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Hybrid composite refers to as an attractive structural material due to its ability to provide a better combination of properties with respect to single-particle-containing composite. Composites wer...

The present research focuses on the effects of aluminum (Al) and silicon carbide (SiC) hybridization on mechanical and morphological properties of Al and SiC particles reinforced hybrid epoxy composites. Composites were prepared by hand lay-up technique at five levels of reinforcement loading (10, 20, 30, 40, and 50 wt%). Aluminum powder and silicon carbide particles were utilized as reinforcement at a ratio of (1:1) during composite preparation. Microstructural analysis using a scanning electronic microscope and optical microscope was performed to observe the adhesiveness between the matrix and reinforcement. For mechanical characterization, tensile, flexural, impact, and hardness tests were performed. Tensile and flexural strength decreased, while Young’s modulus, flexural modulus, impact strength, and hardness increased with increase in aluminum and silicon carbide particle loading. Based on the particle loading, 50 wt% of particle-reinforced composite had the best set of mechanical properties among all prepared composites.

This research work designates for the assessment of effluent variables after dyeing of 100% cotton fabric with synthesized reactive dyes namely, Reactive Blue 19 (mono functional), Reactive Black 5 (homo bi-functional), and Reactive Red 195 and Reactive Yellow 145 (hetero bi-functional) dyes under four individual dye concentration 0.5%, 2.5%, 4.5% and 6.5%, respectively. Textile effluents were collected from two stages, after dyeing without and with additional fixing treatment mainly for the determination of DO, BOD, pH and minimization of COD values. Result exposed an overall COD reduction of about 95% for the effluent generated from both stages with all dye concentrations. Here most DO, BOD, pH values were obtained from textile effluents after dyeing stage whereas comparatively least values were revealed for the effluents collected after dyeing–fixing stage; and minimized COD values were found for both stages. In addition to this, the effluents containing mono functional Reactive Black 5 and hetero bi-functional Reactive Yellow 145 dyes shows the most and the least environmental parameters, respectively for all dye concentrations.

PurposeThis paper aims to examine the loss of tenacity and colorfastness properties of bleached and modified (acrylonitrile, AN and methacrylonitrile, MAN) jute fibres dyed with Reactive Orange 14 and Basic Violet 14.Design/methodology/approachJute fibres dyed with Reactive Orange 14 and Basic Violet 14 were studied as a function of exposure to sunlight in air, washing with soap solution and spotting with acids and alkalis.FindingsDye absorption of Basic Violet 14 was higher compared to Reactive Orange 14 at optimum dyeing conditions. Optimum dye uptake of Reactive Orange 14 required relatively severe conditions compared to that of Basic Violet 14. Whereas, Reactive Orange 14 showed overall good colorfastness to sunlight and moderate in washing compared to Basic Violet 14. All the bleached and modified fibres showed good colorfastness to weak acids and alkalis regardless of Reactive Orange 14 and Basic Violet 14 dyes. The loss in tenacity was higher in the case of non-modified fibres, and among the modified fibres, Basic Violet 14 showed the lowest loss in tenacity in the exposure to sunlight.Originality/valueMany studies have been devoted to improve the substantivity of cellulosic fibre for reactive dyes. A few efforts were made to improve the light fastness. In this work, investigation will be made on a comparative study of loss of tenacity and colorfastness properties of bleached and modified (AN and MAN) jute fibres dyed with both Reactive Orange 14 and Basic Violet 14 on exposure to sunlight, washing and acid and alkali spotting. Optimum dyeing conditions will also be investigated for economic dyeing.

A new and sensitive spectrofluorimetric method has been proposed to determine trace amount of adenosine disodium triphosphate (ATP). The method is based on the fluorimetric interaction between gatifloxacin (GFLX)-aluminium (III) (Al(3+) ) complex and ATP and studied using UV-visible and fluorescence spectroscopy. Weak luminescence spectra of Al(3+) were enhanced after complexation with GFLX at 423 nm upon excitation at 272 nm due to energy transfer from the ligand to the Al(3+) ion. It was observed that the FL emission spectrum of GFLX-Al(3+) was enhanced significantly by the addition of ATP. Under the optimal conditions, the enhancement of FL intensity at 423 nm was responded linearly with the concentration of ATP in the range 1.3 × 10(-10) - 1.0 × 10(-8) mol L(-1) with correlation coefficient (r) of 0.9981. The limit of detection (LOD) was found to be 1.1 × 10(-11) mol L(-1) for ATP with the standard deviation (RSD) of 1.21% for five repeated measurement of 2.3 × 10(-8) mol L(-1) ATP. The presented method is simple, sensitive, free from coexisting interferents and can be applied successfully to determine ATP in the real samples.

