This study examines whether hydrogen peroxide (H2O2) addition extends lean rotating-detonation operation while preserving pressure-front coherence. Two-dimensional transient reacting-flow simulations were performed for 38 lean conditions in a premixed nitrogen-diluted H2-O2 rotating detonation engine, spanning equivalence ratios of 0.550-0.700 with case-dependent H2O2 addition. Propagated states were assessed using wave velocity relative to the case-specific Chapman-Jouguet (CJ) value, dominant high-pressure-component fraction, front-disruption events, upper-tail pressure intensity relative to the case-specific Zel'dovich-von Neumann-Doring (ZND) pressure, mean OH mass fraction, and pressure-OH spatial coupling. Within the sampled matrix, H2O2 addition extended observed lean propagation from cent = 0.700 to phi = 0.560. All propagated cases retained detonation-like velocities, with U-x/U-CJ = 0.892-0.930, but velocity alone did not distinguish coherent-front from transverse-wave or front-disrupted propagation. Coherent-front cases exhibited a more dominant pressure structure, fewer disruption events, near-reference upper-tail pressure intensity, and near-unity pressure-OH coupling. Mean OH increased monotonically with H2O2 addition within each equivalence-ratio series, whereas pressure-OH coupling provided the clearest separation among the diagnostics evaluated within this two-dimensional matrix. Sensitised lean operability should therefore be assessed using coupled propagation, pressure-topology, and OH-field diagnostics rather than wave survival or velocity alone.
Bio-based phase change materials (PCM) such as fatty acids, fatty alcohols and fatty esters are attractive candidates for photovoltaic-thermal (PVT) systems because they combine sustainability, chemical stability and tuneable melting ranges that overlap typical PV operating temperatures across many climates. However, their intrinsically low thermal conductivity and limited spectral absorption restrict charge-discharge rates and thus the extent of PV temperature regulation and useable heat recovery. This work investigates the role of nanocomposite enhancement in tailoring the thermo-physical and optical properties of fatty acid-, alcohol-, and ester-based PCM for climate-specific PVT operation. Drawing on recent experimental and modelling studies of nano-enhanced PCM (NePCM) in PVT collectors, we examine how nanofillers can be combined with bio-PCM to align melting temperature with PV operating windows defined by PV-centric climate maps while increasing the thermophysical properties. Direct evidence on climate-specific PVT-PCM integration remains scarce, so this review adapts established tailoring principles from other thermal-storage applications and organises them against the Köppen-Geiger-PV (KGPV) climate classification. These findings motivate a climate-resolved, materials-by-design framework that couples eutectic composition and nanofiller type to local irradiance and temperature statistics, enabling a coherent basis for future research on rational design of nano-enhanced fatty acid, alcohol and ester PCM for next-generation climate-specific PVT applications.
Municipal solid waste (MSW) recovery is critical to global decarbonization agendas. Existing studies have provided important insights into the environmental performance of alternative waste-treatment pathways through life-cycle and scenario-based assessments. However, less is known about whether recovery expansion translates into measurable reductions in observed carbon emissions. This study employs an instrumental-variable framework to estimate the economy-wide carbon-emission effects of MSW recovery using a 32-country panel from 1998 to 2023, addressing reverse-causality concerns in the recovery-emission relationship. The results show that, across the 32-country sample, a 10% increase in aggregate MSW recovery is associated with an average 0.95–1.15% reduction in per capita carbon emissions. This estimate reflects the net system-level effect of recovery expansion under the observed mix of recovery pathways and national conditions, rather than a common effect of individual recovery technologies. The effect varies substantially across recovery systems: energy-recovery-dominated systems show stronger mitigation effects than recycling-dominated systems, with further differences across recovery scale, energy structure, and socioeconomic conditions. Finally, selected non-sample countries are compared with the 32-country sample across key structural moderators to identify where recovery expansion is most likely to deliver large mitigation gains. Overall, the study provides cross-country causal evidence on how MSW recovery translates into economy-wide emission outcomes under different national conditions, offering a system-level basis for aligning recovery strategies with broader decarbonization goals.
Long Range (LoRa) networks have emerged as a vital solution catering to applications requiring coverage over relatively long distances in the world of Internet of Things (IoT), where connectivity and efficient data transmission are paramount. LoRa’s utilization of the unlicensed Industrial, Scientific, and Medical (ISM) band not only underscores its cost-effectiveness but also positions it favorably against licensed technologies in terms of deployment cost. Consequently, LoRa has been used as the underlying communication technology for applications across various industrial IoT scenarios. Despite its immense promise in reshaping IoT connectivity, LoRa does have some shortcomings and challenges that the research community has yet to address to unleash its full potential. These limitations have triggered substantial attention from diverse entities, including research institutions, organizations, and industry stakeholders. This paper reviews the literature aimed at improving the capacity and scalability of LoRa networks specifically at the Medium Access Control (MAC) and data link layers. Unlike other surveys, this study focuses on these layers because they play a pivotal role in managing collision rates, which significantly impact network scalability. The paper suggests a comprehensive review of the literature, organizing it based on key limitations that could hinder the network’s ability to meet its performance objectives, including scalability, Packet Delivery Ratio (PDR), and energy efficiency. In addition, the paper provides a summary of these research efforts and offers insight into potential directions for future research in this area.
Although corporate branding has gained substantial interest in both academic and service sectors, the airline industry literature has ignored the influence of corporate brand dimensions on passenger behavior, particularly through mediating mechanisms. To address this research gap, the present study investigates the direct effects of corporate brand dimensions on passenger satisfaction and loyalty. In addition, this study examines the mediating roles of positive passenger experience and trust in the relationships among corporate brand dimensions, passenger satisfaction, and loyalty. Data were collected by using a convenient sampling technique from 514 airline passengers at three major airports in Pakistan. The study hypotheses were tested using PLS-SEM with SmartPLS-4. The results indicate that corporate brand dimensions positively and significantly influence passenger satisfaction and loyalty. The results also revealed the positive and significant role of mediating variables in the relationship between corporate brand dimensions, passenger satisfaction, and loyalty.
