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Due to the great fouling resistance property, (super)hydrophilic/underwater superoleophobic membranes are prevalent candidates for oil-polluted wastewater treatment. Even so, membrane fouling inevitably occurs during long-term operation. Therefore, it is of great significance to construct anti-fouling membranes with robust flux recovery. Herein, a polyvinyl pyrrolidone (PVP) coated porous potassium-doped g-C3N4 (PKCN) membrane was fabricated for the first time by vacuum filtration. The as-prepared membrane displays enhanced hydrophilicity and underwater superoleophobicity. The permeability of the membrane increased significantly after sonication treatment, which is attributed to the increased pore volume and small nanosheets size that shorten the transport pathway of water molecules. Importantly, owing to the high photo-Fenton activity, the PKCN membrane exhibits fast (within 15 min) and excellent flux recovery (96.5%) after the photo-Fenton cleaning process. Furthermore, after 10 repeated usages, the PKCN membrane still keeps stable permeability and excellent purification efficiency. This work opens a door for developing self-cleaning membranes with the superior anti-fouling ability for effective oil/water separation.

The CTS films were synthesized with automated, indigenous developed ultrasonic spray-pyrolysis (USP) by changing Sulphur concentration from 0.2 M to 0.35 M with the step of 0.5. The crystal structure, composition, surface analysis, UV characteristics of the CTS films are studied. Structural analysis confirms the formation of Cu2SnS3 tetragonal structure. Stoichiometric films are obtained with increase in S concentration. Films exhibited p type conductivity with energy band gap near to optimal value of 1.5 eV for thin film solar cell applications.

Membrane fouling is an ongoing challenge in the membrane filtration process. Herein, a photocatalytic membrane comprising a reactive layer was fabricated by engineering partially reduced graphene oxide/Ag nanoparticles/MIL-88A (prGO/Ag/M88A, pGAM) photocatalysts on the PVDF substrate membranes. Benefiting from the high conductivity of prGO and the surface plasmon resonance (SPR) effect of Ag nanoparticles (Ag NPs), the photo-sensitivity of the prGO/Ag/M88A is significantly enhanced. Compared to the membrane in the dark condition, the pGAM membrane displayed an enhanced dye removal efficiency (∼99.7%) and significantly improved permeability (∼189 L·m−2·h−1 bar−1) towards dye contaminants based on the synergistic filtration/photo-Fenton processes. Significantly, the membrane retained high perm-selectivity after 10 cyclic runs (183 L·m−2·h−1 bar−1 of permeability and 98.1% of dye removal), and its nano-channel structure did not collapse under high pressure (0.1–0.4 MPa). The membrane also exhibits antifouling properties with a high water flux recovery of more than 90%. In addition, the pGAM membrane exhibited a high MB degradation efficiency (∼90%) when it is directly used as a photocatalyst in the photo-Fenton system. The mechanism of the self-cleaning is also proposed through quenching experiments. The results of this study demonstrate that this self-cleaning membrane has huge promise for membrane anti-fouling and wastewater remediation.

Pearl River sediments have been reported to have changed greatly in composition due to the impact of human activities on erosion and landscapes in southern China since 2500 years BP. Here, sediments from four cores (PRD-1, PRD-3, PRD-6 and PRD-7) from the Pearl River Delta (PRD) were collected for high-density clay mineral analyses to determine the vertical variations in clay mineral compositions since the middle Holocene. The results showed that the clay mineral compositions of these four cores remained constant. In the PRD, the clay mineral assemblage dominantly consists of illite and kaolinite (averaging more than 85%), with smaller amounts of chlorite (averaging 10%) and scarce smectite (averaging 1%). The stable clay mineral assemblages in the PRD confirm that the clay mineral compositions of the sediments continuously supplied by the Pearl River have not changed. However, the smectite percentage in core PRD-7 increased by 7% downward from a depth of 12.4 m, which was correlated with the weathering of local volcanic materials and sediment transport in the east of the Pearl River under the influence of the Guangdong coastal current in winter. The stable clay mineral compositions in the core sediments indicate that the Pearl River sediments have accumulated naturally in the PRD instead of under the influence of human activities, which would have altered the compositions of the core sediments.

This paper reports disturbance in the mid-latitude sub-ionospheric VLF radio signals due to the super geomagnetic storm which began on 17 March 2015. Narrow-band signals from the NAA transmitter are studied for the storm period recorded at eight mid-latitude receiving stations spread over the Europe and USA. Daytime signals amplitude at all places showed a disturbing pattern after 17 March. Fluctuation in the nighttime signals significantly increased in the succeeding nights. As a primary effect of the storm, the entire diurnal signals in the transoceanic west to east long propagation paths enhanced by 3–5 dB, which gradually decreased over the period of ~ 10 days following the storm recovery. A different behavior was observed in the east to west short propagation paths over the landmass, where during the peak storm the daily variations of the VLF amplitude reduced to 20–25% of a normal day and, after ~ 10 days the signals returned to the pre-storm condition. Modeling of the radio waves in the west to east paths shows that the D-region electron density was increased by ~ 8-fold and varied up to 10 days. Electron density variations in the D-region closely follows the variations of precipitated electron flux as observed by the POES satellite over the region. The elevated electron density in the D-region ionosphere caused by the extension of the auroral precipitation to the mid-latitudes along with interference among the various waveguide modes in the earth-ionosphere waveguide during the storm is suggested for the cause of observed VLF signals behaviors.

