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The present work explained the effect of brass slag reinforcement on the microstructural, mechanical and wear characteristics of Al-Si alloy (LM30) based composite. Composite with the various size range of brass slag reinforcement (fine; 0–100 µm, medium; 100–200 µm and coarse; 200–300 µm) with different concentrations (5, 10, and 15 wt.%) were prepared through stir casting route. Optical micrographs revealed that the brass slag particles are uniformly distributed in the alloy matrix. Furthermore, the experimental density of the composite samples is higher, compared to that of LM30 alloy. As a result, the hyper eutectic LM30 Al-Si alloy shows a remarkable improvement of almost 71% in hardness compared to the 15BF composite, which comprises 15 wt% of fine particle reinforcement. Furthermore, it is observed that the 15 wt.% fine particle reinforced composite specimen exhibits increased yield strength, ultimate tensile strength (UTS), and toughness, with improvements of 45%, 34%, and 76% respectively, in comparison to the base metal. In the SEM investigation of the cracked surface of composites reinforced with brass slag, the failure mode of these composites is determined to be cohesive rupture. Examining the influence of brass slag particles on wear resistance, it is found that the 15BF shows the best wear results. The wear performance of the composites remains close to that of cast iron. This analysis also reveals the formation of a tribo layer and Mechanical mixed layer (MML). [ABSTRACT FROM AUTHOR]

In this research, k-means, agglomerative hierarchical clustering and regression analysis have been applied in hydrological real time series in the form of patterns and models, which gives the fruitful results of data analysis, pattern discovery and forecasting of hydrological runoff of the catchment. The present study compares with the actual field data, predicted value and validation of statistical yields obtained from cluster analysis, regression analysis with ARIMA model. The seasonal autoregressive integrated moving average (SARIMA) and autoregressive integrated moving average (ARIMA) models is investigated for monthly runoff forecasting. The different parameters have been analyzed for the validation of results with casual effects. The comparison of model results obtained by K-means & AHC have very close similarities. Result of models is compared with casual effects in the same scenario and it is found that the developed model is more suitable for the runoff forecasting. The average value of R2 determined is 0.92 for eight ARIMA models. This shows more accuracy of developed ARIMA model under these processes. The developed rainfall runoff models are highly useful for water resources planning and development. [ABSTRACT FROM AUTHOR]

In this paper, we choose a simple analytical method based on scalar wave approximation to study the modal behaviour of an unconventional doubly clad optical waveguide having a cross section of the shape of a lemniscate. We take the appropriate orthogonal coordinates for the proposed structure and impose the boundary conditions under the weak guidance approximation to get the modal eigen value equation. Using this equation we obtain numerical results in the form of dispersion curves and cutoff frequencies. An attempt has been made to estimate how the modal behaviour changes when a single cladded waveguide having a lemniscates of Bernoulli type core cross-section is changed to a waveguide having double cladded shape of a lemniscate. It is noted that the double cladded waveguide provides an additional degree of freedom to control the cutoff frequencies on our choice. [ABSTRACT FROM AUTHOR]

Effect of different concentrations of naturally occurring admixture in the form of fine powder of black gram pulse (BGP) on the hydration of Portland cement was studied by isothermal calorimetry and 57Fe Mössbauer spectroscopy. The spectra were recorded for anhydrous cement and the hydration products at room temperature and 77 K. In the presence of BGP, the spectra showed superparamagnetic doublets at room temperature and the sextet at 77 K, due to the presence of fine particles of iron containing component. Mössbauer studies of hydration products confirmed the formation of nanosize hydration products containing Fe3 + . The isomer shift ( δ) and the quadrupole splitting (Δ E Q) values of C4AF in the cement confirmed iron in an octahedral and tetrahedral environment with +3 oxidation state. The high value of quadrupole splitting showed the high asymmetry of the electron environment around the iron atom. The overall mechanism of the hydration of cement in presence of BGP is discussed. [ABSTRACT FROM AUTHOR]

A procedure for the complete chemical analysis of magnesium or sodium diuranate (yellow cake) sample is reported. Uranium is determined gravimetrically after peroxide precipitation. Optimum parameters, such as pH, quantity of hydrogen peroxide, volume of sample, temperature and complexing agent for quantitave precipitation of uranium, and effective separation of other elements were studied. Aluminum, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn were determined by flame atomic absorption spectrometer and B, Mo, SO4, REEs and Y by inductively coupled plasma atomic emission spectrometer in the filtrates of hydroxide and peroxide precipitation separation. The proposed method is accurate and the precision is characterized by an RSD of ~0.2% for U; 2 to 6% for Mg, Na, K, Ca, Fe, SiO2, Al, Cd, Co, Cr, Fe, Mn, Ni, Pb, and Zn and 3 to7% for REEs, Y, Mo and B [ABSTRACT FROM AUTHOR]

A theoretical model has been developed for predicting the flow behavior of dual-phase steels containing retained austenite. A good agreement between theoretical predictions and experimental values is obtained by optimizing the value of load-transfer factor and by using an additional term considered to account for the geometrically required dislocations around the hard particles. [ABSTRACT FROM AUTHOR]