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The recent trend in research fosters the use of abundant seawater for modifying metal surfaces as electrode materials for energy generation, storage, transport, and water-splitting technologies. Economic and ecofriendly seawater is used as a solvent for modifying the surface of 3D nickel-foam (NiF) to Na2O–NiCl2@NiF as an electrode material in electrochemical supercapacitors and water-splitting electrocatalysis applications. The phase of the as-obtained Na2O–NiCl2 is confirmed from the proposed reaction mechanism, followed various physical measurement tests such as X-ray photoelectron spectroscopy and Fourier transform infrared analysis. The formation of Na2O–NiCl2 is caused by a high operation temperature and pressure of seawater solvent, the presence of lone pair electrons on oxygen, and more reactivity of Na for combining with dissolved oxygen than the lone-pair free Cl (towards Ni). In addition to exceptional HER and OER electrocatalytic activities, i.e., 146.3 mV cm−2 and 217 mV cm−2 at a scan rate of 5 mV s−1 to attain the 10 mA cm−2 current density, the Na2O–NiCl2 has demonstrated moderate energy storage ability with considerable durability, i.e., 2533 F g−1 specific capacitance at 3 A g−1 current density even after 2000 redox cycles. The as-assembled Na2O–NiCl2//Na2O–NiCl2 symmetric electrochemical supercapacitor device has ignited a "CNED" panel consisting of nearly forty LEDs with full brightness, offering applied importance in home appliances. In nutshell, seawater-modified metal surfaces can be used for energy storage and water-splitting applications. [ABSTRACT FROM AUTHOR]

The objective of the present study is to evaluate the performance, combustion, and emission characteristics of a compression‐ignition engine using hydrogen‐compressed natural gas (HCNG)‐enriched Kusum seed biodiesel blend (KSOBD20). The flow rate of HCNG was set at 5, 10, and 15 liters per minute (lpm), and the injection pressure was varied in the range of 180–240 bar. Brake thermal efficiency (BTE) and brake‐specific fuel consumption (BSFC) were improved when HCNG was added to the KSOBD20. Combustion characteristics, namely, cylinder pressure (CP) and net heat release rate (NHRR), were also improved. Emissions of carbon monoxide (CO), hydrocarbons (HC), and smoke were also reduced, with the exception of nitrogen oxides (NOx). The higher injection pressure (240 bar) had a positive effect on operating characteristics. At an injection pressure of 240 bar, for KSOB20 + 15 lpm HCNG, the highest BTE and the lowest BSFC were found to be 32.09% and 0.227 kg/kWh, respectively. Also, the CP and NHRR were 69.34 bar and 66.04 J/deg. CO, HC, and smoke levels were finally reduced to 0.013%, 47 ppm, and 9%, respectively, with increased NOx levels of 1623 ppm. For optimum results in terms of engine characteristics, the fuel combination KSOBD20 + 15 lpm HCNG at fuel injection pressure 240 bar is recommended. Thus, HCNG‐enriched KSOBD20 can be used as an alternative fuel in diesel engines without requiring any modifications to increase performance and reduce emissions. [ABSTRACT FROM AUTHOR]

In this study, effect of air annealing temperatures on electrocatalytic water splitting performance of the bismuth oxy-chloride (BiOCl) is investigated and explored. The BiOCl catalyst is chemically synthesized initially which is further air annealed at different temperatures viz., 50 °C, 150 °C, 300 °C, and 600 °C for knowing changes in the structure, surface morphology and electrochemical properties. The electrocatalytic activities like hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are systematically evaluated in alkaline medium where air annealing temperature has significant influence on the catalytic performance of the BiOCl. Along with excellent stability for prolonged electrolysis, the one annealed at 150 °C demonstrates a superior electrocatalytic activity having; low overpotentials of 286 mV for OER and 223 mV for HER at a current density of 10 mA/cm2, Tafel slopes of 114 mV/dec for OER and 106 mV/dec for HER than pristine and higher temperature annealed BiOCl catalysts. The enhanced catalytic performance of the 150 °C-annealed BiOCl catalyst is attributed to its improved crystallinity and unique surface morphology with reduced charge transfer resistance. [Display omitted] • Facile chemical synthesis of BiOCl nanostructures. • Structure, morphology and compositional analysis. • Influence of air-annealing on BiOCl structure and morphology. • Optimized annealing enhances BiOCl's electrocatalytic performance. • Outstanding HER, OER, and overall water splitting electrocatalytic activity. [ABSTRACT FROM AUTHOR]

