Analysis of Parameter Estimation Possibilities of the Thermal Contact Resistance Using the Laser Flash Method with Two-Layer Specimens

The paper presents a curve-fitting-based calculation of the thermal contact resistance and other parameters (absorbed energy and material properties) from laser flash measurements considering a two-layer specimen (aluminum substrate and stainless-steel film). Sensitivity analysis of different cases was used to examine the sensitivities of the unknown parameters: thermal contact resistance, absorbed energy, specific heat of the film, and thermal conductivity of the film. A nonlinear curve-fitting method was applied to perform the estimation of the unknown parameters using simulated measurements generated by the solution of the direct problem. An extensive analysis was performed to examine which parameters might be estimated simultaneously with the contact resistance for different noise levels of the simulated measurement. It was concluded that in the noiseless case all four unknown parameters can be estimated simultaneously with high accuracy. The noise has a significant effect on the accuracy of the parameter estimation, but even when a reasonable noise level is present, it is still possible to accurately estimate one or two parameters together with the thermal contact resistance.     

The effect of growth parameters on the intrinsic properties of large-area single layer graphene grown by chemical vapor deposition on Cu

We present a comprehensive study of the parameter space for single layer graphene growth by chemical vapor deposition on Cu. The temperature is the most widely recognized control parameter in single layer graphene growth. We show that the methane-to-hydrogen ratio and the growth pressure also are critical parameters that affect the structural perfection and the cleanliness of graphene. The optimal conditions for suppressing double and multilayer graphene growth occur near 1000 °C, 1:20 methane-to-hydrogen ratio, and a total pressure in the range from 0.5 to 1 Torr. Raman mapping of a 40 × 30 μm² area shows single layer domains with 5–10 μm linear dimensions. Atomic resolution imaging of suspended graphene by aberration corrected scanning transmission electron microscopy shows that the single layer graphene consists of areas of 10–15 nm linear dimensions and smaller patches of residual contamination that was undetected by other characterization methods.     

Arsenic removal from rice by washing and cooking with water

Two Hungarian and one Chinese rice samples were selected in order to establish the extractable arsenic content by washing and cooking in water in a ratio of 6:1, water:rice (cm³:g) by inductively coupled plasma sector field mass spectrometry (ICP-SF-MS). Total arsenic concentration of the Zhenshan 97, Risabell and Ko?röstáj-333 samples were 171.3 ± 7.1 ng g⁻¹, 116.0 ± 3.7 ng g⁻¹ and 139.0 ± 6.1 ng g⁻¹, respectively, which did not exceed the toxic limits established for As in Hungary (0.3 μg g⁻¹) or in China (0.7 μg g⁻¹). The predominant chemical form of As in the raw rice samples determined by on-line high performance liquid chromatography and ICP-MS was arsenite. Moreover, enzymatic hydrolysis with α-amylase + protease and microprobe focused sonication proved that arsenite could be removed in the highest extent by washing and cooking, meanwhile the main As form remaining in the cooked rice was As(V). Thus, it is recommended to prepare rice-containing dishes in abundant water, which should be discarded after washing and cooking. The results were validated with a NIST SRM 1568a.     

DUckCov: a Dynamic Undocking-Based Virtual Screening Protocol for Covalent Binders

Thanks to recent guidelines, the design of safe and effective covalent drugs has gained significant interest. Other than targeting non-conserved nucleophilic residues, optimizing the noncovalent binding framework is important to improve potency and selectivity of covalent binders toward the desired target. Significant efforts have been made in extending the computational toolkits to include a covalent mechanism of protein targeting, like in the development of covalent docking methods for binding mode prediction. To highlight the value of the noncovalent complex in the covalent binding process, here we describe a new protocol using tethered and constrained docking in combination with Dynamic Undocking (DUck) as a tool to privilege strong protein binders for the identification of novel covalent inhibitors. At the end of the protocol, dedicated covalent docking methods were used to rank and select the virtual hits based on the predicted binding mode. By validating the method on JAK3 and KRas, we demonstrate how this fast iterative protocol can be applied to explore a wide chemical space and identify potent targeted covalent inhibitors.     

