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A rise in infections caused by methicillin- and vancomycin-resistant Staphylococcus aureus is an increasing global health concern that causes boosting illness and death. The growing problem of drug resistance has emphasized the need to discover and develop new antibacterial agents that work through different mechanisms. To address this issue and create prospective antibacterial drugs, numerous chalcone derivatives of thiazolidine-2,4-dione have been designed, synthesized, and evaluated against three bacterial strains and one fungal strain. Compounds 7a, 7h, and 7k were found to selectively inhibit S. aureus at a concentration of 25 μg/mL but were inactive toward gram-negative bacteria. [ABSTRACT FROM AUTHOR]

The article provides a long-term trend analysis of the Kesinga catchment daily gridded rainfall at a (0.25° × 0.25°) high spatial resolution from 1901 to 2020 (120 years). The trend in seasonal and annual rainfall was detected using rank-based nonparametric statistical tests, namely Spearman's rho and Mann-Kendall test, which are used for detecting monotonic trends in time series data at the 5% significant level, smoothing curve, Sen's slope test, and a plot of innovative trend analysis. The results showed that statistically significant trends had a pattern with both positive (increasing) and negative (decreasing) trends, with positive and negative trends evident in the winter and negative trends shown in the monsoon, PREMON, and annual seasons. The middle of the study area revealed the highest negative trend, and the lower Kesinga catchment showed the lowest negative annual rainfall trend. In the entire Kesinga catchment, the seasonal data and annual rainfall both showed statistically significant and non-significant patterns. Consistently, the MK and SR tests were both conducted at the validated significance level. In various contexts, the statistically significant massive trend that has occurred was negative (70%). If the current pattern continues in the future, there will be a scarcity of water and more strain on the control of water resources at the given grids in corresponding temporal scales. [ABSTRACT FROM AUTHOR]

A novel series of triazole-quinazoline hybrid molecules was synthesized and characterized by spectral analyses. The H37 RV strain was used to test the newly synthesised compounds for antitubercular efficacy against Mycobacterium tuberculosis. Some of the synthesized compounds were effective compared with standard pyrazinamide at a concentration of 3.12 μg/mL. Additionally, molecular docking investigations were conducted on all synthesized compounds against the M. tuberculosis InhA protein, which is attenuated by the PT70 X-ray crystal structure, PDB ID: 2X22. Two compounds were revealed the best against 2X22, with Autodock scores of –9.13 and –8.59, respectively. To further investigate the teratogenicity of the synthesized compounds, zebrafish larvae were employed. At a concentration of 100 μM, some compounds showed no signs of abnormality. [ABSTRACT FROM AUTHOR]

Investigation of radon transport processes in the earth's crust due to the changes in the geophysical processes is an important area. The present paper examines the estimation of uncertain bounds for the radon concentration in the earth's crust to identify the anomaly behavior of radon data. However, it is necessary to investigate the role of uncertainty involved in the governing parameters, which are estimated from experimental measurements. Accordingly, the imprecision of the model parameters is addressed as a fuzzy variable and the membership function of each such fuzzy variable is expressed in the form of a triangular fuzzy number. Further, a fuzzy band of the radon concentration is estimated to predict the anomaly behavior of radon in the earth's crust. [ABSTRACT FROM AUTHOR]

We probe roles of blackbody friction forces (BBFFs) in slowing down alkali atoms, from Li through Fr, for high-precision measurements. An atom can encounter BBFF caused by the blackbody. We probe roles of blackbody friction radiations of the stray electromagnetic fields present in experimental set-up and other metallic shielding during measurements. Strengths of BBFFs on the alkali atoms are estimated by integrating complex parts of dynamic polarizabilities of atoms over a wide range of frequency. Slowdown times of moving atoms due to these friction forces are analysed as a function of temperature. The results are determined by both including and excluding nonresonant contributions in the polarizabilities of atomic states. This shows that inclusion of nonresonant contributions affects the slowdown time of atoms significantly at low temperatures. Our study will be useful in accounting for these slowdown times in the ongoing and future high-precision experiments involving alkali atoms. [ABSTRACT FROM AUTHOR]

The present study demonstrates the spatial analysis and mapping of fish and different measures of environmental parameters and fish diversity of Pong reservoir, Himachal Pradesh, using Kriging spatial interpolation methods for geographical information system mapping. Seasonal data on environmental parameters, potential fish habitat and fish diversity was collected from lentic (dam), lentic (reservoir), transitional and lotic zone of the reservoir.. Important environmental parameters like water temperature, dissolved oxygen, electrical conductivity, water depth and transparency showed variations across the different zones of the reservoir. The sediment of the reservoir was sandy clay loam in nature as per texture analysis. Fish species richness, Shannon index and evenness index showed a similarity of the lotic and lentic (reservoir) zones of the reservoir. Six potential fish breeding grounds were identified in the reservoir indicating high conservation significance. The analysis of data showed a declining trend in fish production from 456.9 tonnes during the decade 1976–1987 to 347.91 tonnes during 2009–2020. The factors like anthropogenic climate change, predation of a stocked fish juvenile by water birds, undersized fish stocking and unscientific management are the probable reasons for the decreasing fish production. The spatial variation pattern of the water spread area, environmental parameters, fish catch and potential fish breeding grounds depicted in the GIS platform can be used as an important information base by the policy makers for fisheries management. The stocking of large size fish as a stocking material and adequate protection of the potential fish breeding grounds are the key advisories for the sustainable enhancement of fisheries as well as conservation. [ABSTRACT FROM AUTHOR]

