Investigations on Fe3+ doped polyvinyl alcohol films with and without gamma (γ)-irradiation

This paper deals with the preparation of pure and ferric chloride (FeCl3) doped polyvinyl alcohol (PVA) films by solution casting method. Optical and electrical properties were systematically investigated. We have found the decrease in optical band gap energy of PVA films on doping FeCl3. The optical band gap energy values in the present work are found to be 3.10 eV for pure PVA, 2 eV for PVA:Fe3+ (5 mol%), 1.91 eV for PVA:Fe3+(15 mol%) and 1.8 eV for PVA:Fe3+(25 mol%). Direct current electrical conductivity (σ) of pure, FeCl3 doped PVA films in the temperature range 70–127 °C has been studied. At 387 K dc electrical conductivity of pure PVA film is 5.5795 μ Ω−1 cm−1, PVA:Fe3+ (5 mol%) film is 10.0936 μ Ω−1 cm−1 and γ-Irradiated PVA:Fe3+ (5 mol%) film for 900 CGY/min is 22.1950 μ Ω−1 cm−1. The result reveals the enhancement of the electrical conductivity with γ-irradiation. FT-IR study signifies the intermolecular hydrogen bonding between Fe3+ ions of FeCl3 with OH group of PVA

Thermoluminescence, optical absorption and ESR studies in (KCl)1-x(KBr)x mixed alkali halide crystals doped with gold

Mixed crystals of KCl–KBr of different compositions were grown with Czochralski technique. Crystals were doped with gold. Both the undoped and gold doped crystals were γ γ -irradiated using 60 Co 60 Co source. All the irradiated samples were subjected to thermoluminescence, optical absorption and ESR studies. The present study shows the composition dependence of the parameters and enhancement in the luminescence intensity as well as the absorption coefficient with gold doping. Non-linear variation of color center peak position and half band width of F-center with composition has been observed. The results of the above studies are presented in this paper

Temperature dependence of pure quadrupole resonance of 35Cl in α-CH2ClCOOH

Measurements of the pure quadrupole resonance frequency of 35Cl in CH2ClCOOH have been made over a wide range of temperature (77K to 300K). Two resonance lines due to chemically inequivalent sites have been observed throughout the above temperature range

Modelling the hydromechanical response in the vicinity of the Koyna reservoir (India): results for the initial filling period

International audienceThe seismic activity in the Koyna area is clearly related to the water impoundment of the Koyna dam in 1962, and has reached a remarkable level with the occurrence of a major event of magnitude 6.3 in 1967 December 10. We present a homogeneous poroelastic model based on analysis of the first eight years of seismicity, which aims to link the water-level fluctuations of the reservoir with the seismicity. Starting from a discretized lake,we calculate the stress field resulting from the water-level fluctuations and the pore pressure changes due to the undrained and the diffusive responses of the medium. Then, we compare the Coulomb stress variations with a set of relocated seismic events. We find that more than 80 per cent of the relocated events before the M6.3 event are well described by this poroelastic model, leading us to derive a suitable diffusivity cp = 0.2m2 s-1. Then, we model the response of the system after the M6.3 event of 1967 December 10, by comparing the variation of the Coulomb stress field with the spatio-temporal characteristics of the relocated post-seismic events and the decay of aftershocks with time. We find that compared to before the main event a tenfold increase in hydraulic diffusivity is required to satisfactorily describe the aftershock decay with the appropriate Omori exponent. Although this increase in diffusivity may be physically related to the main shock we also note that events later than 9 months after the main shock are not well explained. We therefore propose an alternative hydrological model, which involves two compartments of contrasting diffusivities

Documents matches "Temperature- and pressure-dependent Study of 35Cl NQR Frequency and Spin Lattice Relaxation Time in 2,3-dichloroanisole

The temperature and pressure dependence of 35Cl NQR frequency and spin lattice relaxation time (T1) were investigated in 2,3-dichloroanisole. Two NQR signals were observed throughout the temperature and pressure range studied. T1 were measured in the temperature range from 77 to 300 K and from atmospheric pressure to 5 kbar. Relaxation was found to be due to the torsional motion of the molecule and also reorientation of motion of the CH3 group. T1 versus temperature data were analyzed on the basis of Woessner and Gutowsky model, and the activation energy for the reorientation of the CH3 group was estimated. The temperature dependence of the average torsional lifetimes of the molecules and the transition probabilities were also obtained.NQR frequency shows a nonlinear behavior with pressure, indicating both dynamic and static effects of pressure. The pressure coefficients were observed to be positive for both the lines. A thermodynamic analysis of the data was carried out to determine the constant volume temperature coefficients of the NQR frequency. The variation of spin lattice time with pressure was very small, showing that the relaxation is mainly due to the torsional motions of the molecules

