A facile microwave-assisted combustion method was adopted to synthesize pure ZnO and Mg-doped ZnO nanoparticles (NPs), and characterization of the NPs and the sorption behavior with Congo Red (CR) ...Azo dye was extensively investigated. The structure, morphology and chemical assay of the synthesized NPs were studied with respect to the pure and 2% Mg-doped ZnO samples. The X-ray diffraction pattern confirmed the presence of crystalline, cubic phase with fluorite structure of both the NPs. The morphological differences between the pure and Mg-doped ZnO NPs were evaluated by FE-SEM, which revealed that the NPs were in the nanoscale regime with irregular crystalline morphology having a grain size of ~18–45 nm. N2 adsorption/desorption isotherms measured at −196 °C suggested a Type II structure with limited hysteresis loops, likely due to some interparticle porosity. The BET SSA ZnO NPs obtained was found to be 32 m2 g−1, indicating about its potential in sorption processes. Batch adsorption study for the removal of CR carried out showed that, the Mg-doped NPs showed higher loading efficiency (125 mg·g−1) than the ZnO NPs (25 mg·g−1) counterpart. This was corroborated by the isotherm results in which the CR dye sorption followed a Freundlich Isotherm model for both undoped ZnO and Mg-doped ZnO NPs. The sorption of CR dye followed a pseudo-second order kinetics. The negative ΔG° (−31.91 and −109.41 kJ mol−1) showed the feasibility of the adsorption process. The ΔH° was determined as +13.74 kJ mol−1 and 50.7 kJ mol−1 for ZnO NPs and Mg doped-ZnO NPs respectively, confirming the endothermic nature of the adsorption for removing CR dye from the solution.
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•Synthesis of ZnO and Mg-doped ZnO nano particles by microwave-assisted combustion method.•2%Mg-doped ZnO nano particles showed better sorption of CR dye than ZnO NPs as it is.•Sorption of CR dye with both the nano particles follows pseudo-second order kinetics.•Thermodynamic study reveals endothermic in nature of CR dye sorption with ZnO/Mg doped-ZnO NPs.•Quantitative removal of CR dyes by Mg-doped ZnO NPs was achieved with loading capacity of 125 mg/g.
Mycoplasma bovis
is one of the important bovine mycoplasma involved in economically important clinical conditions like respiratory diseases, otitis media, and mastitis. The present study was ...undertaken with the objective of developing a SYBR Green dye-based real-time PCR assay targeting
uvr
C gene for the diagnosis of
M. bovis
. The analytical sensitivity and specificity of the assay were evaluated. The test showed 10
3
-fold more sensitivity than conventional PCR and detected down to 100 fg level of DNA. It was found to be specific, as no cross reactivity was shown with other related bacteria and
Mycoplasma
species. The developed assay was able to detect down to 40 copies of
uvrC
gene from spiked bovine milk samples. At present, this developed assay may be used as a valuable diagnostic tool for the detection of
Mycoplasma bovis
.
The safe disposal and utilisation of coal fly ash (CFA) for value addition are still major problems worldwide. Al2O3 is a major valued material associated with it. Till date no methods are available ...to treat CFA for recovering its valued materials. Leaching of alumina from CFA in an economical way is very difficult, which either requires higher chemical consumption or application of stringent reaction conditions such as high temperature and pressure. In this paper a simple alternative method has been attempted to dissolve alumina from CFA. Addition of fluoride ion as HF improved the acid leaching performance of fly ash to a large extent. XRD data showed mullite, the alumina bearing phase, as the major phase which gets dissolved during leaching operation. A standard procedure for the precipitation of alumina can be employed after the leached solution is obtained.
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•NALCO fly ash contains mullite the main phase bearing alumina.•A simple alternative method has been attempted to dissolve alumina from fly ash.•H2SO4 leaching in the presence of HF showed alumina leaching efficiency of ~92%.•The XRD data showed the dissolution of mullite grains during leaching.•The leaching condition is suitable for downstream operations to obtain alumina.