Aerospace industries invest a significant amount of resources to meet one common goal, that is, to make the aircraft fly. To keep down its 'buy-to-fly' ratio, researchers have been working hard to introduce additive manufacturing (AM) technique for producing aerospace components. AM technologies are also now being used in major parts of an aircraft like fuel nozzles, turbofan blades, compressor-turbine blades, suspension wishbone, air ducts, etc., due to its just in time production with less complexity, direct tooling, and higher customer satisfaction with significant cost reduction including interior design. Nowadays, aerospace industries face problems meeting the deadline for delivering the aircraft components and replacement parts while maintaining certification standards. The wire arc additive manufacturing (WAAM) technique, one of the AM processes, can fabricate large metallic components with some reduction in lead time. WAAM process can build near net shape parts with high material deposition rate and efficiency while keeping the equipment and feedstock cost and material wastage minimal. This review paper summarizes the latest advancement on wire arc additive manufacturing of titanium and its alloy based on the aerospace application. Titanium and its alloys are used at a large scale in aircraft airframe structures and engine parts due to its high strength-to-weight ratio, excellent corrosion-resistant, high creep and fatigue resistance at an elevated temperature. It has been studied that the mechanical and metallographic properties of titanium and its alloy can be enhanced by using the WAAM process, and it is suited for aerospace applications. The paper will review the challenges like porosity, delamination, residual stress, crack propagation, anisotropic behavior, oxidation, etc., associated with the WAAM process on titanium alloys and propose recommendations for reducing the defects during the WAAM process. [ABSTRACT FROM AUTHOR]

The coal blends are used for both top and stamped charged coke oven batteries in Steel Plants which are consists of more than 5 to 7 individual coal sources depending upon the availability of coking coal. The blast furnace (BF) coke produced from the coke oven batteries are feed into both small and larger BF. The consistency of coke quality parameters is also a requirement for higher BF productivity and smooth functioning of BF. Coal preparation and coal blend quality parameters plays a very important role to get optimum quality of coke from a given blend. It is generally established that blend containing optimal reactive produces the coke of maximum strength. This studies, total 76 no's coal blends have been prepared and corresponding coke quality have been examined. Coal blend properties such as microfines (–0.5 mm), CSN, LTGK, ash, volatile matter (VM), total reactive content, MMR, fluidity and total dilatation acts as an important factor for coke making. The hot strength properties of coke CRI and (CSR: coke strength after reaction) also influence by MMR (mean maximum reflectance) of coal blend. From this study, it has been established to find out the optimum blend quality parameters for BF coke making. [ABSTRACT FROM AUTHOR]

In the present study, radon (222Rn), thoron (220Rn) exhalation rates, and the specific activities of 238U,232Th, and 40K of 75 soil samples collected from the surrounding area of a National Thermal Capital Power Station (NTPC) Dadri, are measured by using a continuous activity monitor, and high-resolution gamma-ray spectroscopy. Objective of the study is to find out if there is any excess radioactivity in the soil due to long term accumulation of fly ash on soil surface by comparing with data from adjoining region reported in literature. Also, to demonstrate the applicability of a radon exhalation-based model to quickly estimate the indoor radon concentration contributed by these soil samples if used for construction of houses. The mean values of radon mass and thorn surface exhalation rates are 50 ± 12 m Bq kg−1 h−1 and 6 ± 2 kBqm−2 h−1, respectively. The mean values with one standard deviation of 226Ra, 232Th, and 40K activities are 50 ± 6 Bq kg−1, 68 ± 10 Bq kg−1, and 650 ± 82 Bq kg−1, respectively. The average values of absorbed gamma dose rate and annual effective dose outdoors with one standard deviation for the adult population are found to be 91 ± 9 nGyh−1 and 0.11 ± 0.01 mSv, respectively. The average value of the radon emanation factor is found to be 0.13 ± 0.03. To the best of our knowledge, such kind of study has not been carried out in this region and is reported first time in this paper. [ABSTRACT FROM AUTHOR]

The core crust transition density and core crust transition pressure of neutron stars are analyzed with the thermodynamical approach using finite range effective interaction for two different splittings of exchange strength parameters. The role of density derivatives of symmetry energy on and are studied and it is found that reducing the effect of slope, the curvature of symmetry energy dominates the variation of transition density. The results are compared with various models quoted in the literature. [ABSTRACT FROM AUTHOR]

We study the variation of radon mass exhalation rate (Jm) and thoron surface exhalation rate (Js) with soil's porosity and moisture content using a scintillation based monitor-Smart RnDuo. Assessment were carried out in around 40 soil samples collected from four villages of East Khasi Hills district, Meghalaya, India. Results revealed that, both Jm and Js shows no convincing trend of variation with porosity, while with respect to moisture content, a sporadic increase is observed in the values of Jm and Js up to certain level, beyond which a decreasing trend is observed; accountable reasons are discussed in the manuscript. [ABSTRACT FROM AUTHOR]