The streamflow of Brahmaputra River Basin is vital for sustainable socioeconomic development of the Ganges delta. Frequent floods and droughts in the past decades indicate the susceptibility of the region to climate variability. Although there are multiple studies investigating the basin's future water availability, most of those are based on limited climate change scenarios despite the wide range of uncertainties in different climate model projections. This study aims to provide a better estimation of projected future streamflow for a combination of 18 climate change scenarios. We develop a hydrologic model of the basin and simulate the future water availability based on these climate change scenarios. Our results show that the simulated mean annual, mean seasonal and annual maximum streamflow of the basin is expected to increase in future. By the end of the 21st century, the projected increase in mean annual, mean dry season, mean wet season, and annual maximum streamflow is about 25, 178, 11, and 22%, respectively. We also demonstrate that this projected streamflow can be expressed as a multivariate linear regression of projected changes in temperature and precipitation in the basin and would be very useful for policy makers to make informed decision regarding climate change adaptation. HIGHLIGHTS Mean annual streamflow of the Brahmaputra River Basin (BRB) is expected to increase gradually over the 21st century.; Annual maximum streamflow is projected to increase by about 22% indicating a higher peak in the future flood events.; The projected mean annual, mean seasonal and annual maximum streamflow can be expressed as multivariate linear regression of projected changes in temperature and precipitation.

In the current paper we analyse the three classical tests of general relativity, namely, the precession of perihelion, deflection of light, and time delay in Einstein–æther gravity. Einstein–æther gravity has two static, spherically symmetric, charged black hole solutions corresponding to different constraints on its coupling constants c14 and c123. We investigate the aforementioned tests for both these solutions, graphically and analytically. We also tabulate our results and discuss the outcome, which is promising. We evaluate the results, when the coupling constants are varied over a vast range of values, both within the constraints set by the recent observational data, and also beyond, for a comparative study.

Biosorption is a convenient process for heavy metal remediation. In this study, banana peel was experimented to eliminate lead (Pb2+) from an aqueous solution following batch experiments. The functional groups of banana peel were identified by Fourier-transform infrared spectroscopy (FTIR). The adsorption mechanism was studied by the Langmuir and Freundlich adsorption isotherm model and determined the separation factor from the Langmuir adsorption isotherm. The adsorption of Pb2+ on dried banana peel had been studied at different adsorbent doses, pH, initial concentration of Pb, contact time, temperature, and agitation speed. After adsorption, Pb2+ was measured using atomic absorption spectroscopy (AAS). Maximum adsorption had taken place at pH 5 for adsorbent dose 45 g L-1. The optimum contact time and agitation speed was 30 minutes and 150 rpm, respectively for the initial Pb concentration of 100 ppm at 25°C. Both, Langmuir and Freundlich adsorption isotherm models shows the best fitting (r2 = 0.9978 and 0.9595) for Pb2+ adsorption. The maximum Pb2+ adsorption capacity was 2.1 mg g-1. The findings indicate that the banana peel waste could be a potential adsorbent for heavy metal removal. Moreover, the waste management problem could be solved in an eco-friendly manner by utilizing it for the eradication of Pb2+ from wastewater.

A one-pot direct synthesis of xanthine and uric acid derivates is reported. This simple yet efficient methodology illustrates concurrent formation of two C–N bonds using CuBr2 as catalyst and one of those C–N bonds is formed by uracil C6–H bond activation.

In 1990, Diamond [16] primarily established the base of fuzzy star–shaped sets, an extension of fuzzy sets and numerous of its properties. In this paper, we aim to generalize the convergence induced by an ideal defined on natural numbers ℕ , introduce new sequence spaces of fuzzy star–shaped numbers in ℝ n and examine various algebraic and topological properties of the new corresponding spaces as well. In support of our results, we provide several examples of these new resulting sequences.

Hydrogels were produced from mixtures of polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), and acrylic acid (AAc) using γ-radiation at doses of 3, 7, and 10 kGy and the effect of the variation in concentration of AAc within 0%–3% (w/v) on the gelation, swelling, crosslinking, thermal properties, crystallinity, mechanical properties, and surface morphology of the hydrogels were characterized and their adsorptive removal properties for methylene blue (MB) was investigated. The swelling trend was pH-dependent which was dictated by the dominance of two competing factors namely, crosslink density and hydrophilicity. Although thermal analysis showed that the presence of AAc decreased the thermal stability of the hydrogels, SEM images exhibited gradual morphological changes establishing the role of AAc as a crosslinker, and thus increasing the elastic moduli, toughness, and crystallinity of the hydrogels. However, correlation between the characterization results revealed that, in spite of AAc occupying some of the crosslinking sites within PVA–PVP networks, at low concentration (1% w/v), it could not polymerize enough to contribute to the crosslinks. FTIR spectral analysis revealed a possible gelation mechanism along with the points of interaction among the gel-components. MB adsorption capacity of the hydrogels reached a maximum of 117 mg/g following pseudo-second-order kinetics through film diffusion mechanism while the adsorption isotherm resembled most with that of Langmuir.

One of the interesting characteristics of topological defects is the deficit solid angle in the hypersurfaces t = constant. The area of a sphere of radius R in this space is not 4 π R 2 . In the work, we try to find the spacetime geometry of the outside of a spherically symmetric distribution of matter (within a galaxy that can be a galactic halo, etc) where the spacetime geometry is characterized by deficit solid angle in the hypersurfaces t = constant. We obtain a solution of Einstein’s field equations for the outside of spherically symmetric matter distribution in the galactic region. The solution describes a black hole. The several features of the solution are discussed.

Background Climate change and increasing demand in non-agricultural sectors profoundly affect the availability and quality of water resources for irrigated agriculture. The FAO AquaCrop simulation model provides a sound theoretical framework to investigate crop yield response to environmental stress. This model has successfully simulated crop growth and yield as influenced by varying soil moisture environments for crops. Integrating crop models that simulate the effects of water on crop yield with targeted experimentation can facilitate the development of irrigation strategies for high yield procurement and improving farm level water management and water use efficiency (WUE) under climatic condition of District Hyderabad, Sindh, Pakistan. Results This study was based on completely randomized block design with three treatments including T1 (30% soil moisture depletion), T2 (50% soil moisture depletion) and T3 (70% soil moisture depletion) with three replicates. In order to determine the crop water requirements under desired treatments, the gypsum blocks were used for computing the daily soil moisture depletion. The result shows that total volume of water applied to crop under T1, T2 and T3 was 9689, 5200 and 2045 m3 ha−1, respectively. As a result, the grain yield under T1, T2 and T3 was 13.2, 12.1 and 14.3 t ha−1, respectively. These results advocate that total yield of crop under T1 and T2 was less as compared to T3. The T3 gave higher yield and WUE compared than other treatments. On the other hand, results revealed that the simulated sunflower yields showed a good agreement with their measured under T3. The simulated grain yield was 15.5 t ha−1, while the measured yield varied from 12.1 to 14.3 t ha−1. This study suggested that WUE under T3 was more as compared to T1 and T2. The results showed that the T3 gave the highest crop yield in relation to WUE and optimize yield of sunflower crop under water scarcity. Conclusion The Aquacrop model could very well predict crop yield and WUE at T3 under experiential region for sunflower production.

