity was investigated in the breath of 20 volunteers inhaling synthetic air via a sealed full face mask in comparison to inhaling ambient air. Over a period of 30 minutes, breath analysis was conducted using ion mobility spectrometry coupled to a multi-capillary column. A total of 68 VOCs were identified for inhaling ambient air or inhaling synthetic air. By treatment with synthetic air, 39 VOCs decreased in intensity, whereas 29 increased in comparison to inhaling ambient air. In total, seven VOCs were significantly reduced (P-value < 0.05). A complete wash-out of VOCs in this setting was not observed, whereby a statistically significant reduction up to 65% as for terpinolene was achieved. Our setting successfully demonstrated a reduction of ambient air contaminations from the airways by a lung wash-out with synthetic air.