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In the present study, xylooligosaccharides (XOS) production was carried out using sorghum (Sorghum bicolor(L.)) xylan and xylanase from isolated Aspergillus fumigatesRSP-8 followed by evaluation of their prebiotic potential using Lactobacillussp. T-10. Isolated xylan revealed structural similarity to Birchwood xylan and is composed of xylose (89%) arabinose (6%) and glucose (5%). Xylanase enzyme produced by Aspergillus fumigatusRSP-8 revealed 43 kDa molecular weight with little β-glucosidase and depicted optimum activity of 1248 U/mL at pH 5.0 and temp 50 °C. Time-dependent XOS [(X2 (xylobiose) to X7 (xyloheptose)] production was noticed and differed from source to source. XOS production kinetics indicated that maximum XOS (8.4 g reducing sugar/L) was obtained in 12 h at 50 °C with 50 U/mL xylanase with 1.5% (w/v) sorghum xylan as substrate. The produced XOS promoted LactobacillusT-10 growth indicating its prebiotic potential. This study can provide useful insights into the processes required for further upscaling of agricultural biomass to nutraceutical product production and the industrial application potential of sorghum xylan.

Purpose: The world has faced various epidemic situations caused by different viruses such as SARS-Cov, MERS-Cov, Ebola and many more during the past few decades, SARS-Cov-2 (COVID-19) is the genetic variant of newly the discovered Coronavirus, which has been believed to spread from China during December 2019, which has created a catastrophic effect for the whole world. In the first quarter of 2020, the virus started to spread to different countries, in addition, the severity of cases, the mortality rate and the recovery rate varied between countries. In the Sultanate of Oman and different parts of the world, the COVID started to spike during the end of March 2020. In this research paper, COVID data for Gulf Cooperation Council (GCC) countries are extracted and analysis has been made based on different parameters. The analysis has been divided into two categories – the first part focuses on the total number of cases, the total number of recoveries and the total number of deaths and comparison has been made for different GCC countries, from these analyses, it gives a clear picture of the days of a particular month, which contributes to the increase of COVID cases. The second part focuses on finding out the indicators that are correlating with the COIVD-19 cases and deaths; it has been found that there is a very strong correlation between the total population and labour force of every GCC country with the corresponding COVID cases and deaths. Design/methodology/approach: The entire research steps involved starts with data collection, data pre-processing and data analysis. The analysis has been divided into two categories – the first part focuses on the total number of cases, the total number of recoveries and the total number of deaths and comparisons has been made for different GCC countries. The second part focuses on finding out the indicators that are correlating with COIVD-19 cases and deaths. Findings: It has been found that there is a very strong correlation between the total population and labour force of every GCC country with the corresponding COVID cases and deaths. Research limitations/implications: The data set considered is limited and can be extended further. Social implications: This research paper definitely provides a road map for practice, as this research provides details about the total number of active cases, death based on the days in different GCC countries. It has been observed that during the end of each month and during weekends, the total number of cases increases drastically, so by taking into consideration the governing bodies can impose a lockdown during these spike durations. In addition to it, the citizens and residents should make a practice to avoid or limit their movement during the spike durations, which was analysed by this research work. Originality/value: The idea is the own idea and not copied from any other source.

The study focuses on fabricating Al7075 metal matrix composites (MMC) with silicon carbide ceramic particles and various other solid lubricants for application in the development of piston. The composition of the casted specimen is 90 wt.% Al7075 alloy as well as 5 wt.% of SiC, which has to be kept as constant, and varying the type of the solid lubricants: graphite, hexagonal boron nitride (hBN), and molybdenum disulfide (MoS2) with 5 wt.%. Hybrid Al7075 composites are successfully fabricated through the stir casting process. The casted specimens are machined for the necessary testing as per the ASTM standards. The mechanical properties like tensile strength, compression strength, and hardness of the fabricated composites are evaluated by conducting experimental tests while the wear properties were evaluated via the pin-on-disc method. The results are compared to assess the best combination of solid lubricants for piston applications. The results indicate that Al7075 with 5 wt.% SiC and 5 wt.% graphite composite outperformed all other hybrid composites by evincing excellent mechanical and tribological properties; this might be due to the synergic effect of graphite with the Al7075 –SiC MMC.