The present paper highlights the importance of lac cultivation through Butea monosperma. We have modelled the suitable habitat of major lac host B. monosperma using MAXENT for the current and future climatic scenarios (RCPs 2.6, 4.5, 6.0 and 8.5). The study suggested the dominance of suitable habitats of B. monosperma in central-eastern to eastern and southern parts of the country. Temperature seasonality (Bio_4) was the most significant bioclimatic variable in regulating the distribution of B. monosperma followed by elevation and annual precipitation (Bio_13). The projection for the year 2050 suggested the habitat shift towards the eastern and southern parts. The study indicated the major habitat of B. monosperma continued to exist in the Chotanagpur plateau in eastern India. The model predicted approximately a 9–13% decrease in the overall potential habitat of B. monosperma by 2050, and the distribution of species would be nearly extinct from the northern and western parts. Presently, only the 5% lac host trees are being utilised for lac cultivation, and the study suggested that conservation and promotion of B. monosperma on projected suitable habitats and even by utilising 25% of resources, the lac production may jump manifold catering to global demand, rural economy and employment and shall contribute towards ‘Self Reliant India’.

Metabolic profiling of Pratylenchus thornei resistant and susceptible wheat genotypes indicates that fatty acid, glycerolipid and flavonoid classes of metabolites constitutively expressed in resistant wheat roots could reduce nematode reproduction. The root-lesion nematode Pratylenchus thornei reduces wheat production in many parts of the world. In this study the metabolic profiles of two wheat genotypes ‘QT16258’ (moderately resistant) and ‘Janz’ (susceptible) were compared at 8 weeks post inoculation with or without P. thornei. We performed untargeted liquid chromatography mass spectrometry analysis (LC–MS) of the wheat root samples. A total of 11,704 MS features were identified, out of which 765 MS features were annotated using in-house chemical standards. Principal components analysis (PCA) and partial least square discriminant analysis (PLS-DA) indicated dissimilarity of the metabolome between P. thornei resistant and susceptible genotypes. Two-way analysis of variance indicated that metabolic differences were mainly constitutive rather than induced by inoculation with P. thornei. Eighty-four annotated metabolites were significantly (p ≤ 0.01) higher in relative concentration in ‘QT16258’ than ‘Janz’ and belonged to the following classes of metabolites: flavonoids, fatty acids, glycerolipids, alkaloids, tannins, nucleotides, steroid glycosides and terpenoids. Eighty-five annotated metabolites were significantly (p ≤ 0.01) higher in relative concentration in ‘Janz’ than ‘QT16258’ and belonged to the following classes of metabolites: amino acids, sugars, flavonoids and alkaloids. Several metabolites at higher concentration in ‘QT16258’, including quercetin-3,4'-O-di-beta-glucoside (flavonoid), linoleic acid (fatty acid), lysophosphatidylethanolamine (glycerolipid), hirsutine (alkaloid), 1-methylsulfinylbutenyl-isothiocyanate (glucosinolate), could potentially strengthen the root cell walls to inhibit nematode penetration and/or reduce nematode motility. Some metabolites at higher concentrations in susceptible ‘Janz’, including phenolics, coniferyl alcohol and indole acetic acid conjugates, could be nematode attractants as well as part of a hypersensitive browning reaction to nematode invasion.

In this study, experimental investigations on the microhardness of the synthesized electroless Ni-P-TiO2 coated aluminium composite was carried out. The coated samples were characterized by scanning electron microscopy (SEM) for surface morphology and X-ray diffraction (XRD) pattern for phase recognition. The microhardness of the electroless Ni-P-TiO2 coated composite was measured and predicted by various machine learning algorithms. The recorded datasets were used for optimization by Response Surface Methodology (RSM) model whereas, training and testing of the four different Artificial Intelligence (AI) models were executed using machine learning methods. The four AI models applied in this study were Support Vector Machine (SVM), Artificial Neural Network (ANN), Random Forest (RF) and Extra Trees (ET). The objective of this analysis was to quantify the accuracy of microhardness prediction of four types of AI models along with RSM model. The obtained results revealed that the extra trees (ET) model showed outstanding performance amongst the five models for training, testing, and overall datasets with coefficient of correlation (R2), MSE and MAE value of 94.47, 75.38 and 4.67, respectively. This analysis therefore recommends the ET model in the prediction of microhardness of electroless Ni-P-TiO2 composite coating due to its superior and robust performance.

The physicochemical properties, swelling power, solubility, and digestibility of flour from four rice varieties (black, brown, white, and waxy rice flour) were analyzed. The results showed that the black and brown rice had high‐amylose percentage (21.8% and 20.5%), a relatively low percentage of starch content (68.1% and 79.1%), and lower swelling power (6.6% and 7.6%) and solubility (13.5% and 15.7%), respectively. Waxy rice flour attributed to lower gelatinization temperatures and higher enthalpy values. Meanwhile, the brown, black, and white rice showed higher gelatinization temperature and lower enthalpy value. The black and brown rice flour exhibited lower pasting and viscosity values as compared to waxy rice flour. The results showed that all rice flour had an A‐type X‐ray diffraction pattern, and after cooking all rice flour showed V‐type polymorphs except waxy rice flour. Brown and black rice flour after cooking have lower digestion rate than white rice and waxy rice flour, probably due to its lower expansion and solubility rates, and higher gelatinization temperature., Rosa Roxburghii seed oil was of high quality in terms of its high amount of unsaturated fatty acids. Heat treatment of R. roxburghii seed oil showed an increase in the relative percentage of linoleic acid and linolenic acid isomers with increasing temperature and time. The formation of linoleic acid and linolenic acid isomers followed a zero order reaction.

