New method to determine FAO number of maize, Zea mays L.

FAO numbers are generally calculated from the grain moisture at harvest, which has decreased substantially in recent decades. In many countries maize is now harvested with a grain moisture of around 20 %. However, the lower the grain moisture at harvest, the smaller the difference in grain moisture between the maturity groups and/or individual hybrids. The reliability of grain moisture measurements has not improved parallel to the decline in the differences between hybrids, making it difficult to determine the maturity dates of the hybrids reliably. A new method has been elaborated to solve this problem and has been successfully used for the last two years in official trials in Hungary. The new method has several advantages: (a) more maturity parameters are taken into consideration, so the evaluation of more data improves reliability, (b) regression between the maturity parameters and the FAO number is calculated using several standards, thus reducing the effect of the G x E interaction and the experimental error. As a result, the annual fluctuation in the FAO number for each 1 % grain moisture is reduced

Simulation of a research reactor reactivity transient with deterministic and GPU-assisted Monte Carlo reactor kinetics codes

Reactor kinetic codes are crucial in safety assessment. Validating spatial and high temporal resolution kinetic solvers without thermal feedback is problematic as measurements seldom involve detailed spatial and fine temporal resolution. Benchmarking of deterministic codes thus often resorts to code-to-code comparison against Monte Carlo codes, which can only recently treat direct time dependence. In this paper, we have attempted to compare results from the GUARDYAN directly time-dependent Monte Carlo code and the SEnTRi transient driver developed for the PARTISN deterministic transport code to low power transient measured at the BME Training Reactor. Code-to-measurement comparisons were successful, despite a major uncertainty in the actual timing of the reactivity insertion and withdrawal originating from the instrumentation of the pneumatic rabbit system. Code-to-code comparisons concluded that time dependence was correctly implemented in both GUARDYAN and SEnTRi; furthermore, a hypothetical scenario was set up involving an instantaneous insertion of a negative reactivity into the BME TR core in order to compare spatially and temporally dependent fluxes. The simulations demonstrated the appearance of higher-order modes, and results showed a relatively good match, although fidelity of the comparison could be further improved by reducing the statistical uncertainty of the results provided by GUARDYAN

Mycotoxin contamination of maize (Zea mays L.) samples in Hungary, 2012–2017

Mycotoxin contamination of maize often raises risks for human and animal health. The most frequently detected mycotoxins in maize are trichothecenes, fumonisins, and aflatoxin. A total number of 17,011 maize samples were tested by SGS for their mycotoxin content between 2012 and 2017. The toxin results clearly show that the southern areas of the country had higher levels of toxin contamination than the average. According to the dataset, aflatoxin contamination has become regular but the appearance of fumonisins was also more frequent. Deoxynivalenol toxin accumulation in crops can also reach dangerous levels under favorable ecological conditions. The fluctuation between years and regisons is decisively shaped by the weather conditions. However, the two pathogens with less virulence (Fusarium verticillioides and Aspergillus flavus) must be taken into account and the contribution of insect pests. 72.63% of the total fumonisin concentration was defined as fumonisin B1, 20.34% as fumonisin B2, and 7.03% as fumonisin B3. The correlations between the three fumonisins analogs were higly significant (P = 0.001), and correlation coefficient varied between 0.961 and 0.998 across the six years of evaluation. This is the first complex evaluation of deoxynivalenol, fumonisin, and aflatoxin contamination of maize samples in Hungary

Lepidocrocite-like structure of the TiO2 monolayer grown on Ag(100)

Titanium oxide ultrathin films were grown on Ag(100) by evaporation of titanium in an O2 atmosphere. The growth of the oxide films was monitored by means of XPS. The Ti2p XPS spectra indicate the formation of films with a TiO2 stoichiometry in the whole range of coverages studied here. The STM results show that titania films appear to grow as islands of uniform thickness up to the completion of the first layer. Up to the formation of one complete monolayer, a (5 1) LEED pattern is observed. This pattern can be interpreted as a coincidence mesh and the lattice parameters of the oxide layer are very close to those of TiO2 films with a lepidocrocite-like structure. However, the STM images show a long-range coincidence between the periodicity of the oxide film and that of the substrate along the short side of the oxide unit cell revealing that this lattice parameter is not exactly equal to that of the substrate. Above the monolayer coverage, additional spots become visible in the LEED pattern which can be interpreted in terms of the unit cell of rutile (110). The structural determination was carried out for the monolayer of titania by means of XPD and LEED intensity analysis. The results of these investigations demonstrate that the titania monolayer has a lepidocrocite-like structure. The DFT calculations carried out for the titania monolayer show the higher stability of the lepidocrocite structure with respect to other structures derived from crystallographic planes of bulk TiO2 phases. Moreover, these calculations allow us to determine the oxide–substrate interface energy as well as to clarify the effect of the strain on the stability of the oxide layer

Diphosphetes-substituent stabilized ring systems

Bertrand G, Eisfeld W, Nyulaszi L, Reau R, Regitz M, Szieberth D. Diphosphetes-substituent stabilized ring systems. JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2. 2000;(11):2324-2327