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Search Results: 1 - 10 of 16248 matches for " Josef-Christian Buhl "
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Synthesis of Zeolite LTN-(SOD) Self-Supporting Membranes from SiO2-Rich Industrial Waste  [PDF]
Valeriy Petrov, Josef-Christian Buhl
Journal of Materials Science and Chemical Engineering (MSCE) , 2018, DOI: 10.4236/msce.2018.63006
Abstract: Synthesis of zeolite LTN (“Linde Type N”) was investigated under insertion of a SiO2-rich filtration residue (FR) from waste water cleaning of the silane production. A new synthesis procedure was therefore developed applying a flotation mechanism with the aim to grow LTN in form of thin membrane like sheets. Preparation starts with preactivation of FR by slurrying first in alkaline solution, followed by an addition of aluminate solution and citric acid. The latter was added as suitable chelating agent for the initiation of the flotation process. In the course of these experiments, we succeeded in synthesizing zeo-lite LTN with more or less zeolite SOD as byproduct in the form of a stable compact membrane-like layer at low temperature of 60℃. The crystallization was performed under isotherm static conditions in an open reaction system without addition of organic templates as structure directing agents (OSDA’s). FR was utilized as a total substitute of sodium silicate in all experiments and an expansive pre-treatment procedure like calcinations was not needed. Furthermore, membrane formation with LTN of usual synthesis needs chemically functionalized supports. In contrast self-supporting membranous LTN layers were grown for the first time in the present study.
Investigation of the Transition Reaction of Tobermorite to Xonotlite under Influence of Additives  [PDF]
Andrea Hartmann, David Schulenberg, Josef-Christian Buhl
Advances in Chemical Engineering and Science (ACES) , 2015, DOI: 10.4236/aces.2015.52022
Abstract: The objective of the present work was to investigate the transition reaction of the calcium silicate hydrate tobermorite into xonotlite under influence of additives. Tobermorite is the main binding agent in steam hardened building materials and the appearance of xonotlite indicates the progress of hardening and an overcuring of the material. Hydrothermal experiments under addition of sucrose, calcium formate and calcium chloride dihydrate to the main components quartz and lime were done using temperatures of 220°C and a reaction time of 40.5 h. All experiments were performed with powders as well as with pressed educts. The products of all syntheses were analyzed with XRD, SEM/EDX and FTIR. The references as well as the syntheses with calcium chloride dihydrate led to the formation of 11 Å tobermorite and xonotlite. The former showed the best results and even synthesis with pressed educts and calcium chloride dihydrate revealed an accelerating effect of the additive. In contrast syntheses with sucrose had the worst reactivity and led to the formation of calcite beside the CSH-phase scawtite. The additive calcium formate was only slightly oppressing the crystallization of tobermorite and favouring the formation of xonotlite. Syntheses with pressed pellets and sucrose or calcium formate showed generally worse results.
Low Temperature Synthesis of Zeolites of the Faujasite Family (FAU-EMT) Using Industrial Mineral Waste (FR) from Silane Production  [PDF]
Valeriy Petrov, Josef-Christian Buhl
Journal of Materials Science and Chemical Engineering (MSCE) , 2017, DOI: 10.4236/msce.2016.511001
Abstract: Zeolite formation was investigated under low temperature conditions between 40°C - 25°C under insertion of a Si-rich filtration residue (FR) from waste water cleaning of the silane production. Syntheses were performed under open system conditions without stirring. The application of templates was excluded but gel formation was optimized by addition of citric acid. Beside a minimal consumption of process energy during synthesis under very low temperatures even FR was inserted without an expansive pre-treatment like calcination. Disordered intergrowths of FAU-EMT intermediates were obtained in each case, even at a temperature of only 25°C. The reaction products always occurred in two sequences, one at the bottom and another at the top of the reaction bin. A better crystallinity was detected for the latter products and the Si/Al ratio of these FAU-EMT members was close to 1.0 like in zeolite LSX. In contrast chemical analyses revealed an enrichment of Ca- and Mg- impurities from FR in the bottom products.
"Integrated Design Process" a Concept for Green Energy Engineering  [PDF]
Christian Koch, Henrik Buhl
Engineering (ENG) , 2013, DOI: 10.4236/eng.2013.53039
Abstract:

