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Abstract According to an estimate, 30% to 40%, of global fruit are wasted, leading to post harvest losses and contributing to economic losses ranging from $10 to $100 billion worldwide. Among, all fruits the discarded portion of oranges is around 20%. A novel and value addition approach to utilize the orange peels is in nanoscience. In the present study, a synthesis approach was conducted to prepare the metallic nanoparticles (copper and silver); by utilizing food waste (Citrus plant peels) as bioactive reductants. In addition, the Citrus sinensis extracts showed the reducing activity against metallic salts copper chloride and silver nitrate to form Cu-NPs (copper nanoparticles) and Ag-NPs (Silver nanoparticles). The in vitro potential of both types of prepared nanoparticles was examined against plant pathogenic bacteria Erwinia carotovora (Pectobacterium carotovorum) and pathogens effect on human health Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Moreover, the in vivo antagonistic potential of both types of prepared nanoparticles was examined by their interaction with against plant (potato slices). Furthermore, additional antipathogenic (antiviral and antifungal) properties were also examined. The statistical analysis was done to explain the level of significance and antipathogenic effectiveness among synthesized Ag-NPs and Cu-NPs. The surface morphology, elemental description and size of particles were analyzed by scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy and zeta sizer (in addition polydispersity index and zeta potential). The justification for the preparation of particles was done by UV–Vis Spectroscopy (excitation peaks at 339 nm for copper and 415 nm for silver) and crystalline nature was observed by X-ray diffraction. Hence, the prepared particles are quite effective against soft rot pathogens in plants and can also be used effectively in some other multifunctional applications such as bioactive sport wear, surgical gowns, bioactive bandages and wrist or knee compression bandages, etc.

Reverse Osmosis (RO) process is being engaged to yield fresh water from brackish water sources. However, the RO process is characterized by its high specific energy consumption (SEC) owing to high-pressure pumps. The current study focuses on reducing the SEC of the brackish water RO desalination plant using model-based optimization practice. The inlet conditions of RO process such as the feed pressure, flow rate (individual membrane module and total plant) and temperature, have a substantial influence on the performance indicators namely, water productivity, product concentration and SEC. Therefore, the optimisation of this study has been directed to determine optimal inlet conditions within feasible limits to minimise SEC. Arab Potash Company (APC) brackish water RO desalination plant has been considered as the case study. The optimal inlet conditions have resulted in a significant energy saving of 27.97% depending on the set of decision variables being considered at a fixed brackish water feed concentration. [ABSTRACT FROM AUTHOR]

The structural and electronic properties of zinc clusters (Znn) for a size range of n = 2–15 are studied using density functional theory. The particle swarm optimization algorithm is employed to search the structure and to determine the ground-state structure of the neutral Zn clusters. The structural motifs are optimized using the density functional theory approach to ensure that the structures are fully relaxed. Results are compared with the literature to validate the accuracy of the prediction method. The binding energy per cluster is obtained and compared with the reported literature to study the stability of these structures. We further assess the electronic properties, including the ionization potential, using the all-electron FHI-aims code employing G0W0 calculations, and the G0W0Г0(1) correction for a few smaller clusters, which provides a better estimation of the ionization potential compared to other methods.

Background: A new coronavirus called SARS-CoV-2 was identified in Wuhan, China in December 2019. SARS-CoV-2 spread very rapidly, causing a global pandemic: Coronavirus Disease 2019 (COVID-19). A few pharmaceutical companies and pathologists have been trying to put forward a cure in the form of a vaccine but in vain. It has been reported that the universal BCG vaccination is effective in preventing and reducing severity of COVID-19. Materials and Methods: A pilot study was conducted on a Pakistani population using a validated survey. A questionnaire acquiring data regarding the BCG vaccination as well as COVID-19 status and symptoms experienced was generated using Google Forms. Statistical analysis was performed using SPSS version 23. Simple descriptive analysis was conducted to assess the correlation between the universal BCG vaccination and COVID-19. Results: This pilot study consisted of 50 participants who were suffering or had suffered from COVID-19, 39 of which were BCG vaccinated. Statistical analysis revealed that there is no significant correlation between universal BCG vaccination and COVID-19. Conclusion: Universal BCG vaccination has shown to have no significant impact on COVID-19. Further research including a bigger sample size is needed to support or oppose this finding. [ABSTRACT FROM AUTHOR]

A change in the composition and dopant content of selective atoms in a material leads to their new desired properties by altering the structure, which can significantly improve the performance of relevant devices. By acknowledging this, we focused on characterizing the optoelectronic and structural properties of cadmium-substituted zinc selenide (Zn1-xCdxSe; 0 ≤ X ≤ 1) semiconductors using density functional theory (DFT) within the generalized gradient approximation (GGA), EV-GGA, and mBJ approximations. The results proved the cubic symmetry of the investigated materials at all Cd concentrations (0, 0.25, 0.50, 0.75, and 1). Although a linear surge in the lattice constant is observed with the change in Cd content, the bulk modulus exhibits a reverse trend. These materials are observed to be direct bandgap semiconductors at all Cd concentrations, with a decrease in electronic bandgap from 2.76 eV to 1.87 eV, and have isotropic optical properties, showing their potential applicability as a blue-to-red display. The fundamental optical properties of the materials, such as optical conductivity, reflectance, refractive index, absorption, and extinction coefficient, are also discussed. These outcomes provide a computational understanding of the diverse applications of Zn1-xCdxSe semiconductors in optoelectronic, photonic, and photovoltaic devices, particularly for a visible-range display.