We present results from \textit{Chandra} X-ray observations and 325 MHz Giant Metrewave Radio Telescope (GMRT) observations of the massive and X-ray luminous cluster of galaxies Abell S1063. We report the detection of large-scale \lq\lq excess brightness\rq\rq\ in the residual \textit{Chandra} X-ray surface brightness map, which extends at least 2.7 Mpc towards the north-east from the center of the cluster. We also present a high fidelity X-ray flux and temperature map using \textit{Chandra} archival data of 122 ksec, which shows the disturbed morphology in the cluster. The residual flux map shows the first observational confirmation of the merging axis proposed by earlier simulation by \citet{Gomez2012AJ....144...79G}. The average temperature within $R_{500}$ is $11.7 \pm 0.56$ keV, which makes AS1063 one of the hottest clusters in the nearby Universe. The integrated radio flux density at 325 MHz is found to be $62.0\pm6.3$ mJy. The integrated spectrum of the radio halo follows a power-law with a spectral index $\alpha=-1.43\pm 0.13$. The radio halo is found to be significantly under-luminous, which favored for both the hadronic as well as the turbulent re-acceleration mechanism for its origin., Comment: Accepted for publication in MNRAS (12 pages, 8 figures, 2 tables)

Pathology image analysis is an essential procedure for clinical diagnosis of numerous diseases. To boost the accuracy and objectivity of the diagnosis, nowadays, an increasing number of intelligent systems are proposed. Among these methods, random field models play an indispensable role in improving the investigation performance. In this review, we present a comprehensive overview of pathology image analysis based on the Markov Random Fields (MRFs) and Conditional Random Fields (CRFs), which are two popular random field models. First of all, we introduce the framework of two random field models along with pathology images. Secondly, we summarize their analytical operation principle and optimization methods. Then, a thorough review of the recent articles based on MRFs and CRFs in the field of pathology is presented. Finally, we investigate the most commonly used methodologies from the related works and discuss the method migration in computer vision.

Cloud data migration is the process of moving data, localhost applications, services, and data to the distributed cloud processing framework. The success of this data migration measure is relying upon a few viewpoints like planning and impact analysis of existing enterprise systems. Quite possibly the most widely recognized process is moving locally stored data in a public cloud computing environment. Cloud migration comes along with both challenges and advantages, so there are different academic research and technical applications on data migration to the cloud that will be discussed throughout this paper. By breaking down the research achievement and application status, we divide the existing migration techniques into three strategies as indicated by the cloud service models essentially. Various processes should be considered for different migration techniques, and various tasks will be included accordingly. The similarities and differences between the migration strategies are examined, and the challenges and future work about data migration to the cloud are proposed. This paper, through a research survey, recognizes the key benefits and challenges of migrating data into the cloud. There are different cloud migration procedures and models recommended to assess the presentation, identifying security requirements, choosing a cloud provider, calculating the expense, and making any essential organizational changes. The results of this research paper can give a roadmap for data migration and can help decision-makers towards a secure and productive migration to a cloud computing environment.

The comprehensive study of the reactions of carbonyl compounds and ethyl diazoacetate in the presence of a Brønsted acid catalyst is described. In result, a broad range of 3-oxo-esters were synthesized from a variety of ketones and aliphatic aldehydes by 1,2-aryl/alkyl/hydride shift. Aryl-methyl ketones produced only aryl-migrated products, whereas other ketones yielded a mixture of products. For diaryl ketones, the identity of two inseparable migrated products was confirmed by two-dimensional NMR spectroscopy.

Owing to their good flexibility, biocompatibility, and capability to convert mechanical energy to electrical energy, electrospun poly(vinylidene fluoride) nanofibers (PVDFNFs) have attracted considerable attention for energy harvesting as well as wearable and self-powered electronics. However, inadequate mechanical strength and low piezoelectric output are major concerns for their practical application. Herein, we report an effective method for fabricating mechanically robust PVDFNFs with enhanced piezoresponse by incorporating phenyl-isocyanate functionalized graphene oxide (IGO) as an efficient nanofiller. The presence of IGO endowed PVDFNFs with a rough surface morphology, enhanced crystallinity, and electroactive β phase. Excitingly, enhancements of 303% and 332% in the ultimate tensile strength and modulus, respectively, were achieved for the IGO-incorporated PVDFNFs. Furthermore, the acoustic sensitivity of the composites was 63.09% higher than that of the pristine PVDFNFs. The composites had a minimum sensing force of 0.012 N, which was 20% less than the minimum sensing force of the pristine PVDFNFs. The incorporation of IGO enhanced the power generation capability of the composites by 55.23% compared with that of the pristine PVDFNFs. Thus, the as-prepared composites hold great promise for the fabrication of mechanically robust, high-performance piezoelectric composites for mechanical energy conversion applications.

We show that the approximate quasi-orthogonality of two operator algebras is equivalent to the algebras being approximately private relative to their conditional expectation quantum channels . Our analysis is based on a characterization of the measure of orthogonality in terms of Choi matrices and Kraus operators for completely positive maps. We present examples drawn from different areas of quantum information .

This research assesses the current situation of drinking water and sanitation at Shahidbug slum in Dhaka, Bangladesh, in comparison with targets 6.1 and 6.2 of Sustainable Development Goal (SDG) 6....

To curtail flammability risks and improve material properties, flame retardants (FRs) and fillers are mixed into rubbers. High loadings of aluminum trihydroxide (ATH) and carbon black (CB) are the most used FRs and reinforcing additive, respectively, in rubbers. To reduce loading without losing mechanical properties, partial substitution of ATH as well as CB by low amounts of multilayer graphene (MLG) nanoparticles is investigated. The high aspect ratio MLG is made of ten graphene sheets. In polybutadiene/chloroprene (BR/CR) nanocomposites 3 phr MLG replaced 15 phr CB and/or 3 phr ATH. Material and mechanical properties as well as fire behavior of the nanocomposites are compared to BR/CR with 20 phr CB both with and without 50 phr ATH. MLG appears as a promising nanofiller to improve the functional properties: replacement of CB improved rheological, curing, and mechanical properties; substitution of ATH improved nanocomposite properties without affecting flame retardancy.