Over the past two decades, lead-free piezoceramics have been developed aiming to replace toxic lead-bearing lead zirconate titanate (PZT). A large number of lead-free piezo systems were explored during this period as evidenced from the huge number of publications. At this juncture, it was felt necessary to publish a review article focusing on material systems and processes delivering high d33 in order to give direction to future research for its further improvement equivalent to or higher than the d33 level delivered by PZT. The important lead-free piezo systems under consideration are: modified barium titanates such as barium calcium titanate zirconate (BCTZ), barium calcium tin titanate (BCSnT), barium calcium hafnium titanate (BCHfT), and potassium sodium niobate (KNN). In this article, an effort has been made to review the high piezoelectric properties achieved on the above lead-free piezo systems explaining the reasons and mechanisms behind high piezo properties and possible future directions of the research for further enhancement of properties. [ABSTRACT FROM AUTHOR]

Dissolved radon (222Rn) in drinking water has been measured using SMART RnDuo, a continuous radon monitor. Water samples have been collected from hand pumps in surrounding regions of a Harduaganj thermal power plant (HTPP), Aligarh and Narora atomic power plant (NAPP), Bulandshahar situated in the Uttar Pradesh state of India. The 222Rn concentration ranges from 1.3 ± 0.3 to 17 ± 1 Bql−1 around HTPP, and from 2.4 ± 0.5 to 17 ± 1 Bql−1 around NAPP. The measured radon concentration in all collected samples lies well below the limit of 100 Bql−1as set by the World Health Organization. The total annual effective dose due to waterborne 222Rn inhalation and ingestion varies from 6 ± 1 to 88 ± 4 µSvy−1 around HTPP and from 6 ± 1 to 42 ± 3 µSvy−1 around NAPP. The total annual effective dose around both the plants is also well below the safe limit of 100 μSvy−1 recommended by the European Commission and World Health Organization. The radiation dose to the lungs, stomach, and liver are also calculated in the regions under study. [ABSTRACT FROM AUTHOR]

Indoor radon, thoron, and their progeny concentrations were measured in Mokokchung district of Nagaland, India over three different seasons by using Direct Radon and Thoron Progeny Sensors and pinhole type radon-thoron discriminating dosimeters. The indoor radon and thoron concentrations were found to vary between 44 ± 6–75 ± 16 Bqm−3 and 25 ± 2–62 ± 49 Bqm−3 while their corresponding progeny concentrations varied between 3.2 ± 2.1–17.3 ± 8.7 Bqm−3 and 0.21 ± 0.06–1.49 ± 0.86 Bqm−3 respectively. Based on the study, it was found that the inhalation dose varied between 0.35 and 1.64 mSvy−1 and are within the recommended values as suggested by ICRP, 2018. The equilibrium factor (E.F) varied from 0.06 to 0.29 for indoor radon and 0.01 to 0.02 for indoor thoron. [ABSTRACT FROM AUTHOR]

This paper presents a causal relationship between thoron anomaly and earthquakes along the Indo-Burman subduction line. A 15 min cycle thoron data was generated at Mizoram University, Aizawl, Mizoram (India) between January, 2019 and December, 2019 for correlation with earthquakes. All earthquakes within 150 km from the monitoring station were correlated with an average precursory time of 7 ± 5 days. The empirical mode decomposition (EMD) based Hilbert–Huang transform (HHT) analysis shows that thoron anomaly of the monitoring station specifically responds to those earthquakes along the subduction line and the region was seismically active. [ABSTRACT FROM AUTHOR]

In the present work, Computational Fluid Dynamics (CFD) code has been used to simulate the behaviour of aerosols and decay products of 222Rn/220Rn in indoor environments. The code has been incorporated with simulation modules describing relevant physical processes governing the aerosol and decay product dynamics such as particle deposition, gravitational settling, thermophoresis, coagulation and size dependent attachment of decay products to aerosol. Subsequently, reliability and consistency of the CFD code has been evaluated and validated by comparing simulated results with analytical and simulation results of well-known cases reported in literature. Comparison showed a good agreement within ± 3.5%. [ABSTRACT FROM AUTHOR]

Coke is the most important raw material fed into the blast furnace. The blast furnace operation is linked with coke quality (cold and hot strength). Coke quality depends on the quality of incoming coal, its blending, pre-carbonization processing of coal blends. Heating and operational parameters of coke oven also have a significant effect on the coke quality. In a commercial coke oven, to monitor the effect of individual parameters on coke quality, other parameters are kept in close range so that their effect on the coke quality is minimal. This paper focuses on the effect of lowering the percentage of the microfines in coal blend and proper filling of ovens on the coke quality. Coal and coke quality parameters for a period of approximately two months were measured before and after implementation of the requisite steps. Based on the trial, the effect of microfines, % in the blend, and full charging in the oven were established. It was found that reduction in microfines by 6% i.e., from 48.6 to 42.5% with full charging in the ovens, led to significant improvement in CSR; some improvement trend in the Micum index was also observed. [ABSTRACT FROM AUTHOR]

