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51.
In the present work, the microstructural evolution and hardness of HSLA X70 joined by friction stir welding were investigated. The FSW was applied to HSLA X70 with and without the addition of titanium dioxide (TiO2) powders. To evaluate the microstructural features and hardness of different weld zones, optical microscopy and Vickers microhardness measurements were applied. The results show that the distribution of TiO2 powders is strongly dependent on the applied friction stir processing, which in turn changed significantly the microstructure and hardness profile. In this regard, the optimum stirring action resulted in a homogeneous and fine dispersion of particles leading to the domination of an acicular ferrite phase with a hardness of 370 HV. On the other hand, the lower stirring action resulted in coarse particles as well as the development of the polygonal ferrite structure with a hardness of ~185 HV. 相似文献
52.
Rudolf Sowada 《Advanced Synthesis \u0026amp; Catalysis》1981,323(2):269-278
On the Lipophilic Nature of Oxyalkyl Groups in Alkyl Ether Sulphates Effective carbon numbers and methylene group equivalent values for tetradecane sulphonates containing oxyalkyl groups as substituents as well as and for alkyl ether sulphates containing oxyalkyl groups in the chain have been calculated. These oxyethyl groups show lipophilic character, at least up to an oxethylation degree of 10. Via ME values effective carbon numbers, critical concentrations for micelle formation and HLB-values for alkyl ether sulphates can be calculated. HLB group numbers depending on oxalkylation degree are tabulated; the known value of + 0,33 for OCH2CH2 is valid only for nonionic surfactants. 相似文献
53.
The arc furnace technology is an ideally suited process for the treatment of hazardous and problematic waste. The operation conditions of the arc furnace can be adapted for optimal transformation of the waste material input into raw materials and usable products. The process can significantly reduce the impact of contaminated wastes and industrial residues, and enable material conversion and separation. Thus, the products of the process have various applications.
The capability of the process is illustrated with three examples, the treatment of bottom ash and filter ash from waste incineration plants, of stainless steel slags and of chromium containing residues from the refractory industry. 相似文献
54.
Composition of a protein-like fluorophore of dissolved organic matter in coastal wetland and estuarine ecosystems 总被引:9,自引:0,他引:9
This study demonstrates the compositional heterogeneity of a protein-like fluorescence emission signal (T-peak; excitation/emission maximum at 280/325 nm) of dissolved organic matter (DOM) samples collected from subtropical river and estuarine environments. Natural water samples were collected from the Florida Coastal Everglades ecosystem. The samples were ultrafiltered and excitation-emission fluorescence matrices were obtained. The T-peak intensity correlated positively with N concentration of the ultrafiltered DOM solution (UDON), although, the low correlation coefficient (r(2)=0.140, p<0.05) suggested the coexistence of proteins with other classes of compounds in the T-peak. As such, the T-peak was unbundled on size exclusion chromatography. The elution curves showed that the T-peak was composed of two compounds with distinct molecular weights (MW) with nominal MWs of about >5 x 10(4) (T(1)) and approximately 7.6 x 10(3) (T(2)) and with varying relative abundance among samples. The T(1)-peak intensity correlated strongly with [UDON] (r(2)=0.516, p<0.001), while T(2)-peak did not, which suggested that the T-peak is composed of a mixture of compounds with different chemical structures and ecological roles, namely proteinaceous materials and presumably phenolic moieties in humic-like substances. Natural source of the latter may include polyphenols leached from senescent plant materials, which are important precursors of humic substances. This idea is supported by the fact that polyphenols, such as gallic acid, an important constituent of hydrolysable tannins, and condensed tannins extracted from red mangrove (Rhizophora mangle) leaves exhibited the fluorescence peak in the close vicinity of the T-peak (260/346 and 275/313 nm, respectively). Based on this study the application of the T-peak as a proxy for [DON] in natural waters may have limitations in coastal zones with significant terrestrial DOM input. 相似文献
55.
Piotr Długosz Angelika Rączka Adrian Kopeć Rudolf Krzyżak Paweł Darłak Marek Hebda 《Journal of Materials Engineering and Performance》2016,25(6):2261-2266
This paper presents novel opportunities for management of fly ash by synthesizing the material into cordierite ceramics and using it as a reinforcing phase for light metal alloys. Metal matrix composites (based on magnesium alloy and aluminum alloy) were produced by squeeze casting. The magnesium matrix composites with a suitably selected reinforcing phase content (2 wt.%) exhibited much better strength properties than the unmodified alloy (AM60). It was also demonstrated that the wettability (or the lack thereof) in the metal-ceramic system is critical to successful production of the composites based on the AK7 alloy with cordierite. Light alloy matrix composites reinforced with cordierite ceramics particles are innovative materials that combine high strength with low weight, which may be a key factor of merit for numerous applications of the composite in various branches of industries. 相似文献
56.
