White light emission from spin coated Gd2O3:Dy nano phosphors synthesized using polyol technique

Water dispersible Gd2O3:Dy3+ (2%) nanophosphors were synthesized through a facile polyol process and characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM), Dynamic Light Scattering (DLS) and photoluminescence (PL) spectrophotometry. The results of XRD, TEM and DLS show that resultant nanoparticles are single phasic and have spherical shape with 17 to 22% dispersibility. An efficient energy transfer was observed from host to the dopant ions. Characteristic blue and yellow emissions from Dy3+ ions were observed. The CIE coordinates of the nanophosphor lie in the white light region of the chromaticity diagram. Spin coating of the nanophosphor was done on quartz substrate. Bright white luminescence of this film was observed under ultraviolet light with lamda exc = 310 nm.     

Swift heavy ion induced structural modifications in zircon and scheelite phases of ThGeO4

Structural modifications in the zircon and scheelite phases of ThGeO₄ induced by swift heavy ions (93 MeV Ni⁷⁺) at different fluences as well as pressure quenching effects are reported. X-ray diffraction and Raman measurements at room temperature on the irradiated zircon phase of ThGeO₄ indicate the occurrence of stresses that lead to a reduction of the cell volume up to 2% followed by its transformation to a mixture of nano-crystalline and amorphous scheelite phases. Irradiation of the zircon phase at liquid nitrogen temperature induces amorphization at a lower fluence (7.5 × 10¹⁶ ions/m²), as compared to that at room temperature (6 × 10¹⁷ ions/m²). Scheelite type ThGeO₄ irradiated at room temperature undergoes complete amorphization at a lower fluence of 7.5 × 10¹⁶ ions/m² without any volume reduction. The track radii deduced from X-ray diffraction measurements on room temperature irradiated zircon, scheelite and low temperature irradiated zircon phases of ThGeO₄ are, 3.9, 3.5 and 4.5 nm, respectively. X-ray structural investigations on the zircon phase of ThGeO₄ recovered after pressurization to about 3.5 and 9 GPa at ambient temperature show the coexistence of zircon and disordered scheelite phases with a larger fraction of scheelite phase occurring at 9 GPa. On the other hand, the scheelite phase quenched from 9 GPa shows crystalline scheelite phase pattern.     

Emission characteristic of hydrogen and gasoline blend in spark-ignited engine

Hydrogen is an energy carrier that can transform our fossil fuel-dependent economy into a hydrogen economy, which can provide an emission-free transportation fuel. Hydrogen-fuelled engines are known for several advantages, among which is the very low concentration of pollutants in the exhaust gases compared with internal combustion engines using traditional or other alternative fuels. Hydrogen-driven vehicles thus reduce both local and global emissions. It is an energy carrier that can be used in internal combustion engines or fuel cells producing virtually no greenhouse gas emissions when combusted with oxygen. The only significant emission is water vapour. The effect of blending of hydrogen with gasoline is analysed in this current paper. Both HC and NO_x concentration decrease with the increase in hydrogen fractions. The results were analysed by collecting data on different crank angles and at 5%, 10%, 15% and 20% of hydrogen introduction into combustion chamber along with gasoline as base fuel.     

三轴感应电阻率测井新技术

一种新型感应电阻率测井仪器能够提供远离井筒地层的三维信息,提高斜井和倾斜地层的电阻率测量精度,而且不需要接触井壁就能够直接测量地层倾角大小和方位。采用这种高精度三轴电阻率测井仪器可以减少漏掉油气层的机会,加强对储层的认识。     

Non-discrete ant colony optimisation (NdACO) to optimise the development cycle time and cost in overlapped product development

In order to expedite the process of introducing a product to market, organisations have shifted their paradigm towards concurrent engineering. This involves the simultaneous execution of successive activities on the basis of information available in rudimentary form. For this, cross-functional teams sporadically communicate to exchange available updated information at the cost of augmented time and money. Therefore, the aim of this paper is to present a model-based methodology to estimate the optimal amount of overlapping and communication policy with a view to minimising the product development cycle time at the lowest additional cost. In the first step of the methodology, an objective function comprising the cycle time and the cost of the complete project is formulated mathematically. To reach the optimal solution, a novel meta-heuristic, non-discrete ant colony optimisation, is proposed. The algorithm derives its governing traits from the traditional ant algorithms over a discrete domain, but has been modified to search results in a continuous search space. The salient feature of the proposed meta-heuristic is that it utilises the weighted sum of numerous probability distribution functions (PDFs) to represent the long-term pheromone information. This paper utilises a novel approach for pheromone maintenance to adequately update the PDFs after each tour by the ants. The performance of the proposed algorithm has been tested on a hypothetical illustrative example of mobile phones and its robustness has been authenticated against variants of particle swarm optimisation.     