In this work, mechanical milling of magnesium with SiC particles with variation of parameters, such as ball-to-powder ratio, milling speed, milling time, and process controlling agent (PCA), is reported. Milling was also conducted without using PCA to explore its role on the mechanical milling process. Milling was performed in a planetary ball mill. The results show that a uniform distribution of the reinforcement, good particle yield, and particle size reduction can be achieved by controlling the parameters. The milling powders were compacted using the underwater shock wave generated by the detonation of an explosive. The samples were characterized by XRD, scanning electron microscopy, and microhardness testing. Microstructural characterization revealed a well flown magnesium matrix enveloping reasonably well dispersed SiC particles. The results of microhardness testing reveal an increase in the hardness of the composite.

An improved multivoltine variety of Rajshahi silk fabric is used as material for investigation. This fabric is degummed to remove sericin, as sericin is soluble in hot water and highly responsible for the fading of dyed silk after washing. Rajshahi silk fabric is dyed with Reactive Brown 10 and Direct Orange 31 dyes. The color of the silk fabric becomes even and bright when it is dyed with 2.0% Reactive Brown 10 and 2.5% Direct Orange 31 after 50-60 minutes at 80-100°C. To achieve fast color, the silk fabric is treated with six modifying conditions prior to dyeing and among them, comparatively better modifying conditions are selected on the basis of color fastness upon exposure to sunlight in air and wash fastness in a soap solution. The modified Rajshahi silk fabric with 30% CH3COOH and 20% tannic acid together show better dyeing properties than modifications with other conditions and unmodified silk fabric. Direct Orange 31 shows better colorfastness than Reactive Brown 10 after exposure to sunlight in air and also after washing with a soap solution.

The shock consolidation of magnesium (Mg)/silicon carbide (SiC) composites using axisymmetric explosive fabrication setup is reported. Pure Mg and SiC powders are consolidated in a three-layered cylindrical assembly with the energy being derived from a high-detonation velocity explosive. The pressure of underwater shock wave is experimentally measured and simulated using AUTODYN 2D. Microstructural characterization of the samples revealed a well-flown Mg matrix enveloping near homogeneous SiC particles. Occasional clustering of SiC particles and interparticle melting is evidenced. Results of microhardness revealed that the presence of SiC particulates led to a substantial increase in the hardness of the composite. Fractography results indicate the lack of formation of ductile dimples, which is attributed to the presence of discontinuous SiC particles. The strengthening mechanism, the absence of reaction products, the structure–property correlation of the shock consolidated composite are discussed.

A new and sensitive spectrofluorimetric method has been proposed to determine trace amount of adenosine disodium triphosphate (ATP). The method is based on the fluorimetric interaction between gatifloxacin (GFLX)-aluminium (III) (Al(3+) ) complex and ATP and studied using UV-visible and fluorescence spectroscopy. Weak luminescence spectra of Al(3+) were enhanced after complexation with GFLX at 423 nm upon excitation at 272 nm due to energy transfer from the ligand to the Al(3+) ion. It was observed that the FL emission spectrum of GFLX-Al(3+) was enhanced significantly by the addition of ATP. Under the optimal conditions, the enhancement of FL intensity at 423 nm was responded linearly with the concentration of ATP in the range 1.3 × 10(-10) - 1.0 × 10(-8) mol L(-1) with correlation coefficient (r) of 0.9981. The limit of detection (LOD) was found to be 1.1 × 10(-11) mol L(-1) for ATP with the standard deviation (RSD) of 1.21% for five repeated measurement of 2.3 × 10(-8) mol L(-1) ATP. The presented method is simple, sensitive, free from coexisting interferents and can be applied successfully to determine ATP in the real samples.