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The motivation of this research is to study the effect of suction process on a growing gas bubble and concentration distribution around this bubble in tissues of divers who surface too quickly. The effect of bubble motion is also considered. The method of combined variables is used to solve the problem by combining the radial and time variables into one variable by using a suitable similarity transformation that enables to divide the diffusion equation into two ODEs, the first concerns to concentration distribution and the other concerns to the bubble radius evolution. The resultant formulae are valid for both growth stages whenever the ambient pressure is variable at ascending of the diver, or constant as the diving stops or at sea-level. The effects of physical parameters are discussed when applying suction process and show that the dominant parameter is the initial void fraction. The research findings reveal the role of suction process to activate the systemic blood circulation and delay the growth of gas bubbles in the tissues and reduce the incidence of decompression illness (DCI). This research also provides evidence and agrees with the previous experimental studies to support the use of suction therapy to reduce the DCI harmful effects.

This study tests binary and ternary n-pentanol, ethanol, and petrol blends to increase spark-ignition (SI) engine performance and minimize CO and HC emissions. To improve brake thermal efficiency (BTE) and reduce emissions, adding ethanol into gasoline is one of the practices used in Automobiles. But the literature reported some performance limitations and problems with adding a high ethanol concentration to gasoline as phase separation problem occurs in fuel tank due to the hygroscopic nature of ethanol, a higher ethanol concentration may corrode some parts of the fuel supply system. Ethanol has a lower calorific value than gasoline, so a higher ethanol concentration in blends beyond a specific limit reduces BTE. N-pentanol as a fuel additive in gasoline can better solve these problems due to its high caloric value compared to ethanol. Also, when n-pentanol is mixed with gasoline and exposed to moisture, it does not separate in stages as in the ethanol case. Accordingly, this research aims to evaluate n-pentanol's viability as a fuel additive in petrol and ethanol-gasoline blends at different compression ratios. The experiments were carried out on a single-cylinder, four-stroke spark-ignition engine running at a constant speed. Different blends of n-pentanol with gasoline and ethanol were tested, and results were compared against gasoline and E10 (the optimal blend of ethanol-gasoline, 10/90 v/v %). Various parameters were examined, including BTE, brake-specific fuel consumption (BSFC), and different exhaust pollutants. The effects of compression ratio values on these parameters were also recorded. The 1.5 vol% pentanol with E10 (E10P1.5) mix has the best overall characteristics, including low BSFC, high BTE, and low CO and HC emissions compared to petrol and E10 fuels. E10P1.5 shows a maximum enhancement in BTE, low BSFC, CO reduction, and HC reduction by 23.79%, 19.80%, 37.79%, and 19.46%, respectively, over gasoline. Compared to E10, the improvement is 3.64% for BTE, 4.59% for BSFC, 8.88% for CO emission reduction, and 4.13% for HC emission reduction.

Recent studies suggest that concrete creep may be further exacerbated by climate change. However, up to now this effect has not been quantified in literature. The current study addresses this gap and presents a probabilistic approach for quantitatively assessing this effect. For this purpose, five different stochastic creep models (i.e. Model Code 1999, Model Code 2010, B3, B4, and B4s models) are used under considerations of the historical and future climatic conditions in Sweden to assess the long-term creep coefficient and the subsequent stress redistribution of an axially loaded column. While some creep models show similar percentage increases in the long-term creep coefficient in all Swedish counties, other creep models show higher percentage increase values for northern than for southern counties. The highest increase in the end-of-century creep coefficient is found using models B4 and B4s (e.g. over 40% increase is possible for northernmost Sweden, i.e. Norrbotten county, under RCP8.5). Furthermore, the current article also shows that the end-of-century creep coefficient is more sensitive to uncertainties not related to the climate (i.e. parameter and creep modelling uncertainties) than to climate uncertainty.

Flying over the open sea is energetically costly for terrestrial birds. Despite this, over-water journeys of many birds, sometimes hundreds of kilometres long, are uncovered by bio-logging technology. To understand how these birds afford their flights over the open sea, we investigated the role of atmospheric conditions, specifically wind and uplift, in subsidizing over-water flight at a global scale. We first established that ΔT, the temperature difference between sea surface and air, is a meaningful proxy for uplift over water. Using this proxy, we showed that the spatio-temporal patterns of sea-crossing in terrestrial migratory birds are associated with favourable uplift conditions. We then analysed route selection over the open sea for five facultative soaring species, representative of all major migratory flyways. The birds maximized wind support when selecting their sea-crossing routes and selected greater uplift when suitable wind support was available. They also preferred routes with low long-term uncertainty in wind conditions. Our findings suggest that, in addition to wind, uplift may play a key role in the energy seascape for bird migration that in turn determines strategies and associated costs for birds crossing ecological barriers such as the open sea.

The main target of this research work is to model the output performance of adsorption water desalination system (AWDS) in terms of switching and cycle time using artificial intelligence. The output performance of the ADC system is expressed by the specific daily water production (SDWP), the coefficient of performance (COP), and specific cooling power (SCP). A robust Adaptive Network-based Fuzzy Inference System (ANFIS) model of SDWP, COP, and SCP was built using the measured data. To demonstrate the superiority of the suggested ANFIS model, the model results were compared with those achieved by Analysis of Variance (ANOVA) based on the maximum coefficient of determination and minimum error between measured and estimated data in addition to the mean square error (MSE). Applying ANOVA, the average coefficient-of-determination values were 0.8872 and 0.8223, respectively, for training and testing. These values are increased to 1.0 and 0.9673, respectively, for training and testing thanks to ANFIS based modeling. In addition, ANFIS modelling decreased the RMSE value of all datasets by 83% compared with ANOVA. In sum, the main findings confirmed the superiority of ANFIS modeling of the output performance of adsorption water desalination system compared with ANOVA.

This paper proposes the use of modified biochar, derived from Sawdust (SD) biomass using sonication (SSDB) and Ozonation (OSDB) processes, as an additive for biogas production from green algae Cheatomorpha linum (C. linum) either individually or co-digested with natural diet for rotifer culture (S. parkel). Brunauer-Emmett-Teller (BET), Fourier-Transform Infrared (FTIR), thermal-gravimetric (TGA), and X-ray diffraction (XRD) analyses were used to characterize the generated biochar. Ultrasound (US) specific energy, dose, intensity and dissolved ozone (O3) concentration were also calculated. FTIR analyses proved the capability of US and ozonation treatment of biochar to enhance the biogas production process. The kinetic model proposed fits successfully with the data of the experimental work and the modified Gompertz models that had the maximum R2 value of 0.993 for 150 mg/L of OSDB. The results of this work confirmed the significant impact of US and ozonation processes on the use of biochar as an additive in biogas production. The highest biogas outputs 1059 mL/g VS and 1054 mL/g VS) were achieved when 50 mg of SSDB and 150 mg of OSDB were added to C. linum co-digested with S. parkle.