Modulated electron conductivity (EC), p-n junction behavior and light-harvesting semiconductivity in reduced graphene oxide (rGO) is observed. Pristine graphene oxide (GO) film on borosilicate glass was reduced by ascorbic acid (AA), Glucose (GC), hydrogen iodide (HI), thiourea (TU), hydrazine solution (HS) and hydrazine vapor (HV) to obtain respective rGOAA, rGOGC, rGOHI, rGOTU, rGOHS and rGOHV films. The morphologies of the films were studied by SEM image and PXRD spectra. The functional groups were studied by IR, Raman and XPS spectra. Except rGOHV, the samples exhibited tunable electron conduction behavior (EC) following the trend as rGOHS (1.1 × 10−1 mA/V) > rGOTU (4.4 × 10−3 mA/V) > rGOGC (1.5 × 10−3 mA/V) > rGOHI (8.9 × 10−4 mA/V) > rGOAA (2.6 × 10−4 mA/V). However, rGOHV exhibited p-n junction behavior with the knee point at 0.66 and -0.62 V for the forward and reverse bias, respectively. rGOHS and rGOHV could exhibit photocatalytic activity due to the presence of doped N. The water-splitting efficiency of rGOHS and rGOHV are 2.38 and 3.75 μmol/hg, respectively, whereas respective dye degradation efficiencies are 84.16 and 92.48%. TGA data confirms that rGOHV sustains with some water adsorbing capacity that can aid the hydrodynamics. Further, the hydrodynamics within rGO film was confirmed from hydronium ion conductivity.

Freestanding carbon nanofibers loaded with bimetallic hollow nanocage structures were synthesized. The nanocages inherited the rhombic dodecahedral morphology of the zeolitic imidazolate framework (ZIF) precursors, ZIF-8 and ZIF-67. As anode materials for lithium-ion batteries (LIBs), the bimetallic nanocage-loaded freestanding carbon nanofibers effectively buffered volume expansions and alleviated pulverization through their different reduction and oxidation potentials. The higher capacities of the composite anodes arose via the formation of the LixZn alloy and Li2O by Zn and Co ions, respectively, and the enhanced conductivity conferred by the carbon nanofibers. A synergistic effect of the composite components toward the strong electrochemical performance (688 mA h·g−1 at 1200 mA·g−1) of the bimetallic nanocage-loaded fibers was demonstrated through the superior long-term stability of the anode (1048 mA h·g−1 after 300 cycles at 100 mA·g−1), suggesting that the fabricated anode can be a promising material for use in portable LIBs.

The chemical inertness of polyethylene makes chemical recycling challenging and motivates the development of new catalytic innovations to mitigate polymer waste. Current chemical recycling methods yield a complex mixture of liquid products, which is challenging to utilize in subsequent processes. Here, we present an oxidative depolymerization step utilizing diluted nitric acid to convert polyethylene into organic acids (40% organic acid yield), which can be coupled to a photo- or electrocatalytic decarboxylation reaction to produce hydrocarbons (individual hydrocarbon yields of 3 and 20%, respectively) with H2 and CO2 as gaseous byproducts. The integrated tandem process allows for the direct conversion of polyethylene into gaseous hydrocarbon products with an overall hydrocarbon yield of 1.0% for the oxidative/photocatalytic route and 7.6% for the oxidative/electrolytic route. The product selectivity is tunable with photocatalysis using TiO2 or carbon nitride, yielding alkanes (ethane and propane), whereas electrocatalysis on carbon electrodes produces alkenes (ethylene and propylene). This two-step recycling process of plastics can use sunlight or renewable electricity to convert polyethylene into valuable, easily separable, gaseous platform chemicals.

The high temperature phase of SrPd2Sb2 polymorphs exhibits bulk superconductivity below 0.6 K. The electron phonon coupling constant and density of states are two major factors that control the superconductivity in this intermetallic compound. Here we report the detailed physical properties including structural, elastic, electronic, and optical properties of this superconducting phase by using DFT-based computational method. The calculated lattice parameters and density of states show good agreement with the experimental data. This intermetallic is ductile and comparatively soft with respect to other members of this family. This compound exhibits metallic conductivity mostly emerging from Pd and Sb atoms that is different from other similar type of superconducting materials. The strong covalent interactions in Sb-Sb and Sb-Pd bonds define the electronic characteristics of this superconducting material. The optical properties of this superconductor are fairly comparable with other similar compounds in this family.

This work is based on the effect of different gamma doses with pre- and post-alpha-irradiated PM-355 polymer (polycarbonate of allyl diglycol). The phase crystallinity and structural analysis of the reference and irradiated PM-355 polymer were analyzed using an X-ray diffraction (XRD) study. It is revealed that the irradiation and etching reduce the %crystallinity but increase the crystallite size of the PM-355 polymer. The increase in crystallite size of PM-355 polymer after irradiation is supported by the scanning electron microscopic (SEM) analysis. The etching of the samples results in an increase in its track diameter. The optical band gap energy, measured by ultraviolet-visible (UV-VIS) spectroscopy, shows a decrement trend with the increase of gamma and alpha irradiation doses, and etching for all sets of samples under investigation. The number of carbon atoms per conjugation and per cluster has increased after gamma irradiation and etching. However, the increment is more pronounced for etched samples compared to nonetched ones. This indicates that etching results in a bigger size of cluster. Photoluminescence (PL) for both cases before and after etching has a dominant peak around 430 nm before and after irradiation, and change in peak intensity after irradiation confirmed that particle bombardment induced defects and clusters in the PM-355, which serves as nonradiative centers. The polymer can be used as a detector for gamma irradiation.

