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Besides developing a large number of catalysts for hydrogen evolution reaction (HER) in alkaline electrolytes, its conversion efficiency remained low. Herein, we have developed mixed-dimensional heterostructures of niobium disulfide (NbS2) with graphene foam grown on nickel foam (NbS2-Gr-NF). The strong lateral fusion results in activating the catalytic sites of NbS2, the three-dimensional substrate provides easy access of electrolyte to active sites and increased electrochemically active surface area, while enhanced conductivity provides faster transfer of electrons to and from active sites. Therefore, NbS2-Gr-NF heterostructures resulted in an exceptionally high current density of 500 mA cm−2 at a very low overpotential of 306 mV in 1 M KOH solution and even can achieve the current density values of 914 mAcm−2 at 338 mV only at a slight increase in overpotential (32 mV). Moreover, a Tafel value of ~72 mV dec−1 confirms that as-developed heterostructure provides fast reaction kinetics where the reaction is mainly controlled by the Volmer step. Achieving such high current density at a faster rate with high stability makes NbS2-Gr-NF heterostructures a potential candidate for water-splitting, especially in alkaline electrolytes.

Lithium-sulfur battery is desirable for the future potential electrochemical energy storage device with advantages of high theoretical energy density, low cost and environmental friendliness. However, some natural hindrances, particularly fast capacity degradation resulting from the migration of dissolved polysulfide intermediates, remain to be significant challenges prior to the practical applications. In this work, a composite interlayer of carbon nanofibers (CNFs) which are enriched by Co-based metal organic frameworks (ZIF-67) growth in-situ is exploited. Notably, physical blocking and chemical trapping abilities are obtained synergistically from the ZIF/CNFs interlayer, which enables to restrain the dissolution of polysulfides and alleviate shuttle effect. Moreover, the three-dimensional fiber networks provide an interconnected conductive framework between each ZIF microreactor to promote fast electron transfer during cycling, thus contributing to excellent rate and cycling performance. As a result, Li-S cells with ZIF/CNFs interlayer show a high specific capacity of 1334 mAh g−1 at 1 C with an excellent cycling stability over 300 cycles. Besides, this scalable and affordable electrospinning fabrication method provides a promising approach for the design of MOFs-derived carbon materials for high performance Li-S batteries.

E-commerce allows businesses to reach millions of potential consumers and suppliers on online. It decreases the need for personnel and creates flexibility and convenience for the organization to develop relationships with potential buyers and sellers. It provides the consumer with a more personalized experience, eliminating the need for physical presence and with the aid of home delivery-commerce has been a part of the shopping experience globally. However, the recent few years have also seen an increasing trend in e-commerce in SMEs, even at a national level. In this study, we investigated the link between EC and business strategy and how it affects the management approach.

Hydrogen production from water splitting is highly desired for the green and clean energy device but remains a great challenge. In this regard, cobalt-phthalocyanine (PyCoPc) and composite of PyCoPc with graphene oxide (GO) were fabricated and used as catalyst for the energy conversion. The as-synthesized PyCoPc/GO exhibits an efficient hydrogen evolution reaction due to the low overpotential ~253 mV at a 10 mA cm−2 current density with a Tafel slope ~96 mV dec−1 in alkaline media. Our study reveals that the active area of the catalyst was controlled with the help of π − π stacking interaction between GO and PyCoPc. Technologically, a highly efficient PyCoPc catalyst was developed for hydrogen evolution reaction.

The 21st-century world has seen several natural calamities in the form of widespread diseases such as SARS outbreak (2002-2004), swine flu pandemic (2009), and now the Covid-19. The outbreak of coronavirus has put the world in a state of anxiety and fear. As a result, a considerable social myths content has been disembarked as a dynamic response to the pandemic. Like elsewhere, the social media discourse on Covid-19 myths is being constructed and consumed in Pakistan. Considering Bouchard's concept of configuration of social myths as either "strictly contextualized" or having "universal features with loose ties to social mechanism," the investigation of the configuration of social myths of Covid-19 in Pakistani social media is explored. Furthermore, the myths were analyzed for co-relation and interconnectedness through intertextuality. The study propounds that the social media discourse of dominant social actors hailing from religious, social, and philosophical domains construe locally contextualized ideas of Covid-19. The social actors' coalition of all social myths set the scene for a Pakistani CovidArchemyth, which is intertwined with peculiarities of Pakistani tradition and culture.

The bismuth oxyselenide (Bi2O2Se) is considered as an alternative to graphene (zero band gap), black phosphorus, and molybdenum sulfide (MoS2) due to its sizeable band gap and high carrier mobility...

