884 research outputs found

    On Weakly Symmetric and Weakly Conformally Symmetric Spaces Admitting Veblen Identities

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    In the present paper some properties involving curvature tensor,conformal curvature tensor, Ricci tensor and scalar curvature, on weakly symmetric, weakly conformally symmetric and pseudo symmetric spaces are obtained

    Performance and Emission Characteristics Of CI Engine Using Waste Cooking Oil As An Alternate Fuel

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    In presence scenario,thegreatest potential represent as biodiesel production. The major drawbacks of the petroleum diesel, producing emission pollutants from the diesel engines to the environment. To avoid such problem, concentrating on alternate fuel. It plays an important role for the non-disturbance of the atmosphere. Waste cooking oil (WCO) was used to produce biodiesel fuel in order to reduce wastes polluting the environment. This paper deals on impact of biodiesel performance and emission characteristics of CI engine. But the larger viscosity of any waste cooking oil (WCO) is found major problem in use of an engine directly. The properties of fuel such as calorific value, flash point and cetane number of the biodiesel were to be analysed. The performance and emission tests were carried out by B25, B50, B75 and B100 blends of waste cooking palm oil at different loads and such results were compared with petroleum diesel at 200 bar and 230btdc and 210bar and 230btdc. This Performance results reveal that the biodiesel gives higher brake thermal efficiency and lower brake-specific fuel consumption with the different blendingrsquos. Emission results showed that in most cases, NOx is increased, and HC, CO, and PM emissions are decreased. Through this experimental test which type of blending was found the best suitable for engine. In this paper, various blends of waste cooking palm oil and varying the injection parameters such as injection timing, crank angle to increase the performance of an engine and mutually reduces the emissions without any modification of diesel engine

    LACHESIS restricts gametic cell fate in the female gametophyte of Arabidopsis

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    In flowering plants, the egg and sperm cells form within haploid gametophytes. The female gametophyte of Arabidopsis consists of two gametic cells, the egg cell and the central cell, which are flanked by five accessory cells. Both gametic and accessory cells are vital for fertilization; however, the mechanisms that underlie the formation of accessory versus gametic cell fate are unknown. In a screen for regulators of egg cell fate, we isolated the lachesis (lis) mutant which forms supernumerary egg cells. In lis mutants, accessory cells differentiate gametic cell fate, indicating that LIS is involved in a mechanism that prevents accessory cells from adopting gametic cell fate. The temporal and spatial pattern of LIS expression suggests that this mechanism is generated in gametic cells. LIS is homologous to the yeast splicing factor PRP4, indicating that components of the splice apparatus participate in cell fate decisions

    MICROWAVE DRYING OF ALOE VERA (ALOE BARBADENSIS MILLER): MATHEMATICAL MODELING, KINETICS AND MASS TRANSFER ASPECTS

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    Aloe vera has extensive application in food and pharmaceutical industry in fact contains 97 percent of water. It’s perishable in nature and poor shelf life makes it essential to study the drying characteristics of aloe vera. The objective of this present study is to investigate the effect of different microwave (MW) respective power levels (180 , 360 ,540 , 720 and 900 Watts ) regarding the  moisture ratio (MR), drying rate (DR), effective moisture diffusivity (EMD), specific energy consumption (SEC) and drying efficiency (DE) of aloe vera. The drying process took 70 - 26 .5 minutes for attainment of equilibrium moisture content. A mathematical model done by Midilli et al.  is considered to be the best and most suitable for a drying conditions among the various thin layer models. The effective moisture diffusivity value at 180 Watts (W) of MW power was found as 4.5 × 10-8 m2/sec. while it was raised to 9.45 x10-7 m2/sec at 900 W in this study. Lowest energy consumption 1.4 MJ/Kg water and maximum drying efficiency occurred at higher microwave power level 900 Watts due to less drying duration (time)

    FUZZY COST OVERRUN ANALYSIS MODEL FOR CONSTRUCTION PROJECT

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    Now a day’s many factors which affect the productivity in construction project. Due to this delay factors time and cost overrun in a project. In this research helps to identify the most important factors that affect the productivity and form a modelling using fuzzy logic. The data’s were collected through questionnaire survey from engineers, contractors and clients worked within the various construction industries. The collected data’s were analyzed using relative importance index (RII) and ranking the factors based on percentage of relative importance and also this paper presents an application of fuzzy logic for developing delay factors causes cost overrun  model using Fuzzy toolbox of MATLAB Program software. The results can facilitate the construction industry to take measures the delay factors causes cost overrun in construction projects

