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The melting enthalpy and melting temperature have a significant impact on the latent heat that results from phase change materials (PCMs) used for thermal energy storage. Among the PCMs that are currently on the market, inorganic salt hydrates have greater thermal conductivity and latent heat than organic PCMs. However, the problem of salt hydrates' degree of supercooling limits their use in energy storage devices. Using sodium carbonate decahydrate (SCD) and sodium phosphate dibasic dodecahydrate (SPDD), a low temperature inorganic-inorganic eutectic salt hydrate PCM with a higher melting enthalpy and intended phase transition temperature is developed in this research study. The eutectic SCD/SPDD salt hydrate PCM eutectic point and the eutectic composition of salt hydrate PCMs to operate at low temperature range is numerically determined using Schrader equation. By numerical methods we obtain the 68 wt% of SCD with 32 wt% of SPDD to exhibit eutectic SCD/SPDD composite with eutectic melting temperature of 26.2 °C and melting enthalpy of 210.6 J/g. The synthesised eutectic PCM are characterised to explore their chemical stability, latent heat, melting point and their shortcoming due to degree of supercooling. A good way to get around the problem of the supercooling degree is to disperse the nucleating agents. In order to assess the type and degree of supercooling, the produced eutectic PCM composition is experimentally evaluated at 1–10% utilising borax, alumina, and sodium sulphate dodecahydrate as nucleating agents. However, for building cooling applications PCM with minimal degree of supercooling, with the ability to release low enthalpy during discharging is an advantage.

Abstract Transportation sector is one of the core parts of modern civilization. Proper utilization of energy and exergy in this sector is necessary to ensure energy loss and environmental sustainability. Increasing exergy efficiency will reduce carbon emissions from this sector. Since 1970, Reistad estimates have been widely used to determine the energy and exergy efficiencies of this sector. However, the modern transport sector has undergone significant changes in recent decades. Hence, it is necessary to apply new Reistad estimates in determining the energy and exergy efficiencies. This is the first study to apply updated Reistad estimates to explore the energy and exergy efficiencies in the transportation sector of Bangladesh based on the data from 2000 to 2017. The overall exergy efficiency is significantly lower than the energy efficiencies as it ranges from 27.7% to 30.0%. Efficiencies are lower as the maximum portion of input exergy is lost to the environment. The road subsector needs major improvements as it is responsible for major amount of exergy loss. A comparison is made between conventional and updated estimates which highlights that the updated estimates provide more accurate results. Thus, it is recommended to apply updated Reistad estimates in determining the energy and exergy efficiencies of the transport sector.

MXenes possess unique features that are useful for broader industrial development. However, although many different compositions of MXenes have been discovered, little research has been conducted on the optimal synthesis strategy for producing the best MXenes yield. Therefore, substantial work is performed on the synthesis’ structure and property relationship for direct methanol fuel cell (DMFC) applications since MXenes have been successfully hybridised with rice husk ash (RHA). In this study, to produce titanium-based MXene, Ti3C2 nanopowders are added to the rice husk ash matrix to synthesise hybrid RHA/MXene composites (R-MX). Using different weight percentages of MXene hybridised with rice husk ash (2 wt. % R-MX, 4 wt. % R-MX and 6 wt. % R-MX), different electrochemical properties are obtained. Meanwhile, electrochemical analysis is undertaken to investigate the methanol oxidation performance using Linear Sweep Voltammetry (LSV). The highest percentage of the R-MX hybrid composite, 6 wt. % MXene, showed the lowest Tafel slope (148 mV/dec) and the highest ionic exchange current density in the same Tafel analysis. Moreover, the incorporation of MXene into RHA produced good results from the chronoamperometry analysis (CA), with the highest percentage of the hybrid composite, R-6MX, showing the highest retention rate of 97.28%. Meanwhile, the Nyquist plot analysis showed an increasing semicircle arc diameter at the lower-frequency region, implying a lower interfacial charge resistance upon the addition of MXene into RHA. This outcome corresponded to the CA and LSV analysis findings, R-6MX showed a remarkable performance in terms of having the highest peak current density of 0.9454 mA/cm2 and retention rate of 97.28%. Both of these values show that hybrid R-6MX was able to maintain a high current for the entire duration. The current is maintained in a stable form for some time, proving that R-6MX was the most stable, with a minimal corrosion reaction and tolerance in a methanol medium. The results from this study enabled an evaluation of the possibility of utilising low-cost, green RHA material for fuel cell applications to promote sustainability. The novelty of this work is that a cheap source of silica-based RHA, a type of waste material, is incorporated with MXene through hybridisation processes.