Radiation exposure, an inescapable share of our everyday life, primarily arises from terrestrial or cosmic sources. A small fragment of the total dose is also contributed by our own bodies. Humans receive an average radiation of 2.4 mSv y−1 as natural background radiation. In the present study, an attempt to quantify groundwater radon-222 and indoor radon, thoron and their progeny was made using both active as well as passive techniques. Solid state nuclear track detectors (LR-115 type-II films) were employed for long-term passive measurements while as scintillation based radon monitor was used for active short-term measurements. [ABSTRACT FROM AUTHOR]

Coal is one of the main sources of energy in many parts of the world and has one of the largest reserves amongst all the nonrenewable energy sources. The effect of different size fractions of coal was analyzed by taking into account three types of coal namely, Australian Hard, prime coking coal (PCC) and medium coking coal (MCC). Various tests were helped in understanding the effect of different size fractions on coal properties. The bulk density of the master sample of all the three coals was found to be the average of the three size fractions i.e. +6 mm, +3.2 mm and –3.2 mm, respectively. The bulk density of all the three size fraction of coal decreased with decrease in size fractions. Also, a decrease in void spaces between the coal samples with decrease in size fraction was observed. Proximate analysis, crucible swelling number (CSN) and low temperature Gray King (LTGK) tests showed the values of the master sample to be an average of the three size fractions. There was a significant increase in volatile matter with decrease in size fraction. Generally, coal ash tends to retained in higher size fraction in coal. [ABSTRACT FROM AUTHOR]

The prolongation of coke oven service life beyond 40 years has become the norm in coke ovens abroad. Unfortunately, the average service life of a coke oven battery in India is only about 20 years. This anomaly needs to be rectified. Simultaneously, with the recent introduction of stringent environmental norms for Coke Oven Batteries, oven health gathers more criticality, since oven health and environmental pollution are directly related. A system was introduced at Rourkela Steel Plant (RSP) of SAIL for monitoring and diagnosing battery condition in terms of the health of refractory brickwork and the bracing system. The refractory brickwork condition was monitored through cross-leakage measurement of the whole battery as well as individual flues. The condition of the bracing system was monitored through thermal imaging of the oven top focusing on the vulnerable areas where the bracing system (cross and longitudinal tie rods) is in close proximity to heat sources. At the same time, feedback was taken from the on-line pusher ram current measurement system to validate the first two observations. Using these three observations, an integrated battery health monitoring system was developed. The system helped RSP in taking timely preventive repair actions and improving battery health. [ABSTRACT FROM AUTHOR]

The research is a maiden study aimed to assess the radioactivity in groundwater of Srinagar City using uranium and radon as proxies. In this study, 60 water samples were collected from various water sources that include bore wells, hand pumps and lakes of Srinagar City. Among them, 45 samples were taken from groundwater with depths ranging from 6 to − 126 m and the rest of the 15 samples were collected from surface sources like lakes, rivers and tap water. A gamma radiation survey of the area was carried out prior to collection of water samples, using a gamma radiation detector. A scintillation-based detector was utilized to measure radon, while as LED fluorimetry was employed to assess uranium in water samples. The average uranium concentration was found to be 2.63 μg L−1 with a maximum value of 15.28 μg L−1 which is less than the globally accepted permissible level of 30 µg L−1. 222Radon concentration varied from 0.2 to 38.5 Bq L−1 with an average value of 8.9 Bq L−1. The radon concentration in 19 groundwater samples (32% of total sites) exceeded the permissible limits of 11 Bq L−1 set by USEPA. This information could be of vital importance to health professionals in Kashmir who are researching on the incidence of lung cancers in the region given the fact that radon is the second leading cause of lung cancers after smoking worldwide. [ABSTRACT FROM AUTHOR]

Hot water springs and bore wells/hand-pumps were investigated to quantify radon and uranium levels in Rajouri area of the Pir Panjal. Scintillation-based radon monitor was employed for radon-222 detection while as LED Flourimetric technique was used to detect uranium-238 concentration. The radon-222 levels, found in the study area, are much higher than the limits prescribed by regulatory agencies like United States Environmental Protection Agency (USEPA). Some of the samples exceeded the allowed limits of 100 Bq L−1 set by World Health Organisation while none of the samples lied within the prescribed level of 11 Bq L−1 prescribe by USEPA. [ABSTRACT FROM AUTHOR]

This paper deals with a laminar swirling flow of a viscous fluid over a stretchable rotating disk. The classical flow over a solid disk is known as the Kármán flow problem. For the first time in the literature, the combined effects of both the Coriolis force and radial stretching on the stability of the Kármán swirling flow has been carried out. The numerical investigation has been performed by using the Chebyshev spectral method. It is discovered that surface stretching produces a destabilising effect on the Kármán flow. [ABSTRACT FROM AUTHOR]

In this study, an investigation has been carried out on the potential of radon, thoron and natural radioactive content by collecting soil samples from the Deccan land of Kolhapur district, India. The mean value of radon mass exhalation rates is 12.66 ± 1.07 mBqkg−1h−1 and mean thoron surface exhalation rate is 2300 ± 261 Bqm−2h−1. The mean value of Radon emanation factor is 5.18%. The mean activity concentrations of 238U, 232Th and 40K in the soil samples are 9.33 ± 0.45 Bqkg−1, 16.60 ± 0.77 Bqkg−1 and 66.15 ± 4.33 Bqkg−1 respectively and well below the value recommended by UNSCEAR 2000. [ABSTRACT FROM AUTHOR]