    Synthesis and solution properties of comblike polymers from octadecyl methacrylate and acrylic acid

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    Amphiphilic polymers consisting of a statistical distribution of octadecyl methacrylate (ODMA) and acrylic acid in respective molar ratios of 83-22 and 17-78 mol% and in a molecular-weight range of 2.35-4.70×104 gmol-1 have been synthesized. The series of polymers consisting of various mole fractions of ODMA and acrylic acid are expected to exhibit unique characteristics resembling ionomer to hydrophobically modified polyelectrolytes. The changes in the I3/I1 emission intensity ratios of pyrene, occurring in the presence of tetrahydrofuran (THF) solutions of the polymers have been taken as the main basis for inferring solution structures. The polymers are found to form random-coil to collapsed-coil/aggregated structures in THF solvent depending on the copolymer compositions. The polymer consisting of 83 mol% ODMA and 17 mol% acrylic acid behaves as an ionomer, capable of forming collapsed-coil structures at concentrations of 0.02 gml-1 and above as shown by a very high I3/I1 of 1.20 (I3/I1 of pyrene in THF is 0.85). In contrast, the poly(octadecyl methacrylate) homopolymer and the sets of copolymers consisting of a very high proportion of acrylic acid to an extent of 73 mol% and above contribute to almost negligible or very small changes in I3/I1 similar to the homopolymer, poly(octadecyl methacrylate), suggesting the formation of random-coil structures

    How do evaporating thin films evolve? Unravelling phase-separation mechanisms during solvent-based fabrication of polymer blends

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    Solvent-based fabrication is a flexible and affordable approach to manufacture polymer thin films. The properties of products made from such films can be tailored by the internal organization (morphology) of the films. However, a precise knowledge of morphology evolution leading to the final film structure remains elusive, thus limiting morphology control to a trial and error approach. In particular, understanding when and where phases are formed, and how they evolve would provide rational guidelines for more rigorous control. Here, we identify four modes of phase formation and subsequent propagation within the thinning film during solvent-based fabrication. We unravel the origin and propagation characteristics of each of these modes. Finally, we construct a mode diagram that maps processing conditions with individual modes. The idea introduced here enables choosing processing conditions to tailor film morphology characteristics and paves the ground for a deeper understanding of morphology control with the ultimate goal of precise, yet affordable, morphology manipulation for a large spectrum of applications

    Electrochemical behaviour of some alkyl substituted N-hydroxy-2,6-diarylpiperidin-4-one thiosemicarbazone and the antifungal studies of the products

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    A series of 3-ethyl-2,6-diarylpiperidin-4-one thiosemicarbazone and 3,5-dimethyl-2,6-diarylpiperidin-4-one thiosemicarbazone were synthesised. The thiosemicarbazones were subjected to cyclic voltammetric study using graphite electrode with variable scan rate at moderate acidic conditions maintained in the electrolytic solution. The reduction takes place by two electron transfer and the reaction is pH dependent. The reduced products were isolated and purified by column chromatography. The structure was proved by 1H and 13C NMR spectroscopy. The electrode process was found to be irreversible and diffusion controlled. Further the products were analysed for anti fungal activity in which nitro substituted compound showed high inhibition towards the fungi Asperillus nige

    Plant Geometry, Macro and Micro Nutrients on Growth and Growth Analysis of Dual Purpose Sorghum under Rainfed Vertisol Condition

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    Field experiment was conducted at Agricultural Research Station, Kovilpatti during rabi season (October 2017 to January 2018) to find out the suitable plant geometry, levels of fertilizers and foliar spray of micronutrients (Zn and Fe) at 15, 30 and 45 DAS to improve the growth and yield of sorghum variety K12 (dual purpose). The experiment was laid out in randomized block design with three replication and twelve treatments. The treatment consists of two plant geometry, three different dose of fertilizer and foliar spray of micronutrients viz., 0.5% ZnSO4 + 0.2% FeSO4 at 15, 30 and 45 DAS. Observation on growth parameters, growth analysis and finally grain and stover yield were recorded. The experimental results shows that reduced plant spacing of  30 × 15 cm together with enhanced application of 50:25:25 kg NPK ha-1 + foliar spray of 0.5% ZnSO4 + 0.2% FeSO4 at 15, 30 and 45 DAS significantly increased the growth parameters viz., plant height, stem girth and days to flowering. This attributes ultimately resulted in higher grain (3961 kg ha-1) and stover (13972 kg ha-1) yield of dual purpose sorghum compared to recommended practice of rainfed sorghum having 45 × 15 cm spacing and application of recommended 40:20:0 kg NPK ha-1 alone
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