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The automobile industry is shifting from internal combustion engine vehicles (ICEVs) to hybrid electric vehicles (HEVs) or electric vehicles (EVs) extremely fast. Our calculation regarding the most popular private car brand in Bangladesh, Toyota, shows that the life cycle cost (LCC) of a Toyota BZ3 (EV), USD 43,409, is more expensive than a Toyota Aqua (HEV) and Toyota Prius (HEV), but cheaper than a Toyota Axio (ICEV) and Toyota Allion (ICEV). It has been found that about a 25% reduction in the acquisition cost of a Toyota BZ3 would lower its LCC to below others. EVs can be a good choice for those who travel a lot. Changes in electricity prices have little effect upon the LCC of EVs. With the expected decline in the annual price for batteries, which is between 6 and 9%, and the improvement of their capacities, EVs will be more competitive with other vehicles by 2030 or even earlier. EVs will dominate the market since demand for alternative fuel-powered vehicles is growing due to their environmental and economic advantages. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells with protonic ion conducting electrolytes (H-SOFCs) are recognized and anticipated as eco-friendly electrochemical devices fueled with several kinds of fuels. One distinct feature of SOFCs that makes them different from others is fuel flexibility. Ammonia is a colorless gas with a compound of nitrogen and hydrogen with a distinct strong smell at room temperature. It is easily dissolved in water and is a great absorbent. Ammonia plays a vital role as a caustic for its alkaline characteristics. Nowadays, ammonia is being used as a hydrogen carrier because it has carbon-free molecules and prosperous physical properties with transportation characteristics, distribution options, and storage capacity. Using ammonia as a fuel in H-SOFCs has the advantage of its ammonia cracking attributes and quality of being easily separated from generated steam. Moreover, toxic NOx gases are not formed in the anode while using ammonia as fuel in H-SOFCs. Recently, various numerical studies have been performed to comprehend the electrochemical and physical phenomena of H-SOFCs in order to develop a feasible and optimized design under different operating conditions rather than doing costlier experimentation. The aim of this concisely reviewed article is to present the current status of ammonia-fueled H-SOFC numerical modeling and the application of numerical modeling in ammonia-fueled H-SOFC geometrical shape optimization, which is still more desirable than traditional SOFCs. [ABSTRACT FROM AUTHOR]

CSZM compounds were synthesized by dry chemistry route with 5, 10, and 15% dopant of Mg dopants in the Ce 0.8−2x Sm 0.2 Zrx Mgx O2−d, {x = 0.05, 0.1 & 0.15}. The newly investigated materials were physically, chemically, and electrochemically studied and have shown promising results. The CSZM was crystalized in a fluorite structure with a pure cubic phase in a space group Fm3m and cell parameter a = 5.401742 ° A and theoretical density from 7.6 to 8.9 after firing in the air with a final temperature of 1400 °C. Characterization of the structure and indexing of electrolyte materials were made after X-ray diffraction (XRD) testing. A Scanning electron microscope (SEM) morphological analysis was used to examine the microstructure details. Electrochemical impedance spectroscopy (EIS) measurements were performed from 400 °C to 700 °C which show the highest conductivity value of 1.0461 × 10+1 S/cm at 700 °C. In comparison, the minimum value was 2.7329 × 10−2 S/cm at 400 °C, and the total activation energy (Ea ° A ) was found to be 0.6865 eV under 5% H2/Ar. [ABSTRACT FROM AUTHOR]

