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This study presents Density Functional Theory (DFT) investigation into the hydrogen storage capabilities of B6N6 nanoring. Utilizing the ωB97XD functional and def2TZVP basis set, this research explores the geometric, energetic, and electronic properties of the B6N6 nanoring, highlighting its potential as an efficient material for hydrogen storage. In‐depth analyses of the HOMO‐LUMO electronic density, Natural Bond Orbital (NBO) charge, Non‐Covalent Interactions (NCI), and Density of States (DOS) are conducted to understand the electronic structure changes during hydrogen adsorption. Furthermore, the desorption temperatures of hydrogen from the B6N6 nanoring, as calculated through the Van't Hoff equation, fall within a range considerably higher than the critical point of hydrogen. This finding indicates the practical feasibility of the B6N6 nanoring in hydrogen storage applications. Notably, the hydrogen storage capacity, measured in terms of gravimetric density, shows a significant increase with the addition of hydrogen molecules, reaching a maximum of 9.77% for 8H2 adsorbed on B6N6. Overall, this study underscores the B6N6 nanoring as a promising candidate for addressing the current challenges in hydrogen storage, particularly in terms of capacity, stability, and operational temperature. [ABSTRACT FROM AUTHOR]

The nexus between climate change and military security is essentially non-existent in Pakistan's security discourse. The paper argues for the connection between these two sectors - from the Copenhagen School framework of security - and presents how threats from climate change threaten Pakistan's military security. Most notable threats, in severity and frequency, are sea level rise, cyclone risks, drastic floods, warming patterns, and glacial melting. Sea level rise and cyclone risks impact naval assets and infrastructure while warming patterns and glacial melting affect troop movement, deployments, and logistics. Resultantly, military training, force capacity, and operational readiness is affected. Threats are more potent in strategically significant locations (Siachen, Sindh, and Punjab) which house important forward military bases. The paper provides actionable recommendations that create foundations for future steps as well. [ABSTRACT FROM AUTHOR]

The Treaty on Prohibition of Nuclear Weapons (TPNWs) was negotiated with the primary purpose of creating a new international norm that could bring pressure upon all the nuclear possessor states to work towards nuclear disarmament. Instead, the TPNW may have led to more divisions between the nuclear weapon states (NWS) and the non-nuclear weapon states (NNWS) that could affect the outcome of the 2020 NPT (Nuclear Non-proliferation Treaty) Review Conference. Parallel initiatives with conflicting obligations, spearheaded by the nongovernmental organizations (NGOs) and negotiated amongst the NNWS mainly, without taking into consideration security interests of all states, are likely to reduce the incentive for the nuclear possessor states (both NPT and the non-NPT states) to remain constructively engaged with the non-proliferation regime, thus making the goal of nuclear disarmament more elusive. [ABSTRACT FROM AUTHOR]

In this study, camphorsulphonic acid-doped conducting polyaniline/silk fibroin (Pani/SF) composites were prepared by in-situ polymerisation. The Pani/SF composite fibres were characterised by using Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, thermogravimetric analysis, scanning electron microscopy and digital photographs. Results indicated that the Pani was successfully coated on silk fibroin. The electrical properties of Pani/SF composite fibres were influenced by the extent of loading of aniline monomers. The as-prepared material was studied as a sensing material by observing the change in their electrical conductivity on exposure to ammonia and acetaldehyde, followed by ambient air at room temperature. It was found that the composite fibres showed good reversibility and conductivity decreased on exposure to higher concentration of ammonia and acetaldehyde vapours at room temperature. [ABSTRACT FROM AUTHOR]

In this communication, we report the synthesis of polypyrrole (PPy) and polypyrrole/zirconia (PPy/ZrO2) nanocomposites by an in-situ chemical polymerisation method and their application as sensor for detection of ethene gas for the first time. The as-prepared PPy and PPy/ZrO2 nanocomposites were characterised by Fourier-transform infrared spectroscopy, thermogravimetric analysis, x-ray diffraction and scanning electron microscopy. The nanocomposite containing 20 wt.% of ZrO2 was found to possess higher DC (direct current) electrical conductivity than PPy and the other PPy/ZrO2 nanocomposites. Sensing response was calculated on the basis of change in DC electrical conductivity. The most conductive nanocomposite was found to be highly sensitive and reversible to ethene gas. This study indicates an effective approach to possible future sensing technology for the detection of ethene gas. [ABSTRACT FROM AUTHOR]

