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In This work, they made Bismuth oxide (Bi2O3-based) and zinc oxide (ZnO)–doped thin films using thermal evaporation. XRD confirms the phase geometries of monoclinic and (Bi2O3/ZnO) thin films. When ZnO is added, the average crystal size decreases from 17.35 to 8.67 nm. Structures have been examined using Fourier transform infrared (FT-IR) and scanning electron microscopy. The Fourier transform infrared (FT-IR) investigation found no chemical reactions in the (Bi2O3/ZnO) thin films. A scanning electron microscopy (SEM) examination of the (Bi2O3/ZnO) thin films showed uniform results. Increased ZnO doping reduces the diameter by 67.6%, from 34.20 to 11.06 nm. The optical properties of the (Bi2O3/ZnO) thin film material are examined in this work. It has been shown that (Bi2O3/ZnO) concentration increases absorbance and absorption coefficients. The transmittance and energy band gaps decreased as ZnO concentrations with significant UV light absorption increased. The direct current (D.C) electrical conductivity of (Bi2O3/ZnO) thin films is positively correlated with (ZnO) nanoparticle concentration and temperature, according to experiments. At the same time, the activation energy falls with (ZnO) nanoparticle concentration, given a fixed quantity. The gas sensor showed 96.4% sensitivity to H2S gas at 200 °C. The experiment employed 50 ppm H2S. Finally, the (Bi2O3/ZnO) thin film examination reveals their structural characteristics and conductivity. These results may be helpful in UV sensors and gas sensors. The utilisation of (Bi2O3/ZnO) thin film gas sensor has demonstrated significant potential as a viable option for gas sensing systems, primarily attributed to the enhanced surface area achieved by the application of metal oxide catalysts. The present study also discusses the mechanisms implicated in the augmentation of gas response and the broadened range of applications.

In this present work, bismuth oxide (based on Bi2O3) and zinc oxide (ZnO-doped) thin films were produced by thermal evaporation (RT) method on 50-nm-thick glass substrates and annealed at 573 K. SEM showed that the (Bi2O3/ZnO) nanoparticles were evenly dispersed throughout when the ZnO doping concentration was increased. The actual result of the optical characteristics of (Bi2O3/ZnO) showed that (extinction coefficient, refractive index, real part and imaginary part of the dielectric constant) increase with increasing concentrations of ZnO nanoparticles. This behavior makes them excellent optical materials for photonics applications. The results of the D.C electrical characteristics show that the D.C electrical conductivity of the (Bi2O3/ZnO) nanocomposites increases with increasing nanoparticle (ZnO) concentrations and temperature. At the same time, the resistance and activation energy decrease with increasing nanoparticle (ZnO) concentrations. The measured gas sensor revealed a sensitivity to H2S of about 69.74% at 200 °C, decreasing to about 55.14% at 250 °C and 51.42% at 300 °C. Finally, the results of the structural and conductive characteristics of (Bi2O3/ZnO) thin films can be used in various nanoelectronics devices and gas sensors. Finally, the results expected that metal oxide nanostructures will prove to be the most effective building blocks for developing cutting-edge gas sensors. The effects of various doping’s on the morphology and crystal structure of ZnO materials are examined in depth in this article. This article provides sound advice for developing high-performance semiconductor oxide sensing materials based on zinc oxide (ZnO).

AbstractThe spread of fungal growth causes enormous economic, agricultural, and health problems for humans, such as Aspergillussp., which produce aflatoxins. Thus, the inhibition of aflatoxin production became a precious target. In this research, the thioesterase (TE) domain from Polyketide synthase enzyme was selected to employ the in silicodocking, using AutoDock Vina, against 623 natural compounds from the South African natural compound database (SANCDB), to identify potential inhibitors that can selectively inhibit thioesterase domain. The top ten inhibitors components were pinocembrin, typhaphthalide, p-coumaroylputrescine, dilemmaone A, 9-angelylplatynecine, 2,4,6-octatrienal, 4,8-dichloro-3,7-dimethyl-, (2e,4z,6e)-, lilacinobiose, 1,3,7-octatriene, 5,6-dichloro-2-(dichloromethyl)-6-methyl-, [r*,s*-(e)]-(-)- (9ci), lilacinobiose, 1,3,7-octatriene, 5,6-dichloro-2-(dichloromethyl)-6-methyl-, [r*,s*-(e)]-(-)- (9ci), 1,3,7-octatriene, 1,5,6-trichloro-2-(dichloromethyl)-6-methyl-, [r*,s*-(z,e)] and 9-angelylhastanecine and that depending on the lowest binding energy, the best chemical interactions and the best drug-likeness. The results of those components gave successful inhibition with the thioesterase domain. So, they can be used for inhibition and controlling aflatoxin contamination of agriculture crop yields, specially, pinocembrin which gave promising results.Communicated by Ramaswamy H. Sarma

A proton NMR method is described which enables rotational flow and viscosity measurements of low molecular weight ṉematic ḻiquid c̱rystals (NLC's). This is achieved by an extension of the common NMR field-cycling technique, namely by fast electronic switching of both the external magnetic field direction and strength. In thermodynamic equilibrium, the director of an NLC with positive diamagnetic anisotropy (Δχ> 0) orients parallel to the external magnetic field. Thus a change of this direction causes a reorientation process of the molecules to align to the new equilib­rium, which in low viscous systems in contrast to polymer liquid crystals is rather fast and hence requires fast field switching. We have studied systematically this response as a function of the initial field rotation angle 90 relative to the director for some homologous NLC's of the n-alkyl-cyano-biphenyl (nCB) series. It is shown that there exists a critical angle θcrin such a way that for θo < θcr, however (e.g. in the case of 5 CB θcris ≈ 85 degrees) the viscoelastic behaviour is more complicated because of a coupling between flow and director gradients. The analysis of the alignment process by the changes of the proton line spectra also allows to determine the Leslie viscosities α1, α2, α3, α4+ α5, and the average Frank elastic constant K̄ by a single measurement.

The reactions between 1,2‐, 1,3‐ or 1,4‐diols and SF4, which are carried out according to method A) using the diols (I), (IV), (IX) or (XI) as the substrates, proceed via substitution of a hydroxy group by a fluorine atom to give the fluoro derivatives (III), (VII)/(VIII), (X) or (XII) either directly or after work‐up of the fluorosulfites (cf.