Without pure water, it is impossible to survive for any living beings. The ratio of freshwater on our planet is very poor and the demand is increasing with time for the growing population. Furthermore, water is being contaminated by industrial and agricultural activities, pharmaceuticals, technocratic civilization, pesticides, garments, global changes etc. In addition to this, environmental pollution and global warming are swelling due to the greenhouse and harmful gases generated from the dumping and burning of fossil fuel. Addressing these problems, it is necessary to find out the cost-effective and environmental friendly processes to purify the contaminated water and air. Activated carbons (ACs) are one of the best solutions for removing the pollutants from aqueous and atmosphere as it is the carbonaceous materials with a high degree of porosity, well-developed surface area, and distinguished functional groups which are required for elimination of contaminants. The preparations of activated carbon are easy and safe processes, mainly from the pyrolysis or gasification of biomass with heat and/or chemicals. The recycling and regeneration of activated carbon after use are also essential for resource maintenance and environmental safety. Thus, AC can protect the ecosystem in a double direction by purifying the water and air from the pollutants.

The current research focuses on formulating a new class of Therminol55-based nanofluids that incorporates an MXene/Al2O3 nanocomposite as the new class of dispersant at three different concentrations of 0.05, 0.10, and 0.20 wt%. The optical and thermophysical properties of the formulated nanofluid are assessed experimentally. Zeta potential and FTIR analyses are employed to evaluate the composite particles' surface charge and chemical stability, respectively. Thermal conductivity is observed to increase with nanoparticle loading and maximally augmented by 61.8% for 0.20 wt%, whereas dynamic viscosity increased with adding nanoparticles but remarkably dropped with increasing temperature. In addition, the prepared TH55/MXene + Al2O3 samples are thermally stable up to 200 °C according to TGA analyses. Moreover, the proposed correlations for the thermal conductivity and viscosity showed good agreement with the experimental data. The study’s findings suggest that the formulated nanofluid could be a viable contender to be used as a heat transfer fluid in the thermal sector.

Electric motors and boilers lead the industrial components which consume the largest portion of energy in an industry. This study explores the energy audit data of the condiment industry in India. The study mainly focuses on the estimation of the load factor, energy use, energy savings and annual bill savings with payback period of the electric motors of the plant. During the audit, it was found that there were several motors running under loaded conditions despite non-availability of variable speed drives installed in the plant. Therefore, variable speed drives are recommended to be installed to save energy by reducing the motors speed by up to 60%. According to the estimation, about 276 MWh, 551 MWh and 827 MWh electrical energy can be saved for 20%, 40% and 60% speed reduction of the motors using variable speed drives, respectively, where in most of the cases the payback period remains below 1 year. Furthermore, some suggestions are made to improve the poor power factor of running motors by using capacitor banks to save the reactive power. Besides, an estimation of energy saving is performed with a 2-ton capacity boiler. Since, there was no heat recovery system in the boiler; an air-preheater is suggested to be installed at the end of flue gas exhausting path of the boiler with the purpose of saving 68 tons of fuel per annum and having a payback period of 12 months. Moreover, a digital monitoring system, namely, “The Smart Joules” has been proposed to be installed in the plant aiming at saving about 3–5% of total energy per annum and having a payback period of 19 months. Finally, a summarization is made concluding in the fact that about 90 MWh energy and 95 tons of fuel can be saved (excluding motor energy savings) per annum by implementing proposed measures with a payback period of 15 months.

