The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform
D Bendler - One of the best experts on this subject based on the ideXlab platform.
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esca investigations on schleenhain lignite lithotypes and the hydrogenation residues
Fuel, 1992Co-Authors: R. Fiedler, D BendlerAbstract:Abstract Electron spectroscopy for chemical Analysis (ESCA) was carried out on Schleenhain lignite lithotypes (yellow, brown and black) and the hydroliquefaction residues. The hydrogenation was carried out over the temperature range of 330–450 °C. ESCA is a Surface Analysis Method, but owing to special sample pretreatment the element concentrations and the binding forms of oxygen and sulphur were estimated in the same way as for a bulk Method. The concentration changes of oxygen, sulphur and nitrogen in the organic matter are characteristic of hydrogenation conditions and sample properties. The investigation of oxygen and, especially, sulphur binding forms allows further insight into lithotype reactivity. For characterization of organic sulphur groups oxidation with H 2 O 2 in an acidic medium was carried out. In this manner, bridging and non-bridging and reactive and non-reactive sulphur forms were distinguished. Some sulphur atoms are resistant to oxidation and hydrogenation; these sulphur atoms were enriched in the residues by the hydrogenation process. The enrichments are due to the original coal's properties. A phosphorus-containing catalyst retarded the formation of active iron sulphides in the hydrogenation reaction.
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esca investigations on schleenhain lignite lithotypes and the hydrogenation residues
Fuel, 1992Co-Authors: R. Fiedler, D BendlerAbstract:Abstract Electron spectroscopy for chemical Analysis (ESCA) was carried out on Schleenhain lignite lithotypes (yellow, brown and black) and the hydroliquefaction residues. The hydrogenation was carried out over the temperature range of 330–450 °C. ESCA is a Surface Analysis Method, but owing to special sample pretreatment the element concentrations and the binding forms of oxygen and sulphur were estimated in the same way as for a bulk Method. The concentration changes of oxygen, sulphur and nitrogen in the organic matter are characteristic of hydrogenation conditions and sample properties. The investigation of oxygen and, especially, sulphur binding forms allows further insight into lithotype reactivity. For characterization of organic sulphur groups oxidation with H 2 O 2 in an acidic medium was carried out. In this manner, bridging and non-bridging and reactive and non-reactive sulphur forms were distinguished. Some sulphur atoms are resistant to oxidation and hydrogenation; these sulphur atoms were enriched in the residues by the hydrogenation process. The enrichments are due to the original coal's properties. A phosphorus-containing catalyst retarded the formation of active iron sulphides in the hydrogenation reaction.
R. Fiedler - One of the best experts on this subject based on the ideXlab platform.
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esca investigations on schleenhain lignite lithotypes and the hydrogenation residues
Fuel, 1992Co-Authors: R. Fiedler, D BendlerAbstract:Abstract Electron spectroscopy for chemical Analysis (ESCA) was carried out on Schleenhain lignite lithotypes (yellow, brown and black) and the hydroliquefaction residues. The hydrogenation was carried out over the temperature range of 330–450 °C. ESCA is a Surface Analysis Method, but owing to special sample pretreatment the element concentrations and the binding forms of oxygen and sulphur were estimated in the same way as for a bulk Method. The concentration changes of oxygen, sulphur and nitrogen in the organic matter are characteristic of hydrogenation conditions and sample properties. The investigation of oxygen and, especially, sulphur binding forms allows further insight into lithotype reactivity. For characterization of organic sulphur groups oxidation with H 2 O 2 in an acidic medium was carried out. In this manner, bridging and non-bridging and reactive and non-reactive sulphur forms were distinguished. Some sulphur atoms are resistant to oxidation and hydrogenation; these sulphur atoms were enriched in the residues by the hydrogenation process. The enrichments are due to the original coal's properties. A phosphorus-containing catalyst retarded the formation of active iron sulphides in the hydrogenation reaction.
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esca investigations on schleenhain lignite lithotypes and the hydrogenation residues
Fuel, 1992Co-Authors: R. Fiedler, D BendlerAbstract:Abstract Electron spectroscopy for chemical Analysis (ESCA) was carried out on Schleenhain lignite lithotypes (yellow, brown and black) and the hydroliquefaction residues. The hydrogenation was carried out over the temperature range of 330–450 °C. ESCA is a Surface Analysis Method, but owing to special sample pretreatment the element concentrations and the binding forms of oxygen and sulphur were estimated in the same way as for a bulk Method. The concentration changes of oxygen, sulphur and nitrogen in the organic matter are characteristic of hydrogenation conditions and sample properties. The investigation of oxygen and, especially, sulphur binding forms allows further insight into lithotype reactivity. For characterization of organic sulphur groups oxidation with H 2 O 2 in an acidic medium was carried out. In this manner, bridging and non-bridging and reactive and non-reactive sulphur forms were distinguished. Some sulphur atoms are resistant to oxidation and hydrogenation; these sulphur atoms were enriched in the residues by the hydrogenation process. The enrichments are due to the original coal's properties. A phosphorus-containing catalyst retarded the formation of active iron sulphides in the hydrogenation reaction.
Liu Min - One of the best experts on this subject based on the ideXlab platform.