High energy density lightweight batteries are required to revolutionize the future electronics and electric vehicles, thus, a lightweight and flexible material having the ability to carry high energy is the need of the hour. Herein, we have used laser-induced graphene foam (LIGF), grown at polyimide, directly as a self-sustaining binder-free anode material for lithium-ion batteries. The migration of the electrons on the LIGF grown finally on the one side of polyimide makes it possible to directly implant as a device, for a proof of concept, a folded specimen of LIGF is used as an anode. The initial areal capacity of ∼203 μAhcm−2 for as-grown LIGF increases to 280 μA hcm−2 upon annealing at 400 °C because of the improved graphitization. Stable rate performance is observed for 100 cycles at a current density of 0.1 mAcm−1 with average Coulombic efficiency of 99%. The electrochemical impedance spectroscopy hint that the conductivity of the annealed specimen is increased subsequently favors faster electronic flow on the one side of a non-conducting polymer. The present study paves a path towards future LIGF based lightweight lithium-ion batteries and also enables flexible wearable high energy density storage devices.

Leukemia is a kind of blood cancer that influences people of all ages and is one of the leading causes of death worldwide. Acute lymphoblastic leukemia (ALL) is the most widely recognized type of leukemia found in the bone marrow of the human body. Traditional disease diagnostic techniques like blood and bone marrow examinations are slow and painful, resulting in the demand for non-invasive and fast methods. This work presents a non-invasive, convolutional neural network (CNN) based approach that utilizes medical images to perform the diagnosis task. The proposed solution consisting of a CNN-based model uses an attention module called Efficient Channel Attention (ECA) with the visual geometry group from oxford (VGG16) to extract better quality deep features from the image dataset, leading to better feature representation and better classification results. The proposed method shows that the ECA module helps to overcome morphological similarities between ALL cancer and healthy cell images. Various augmentation techniques are also employed to increase the quality and quantity of training data. We used the classification of normal vs. malignant cells (C-NMC) dataset and divided it into seven folds based on subject-level variability, which is usually ignored in previous methods. Experimental results show that our proposed CNN model can successfully extract deep features and achieved an accuracy of 91.1%. The obtained findings show that the proposed method may be utilized to diagnose ALL and would help pathologists.

Rare earth (RE) materials such as neodymium (Nd) and others consist of unique electronic configurations which result in unique electronic, electrochemical, and photonic properties. The high temperature (>1100 °C) growth and low active surface areas of REs hinder their use as an efficient electrocatalyst. Herein, different morphologies of Nd were successfully fabricated in situ on the surface of graphene using a double-zone chemical vapor deposition (CVD) method. The morphology of the Nd material on graphene is controlled, which results in the significant enhancement of the large specific surface area and electrochemical active area of the composite material due to the spatial morphology of Nd, thereby improving the hydrogen evolution reaction (HER) performance in an alkaline medium. The significantly enhanced HER activity with an overpotential of 75 mV and a Tafel slope of 95 mV dec-1 at a current density of 10 mA cm-2 is observed in Nd-GF. Mainly, a high specific surface area of ∼2217 cm2 g-1 and the porosity of graphene play major roles in the enhancement of activity. Thus, the present work provides a new strategy for the neodymium engineering synthesis of efficient rare earth-graphene composite electrocatalysts with a high electrochemical active area.

Graphene derivatives are useful in sensing applications owing to the exciting electrical, chemical, mechanical and structural properties. In this regard, graphene foam (GF) might have fruitful influence for sensing applications due to its porous morphology. However, lack of surface functionalities bottleneck its use in gas sensors but graphene oxide (GO) contains surface functionalities which have already been very useful for sensing application point of view. Herein, we fabricated GF via Chemical Vapor Deposition and GO via Hummers method. Both GF and GO are accessed by using different characterization tools and GO coated GF is used for sensing different alcohols (i.e. Isopropanol, Ethanol, and Methanol). The GO/GF system is highly sensitive to isopropanol due to the presence of high/low energy binding sights on the surface and molecular structure of isopropanol.

Morphotropic phased boundary (MPB) existent Bi0.5(K0.2Na0.8)0.5TiO3:xwt%MnO2 (BKNT:xMn) ceramic system is fabricated to investigate the ferroelectric and piezoelectric properties. All the ceramic samples have maintained the tetragonal (P4mm)-rhombohedral (R3c) structural duality due to MPB regional investigation of BKNT. The addition of MnO2 in BKNT has improved the multifunctional properties of the material at x ​= ​0.15. BKNT:0.15Mn ceramic has shown the maximum density of 6.98 ​g/cm3, remnant polarization (Pr) ​∼ ​32.5 ​μC/cm2, high impedance of ∼108 ​Ω, d33 of 206 ​pC/N, which are much improved properties than pure single phase BKNT and Bi0.5K0.5TiO3 ceramics. The dependence of dielectric constant (er) on temperature suggests the relaxor behavior and the high Curie temperature (TC) ​∼ ​410 ​°C for BKNT:0.15Mn ceramic, higher than the TC ​∼ ​360 ​°C of pure BKNT ceramic. The poled ceramics have maintained the stable piezoelectric properties till 300 ​°C. The introduction of multivalence Mn has improved the multifunctional properties of the material significantly, making it a strong candidate to be utilized in actuators and sensors.

