Synthesis and characterization of multiferroic magnetoelectric ceramic composites

Ceramic composites with composition (1−x)[Ba0.85Ca0.15Zr0.1Ti0.9O3] − x[Ni0.7Zn0.3Fe2O4], (0 ≤ x ≤ 100 wt%) were prepared using solid state route. Structural and microstructural analysis confirmed the coexistence of ferroelectric (BCZT) and magnetostrictive (NZFO) phases without any detectable presence of impurity/secondary phases. The composites exhibited ferroelectric, magnetic properties and magnetoelectric coupling responses. Highest coupling coefficient was obtained for composite with 50 wt% NZFO.publishe

Derivation of Nutrient Prices from Household level Food Expenditure Data: Methodology and Applications

In cross-country/cross-region multilateral consumer price level comparisons, differences in the mix of food items consumed in individual countries pose a major problem. Comparison of the level of prices of food items in two countries will be difficult, if the sets of food items consumed in the two countries are very different. However, if the data on average level of intake of major nutrients and some measure of the corresponding nutrient prices is available, a comparison of the level of nutrient prices is possible. At the household level, given the prices of food items actually paid and the corresponding levels of actual intake of different nutrients (from the consumption of various food items), it is possible, in principle, to work out a set of shadow prices of individual nutrients. In this context, it may be mentioned that the shadow prices of nutrients thus derived, being based on households' actual consumption information, would be influenced by the prices of food items consumed, nominal income, household attributes and other preference factors characterizing the individual households. Given such sets of household level nutrient prices and corresponding nutrient intakes for individual countries, a set of multilateral nutrient price index numbers may be worked out and a cross-country comparison of the nutrient price level performed. In this paper a regression analysis-based procedure has been proposed for estimation of household-level unit values of carbohydrates, protein and fat, using a cross-sectional household level data set on food expenditure, total consumer expenditure, quantities of nutrients consumed and related variables. The proposed procedure has been applied to the Indian household level data for the year 1999-2000 using the 55th round Consumer Expenditure Survey of the National Sample Survey Organisation, Govt. of India and subsequently analysed separately for the rural and urban sector of some selected major Indian States.Nutrients, prices, multilateral, comparisons

Low temperature magnetic and magnetocaloric studies in YCr0.85Mn0.15O3 ceramic

We have investigated low temperature magnetic and magnetocaloric properties of manganese (Mn) doped YCr0.85Mn0.15O3 (YCMO) polycrystalline compound, synthesized via solid state reaction route. The lattice volume was found to increase in comparison to that of pristine YCrO3 (YCO) compound. On the other hand, the paramagnetic-antiferromagnetic Néel temperature (TN ∼ 132 K) was found to be lower than that for YCO ceramic. On cooling below TN, under field cooled (FC) mode with an applied magnetic field of 0.02 T, magnetization flipped the polarity from positive to negative at Tcomp = 62 K. Furthermore, the magnetization switching temperature, defined as compensation temperature, exhibited field dependency and decreased with increasing field. Besides, the magnetization reversal phenomenon disappeared under higher applied magnetic field values. For the first time, the magnetocaloric effect for this compound was measured near 36 K through the parameters like magnetic entropy change (−ΔS) = ∼0.186 J kg−1 K−1 and the relative cooling power (RCP) ∼ 6.65 J kg−1, under an applied field of 5 T.publishe

Income and Emission: A Panel Data based Cointegration Analysis

This paper presents the results of an investigation of the causality issue of income-emission relationship based on time series econometric techniques of unit root test, co-integration and related error correction model for a panel data set. Here, the nature of causality between per capita CO2 emission (PCCO2) and per capita GDP (PCGDP) has been examined using a cross country panel data set covering 88 countries for the period 1960 - 90. Using the panel unit root test procedure of Im et al. (1997) (IPS), we have found that the hypothesis of unit root (i.e., non-stationarity) of the time series of PCGDP and PCCO2 can not be rejected for individual country groups. As both the variables are found to follow I(1) process, we next have performed the panel data co-integration test and finally, we have estimated the ECM (for these country groups for which significant income-emission cointegration was obtained) to explore the nature of dynamics implicit in the given panel data set. Our findings suggest that there is more or less a bi-directional causal relationship between income (PCGDP) and CO2 emission (PCCO2) for Africa, Central America, America as a whole, Eastern Europe, Western Europe, Europe as a whole and the World as a whole. That means, the movement of the one variable directly affects the other variable through a feedback system. Thus, the policy makers should be cautious to make proper decision about the control of emission level