Consulting Engineers and Architects are currently experimenting with the concept of “Integrated Design Process” (IDP). This paper views Integrated Design Process as a process tool and a concept for management and organization of the green energy engineering process. Moreover such a concept is understood both as systematic knowledge and a symbolic device for enabling change. The paper briefly review international variants, and focus on two variants present in Denmark: an architect and engineering variant of IDP. The differences between the concepts include different roles for main actors, the use of information technology, the relation to lean, and forms of collaboration. The paper discusses two building projects focusing on teams of engineers and architects in the early conceptual phase. One develops a solution focused on energy saving technologies, the other on energy producing. It is argued that in this practical context, IDP is viewed as ambiguous and not well defined, and the architects and engineer work hard understanding and using the concepts even when directly involved. It is difficult to reach consensus on how to do it. The various players agree that an increased interdisciplinary interaction in the design team is necessary in order to comply with the increased complexity of green energy building design. IDP shows potential as a driver for green energy engineering and technologies, as traditional roles and responsibilities in the design process is changed, and sustainable solutions for green buildings can reach a higher standard and quality and are integrated earlier in the design process.

"...certa ternura pelo velho Zipper!": insatisfeito anseio pelo pai e fracasso do filho em Zipper e seu pai, romance de Joseph Roth
Aigner, Josef Christian;
Pandaemonium Germanicum , 2012, DOI: 10.1590/S1982-88372012000200003
Abstract: the father-son relationship has long been a cornerstone of psychoanalytic research. this article examines one such relationship, as present in joseph roth's novel zipper and his father (zipper und sein vater, 1928), in the relevant historical and psycho-social context. tracing a parallel between the fatherly figure of the austro-hungarian emperor, franz joseph, and arnold zipper's father, as well as drawing upon the narrator's (and roth's own) personal experience, the article presents an analysis of the importance of the fatherly figure and the devastating consequences of its absence.
Lattice polygons and the number 2i+7
Christian Haase,Josef Schicho
Mathematics , 2004,
Abstract: In this note we classify all triples (a,b,i) such that there is a convex lattice polygon P with area a, and b respectively i lattice points on the boundary respectively in the interior. The crucial lemma for the classification is the necessity of b \le 2 i + 7. We sketch three proofs of this fact: the original one by Scott, an elementary one, and one using algebraic geometry. As a refinement, we introduce an onion skin parameter l: how many nested polygons does P contain? and give sharper bounds.
The proof of Tchakaloff's Theorem
Christian Bayer,Josef Teichmann
Mathematics , 2005,
Abstract: We provide a simple proof of Tchakaloff's Theorem on the existence of cubature formulas of degree $m$ for Borel measures with moments up to order $m$. The result improves known results for non-compact supports, since we do not need conditions on $(m+1)$st moments.
Cubature on Wiener space in infinite dimension
Christian Bayer,Josef Teichmann
Mathematics , 2007, DOI: 10.1098/rspa.2008.0013
Abstract: We prove a stochastic Taylor expansion for SPDEs and apply this result to obtain cubature methods, i. e. high order weak approximation schemes for SPDEs, in the spirit of T. Lyons and N. Victoir. We can prove a high-order weak convergence for well-defined classes of test functions if the process starts at sufficiently regular initial values. We can also derive analogous results in the presence of L\'evy processes of finite type, here the results seem to be new even in finite dimension. Several numerical examples are added.
An inequality for adjoint rational surfaces
Christian Haase,Josef Schicho
Mathematics , 2013,
Abstract: We generalize an inequality for convex lattice polygons -- aka toric surfaces -- to general rational surfaces.
Interleukin-1 Beta (IL-1β) in the Peripheral Blood of Dogs as a Possible Marker for the Detection of Early Stages of Inflammation  [PDF]
Christian Prachar, Franz-Josef Kaup, Stephan Neumann
Open Journal of Veterinary Medicine (OJVM) , 2013, DOI: 10.4236/ojvm.2013.37049
Abstract:

Background: Cytokines are mediators of disease. Expression levels in the blood could be of clinical relevance. Objective: Aim of this study was to show if serum levels of IL-1β could be of any clinical relevance concerning dogs. IL-1β was measured in serum samples of healthy dogs to find a reference range for healthy individuals. Measurements of IL-1β should show if this substance was a possible marker for early stages of inflammation. Therefore, a possible relation between serum levels and grades of leukocytosis was analyzed. Methods: IL-1β concentrations in the blood were assessed by the use of a human enzyme linked immunosorbent assay (ELISA). 39 dogs with different inflammatory diseases were analyzed to figure out if there was a correlation between IL-1β serum levels and the number of leukocytes in peripheral blood. The control group consisted of 16 healthy dogs. Results: about half of the samples IL-1β were detected. Most of the patients showed no detectable amounts of IL-1β. The IL-1β levels measured in the serum were stable for at least nine weeks when stored at ?20?C. The patients tested positively on IL-1

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