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The present paper reports the study on manganese-silicon steel cast through a clean liquid metallurgical route; in order to assess the tribological behaviour of the steel, the solidified ingots were subjected to heat treatments, such as annealing, ice water quenching, followed by ageing the quenched steel at 550 °C, 600 °C, 650 °C and 700 °C for two hours. For evaluation of hardness, tensile strength and sliding wear properties; the desired samples were prepared as per usual standards. The best combination of the ultimate tensile strength (476.83 MPa), microhardness (252.23 HV), and mean specific wear rate of 2.269E-05 mm3/N-m is achieved for alloy 1 after ageing at 650 °C. Fractography of broken tensile samples and microstructural characterization of worn-out surfaces are carried out by scanning electron microscopy (SEM); these have aided in the determination of the dominant wear mechanism and mode of fracture during tensile loading. The mixed-mode fracture is predominantly observed in most of the fractured surfaces, and the dominant wear mechanism is found to be adhesive wear. Moreover, X-ray diffraction (XRD) analysis has shown the presence of phases like austenite, α' martensite, ɛ martensite, along with AlNi3, Ni2Al3, and M2C precipitates. [ABSTRACT FROM AUTHOR]

This paper reviews the basic understanding of Mg-based thermoelectric materials and various approaches for increasing their thermoelectric efficiency. Recent developments in terms of enhancement of electrical properties and reduction of thermal conductivity of Mg2(Si,Sn) materials through experimental investigation and applying modeling approaches are discussed in detail. Further, the role of deformation and heat treatment analysis for achieving optimum thermoelectric properties in this material system and its prospects for further developments as a commercially viable solution is enumerated. The solid solutions of Mg2X (X = Si,Ge,Sn) thermoelectric material are identified as the most favorable alloy class of thermoelectric materials for application in the intermediate temperature range (400–800 K). The reason for Mg2X alloys becoming the preferred choice over others is because they are cheap, abundant and non-toxic. Improving the efficiency of magnesium-based thermoelectric materials through various advancements in experimental methods has appeared as a matter of great commercial importance. However, theoretical understanding of the phenomenological issues confronting the attainment of desirably high thermoelectric properties has not been widely touched upon; this leads to enormous opportunities for optimizing the figure of merit of thermoelectric materials through numerical modeling and simulation techniques. Also, deforming the alloys has been proved to be favorable for the thermoelectric performance of the material; a lot of work has been carried out for other classes of thermoelectric materials, but there is a disparity in interpreting the deformation behavior of Mg2Si1−xSnx alloys and its impact on thermoelectric properties due to lack of adequate efforts to conduct systematic investigations in the area of concern. [ABSTRACT FROM AUTHOR]

Resistance to early blight in the tomato was assessed by examining various parameters of the progress of the disease. Artificial inoculation and the scoring technique were standardized. Test plants were inoculated with 125 cfu/ml of a 12-day-old culture of a pathogenic isolate of Alternaria solani. Screening under artificial conditions was more informative than that under natural epidemic conditions. Tomato cultivars CLN-2071-C, CLN-2070-A, BSS-174, and DTH-7 with resistance expressed as slow blighting against four pathogenic isolates of A. solani, were selected for cultivation in disease-prone areas. Disease intensity increased with the age of plants under the same inoculum load. The area under the disease progress curve (AUDPC) was positively correlated with the percentage disease index and negatively with resistance. Calculation of the apparent infection rate (r) was more informative for natural epidemics than for artificial conditions. The sequential apparent infection rate between observation periods was better correlated with disease progress than was the total apparent infection rate between the first and last observations. A double sigmoidal disease progress curve during the same cropping season was characteristic of some varieties when fungal infection took place during the vegetative phase of crop growth. [ABSTRACT FROM AUTHOR]