In this paper, we are proposing a three-layered hybrid compact star model with a distinct equation of states (EOSs) in the realm of general relativity. The core is assumed to be quark matter described by the MIT-bag model, an intermediate layer filled with neutron liquid and a thin envelope of matter satisfying a quadratic EoS. Three pairs of interfaces are matched by using Darmois–Israel conditions. For better and easier tuning, we have chosen $$\alpha $$ as a free parameter for core, k for intermediate layer and g and t for envelope, while the rest of the constant parameters are linked with mass and radius. Most of the physical parameters such as density, pressures and EoS parameters are continuous in all the three regions; however, $$v_t^2$$ and stability factor are discontinuous. This is because of the non-differentiability of $$p_t$$ ’s at the interfaces. Hence, stability is not defined at the interfaces. Further, matching of $$p_t$$ ’s can be performed by tuning suitable values of the free parameters $$\alpha , ~k, ~g$$ and t. Further, the most prevailing aspect of this method is that we can arbitrarily choose the radii of each region. As per Buchler and Barkat (PRL 27: 48, 1971) and Baym et al.(PRL 175: 225, 1971) , there exists a smooth transition density between quark core and intermediate neutron-liquid layer at about $$\rho > 10^{14}~{\mathrm{g/cc}}$$ . Our calculation shows that the smooth transition density is at about $$\rho _I=4.16 \times 10^{14}~ {\mathrm{g/cc}}$$ which is in good agreement with the above prediction.

In this work, polycrystalline Ni0.25Cu0.13Zn0.62Fe2−xO4−3x/2 ferrites were synthesized via the solid-state reaction route and sintered at four different temperatures (1100–1250 °C; in steps of 50 °C) to investigate the impacts of iron-deficiency amount on the structural, micromorphology, elastic, and electromagnetic properties. The crystal structure, phase formation, micromorphology, and grain size were examined through X-ray diffraction, Fourier transforms infrared spectroscopy and scanning electron microscopy. The structural analysis confirms the evolution of the cubic spinel skeleton without any impurity phase. The lattice parameter increases linearly with iron-deficiency amount at 1100 °C, while it varies non-linearly at 1150, 1200, and 1250 °C. The elastic properties such as stiffness constants, elastic constants, longitudinal wave velocity, transverse wave velocity, mean elastic wave velocity, Poisson’s ratio, and Debye temperature were calculated from infrared spectroscopic data. The elastic moduli were corrected via Hassselman and Fulrath, Ledbetter and Datta, and the elastic theory models. The microstructural analysis reveals that agglomerated and abnormal grain growth and agglomerations take place due to the magnetic interaction between the individual grains. An improvement in dielectric properties with sintering temperature is evident due to the improved densification and generation of Fe2+ ions. The AC conductivity analysis suggests that the electrical conduction process is attributed to the small polaron hopping. Nyquist representation proclaims that the electrical conduction is ascribed to the contribution of the grain boundary. The observed variations in permeability and magnetic loss with iron-deficiency amount may be accredited to the modification of density, porosity, grain size, and anisotropy contribution.

We have designed and developed a compact, contactless, chipless, high frequency wireless passive LC pressure sensor tag capable of measuring pressure from 0 Pa to 60 kPa. The LC pressure sensor tag design consists of a parallel combination of a planar inductor and a pressure sensitive interdigitated capacitor (IDC). The readout or signal detection and signal processing system combines a Colpitts oscillator, different electronic circuits, and a microcontroller-based signal processing unit. Operation of the sensor is based on mutual coupling of the inductor of the LC pressure sensor tag and the oscillation coil of the Colpitts oscillator. The pressure sensitive IDC consists of interdigitated electrodes and a melamine foam containing poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) as an elastic pressure sensitive dielectric material. When pressure is applied to the LC pressure sensor tag, the capacitance of the IDC sensing element changes, which changes the resonance frequency. Because the LC pressure tag and the inductor of the oscillator are inductively coupled, the frequency of oscillation of the Colpitts oscillator changes. The LC pressure sensor has a highly sensitive sensing response of 762.65 Hz/kPa and a linear sensing performance over a wide measurement range, with a correlation coefficient ( $\text{R}^{\sf 2}$ ) of 0.997. The LC pressure sensor tag is lightweight, highly sensitive, inexpensive to fabricate, and has good repeatability and stability values in the percentage of 2.8 and 1.1, respectively.

Many previous studies that evaluated the impact of adaptation to climate change on poverty failed to assess how the gains from adaptation can be assessed from the multidimensional poverty perspecti...

This study utilizes recall data from smallholder farmers in selected provinces in Zambia to examine the role of social and institutional networks, as well as other farm and household factors in the adoption and diffusion of conservation agriculture (CA) technology. We employed a dynamic discrete-time hazard model to capture the time path to adoption. The empirical results show that conditional on several potentially confounding factors, conservation agriculture technology adoption and diffusion are positively and significantly influenced by farmers’ access to information from social networks and institutional networks like extension services. Adoption decisions are also found to be significantly influenced by age, education, market distance, as well as location fixed effects.

The effect of three different interlayer stacking arrangements of bilayer (BL) molybdenum disulfide (MoS2) channel material on the device behavior of p- and n-metal–oxide–semiconductor field-effect transistors (MOSFETs) is extensively investigated using first-principles calculation based on density functional theory, emphasizing electronic properties such as the eigenstates, effective mass, band structure, and total energy of the BL-MoS2 for various stacking arrangements. The corresponding effects on the MOSFET device characteristics are then analyzed. The results indicate that the hole effective masses in both the longitudinal (transport) and transverse direction are highly sensitive to the interlayer stacking arrangement, and the performance of the p-MOSFET can be significantly tuned for a suitable stacking configuration of the BL-MoS2. Indeed, 24.12% and 31.37% improvements in the on-state current and transconductance are observed, respectively, for the p-MOSFET compared with the natural stacking arrangement of BL-MoS2. The ballistic BL-MoS2-based p- and n-MOSFETs with the tuned stacking arrangement demonstrate an on-state current on the order of 103 µA/µm along with an on-state/off-state current ratio greater than 103, a near-ideal (> 65 mV/decade) subthreshold swing, and small (

We propose a highly sensitive hollow core photonic crystal fiber (HCPCF) for liquid sensing in the terahertz (THz) region. Asymmetrical rectangular shaped air holes in the cladding region along with Topas glass as a background material is used to get high sensitivity and low confinement loss. The full vector finite element method (FEM) is used to calculate relative sensitivity and other parameters of the proposed liquid sensor where frequency range is taken from 1 THz to 2 THz. The strut distance variations are also studied in this study to find out minimum strut length to make the proposed sensor fabrication friendly. Numerical analysis shows the maximum relative sensitivity of 91.42% for water, 92.55% for acetic acid and 94.03% for chloroform at optimal conditions along with the minimum confinement loss of 1.06 × 10−9cm−1 for water, 2.02 × 10−10cm−1 for acetic acid and 1.39 × 10−11cm−1 for chloroform. To the best of our knowledge, the proposed HCPCF sensor shows maximum relative sensitivity for liquid.