The present work deals with the development of a MmNi4.5Al0.5‐based single bed sorption precooled Linde‐Hampson cryocooler. The working substance and the precooling refrigerant used in this investigation were hydrogen and liquid nitrogen, respectively. The gaseous hydrogen could be compressed merely in the metal hydride reactor in comparative ease and thus an MmNi4.5Al0.5‐based metal hydride reactor was used to develop a single bed sorption compressor. The hydrogen is allowed to compress at two different supply pressures of 5 and 10 bar at a constant absorption temperature of 20°C. Desorption temperatures were varied at 65°C, 75°C, and 80°C. Maximum discharge pressures were obtained at a desorption temperature of 80°C as 21 and 27 bar, respectively. The entire cryocooler was designed, fabricated, and tested on the sorption cryocooler. Furthermore, compressed high‐pressure gaseous hydrogen was allowed to flow in the cryocooler at a flow rate of 40 standard cubic centimeter per minute. The minimum temperatures obtained in the evaporator at discharge pressures of 21 and 27 bar were 111 K and 107 K, respectively. [ABSTRACT FROM AUTHOR]

In this investigation, the reaction of [Cu(2,2'-bpy)(H2O)4][ClO4]2 with thiosemicarbazide (tsc) yielded [Cu(2,2'-bpy)(NCS)2]n frameworks, which has crystallized in noncentrosymmetric space group (Cc). The complex has been characterized by elemental analyses, FT-IR spectrum, powder X-ray diffraction analysis and single-crystal diffraction analysis. This complex is 1D polymer with high thermal stability and showing positive cotton effect. These results have provided some interesting insights into its nonlinear optical applications. Solid state fluorescence spectrum shows broad photoluminescence emission bands, which are assigned as the bands of intra-ligand charge transfer and MLCT (metal to ligand charge transfer) transitions. During investigation of various intermolecular interactions, both single crystal X-ray diffraction and Hirshfeld surface analysis give comparable results. [ABSTRACT FROM AUTHOR]

The Cu(II) ion-based polymeric complexes [Cu(2,2′-bpy).(N3)2]n (I), [Cu2(2,2′-bpy)2.(N3)4]n (II), and monomeric complex [Cu(2,2′-bpy).(NO3)2].5H2O (III) have been synthesized with rigid (-N3) and aromatic (2,2′-bpy = 2,2′-bipyridyl) ligand. The rigid azide group is responsible for the formation of 1-D extended structures in complexes I and II where as in the case of complex III, a monomeric complex is formed due to lack of a bridging group like -N3, resulting in limitation in dimensionality. The thermal stability of the 1-D complexes is comparatively higher than monomeric complex III. Hirshfeld surface analysis has also been applied to investigate other weak interactions and compared with the results from single-crystal X-ray data. Due to the presence of paramagnetic metal centers and long metal···metal distances in complexes I and II and presence of lattice water molecules in complex III, decrease in luminescence intensities have been observed. To attain further insights into the aforementioned interesting species, some chemical concepts such as highest occupied molecular orbital-lowest unoccupied molecular orbital gap, electronic chemical potential, chemical hardness, and electrophilicity index, identified as a derivative of electronic energy, have also been emphasized employing the quantum chemical calculations in the framework of the density functional theory method using the M06-2X/ 6-31G** level of study. Further, these complexes have been used to synthesize copper nanoparticles by applying a green synthetic route. [ABSTRACT FROM AUTHOR]

A 29-year-old man presented with palpitations, shortness of breath, and orthopnea. After being admitted, he progressed to cardiogenic shock and respiratory failure, which required ventilator support and cardioversion. Subsequent evaluation revealed a fibromuscular membrane across the left artrium, requiring urgent corrective surgery. This case report highlights the importance of identifying and treating the relatively rare cor triatriatum. [ABSTRACT FROM AUTHOR]