The longwall mining is considered to be the best coal mining practices due to vast recovery of coal over other forms of underground as well as opencast mining methods. But the actual scenario is ...quite opposite in India where productivity form of the longwall mines lags far behind than the desired level. Irregular caving and sudden rock bursts, which are very hazardous for mine workers and equipment. Usually these are major problem faced by bulk of Indian longwall faces and which are due to the presence of thick sandstone beds as overlying strata. Thus to keep an eye on the rock bursts, it is very necessary to monitor the stressed zones in the hanging overlying strata above and behind the panel. Earlier Correlation Integral ‘C’ and Correlation Fractal Dimension ‘Dc’ has been very helpful in monitoring the stressed zones for several great earthquakes in past. Following the same way, in the present study we have used the mine-induced microseismic data obtained from the retreating longwall panel using various monitoring instruments to calculate the Correlation Fractal Dimension ‘Dc’ for monitoring the stress levels and fractures in the overlying strata and also for spatio-temporal forecasting of roof-falls. The variation of blast charge size with Fractal Dimension is also studied. The use of Fractal Dimension has been very effective in obtaining the precursory signatures for roof-fall, thus ensuring safety in the mines.
•Identification of stressed zones using Fractal signatures.•Prediction of roof-fall both within and behind the panel.•Spatio-temporal forecasting of roof-fall using Fractal Dimension.•Estimation of blast charge size using Fractal Dimension.•Fracture monitoring in the overlying strata.
Paste backfilling is an incipient underground mine backfill technology in India. It facilitates maximum use of mill tailings with enhanced stability of the underground workings and minimises ...rehandling of water, as well as provides bulk disposal of mining solid waste. Binder type and dosage plays an important role in paste backfill performance. This paper highlights environmentally friendly utilisation of solid wastes like lead–zinc mill tailings and lead–zinc smelter fuming furnace slag (FFS) as paste backfilling for an underground metalliferous mine. Various experiments were conducted to study the effect of use of FFS as a fractional replacement for ordinary portland cement (OPC) in paste backfilling. The physico-chemical properties of both the lead–zinc mill tailings and fuming furnace slag (FFS) have been examined. In the first set of experiments, raw slag (FFS) was used for paste backfill preparation and experimentation for uniaxial compressive strength (UCS) development, whereas in the second set of experiments, FFS was crushed to -75 μm (80 wt%) and used for the study. Multiple regression analysis of strength development was also conducted up to fifth order. The regression analysis is in accordance with the strength development and justifies the significance of OPC, crushed fuming furnace slag (CFFS) and waste chemistry on the strength gain with curing time. Use of crushed fuming furnace slag as OPC replacement in paste backfill showed encouraging results of strength development in contrast to raw FFS. Also, the economic analysis revealed that the paste backfilling cost per tonne reduced significantly with slag replacement in the binder phase.
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•Synthesis of stable AgNPs using leaves of Desmodium gangeticum was demonstrated.•The synthesized nanoparticles solution was stable for more than four months.•The AgNPs were spherical ...in shape with moderate variation in particle sizes.•The synthesized AgNPs exhibited antimicrobial activity due to synergistic effects.
An aqueous leaf extract of Desmodium gangeticum was employed to synthesize silver nano particles. Rapid formation of stable silver nanoparticles were observed on exposure of the aqueous leaf extract with solution of silver nitrate. The silver nanoparticles were characterized by UV–visible spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis and transmission electron microscopy (TEM), and Fourier Transform Infra-Red spectroscopy (FTIR) UV–visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), transmission electron microscopy (TEM), and Fourier Transform Infra-Red spectroscopy (FTIR). UV–visible spectrum of the aqueous medium peaked at 450nm corresponding to the plasmon absorbance of silver nanoparticles. SEM analysis revealed the spherical shape of the particles with sizes ranging from 18 to 39nm and the EDAX spectrum confirmed the presence of silver along with other elements in the plant metabolite. Further, these biologically synthesized nanoparticles were found to be highly toxic against pathogenic bacteria Escherichia coli, thus implying significance of the present study in production of biomedical products.
Local implementation of non-local quantum gates is necessary in a distributed quantum computer. Here, we demonstrate the non-local implementation of controlled-unitary quantum gates proposed by ...Eisert et al. (Phys Rev A 62:052317,
2000
) using the five-qubit IBM quantum computer. We verify the fidelity and accuracy of the implementation through the techniques of quantum state and process tomographies.
OBJECTIVE: The objective of the study was to assess the efficacy and safety profiles of combined treatment of prednisolone with thalidomide (Gr-A) and prednisolone with clofazimine (Gr. B) in ...patients with erythema nodosum leprosum (ENL) or type 2 lepra reactions.
MATERIALS AND METHODS: Efficacy of both regimens was assessed on the basis of clinical recovery of recurrent ENL measured by reaction severity score (RSS), Visual Analog Scale (VAS), and recurrence of type 2 lepra reaction. The causality assessment of adverse drug reactions was done using the WHO UMC causality assessment scale.
RESULTS: The average age of patients with recurrent ENL was 42.8 years (male) and 51.8yrs (female) and had mean duration of leprosy and recurrent ENL 2.4 years and 2.09 years, respectively. 80% of nonrecurrence was observed in Gr-A versus 66% in Gr-B. Significant (P < 0.05) lower RSS and VAS was found in both the treatment groups as compared to pretreatment value. The reduction in RSS and VAS was statistically significant (P < 0.05) in Gr-A compared to Gr-B treatment.
CONCLUSION: Thalidomide combination with steroid was found to be more efficacious than clofazimine combination with steroid in the treatment of ENL both the treatment regimens showed few tolerable side effects. Improved strategies for the treatment and management of these reactions need to be developed.