Highlights: NiO–BCZY powder prepared by citrate sol–gel method has homogenous particles; NiO–BCZY powder showed an average particle size of 51 ± 16 nm; NiO–BCZY powder calcined at 1100 °C showed a cubic phase without any impurities; The conductivity of anode sintered at 1200–1400 °C was 443–1124 S/cm at 800 °C; Anode sintered at 1400 °C exhibited the lowest ASR of 1.165 Ω cm2 at 800 °C. Understanding the impact of sintering temperature on the physical and chemical properties of Ni-BaCe0.54Zr0.36Y0.1O3-δ (Ni-BCZY) composite anode is worthy of being investigated as this anode is the potential for protonic ceramic fuel cell (PCFC) application. Initially, NiO–BCZY composite powder with 50 wt% of NiO and 50 wt% of BCZY is prepared by the sol–gel method using citric acid as the chelating agent. Thermogravimetric analysis indicates that the optimum calcination temperature of the synthesised powder is 1100 °C. XRD result shows that the calcined powder exists as a single cubic phase without any secondary phase with the lattice parameter (a) of 4.332 Å. FESEM analysis confirms that the powder is homogeneous and uniform, with an average particle size of 51 ± 16 nm. The specific surface area of the calcined powder measured by the Brunauer–Emmett–Teller (BET) technique is 6.25 m2/g. The thickness, porosity, electrical conductivity and electrochemical performance of the screen-printed anode are measured as a function of sintering temperature (1200–1400 °C). The thickness of the sintered anodes after the reduction process decreases from 28.95 μm to 26.18 μm and their porosity also decreases from 33.98% to 26.93% when the sintering temperature increases from 1200 °C to 1400 °C. The electrical conductivities of the anodes sintered at 1200 °C, 1300 °C and 1400 °C are 443 S/cm, 633 S/cm and 1124 S/cm at 800 °C, respectively. Electrochemical studies showed that the anode sintered at 1400 °C shows the lowest area specific resistance (ASR) of 1.165 Ω cm2 under a humidified (3% H2O) gas mixture of H2 (10%) and N2 (90%) at 800 °C. Further improvement of the anode's performance can be achieved by considering the properties of the screen-printing ink used for its preparation. [ABSTRACT FROM AUTHOR]

Nanostructured materials have gained much attention in recent engineering and material- science research due to their unique structural makeup, which stands them out from their bulk counterparts. Their novel properties of tiny-size structural elements (molecules or crystallites, clusters) of nanoscale dimensions (1 to 100 nm) make them a perfect material for energy applications. The recent keen interest in nanostructured materials research by academia and industrial experts arises from the unique variable characteristics of increased electrical and thermal conductivity. This occurs as nanostructured materials undergo a transient process from infinite-extended solid to a particle of ascertainable numbers of atoms. The commercial and energy sectors are very interested in developing and expanding simple synthetic pathways for nanostructured-electrocatalysts materials to aid in optimizing the number of active regions. Over the decades, various techniques have been put forward to design and synthesize nanostructured-electrocatalysts materials for electrochemical generation of energy and storage applications. As a result, the design of fuel cells, supercapacitors, and energy-storage devices has advanced significantly. This review provides a comprehensive outlook of various synthesis techniques and highlight the challenges of nanostructured- electrocatalysts materials application in fuel cells. Several synthesis methods are discussed and summarized for enhanced nanomaterial preparation and high product attainment with the sol-gel synthesis method being emphasized. The design methodology for an effective nanostructured electrocatalysts with high efficiency for fuel cells was also discussed. [ABSTRACT FROM AUTHOR]

Summary: The configuration of an external solar dish improves the performance of stepped slope solar still (SS) in an experimental setting. The use of an external solar dish raises the effects of the water basin, resulting in a higher rate of evaporation. The stepped still was designed, built, and tested in Ismailia, Egypt, using local weather conditions. The proposed SS had a 1 m2 base area and eight steps, a solar dish with a concentration ratio of 80, a cone tank, two centrifugal pumps, four photovoltaic modules totaling 1000 W, a control unit, and solenoid valves. The impact of utilizing the storage material during the phases was investigated. A nozzle was installed at the top of the cone tank. Four mass flow rates of circulated water were examined 250, 350, 450, and 550 mL/min. The control unit receives inputs from the photovoltaic output, photodiodes, and water temperature inside the cone. The control unit outputs the signal for the two solar dish motors, centrifugal pumps, and solenoid valves. First, a standard stepped SS, second, a stepped SS using phase change material (PCM), and finally, a stepped SS using PCM combined with a solar dish were investigated. The conventional stepped SSs with PCM had an optimal mass flow rate of 250 mL/min, whereas the stepped SS integrated with the solar dish had 550 mL/min of mass flow rate (an optimum value). The highest daily freshwater productivity was 7.63, 9.18, 11.23, and 13.9 kg/d for water spraying mass flow rates of 250, 350, 450, and 550 mL/min, respectively, with 0.0161 $/L/m2 of a maximum projected cost, according to data from an integrated stepped SS. [ABSTRACT FROM AUTHOR]