In the present work, a nanocomposite of boron nitride (BN) and silver nanoparticles (Ag) enwrapped by polypyrrole (PPy) has been synthesized for first time via in situ chemical oxidative polymerization of pyrrole using ferric chloride. The structures of synthesized FeCl 3 doped PPy, BN/Ag and PPy/Ag@BN nanocomposites were confirmed by fourier transform infrared spectroscopy, x-ray diffraction, thermogravimetric analysis, field emission scanning electron microscopy and transmittance electron microscopy technique. Our investigations showed that the electrical response of PPy/Ag@BN nanocomposite which contains a conductor (Ag), an insulator (BN) and a semiconductor (PPy), was greater than that of polypyrrole. The electrochemical supercapacitive performance shows that FeCl 3 doped PPy has higher capacitance than PPy/Ag@BN which might be due to higher conductivity of PPy as PPy/Ag@BN shows poor conductivity due to the insulating nature of BN. The newly synthesized nanocomposite showed rapid CO 2 sensing and significantly improved DC electrical conductivity. [ABSTRACT FROM AUTHOR]

We report the electrical properties and photocatalytic activity of polyaniline (Pani) and polyaniline/silk fibroin (Pani/SF) composite. The Pani/SF composite has been synthesized first time by chemical oxidative in-situ polymerization method by using potassium persulphate (K2S2O8) in an acidic medium. Thus prepared Pani and Pani/SF composite were characterized by using Fourier-transform infrared spectroscopy, x-ray diffraction, thermogravimetric analysis and scanning electron microscopy. The stability in terms of the DC electrical conductivity of Pani/SF composite and Pani was investigated under isothermal and cyclic aging conditions. Results indicated that the electrical properties of the composite were significantly influenced by the loading of SF to Pani and observed to be more thermally stable than those of Pani. As-prepared Pani and Pani/SF composites were studied for the degradation of methylene blue (MB) and Rhodamine B (RhB) under UV-light irradiations. The results showed that 91.4% & 85.4% degradation of RhB and MB takes place respectively after 90 min over Pani/SF composite. The decomposition rate of composite was 1.8-2.2 times greater than that of Pani. The improvement of photocatalytic activity of composite may be attributed to the electron-sink function of silk fibroin which increases the optical absorption property and separation of photogenerated charge carriers than Pani alone. [ABSTRACT FROM AUTHOR]

This paper proposes a novel approach to decision-making based on a three-phase application of a new fuzzy logic model that embraces the principles of symmetry by balancing competing objectives in data collection and analysis. Our study, which employs a three-stage stratified random sample strategy with a randomized response technique, addresses the critical challenges of cost management and volatility reduction. Using the alpha-cut method, our model creates an effective allocation strategy that finds a balance between cost constraints and variance reduction objectives. We use numerical examples from real-world scenarios to demonstrate our approach's durability and practicality. Our revolutionary technique maintains data quality and cost-effectiveness while offering a game-changing answer to sensitive information acquisition concerns. By combining randomized response techniques and fuzzy logic, this study establishes a new standard for decision-making models that prioritizes both data-gathering precision and privacy preservation, encapsulating the essential principle of symmetry in balancing competing aims. [ABSTRACT FROM AUTHOR]

Objective: To determine the prevalence of multivitamin supplement use among prescribed and non-prescribed population of Rawalpindi and Islamabad Pakistan. Study Design: It was a Quantitative analytical cross-sectional study. Place and Duration of Study: The study was carried out among general population of Rawalpindi and Islamabad Pakistan, from Jan till Apr 2022. Methodology: Nonprobability convenient sampling technique was used. The sample size was 385. The data was gathered through an online survey and was analyzed using IBM SPSS statistics version 25. Chi-square test was applied on qualitative variables with p-value significant at <0.05. Results: Only 41% of people were prescribed multivitamins by their doctors while 59% were self-medicated. An overall prevalence of multivitamin supplementation among the population was 66.9%. About 48.3% of people are aware of their harmful effects. Majority (88.1%) of population consider vitamins good for their health. 70% of people buy supplements via pharmacist and almost half of the people do not read the leaflets that come with supplements. Male gender was statistically significantly associated with awareness of vitamin supplement use and encouraging its use to others (p≤0.05). Conclusion: There exists a high prevalence of multivitamins use amongst the twin cities of Rawalpindi/Islamabad. Although most of the population had an awareness of what multivitamins are essentially, half the population do not know about the harmful effects of vitamins. Males had more awareness of multivitamins supplement use as compared to females. [ABSTRACT FROM AUTHOR]