Untersuchungen zur Zeolithsynthese unter Einsatz von Filterrückständen der Silanproduktion

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Synthesis of Zeolite LTN-(SOD) Self-Supporting Membranes from SiO2-Rich Industrial Waste

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

Low Temperature Synthesis of Zeolites of the Faujasite Family (FAU-EMT) Using Industrial Mineral Waste (FR) from Silane Production

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

Models, methods and information technologies of protection of corporate systems of transport based on intellectual identification of threats

In article results of researches on development of methods and models of intellectual recognition of threats to information systems of transport. The article to contain results of the researches, allowing to raise level of protection of the automated and intellectual information systems of the transportation enterprises (AISTE) in the conditions of an intensification of transportations.  The article to contain mathematical models and results of an estimation information systems having Internet connection through various communication channels. The article also considers the issues of research and protection of the AISTE under the condition of several conflict data request threads

Efficient generation of few-cycle pulses beyond 10 μm from an optical parametric amplifier pumped by a 1-µm laser system

Nonlinear vibrational spectroscopy profits from broadband sources emitting in the molecular fingerprint region. Yet, broadband lasers operating at wavelengths above 7 μm have been lacking, while traditional cascaded parametric frequency down-conversion schemes suffer from exceedingly low conversion efficiencies. Here we present efficient, direct frequency down-conversion of femtosecond 100-kHz, 1.03-μm pulses to the mid-infrared from 7.5 to 13.3 μm in a supercontinuum-seeded, tunable, single-stage optical parametric amplifier based on the wide-bandgap material Cd0.65Hg0.35Ga2S4. The amplifier delivers near transform-limited, few-cycle pulses with an average power > 30 mW at center wavelengths between 8.8 and 10.6 μm, at conversion efficiencies far surpassing that of optical parametric amplification followed by difference-frequency generation or intrapulse difference-frequency generation. The pulse duration at 10.6 μm is 101 fs corresponding to 2.9 optical cycles with a spectral coverage of 760–1160 cm−1. CdxHg1−xGa2S4 is an attractive alternative to LiGaS2 and BaGa4S7 in small-scale, Yb-laser-pumped, few-cycle mid-infrared optical parametric amplifiers and offers a much higher nonlinear figure of merit compared to those materials. Leveraging the inherent spatial variation of composition in CdxHg1−xGa2S4, an approach is proposed to give access to a significant fraction of the molecular fingerprint region using a single crystal at a fixed phase matching angle.Peer Reviewe

High-brightness seven-octave carrier envelope phase-stable light source

High-brightness sources of coherent and few-cycle-duration light waveforms with spectral coverage from the UV to the THz would offer unprecedented versatility and opportunities for a spectacular range of applications from bio-chemical sensing, to time-resolved and nonlinear spectroscopy, to attosecond light-wave electronics. Combinations of various sources with frequency conversion and supercontinuum generation can provide relatively large spectral coverage, but many applications require much broader spectral range and low-jitter synchronization for time-domain measurements. Here, we present a carrier-envelope-phase stable light source, seeded by a mid-IR frequency comb, with simultaneous spectral coverage across 7 optical octaves, from the UV (340 nm) into the THz (40,000 nm). Combining soliton self-compression and dispersive wave generation in an anti-resonant-reflection photonic crystal fibre with intra-pulse difference frequency generation in BaGa2GeSe6, the spectral brightness is 2-5 orders of magnitude above synchrotron sources. This enables high-dynamic-range spectroscopies and provides enticing prospects for attosecond physics and material sciences.Comment: 4 figure

International Geomagnetic Reference Field: the 12th generation

The 12th generation of the International Geomagnetic Reference Field (IGRF) was adopted in December 2014 by the Working Group V-MOD appointed by the International Association of Geomagnetism and Aeronomy (IAGA). It updates the previous IGRF generation with a definitive main field model for epoch 2010.0, a main field model for epoch 2015.0, and a linear annual predictive secular variation model for 2015.0-2020.0. Here, we present the equations defining the IGRF model, provide the spherical harmonic coefficients, and provide maps of the magnetic declination, inclination, and total intensity for epoch 2015.0 and their predicted rates of change for 2015.0-2020.0. We also update the magnetic pole positions and discuss briefly the latest changes and possible future trends of the Earth’s magnetic fiel

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe