1,064 research outputs found

    Evaluation of thiamethoxam 70% WS as seed treatment against early sucking pests of tomato

    Get PDF
    The present investigation was carried out at Vegetable Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand during the 2013 and 2014 to evaluate the effectiveness of thiamethoxam, used as seed treatment against the sucking insects of tomato. The seed treatment with thiamethoxam protected tomato seedlings from aphids and thrips at the early season from the onset of seed planting. There was a fast initial effect against the pests then gradually decreased to reach a moderate effect. Data revealed that Thiamethoxam 70% WS @ 4.2 g a.i./kg of seed showed the significant pest reduction followed by Thiamethoxam 70% WS @ 3.85 g a.i./kg of seed. Highest yield was recorded by Thiamethoxam 70% WS @ 4.2 g a.i./kg of seed (28.25 t/ha) closely followed by Thiamethoxam 70% WS @ 3.85 g a.i./kg of seed (25.00 t/ha) as compared to untreated check (20.91t/ha). Percent increase in yield over control was highest (35.10%) in Thiamethoxam 70% WS @ 4.2 g a.i./kg of seed followed by Thiamethoxam 70% WS @ 3.85 g a.i./kg of seed (19.56%). The percent reductions of predators by Thiamethoxam, used as seed treatment, in both the seasons ranged from 1.65- 2.58% which was very minimum. Hence, it was concluded that the seed treatment of tomato with Thiamethoxam 70% WS @ 4.20 g a.i/kg of seed reduced the early season insect-pests (aphid and thrips) and had very less effect of natural enemies population ascompared to control and also increased the fruit yield significantly than other treatments

    Magnetic properties and complex magnetic phase diagram in non centrosymmetric EuRhGe3_3 and EuIrGe3_3 single crystals

    Get PDF
    We report the magnetic properties of two Eu based compounds, single crystalline EuIrGe3_3 and EuRhGe3_3, inferred from magnetisation, electrical transport, heat capacity and 151^{151}Eu M\"{o}ssbauer spectroscopy. These previously known compounds crystallise in the non-centrosymmetric, tetragonal, I4mmI4mm, BaNiSn3_3-type structure. Single crystals of EuIrGe3_3 and EuRhGe3_3 were grown using high temperature solution growth method using In as flux. EuIrGe3_3 exhibits two magnetic orderings at TN1T_{\rm N1} = 12.4 K, and TN2T_{\rm N2} = 7.3 K. On the other hand EuRhGe3_3 presents a single magnetic transition with a TNT_{\rm N} = 12 K. 151^{151}Eu M\"{o}ssbauer spectra present evidence for a cascade of transitions from paramagnetic to incommensurate amplitude modulated followed by an equal moment antiferromagnetic phase at lower temperatures in EuIrGe3_3, the transitions having a substantial first order character. On the other hand the 151^{151}Eu M\"{o}ssbauer spectra at 4.2 and 9 K in EuRhGe3_3 present evidence of a single magnetic transition. In both compounds a superzone gap is observed for the current density J∥J\parallel [001], which enhances with transverse magnetic field. The magnetisation measured up to 14 T shows the occurrence of field induced transitions, which are well documented in the magnetotransport data as well. The magnetic phase diagram constructed from these data is complex, revealing the presence of many phases in the H−TH-T phase space

    Effect of Thermal Annealing on Boron Diffusion, Micro-structural, Electrical and Magnetic properties of Laser Ablated CoFeB Thin Films

    Full text link
    We report on Boron diffusion and subsequent crystallization of Co40_{40}Fe40_{40}B20_{20} (CoFeB) thin films on SiO2_2/Si(001) substrate using pulsed laser deposition. Secondary ion mass spectroscopy reveals Boron diffusion at the interface in both amorphous and crystalline phase of CoFeB. High-resolution transmission electron microscopy reveals a small fraction of nano-crystallites embedded in the amorphous matrix of CoFeB. However, annealing at 400∘^\circC results in crystallization of CoFe with \textit{bcc} structure along (110) orientation. As-deposited films are non-metallic in nature with the coercivity (Hc_c) of 5Oe while the films annealed at 400∘^\circC are metallic with a Hc_c of 135Oe.Comment: 16 pages, 6 figure

    Evidence of spin lattice coupling in MnTiO3_{3}: an x-ray diffraction study

    Full text link
    Here we investigate the temperature evolution of the structural parameters of a potential magnetoelectric material, MnTiO3_{3}. The experimental results reveal interesting temperature dependence of the c/ac/a ratio and the Mn-O bonds which can be divided into three regions. In region I (300 K to 200 K), the above parameters are seen to decrease with decrease in temperature due to thermal effect. In the region II (200 K to 95 K), the decrement in the structural parameters are reduced due the competing intra layer antiferromagnetic interaction setting in ∼\sim 200 K. The c/ac/a ratio are seen to display a minima around 140 K. Below 140 K, the short Mn-O bonds increase suggesting the onset of inter layer antiferromagnetic interaction ∼\sim 100 K. In region III (95 K to 23 K), the antiferromagnetic interaction is fully established. The behaviour of the calculated Mn-O bonds based on first principle calculations are in line with the experimental results. This study demonstrates the importance of spin lattice coupling in understanding the magnetic properties of the compound which is expected to be helpful in revealing the origin of magnetically induced ferroelectricity.Comment: 5 pages, 4 figure

    Tetramer Orbital-Ordering induced Lattice-Chirality in Ferrimagnetic, Polar MnTi2O4

    Full text link
    Using density-functional theory calculations and experimental investigations on structural, magnetic and dielectric properties, we have elucidated a unique tetragonal ground state for MnTi2O4, a Ti^{3+} (3d^1)-ion containing spinel-oxide. With lowering of temperature around 164 K, cubic MnTi2O4 undergoes a structural transition into a polar P4_1 tetragonal structure and at further lower temperatures, around 45 K, the system undergoes a paramagnetic to ferrimagnetic transition. Magnetic superexchange interactions involving Mn and Ti spins and minimization of strain energy associated with co-operative Jahn-Teller distortions plays a critical role in stabilization of the unique tetramer-orbital ordered ground state which further gives rise to lattice chirality through subtle Ti-Ti bond-length modulations
    • …
    corecore