In understanding the catalytic efficacy of silver (Ag0) and gold (Au0) nanoparticles (NPs) on glass-ceramic (GC) crystallization, the microstructure–machinability correlation of a SiO2–MgO–Al2O3–B2O3–K2O–MgF2 system is studied. The thermal parameters viz., glass transition temperature (Tg) and crystallization temperature (Tc) were extensively changed by varying NPs (in situ or ex situ). Tc was found to be increased (Tc = 870–875 °C) by 90–110 °C when ex situ NPs were present in the glass system. Under controlled heat-treatment at 950 ± 10 °C, the glasses were converted into glass-ceramics with the predominant presence of crystalline phase (XRD) fluorophlogopite mica, [KMg3(AlSi3O10)F2]. Along with the secondary phase enstatite (MgSiO3), the presence of Ag and Au particles (FCC system) were identified by XRD. A microstructure containing spherical crystallite precipitates (∼50–400 nm) has been observed through FESEM in in situ doped GCs. An ex situ Ag doped GC matrix composed of rock-like and plate-like crystallites mostly of size 1–3 μm ensured its superior machinability. Vicker's and Knoop microhardness of in situ doped GCs were estimated within the range 4.45–4.61 GPa which is reduced to 4.21–4.34 GPa in the ex situ Ag system. Machinability of GCs was found to be in the order, ex situ Ag > ex situ Au ∼ in situ Ag > in situ Au. Thus, the ex situ Ag/Au doped SiO2–MgO–Al2O3–B2O3–K2O–MgF2 GC has potential for use as a machinable glass-ceramic.

Membrane distillation (MD) has attracted significant attention owing to its unique advantages in desalination of hypersaline water. However, commercially available membranes used for MD desalination face fouling and wetting issues in treating wastewater containing low surface tension contaminants (e.g., oil and alcohol) and surface-active agents (e.g., surfactants). Herein, a superamphiphobic (i.e., superhydrophobic and near-superoleophobic) MD membrane was fabricated using the electrospinning technique followed by a simple surface modification step for treating challenging wastewater containing low surface tension substances. In order to fabricate a superamphiphobic membrane, a highly hydrophobic nanofibrous mat was first prepared by electrospinning a mixture of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP, also refers to PH) and reduced graphene oxide (rGO). Surface superamphiphobicity was then supplemented by a facile one-step grafting of low surface energy fluoroalkylsilane POTS. The influence of this one-step surface modification on the morphology and physicochemical properties of the membranes was investigated, revealing the altered elemental composition and enhanced hydrophobicity of the electrospun nanofiber mats. The resulting membranes demonstrated superamphiphobicity, confirmed by their wetting resistance evaluated with water and low surface tension liquids. The anti-wetting performance of the membrane was tested through desalinating 35 g L−1 sodium chloride solution in the presence of a surfactant (sodium dodecyl sulfate, SDS) in the direct contact membrane distillation (DCMD) unit. Membranes modified with fluoroalkylsilane (PH–rGO–POTS) exhibited enhanced stability and durability in terms of both permeation flux (∼27.94 kg m−2 h−1) and salt rejection (∼100%), while control membranes suffered from severe wetting problems.

This investigation focuses on a simulation-based power-loss optimization scheme, which is applied to laboratory developed general-purpose inverter-stack circuit, fabricated using high-voltage SiC-MOSFET. The optimization mainly addresses the external elements under fixed output current. It is found, that an increase in switching frequency causes increased loss, which is however less than that calculated by following the conventionally predicted linear dependence on the frequency. The switching loss is also strongly varying, in accordance with the output current variation, which is determined by the circuit requirements. Here, it is demonstrated, that circuit simulation with an accurate compact model can be successfully applied to realize significant improvements, leading to lower power loss under the requested operating condition. It is also found that the SiC-MOSFET can maintain the efficiency of nearly 98% even for high-frequency operations.

Catalytic pathways to produce high carbon number compounds from benzyl phenyl ether require multiple steps to break the aryl etheric carbon–oxygen bonds; these steps are followed by energy-intensive processes to remove oxygen atoms and/or carbon–carbon coupling. Here, we show an upgrading strategy to transform benzyl phenyl ether into large phenolic (C12–C22) compounds by a one-step C–O breaking and C–C coupling catalyzed by metal triflates under a mild condition (100 °C and 1 bar). Hafnium triflate was the most selective for the desired products. In addition, we measured the effect of solvent polarity on the catalytic performance. Solvents with a polarity index of less than 3.4 promoted the catalytic activity and selectivity to C12–C22 phenolic products. These C12–C22 phenolic compounds have potential applications for phenol–formaldehyde polymers, diesel/jet fuels, and liquid organic hydrogen carriers.

Cu2SnS3(CTS) films are prepared on soda lime glass substrates by ultrasonic spray pyrolysis at different Sn concentration. The structural, composition, morphological and optical properties of the CTS films are discussed. Structural analysis confirms the formation of Cu2SnS3tetragonal structure. Stoichiometric films are obtained with increase in Sn concentration. Films exhibited p type conductivity with energy band gap close to optimum value of 1.5 eV for thin film solar cell applications. © 2020 Elsevier Ltd. All rights reserved.