We report the method of tuning the thermal conductivity through the composition of multiwall carbon nanotube (MWCNT) dispersed ethylene glycol based nanofluids. The structure and properties of the MWCNTs were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Raman spectroscopy and thermogravimetric analysis. A parallel plate thermal conductivity (PPTC) set up was fabricated and used for measurement of thermal conductivity of the nanofluids. We have prepared ethylene glycol based nanofluids containing 0.05, 0.1, 0.15, 0.20, 0.25 and 0.35 wt% of MWCNTs. The thermal conductivities of these fluids were measured by keeping them between the two (parallel) plates, referred as the hot and the cold plates, of the sample holder in the PPTC apparatus. The lower plate was water-cooled and the upper plate was heated. The temperature of the hot plate was varied between 35 and 80 °C. The thermal conductivity of the fluids was calculated using the one-dimensional heat conduction equation. According to our observation, an efficient heat transfer occurs through the nanofluids with an optimum concentration of 0.20 wt% of CNTs. Our work demonstrates the importance of the composition of the nanofluids and their structural defects in heat transfer. [ABSTRACT FROM AUTHOR]

This paper describes radon mass exhalation rate ( J m) and thoron surface exhalation rate ( J s ) of 46 soil samples of district Faridabad, Southern Haryana, India. Scintillation detector based SMART RnDuo (AQTEK System, India) coupled with exhalation chamber was used. Outdoor gamma exposure rate was measured by GM counter based survey meter. J m of one sample and J s of 95% samples were found higher than world average values of 57 mBq kg−1 h−1 and 3600 Bq m−2 h−1 for J m and J s respectively reported by UNSCEAR 2000. No significant correlation was observed between radon/thoron exhalation rates with outdoor gamma exposure rate. [ABSTRACT FROM AUTHOR]

In the present study, indoor radon (222Rn), thoron (220Rn), radon progeny (214Po) and thoron progeny (212Po) activity concentration have been measured in a region around the National Capital Power Station, Dadri, Uttar Pradesh, India. The mean values of the 222Rn, 220Rn and their progeny in the studied region are found to be 22.1 ± 10.0 Bqm−3, 48.6 ± 13.5 Bqm−3, 8.8 ± 4.8 Bqm−3 and 0.49 ± 0.15Bqm−3 respectively. The annual inhalation dose estimated from the observed concentrations varies from 0.29 ± 0.04 to 2.06 ± 0.121 mSv with a mean value of 0.75 ± 0.32 mSv and is well within the reference level. It has also been observed that 212Po is a significant contributor (= 18.7%) to the total annual inhalation dose. Seasonal variations of 222Rn, 220Rn, and their progeny have also been reported. [ABSTRACT FROM AUTHOR]

The research paper presents implementation of a fuzzy rule and membership function-based fuzzy-aided PID controller for automatic generation control (AGC) in multiarea nonlinear power system. At the initial stage of this proposed work, a three-area nine-unit installed interconnected network is considered for developing different dynamic responses in response to AGC analysis. A modified approach named modified sine cosine algorithm (M-SCA) is proposed for tuning the gain parameters of the above-proposed fuzzy controller to produce close optimum gain values. The proposed modified algorithm is developed from its original sine cosine algorithm by improving and updating few equations which is capable of making the balance between exploration and exploitation levels of this algorithm and improving the updating quality of iteration. To impose supremacy of M-SCA technique, it is examined through convergence curves and its performance is compared with host sine cosine algorithm, genetic algorithm, and particle swarm optimization algorithm. For controller supremacy analysis, the performance of the proposed fuzzy-aided PID controller is compared with conventional I, PI, and PID controllers, and it has been revealed that proposed M-SCA-tuned fuzzy-aided PID controller exhibits better performances through different deviated responses for AGC analysis. To demonstrate most standard and supremacy of proposed approaches, finally these are tested through a five-area ten-unit system considering some physical nonlinear constraints like generation rate constraint, governor dead band, boiler dynamics and time delay. At the final observation level, the proposed fuzzy controller has gone through different sensitivity analyses with variation of different system parametric conditions and different load conditions. [ABSTRACT FROM AUTHOR]

This work reports on the application of a novel electric field-ionization setup for high-resolution laser spectroscopy measurements on bunched fast atomic beams in a collinear geometry. In combination with multi-step resonant excitation to Rydberg states using pulsed lasers, the field ionization technique demonstrates increased sensitivity for isotope separation and measurement of atomic parameters over previous non-resonant laser ionization methods. The setup was tested at the Collinear Resonance Ionization Spectroscopy experiment at ISOLDE-CERN to perform high-resolution measurements of transitions in the indium atom from the 5s 2 5d 2 D 5 / 2 and 5s 2 5d 2 D 3 / 2 states to 5s 2 n p 2 P and 5s 2 n f 2 F Rydberg states, up to a principal quantum number of n = 72 . The extracted Rydberg level energies were used to re-evaluate the ionization potential of the indium atom to be 46 , 670.107 (4) cm - 1 . The nuclear magnetic dipole and nuclear electric quadrupole hyperfine structure constants and level isotope shifts of the 5s 2 5d 2 D 5 / 2 and 5s 2 5d 2 D 3 / 2 states were determined for 113 , 115 In. The results are compared to calculations using relativistic coupled-cluster theory. A good agreement is found with the ionization potential and isotope shifts, while disagreement of hyperfine structure constants indicates an increased importance of electron correlations in these excited atomic states. With the aim of further increasing the detection sensitivity for measurements on exotic isotopes, a systematic study of the field-ionization arrangement implemented in the work was performed at the same time and an improved design was simulated and is presented. The improved design offers increased background suppression independent of the distance from field ionization to ion detection. [ABSTRACT FROM AUTHOR]

