83 research outputs found

    Austempered ductile iron (ADI) : influence of austempering temperature on microstructure, mechanical and wear properties and energy consumption

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    Alloyed Ductile iron austenitized at 840°C for 30 min in a special sealed austempering furnace, was austempered for 30 min in molten salt mixture at 4 trial temperatures of 300 °C, 320 °C, 340 °C and 360°C. Tensile strength, yield strength, percentage elongation and impact energy were evaluated for the as-cast and austempered samples. Microstructures were investigated using microscopy coupled with analyzing software and a scanning electron microscopy. The specific wear of samples was tested using pin-on-disc wear testing machine. X-ray diffraction was performed to calculate the amount of retained austenite present in the ausferrite matrix. As cast microstructure consists of ferrite and pearlite, whereas ADI contains a mixture of acicular ferrite and carbon enriched austenite called “ausferrite”. Hardness and strength decreased, whereas ductility and impact strength improved with increase in austempering temperature. XRD analysis revealed that the increase in austempering temperature increases the retained austenite content. Decrease in wear resistance with austempering temperature was observed. Modified Quality Index (MQI) value was envisaged incorporating tensile strength, elongation and wear resistance. MQI for samples austempered at 340°C and 360°C showed better combination of properties. About 8% reduction in energy consumption is gained when the heat treatment parameters are optimized

    Sinteza i farmakološko ispitivanje novih 4-(3-etilfenil)-1-supstituiranih 4H-[1,2,4]triazolo[4,3-a]kinazolin-5-ona kao nove klase H1-antihistaminika

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    A series of novel 4-(3-ethylphenyl)-1-substituted-4H-[1,2,4]triazolo[4,3-a]quinazolin-5-ones (4a-j) were synthesized by the cyclization of 3-(3-ethylphenyl)-2-hydrazino-3H-quinazolin-4-one (3) with various one-carbon donors. The starting material, compound 3, was synthesized from 3-ethyl aniline by a new innovative route with improved yield. When tested for their in vivo H1-antihistaminic activity on conscious guinea pigs, all test compounds protected the animals from histamine induced bronchospasm significantly. Compound 4-(3-ethylphenyl)-1-methyl-4H-[1,2,4]triazolo[4,3-a]quinazolin-5-one (4b) emerged as the most active compound of the series and it is more potent (74.6 % protection) compared to the reference standard chlorpheniramine maleate (71 % protection). Compound 4b shows negligible sedation (10 %) compared to chlorpheniramine maleate (30 %). Therefore compound 4b can serve as the leading compound for further development of a new class of H1-antihistamines.Ciklizacijom 3-(3-etilfenil)-2-hidrazino-3H-kinazolin-4-ona (3) s različitim donorima jednog C atoma sintetizirana je serija novih 4-(3-etilfenil)-1-supstituiranih 4H-[1,2,4]triazolo[4,3-a]kinazolin-5-ona (4a-j). Početni spoj 3 pripravljen je iz 3-etil anilina na novi, inovativni način, s poboljšanim iskorištenjem. U testovima in vivo na zamorcima, svi testirani spojevi pokazali su značajno zaštitno djelovanje protiv bronhospazma induciranog histaminom. Spoj 4-(3-etilfenil)-1-metil-4H-[1,2,4]triazolo[4,3-a]kinazolin-5-on (4b) najaktivniji je među testiranim spojevima (zaštita 74.6 %) i jači od referentnog standarda klorfeniramin maleata (zaštita 71 %). Spoj 4b pokazuje zanemarivu sedaciju (10 %) u usporedbi s klorfeniramin maleatom (30 %). Stoga spoj 4b može biti vodeći spoj za daljnji razvoj nove klase H1-antihistaminika

    Tool wear monitoring using neuro-fuzzy techniques: a comparative study in a turning process

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    Tool wear detection is a key issue for tool condition monitoring. The maximization of useful tool life is frequently related with the optimization of machining processes. This paper presents two model-based approaches for tool wear monitoring on the basis of neuro-fuzzy techniques. The use of a neuro-fuzzy hybridization to design a tool wear monitoring system is aiming at exploiting the synergy of neural networks and fuzzy logic, by combining human reasoning with learning and connectionist structure. The turning process that is a well-known machining process is selected for this case study. A four-input (i.e., time, cutting forces, vibrations and acoustic emissions signals) single-output (tool wear rate) model is designed and implemented on the basis of three neuro-fuzzy approaches (inductive, transductive and evolving neuro-fuzzy systems). The tool wear model is then used for monitoring the turning process. The comparative study demonstrates that the transductive neuro-fuzzy model provides better error-based performance indices for detecting tool wear than the inductive neuro-fuzzy model and than the evolving neuro-fuzzy model

