Effectiveness of 3D Geoelectrical Resistivity Imaging using Parallel 2D Profiles

Acquisition geometry for 3D geoelectrical resistivity imaging in which apparent resistivity data of a set of parallel 2D profiles are collated to 3D dataset was evaluated. A set of parallel 2D apparent resistivity data was generated over two model structures. The models, horst and trough, simulate the geological environment of a weathered profile and refuse dump site in a crystalline basement complex respectively. The apparent resistivity data were generated for Wenner–alpha, Wenner–beta, Wenner–Schlumberger, dipole–dipole, pole–dipole and pole–pole arrays with minimum electrode separation, a (a = 2, 4, 5 and 10 m) and inter-line spacing, L (L = a, 2a, 2.5a, 4a, 5a and 10a). The 2D apparent resistivity data for each of the arrays were collated to 3D dataset and inverted using a full 3D inversion code. The 3D imaging capability and resolution of the arrays for the set of parallel 2D profiles are presented. Grid orientation effects are observed in the inversion images produced. Inter-line spacing of not greater than four times the minimum electrode separation gives reasonable inverse models. The resolution of the inverse models can be greatly improved if the 3D dataset is built by collating sets of orthogonal 2D profile

Effect of planting techniques and weed control treatments on growth and yield of wheat

A field experiment was conducted to study the effect of different planting techniques (conventional drill sowing at 16, 18 and 20 cm row spacing and bed planting with two and three rows in main plots) and weed control treatments (pinoxaden 50 g/ha, ready-mix (RM) of carfentrazone and metsulfuron 25 g/ha and pinoxaden 50 g/ha + RM of carfentrazone and metsulfuron 25 g/ha in subplots) on growth and productivity of wheat. The grain yield under row spacing 18 cm (53.30 q/ha), and 20 cm (52.02 q/ha), and three rows bed planting (51.96 q/ha) were recorded statistically at par with each other and significantly higher than 16 cm (49.37 q/ha) row spacing and two row bed planting (48.53 q/ha). Gross returns (Rs. 95637/ha) and net returns (Rs. 43929/ha) and B:C ratio (1.85) were record-ed higher under 18 cm row spacing compared to other planting techniques. Tank mixed application of pinoxaden 50 g/ha + RM of carfentrazone and metsulfuron 25 g/ha applied at 35 days after sowing (DAS) controlled both grassy and broad leaved weeds effectively with lower values of weed dry matter accumulation (7.67 g/ha) and produced growth parameters, yield attributes and yield (53.16 q/ha) at par with weed free treatment. In light of the results to maximise productivity, 18 cm row spacing may be practiced and tank mix application of pinoxaden (50 g/ha) + RM of carfentrazone and metsulfuron (25 g/ha) is recommended to reduce losses due to complex weed flora in wheat

Effect of different dates of sowing on yield attributes, yield and quality of Barley (Hordeum vulgare L.) cultivars

A study was conducted during rabi2013-14 at Barley Research Area of CCS Haryana Agricultural University, Hisar with the objective to study the effect of different date of sowing on growth, yield and quality characters of barley cultivars. The experiment was laid out in a split plot design with five date of sowing (30th October, 10th, 20th, 30th November and 10th December) in main plots and four cultivars (BH 902, RD 2552, DWRUB 52 and RD 2668) kept in sub plots replicated thrice. Crop sown on 30th October produced significantly higher values of growth parameters, yield attributes (115 productive tillers per meter row length, no. of grains per spike- 37 and test weight -46.90) and yield (grain yield- 4733 kg ha-1 and straw yield- 8368 kg ha-1). But it was statistically at par with 10th November sowing date. Grain protein content, hectoliter weight and bold grains percentage decreased significantly with delay in sowing while malt content percentage was recorded significantly higher (89.53%) in 10th December date of sowing. Among the cultivars DWRUB 52 produced significantly higher grain yield (4516 kg ha-1) and quality attributes like malt content (86.25%) than other cultivars

Stability analysis for grain yield and some quality traits in bread wheat (Triticum aestivum L.

The present study was conducted to assess the genetic diversity and stability for grain yield (GY), 1000- grain weight (TGW), protein content (PC), grain iron (Fe) and grain zinc (Zn) concentration under three varied environmental locations using 28 diverse wheat genotypes (including three checks i.e., WH1105, DPW621-50, and HD2967 ). The material was sown at three locations during Rabi 2015-2016. Pooled analysis of variance revealed highly significant variance due to environments for all the traits studied indicating differential response of the genotypes. The genotype BWL 3584 exhibited stable performance across the environments for grain yield and grain zinc concentration under un-favorable environment also shows potential for high grain yield and high grain zinc concentration. After further confirmation, genotype BWL 3584 could be utilized as potential donor in hybridization programme to improve grain yield and grain zinc concentration. Further, genotype SABW 225 showed consistent performance across the environments for TGW and PC content. Whereas, PBW 744 was found to be suitable for GY (6142 kg/ha), coupled with PC (12.09%) and Zn (52.18ppm) across the locations followed by PBW 725 (6094, 12.26 and 46.96) and BWL 3584 (5219, 12.63 and 50.23) GY, PC and Grain Zn, respectively)and BWL 3584 (5219, 12.63 and 50.23) could be utilized as a donor in routine breeding programme to improve grain yield and quality traits in bread wheat

Magnon-magnon interactions in the Spin-Peierls compound CuGeO_3

In a magnetic substance the gap in the Raman spectrum, Delta_R, is approximatively twice the value of the neutron scattering gap, Delta_S, if the the magnetic excitations (magnons) are only weakly interacting. But for CuGeO_3 the experimentally observed ratio Delta_R/Delta_S is approximatively 1.49-1.78, indicating attractive magnon-magnon interactions in the quasi-1D Spin-Peierls compound CuGe_3. We present numerical estimates for Delta_R/Delta_S from exact diagonalization studies for finite chains and find agreement with experiment for intermediate values of the frustration parameter alpha. An analysis of the numerical Raman intensity leads us to postulate a continuum of two-magnon bound states in the Spin-Peierls phase. We discuss in detail the numerical method used, the dependence of the results on the model parameters and a novel matrix-element effect due to the dimerization of the Raman-operator in the Spin-Peierls phase.Comment: submitted to PRB, Phys. Rev. B, in pres

Occurrence of elevated nitrate in groundwaters of Krishna delta, India

Nitrate concentrations were measured in the groundwater samples of Krishna delta, India. The results indicate a large variation of nitrate from 10 - 135 mg/l. In 79 groundwater samples, about 39% shows high nitrate contents (>50 mg/l), which is more than the permissible limits in drinking water. In north Krishna delta 49% and in south Krishna delta 26% water samples were found to exceed the permissible limits. This study indicates that groundwater of north Krishna delta is more polluted than south. Nitrate pollution level is found more in dug wells compared to hand pumps/bore wells. In this region 49% dug wells and 31% hand pumps have exceeded the desirable limits. The possible sources for the high nitrate level in groundwater were identified as excessive utilization of nitrogenous fertilizers for agricultural purposes.Key words: Nitrate pollution, groundwater, Krishna delta, India