We report the growth of ammonium dihydrogen phosphate, NH4H2PO4 (ADP) single crystals by slow evaporation method and study of their dielectric property. Furthermore, we correlate the effect of the defects present in the single crystals with the dielectric and other related properties. After determination of the solubility limit of ADP salt in water at different temperatures, the seed crystals were nucleated and grown in the supersaturated solution, which was obtained by cooling the higher temperature saturated solution to room temperature. The phase purity of synthesized ADP crystals was studied by powder X-ray diffraction technique, on the finely ground seed crystals. The seed crystals of appropriate size were used for growth of large crystals and also used for dielectric measurements. Two single crystals with different concentrations of defects were used for the investigation of dielectric property at room temperature. The obtained dielectric data are discussed along with their representation in modulus and impedance formalism to understand the dielectric properties of these crystals. Overall, the low frequency Maxwell–Wagner interfacial polarization was found to increase due to the presence of defects in the ADP single crystals. [ABSTRACT FROM AUTHOR]

The coking behavior of coal is an important facet in utilization of coal in metallurgy and in other industries. The carbonization behavior of coal mainly depends on coal rank, petrographic composition, ultimate composition and rheology of coal. Coal petrography has become very useful technique for establishment between formulation of coal blend composition and coke quality prediction. It is generally established that blend containing optimal reactives produces the coke of maximum strength. The coking properties of coal not depend only on the macerals composition, but also on the way in which the macerals are distributed among one another, forming preferential associations called microlithotypes. The measurements of relative proportion of microlithotypes are called microlithotype analysis. In present work, distribution of macerals (microlithotype) in coal samples were studied and correlated with the coke quality. Beneficiation by wet method were carried out (only indigenous coal) by washing media of specific gravity 1.30 to 1.40 to achieve <10% ash level. Coal microlithotypes plays an important role on coke quality. Bi-maceral and tri-macerals microlithotype distribution (vitrinertite and duroclarite and clarodurite) in coal samples act as a vital role for coke quality. Inter-growth of internite within vitrinite macerals has also significant role on coke quality. Therefore, the combined analysis of maceral and microlithotype distribution is important for coke quality. Distribution of bi-maceral and tri- maceral in coal improved coke quality (M40 and M10 indices). The microlithotype distribution measurement by petrography analysis gave considerable correlations with M40, M10, Coke Reactivity Index (CRI) and Coke Strength after Reaction (CSR) parameters. It gave details the adaptability of Indian coke quality in favor of macerals assemblages in coal. [ABSTRACT FROM AUTHOR]

Computational fluid dynamics (CFD) has been used to simulate the distribution of indoor radon concentration in a naturally ventilated room. Finite volume method was employed in CFD code for the simulation of indoor radon. The simulation results were validated at 34 points in a matrix of two horizontal planes (y = 1.3 m and y = 2.1 m) using passive pinhole dosimeters and at six points using an active scintillation radon monitor. The CFD results were found to exhibit an excellent correlation with the measured values. It is concluded that CFD analysis is a powerful tool to visualize indoor radon distribution. [ABSTRACT FROM AUTHOR]

Radon, thoron and their progeny are responsible for more than 50% of the total ionizing radiation dose received by human population. In the present work, radon, thoron and their progeny concentration measurements have been carried out in 150 dwellings in different villages of Faridabad district of Haryana, India. Pin-holes based twin cup dosimeter containing LR-115 type-II film (solid state nuclear track detectors) has been used for the time-integrated passive measurement of radon and thoron concentrations. The dosimeters were deployed for three seasons each having 4 months of exposure period. For measurement of radon and thoron progeny concentration (EERC/EETC), deposition based direct radon/thoron progeny sensors (DRPS/DTPS) were deployed with dosimeters. Based on the gamma exposure rate in different villages during preliminary survey and type of houses available in the regions, numbers of dwellings of different categories have been selected. Radon, thoron and their progeny concentration and total annual effective inhalation dose were calculated and compared with the recommended limits by UNSCEAR, ICRP and WHO. [ABSTRACT FROM AUTHOR]

In the present work, radon concentrations were measured in surface and underground water samples in Faridabad District of Southern Haryana, India using an active radon monitor based on alpha scintillation technique and results have been inter-compared. The average radon concentration in the underground water samples was observed to be 4 times higher than in the surface water samples. The estimated annual effective dose varied from 5.7 to 58.5 μSvy−1 with an average of 24.2 μSvy−1 for underground water samples and 1.1 to 12.5 μSvy−1 with an average of 6.7 μSvy−1 for surface water samples. The estimated annual effective dose for both type of samples was found to be less than 0.1 mSvy−1, which is the safe limit as suggested by World Health Organisation and EU Council. [ABSTRACT FROM AUTHOR]