Indian cherry (Cordia dichotomaForst.) is a medicinally important plant widely consumed as an indigenous remedy for several ailments in the India. Although it is widely used plant by the population, there are no studies on root proving these medicinal claims. The present study was designed to investigate antimicrobial, antimycobacterial and antioxidant activities of Cordia dichotomaForst. roots and in silico biological activities prediction using PASS. Methanolic extract was prepared and further fractions were obtained by liquid–liquid partitioning. Agar well diffusion assay and disc diffusion method were selected for antimicrobial activity. Antimycobacterial activity was estimated against Mycobacterium tuberculosis. For antioxidant activity, DPPH and hydrogen peroxide (H2O2) radical scavenging assay were employed. All the tested samples exhibited diverse pattern of sensitivity for tested strains. The value of MIC, MMC and MIC index showed that P. vulgarisand K. pneumoniawere the most sensitive for ME and CF, whereas A. fumigatesand V. myditiswere sensitive to CF and AF. Microorganism susceptible index was 100 for P. vulgarisand K. pneumoniabacteria, and A. fumigatesand V. myditisfungi. CF exhibited best activity against M. tuberculosiswith lowest MIC of 30 mg/ml and highest activity index of 0.85. Dose dependent antioxidant activity was observed in both the assay. This data provides evidence that Cordia dichotomaForst. roots have potent antibacterial, antimycobacterial, antioxidant, and moderate antifungal activity and a potential cure for infectious diseases like tuberculosis.

AbstractThe permeability characteristics of homogenous perforated plate have been estimated using measured pressure drops and velocities through pipe flow experiments. An empirical formula for coefficient of permeability is proposed for various values of porosity of plates, which is further used in a theoretical model to estimate the hydrodynamic characteristics of perforated plate, in terms of wave reflection and transmission. The empirical formula-based theoretical estimation of reflection and transmission coefficients is then validated with the experimental results obtained from wave tank tests, for single and double perforated vertical barriers.

From an ingenious methodology for obtaining monodispersity, digestive ripening has advanced to become an outstanding solution-based synthesis route to realizing various bimetallic heterostructures. This feature article attempts to provide an overview of the various facets of the codigestive ripening process and the array of heterostructures that could be achieved by this technique. We briefly discuss the mechanism of digestive ripening in the case of monometallic elements and use that understanding to elucidate the mechanism of the less well established codigestive ripening strategy for designing bimetallic nanostructures. The systems studied by our group in the past decade for the fabrication of diverse heterostructures are highlighted in this article. The exploitation of digestive ripening to realize monodisperse bimetallic nanostructures by several other groups is also featured. In addition to digestive ripening agents, the significance of tuning various reaction parameters and its consequences on the final structure and morphology have also been discussed. Additionally, efforts based on theoretical studies to gain insight into the factors which dominate the mechanism of the digestive ripening process have also been covered. This article is a contribution to the understanding of the codigestive ripening methodology and a demonstration of its tremendous potential in achieving the desired bimetallic heteronanostructures.

Digestive ripening (DR) is a postsynthetic protocol for the transformation of a colloid consisting of polydisperse metal nanoparticles (NPs) into a colloid composed of nearly monodisperse metal nanoparticles. This process is brought about by the digestive ripening agent, typically an organic ligand with a long alkyl chain at one end and a functional group at the other, at the boiling point of the solvent in which it is carried out, requiring long periods of time. In this work, digestive ripening of polydisperse Ag and Au nanoparticles brought about by ionic liquids (ILs) under very mild conditions (∼273 K, ∼30 min) to obtain nearly monodisperse nanoparticles has been demonstrated. Herein, the ionic liquid plays a dual role, as a digestive ripening and a stabilizing agent for the nanoparticles. Ionic liquid-assisted digestive ripening under such mild temperatures and short period of time has hitherto not been reported.

Co-digestive ripening of two distinct metal nanoparticles is an exceptional method for the colloidal synthesis of core–shell heterostructures. In this report, a detailed investigation of the underlying mechanism by which surfactant molecule assisted interatomic transfer between two metal nanoparticles occurs has been described using gold/silver as a model system. Core–shell nanoparticles with gold in the core and silver in the shell in the size regime of 6.9 ± 1.8 nm were obtained by conducting the codigestive ripening of polydispersed particles of Au–pentanone and Ag–pentanone colloids in the presence of hexadecylamine as a capping agent used in the molar ratio of 1:30 with respect to metal. The progress of the formation of core–shell nanoparticles has been monitored using UV–visible spectroscopy and transmission electron microscopy. Detailed analysis of the nature of Au@Ag core–shell nanoparticles has been done with the help of HAADF-STEM technique, point-EDS analysis, elemental line scanning technique, and X-ray photoelectron spectroscopy. Variation of experimental conditions such as concentration of capping agent, molar ratio of Au and Ag, and temperature in the codigestive ripening process led to the realization that core–shell nanoparticles with thicker shell of silver can be obtained under certain reaction conditions. Alteration of the reaction conditions was also noted to affect the final Au@Ag nanoparticles with respect to average particle size and polydispersity. The as-prepared Au@Ag nanoparticles could be transformed to Au–Ag nanoalloys on being exposed to ultraviolet radiation of 254 nm. We have also attempted to elucidate the factors which dictate the formation of core–shell nanoparticles by comparing with the findings of theoretical studies from the literature with our experimental results.