Income and Emission: A Panel Data based Cointegration Analysis

This paper presents the results of an investigation of the causality issue of income-emission relationship based on time series econometric techniques of unit root test, co-integration and related error correction model for a panel data set. Here, the nature of causality between per capita CO2 emission (PCCO2) and per capita GDP (PCGDP) has been examined using a cross country panel data set covering 88 countries for the period 1960 - 90. Using the panel unit root test procedure of Im et al. (1997) (IPS), we have found that the hypothesis of unit root (i.e., non-stationarity) of the time series of PCGDP and PCCO2 can not be rejected for individual country groups. As both the variables are found to follow I(1) process, we next have performed the panel data co-integration test and finally, we have estimated the ECM (for these country groups for which significant income-emission cointegration was obtained) to explore the nature of dynamics implicit in the given panel data set. Our findings suggest that there is more or less a bi-directional causal relationship between income (PCGDP) and CO2 emission (PCCO2) for Africa, Central America, America as a whole, Eastern Europe, Western Europe, Europe as a whole and the World as a whole. That means, the movement of the one variable directly affects the other variable through a feedback system. Thus, the policy makers should be cautious to make proper decision about the control of emission level

Structural, electrical, optical and magnetic properties of SmCrO3 chromites: influence of Gd and Mn co-doping

Impact of co-doping of Gadolinium (Gd) and Manganese (Mn) ions on the structural, electrical, optical and magnetic properties of SmCrO3 (SCO) orthochromite compound has been systematically investigated for the first time. The lattice volume expanded with only Mn substitution whereas it shrinks in the co-doped compounds. The tolerance factor decreased while the orthorhombic distortion was found to increase with co-doping. Tilt angle, θ[101] (ο) increased in the co-doped compounds. On the contrary, ∅[010] (ο) initially decreased and then increased. The increased orthorhombic distortion with co-doping also influenced the Raman modes. The electrical resistivity got enhanced in the co-doped samples and its behavior was explained based on Mott's variable range hopping model. Hopping energy and mean hopping distance have also been estimated for the co-doped compounds. The optical bandgap of pristine SCO compound was observed to vary with co-doping, signifying the potential applications of these compounds as photocatalyst. Two compensation temperatures (defined as a temperature where the magnetization changes polarity) were noticed in co-doped compounds. The magnetization reversal was observed in all the co-doped compounds under lower applied magnetic field. The low temperature magnetocaloric effect got enhanced significantly with increasing co-doping content implying the usefulness of these compounds as low temperature refrigerant materials.publishe

Forecasting Hourly Prices in Indian Spot Electricity Market

In this paper, an attempt has been made to forecast the hourly electricity spot prices in India as this is very important for the bidders in the energy exchange for participating in the day-ahead market. Forecasting high frequency data is a challenging task. In forecasting, different variants of ARMA, ARMA-GARCH models are applied in different contexts, but no unequivocal dominance of a particular model exists. In this paper, based on hourly data for several years for all the regions in India, several variants of ARMAX models are estimated, by combining static and dynamic forecasts. Along with ARMA, intra-day, inter-day and hourly variations in prices as well as seasonalities on weekdays, holidays and festive days are incorporated. ARMAX models in this context performed quite well for forecasting horizons of hourly prices of upto 5 days. Interestingly, the ARMAX models provide reasonably good forecasts for day-ahead-market and the simple structure can be quite easily implemented. Such forecasts are not only essential for the players in the spot market, but also provides insights for policymakers as it reveals several aspects of Indian electricity market including the different dimensions of seasonality in demand

Air Quality and Economic Growth: An Empirical Study

This study has been observed an inverse (and sometimes U-shaped) relationship between environmental degradation and per capita real income as opposed to the inverted U-shaped environmental Kuznets curve (EKC) found in many earlier studies. It was felt that a possible explanation of the observed pattern of relationship might be sought in the dynamics of the process of economic growth experienced by the countries concerned. Economic development may strengthen the market mechanism as a result of which the economy may gradually shift from non-market to marketed energy resources that are less polluting. This phenomenon may show up in the form of an inverse relationship, as mentioned above. Also, due to the global technical progress the production techniques available to the countries all over the world are becoming more and more capital intensive and at the same time less polluting. This may mean that, given the income level, the pollution level decreases as the capital intensity of an economy rises. In the present study, it is indeed observed that as capital intensity increases the level of suspended particulate matter (spm) in the atmosphere decreases. Per capita real income is also found to be inversely related to spm partially, but the interaction effect of per capita income and capital-intensity on spm is observed to be positive. This suggests that, given the level of per capita income (capital intensity), a more capital-intensive production technique (a higher per capita income level) would cause less pollution. For spm a surprising result is also obtained, i.e. a U-turn is observed at a very high level of per capita real income (i.e. ~US$12 500 at 1985 US prices). This is possibly indicative of the fact that there are technological limits to industrial pollution control such that beyond a threshold level of income further rise in income cannot be achieved without environmental degradation