The quality of coke affects the performance of the blast furnace, factors affecting coke quality include coal properties, coal charge granulometry and carbonization conditions. The coke properties include the size analysis, cold strength (Micum Indices-M40, M10) and hot strength (Coke Reactivity Index-CRI, Coke Strength after Reaction-CSR) properties and structural properties such as coke structure and texture. Structural properties comprise the porosity, pore-cell wall thickness and pore sizes, while textures consist of the carbon forms in the coke. In present work, advanced method such as image analysis method was used to interpret coke microstructure. Conventional methods such as determination of coke porosity by measurement of real and apparent density and mercury porosimetry have a number of limitations. Coke size, magnification, number of image frames captured, process of pellet preparations and coke properties such as M40, M10, CRI and CSR (low, medium and high values) were taken as variables for experimental purposes. The coke structure parameters such as porosity, length, perimeter, breadth, roundness, pore-wall thickness and pore size distribution of the pores were determined by image analysis method. This method provided average porosity in addition to pore-wall thickness and pore-size distribution. The pore wall thickness measurement by image analysis method provided significant correlations with M40, CRI and CSR values. This explained the usability of image analysis for coke structure measurement. [ABSTRACT FROM AUTHOR]

Coke is the most important raw material fed into the blast furnace, in terms of its effect on blast furnace operation and hot metal quality. During production of coke, coke fines are generated, which is used in sinter plant. In steel industry wherever excess of coke fines are generated, it becomes problematic to dispose these coke fines. Coke making process has passed through various stages of development over a period of time. Various types of catalyst, non-coking coals and chemical addition have been attempted in coal blend to improve the coke quality and to reduce the cost of coke. A study has been conducted where coke fines has been used in coal blend. This paper presents the salient points of the investigation on the effect of coke fines addition on M10 and M25 value of coke. [ABSTRACT FROM AUTHOR]

The concentration of radon in groundwater is mainly governed by the radium content in the rocks of the aquifer. The internal exposure to high levels of radon in water is directly associated with the radiological risk to members of public. In this work, radon concentrations were measured in groundwater of Garhwal Himalaya, India, using scintillation detector-based RnDuo and silicon detector-based RAD7 monitors. An inter-comparison exercise was carried out between RnDuo and RAD7 techniques for a few samples to validate the results. The radiation doses associated with the exposure to radon in water were estimated from measured values of activity concentrations. An attempt has been made to see the effect of geology, geohydrology and different types of sources on radon levels in Himalayan groundwater. The experimental techniques and results obtained are discussed in detail. [ABSTRACT FROM AUTHOR]

In order to map the thoron prone areas of the coastal region of Kollam district, a well known HBRA of south India, comparative study of radon and thoron exhalation rate was conducted. The in situ measurement of radon and thoron exhalation has been taken. These studies were correlated with the gamma radiation level. The average value of thoron exhalation is found to 5.55 ± 1.35 Bq m s along the coastal areas and the radon exhalation rate is found to 107.6 ± 32 Bq m h. The value of thoron exhalation was found 12 times greater than the global values in Neendakara and Chavara region and about 6 times greater in the Alappad region. [ABSTRACT FROM AUTHOR]

The present study utilizes the latest solid state nuclear track detectors based single entrance radon-thoron twin chambers, direct radon/thoron progeny sensors to measure indoor radon, thoron, and their progenies. From the measured values of radon, thoron and their progenies concentrations, radon and thoron equilibrium factors and annual effective inhalation dose have been estimated. The mean values of equilibrium factor for radon and thoron in studied dwellings have been found to be 0.52 ± 0.19 and 0.013 ± 0.006 respectively. The mean value of annual effective dose is estimated as 1.02 ± 0.41 mSv. Seasonal and different types of house wise variations of radon, thoron and their progenies are discussed in detail. [ABSTRACT FROM AUTHOR]

The change in morphology, structure, catalytic activity and ac electrical conductivity of the Sr-doped ZnO (ZnSrO, x = 0, 0.01, 0.02 and 0.03) ceramic powders was investigated after sintering. The sintering of the Sr-doped samples results in faster growth in particle-size and the shape becomes spherical by dissolution of the sharp edges in order to reduce the strain produced by Sr-doping and to reduce the surface energy. The growth in particle-size reduces the photocatalytic activity. Sr-doping reduces the band gap of ZnO by a small value (~0.1 eV). The ac conductivity values decrease with increase in Sr-concentration, but increase with temperature and frequency. This behavior is due to the conduction by small polarons created by Sr-doping. Our results may facilitate a way for the easy fabrication of monolithic ZnO based devices with improved dielectric and semiconducting properties of ZnO ceramics by doping a small amount of Sr. [ABSTRACT FROM AUTHOR]

Using an evolutionary structure search algorithm lanthanum trifluoride (LaF) has been examined under hydrostatic compression. The comparison of enthalpies of various candidate structures suggests that at ambient condition the tysonite structure (space group P-3 c1) is the lowest enthalpy phase. Further it has been found that this structure transforms to a primitive orthorhombic structure (space group Pmmn) around ~19.5 GPa, which is in reasonable agreement with the experimental value of 16 GPa. Upon further compression the orthorhombic structure has been predicted to transform to another orthorhombic phase with space group symmetry Cmcm at ~150 GPa. The results of the static lattice calculations have been substantiated by testing the lattice dynamic stability of these phases in the regime of their structural stability. Additionally, various Raman active modes for both the P-3 c1 and Pmmn structures have been calculated as a function of pressure. The theoretically derived Raman active modes calculated for both the phases at various pressures display a good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