A plentitude of research has analyzed citizens’ belief in conspiracy theories and its individual‐level correlates. Yet, the effects of (political) context factors on the causes and effects of individual belief in conspiracy theories are still neglected. However, such context should be especially relevant when it comes to the impact of one’s belief in conspiracy theories on one’s political preference. In this article, we argue that the communication of governmental actors exerts a moderating influence on the link leading from a belief in conspiracy theories to political attitudes. In a nutshell, the belief in conspiracy theories should make citizens less likely to distrust their government—and the political system in general—in contexts where these theories are shared or at least publicly represented by governmental actors. Using two original data sets with data from Germany, Poland, and Jordan (Study 1) and data from Germany, Poland, Sweden, and France (Study 2), we test our argument based on an overall sample of about 10,000 cases. Our results indicate that higher degrees of generic conspiracy theories beliefs are associated with higher levels of political distrust across countries. Yet, confirming our argument, such an effect takes place less strongly in those countries in which governmental actors use conspiracy theories as a political communication strategy.

Abstract: Reverse osmosis (RO) is becoming one of the most promising technologies used in wastewater treatment because it offers high rate of contaminant rejection and lower energy consumption in comparison with other thermal treatment processes. Earlier research by the same authors in respect of a distributed 1‐dimensional mathematical model for a single spiral‐wound RO membrane module based on the solution–diffusion model has been used in this paper to simulate the rejection of N‐nitrosodimethylamine (NDMA) from wastewater in a series of 7 RO elements full‐scale treatment plant. First, the applicability of this model has been evaluated using a simulation study, and the results have been compared against experimental data gathered from the literature for a given plant. Second, further simulation and analysis studies are carried out to assess the performance of the plant for NDMA rejection and recovery rate under different operating conditions of feed pressure, flow rate, and concentration. For the studied RO configuration, it is concluded that a maximum of 55.1% NDMA rejection can be achieved, which confirms the remaining issue of lower NDMA rejection. [ABSTRACT FROM AUTHOR]

Abstract Various concentrations of Mg-doped ZnO nanorods (NRs) were prepared using co-precipitation technique. The objective of this study was to improve the photocatalytic properties of ZnO. The effect of Mg doping on the structure, phase constitution, functional groups presence, optical properties, elemental composition, surface morphology and microstructure of ZnO was evaluated with XRD, FTIR, UV–Vis spectrophotometer, EDS, and HR-TEM, respectively. Optical absorption spectra obtained from the prepared samples showed evidence of blueshift upon doping. XRD results revealed hexagonal wurtzite phase of nanocomposite with a gradual decrease in crystallite size with Mg addition. PL spectroscopy showed trapping efficiency and migration of charge carriers with electron–hole recombination behavior, while HR-TEM estimated interlayer d-spacing. The presence of chemical bonding, vibration modes and functional groups at the interface of ZnO was revealed by FTIR and Raman spectra. In this study, photocatalytic, sonocatalytic and sonophotocatalytic performance of prepared NRs was systematically investigated by degrading a mixture of methylene blue and ciprofloxacin (MBCF). Experimental results suggested that improved degradation performance was shown by Mg-doped ZnO NRs. We believe that the product synthesized in this study will prove to be a beneficial and promising photocatalyst for wastewater treatment. Conclusively, Mg-doped ZnO exhibited substantial (p

We have studied the behaviour of the cubic spinel structure of FeV2O4 under high-pressure by means of powder X-ray diffraction measurements and density-functional theory calculations. The sample was characterized at ambient conditions by energy-dispersive X-ray spectroscopy, Raman spectroscopy, and X-ray diffraction experiments. One of the main findings of this work is that spinel FeV2O4 exhibits pressure-induced chemical decomposition into V2O3 and FeO around 12 GPa. Upon pressure release, the pressure-induced chemical decomposition appears to be partially reversible. Additionally, in combination with density-functional theory calculations, we have calculated the pressure dependence of the unit-cell volumes of both the spinel and orthorhombic FeV2O4 crystal structures, whose bulk moduli are B0 = 123(9) and 154(2) GPa, respectively, finding the spinel FeV2O4 to exhibit the lowest bulk modulus amongst the spinel oxides. From experimental results, the same information is herein obtained for the cubic structure only. The Raman modes and elastic constants of spinel FeV2O4 have also obtained the ambient conditions.

The series of Bi2O2Se-Ag2Se composites were synthesized by two step solid state reaction followed by Spark plasma sintering. To optimize their thermal transport properties, different weight percent (wt. %) of silver i-e, 10%, 15% and 20%, was added. The room temperature X-ray diffraction (XRD) and high temperature XRD was used to investigate the crystalline phases, whereas the morphological study was conducted through FESEM. The thermal transport properties were evaluated from 323 K to 773 K, to study the effect of silver addition on thermal conductivity of all the composite samples. The reduced thermal conductivity of the composite with decreasing Ag contents is might be attributed to increase of the Ag2Se and Bi2O3 nano-inclusions in Bi2O2Se multi-phase-system that increased the phonon scattering regions and reduced the overall thermal conductivity significantly, up to 54 % for BA15SO as compared to that of BA20CO at 473 K.

In this paper, a review of materials selection methods is presented. It initially discusses the importance of materials selection in various fields of scientific study particularly in engineering design. Various tools and methods for the selection of materials are reviewed. These include materials handbook, materials data-bases, materials selection charts, artificial intelligence systems, and other computer-aided materials selection systems. [ABSTRACT FROM AUTHOR]