A global market inventory is one of the largest and most significant resources of a manufacturing business. ABC analysis is one of the methods used extensively in manufacturing industries for inventory classification. The familiar ABC inventory classification approach categorizes inventory items as A, B and C classes according to their annual consumption value. To direct and control the inventory items more proficiently the inventories managers regularly classify and group all the inventory items. The objective of this paper is to create a periodic review policy based on the ABC classification in order to control the raw materials more efficiently. Based on the data collected through original equipment manufacturer, the necessary analysis was carried out. From the observed results, it was found that the developed periodic review policy improved the inventory turnover ratio from 3.15 to 2.13 by optimizing the inventory level for one year.

Gadolinium doped barium cerate (BCG) electrolytes Ce0.8Gd0.2O1.9+ xBaO (x = 0.1 and 0.4) were prepared by wet chemical method for the use in solid oxide fuel cells operating at intermediate temperatures (600 °C to 800 °C). The as-prepared powder sample was calcined at 900 °C. The calcination temperature was identified using differential scanning calorimetry (DSC) analysis. The orthorhombic perovskite phase formation was confirmed by XRD analysis. From TEM results, the particle size was found to be about 32 nm which is in a good agreement with XRD results. BCG nanoparticles were formed at lower sintering temperature due to using microwave furnace. By reducing the sintering temperature of solid electrolyte through microwave technique, the percentage of barium loss was successfully reduced and the prepared electrolyte can be a good choice for solid oxide fuel cells operating at intermediate temperatures.

Density, viscosity and speed of sound of three binary liquid systems: N-methylformamide (N-MFA) with carboxylic acids (ethanoic acid, propanoic acid and butanoic acid) have been determined at T = (303.15–318.15) K over the entire composition range. These experimental data have been used to calculate the excess volume (VE), excess isentropic compressibility (κsE), deviation in viscosity (Δη) and excess Gibbs free energy of activation of viscous flow (G∗E). The variations of these properties with composition of binary mixtures suggest loss of dipolar association, difference in size and shape of the component molecules, dipole–dipole interactions and hydrogen bonding between unlike molecules. The viscosity data have been correlated with Grunberg and Nissan, Katti and Chaudhri, and Hind et al. equations and the results are compared with the experimental results. The excess parameters have been fitted to the Redlich–Kister polynomial equation using multi parametric nonlinear regression analysis to derive the binary coefficients and to estimate the standard deviation.

Abstraction of chloride from a six-coordinate complex, trans-[Ir(H)(Cl)(iPr)4(POCOP)(PPh3)] (1) [(iPr)4(POCOP) = 2,6-bis(di-iso-propylphosphinito)benzene, κ3-C6H3-1,3-[OP(iPr)2]2], using NaBAr4fleads to the generation of a dinitrogen complex, trans-[Ir(H)(N2)(iPr)4(POCOP)(PPh3)][BAr4f] (6). Addition of H2to [Ir(H)(N2)(iPr)4(POCOP)(PPh3)]+(6) under extremely mild conditions (1 bar, 298 K) resulted in the reversible coordination of H2to generate the cis-[Ir(H)(η2-H2)(iPr)4(POCOP)(PPh3)]+(cis-11) complex. The cis-[Ir(H)(η2-H2)(iPr)4(POCOP)(PPh3)]+complex (cis-11) isomerized to a trans isomer, trans-[Ir(H)(η2-H2)(iPr)4(POCOP)(PPh3)]+(trans-11), at 253 K. The isomerization process has been studied and supported by computations. Employing an alternative route, protonation of the trans-[Ir(H)2(iPr)4(POCOP)(PPh3)] complex (2) at 183 K resulted in the formation of an identical, trans-[Ir(H)(η2-H2)(iPr)4(POCOP)(PPh3)]+complex (trans-11); upon warming the sample, the trans-H2/hydride complex isomerized to the cis isomer above 253 K. Two independent routes to obtain trans-[Ir(H)(η2-H2)(iPr)4(POCOP)(PPh3)]+(trans-11) species have been established. Reaction of trans-[Ir(H)(N2)(iPr)4(POCOP)(PPh3)][BAr4f] (6) with C2H4gave the cis-[Ir(H)(η2-C2H4)(iPr)4(POCOP)(PPh3)]+complex (cis-15), which also undergoes isomerization to yield an equilibrium mixture of cis/trans-[Ir(H)(η2-C2H4)(iPr)4(POCOP)(PPh3)]+complexes (cis-15and trans-15) at 253 K. The trans-[Ir(H)(N2)(iPr)4(POCOP)(PPh3)]+complex (6) is an excellent catalyst for hydrogenation of ethylene to ethane under very mild conditions.

