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Abstract: To further expand the application of an artificial neural network in the field of neutron spectrometry, the criteria for choosing between an artificial neural network and the maximum entropy method for the purpose of unfolding neutron spectra was presented. The counts of the Bonner spheres for IAEA neutron spectra were used as a database, and the artificial neural network and the maximum entropy method were used to unfold neutron spectra; the mean squares of the spectra were defined as the differences between the desired and unfolded spectra. After the information entropy of each spectrum was calculated using information entropy theory, the relationship between the mean squares of the spectra and the information entropy was acquired. Useful information from the information entropy guided the selection of unfolding methods. Due to the importance of the information entropy, the method for predicting the information entropy using the Bonner spheres' counts was established. The criteria based on the information entropy theory can be used to choose between the artificial neural network and the maximum entropy method unfolding methods. The application of an artificial neural network to unfold neutron spectra was expanded. [Copyright &y& Elsevier]

A simple and efficient method for fabricating self‐standing Au/SiO2 hybrid nanorod arrays is demonstrated. Highly dispersed uniform Au NPs are immobilized on SiO2 nanorod arrays and show high catalytic activity for the direct formation of H2O2 from H2 and O2. [ABSTRACT FROM AUTHOR]

BACKGROUND The 7S and 11S fractions from soybean proteins have interesting high nutritional and excellent functional properties. The aim of this research was to improve the functional properties of soy proteins by studying the effect of bis(2-ethylhexyl) sodium sulfosuccinate ( AOT) reverse micelles on the conformation of the 7S and 11S globulins using Fourier transform infrared and X-ray diffraction spectroscopy. RESULTS Fourier transform infrared revealed that the intensity of the 7S and 11S globulin bands from AOT reverse micelle extraction at 1600-1700, 1480-1575, 1220-1300, 3330, 1448 and 1395 cm−1 was higher than from aqueous buffer. X-ray diffraction data showed that the intensities of 7S globulin using two extraction methods at 2 θ about 10° were significantly different ( P < 0.05), about 22° slightly increased. The intensities of 11S globulin at 2 θ about 10° and 22° were similar. The average distance between particles ( dhkl) for 7S globulin with aqueous buffer extraction at 2 θ about 10° was greater than AOT reverse micelle extraction. CONCLUSION This study showed the potential of reverse micelles as a protocol for extracting the 7S and 11S globulins for analytical purposes. The results represent a new avenue for determining the structures of the 7S and 11S globulins. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Developing efficient catalytic processes to convert methane into useful feedstocks relies critically upon devising new coupling processes that use abundant, thermodynamically 'mild' oxidants together with selective catalysts. We report here on elemental sulfur as a promising 'soft' oxidant for selective methane conversion to ethylene over MoS2, RuS2, TiS2, PdS and Pd/ZrO2 catalysts. Experiments and density functional theory reveal that methane conversion is directly correlated with surface metal-sulfur bond strengths. Surfaces with weakly bound sulfur are more basic and activate methane C-H bonds more readily. In contrast, experimental and theoretical selectivities scale inversely with surface metal-sulfur bond strengths, and surfaces with the strongest metal-sulfur bonds afford the highest ethylene selectivities. High CH4/S ratios, short contact times and the provision of a support maximizes the coupling of CHx intermediates and selectivity to ethylene, because these conditions yield surfaces with stronger metal-sulfur bonding (for example, Pd16S7), which suppresses the over-oxidation of methane. [ABSTRACT FROM AUTHOR]

Background: Histone ubiquitination modification is emerging as a critical epigenetic mechanism involved in a range of biological processes. In vitro reconstitution of ubiquitinated nucleosomes is pivotal for elucidating the influence of histone ubiquitination on chromatin dynamics. Results: In this study, we introduce a Non-Denatured Histone Octamer Ubiquitylation (NDHOU) approach for generating ubiquitin or ubiquitin-like modified histone octamers. The method entails the co-expression and purification of histone octamers, followed by their chemical cross-linking to ubiquitin using 1,3-dibromoacetone. We demonstrate that nucleosomes reconstituted with these octamers display a high degree of homogeneity, rendering them highly compatible with in vitro biochemical assays. These ubiquitinated nucleosomes mimic physiological substrates in function and structure. Additionally, we have extended this method to cross-linking various histone octamers and three types of ubiquitin-like proteins. Conclusions: Overall, our findings offer an efficient strategy for producing ubiquitinated nucleosomes, advancing biochemical and biophysical studies in the field of chromatin biology. [ABSTRACT FROM AUTHOR]

Information on source neutrons is crucial to neutronic experiments that use deuterium–tritium (D–T) neutron generators. The quality of source neutron information affects the reliability of the comparative analysis between experimental and simulated results. Distribution of tritium in the tritide target is a necessary input data for the D–T source neutron analysis. However, due to the lack of an in-situ method, the current parameter analysis of neutron source can only use hypothetical tritium distribution data, which introduces extra uncertainty to the results of modeled neutron source. In this study, we present an in-situ method for profiling tritium in the tritide target based on the measured associated alpha spectra. The developed tritium profiling method can be embedded into the source neutron modeling method so as to obtain the parameters of neutron source. The proposed methodology is validated by measuring the differential spectra of D–T source neutrons at 0°, 45°, 90°, 135°, using the time of flight (TOF) method. At these angles, the neutron intensity ratios of the simulation to the experiment are 1.04 ± 4%, 1.08 ± 2%, 0.90 ± 2%, 1.04 ± 3%; while the difference of the peak energy between measured and calculated spectra are 0.05 ± 0.01 MeV, 0.12 ± 0.04 MeV, 0.24 ± 0.06 MeV, and 0.25 ± 0.01 MeV, respectively. It is found that measured and simulated results are in good agreement in terms of neutron intensity and peak energy; and that further investigation is required to understand the discrepancy on the differential spectra obtained in simulation and measurement. [ABSTRACT FROM AUTHOR]