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Multipath mitigation based on trend Surface Analysis applied to dual-antenna receiver with common clock
GPS Solutions, 2019Co-Authors: Zhiren Wang, Wen Chen, Danan Dong, Minghua Wang, Miaomiao Cai, Zhengqi Zheng, Liu MinAbstract:Multipath mitigation Methods based on the intrinsic spatiotemporal repeatability of multipath effect are commonly applied in high-precision Global Navigation Satellite System positioning. Among which multipath hemispherical map (MHM) has the advantages of simplicity of calculation and real-time multipath reduction of static environment or some dynamic environment. However, utilizing the average of residuals as the calibration values will inevitably lead to insufficient or excessive modification of multipath in the lattice. We proposed an advanced multipath elimination Method named trend Surface Analysis-based multipath hemispherical map (T-MHM), which extends the primary MHM by combining the trend Surface Analysis Method to investigate the multipath spatial distribution and trend in each lattice. A short baseline experiment was carried out using a dual-antenna receiver with common clock in campus of East China Normal University. Single-difference carrier residuals were used for relative multipath modeling. The multipath elimination results indicate that, compared with the original approach, the T-MHM improves the dispersion and accuracy of the baseline solution and increases the phase observation residuals reduction rate. It also enhances the modeling of multipath information in both low- and high-frequency bands. Meanwhile, T-MHM is less sensitive to lattice size. In practical applications, larger lattice size can be adopted to improve the computational efficiency and spatial coverage with little loss of accuracy.
José A. Revilla - One of the best experts on this subject based on the ideXlab platform.
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Surface Analysis of free Surface and velocity to changes in river flow and tidal amplitude on a shallow mesotidal estuary: An application in Suances Estuary (Nothern Spain)
Journal of Hydrology, 2011Co-Authors: Javier F. Bárcena, Andrés García, Javier García, César Álvarez, José A. RevillaAbstract:Summary Details are given of the Surface Analysis Method implementation to characterize the free Surface and velocity influences of a shallow mesotidal estuary to changes in freshwater discharges, with particular application to the Suances Estuary (SE), located in north of Spain. The Surface Analysis Method is based on the use of numerical models in order to assess water levels and current velocities in several model scenarios which represent the environmental forcing variability in the estuary. Thus, a two-dimensional depth-integrated model was used to evaluate water levels and current velocities in the innermost area of the SE, applying a mesh nesting strategy to achieve high resolution results in order to evaluate the pollutant transport in further studies. The hydrodynamic model was calibrated and validated against field data, collected during spring and neap tidal cycles, for water levels and current velocities. This tool allowed us to study a set of 45 model scenarios under fixed river flow and tidal amplitude conditions. These results were then fitted trough quadratic interpolation functions to create plots of response Surfaces for the mentioned variables. From these Surfaces, water levels and velocity distributions can be calculated for long-term periods at any estuarine location saving a remarkable quantity of computational cost and time. To validate the Surface Analysis Method, the obtained results were tested against the outputs provided by the hydrodynamic modelling of the estuary for a 6-month period. The comparison showed a fairly good agreement with less computational cost than a typical numerical modelling, obtaining a computational demand decrease of 55%. Although, it is relevant to mention that the Surface Analysis Method performs better in estimating velocities than water levels, we evaluated the river flow and astronomic tide influence on estuarine water levels and current velocities for a long-term period of 10 years.
Shailesh A. Shah - One of the best experts on this subject based on the ideXlab platform.
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Quality Risk Management Based: Analytical Quality by Design Approach to Eco-Friendly and Versatile Chromatography Method for Simultaneous Estimation of Multiple Fixed-Dose-Combination Products of Anti-Diabetic Drugs
Journal of Pharmaceutical Innovation, 2020Co-Authors: Pintu B. Prajapati, Khushbu Radadiya, Shailesh A. ShahAbstract:Purpose The chromatography Methods such as HPLC, HPTLC etc. were developed for simultaneous estimation of multiple fixed-dose combination products of metformin hydrochloride which need single chromatography condition to save solvent consumption. The Method was developed by the implementation of analytical quality by design approach based on principles of quality risk management (QRM) and design of experiments (DoE) as per regulatory requirements. Methods QRM was applied for the Analysis of twenty potential Method risk parameters using the Ishikawa diagram and quality risk assessment according to ICH Q9 guideline. DoE was applied by Taguchi OA screening design and Box-Behnken response Surface Analysis Method. Method operable design range was navigated for optimisation of critical Method risk parameters as per the analytical target profile for development of the Method. The developed Method was applied for the Analysis of three different fixed-dose combination products of metformin hydrochloride. Results By the QRM process, seven Method risk parameters were found critical for the development of the Method. After the Taguchi screening design, the main effect of mobile phase composition, %w/v of ammonium acetate and saturation time was found to be significant. The results of the Box-Behnken design showed a quadratic relationship between CMPs and CMAs. The developed Method was found to be specific, accurate and precise. The results of the assay were found in good agreement with the labelled claim. Conclusion The developed Method can analyse three different fixed-dose combination products of metformin hydrochloride which required three different chromatography Methods. Hence, the Method is versatile and eco-friendly.