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Effect of aluminium salts on the synthesis of AlOOH nanostructures has been successfully investigated in detail using solvothermal method, when ethanol and NaOH are solvent and pH adjusting agent, respectively. Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), and field emission scanning electron microscopy (FESEM), were used to characterize the synthesized samples. The specific surface area, pore size distribution and pore structure of the different AlOOH structures were also discussed by the N2 adsorption/desorption test. According to our experimental results, the structure characterization revealed that for synthesized AlOOH nanostructures no obvious XRD peaks arising from other phases of alumina are found indicating pure AlOOH phase of products. Furthermore, the nitrogen adsorption and desorption measurements indicated that the obtained AlOOH nanoparticles from aluminium chloride at basic condition possess a high BET surface area of approximately 90 m2/g. Resumen: El efecto de las sales de aluminio sobre la síntesis de las nanoestructuras de AlOOH ha sido analizado en detalle satisfactoriamente usando el método solvotérmico, cuando el etanol y el NaOH son el disolvente y el agente de regulación del pH, respectivamente. Para clasificar las muestras sintetizadas se utilizaron la espectroscopia infrarroja por transformada de Fourier (FTIR), difracción de rayos X por polvo (XRD) y microscopia electrónica de barrido de emisión de campo (FESEM). El área superficial específica, la distribución del tamaño del poro y la estructura de poros de las diferentes estructuras de AlOOH también se debatieron mediante la prueba de adsorción/desorción de N2. De acuerdo con nuestros resultados experimentales, la clasificación de la estructura reveló que en las nanoestructuras de AlOOH sintetizadas no se observan picos XRD evidentes derivados de otras fases de la alúmina que indican la fase pura de AlOOH de los productos. Además, las mediciones de adsorción y desorción de nitrógeno indicaron que las nanopartículas de AlOOH obtenidas a partir de cloruro de aluminio en estado básico poseen un área superficial BET elevada, de aproximadamente 90 m2/g. Keywords: AlOOH, Salts, Nanoparticle, Solvothermal, Palabras clave: AlOOH, Sales, Nanopartícula, Solvotérmico

This study proposes an adaptive interval type-2 Takagi–Sugeno–Kang (IT2 TSK) fuzzy system with a supervisory mode to control and stabilise a certain class of non-linear fractional order systems. In this study, a fractional order adaptation law is derived which adjusts the free parameters and bounds them by utilising a projection algorithm. The global Mittag–Leffler stability of the closed-loop system is proved in the sense that all the involved signals are uniformly bounded. Moreover, if the non-linear system tends to be unstable, a supervisory controller starts cooperating with the adaptive IT2 TSK fuzzy controller to guarantee the stability of the closed-loop system. In addition, a new inference mechanism for the adaptive IT2 TSK fuzzy system is introduced for which the antecedent part is chosen as a type-2 fuzzy set and the consequent parameters are represented as interval sets. According to the practical nature of the proposed inference equation, it would be applicable in online and real-time applications. Numerical simulations show the validity and effectiveness of the introduced control strategy for stabilisation and control of a general class of non-linear fractional order systems perturbed by disturbance and uncertainty.

In this paper, a direct adaptive fuzzy controller with compensation signal is presented to control and stabilize a class of fractional order systems with unknown nonlinearities. Based on a Lyapunov function candidate the global Mittag–Leffler stability is proved and a new fractional order adaptation law is derived. The adaptation law adjusts free parameters of the fuzzy controller and bounds them by utilizing a novel fractional order projection algorithm. Furthermore, due to the use of compensation term, the proposed approach does not demand suitable membership functions in the fuzzy system. In addition, the stability of the closed-loop system is guaranteed by utilizing a supervisory controller. Numerical simulations show the validity and effectiveness of the introduced scheme for various fractional order nonlinear models that perturbed by disturbance and uncertainty.

In this study, a colorimetric paper-based biosensor was developed for the highly sensitive and selective determination of phenylalanine. Reagents were immobilized onto the paper substrate to form the test paper. The phenylalanine dehydrogenase (PheDH) enzyme reacts specifically with phenylalanine in the presence of NAD+ to form NADH that reacts with MTT, which is catalyzed by the diaphorase enzyme to form the purple colored formazan. The increase of phenylalanine concentration is proportional to the color intensity and can be monitored by the color change of the dye solution. It was discovered that Au NPs interact with cationic dye (MTT) which causes the enhancement of color intensity. The colored reaction product could be either qualitatively assessed by the naked eye or quantified using a smartphone camera evaluated by the freeware Image J. This paper-based test is easy to operate, and can develop the results within 10 min. After applying the optimal conditions, the linear range for phenylalanine was found to be from 0.8 to 33 (mg/dL) with a detection limit of 0.57 (mg/dL), using the digital image method. Furthermore, analysis of phenylalanine levels in real samples was enabled as a result of the promising detection performance of the developed approach, which could be used as a screening test for PKU in newborns in situations where current approaches cannot be used.

In this study, AlOOH nanostructures were successfully synthesized using the solvothermal method at 180?C. The effects of the pH of the solution (3, 4.5, 6.5, 10 and 12.5) on the synthesized samples were investigated systematically in detail, when ethanol and NaOH were the solvent and pH-adjusting agent, respectively. Fourier transform infrared spectroscopy, X-ray powder diffraction and field emission scanning electron microscopy were used to characterize the synthesized samples. The specific surface area, pore size distribution and pore structure of different AlOOH structures at various pH levels were also discussed in terms of the N2 adsorption/desorption test. According to the experimental results, the FESEM micrographs showed that the products were nanostructures, and the AlOOH nanoparticles larger on increasing the pH from 4.5 to 12.5. The structure characterization revealed that the resulting AlOOH nanostructures were pure and had a well-defined crystalline structure with a crystal size of 9.3?20.5 nm. Furthermore, the boehmite obtained at pH 12.5 exhibited a large surface area of 131 m2 g-1 and a high total pore volume of 1.24 cm3 g-1.