Transport and Magnetic Properties of FexVse2 (x = 0 - 0.33)

We present our results of the effect of Fe intercalation on the structural, transport and magnetic properties of 1T-VSe2. Intercalation of iron, suppresses the 110K charge density wave (CDW) transition of the 1T-VSe2. For the higher concentration of iron, formation of a new kind of first order transition at 160K takes place, which go on stronger for the 33% Fe intercalation. Thermopower of the FexVSe2 compounds (x = 0 - 0.33), however do not show any anomaly around the transition. The intercalation of Fe does not trigger any magnetism in the weak paramagnetic 1T-VSe2, and Fe is the low spin state of Fe3+.Comment: 7 pages, 8 figures, 2 table

Energy input–output analysis and mechanization status for cultivation of rice and maize crops in Sikkim

Rice and maize are main cereal crops cultivated in Sikkim.  In this paper energy input–output and the level of agricultural mechanization for cultivation of rice and maize in Sikkim state of India has been presented.  The data were collected on area under rice and maize crops, sources of power and agricultural tools/implements used total production through village survey.  It has been observed that the traditional practices of cultivation of rice and maize crops consumed an average energy input of 3338.984 MJ ha-1 and 4386.435 MJ ha-1 respectively.  Data analysis showed that about 60% of the total input energy in the present cultivation practices comes from human and animal power sources.  The output–to–input energy ratio was observed to be 7.66 and 5.86 for rice and maize, respectively.  The observational estimate showed that average productivity of rice and maize crop in the region is only 924.0 kg ha-1 and 431.0 kg ha-1, respectively, which is very low.  Mechanization and machine energy indices were found to stand at a value of 0.3618 and 0.3244, respectively for rice crop cultivation, and 0.2612 and 0.2111, respectively for maize crop cultivation.  The average farm power availability in the state has been estimated as 0.70 kW ha-1.   Keywords: agricultural mechanization in Sikkim, energy input and output, rice and maize crops, grain productivit

High Entropy Alloy Catalytic Action on MgH2 Hydrogen Storage Materials

Magnesium hydride (MgH2) is the mostly used material for solid-state hydrogen storage. However, their slow kinetics and highly unfavorable thermodynamics make them unsuitable for the practical applications. The current study describes the unusual catalytic action of a new class of catalyst, a high-entropy alloy (HEA) of Al20Cr16Mn16Fe16Co16Ni16, on the de/re-hydrogenation properties of MgH2. The onset desorption temperature of MgH2 is reduced significantly from 376 {\deg}C (for pristine MgH2) to 338 degC when it is catalyzed with a HEA-based catalyst. On the other hand, a fast de/re-hydrogenation kinetics of MgH2 was observed during the addition of HEA-based catalyst. It ab sorbs 6.1 wt% of hydrogen in just 2 minutes at a temperature of 300 degC under 10 atm hydrogen pressure and desorbs ~ 5.4 wt% within 40 minutes. At moderate temperatures and low pressure, the HEA-based catalyst reduced desorption temperatures and improved re-hydrogenation kinetics. Even after 25 cycles of de/re-hydrogenation, the storage capacity of MgH2 catalyzed with the leached version of HEA degrades negligibly.Comment: 23 pages, 12 Figures, 2 Tabl