Attempt has been made to characterize the hydrodynamic regime around the coastal waters of Goa for a pre-monsoon season, using MOHID, a two-dimensional finite volume model. The numerical model was forced with tides at open boundaries and calibrated using measured water levels and currents, during pre-monsoon season. The modeled water levels and currents were compared with field observations and found to be satisfactory, with correlation of 0.97 for water levels, 0.79 for zonal currents, and 0.84 for meridional currents. The ratio of diurnal (O1, K1) and semidiurnal (M2, S2) constituents was 0.63, suggesting that tides in this region are mixed, mainly semidiurnal in nature. The variation in amplitude of tidal constituents from the open boundary to the mouth and upstream of the Mandovi and Zuari estuaries has been modeled and compared with previous field studies and found to be satisfactory. The details of numerical scheme, methodology, and results are discussed in this paper.

Iron nanostructures with morphology ranging from discrete nanoparticles to nearly monodisperse hierarchical nanostructures have been successfully synthesized using solvated metal atom dispersion (SMAD) method. Such a morphological evolution was realized by tuning the molar ratio of ligand to metal. Surface energy minimization in confluence with strong magnetic interactions and ligand-based stabilization results in the formation of nanospheres of iron. The as-prepared amorphous iron nanostructures exhibit remarkably high coercivity in comparison to the discrete nanoparticles and bulk counterpart. Annealing the as-prepared amorphous Fe nanostructures under anaerobic conditions affords air-stable carbon-encapsulated Fe(0) and Fe3C nanostructures with retention of the morphology. The resulting nanostructures were thoroughly analyzed by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), and Raman spectroscopy. TGA brought out that Fe3C nanostructures are more robust toward oxidation than those of α-Fe. Finally, detailed magnetic studies were carried out by superconducting quantum interference device (SQUID) magnetometer and it was found that the magnetic properties remain conserved even upon exposure of the annealed samples to ambient conditions for months.

In coastal hydrodynamics, tides play a major role and it is important to understand the complexity of their characteristics along the difficult coastal areas like creeks, estuaries, bays and gulfs for any kind of engineering activities like harbor, jetty, dams and protection measures. In this study, six tidal constituents (K1, M2, N2, O1, P1 and S2) variations along the Gulf of Khambhat, west coast of India were studied with the spatially varied friction coefficient. A two-dimensional finite element-based numerical model (Telemac-2D) was developed and zones of different friction coefficients were identified by comparing numerically estimated levels and currents with that of measured and reported by earlier studies. Based on the comparisons, the gulf was divided into five zones of different bottom friction values. The numerical model was used to predict the tidal constituent's propagation along the gulf with the spatially varied bottom friction values and the amplitude and currents were analysed along the gulf. From the results, it was observed that the M2 (semi-diurnal) and K1 (diurnal) constituents influence the hydrodynamics of the gulf of Khmabhat significantly, compared to the other constituents. Further, a composite tide, inclusive of all six tidal constituents was applied to the offshore boundary of the numerical model and the tidal levels and currents were analysed along the gulf locations. It was observed that the combined effect of the constituents further increase the tidal amplitude up to 10m and the velocity up to 4ms-1. The validation of the numerical model showed good agreement.

Digestive ripening, a postsynthetic treatment of colloidal nanoparticles, is a versatile method to produce monodisperse nanoparticles and to prepare various bimetallic nanostructures. The mechanism of this process is largely unknown. Herein, we present a systematic study conducted using Au nanoparticles prepared by a solvated metal atom dispersion method to probe the mechanistic aspects of digestive ripening. In our study, experimental conditions such as concentration of capping agent, reaction time, and temperature, were found to influence the course of the digestive ripening process. Here it is shown that, during digestive ripening under reflux, nanoparticles within an optimum size window are conserved, and surface etching facilitated mass transfer resulted in monodisperse nanoparticles. Overall, digestive ripening can be considered as a kinetically controlled thermodynamic process.