    Using Barkhausen Noise to Measure Coating Depth of Coated High-Speed Steel

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    Coated high-speed steel tools are widely used in machining processes as they offer an excellent tool life to cost ratio, but they quickly need replacing once the coated layer is worn away. It would be therefore useful to be able to measure the tool life remaining non-destructively and cheaply. To achieve this, the work presented here aims to measure the thickness of the coated layer of high-speed cutting tools by using Barkhausen noise (BHN) techniques. Coated high-speed steel specimens coated with two different materials (chromium nitride (CrN), titanium nitride (TiN)) were tested using a cost-effective measuring system developed for this study. Sensory features were extracted from the signal received from a pick-up coil and the signal features, Root mean square, peak count, and signal energy, were successfully correlated with the thickness of the coating layer on high-speed steel (HSS) specimens. The results suggest that the Barkhausen noise measuring system developed in this study can successfully indicate the different thickness of the coating layer on CrN/TiN coated HSS specimens

    Sorghum improvement (1980–2010): Status and way forward

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    Sorghum (Sorghum bicolor) is the fifth most important cereal crop globally and is the dietary staple of more than 500 million people in over 90 countries, primarily in the developing world (Reddy et al. 2010). With its C4 photosynthetic pathway, it is adapted to a wide range of environmental conditions. It has multiple uses as a food, feed, fodder, fuel and fiber crop (Paterson et al. 2009). More than 35 percent of world sorghum production is going for food consumption (Awika and Rooney 2004) by the poorest of the poor in the largely low-income deficit countries. Worldwide, it is grown on about 40 million ha, of which about 9 million ha are cultivated in Asia; of this the largest area is in India (7.53 milion ha) which has a production of 7.25 million t (FAOSTAT 2011)

    Postrainy season sorghum: Constraints and breeding approaches

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    Sorghum (Sorghum bicolor) is the fifth most important cereal crop in the world. Different types of sorghum are recognized. These are: grain sorghum, dual purpose (grain and fodder) sorghum, fodder sorghum, forage sorghum and sweet stalk sorghum. Also two types of sorghums are noted based on the season of adaptation; these are rainy (wet) season or postrainy (dry) season sorghum. There are two distinct sorghum growing seasons in India, kharif (rainy season; June–October) and rabi (postrainy season; October–January). In India, the grain productivity is about 1.2 t ha-1 in the rainy season, and about 0.8 t ha-1 in the postrainy season whereas the global grain productivity of sorghum is 1.4 t ha-1 (FAOSTAT 2011). The grain sorghum requirements for these two seasonal adaptations are quite diverse due to different agroclimatic conditions (Rana et al. 1997). There has been a significant decline in area under grain and dual purpose sorghum during the rainy season due to grain molds, but the area has remained stable in the postrainy season where mostly dual purpose sorghums are cultivated

    MGEx-Udb: A Mammalian Uterus Database for Expression-Based Cataloguing of Genes across Conditions, Including Endometriosis and Cervical Cancer

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    Gene expression profiling of uterus tissue has been performed in various contexts, but a significant amount of the data remains underutilized as it is not covered by the existing general resources.). The database can be queried with gene names/IDs, sub-tissue locations, as well as various conditions such as the cervical cancer, endometrial cycles and disorders, and experimental treatments. Accordingly, the output would be a) transcribed and dormant genes listed for the queried condition/location, or b) expression profile of the gene of interest in various uterine conditions. The results also include the reliability score for the expression status of each gene. MGEx-Udb also provides information related to Gene Ontology annotations, protein-protein interactions, transcripts, promoters, and expression status by other sequencing techniques, and facilitates various other types of analysis of the individual genes or co-expressed gene clusters.In brief, MGEx-Udb enables easy cataloguing of co-expressed genes and also facilitates bio-marker discovery for various uterine conditions

    Altitudinal variation in soil organic carbon stock in coniferous subtropical and broadleaf temperate forests in Garhwal Himalaya

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    <p>Abstract</p> <p>Background</p> <p>The Himalayan zones, with dense forest vegetation, cover a fifth part of India and store a third part of the country reserves of soil organic carbon (SOC). However, the details of altitudinal distribution of these carbon stocks, which are vulnerable to forest management and climate change impacts, are not well known.</p> <p>Results</p> <p>This article reports the results of measuring the stocks of SOC along altitudinal gradients. The study was carried out in the coniferous subtropical and broadleaf temperate forests of Garhwal Himalaya. The stocks of SOC were found to be decreasing with altitude: from 185.6 to 160.8 t C ha<sup>-1 </sup>and from 141.6 to 124.8 t C ha<sup>-1 </sup>in temperature (<it>Quercus leucotrichophora</it>) and subtropical (<it>Pinus roxburghii</it>) forests, respectively.</p> <p>Conclusion</p> <p>The results of this study lead to conclusion that the ability of soil to stabilize soil organic matter depends negatively on altitude and call for comprehensive theoretical explanation</p
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