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Emerging pollutants and a large volume of unused dyes from the textile industry have been contaminating water bodies. This work introduces a scalable approach to purifying water by the adsorption of Acid green 25 (AG), Crystal Violet (CV), and Sulfamethoxazole (SMA) from an aqueous solution by graphene oxide (GO) doped modified silica aerogel (GO-SA) with supercritical fluid deposition (SFD) method. Characterization of GO-SA using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), high-resolution scanning electron microscopy (HR-SEM), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) adsorption isotherms revealed the improvement in the adsorbent surface area, and its textural properties. The high removal percentages observed in most of the experimental runs provide evidence of the excellent performance of the adsorbent towards the anionic and cationic dyes along with the antibiotic. The adsorption isotherm and kinetics showed that the Langmuir isotherm and pseudo-second-order kinetic models could explain adsorption. The adsorbent holds a higher adsorption capacity for SMA (67.07 mg g−1) than for CV (41.46 mg g−1) and AG (20.56 mg g−1) due to the higher hydrophobicity that interacts with the hydrophobic adsorbent. The GO-SA successfully removed AG, CV, and SMA with removal percentages of 98.23%, 98.71%, and 94.46%, respectively. The parameters were optimized using Central Composite Design (RSM-CCD). The prepared aerogel showed excellent reusability with a removal efficiency of > 85% even after 5 cycles. This study shows the potential of GO-SA adsorbent in textile and other wastewater purification. [ABSTRACT FROM AUTHOR]

Emerging pollutants and a large volume of unused dyes from the textile industry have been contaminating water bodies. This work introduces a scalable approach to purifying water by the adsorption of Acid green 25 (AG), Crystal Violet (CV), and Sulfamethoxazole (SMA) from an aqueous solution by graphene oxide (GO) doped modified silica aerogel (GO-SA) with supercritical fluid deposition (SFD) method. Characterization of GO-SA using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), high-resolution scanning electron microscopy (HR-SEM), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) adsorption isotherms revealed the improvement in the adsorbent surface area, and its textural properties. The high removal percentages observed in most of the experimental runs provide evidence of the excellent performance of the adsorbent towards the anionic and cationic dyes along with the antibiotic. The adsorption isotherm and kinetics showed that the Langmuir isotherm and pseudo-second-order kinetic models could explain adsorption. The adsorbent holds a higher adsorption capacity for SMA (67.07 mg g−1) than for CV (41.46 mg g−1) and AG (20.56 mg g−1) due to the higher hydrophobicity that interacts with the hydrophobic adsorbent. The GO-SA successfully removed AG, CV, and SMA with removal percentages of 98.23%, 98.71%, and 94.46%, respectively. The parameters were optimized using Central Composite Design (RSM-CCD). The prepared aerogel showed excellent reusability with a removal efficiency of > 85% even after 5 cycles. This study shows the potential of GO-SA adsorbent in textile and other wastewater purification. [ABSTRACT FROM AUTHOR]

Fourier series are of great importance in both theoretical and applied mathematics. This paper will focus on the Fourier series of the complex exponentials of the many possible methods of estimating complex valued functions, Fourier series are especially attractive because uniform convergence of the Fourier series (as more terms are added) is guaranteed for continuous, bounded functions. After studying this paper we will learn about how Fourier transforms is useful in many physical applications, such as partial differential equations and heat transfer equations. one can solve many important problems of physics with very simple way. [ABSTRACT FROM AUTHOR]

This paper deals with development of an n-bit binary to decimal conversion, decimal to n bit binary conversion and decimal to IEEE-754 conversion for floating point arithmetic logic unit (FPALU) using VHDL. Normally most of the industries now a days are using either 4-bit conversion of ALU or 8-bit conversions of ALU, so we have generalized this, thus we need not to worry about the bit size of conversion of ALU. It has solved all the problems of 4-bit, 8-bit, 16-bit conversions of ALU's and so on. Hence, we have utilized VHSIC Hardware Description Language and Xilinx in accomplishing this task of development of conversions processes of ALU. [ABSTRACT FROM AUTHOR]

This study presents a sustainable HyPurif process for managing and recycling industrial water effluent, utilizing gas hydrate-based technology to purify complex effluent. This work purifies two effluents: one from a wastewater treatment plant (WWTP) and the other from a spent caustic treatment plant (SCTP). Various hydrate formers, including propane, HFC134a, and cyclopentane (6 mol %), were selected, as they typically form hydrates closer to ambient conditions. Hydrate formation experiments with effluent water were performed at 278.30 K using pure propane and HFC134a gas. Based on the kinetics of hydrate growth, the study was extended to a mixture (50:50%) of propane and HFC134a, operating at a pressure of 0.6 MPa. The mixture of propane and HFC134a has shown the desired result of forming the hydrate in the gas phase and having high separation efficiency. The results showed that the formation and dissociation of hydrates resulted in a separation efficiency of 80–95%. For instance, in the purified water, the biological oxygen demand (BOD) decreased from 2097 mg/L in the effluent sample to 220 mg/L in purified water (purification efficiency of 90.5%). The chemical oxygen demand (COD) decreased from 3100 mg/L in the effluent sample to 503 mg/L in purified water (purification efficiency of 84%). Total dissolved solids (TDS) were reduced from 89,632 mg/L in the effluent water to 14,698 mg/L in purified water (purification efficiency of 84%). Total suspended solids (TSS) were reduced from 35 mg/L in the effluent water to 3.5 mg/L in purified water (purification efficiency of 90%). However, the purification efficiency for free ammonia and residual chlorine was lower. The concentration of free ammonia decreased from 7 mg/L in the effluent sample to 1.89 mg/L in the purified water (purification efficiency of 73%), and residual chlorine reduced from 0.8 mg/L in the effluent sample to 0.2 mg/L in the purified water (purification efficiency of 75%). Water recovery of ≥40% was achievable per pass, which could be increased, but at the expense of purification efficiency. To the best of our knowledge, this is the first study on the purification of such complex wastewater containing organic and inorganic compounds, heavy metals, and various minerals using the HyPurif process. [ABSTRACT FROM AUTHOR]

This paper deals with system level simulation of VHDL which is a hardware description language that is gaining increasing popularity among digital designers, as it is both a synthesis and simulation language. Secondary goals were to document the design methodology as well as state-of-the-art of the tools required for FPGA design and simulation. [ABSTRACT FROM AUTHOR]