Summary: The performance of a single‐slope solar still system has been improved with the addition of copper oxide (CuO) nanopowder in water as nanofluid and thermoelectric glass cover cooling combination. The use of vibration further enhances the performance of distillate water as a result of the accelerated heat transfer. In this study, CuO nanofluids loaded the solar still system at volume concentrations of 0.5%, 1%, and 1.5%. The design, fabrication, and testing of the single still were conducted under the local weather conditions of Alexandria, which is located in the northwest of Egypt. The proposed solar still had a base area of 1 m2 and fitted with four coiled springs, a DC motor, and a photovoltaic (PV) solar panel. The vibration generator was a three‐phased, with a 1‐HP power motor (220 V, 50 Hz, and 1380 rpm maximum speed) fixed to a compact disk with a small punch for adding masses to generate the un‐mass balance forces. The power source for the DC motor was a 250‐W PV. The daily output of fresh water during the experimental period was empirically measured under the same climate conditions, and the results were compared with those of a conventional solar still. The daily rates of freshwater productivity were investigated in two cases: (a) under vibration without cover cooling and (b) under vibration with cover cooling at the three given nanofluid volume concentrations. Based on the results, the highest daily freshwater productivity attained with the vibration and cover cooling (at the 1.5% nanofluid volume concentration) 7.13, 4.97, and 3.36 kg/day, and the daily efficiency increases by 54%, 43% and 36% compared to the conventional case at the water depths of 10, 20, and 30 mm, respectively, with a maximum estimated cost of 0.027653$/L/m2. [ABSTRACT FROM AUTHOR]

Background: Surgical treatment of pterygium can result in corneal topographic changes. It is not clear that those changes are universal or technique dependent. Objectives: Evaluation of corneal topographic changes following pterygium surgery using sutured conjunctival autografting versus sutured amniotic membrane grafting. Patients and methods: In this prospective randomized study, patients suffering from primary pterygia that extend between two and four millimeters over the cornea were included. Patients were separated into group I; underwent pterygium excision with sutured conjunctival autograft, and group II underwent pterygium excision with sutured amniotic membrane graft after a comprehensive ophthalmic examination. The following topographic parameters were noted: the axial curvature map, elevation posterior map, and corneal thickness map. Results: Significant improvement of the mean visual acuity measured using the logMAR test was found in both groups postoperatively. The improvement included UCVA and BCVA as well as anterior keratmetric and cylindrical power of the cornea without significant dissimilarity between study groups. No statistically considerable changes in the posterior corneal surface or the corneal thickness were found. Conclusions: Pterygium excision can cause changes in the keratmetric and cylindrical power of the cornea without the affection of the posterior corneal surface or the corneal thickness. The corneal topographic changes caused by the pterygium were not varied with the type of surgical technique used. [ABSTRACT FROM AUTHOR]