First and second law analyses of a typical solar air dryer system: a case study

This communication presents an experimental study based on energy and exergy analyses of a typical solar air dryer. On the basis of the experimental results, the first and the second law efficiencies are calculated with respect to the available solar radiation. It is found that the second law efficiency is much less than the first law efficiency irrespective of the mass flow rate of the circulating fluid. It is also found that both efficiencies are an increasing function with respect to the mass flow rate of the working fluid. For a particular day, it is also found that first and second law efficiencies fluctuate according to radiation. The results obtained in this article are found to be consistent with those obtained by earlier authors as given in the literature.     

Synthesis and Performance Properties of Cationic Fabric Softeners Derived from Different Fatty Acids and 1(2-Hydroxyethylpiperazine)

Quaternary ammonium salts (otherwise known as “quats”) commonly form the foundation of formulations in the antimicrobial industry. Many studies have been conducted on the biological activity of surfactants derived from fatty acids viz. lauric acid, myristic acid, stearic acid and palmitic acid and palm fatty acid with polyamine, i.e. 1(2-hydroxyethylpiperazine). The present paper investigates the synthesis and surface-active properties of esteramide quats derived from the esterification of the above-mentioned fatty acids and 1(2-hydroxyethylpiperazine) followed by quaternization using dimethyl sulphate (DMS). These derivatives were fully characterized by using Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance (NMR) spectroscopy, and 13C-NMR spectroscopy. In addition to the cationic content, surface tension, CMC (critical micelle concentration), fabric softening, rewettability, emulsification and dispersing power were determined as their surface-active properties.

Low-Temperature Sintering of La(Ca)CrO3 Powder Prepared through the Combustion Process

Ultrafine La(Ca)CrO₃ (LCC) powder was prepared through the glycine–nitrate gel combustion process. It was shown for the first time that the use of relatively inexpensive CrO₃ as a starting material for chromium has potential for the bulk preparation of sinter-active LCC powder. As-prepared powder, when calcined at 700°C, resulted in LCC along with a small amount of CaCrO₄. The calcined powder was found to be composed of soft agglomerates with a particle size of ≈70–290 nm. The cold pressing and sintering of the calcined powder at 1200°C resulted in the mono-phasic La_0.7Ca_0.3CrO₃ with density ≈98% of its theoretical value. This is the lowest sintering temperature ever reported for La_0.7Ca_0.3CrO₃. The conductivity of the sintered La_0.7Ca_0.3CrO₃ at 1000°C was found to be ≈57 S/cm in air. The sintering and electrical behavior achieved for La_0.7Ca_0.3CrO₃ may find application as an interconnect material for high-temperature solid oxide fuel cells if problems with chemical expansion and poor conductivity in fuel can be overcome.     

Effect of tanniniferous Terminalia chebula extract on rumen biohydrogenation, ∆(9)-desaturase activity, CLA content and fatty acid composition in longissimus dorsi muscle of kids

Conjugated linoleic acid, a fatty acid found in milk fat and ruminant meat is one of the functional food components. Modifying fatty acid composition so as to increase CLA and other beneficial PUFA/MUFA level and reducing SFA levels might be a key to enhance the neutraceutical and therapeutic value of ruminant-derived food products. In the present experiment, the effect of supplementation of polyphenol rich Terminalia chebula plant extract at different concentrations (1.06 g/kg and 3.18 g/kg of body weight in T1 and T2 groups, respectively) was investigated on fatty acid composition of rumen fluid, plasma, intramuscular fat and Δ9-desaturase activity in longissimus dorsi muscle of crossbred kids. Total MUFA and PUFA content in muscle were enhanced by 25 and 35%, respectively, whereas SFA was reduced by 20% thereby improving the desaturation index. Δ9-desaturase activity also increased by 47% resulting in an enhancement of total CLA content (58.73%) in muscle.     

Organogel Formation of Soybean Oil with Waxes

Many waxes including plant waxes and animal waxes were evaluated for the gelation ability toward soybean oil (SBO) and compared with hydrogenated vegetable oils, petroleum waxes and commercial non-edible gelling agents to understand factors affecting the gelation ability of a gelator. Sunflower wax (SW) showed the most promising results and all SW samples from three different suppliers could make a gel with concentrations as low as 0.5 wt%. Candelilla wax and rice bran wax also showed good gelation properties, which, however, varied with different suppliers. Gelation ability of a wax is significantly dependant on its purity and detailed composition. A wax ester with longer alkyl chains has significantly better gelation ability toward SBO than that with shorter alkyl chains indicating that the chain length of a component in a wax such as wax ester is an important factor for gelation ability. The SW–SBO organogel showed increased melting point with increased SW content, showing the melting point range from about 47 to 65 °C with 0.5–10 wt% SW. The effects of cooling rate on crystal size and firmness of a gel were investigated. The dependence of firmness on cooling rate was so significant that the desired texture of an organogel could be achieved by controlling the cooling rate in addition to controlling the amount of gelling agent. This research reveals that a small amount of food grade plant waxes including SW may replace a large amount of the hardstock containing trans-fat or saturated fat.