In present work, Nickel (Ni) substituted Mn-Co ferrite nanoparticles, with doping content varying from 0 to 0.1, have been synthesized. The inverse spinel structure of doped cobalt ferrite has been claimed by X-ray diffractometer with average particle size of 20 nm. The decrease in lattice parameter and increase in X-ray density has been found with increase in Ni concentration in ferrite structure. Fourier transform infrared spectroscopy analysis showed two vibrational frequency bands (υ1 and υ2) for octahedral and tetrahedral sites depicting the formation of spinel ferrite. In addition, Transmission electron microscopy analyses were carried out to investigate particle size, which indicates that TEM and XRD analyses are in agreement. Magnetic analyses depict that coercivity value increases from 635 Oe to 841 Oe in Ni doped Mn-Co ferrite. Exchange interactions between Ni and Mn0.2Co0.8-xFe2O4 result for enlargement in coercivity and shift in hysteresis loop towards positive direction along the field axis. The increment in magnetic coercive field and exchange bias has been observed as temperature decreases. Enhanced magnetic properties at low temperature are attributed to magneto-crystalline anisotropy and surface effects.

A significant research topic in the area of computational social choice is the complication of different kinds of dishonest behaviour like manipulation, dominance and bribery. Whereas most of the work on this issue assumes that the opposite party has incomplete knowledge regarding every agent, they did not know the true preferences of other voters. We have analysed the dynamics of voting rules with the help of some manipulative and non-manipulative moves. Voters have incomplete information. The voters are aware of the winner at every stage and they make short term rational decisions. The number of candidates and voters are small, and the decisions need to be made quickly. We want the better reply as low as possible while keeping the best reply as high as possible. The voting rules we have used are Plurality rule and Borda rule. We have analysed the dynamics for these two voting rules for small number of voters and candidates.

Highly ordered and reproducible Gd nanowires have been reported via DC electrodeposition method. In this regard, templates with different diameters 100 nm, 50 nm and 20 nm were utilized. Shape morphology, reproducibly and homogeneity of nanowires were investigated with field emission scanning electron microscopy (FE-SEM). Morphological analyses confirm as required diameter, length and aspect ratio. Structurally, body centered cubic (bcc) phase was observed with Rietveld refinement of X-ray diffraction (XRD) patterns for all diameters. Magnetic investigations are including zero field cooled (ZFC) and field cooled (FC) and hysteresis measurement by using physical property measurement system (PPMS). These magnetic analyses of nanowires embedded in AAO templates predict mix phase with superparamagnetic and ferromagnetic clusters.

Graphene foam (GF) infiltrated with polymer attracts researchers toward practical pressure sensing applications, especially tactile sensors. However, interface between polymer and graphene plays a vital role under a specific type and amount of pressure. Herein, we have investigated the impact of static and dynamic pressure upon GF-polymer. A recovery time of ∼ 0.1 s is detected during static pressure sensing. Unlike static pressure, GF-polymer samples are highly sensitive to dynamic load, and a quick recovery time ∼ 0.06 s is detected. The sensitivity of the dynamic pressure sensor ∼ 1.17 ± 0.1 Pa−1 is almost double compares to the sensitivity of the static pressure sensor ∼ 2.1 ± 0.3 Pa−1. Technologically, tactile sensors exert pressure in different forms and GF-polymer is an excellent choice for forming a pressure sensor. The present study will help develop efficient tactile sensors.

Polypyrrole (Ppy) is coated on titanium dioxide nanotubes arrays (TNAs) by using electrochemical method. Both TNAs and TNAs/Ppy are used as free-standing anode material in lithium-ion batteries (LiBs). The as-grown TNAs anode-based LiB shows a specific capacity ∼ 207 μA h cm−2, which is enhanced ∼ 330 μA h cm−2 significantly with the introduction of Ppy. A stable columbic efficiency ∼ 99.9 % and an excellent rate performance is observed in TNAs/Ppy based LiBs.

The synergetic effect of hydrophilic and hydrophobic carbon can be used to obtain tunable hydrogen evolution reaction (HER) at the interface. Herein, graphene oxide (GO-Hummers method) was coated on graphene foam (GF) synthesized via chemical vapor deposition to develop mixed-dimensional heterostructure for the observation of HER. The porosity of GF not only provides an optimized diffusion coefficient for better mass transport but also modified surface chemistry (GF/GO-hydrophobic/hydrophilic interface), which results in an onset potential 50 mV and overpotential of 450 mV to achieve the current density 10 mA/cm2. The surface analysis shows that inherent functional groups at the surface played a key role in tuning the activity of hybrid, providing a pathway to introduce non-corrosive electrodes for water splitting.

A significant research topic in the area of Computational Social Choice is the complication of different kinds of dishonest behavior like manipulation, dominance and bribery. Whereas most of the work on this issue assumes that the opposite party has incomplete knowledge regarding every agent, they did not know the true preferences of other voters. We have analyzed the dynamics of voting rules with the help of some manipulative and non-manipulative moves. Voters have incomplete information. The voters are aware of the winner at every stage and they make short term rational decisions. The number of candidates and voters are small, and the decisions need to be made quickly. We want the better reply as low as possible while keeping the best reply as high as possible. The voting rules we have used are Plurality rule and Borda rule. We have analyzed the dynamics for these two voting rules for small number of voters and candidates.