2,588 research outputs found
Liquid-liquid mixing in stirred tanks with varying liquid depths
Considerable attention has been devoted in the past to the determination of the minimum agitation speed, Ncd, required for the complete dispersion of two immiscible liquids in mechanically stirred tanks. When this situation is achieved the dispersed phase is no longer present as a distinct layer, such as a light oil phase above an aqueous solution, but becomes completely dispersed, in the form of droplets, throughout the continuous phase. The achievement of the dispersed state is of significant importance in many industrial operations. Nevertheless, the effect on Ncd of a number of operating variables remains poorly understood. In particular, the effect on Ncd of the liquid depth, H, has not been established, especially at different values of the impeller off-bottom clearances, C. This situation is especially common, and potentially critical, in a number of processes in the pharmaceutical and food industries, when the completely dispersed state must be maintained at all times as the vessel is either charged with a liquid or emptied.
This investigation is focused on the experimental determination of the minimum agitation speed and power dissipation required to completely disperse two immiscible liquids at different liquid heights and impeller off-bottom clearances. Two types of impellers were used here: a six-blade disc turbine and a six-blade (45Âş) pitched-blade turbine. The minimum agitation speed was first experimentally determined using a visual approach. In order to validate visual observation method, a previously developed sampling method was also used (Armenante, P.M. and Huang, Y.T., Ind. Eng. Chem. Res., 31: 1395-1406, 1992). This method is based on sampling the liquid-liquid mixture at different agitation speeds, determining the content of the dispersed phase in each sample, and analyzing the data so obtained using a mathematical model.
Ncd and the corresponding power, P, drawn by the impeller at Ncd were found to be strongly affected by the impeller type, as expected. However, they were also significantly affected by both the liquid height and the impeller off-bottom clearance. Typically, both Ncd and P decreased with decreasing H. The effect of C was more complex. Of even greater significance, it was observed that, for specific combinations of H and C, and especially when the liquid head above the impeller was below a critical value, the state of complete liquid-liquid dispersion was not achievable, irrespective of the agitation speed. This implies that operating in regions where Ncd cannot be achieved should be avoided if complete liquid-liquid dispersion is to be maintained. The results of this investigation are expected to be of significant importance in the industrial practice
Elemental Analysis of Soil Samples Using Thick Target-Particle Induced X-Ray Emission (TT-PIXE) Technique
In this work thick target-proton induced x-ray emission (TT-PIXE) technique has been employed for the elemental analysis of soil samples collected from Budha nullah region of Ludhiana city, Punjab. TT-PIXE analysis of samples has been carried out using 3 MeV proton beam from 3 UD pelletron (9SDH2 from NEC, USA) facility at the Institute of Physics (IOP), Bhubaneswar, Orissa. The emitted x-rays were detected using Si(Li) detector (CANBERRA US, FWHM = 180 eV at 5.9 keV) positioned at 90° to the beam line and using suitable electronics. The trace elements 15P, 16S, 19K, 20Ca, 22Ti, 24Cr, 25Mn, 26Fe, 29Cu, 30Zn, 33As, 37Rb, 38Sr, and 82Pb were quantified in the soil samples. The quantitative estimation of PIXE spectrum of the soil samples was performed using GUPIX computer code. The presence of 24Cr, 33As, and 82Pb toxic elements in soils is likely to be due to the pollution caused by seepage of the water at the breached locations of nullah. The present study brings to focus the need to improve the effluent treatment of the industrial wastes and repair of the breached Budha nullah. In comparison to other analytical techniques for elemental analysis, PIXE is sensitive and its multi-elemental character brings advantage to investigators for the determination of minor and trace elements in a variety of soil samples
Scene Based Text Recognition From Natural Images and Classification Based on Hybrid CNN Models with Performance Evaluation
Similar to the recognition of captions, pictures, or overlapped text that typically appears horizontally, multi-oriented text recognition in video frames is challenging since it has high contrast related to its background. Multi-oriented form of text normally denotes scene text which makes text recognition further stimulating and remarkable owing to the disparaging features of scene text. Hence, predictable text detection approaches might not give virtuous outcomes for multi-oriented scene text detection. Text detection from any such natural image has been challenging since earlier times, and significant enhancement has been made recently to execute this task. While coming to blurred, low-resolution, and small-sized images, most of the previous research conducted doesn’t work well; hence, there is a research gap in that area. Scene-based text detection is a key area due to its adverse applications. One such primary reason for the failure of earlier methods is that the existing methods could not generate precise alignments across feature areas and targets for those images. This research focuses on scene-based text detection with the aid of YOLO based object detector and a CNN-based classification approach. The experiments were conducted in MATLAB 2019A, and the packages used were RESNET50, INCEPTIONRESNETV2, and DENSENET201. The efficiency of the proposed methodology - Hybrid resnet -YOLO procured maximum accuracy of 91%, Hybrid inceptionresnetv2 -YOLO of 81.2%, and Hybrid densenet201 -YOLO of 83.1% and was verified by comparing it with the existing research works Resnet50 of 76.9%, ResNet-101 of 79.5%, and ResNet-152 of 82%
EDXRF Analysis of Some Fungal Species for the Uptake Capacity of 28Ni, 48Cd, and 82Pb Metal Ions From Aqueous Solution
