Three-dimensional h-adaptivity for the multigroup neutron diffusion equations

Adaptive mesh refinement (AMR) has been shown to allow solving partial differential equations to significantly higher accuracy at reduced numerical cost. This paper presents a state-of-the-art AMR algorithm applied to the multigroup neutron diffusion equation for reactor applications. In order to follow the physics closely, energy group-dependent meshes are employed. We present a novel algorithm for assembling the terms coupling shape functions from different meshes and show how it can be made efficient by deriving all meshes from a common coarse mesh by hierarchic refinement. Our methods are formulated using conforming finite elements of any order, for any number of energy groups. The spatial error distribution is assessed with a generalization of an error estimator originally derived for the Poisson equation.Our implementation of this algorithm is based on the widely used Open Source adaptive finite element library deal.II and is made available as part of this library's extensively documented tutorial. We illustrate our methods with results for 2-D and 3-D reactor simulations using 2 and 7 energy groups, and using conforming finite elements of polynomial degree up to 6.     

Pyrazolonderivate. IV [9]. Zur Tautomerie und Stereochemie von 4-Aminomethylen-Δ2-pyrazolinonen-(5)

Pyrazolone Derivatives. IV. Tautomerism and Stereochemistry of 4-Aminomethylene-Δ²-pyrazolinones-(5) Tautomerism and stereochemistry of compounds of type 1 were investigated by ¹H-n.m.r.- and i.r.-spectroscopy. Dynamic ¹H-n.m.r. study with ¹⁵N-labelled compounds shows, that 1 exist in solution as 4-aminomethylene-Δ²-pyrazolinones-(5) with strong intramolecular hydrogen bonds. Compared to 4-unsubstituted Δ²-pyrazolinones-(5) polar solvents do not change the tautomeric equilibrium of 1 . The N-aryl-substituted compounds have a higher NH-acidity than N-alkyl-substituted derivatives. In crystalline state the N-alkyl-substituted compounds 1g, h exist in the E-configuration as 4-aminomethylene-Δ²-pyrazolinones-(5) with intermolecular hydrogen bond. At higher temperatures or in solution the Z-isomer is formed spontaneously.     

Diamine oxidase supplementation improves symptoms in patients with histamine intolerance

Food Science and Biotechnology - Histamine intolerance (HIT) is thought to be caused by a disproportionate amount of histamine in the body. The enzyme diamine oxidase (DAO) is considered for the...     

Analysis of the Processing-Pressure Dependent Refractive Index of Polycarbonate by Transmission Measurements of Glass-Filled Specimen

In this study, the influence of pressure during processing on the refractive index (RI) of polycarbonate (PC) was investigated by transmission measurements on glass-filled samples with a spectrometer. In order to isolate the pressure dependence of the RI from other influencing parameters such as cooling rate, orientation and stress states, the samples were prepared in a pressure-specific volume-Temperature (pvT) instrument under constant cooling rate and temperature history and without shear effects. Subsequently, the RI was determined at the intersection of the dispersion curves of the glass and the polymer by evaluating the wavelength of the maximal transmission of the samples. The mean RI over the entire cross section of the sample is determined by the transmission measurements without complex sample preparation. The investigations show that the RI of PC increases by 3.26 E-6 per bar with increasing pressure. POLYM. ENG. SCI., 60:512–516, 2020. © 2019 The Authors. Polymer Engineering & Science published by Wiley Periodicals, Inc. on behalf of Society of Plastics Engineers.     

Identification of benzalkonium chloride in food additives and its inefficacy against bacteria in minced meat and raw sausage batters

There is a growing market for 'natural' food preservatives though their active ingredients are poorly known. We analysed four such additives, Bacterin, Protecta One, Protecta Two and Protecta Three, marketed as effective preservatives for meat products on the basis of salts and extracts of 'natural herbs'. Their ingredients were separated by HPLC and the structures of the antimicrobially active components were determined by mass spectrometry. The products contained the disinfectant benzalkonium chloride, an antimicrobial quaternary ammonium compound, as the only active principle. HPLC methods are reported for the analysis of benzalkonium chloride in such products and in meat. Bacterin and Protecta One, as well as pure benzalkonium chloride in equivalent concentrations, did not show antibacterial effects against meat-relevant pathogens in minced meat and raw sausage batter. Because benzalkonium chloride is not a permitted food additive, and is not effective as a preservative in meat, the public should be cautioned against such products alleged to contain 'natural herb extracts'.     

Ein Beitrag zur Biosynthese amylosereicher Erbsenstärken

Contribution to the Biosynthesis of High-amylose Pea Starches Biosynthesis of starch is a complex process but few details are still unknown. This paper describes an investigation upon pea starch biosynthesis. Peas as a source of starch offer two qualities, a pea starch with 40% amylose content (smooth pea starch) and a pea starch with more than 60% amylose content (wrinkled pea starch). Samples for analysis were taken during growth. According to the quantitative determination of starch and amylose the accuracy of amylose detection was tested. Furthermore a qualitative analysis was carried out by molecular weight estimation of the starch. Both kinds of peas showed a high amylose synthesis during the last few days of growth, whereas amylopectin synthesis was highly in earlier stages. Wrinkled peas have shown only little synthesis activity of amylopectin during maturity. Therefore the amylose content of these peas was higher, instead of equal amylose synthesis quotas of both smooth and wrinkled peas.