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Novel nanocomposite smart hydrogel (NSH) and smart hydrogel (SH) are prepared to be used as a support for invertase. Spectrophotometric and thermal analysis methods were used for the characterization. Lower critical solution temperature values of SH and NSH were found as 32.68°C and 30.44°C, respectively. From the pH-responsive swellings performed at three different temperatures, the inflection point values of NSH were found at higher pHs compared to SH. Invertase was immobilized onto SH and NSH (SH−I and NSH−I). The optimum pH and temperature values were found. Michaelis constant and maximum reaction rate were calculated. NSH−I showed excellent thermal, operational and pH stability. [ABSTRACT FROM AUTHOR]

In this study, mathematical models of air cooled condensers with circular and elliptic cross-sections were developed and performances were evaluated with artificial neural networks. Air velocity, orientation angle and ambient temperature were used as the input to the neural network structure while heat transfer rate to the air was used as the output. The data sets were generated from high fidelity, computationally inefficient expensive three dimensional computational fluid dynamics simulations. It was observed that artificial neural network model replaces computational fluid dynamics model and based on the mathematical model with artificial neural network, elliptic condensers perform better in terms of heat transfer compared to circular ones. [ABSTRACT FROM AUTHOR]

A finite element solution has been performed in this work to solve unsteady governing equations of natural convection in a carbon nanotube–water-filled cavity with inclined heater. The temperature of ceiling and left vertical walls is lower than that of the heater while the other walls are adiabatic. The main governing parameters are nanofluid volume fraction and Rayleigh number (Ra). It is found that the heat transfer rate shows different trends based on Rayleigh number and it increases with increase in nanoparticle volume fraction. It has been estimated that average Nusselt number (Nu) is dependent onRathrough power regression models with strong positive linear correlation between ln (Nu) and ln (Ra). In particular, for the maximum time, when the solid volume fraction is varied from 0 to 0.1 the dependence between averageNuand linearRa, on a logarithmic scale, is very high. [ABSTRACT FROM AUTHOR]

In this paper, a two-dimensional (2D) numerical simulation has been performed for an unsteady magnetohydrodynamics (MHD) flow around a solid square cylinder placed in a channel. Computational simulations were done for the ranges of Reynolds and Stuart numbers of 1-250 and 0-10, respectively. Finite volume method (FVM) has been used to solve the unsteady Navier-Stokes equations. The effects of streamwise magnetic field on the flow separation and suppress of the vortex shedding are studied in detail for the above ranges. Additionally, four new empirical equations for wake length and Stuart number are suggested. Finally, a comparison is performed between the cases of with and without a channel to study the effect of channel walls. The obtained results revealed that Strouhal number decreases linearly with increasing Stuart number. Also, the flow distribution pattern changes from time-dependent pattern to steady-state by increasing Stuart number. [ABSTRACT FROM AUTHOR]

An experimental study on performance and exhaust emission of a spark-ignited engine fueled by gasoline-like fuel obtained from waste automobile tires using the prolysis process was performed in this study. Gasoline-like fuel has a higher octane number than unleaded gasoline; however, it has higher in viscosity in comparison to unleaded gasoline, which limited the use of gasoline-like fuel in neat form. Therefore, gasoline-like fuel was blended with unleaded gasoline from 0% to 100% with an increment of 10%, volumetrically. Obtained blends were then used in a spark-ignited engine. It was observed that the test engine was normally run up to blended fuel containing gasoline-like fuel of 60%. It is concluded that gasoline-like fuel can be partially substituted for the gasoline fuel up to 60% in blended form in terms of performance parameters and emissions without any engine modification. [ABSTRACT FROM PUBLISHER]

Air pollution is becoming a serious problem in many urban cities of the world and it can have a serious effect on both health and the environment. Although experimental studies have shown that alcohol fuels burn cleaner than unleaded gasoline and produce lesser emission, there is limited information regarding the comparison among the alcohol fuels as gasoline additive in spark-ignited engines. Therefore, a comparison has been performed in this experimental work on the exhaust emissions of a spark-ignited engine when operating on a blend of methanol, ethanol, orn-butanol with unleaded gasoline. Methanol, ethanol and n-butanol were added to unleaded gasoline by mass percent of 10% (denoted as M10, E10 and Bu10, respectively), and then tested in a four cylinder, four strokes spark-ignited engine. Although the experimental results show little differences in exhaust emissions between M10, E10, and Bu10, compared with Bu10, M10 and E10 have lower carbon monoxide emission and higher fuel consumption, hydrocarbon, and CO2emission. Compared with unleaded gasoline, blended fuels containing different alcohols appear to have a lower carbon monoxide and hydrocarbon emissions and a higher fuel consumption rate and CO2emissions. [ABSTRACT FROM AUTHOR]