Electrical Conductivity and Dielectric Properties of KH2PO4 Crystals Modified with KBr and NaBr

Pure KH2PO4 (KDP) and KDP crystals containing KBr and NaBr with/without gold doping were grown by slow evaporation technique. All the grown crystals were γ- irradiated using 60Co source. Electrical conductivity measurements were carried out perpendicular to the unique direction before and after γ-irradiation. The present measurement shows that the conductivity of KDP crystals increases with the addition of KBr and NaBr and with gold-doping as well as temperature. Computed values of activation energies from the conductivity measurements are given. Dielectric constant is measured as a function of frequency. Study confirms the contribution of space charge polarization. © 2005 IACS

Evaluation of morbidity and epidemiology of two wheelers accidents in central India

Background: In the developing world, the current trends in population growth, industrialization and urbanization are putting heavy pressure on the transport network in general and on road system in particular. Some of the unwanted side effects of this growing traffic, such as congestion and noise pollution are immediately obvious to the individual. But others, such as the growing number of fatal and non-fatal injuries from Road Traffic Accidents (RTAs), are apparent only through aggregated statistics. These data reflects serious and growing problem, with absolute fatality and casualty figures are rapidly rising in the majority of developing nations and with morbidity and mortality rates considerably higher than in the developed world. The alarming increase in morbidity and mortality owing to road traffic accidents over the past decades is a matter of great concern globally. In this study we have done evaluation of morbidity and epidemiology of two wheelers (two wheeler vehicles are those vehicle which runs on fuel e.g. Motorcycle) accidents in Central India.Methods: There were about 1514 patients who came to Accident and Emergency department of Acharya Vinobha Bhave Hospital from September 2014 to August 2015 with history of RTA, out of which 100 cases of road traffic accidents involving two wheelers were interviewed, using interview technique as tool for data collection.Results: Out of 100 cases of road traffic accidents involving two wheelers 84 were male and 16 were female patients. Among 100 patients 46% had trauma by skidding of bike. Accidents took place at early morning (17%), afternoon (37%) and evening (31%) and night (15%) time. A number of patients (41%) were under influence of alcohol making it a major reason of trauma. Seventy five percent of the patients were driving the vehicle. In 25% of cases, patients were the pillion riders. In our study out of 100 patients, 99 were not wearing a helmet except for 1 patient. Among 100 patients, 54 were having orthopaedic injuries. Among the orthopaedic injuries, lower limb injuries were 46% and upper limb were 45%.Conclusions: In our study we concluded that most of the accidents on two wheelers were of younger adults with predominance of male population and mostly occurred at daytime. Most of the drivers were under the influence of alcohol and were prone to accidents. The problems with two – wheelers accidents were condition of road, alcohol influence, and condition of vehicle.Keywords: Road Traffic Accidents, Two – wheelers, Central India, Morbidity,  Epidemiolog

Management of root-knot nematode Meloidogyne incognita infesting turmeric (Curcuma longa) under coconut (Cocos nucifera) cropping system

Field experiments were conducted during 2018–19, 2019–20 and 2020–21 at ICAR-Central Plantation Crops Research Institute, Kasaragod, Kerala for assessment of biocontrol fungi for the management of root-knot nematode (RKN), Meloidogyne incognita damaging turmeric (Cucuma longa L.) (cv. IISR-Prathibha) under coconut (Cocos nucifera L.) cropping system. Treatments included talc-based formulations of Trichoderma harzianum (ICAR- Indian Institute of Spices Research (IISR), Kerala and ICAR-Central Plantation Crops Research Institute (CPCRI), Kerala isolates) and Pochonia chlamydosporia (ICAR-Indian Institute of Spices Research, Kerala isolate), neem cake, marigold and carbosulfan 25 ec (standard check). Talc-based formulations were applied at 50 g/bed, neem cake @1 kg/bed at pre-monsoon and post-monsoon, marigold @30 plants/bed compared with untreated and standard check carbosulfan 25 ec @5 litre/bed at pre-monsoon and post-monsoon against M. incognita. Maximum reduction of RKN in the soil, as well as root, was achieved by either P. chlamydosporia (74 and 86%, respectively) or carbosulfan (67 and 87%, respectively) over the control. A number of the tillers (3.75/plant) for P. chlamydosporia and (3.23/ plant) for carbosulfan were recorded more in comparison to control (1.42/plant). The findings demonstrated that P. chlamydosporia (ICAR-Indian Institute of Spices Research) is a promising alternative to synthetic nematicides for the management of M. incognita due to its high antagonistic and good plant growth promotion activities. However, large scale field trials on these promising fungal biocontrol agents can be considered for evaluation in relation to the management of RKN under field conditions for confirmation