Abstract In this research, palm oil and soy oil were used as a natural polyol to prepare novel poly(silyl ether)s. Palm oil and soy oil were first converted to monoglyceride by one step via alcoholysis process in the presence of 0.1% CaO as a catalyst. The monoglycerides were characterized by Fourier transform infrared spectrometer (FT-IR), nuclear magnetic resonance (NMR) and iodine test. The novel poly(silyl ether)s were prepared via polycondensation reaction between dimethyldichlorosilane with monoglycerides based on palm and soy oils, respectively. FT-IR, NMR and silicone-29 (29Si NMR) were used to confirm and determine the presence of silicone in the synthesized polymers. Thermal behavior was studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Antibacterial activity of the polymers was screened against three different strains of bacteria, namely Escherichia coli E266, Staphylococcus aureus S276 and Salmonella choleeraesuis 10708.

The present research focused on the fabrication of biocompatible polyhydroxyalkanoate, chitosan, and hexagonal boron nitride incorporated (PHA/Ch-hBN) nanocomposites through a simple solvent casting technique. The fabricated nanocomposites were comprehensively characterized by Fourier transform infrared spectroscope (FT-IR), field emission scanning electroscope (FESEM), and elemental mapping and thermogravimetric analysis (TGA). The antibacterial activity of nanocomposites were investigated through time-kill method against multi drug resistant (MDR) microbes such as methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) K1 strains. In addition, nanocomposites have examined for their host cytotoxicity abilities using a Lactate dehydrogenase (LDH) assay against spontaneously immortalized human keratinocytes (HaCaT) cell lines. The results demonstrated highly significant antibacterial activity against MDR organisms and also significant cell viability as compared to the positive control. The fabricated PHA/Ch-hBN nanocomposite demonstrated effective antimicrobial and biocompatibility properties that would feasibly suit antibacterial and biomedical applications.

Drilled shafts are often subjected to various lateral loads due to earth pressure, wind loads and/or impact loads. Many studies have investigated the behavior of drilled shafts under lateral loads. However, there is limited study on the effect of cyclic loading on drilled shafts, which is of great importance during a hurricane strike. This paper encompasses a numerical study using three-dimensional (3D) finite difference software, FLAC3D, which investigated interaction between a drilled shaft and an MSE wall under cyclic loading event. The backfill material was simulated by a stress-dependent model, which can account for the hardening due to confining stresses. The interactions between dissimilar materials were represented by frictional interface at the contacts. The numerical simulation scrutinized the effects of soil friction angle and the loading cycles on the performance of the drilled shaft and MSE wall under both loading and unloading conditions. The result indicates that the cyclic loading leads to gradual accumulation of the displacement, which cannot be effectively considered in current design method.

Macrophages overexpress TET3 in endometriosis Macrophages are key immune cells in inflammation and tissue repair that contribute to the pathogenesis of endometriosis. Proinflammatory macrophages are actively recruited to endometriotic lesions, [...], Endometriosis, characterized by the presence of endometrial-like tissue outside the uterus, is a condition associated with pain and infertility. In this issue of theJCI, Lv et al. illuminate the critical pathophysiological role of the ten-eleven translocation 3 (TET3) in endometriosis. TET3 expression levels were higher in macrophages of endometriotic lesions compared with control endometrial tissue, implicating TET3 as a contributing factor in the chronic inflammation that occurs in endometriosis. TGF-pi and MCP1 are present in the peritoneal cavity of women with endometriosis, and macrophage exposure to these factors resulted in upregulation of TET3, thereby promoting their survival. Notably, Bobcat339, a selective TET inhibitor, induced apoptosis in these macrophages. Further, myeloid-specific TET3 loss reduced endometriosis in mice. RNA-Seq analysis following TET3 knockdown revealed alterations in cytokine signaling and cell-death pathways, underscoring the therapeutic potential of targeting TET3 in macrophages as a strategy for managing endometriosis.

The article presents a socio-geographical study of the prospects and challenges of sustainable tourism in Daman and Diu district in India. The study analyzes trends of domestic and foreign tourist arrivals in pre- and post-corona pandemic period. It evaluates prospects in heritage tourism, cultural tourism, advantages tourism, sports tourism and agro-tourism, as well as challenges including poor connectivity, poor infrastructure, lack of media coverage and alternative means of transport.