Novel composite hydrogels, poly(acrylamide)–sepiolite (PAS), poly(acrylamide/acrylic acid)–sepiolite (PAAS), and poly(acrylamide/itaconic acid)–sepiolite (PAIS) were prepared and used for the immobilization of invertase. The parameters of equilibrium swelling, diffusional exponent, and diffusion coefficient of these hydrogels were calculated from swelling experiments. Invertase was immobilized onto PAS, PAAS, and PAIS and immobilized invertases (PASI, PAASI, and PAISI) were prepared. Optimum pH values for free invertase, PASI, PAASI, and PAISI are found to be 5, 5.5, 4.5, and 6, respectively, and the optimum temperatures were 30, 50, 50, and 35 °C for free invertase PASI, PAASI, and PAISI. It was found that Km values of free invertase, PASI, PAASI, and PAISI were 11.3, 41.0, 94.5, and 56.0 mM, respectively. Vmax values were 2 μmol/min for free invertase, 8.10 μmol/min for PASI, 1.30 μmol/min for PAASI, and 0.42 μmol/min for PAISI, respectively. The invertase immobilized hydrogels showed excellent, temperature, storage, and operational stability. [ABSTRACT FROM AUTHOR]

Acrylamide/sodium acrylate (AAm/SA) copolymers, prepared by using various crosslinkers, were used in experiments on swelling, diffusion, immobilization of yeast cells (Saccharomyces cerevisiae) and production of ethyl alcohol. AAm/SA hydrogels were used for swelling and diffusion studies in the nutrient medium of the cells. The parameters of equilibrium swelling, maximum swelling, initial swelling rate, diffusional exponent, network constant and diffusion coefficient of the hydrogel/penetrant systems were calculated and evaluated. Yeast cells were immobilized onto the hydrogels by adsorption method during multiplication and ethyl alcohol production of the hydrogels was investigated. Swelling of AAm increased with the addition of SA and ethyl alcohol production increased with increasing SA in the hydrogels. The best system for immobilization is found to be AAm/SA hydrogels containing N,N′-methylenebisacrylamide as crosslinker. [Copyright &y& Elsevier]

Radiation crosslinked acrylamide/maleic acid (AAm/MA) copolymers were prepared by γ-irradiation. They were used in experiments on swelling, diffusion, and immobilization of yeast cells (Saccharomyces cerevisiae) for the production of ethyl alcohol. AAm/MA hydrogels containing different amount of MA, irradiated at different doses, were used for swelling and diffusion studies. The parameters of swelling, diffusional exponents, network constants, diffusion coefficients and percent porosity of the hydrogel/penetrant systems were calculated and evaluated. Yeast cells were immobilized on to the hydrogels by adsorption during multiplication, and ethyl alcohol production by the hydrogels was investigated. Swelling of AAm/MA increased with increase in MA content. Ethyl alcohol production also increased with increasing MA in the hydrogels but decreased with an increase of irradiation dose. [Copyright &y& Elsevier]

Despite advancements in diagnostic modalities, delineating the etiology of fever of unknown origin (FUO) remains a significant challenge for clinicians. Notably, cases with hematological malignancies often have a poor prognosis due to delayed diagnosis. This study investigated the potential of readily obtainable laboratory markers to differentiate hematological causes from other etiologies during the early stages of FUO. A retrospective analysis was conducted on the medical records of 100 patients who fulfilled the modified FUO criteria between January 2010 and April 2023. Hematological etiologies were identified in 26 of the 100 patients. Peripheral blood neutrophil, lymphocyte, platelet counts, and the systemic immune inflammation (SII) index, were significantly lower in the hematological group compared to the non-hematological group. Conversely, serum ferritin levels were demonstrably higher in the hematological group. ROC analysis identified a neutrophil-to-ferritin ratio (NFR) cutoff value of < 8.53 as optimal for predicting hematological etiology. Subsequent multivariate analysis demonstrated that the NFR was the sole independent predictor of hematological etiology (p = 0.013).This study proposes a novel approach for early diagnosis of a potentially life-threatening subset of FUO patients. The NFR presents as an inexpensive and readily available marker for predicting hematological etiology in FUO cases., (© 2024. The Author(s).)

Objective: This study examined the influence of socio-economic and demographic variables, the frequency of travel to Turkey and years of living in Sydney on the life satisfaction of older Turkish people., Methods: This study was conducted with 110 participants of 60 years of age or older, at the New South Wales Turkish Welfare Association in Sydney, Australia. The surveys were administered face-to-face at a date and time these participants went to the Association. The dependent variable of the study was the Life Satisfaction Scale. The study data were analysed using hierarchical regression analysis, and the three sets of regression models were run for each sex., Results: The research found that in addition to sociodemographic factors, frequency of travel to Turkey, particularly for older women, and their years of living in Sydney had negative effects on life satisfaction. The study results indicate that the frequency of both the male and female participants' visits to Turkey had a strong negative influence on their life satisfaction. Life satisfaction decreased as the frequency of the participants' visits to Turkey and years of living in Sydney increased., Conclusion: These findings support the current literature that shows the effects of the frequency of travel to Turkey and years of living in Sydney, which were considered to influence relationships with social networks, on life satisfaction, and indicates the necessity for a more detailed examination of social network relationships., (© 2017 AJA Inc.)