Syngas production from gasification of high sulfur fuel oil using a CO2 sorbent

Hydrothermal gasification is a thermochemical; process that operates at a temperature range of 800-1000 C, in order to convert solid and liquid feedstocks into chemicals or clean gaseous fuel known as syngas. In this research, an Aspen plus model of heavy oil was developed to investigate the effect of operating conditions and a CO₂ sorbent (CaO) on gas composition and gasification efficiencies. An increase in CaO/F ratio from 0.5 to 1.0 greatly reduced amount of produced CO₂ and increased H₂ due to positive performance of carbonation reaction in conversion of CO₂ to CaCO₃. Carbon Conversion Efficiency (CCE) initially increased by raising CaO/F, and then it is relatively decreased by a further increase in CaO/F.     

Investigation of the transient electromagnetic processes and forcesin metallic environments of large superconducting magnets by anoptimized finite element approach

The stellarator Wendelstein 7-X is a steady state fusion experiment being built by the Max-Planck-Institute for Plasma Physics. The magnetic fields which are needed to enclose the plasma are to be supplied by superconducting coils. The steel plasma vessel and a helium cooled heat radiation shield are located between the coil system and the plasma space. Eddy currents are induced in these metal structures during an emergency discharge of the magnet system. The calculation of their effects-force density and heating-is, due to the complex geometry of the system, not possible neither with analytical tools nor by a complete modeling with conventional methods. Therefore, the new modeling method presented here, which is based on the FEM, was developed. In this method the spatial distribution of the magnetic vector potential A(r) is calculated. This calculation is done by a program based on the general Biot-Savart's law. Afterwards the calculated vector potential is given, with the help of the method of the Lagrange multipliers, in time varying form at every node. With the help of these calculations, suitable measures can be taken to reduce the eddy currents and the resulting forces in the cooling shield     

Novel electrochemical biosensing platform using self-assembled peptide nanotubes

Here we describe a novel electrochemical biosensing platform based on biocompatible, well-ordered, self-assembled diphenylalanine peptide nanotubes. Voltammetric and time-based amperometric techniques were applied to demonstrate the ability of the peptide nanotubes to improve the electrochemical parameters of graphite electrodes. The findings clearly show that this novel class of peptide nanotubes provides an attractive component for future electroanalytical devices.     

Preparation,characterization and in vitro biological response of simultaneous co-substitution of Zr+4/Sr+2 58S bioactive glass powder

In the present study, structure of zirconium-containing bioactive glass (58S-BG (Zr-BG)) with optimal fixed Zr content (5 mol.%) was modified by incorporation of strontium (Sr). These Zr and Sr-containing BGs (ZS-BGs) were synthesized by sol-gel method and substitution of Ca with modifier ions (Sr content = 0, 3, 6, 9, and 12 mol.%). The results obtained from characterization by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), and energy-dispersive X-ray spectroscopy (EDS) techniques from surface of all the ZS-BGs revealed formation of hydroxyapatite (HA) after 7 days of immersion in the simulated body fluid (SBF) solution. Evaluation of changes in the SBF solution, by monitoring pH variations and ions? concentration, was in agreement with the results of morphological and structural investigations. The in-vitro biological function of synthesized BGs was studied through (MTT) assay and alkaline phosphatase (ALP) activity analysis. The results showed that all the specimens significantly stimulated proliferation and viability of MC3T3 osteoblast-like cells. Furthermore, antibacterial studies confirmed less resistance of methicillin-resistant Staphylococcus aureus (MRSA) bacteria against ZS-BGs. Eventually, the results of in-vitro bio-analysis were clarified and confirmed by two cell staining techniques of Live/Dead and Dapi/Actin. This confirmation was achieved by observing the increased quantity of live cells and their nuclei as well as the decreased number of dead cells after co-culturing with all ZS-BGs.     

An image steganography method based on integer wavelet transform

This paper presents a novel approach for Image steganography based on Integer Wavelet Transform. In this method, the cover image is mapped to a specific frequency domain. Then in the obtained frequency domain, edge coefficients are classified based on their MSBs. The suggested method prevents changes in MSB in a way that receiver can extract the information without any mistakes. Considering the preformed classification, secret bits will be embedded in the frequency coefficients and then with the use of inverse transformation, stego image will be obtained. The most important features that our work obtained are good adaptation with human vision system and retrieval of data without error. Simulation results show that our proposed method has a good adaptation with human vision system (HVS) and outperforms in terms of PSPNR factors over recently published works.     

Cerium oxide/SnO2-based semiconductor gas sensors with improved sensitivity to CO

SnO₂-based semiconductor gas sensors have been successfully fabricated and tested for detecting carbon monoxide and methane. The sensitivity and selectivity of the sensors are tailored by incorporation of different additives such as platinum and cerium oxide. While platinum enhances the sensor response to CH₄, ceria suppresses its sensitivity in favor of carbon monoxide. The effect of operating temperature on the performance of sensors is reported. Addition of 10% cerium oxide in the SnO₂ sample leads to an insignificant response to methane even at an elevated temperature of 450°C, while its response to CO remains intact.     

Terror management and adults' attachment to their parents: The safe haven remains.

Six studies examined the role of young adults' parental attachment in terror management. Studies 1-3 revealed that activating thoughts of one's parent in response to mortality salience (MS) reduced death-thought accessibility and worldview defense and increased feelings of self-worth. Studies 4-5 demonstrated that MS led to greater ease of recalling positive maternal interactions and greater difficulty recalling negative interactions, and increased attraction to a stranger who was described as being similar to one's parent. If reliance on parents for terror management purposes reflects the operation of attachment mechanisms, then such effects should vary on the basis of an individual's attachment style. Study 6 demonstrated that, after MS, insecure individuals were more likely to rely on relationships with their parents, whereas secure individuals were more likely to rely on relationships with romantic partners. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sense of coherence, coping strategies, and test anxiety as predictors of test performance among college students.

The study tested sense of coherence (SOC; Antonovsky, 1987), coping strategies, and test anxiety as predictors of test performance in 216 1st-year undergraduates. The students attended 3 obligatory courses and completed inventories assessing SOC, coping, and test anxiety during the final session of the 2nd semester; their grades on the final examination were recorded. The results showed SOC to be negatively related to test anxiety, whereas emotion-focused coping and avoidance were positively related to it. Problem-focused coping contributed positively to performance on the test, and avoidance coping adversely affected test grades. The data suggest that test anxiety is minimally associated with performance grades, and the 2 measures are related somewhat differentially to coping strategies and SOC. (PsycINFO Database Record (c) 2010 APA, all rights reserved)