57.
André Dias Lukas Gorzelniak Rudolf A. Jörres Rainald Fischer Gunnar Hartvigsen Alexander Horsch 《Pervasive and Mobile Computing》2012,8(6):837-844
Physical Activity (PA) plays an important role in the health and quality of life of cystic fibrosis (CF) patients, but little is known about their PA in daily living. With the use of accelerometers it is now possible to monitor activity profiles in detail. The goals of this study are to assess feasibility and acceptance of a longer-term use of accelerometers in daily living in CF patients, study the possibility of detecting changes in PA in relation to the patients’ clinical state and compare the findings between a CF and an age-matched healthy control group. We asked 15 CF patients to wear two accelerometers for 21 days and fill in a diary. Ten of them (age 21 to 40, mean 29.5 years) participated and delivered data that could be evaluated. We also recruited 10 age-matched control subjects. Data was processed for calculating usage time and features extracted to construct models of activity. The younger patients, particularly females, were concerned with fashion and style and considered wearing the sensors a challenge. Overall, the compliance of patients with CF seemed to be lower than reported for elder subjects in the literature. Time-series analysis of the data indicated characteristic patterns of PA over time, provided that data pre-processing and noise-filtering had been optimized. Further studies have to assess whether the continuous recording of PA yields additional clinical information in CF and in particular, whether it is possible to detect or even predict exacerbations in patients with CF or other diseases. 相似文献
58.
Christian Überall Christopher Köhnen Veselin Rakocevic Rudolf Jäger Erich Hoy Muttukrishnan Rajarajan 《Multimedia Tools and Applications》2013,62(3):785-820
This paper presents novel algorithms which are able to generate recommendations within a heterogeneous service environment. In this work explicitly set preferences as well as implicitly logged viewing behavior are employed to generate recommendations for Digital Video Broadcast (DVB) content. This paper also discusses the similarity between the DVB genres and YouTube categories. In addition it presents results to show the comparison between well known collaborative filtering methods. The outcome of this comparison study is used to identify the most suitable filtering method to use in the proposed environment. Finally the paper presents a novel Personal Program Guide (PPG), which is used as a tool to visualize the generated recommendations within a heterogeneous service environment. This PPG is also capable of showing the linear DVB content and the non-linear YouTube videos in a single view. 相似文献
59.
Maike Gleichenhagen Benno F. Zimmermann Birgit Herzig Ingar Janzik Siegfried Jahnke Markus Boner Peter Stehle Rudolf Galensa 《Food chemistry》2013
The intrinsic isotopic labelling of plants with 13CO2 is an effective method to generate highly labelled compounds using photosynthesis and avoiding labour-intensive complex organic syntheses. In this study, the intrinsic isotopic labelling of polyphenols in parsley, spinach and peppermint is shown for the first time. The plants were grown in an atmosphere where 12CO2 was replaced by 13CO2, in order to generate highly labelled compounds. The total content of 13C as well as the individual polyphenols were analysed by Isotopic Ratio-MS and HPLC–Iontrap-MSn. 相似文献
60.
Thomas Beer Tobias Meisen Rudolf Reinhard Sergey Konovalov Daniel Schilberg Sabina Jeschke Torsten Kuhlen Christian Bischof 《Production Engineering》2011,5(4):383-391
Computational simulations are used for the optimization of production processes in order to significantly reduce the need
for costly experimental optimization approaches. Yet individual simulations can rarely describe more than a single production
step. A set of simulations has to be coupled to each other to form a contiguous representation of a process chain. Eventually,
simulated results have to be analyzed by domain experts to gather insight from the preformed computations. In this paper,
we propose an IT infrastructure and software tools that aim at a rather non-intrusive way of coupling resources and domain
expert’s knowledge to enable the collaborative setup, execution and analysis of distributed simulation chains. We illustrate
the approach in the domain of materials processing. Beyond means originating from the domain of GRID computing for resource
management, a data integration component assures semantic data integrity between the simulation steps and stores simulation
data in an application independent way. Thus, we can transform this data into native formats for each simulation tool, and
finally into a format that allows for contiguous visualizations and an intuitive, comprehensive analysis of complete simulated
process chains. 相似文献