Goldspot mullet, Liza parsia is a commercially important fish of South East Asia, where its farming depends on wild seed resources due to unavailability of hatchery technology. It, therefore, is ...important to understand the annual reproductive cycle of female L. parsia in captivity. In this study, adult male and female L. parsia (body weight ranges: 45–90 g; total length ranges: 100–125 mm, age >1 year) were collected from the wild and reared in a brackishwater pond. Thereafter, fish were randomly sampled at monthly intervals to measure the hepatosomatic index (HSI), gonadosomatic index (GSI), levels of serum steroids (testosterone, T; 17β-estradiol, E2 and 17α-hydroxyprogesterone, 17-OHP), and oocyte growth. Results exhibited that female L. parsia undergoes six different maturation stages, namely I (oocyte diameter, OD: <100 µm), II (OD: 100–350 µm), III (OD: 350–400 µm), IV (vitellogenic oocyte, OD: 400–450 µm), V (ripe oocyte, OD: 450–550 µm) and VI (atretic oocyte, OD: 60–150 µm), with synchronous oocyte development. The highest (P < 0.05) HSI (1.96 ± 0.24) and GSI (12.01 ± 0.73) were recorded in December and January, respectively. Concentration of E2 gradually increased from August and reached its peak (807.67 ± 25.98 pg mL−1, P < 0.05) in December. The level of 17-OHP (85.87 ± 0.91 pg mL−1) was at its peak during the normal spawning month (January) (P < 0.05). Overall, the results indicated that L. parsia attains maturity in brackishwater pond, which is consistent with previous observations, and altogether provide the basis to develop a breeding technology in captivity through hormonal and environmental manipulations.
•Liza parsia collected from wild attain sexual maturity in brackishwater pond.•Annual reproductive cycle in captivity showed peak of maturation from January to March.•L. parsia has synchronous type of oocyte development.•Serum E2 level gradually increased from August and reached its peak in December.
The India-based Neutrino Observatory (INO) is a project aimed at building a large underground laboratory to explore the Earth's mater effects on the atmospheric neutrinos in multi-GeV range. INO will ...host a 50 kton magnetized iron calorimeter detector (ICAL) in which Resistive Plate Chambers(RPCs) will be the active detector elements. In ICAL, 28,800 glass RPCs of 2m×2 m size will be operated in the avalanche mode. A small variation in the compositions of ionizing gaseous medium in the RPC affects its performance. Study of the charge distribution of the RPC at different gas compositions is necessary to optimize the gas mixture. An RPC made with glass plates of dimension 30cm×30 cm was operated in avalanche mode with a gas mixture of C2H2F4/iC4H10/SF6. We have studied the performance of these RPCs at the same ambient conditions. The percentages of the iC4H10 or SF6 were varied and its effect on the performance of RPC were studied. The study of the charge distribution and time resolution of the RPC signals at different gas compositions is presented in this paper.
•Submicron size strontium doped BZT ceramics were prepared by high energy ball milling.•Structural analysis was done by Reitveld refinement and Raman analysis.•Decrement in transition temperature and ...increment in diffusivity is observed with doping.•Remnant polarization decreases and coercive filed increases with doping.•Optical study was done by UV–vis spectroscopy and the optical band gap increases with doping.
Strontium modified barium zirconium titanate with general formula Ba1−xSrxZr0.05Ti0.95O3 ceramics have been prepared by solid state and high energy ball milling technique. The X-ray diffraction and Rietveld refinement studies show that all the compositions have single phase symmetry. The composition BaZr0.05Ti0.95O3 shows orthorhombic symmetric with space group Amm2. The structure changes from orthorhombic to tetragonal with strontium doping up to x=0.3 and with further addition, changes to cubic. The scanning electron micrographs show that the grain size decreases with increase in strontium content. The temperature dependent dielectric behavior shows three phase transition in the parent material which merges with an increase in Sr content. The transition temperature and dielectric constant decreases with an increase in Sr concentration. The phase transition becomes more diffused with increment in doping concentration. The ferroelectric behavior of the ceramics is studied by the hysteresis loop. The optical behavior is studied by the UV–visible spectroscopy and found that the optical band gap increases with Sr concentration.
Surface disposal of mill tailings and fly ash is a major concern for many countries, as it pollutes the environment including air, water, and soil. Paste backfilling is an emerging mine backfilling ...technique, wherein the industrial wastes such as mill tailings, fly ash and blast furnace slag are backfilled inside the stopes. This study examines the physico-chemical characteristics of lead–zinc mill tailings, fly ash and their mixtures for their possible utilization in paste backfilling in underground metalliferous mines. Three different mill tailing–fly ash mixtures, viz., 95:5, 92:8 and 90:10 (wt%), have been considered. The chemical, morphological and mineralogical compositions are analyzed by XRF, SEM and XRD. The morphological analysis revealed that the mill tailings are irregular in shape and fly ash particles are almost spherical in nature. The filling of inter-particle spaces of irregular mill tailings with spherical fly ash and finer mill tailings (− 20 µm) particles will enhance the rheology of mill tailing–fly ash mix paste backfill. Chemically, the lead–zinc mill tailings is enriched in SiO
2
, CaO, Fe
2
O
3
, and Al
2
O
3
, whereas fly ash is mainly composed of SiO
2
and Al
2
O
3
with small amounts of Fe
2
O
3
, CaO, K
2
O, TiO
2
, MgO, SO
3
, Na
2
O, and P
2
O
5
. The XRD analysis revealed that the lead–zinc mill tailings mainly contain quartz, pyrite, dolomite, hematite and calcite, while fly ash contains quartz, mullite, kaolinite and hematite. This study proved that lead–zinc mill tailings and fly ash together can be suitably used for paste backfilling in underground metalliferous mines.
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