This paper proposed a novel approach to determine the optimal trajectory of the path for multi-robots in a clutter environment using hybridization of improved particle swarm optimization (IPSO) with ...differentially perturbed velocity (DV) algorithm. The objective of the algorithm is to minimize the maximum path length that corresponds to minimize the arrival time of all the robots to their respective destination in the environment. The robots on the team make independent decisions, coordinate, and cooperate with each other to determine the next positions from their current position in the world map using proposed hybrid IPSO-DV. The proposed scheme adjusts the velocity of the robots by incorporating a vector differential operator inherited from Differential Evolution (DE) in IPSO. Finally the analytical and experimental results of the multi-robot path planning have been compared to those obtained by IPSO-DV, IPSO, DE in a similar environment. Simulation and khepera environment results are compared with those obtained by IPSO-DV to ensure the integrity of the algorithm. The results obtained from Simulation as well as Khepera environment reveal that, the proposed IPSO-DV performs better than IPSO and DE with respect to optimal trajectory path length and arrival time.
Abstract The silicon vertex detector (SVD) is installed at the heart of the Belle II experiment, taking data at the high-luminosity B-Factory SuperKEKB since 2019. The SVD is a four-layer ...double-sided strip detector with tracking and particle-identification capabilities. In this paper, we report on the performance of the reconstruction of SVD hits. The detector has shown a stable and above-99% hit efficiency, with a large signal-to-noise in all sensors since the beginning of data taking. Cluster position and time resolution have been measured with 2020 and 2022 data and show excellent performance and stability. In particular, the cluster-position resolution is between 7 and 12 μm for the small-pitch sensors, in reasonable agreement with the expectations, while the cluster time resolution is measured to be below 3 ns. The effect of radiation damage is visible, but not affecting the performance. As the luminosity increases, higher machine backgrounds are expected and the excellent hit-time information in SVD can be exploited for background rejection. In particular, we have recently developed a novel procedure to select hits by grouping them event-by-event based on their time. This new procedure allows a significant reduction of the fake rate, while preserving the tracking efficiency, and it has therefore replaced the previous cut-based procedure. We have developed a method that uses the SVD hits to estimate the track time (previously unavailable) and the collision time. It has a similar precision to the estimate based on the drift chamber readout but its execution time is three orders of magnitude smaller, allowing a faster online reconstruction that is crucial in a high luminosity regime. The track time is a powerful information that allows, together with the aforementioned grouping selection, to raise the occupancy limit above that expected at nominal luminosity, leaving room for a safety factor. Finally, in June 2022 the data taking of the Belle II experiment was stopped to install a new two-layer DEPFET detector (PXD) and upgrade components of the accelerator. The whole silicon tracker (PXD+SVD) has been extracted from Belle II, the new PXD installed, the detector closed and commissioned. We briefly describe the SVD results of this upgrade.
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•Extraction of V by organic acid follows order; Citric > Tartaric > Acetic > Formic > Oxalic.•Leaching Kinetics investigation of vanadium (V) from spent catalyst by citric ...acid.•Apparent Ea of 11.21 KJ.mole-1 resulted for V ascertained diffusion control leaching.•Leaching of V, Mg &Fe follows Shrinking-core model (1-23X-(1-X)2/3=8bDc1-eρd02t=kapt).•EDAX and XRD of leach residue confirms on complete dissolution of V by citric acid.
The extraction and leaching kinetics of V from the spent catalyst (3.06 %V, 10.01% Fe and 0.52 % Mg) was investigated using organic citric acid. The characterization of the spent catalyst sample by XRD, EDAX and SEM was examined to ascertain the existence of V, Mg and Fe in the form of respective oxides. Different organic acids were tested to ensure the leaching performance towards extraction of V, Fe and Mg and based upon the efficacy, the metal extrication trend followed the order as; Citric acid > Tartaric acid > Acetic acid > Formic acid > Oxalic acid. The critical parameters such as citric acid concentration, agitation speed, temperature, S/L and particle size, affecting on either of the metal leaching was systematically examined at varying time extent to establish the leaching mechanism as well as for attaining suitable optimum condition for effective dissolution of vanadium. The leaching kinetics of V, Mg and Fe was governed by diffusion controlled mode while following to shrinking core model mechanism as evident from the correlation coefficient (R2 = 0.99) and the resultant activation energy (11.21 kJ/mole for V, 10.86 kJ/mole for Mg and 11.84 kJ/mole, for Fe). The dissolution behaviour of either of metals examined at various particle size ranges as well as citric acid concentrations follows the linearity trend with above proposed leaching kinetics model. More than 99% of Vanadium, 80% Fe and 75 % Mg leaching was resulted at the optimum condition: S/l: 4%, Citric acid: 1.0 M, temp: 373 K, Particle size: 46-75micron. The residue obtained after leaching at the above optimum condition was further analyzed by XRD and EDAX, indicating no peak due to Vanadium and confirms on almost all extraction of V from the spent catalyst phase.