Conventional solid oxide fuel cells (SOFCs) are operable at high temperatures (700–1000 °C) with the most commonly used electrolyte, yttria‐stabilized zirconia (YSZ). SOFC research and development activities have thus been carried out to reduce the SOFC operating temperature. At intermediate temperatures (400–700 °C), barium cerate (BaCeO3) and barium zirconate (BaZrO3) are good candidates for use as proton‐conducting electrolytes due to their promising electrochemical characteristics. Herein, two widely studied proton‐conducting materials with two dopants are combined and an attractive composition for the investigation of electrochemical behaviors is discovered. Ba0.9Sr0.1Ce0.5Zr0.35Y0.1Sm0.05O3−δ (BSCZYSm), a perovskite‐type polycrystalline material, has shown very promising properties to be used as proton‐conducting electrolyte at intermediate temperature range. BSCZYSm shows a high proton conductivity of 4.167 × 10−3 S cm−1 in a wet argon atmosphere and peak power density of 581.7 mW cm−2 in Ni–BSCZYSm | BSCZYSm | BSCF cell arrangement at 700 °C, which is one of the highest in comparison with proton‐conducting electrolyte‐based fuel cells reported until now. [ABSTRACT FROM AUTHOR]

The main emphasis of this work is to create a new perovskite material with three different compositions (La0.75Sr0.25Mn0.5Cr0.5−xAlxO3, x = 0.1, 0.2, 0.3) applied in both Intermediate‐ and High‐temperature Solid Oxide Fuel Cells (IT‐ and HT‐SOFCs). Perovskite‐type polycrystalline La0.75Sr0.25Mn0.5Cr0.5−xAlxO3−δ (x = 0.1, 0.2, 0.3) powders were synthesized and formed in a single phase structure by a dry chemistry route (standard solid‐state reaction method). The effect of Al doping on physicochemical and surface properties has been discovered. The compounds were crystallized in single phase rhombohedral symmetry (R‐3C Space. Group). Total conductivity of Al doping in wet 5% H2 was higher than both dry 5% H2 and air. The obtained results enhance the electro‐catalytic performance and the material conductivity as well, which will be good for anode materials in IT‐ and HT‐SOFCs and the optimum doping is 10%. [ABSTRACT FROM AUTHOR]

Purpose The aim was to compare between two techniques of diode laser transscleral cyclophotocoagulation in treatment of refractory glaucoma, that is, standard titratable (audible pops' technique) versus slow coagulation technique, regarding and efficacy. Patients and methods In this prospective randomized study, 40 patients with refractory glaucoma were divided into two study groups: group A underwent standard technique of diode laser transscleral cyclophotocoagulation (audible pops technique), and group B underwent slow coagulation technique of diode laser transscleral cyclophotocoagulation. Patients were followed up at 1 week, 1 month, 3 month, and 6 month duration postoperatively, and changes in visual acuity, intraocular pressure (IOP), as well as postoperative complications were documented. Results The mean IOP was reduced significantly from 46.3±8.9 to 18.9±5.45 mmHg in patient of group A and from 42.8±8.53 to 20.05±8.28 mmHg in patient of group B at the end of 6-month follow-up (P<0.0001). The mean number of postoperative antiglaucoma drugs needed to control IOP was also reduced significantly in both groups. No serious complications such as hypotony were reported in the two study groups. Conclusion Both techniques of diode transscleral cyclophotocoagulation were of near equal safety and efficacy in treatment of refractory glaucoma with different underlying etiologies. Both had good efficacy in IOP lowering, reduced number of antiglaucoma medications used by patients, and relieved pain, with near equal incidence of postoperative complications. [ABSTRACT FROM AUTHOR]

