Exploring the possibility of enhancing the figure-of-merit ( >> 2) of Na0.74_{0.74}CoO2_{2}: A combined experimental and theoretical study

Search of new thermoelectric (TE) materials with high \textit{figure-of-merit} (ZT) is always inspired the researcher in TE field. Here, we present a combined experimental and theoretical study of TE properties of Na$_{0.74}$CoO$_{2}$ compound in high-temperature region. The experimental Seebeck coefficient (S) is found to vary from 64 to 118 $\mu$V/K in the temperature range $300-620$ K. The positive values of S are indicating the dominating p-type behaviour of the compound. The observed value of thermal conductivity ($\kappa$) is $\sim$ 2.2 W/m-K at 300 K. In the temperature region $300-430$ K, the value of $\kappa$ increases up to $\sim$ 2.6 W/m-K and then decreases slowly till 620 K with the corresponding value of $\sim$ 2.4 W/m-K. We have also carried out the theoretical calculations and the best matching between experimental and calculated values of transport properties are observed in spin-polarized calculation within DFT+\textit{U} by chosen \textit{U} = 4 eV. The maximum calculated value of ZT is found to be $\sim$ 0.67 at 1200 K for p-type conduction. Our computational study suggests that the possibility of n-type behaviour of the compound which can lead to a large value of ZT at higher temperature region. Electron doping of $\sim$ 5.1$\times$10$^{20}$ cm$^{-3}$ is expected to give rise the high ZT value of $\sim$ 2.7 at 1200 K. Using these temperature-dependent ZT values, we have calculated the maximum possible values of efficiency ($\eta$) of thermoelectric generator (TEG) made by p and n-type Na$_{0.74}$CoO$_{2}$. The present study suggests that one can get the efficiency of a TE cell as high as $\sim$ 11$\%$ when the cold and hot end temperature are fixed at 300 K and 1200 K, respectively. Such high values of ZT and efficiency suggest that Na$_{0.74}$CoO$_{2}$ can be used as a potential candidate for high-temperature TE applications

Seaweed extract as a biostimulant for legume crop, green gram

The aim of this research is to investigate the effect of seaweed extracts obtained from the marine green algae, Ulva lactuca Linnaeus, Caulerpa scalpelliformis (R. Brown ex Turner) C. Agardh, brown algae Sargassum plagiophyllum C. Agardh, Turbinaria conoides (J. Agardh) Kutzing, Padina tetrastromatica Hauck, Dictyota dichotama (Hudson) J. V. Lamouroux on the stimulate germination, growth parameters of the Vigna radiata. The present study reveals the seeds germination, fresh weight and dry weight of shoots and roots. These results suggested that seaweed extracts stronger induce seed germination and growth parameters

Design Analysis of Brushless Direct Current Generator

In this work, optimisation of a brushless direct current (BLDC) generator design was undertaken by carrying out an electromagnetic and computational fluid dynamic study. The studies were carried out for different loading-overloading conditions and angular speeds, keeping in consideration the required electrical and thermal parameters, firstly for the initial design and then for optimised designs. In the initial phase, transient electromagnetic simulations were done using Ansys Maxwell to estimate power output, flux densities, heat losses et al. In the next phase, steady state conjugate heat transfer simulations using frozen rotor method for rotating domains were carried out in Ansys CFX using the heat loss values obtained from electromagnetic study in the first phase. The results from conjugate heat transfer were obtained in the form of temperature and flow parameters. After a thorough study and comparison of the results for different designs, obtained in the two phases, it was seen one of the optimised designs showed better electromagnetic, thermal and flow parameters as compared to the initial design and satisfied all the optimum electrical and thermal parameters

Dual pillars of hotel restaurant food quality satisfaction and brand loyalty

Purpose: The purpose of this paper is to investigate the impact of service quality (physical quality and staff behaviour) and brand equity (brand quality, brand awareness and brand image) on hotel restaurant food quality satisfaction and brand loyalty among international and local travellers in Malaysia. Design/methodology/approach: A total of 354 valid questionnaires were collected to assess the measurement and structural model for reflective latent constructs using the two steps of covariance-based structural equation modelling. Findings: The research findings suggest that while travellers’ nationality moderates the path between physical quality, staff behaviour and brand image on food quality satisfaction, it does not moderate the relationship between brand quality and brand awareness on food quality satisfaction. This finding further suggests that towards enhancing service quality and brand equity on food quality satisfaction and brand loyalty, managers should understand the important distinctions between international and local travellers. Originality/value: Previous studies have mostly examined the impact of brand equity and service quality towards tourist satisfaction and very few studies have examined the impact of restaurant service quality and brand equity on consumer satisfaction and brand loyalty specifically among international and local travellers. This is one of the first few studies providing empirical evidence and discussions in this area

Effect of nurse culture on inducing division of isolated pollen protoplasts of Hevea brasiliensis