Abstract Aeromonas hydrophila is a Gram-negative bacteria associated with many disease conditions of aquatic animals. Two rough attenuated variants were derived from two smooth virulent types of this ...bacterium by continuous passage separately in laboratory over a period of 8 years in brain–heart infusion agar. These variants were checked to be rough lipopolysaccharides (LPS) types and attenuated since they neither produced any disease nor mortality in the injected fishes. The immunogenic potential of these variants remained unaltered as compared to parent smooth types and fish immunized with these variants resisted the infection and mortality upon cross challenge. Because of their intact immunogenic potential and loss of virulence, they may be used as candidates for fish immunization.
In search of a suitable resource conservation technology under pigeonpea (Cajanus cajan L.)–wheat (Triticum aestivum L.) system in the Indo-Gangetic Plains, the effects of conservation agriculture ...(CA) on crop productivity and water-use efficiency (WUE) were evaluated during a 3-year study. The treatments were: conventional tillage (CT), zero tillage (ZT) with planting on permanent narrow beds (PNB), PNB with residue (PNB + R), ZT with planting on permanent broad beds (PBB) and PBB + R. The PBB + R plots had higher pigeonpea grain yield than the CT plots in all 3 years. However, wheat grain yields under all plots were similar in all years except for PBB + R plots in the second year, which had higher wheat yield than CT plots. The contrast analysis showed that pigeonpea grain yield of CA plots was significantly higher than CT plots in the first year. However, both pigeonpea and wheat grain yields during the last 2 years under CA and CT plots were similar. The PBB + R plots had higher system WUE than the CT plots in the second and third years. Plots under CA had significantly higher WUE and significantly lower water use than CT plots in these years. The PBB + R plots had higher WUE than PNB + R and PNB plots. Also, the PBB plots had higher WUE than PNB in the second and third years, despite similar water use. The interactions of bed width and residue management for all parameters in the second and third years were not significant. Those positive impacts under PBB + R plots over CT plots were perceived to be due to no tillage and significantly higher amount of estimated residue retention. Thus, both PBB and PBB + R technologies would be very useful under a pigeonpea–wheat cropping system in this region.
Operation and performance of the Resistive Plate Chambers (RPCs) mostly depend on the quality and characteristics of the electrode materials. The India-based Neutrino Observatory collaboration has ...chosen glass RPCs as the active detector elements for its Iron Calorimeter detector and is going to deploy RPCs in an unprecedented scale. Therefore, it is imperative that we study the electrode material aspects in detail. We report here, systematic characterization studies on the glasses from two manufacturers. RPC detectors were built using these glasses and performances of the same were compared with their material properties.
The Belle II silicon vertex detector is one of the vertex detectors in the Belle II experiment. The detector reads out the signals from the double-sided silicon strip sensors with the APV25 front-end ...readout ASIC, adopting the chip-on-sensor concept to minimize the strip noise. The detector has been operated in the experiment since the spring of 2019. Analyzing the acquired data during the beam collisions, the excellent performance of the detector is confirmed. Also, the radiation dose and 1-MeV equivalent neutron fluence of the detector are estimated using the measured dose rates of the diamond sensors installed on the beam pipe and are compared with the measured radiation effects in the strip noise, leakage current, and depletion voltage. This paper briefly introduces the main features of the silicon vertex detector, and then reports on the measured performance and radiation effects of the first two years of running experience of the detector.
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