Processing of Orange Peel Biomass waste of Juice Industries and Valorization to Smart Acoustic Material

Non-destructive technique like ultrasonication has played crucial role in fabrication of effective graded acoustic material using carbon rich organic waste material. The peculiar structural configuration inside the fibrous material like orange peel have attract the researcher to create special interest in designing of some building acoustic material as well as many technological products. The noise reduction property of orange peel fibres of different particle size has been improved considerably after ultrasonically mercerization of NaOH.High penetrating and dispersive property of ultrasonic wave to assemble and regrouping among the fibrous material are quite remarkable for enhancing noise attenuation inside the composite. Scanning Electron Microscopy (SEM), Energy Dispersive Spectra(EDS), Fourier Transform Infra-Red(FTIR) and X-Ray Diffraction(XRD) analysis of both untreated and treated orange peel fibre of different particle size indicate the deformation in cellulose as well as anti cellulose with the aid of ultrasonicationpermits the composites to be a suitable acoustic material. The result confirm that ultrasonic treated composite has potential to absorb 88.6% of sound which makes it a class- B noiseabsorber with peripheral mechanism within the composite.

Preparation of polyethyleneimine modification of flower molybdenum disulfide composite(PEI/MoS2) adsorbent and studying it enriched and reduction property for hexavalent chromium from wastewater

In this study, flower molybdenum disulfide (MoS2) was surface-modified with polyethyleneimine(PEI) to prepare PEI/MoS2 composite adsorbents for Cr(VI) enrichment in aqueous solution. The physicochemical properties of PEI/MoS2 were characterized by SEM, TEM, XRD, FTIR, BET and XPS methods. The influences of PEI loading, solution pH, contact time, adsorption temperature, and initial Cr(VI) ion concentration on the adsorption performance of PEI/MoS2 for Cr(VI) were investigated. Under the optimal conditions, and the initial Cr(VI) ion concentration is 50 mg L− 1, the adsorption capacity of PEI/MoS2 is 120.7 mg g− 1. The adsorption rate is fast, equilibrium time is 6 h. Competitive adsorption studies of the Cr(VI), Co(II), Zn(II) and Cd(II) quaternion system were also investigated, the results indicated that selectively adsorbed amount of Cr(VI) on PEI/MoS2 is significantly higher than that of Co(II), Zn(II) and Cd(II) ions. The adsorption process was spontaneous and conformed to Freundlich isotherm and pseudo-second kinetic model. The consecutive adsorption-desorption experiments indicated that the PEI/MoS2 has excellent reusability.

DOA Estimation Using Fourth-Order Cumulants in Nested Arrays with Structured Imperfections

Recently developed super nested array families have drawn much attention owing to their merits on keeping the benefits of the standard nested arrays while further mitigating coupling in dense subarray portions. In this communication, a new mutual coupling model for nested arrays is constructed. Analyzing the structure of the newly formed mutual coupling matrix, a transformation of the distorted steering vector to separate angular information from the mutual coupling coefficients is revealed. By this property, direction of arrival (DOA) estimates can be determined via a grid search for the minimum of a determinant function of DOA, which is induced by the rank reduction property. We also extend the robust DOA estimation method to accommodate the unknown mutual coupling and gain-phase mismatches in the nested array. Compared with the schemes of super nested array families on reducing the mutual coupling effects, the solutions presented in this paper has two advantages: (a) It is applicable to the standard nested arrays without rearranging the configuration to increase the inter-element spacing, alleviating the cross talk in dense uniform linear arrays (ULAs) as well as gain-phase errors in sparse ULA parts; (b) Perturbations in nested arrays are estimated in colored noise, which is significant but rarely discussed before. Simulations results corroborate the superiority of the proposed methods using fourth-order cumulants.