We present an experimental technique to measure light shifts due to the nuclear spin independent (NSI) parity-nonconserving (PNC) interaction in the $$7S_{1/2}$$ - $$6D_{3/2}$$ transition in ultracold $${^{210}\mathrm{Fr}}$$ atoms. The approach we propose is similar to the one by Fortson (Phys Rev Lett 70:2383, 10) to measure the PNC-induced light shift which arises from the interference of parity nonconserving electric dipole transition and electric quadrupole transition amplitudes. Its major advantage is that it can treat more than $$10^4$$ ultracold $${^{210}\mathrm{Fr}}$$ atoms to enhance the shot noise limit. A relativistic coupled-cluster method has been employed to calculate the electric dipole transition amplitudes arising from the PNC interaction. Based on these calculations, we have evaluated the PNC-induced light shifts for transitions between the hyperfine levels of the $$7S_{1/2}$$ and $$6D_{3/2}$$ states and suitable transitions are identified for carrying out PNC measurements. It is possible in principle to probe new physics beyond the standard model with our proposed experimental scheme. [ABSTRACT FROM AUTHOR]

We measured the isotope shift in the $$^2{\mathrm {S}}_{{1}/{2}}$$ $$\rightarrow $$ $$^2{\mathrm {P}}_{{3}/{2}}$$ (D2) transition in singly ionized calcium ions using photon recoil spectroscopy. The high accuracy of the technique enables us to compare the difference between the isotope shifts of this transition to the previously measured isotopic shifts of the $$^2{\mathrm {S}}_{{1}/{2}}$$ $$\rightarrow $$ $$^2{\mathrm {P}}_{{1}/{2}}$$ (D1) line. This so-called splitting isotope shift is extracted and exhibits a clear signature of field shift contributions. From the data, we were able to extract the small difference of the field shift coefficient and mass shifts between the two transitions with high accuracy. This J-dependence is of relativistic origin and can be used to benchmark atomic structure calculations. As a first step, we use several ab initio atomic structure calculation methods to provide more accurate values for the field shift constants and their ratio. Remarkably, the high-accuracy value for the ratio of the field shift constants extracted from the experimental data is larger than all available theoretical predictions. [ABSTRACT FROM AUTHOR]

In this article we have investigated theoretically the effect of built-in-polarization field on various phonon scattering mechanisms in AlGaN alloy. The built-in-polarization field of AlGaN modifies the elastic constant, group velocity of phonons and Debye temperature. As a result, various phonon scattering mechanisms are changed. Important phonon scattering mechanisms such as normal scattering, Umklapp scattering, point defect scattering, dislocation scattering and phonon-electron scattering processes have been considered in the computation. The combined relaxation time due to above-mentioned scattering mechanisms has also been computed as a function of phonon frequency for various Al compositions at room temperature. It is found that combined relaxation time is enhanced due to built-in-polarization effect and makes phonon mean free path longer, which is required for higher optical, electrical and thermal transport processes. The result can be used to determine the effect of built-in-polarization field on optical and thermal properties of AlGaN and will be useful, particularly, for improvement of thermoelectric performance of AlGaN alloy through polarization engineering. [ABSTRACT FROM AUTHOR]

Thoron exhalation from earth's surface is the most important source of environmental thoron. The High Background Radiation Areas (HBRAs) of Kerala and Odisha in India have beaches with sands enriched with monazite, an ore of thorium, making it unique for study of thoron exhalation. In the present study, in situ measurement of thoron exhalation was carried out to map the thoron exhalation rate over complete coastline of the known HBRAs. New experimental setups for measurement of thoron surface exhalation and thoron mass emanation were developed and validated. The exhalation measurements were carried out on beaches of Chavara-Neendakara (CN) area of Kerala and Chatrapur (CH) region of Odisha. The beaches of the Kerala region showed an average thoron exhalation rate of 5.95 ± 2.98 Bq ms, which for the beaches of Chatrapur area of Odisha was 2.77 ± 0.96 Bq ms. The external gamma exposure rate was also measured at these locations, and it was observed to be well correlated with in situ thoron exhalation rate. Sand samples were collected from ten of the measurement locations and analyzed in the laboratory for a further understanding of thoron exhalation process in the beach sand. Measurement of specific thoron mass emanation rate, specific 224Ra content and thoron emanation coefficient was taken for the samples. A good correlation was found between in situ thoron exhalation rate and specific thoron mass emanation rate. The effective thoron diffusion length was determined by using the measured parameters in the UNSCEAR radon exhalation model and was found to be nearly constant with a value of 2.2 ± 0.36 cm. This study shows that in spite of very high thorium content (500-1000 times) as compared to normal fine soils, the thoron exhalation from the HBRA beach sands was only 4-12 times higher due to very low emanation coefficient, about 1000 times smaller than that for normal soils. [ABSTRACT FROM AUTHOR]