Haploids are of great relevance in crop improvement of Hevea, a highly heterozygous tree species with a long breeding cycle. The isolation and culture of pollen protoplasts may be a viable proposition for raising haploid plants/ homozygous lines in Hevea. The present work envisages the development of a method for the isolation and culture of pollen protoplasts of Hevea. Effect of different nurse cultures on the development of cultured protoplasts has been studied. Intact pollen grains were isolated from mature male flowers of Hevea prior to opening. Viable protoplasts in high yield could be isolated from these pollen grains when exposed to a mixture of 0.5 per cent cellulase and 0.05 per cent pectolyase in the presence of the osmotic stabilizers 0.6 M mannitol and 0.3 M sorbitol. These protoplasts were partially purified and cultured in the nutrient medium with three different nurse cultures namely embryogenic calli from Hevea, tobacco and carrot. Division of the cultured protoplasts leading to the formation of a few micro-colonies was observed in the medium containing 0.8 mg l-1 2, 4-D and 0.5 mg l-1 BA and enriched with Hevea nurse culture. Cultures with micro-colonies are dark incubated for further development. This is the first report of division of pollen protoplasts and micro-colony formation in Hevea brasiliensis

Drought tolerance in MnSOD transgenic Hevea brasiliensis in a dry sub-humid environment

One year old bud-grafted plants of MnSOD transgenic Hevea lines (L1 and L2) and an untransformed line of clone RRII 105 were used in the present study to evaluate their physiological performance in a dry sub-humid environment by withholding irrigation and to assess the recovery by re-watering. The dry matter partitioning was more towards the root in transgenic lines (55% and 60% in Ll and L2, respectively) but, was less in the untransformed RRII 105 (43%). After six days of moisture stress in polybags, pre-dawn leaf water potential and relative water content declined in all the lines, however, transgenic line L1 showed higher tissue water content throughout the drought as well as recovery period. Chlorophyll content did not show any significant reduction. Net photosynthetic rate (PN) declined rapidly and it reached near zero on the third day of drought imposition except for line L1, which showed lesser decline in PN. The decline in stomatal conductance (gs) was more rapid than PN in all the lines. On re-watering, recovery of PN and gs was better in the transgenic lines than untransformed RRII 105, which did not recover fully from the drought impact. Antioxidant enzymes, superoxide dismutase and peroxidase did not show a definite trend in their activities in these lines. However, it was found that the transgenic line L1 had better drought tolerant capacity in terms of lesser inhibition of photosynthetic rate under drought and faster recovery on re-watering

Creep strength behavior of boron added P91 steel and its weld in the temperature range of 600–650 degree C

One of the promising ways for mitigation of Type IV cracking – a failure by cracking at the intercritical /fine grained heat affected zone, a life limiting problem in advanced 9–12 Cr ferritic steel weld like that of P91 is through modification of alloy composition by addition of boron. Addition of boron was observed to improve the microstructure at the weld zone and hence the creep strength. In the present work, boron (100 ppm with controlled nitrogen) added P91 steel after normalizing at 1050C and 1150C and tempered at 760C were studied for the creep behavior in the base metal and welded condition in the temperature range of 600–650C. Creep strength was characterized in terms of stress and temperature dependence of creep rate and rupture time. Weld creep life was reduced compared to the base metal with rupture occurring at the ICHAZ (Type IV crack). However at longer time (at lower stress levels) exposure creep crack moves from weld metal to HAZ (Type II crack). Rupture life was found to superior for the base and weld in the boron containing steel when higher normalizing temperature is used. Estimation of 10 5 h was attempted based on short term rupture data available and weld strength factors were calculated. Observed values are better for P91BH condition than the values for P91BL condition as well as those available for P91 in open literatur

High frequency Agrobacterium mediated genetic transformation in rubber tree via. vacuum infiltration

In a tree species like Hevea brasiliensis, genetic transformation offers a viable approach for crop improvement within a short period. Hevea being highly recalcitrant to in vitro culture, an efficient transformation protocol is necessary for generating large number of transgenic plants with stable foreign gene expression. After several modifications in the initial transformation protocol, the transformation frequency was increased to 14 per cent using proliferated anther callus. Therefore, vacuum infiltration was attempted for enhancing the transformation frequency. In the present work the conditions for vacuum infiltration viz. vacuum pressure and period of infiltration were standardized. Vacuum infiltration at 30 psi pressure for 10 minutes was found to be ideal for getting high frequency transformation in H. brasiliensis. Irrespective of the gene constructs experimented, transformation frequency was significantly improved by adopting vacuum infiltration. Employing this technique, the transformation efficiency of MnSOD gene construct with FMV34S promoter could be enhanced from 14 to 50 percent

Development of cost-effective SNP assays for chickpea genome analysis and breeding

A total of 1499 ESTs generated from 26 different Cicer species, available in the public domain at the time of analysis, were used for in silico identification of SNPs using the bioinformatic tools developed at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) (http://hpc.icrisat.org/PBSWeb). Cluster analysis provided a total of 118 clusters, of which 11 clusters contained sequences from more than one Cicer species. Further, these clusters were assembled into 19 contigs and 184 putative SNPs were identified in 15 contigs. However, only 73 SNPs involved restriction enzyme sites for development of the CAPS assays as identified through the SNP2CAPs program. Primer pairs were designed for only 8 contigs (CL3a, CL3c, CL3d, CL3e, CL4a, CL10, CL20 and CL99) which had SNPs, resulting in putative recognition sites to commonly used restriction enzymes. Results of the demonstrates the utility of Cicer EST resources and the availability of bioinformatics analysis pipelines for the large-scale identification of SNPs on the HPC (High Performance Computer) at ICRISAT and the development of costeffective CAPS assay for SNP genotyping. It is anticipated that the availability of large number of ESTs from more than one genotype of cultivated chickpea (C. arietinum) in the near future will make it possible to develop larger number of SNPs in cultivated chickpea germplasm for genome analysis and breeding application