Intermediates and isomers in the substitution of cobalt carbonyl hydride with tertiary phosphorous ligands

Mono- and disubstitution of HCo(CO)₄ with tertiary phosphines and phosphites was studied by IR and¹H-NMR spectroscopy. It was found that these substitutions proceed through phosphonium tetracarbonylcobaltate intermediates, leading to a mixture of isomers. The crystal and molecular structure of trans-HCo(CO)₃[P(O-p-C₆H₄Ph)₃] was determined by X-ray diffraction.GDR research fellow at the University of Veszprém.     

The mechanism of orientation in cold-drawn polyoxymethylene as revealed by crystallographic pole figures

The orientation mechanism of cold-drawn, partially crystalline polyoxymethylene (ULTRAFORM) samples was studied by performing wide angle X-ray scattering (WAXS) measurements. The anisotropic samples were prepared in uniaxial tensile tests around 130°C, in a temperature range between the glass transition and the melting point. The process of the plastic deformation is discussed for different degrees of anisotropy. The orientation distribution of the crystalline lamellae was qualitatively characterized by performing pole figure intensity calculations from the measured WAXS intensities. The degree of orientation was quantitatively described by calculating the orientation factors for the [100] normal vector of the unit cell. The texture of the necked samples with high orientation degrees was a mixture of axial and uniplanar-axial textures. An explanation for the formation of this kind of orientation is proposed assuming an influence of the sample geometry on the orientation process.     

Next Generation University Library Information Systems Based on Cooperative Learning

An integrated library information system is a resource planning system for a library, used to track resources owned, bills paid, orders made, and patrons who have borrowed. In our research, we focused on university library information systems (ULISs). We identified an important research question regarding their main limitation in offering intelligent help to the students in their documentation/learning. We identified the importance of the endowment of ULISs with artificial intelligence. In this article, we analyzed different aspects related to the presence of computational intelligence in ULISs and intelligence of ULISs. Finally, we proposed a complex next generation ULIS based on a hybrid cooperative learning, being able to offer an intelligent help for personalized learning of students. We defined some novel paradigms in the context of a novel kind of cooperative hybrid personalized learning, such as learning role and sub-role; and learning intelligence level.     

Comparison of Ozone-based and other (VUV and TiO2/UV) Radical Generation Methods in Phenol Decomposition

The degradation reaction kinetics and chemical mechanism of phenol decomposition by ozonation, TiO₂-photocatalysis and vacuum ultraviolet (VUV) photolysis were investigated. The concentration dependences of the aromatic and aliphatic intermediates and the TOC content were compared as a function of the phenol conversion. The concentration profiles and the TOC curves obtained with each method were very similar. The results suggest a similar chemical mechanism for the transformation of phenol irrespective of the starting active component (a positive hole on the surface of the catalysts, a VUV photon, ozone or the hydroxyl radical).     

UV-induced Decomposition of Ozone and Hydrogen Peroxide in the Aqueous Phase at pH 2–7

The photolysis of ozone and formation of hydrogen peroxide were investigated in solution of pH 2–7, in a 200 cm³ photoreactor in the incident photon flow range 9.6 x 10^?8 - 4.2 x 10^?7 einstein s^?1. The quantum yield of the primary photochemical reactions was measured in a direct way by suppressing the secondary radical reactions. The determined quantum yields of the photo-decompositions of ozone and hydrogen peroxide were 0.42 ± 0.042 ± 0.04 and 0.49 ± 0.04, respectively.

A correct mathematical treatment is given for calculation of the light absorption of the individual components of a multi-absorbent reaction mixture.

On the basis of the literature data and die present results, a probable chemical and reaction kinetic model was proposed to characterize the investigated reaction systems. Reaction kinetic simulations demonstrated that the model predicts a good fit to the measured data with the preferred literature rate constants, except that for the HO₃ radical decomposition reaction. A reasonable reduction of this rate coefficient value is in accordance with the latest published results.