Background Shivering is one of the most stressful complications for patients and surgeons during spinal anesthesia. In this prospective, randomized, double-blinded study, we compared the efficacy of dexmedetomidine versus granisetron for control of postspinal shivering. Methods This study was conducted on 120 patients, ASA I-III, of either sex, aged 18-60 years, who were scheduled for elective lower limb and lower abdominal surgeries under spinal anesthesia. The response rate, time taken to control shivering, recurrence rate, and adverse effects were recorded. Results Incidence of shivering in 1127 patients was 52.7% (594 patients): we studied 120 patients; 28 patients (2.5%) developed grade 4 and 92 patients (8.2%) developed grade 3 shivering. There were no statistically significant differences regarding the time for onset of shivering, severity, response rate, need for a second dose, or pethidine between the two groups. However, time to control shivering was shorter in the dexmedetomidine group, with a higher recurrence rate. Incidences of hypotension, bradycardia, and sedation were higher in the dexmedetomidine group. However, there was no incidence of severe bradycardia or respiratory depression in our study. Conclusion Both dexmedetomidine and granisetron effectively reduce postspinal shivering without any major adverse effects. However, dexmedetomidine has rapid onset and short duration, whereas granisetron has less hemodynamic alterations. [ABSTRACT FROM AUTHOR]

A layered perovskite, NdBaMn 2 O 5+δ (NBMO), was synthesized by solid state reaction method in air. Rietveld analysis of X-Ray Diffraction (XRD) data showed the material crystallizing in orthorhombic symmetry ( Pmmm space group). Scanning electron microscopy (SEM) was used to check the morphology and, the analysis of the micrographs exhibited a porous structure with in-situ growth of nanoparticles. Electrochemical Impedance Spectroscopy (EIS) measurements from 600 °C to 800 °Cshows the highest conductivity value of 1.17 × 10 −1 S/cm obtained at 800 °C with low activation energy (E a ) of 0.3 eV in air. In 5% H 2 /Ar gas mixture, the conductivity and activation energy values were 1.97 × 10 −2 S/cm and 0.4 eV, respectively at 800 °C. The DC conductivity measurements also showed that this material is highly conductive in air with a conductivity value of 0.75 S/cm at 850 °C. Dual chamber fuel cell measurements on Ni-YSZ/YSZ/NBMO cell using 5% H 2 /Ar as fuel (from 700 °C to 800 °C) showed a maximum power density of 0.202 W/cm 2 at 800 °C. The relatively high conductivity of the material in air and low activation energy makes it a potential candidate as cathode for solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

The production of hydrogen from glucose by using Enterobacter aerogenes ATCC 13048 ( E . aerogenes ) in an immobilized cell reactor (ICR) was investigated. The effect of several factors, such as the glucose concentration, feed flow rate, and fermentation time were examined. The highest amount of hydrogen (9.44 mmol H 2 /g glucose) was obtained at a glucose concentration of 8 g/L, flow rate of 0.5 mL/min, retention time of 24 h and at a temperature of 30 °C. Meanwhile, the highest amount of carbon dioxide (1.68 mmol CO 2 /g glucose) was obtained at a glucose concentration of 10 g/L, flow rate of 0.7 mL/min, hydraulic retention time of 24 h and at a temperature of 30 °C. The hydrogen and carbon dioxide production were affected by glucose concentration, hydraulic retention time (HRT) and fermentation time. This study showed that the ICR was a very efficient method for the production of hydrogen and carbon dioxide gases. [ABSTRACT FROM AUTHOR]

Introduction: Yellow fever (YF) is a vector-borne disease transmitted to humans by infected Aedes mosquitoes, while hepatitis E virus (HEV) is a waterborne disease that is transmitted through the fecal-oral route. Both diseases have very close clinical presentation, namely fever, jaundice, malaise, and dark urine; they differ in severity and outcome. Methodology: In this cross-sectional, laboratory-based study, an attempt was made to measure the correlation of concomitant YF and HEV infection in Darfur States during the previous YF outbreak in 2012. Results: Results found concomitant outbreaks of YF and HEV at the same time with very weak statistical correlation between the two infections during the outbreak period, with Cramer's V correlation 0.05 and insignificant p value of 0.86. Conclusions: This correlation indicates that clinicians and care providers in tropical areas have to deal with clinical case definitions used for disease surveillance very carefully since prevalence of HEV infection is relatively common and this increases the possibility of misclassification and missing YF cases, particularly initial index cases, in a season or outbreak. [ABSTRACT FROM AUTHOR]