RESUMO
The results of experimental studies of the valence electronic structure of tetrahydrofuran employing He I photoelectron spectroscopy as well as Electron Momentum Spectroscopy (EMS) have been reinterpreted on the basis of Molecular Dynamical simulations employing the classical MM3 force field and large-scale quantum mechanical simulations employing Born-Oppenheimer Molecular Dynamics in conjunction with the dispersion corrected ωB97XD exchange-correlation functional. Analysis of the produced atomic trajectories demonstrates the importance of thermal deviations from the lowest energy path for pseudorotation, in the form of considerable variations of the ring-puckering amplitude. These deviations are found to have a significant influence on several outer-valence electron momentum distributions, as well as on the He I photoelectron spectrum.
Assuntos
Elétrons , Simulação de Dinâmica Molecular , Análise Espectral/métodosRESUMO
The results of experimental studies of the valence electronic structure of 1-butene by means of electron momentum spectroscopy (EMS) have been reinterpreted on the basis of molecular dynamical simulations in conjunction with the classical MM3 force field. The computed atomic trajectories demonstrate the importance of thermally induced nuclear dynamics in the electronic neutral ground state, in the form of significant deviations from stationary points on the potential energy surface and considerable variations of the C-C-C-C dihedral angle. These motions are found to have a considerable influence on the computed spectral bands and outer-valence electron momentum distributions. Euclidean distances between spherically averaged electron momentum densities confirm that thermally induced nuclear motions need to be fully taken into account for a consistent interpretation of the results of EMS experiments on conformationally flexible molecules.
RESUMO
Currently, sweet corn is considered an important crop due to its high sugar content and low starch content. Important sugars in sweet corn include sucrose, fructose, glucose, and maltose. The purpose of the present study was to use the yield indices of the eight examined sweet corn hybrids and the correlation of the yield indices together. Concentration is important for consumers in terms of yield indices. The research site was located at the Látókép Experimental Station of the University of Debrecen. The small plot experiment had a strip plot design with four replications. The previous crop was sweet corn; the plant density was 64 thousand/ha. The obtained result indicates that Biplot AMMI based on IPCA1 showed that the DB, NO, GS, and GB hybrids had stability and high performance in terms of yield indices. At the same time, fructose and glucose had stable parameters for the hybrids involved in the study. IPCA1 AMMI biplot showed that the ME hybrid had stability and high performance in terms of iron and zinc as well. IPCA2 AMMI biplot showed that DE, GB, and GS hybrids had stability and the highest performance on yield parameters in the scope of the research. Fructose, glucose, and sucrose had stable parameters on hybrids based on IPCA2. The DB and SE hybrids had desirable performance in Lutein and Zeaxanthin based on the biplot. The DE hybrid had a maximum performance on iron and zinc parameters.
Assuntos
Zea mays , Glucose , Ferro , Sacarose , Verduras , ZincoRESUMO
This study aimed to identify the best genotypes using the genotype × yield × trait (GYT) method. To investigate the relationships was performed between yield × traits in four regions of Karaj, Birjand, Shiraz and Arak in two cropping years in a randomized complete block design (RCBD) with three replications. The average grain yield in four regions and two years of the experiment was calculated as 5966 kg/ha, and GYT was obtained based on the multiplication of grain yield with different traits. Comparing the average effect of genotype × year in different environments showed that KSC703 and KSC707 hybrids are among the most productive hybrids among the studied genotypes in grain yield. By examining the correlation coefficients between yield × traits in the tested areas, Y × TWG with Y × GW, Y × NRE, Y × NGR and Y × EL, Y × ED with Y × NGR, Y × NRE with Y × GW and the combination of Y × GW with Y × GL had a positive and significant correlation in all regions. The correlation diagrams were drawn on the evaluated areas' data and showed the correlation of most compounds except Y × GT with each other. Based on the analysis of the main components, the first three components explained the greatest diversity in the population. They were named the component ear grain profile, grain thickness component and plant height profile component.
Assuntos
Grão Comestível , Zea mays , Grão Comestível/genética , Genótipo , Fenótipo , Zea mays/genéticaRESUMO
In this paper, a bio-sensing setup for investigating hepatitis B virus deoxyribonucleic acid (HBV DNA) diagnosis including rapid testing and field effect transistor (FET) in label free assay is proposed. The FET biosensor was fabricated by molybdenum doped ZnO nanowires (NWs) in easy method and cost-free approach. The materialized NWs were synthesized by physical vapor deposition (PVD) growth mechanism. The molybdenum dopant could bring about vacancy sites for DNA adsorption and electric charge transfer. The capability of the fabricated biosensor was evaluated by investigating the PCR-verified samples known as True Positive (TP), True Negative (TN), False Positive (FP) and False Negative (FN). The FET biosensor could materialize the clinical tests on samples TP, TN, FP and FN and could distinguish the clinical samples from each other. The designed biosensor showed more precision than the PCR-outcomes by exhibiting more sensitivity on labeled samples known as FN. This research has analytical and comparative study on fabricated biosensor performance. The achieved results show that the biosensor had significant response to samples which have not been carefully detected by PCR test. The fabricated biosensor showed high accuracy, precision, sensitivity, specificity and reproducibility for differentiating (TP), (TN), (FP) and (FN) samples from healthy and normal sample. The response sensitivity was calculated and biosensor showed a detection limit (LOD) of 1 pM. The biosensor demonstrated high response and satisfied signal in the concentration ranges from 1 pM to 10 µM.
Assuntos
Técnicas Biossensoriais , Óxido de Zinco , DNA , Vírus da Hepatite B/genética , Molibdênio , Reação em Cadeia da Polimerase , Reprodutibilidade dos TestesRESUMO
The gas-phase decomposition kinetics of isopropyl acetate (IPA) and its methyl, bromide and hydroxyl derivatives into the corresponding acid and propene were investigated using density functional theory (DFT) with the ωB97XD and M06-2x functionals, as well as the benchmark CBS-QB3 composite method. Transition state theory (TST) and RRKM theory calculations of rate constants under atmospheric pressure and in the fall-off regime were used to supplement the measured energy profiles. The results show that the formation of propene and bromoacetic acid is the most dominant pathway at the CBS-QB3 composite method, both kinetically and thermodynamically. There was a good agreement with experimental results. Pressures greater than 0.01 bar, corresponding to larger barrier heights are insufficient to ensure saturation of the measured rate coefficient when compared to the RRKM kinetic rates. Natural bond orbitals (NBO) charges, bond orders, bond indices, and synchronicity parameters all point to the considered pathways taking place via a homogenous, first-order concerted, as well as an asynchronous mechanism involving a non-planar cyclic six-membered transition state. The calculated data exhibit that the elongation of the Cα-O bond length and subsequent polarization of the Cα +δ O-δ bond is the rate-determining step of the considered reactions in the cyclic transition state, which appears to be involved in this type of reaction.