In this paper, Energy Dispersive X-ray Fluorescence (EDXRF) analysis of eight fungi species, namely, Aspergillus niger, Aspergillus terreus, Trichoderma longibrachiatum, Trichoderma fasciculatum, Penicillin Janthinellum, Aspergillus awamori, Phanerochaete chrysosporium, and Rhizopus arrhizus for the uptake capacity of 28Ni, 48Cd, and 82Pb metals ions from aqueous solution have been reported. Fungal samples having superior ion removal capacity through bioaccumulation and biosorption were obtained from sites contaminated with heavy metals. The detection limit in EDXRF set up was improved considerably using selective absorbers in the path of incident photons from the X-ray tube to reduce the background in the desired energy region. It has been observed that all fungi species under present study have greater affinity for 82Pb ions as compared to 28Ni and 48Cd metal ions. The Trichoderma longibrachiatum and Trichoderma fasciculatum fungi species were identified to be more efficient for removal of heavy metal ions from waste water. The measured uptake capacity of Trichoderma longibrachiatumfor 28Ni, 48Cd, and 82Pb ions from aqueous solution is 0.52 mg/g, 0.97 mg/g, and 6.4 mg/g, respectively, and for Trichoderma fasciculatum it is 0.43 mg/g, 0.79 mg/g, and 3.5 mg/g, respectively. This indicated the potential of these identified fungi species as biosorbent for removal of high metal ions from waste water and industrial effluents
Extremum uncertainty product and sum states
We consider the states with extremum products and sums of the uncertainties in non-commuting observables. These are illustrated by two specific examples of harmonic oscillator and the angular momentum states. It shows that the coherent states of the harmonic oscillator are characterized by the minimum uncertainty sum <(Δq)2> + <(Δp)2>. The extremum values of the sums and products of the uncertainties of the components of the angular momentum are also obtained
Therapy Related Chronic Myeloid Leukemia (trCML) or non-Therapy Related Second Malignancy Chronic Myeloid Leukemia (smCML) following Diffuse Large B-Cell Lymphoma(DLBCL): A Case Report and Review of Literature
  Introduction: Second malignancy could be either previous therapy related or non-therapy related like syndromic or shared etiologic exposure. It could be either a hematological/solid malignancy following tretment for previous solid tumour or prior hematological malignanacy.Review of literature regarding secondary Chronic Myeloid Leukemia (CML) following previous active treatment for primary cancer is listed out for further understanding.Presentation of Case: We describe a 71 year old elderly male who developed Chronic Myeloid Leukemia(CML) after a period of 6 years during follow up of Stage IV Diffuse Large B-Cell Lymphoma(DLBCL) for which he received 8 cycles of R-CHOP based Chemo-immunotherapy in 2008 .Whether it is therapy related Chronic Myeloid Leukemia (trCML) following prior cytotoxic treatment or simply a non-therapy related second malignancy hronic Myeloid Leukemia(smCML) is a matter of debate.However our patient responded dramatically like denova CML to imatinib therapy.Conclusion: Therapy related CML or non therapy related second malignancy CML following DLBCL treatment is rare but responds dramatically like denova CML to imatinib therapy.    Â
Association of volume of first trimester subchorionic hemorrhage with pregnancy outcome
Background: Vaginal bleeding during the first trimester of pregnancy may or may not be associated with subchorionic hemorrhage (SCH). The volume of SCH may affect foetal growth or development. The aim of the study was to determine the impact of first trimester pregnancy SCH on pregnancy outcome.
Methods: 151 women each in two groups (with and without SCH), all with first trimester bleeding were enrolled, monitored throughout pregnancy and outcome noted.
Results: 72.8% women with SCH and 78.1% women without SCH gave birth to a live neonate. The relative risk of pregnancy wastage (spontaneous abortion, antepartum or intrapartum stillbirth) for the women with SCH was 1.22 (95% CI 0.81-1.82; p value =0.33) as compared to those with no SCH. 97% of women with SCH>10 ml had pregnancy wastage (mostly aborted before 20 weeks), 40% of women with SCH>5-10 ml had pregnancy wastage (p<0.001).
Conclusions: The mere presence of SCH did not increase the risk of adverse pregnancy outcomes. However, a large volume of SCH significantly increased the risk of pregnancy wastage in comparison to a smaller SCH.
Bacteriological profile and antibiogram of blood culture isolates from patients of rural tertiary care hospital
Microbial invasion of blood stream is associated with significant mortality and morbidity. Identification of bacterial isolates and antibiotic susceptibility of bacteria isolated from blood culture would guide the antibiotics treatment for patients with bacteremia. 1) To determine age – wise blood culture positivity rate in bacteremia 2) To identify age – wise common bacterial species isolates in bacteremia 3) To determine Antibiotic sensitivity pattern of the bacterial isolates. Atotal of 247 blood culture samples received from various clinical departments of rural teaching hospital from August 2013 to September 2015 were included in the study. Samples were collected in brain heart infusion broth. Identification of isolates and antimicrobial susceptibility was done as per standard microbiological methods. Out of 247 specimens bacteria sp. was isolated from 46 (18.62%) samples. Blood culture positivity was noted highest among neonates age group (38.71%). Lowest rate was observed among elders (4.55%). Klebsiella pneumoniae, Coagulase negative staphylococcus (CONs), and S. aureus were common blood culture isolates. In neonates Klebsiella pneumoniae was the most common isolate. Out of 27 gram negative bacilli, 14 (51.85%) were extended spectrum betalactamases (ESBL) positive. High resistance was noted against amoxycillin and amoxicillin/clavulanic acid and third generation cephalosporins in all gram negative organisms except, S. typhi. Out of 12 Staphylococcus sp., none of these were methicillin resistant. Routine antibiotic susceptibility surveillance helps in choice of antibiotics for treatment, identification of resistance and control of its spread. Published by the International journal of Microbiology and Mycology (IJMM
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