Polyurethanes (PU) are versatile polymers which can be molded to any shape. Reinforcing suitable micro and nano particles in the PU foam enhances its comfort, warmth and convenience to the consumer products. PU foams have versatile application due to its commendable comfort and insulation properties. Challenge for the foam is its strength, in the present work strength of PU foam is increased by reinforcing alumina to it. For the weight fraction of 1–35% of alumina, maximum increase in tensile strength and modulus of 35% was obtained. X-ray diffraction, SEM analysis and sol fraction of the composites were also carried out.

We consider the gauged model of Siegel type chiral boson with a Lorentz non-covariant mass-like term for the gauge fields which is found to be equivalent to a model of boson where the kinetic term is like the kinetic term of Floreanini-Jackiw type chiral boson. We carry out the quantization of gauge non-invariant version this model in both the Lagrangian and Hamiltonian formulation. The quantization of the gauge-invariant version of this model in the extended phase space also has been carried out in the Lagrangian formulation. The gauge-invariant version of this model in the extended phase space is found to map onto the physical phase space with the appropriate gauge fixing condition. BRST symmetry associated with this model has been studied with different gauge fixing terms. It has been shown that the same model shows off-shell as well as on-shell BRST invariance depending on the choice of gauge fixing term.

Land degradation is human-induced and natural process that adversely affects the land, to function effectively within a complex ecosystem. In recent years, the Kallar watershed has encountered various kinds of multifarious problems on both land and water in the urban and its environs. The upper part of the study area is facing water scarcity problems in the past few years, but which included no such rare occurrences in the past. The mid-portion in the vicinity of foothills are highly affected by soil erosion, whereas the lower portion of the area has faced problems like land degradation, such as an unusual increase of wastelands and conversion of good agriculture lands into construction plots. Apart from these, the study area is frequently affected by nature induced disasters like a landslide, forest fire, flooding, and drought. In this complex situation, the qualitative assessment of human-induced land degradation and its impact is essential. For this, Geospatialbased Multi-Criteria Evaluation (MCE) as a multidisciplinary approach has been adopted. To assess land degradation, six major criterions are preferred such as terrain (slope, elevation), environment (landuse/land cover, NDVI), soil erosion, and demography (population density). Considerable weights and ranks were assigned through an empirical MCE method. Based on the criteria, the land degradation was carefully delineated into five significant categories such as low (38.3%), moderately (23.6%), marginally (15.4%), highly (4.8%), and severely degraded (17.8%). The depletion of vegetation cover on hilly terrain and subsequent cultivation without proper protection measures constitute the possible reason for severe soil erosion and land degradation.

In this study, polycrystalline (1 − y) [0.996Na0.475K0.475Li0.05Sb0.05Nb0.95O3–0.004Bi0.95Nd0.05FeO3] (NKLNSO–BNFO) + (y) [Co0.50Cu0.15Zn0.35Fe1.95Mn0.05O4] (CCZMFO) (where y = 0.0–1.0) composites were prepared via the solid-state sintering route at 1273 K and 1323 K. The XRD and FTIR analyses asserted that the individual phases belong to the orthorhombic and cubic spinel structure, respectively, and additionally confirm the coexistence of the individual phases. The dielectric constant was decreased while the dielectric loss increased with increasing CCZMFO content. The grain size was decreased with increasing CCZMFO content due to the pinning effect. The $$\left( {\varepsilon^{\prime}_{\max } \left( \omega \right) - \varepsilon^{\prime}_{\min } \left( \omega \right)} \right)/\varepsilon^{\prime}_{\max } \left( \omega \right) $$ ratio was increased with increasing CCZMFO content and tanδ exhibits suitable value at x = 0.4 and x = 0.3 at 1273 K and 1323 K. The complex impedance and electric modulus studies revealed a significant benefaction from the grain boundary contribution to the electrical conduction and exhibited non-Debye relaxation. The AC conductivity study asserted that the small polaron hopping is ascribed to electrical conduction. The permeability exhibits almost frequency-independent characteristics. A maximum magnetoelectric voltage coupling coefficient of ~ 1.35 V cm−1 Oe−1 was observed with 80% CCZMFO at 1323 K.

A manufacturing process hand layup technique was used to produce carbon fiber/epoxy laminates with the epoxy matrix with a variation of 0.5 wt % to 2 wt% carbon nanotubes (CNTs). Microstructural ob...

Using a pulsed laser ablation system, core–shell Au@Se nanoparticles (Au@Se NPs) were efficiently synthesized and incorporated into a polymeric nanofibrous cellulose acetate (CA)/polyvinylidene fluoride (PVDF) solution prior to electrospinning. Highly crystalline Au@Se NPs were formed in a spherical core/shell configuration with core and shell diameters of 10.5 nm and 25 nm, respectively. The networked scaffolds were decorated with micro-distensions with lengths ranging from 2.8 to 4.3 μm at the lowest Au@Se NPs content. Cell viability analysis confirmed the high biocompatibility of the produced scaffolds, with survival ratios around 91.1 ± 3.4% and 88.2 ± 4.3% at the lowest and highest concentrations of Au@Se NPs, respectively. Obviously, the cells spread and proliferated significantly through the nanofibers. Moreover, the cells not only grew on the surface, but also connected through the deeply porous interior of the nanoparticles. The compositions of these nanofibrous scaffolds can be manipulated to realize a new design for the dressing and healing of wounded tissues.

In this work, analytical solution of hybrid Maxwell nanofluid of the vertical channel due to pressure gradient is discussed. By introducing dimensionless variables the governing equations with all levied initial and boundary conditions is converted into dimensionless form. Fractional model for Maxwell fluid is developed by Caputo time fractional differential operator by using the constitutive relation. The dimensionless expression for temperature and velocity are found using Laplace transform. Draw graphs of temperature and velocity by Mathcad software and discuss the behavior of flow parameters and the effect of fractional parameters. As a result, we have found by increasing the volumetric fraction of copper and alumina temperature increases and velocity decreases. Also, fluid flow properties showed dual behavior for small and large time, respectively, by increasing fractional parameters values.