9 research outputs found
Water Consumption, Yield, and Total Dry Matter of Drip-Irrigated Cabbage Grown at Various Water Application Levels
In Ghana's coastal savannah climate, the lack of sufficient water during the dry season limits cabbage production. Using a small-scale drip irrigation system, two cabbage varieties—K-K Cross and Oxylus—were grown in a coastal Savannah environment. The irrigation levels were set at40,55,70,85, and 100% of the needed water. The two types of cabbage were assigned to the sub-plots, and the main plot consisted of the applied water levels. The experiment was conducted in three replicates using the split-plot design. The study aims to estimate the actual evapotranspiration (AET) for consumptive use for two cabbage cultivars grown using the family drip irrigation technology at varying applied water levels, as well as to calculate the total fresh matter yield, marketable fresh matter yield, and total dry matter yield of the two drip-irrigated cultivars at varying applied water levels. The overall trend showed that the productivity and water consumption of Oxylus and K-K Cross decreased as applied water levels decreased. The highest values of total dry matter and fresh yield were obtained at 100% of applied water, and these differences were significantly (P≤0.01) different from corresponding values obtained at 40%, 55%, 70%, and 85% of applied water. Thus, the study's findings highlighted the necessity of preserving sufficient soil moisture to improve productivity and the efficient use of water
Study of molecular reorientation and quantum rotational tunneling in tetramethylammonium selenate by 1H NMR
Thermodynamic Properties of Spin Ladders with Cyclic Exchange
By high temperature series expansion and exact complete diagonalization the
magnetic susceptibility chi(T) and the specific heat C(T) of a two-leg S=1/2
ladder with cyclic (4-spin) exchange are computed. Both methods yield
convincing results for not too small temperatures. We find that a small amount
of cyclic exchange influences the thermodynamical properties significantly. Our
results can serve as reliable basis for an efficient analysis of experimental
dataComment: 6 pages, 7 figure
Surface plasmon–exciton transition in ultra-thin silver and silver iodide films
Abstract Silver thin films in the thickness range 2–10 nm produced by thermal evaporation onto glass substrates were systematically iodized and carefully characterized by X-ray diffraction, atomic force microscopy (AFM) and optical absorption spectroscopy. While the uniodized films are X-ray amorphous in keeping with their quasi-continuous nature and 2D islanded structure, briefly iodized films showed characteristic beta AgI structure. Most interestingly, AFM of Ag films revealed uniform triangle-shaped embryos whose shape does not change appreciably upon iodization. Optical absorption spectra of uniodized Ag films show intense surface plasmon resonance (SPR) features with maxima at 440, 484 and 498 nm for the films of thicknesses 2, 5 and 10 nm, respectively, with 5 nm films showing properties characteristic of optimally matched dielectric and electronic properties of the substrate and sample, respectively. Finally, an interesting and unique SPR–exciton phase transition is observed as the ultra-thin films are progressively iodized. These Ag and AgI films could be promising candidates for plasmonic and nanophotonic applications
A method for broken bar fault diagnosis in three phase induction motor drive system using Artificial Neural Networks
This paper presents a high accuracy detection of Broken Rotor Bar (BRB) fault by Artificial Neural Network (ANN) through advanced signal processing tool as Hilbert Transform (HT) where three phase Induction Motor Drives (IMD) is operated under Direct Torque Control (DTC) topology with steady state. The major significance of all diagnostic methods is, need information about the characteristic?s frequencies and amplitude. The diagnosing of machine fault requires the spectrum into isolated various frequency components. The Discrete Fourier Transform (DFT) cannot produce good output at low slip. So, in this paper ANN and HT are proposed. DTC method is efficient technique in industrial drives with variable torque applications. The stator current envelope can be formed by HT. Then samples of amplitude and side band frequency are given as ANN inputs. In order to diagnose the quantity of BRB in IM, the findings are qualified and checked to the minimal Mean Square Error (MSE).Scopu