scholarly journals Indirect Manganese Removal byStenotrophomonassp. andLysinibacillussp. Isolated from Brazilian Mine Water

2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
Natália Rocha Barboza ◽  
Soraya Sander Amorim ◽  
Pricila Almeida Santos ◽  
Flávia Donária Reis ◽  
Mônica Mendes Cordeiro ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Mine Water ◽  
High Stability ◽  
Culture Medium ◽  
Bacterial Consortium ◽  
Bacterial Isolates ◽  
Electronic Microscopy ◽  
Mining Operations ◽  
X Ray ◽  
Manganese Removal

Manganese is a contaminant in the wastewaters produced by Brazilian mining operations, and the removal of the metal is notoriously difficult because of the high stability of the Mn(II) ion in aqueous solutions. To explore a biological approach for removing excessive amounts of aqueous Mn(II), we investigated the potential of Mn(II) oxidation by both consortium and bacterial isolates from a Brazilian manganese mine. A bacterial consortium was able to remove 99.7% of the Mn(II). A phylogenetic analysis of isolates demonstrated that the predominant microorganisms were members ofStenotrophomonas,Bacillus, andLysinibacillusgenera. Mn(II) removal rates between 58.5% and 70.9% were observed forBacillussp. andStenotrophomonassp. while theLysinibacillusisolate 13P removes 82.7%. The catalytic oxidation of Mn(II) mediated by multicopper oxidase was not properly detected; however, in all of the experiments, a significant increase in the pH of the culture medium was detected. No aggregates inside the cells grown for a week were found by electronic microscopy. Nevertheless, an energy-dispersive X-ray spectroscopy of the isolates revealed the presence of manganese inStenotrophomonassp. andLysinibacillussp. grown in K medium. These results suggest that members ofStenotrophomonasandLysinibacillusgenera were able to remove Mn(II) by a nonenzymatic pathway.

New Structure of CTAB Templated Silica Films as revealed by GISAXS coupled to HRTEM

2000 ◽  
Vol 628 ◽  
Author(s):  
Sophie Besson ◽  
Catherine Jacquiod ◽  
Thierry Gacoin ◽  
André Naudon ◽  
Christian Ricolleau ◽  
...  
Keyword(s):  
Cetyltrimethylammonium Bromide ◽  
Grazing Incidence ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
Electronic Microscopy ◽  
Silica Films ◽  
X Ray ◽  
X Ray Scattering ◽  
Hexagonal Arrangement ◽  
Spherical Micelles

ABSTRACTA microstructural study on surfactant templated silica films is performed by coupling traditional X-Ray Diffraction (XRD) and Transmission Electronic Microscopy (TEM) to Grazing Incidence Small Angle X-Ray Scattering (GISAXS). By this method it is shown that spin-coating of silicate solutions with cationic surfactant cetyltrimethylammonium bromide (CTAB) as a templating agent provides 3D hexagonal structure (space group P63/mmc) that is no longer compatible with the often described hexagonal arrangement of tubular micelles but rather with an hexagonal arrangement of spherical micelles. The extent of the hexagonal ordering and the texture can be optimized in films by varying the composition of the solution.

High-Stability Flexible X-ray Detectors Based on Lead-Free Halide Perovskite Cs2TeI6 Films

2021 ◽  
Author(s):  
Jun Guo ◽  
Yadong Xu ◽  
Wenhui Yang ◽  
Bao Xiao ◽  
Qihao Sun ◽  
...  
Keyword(s):  
High Stability ◽  
Lead Free ◽  
X Ray ◽  
Halide Perovskite

Hydrothermal Treatment of Coprecipitated YSZ Powders

2010 ◽  
Vol 660-661 ◽  
pp. 983-988 ◽  
Author(s):  
Alexander Rodrigo Arakaki ◽  
Walter Kenji Yoshito ◽  
Valter Ussui ◽  
Dolores Ribeiro Ricci Lazar
Keyword(s):  
Surface Area ◽  
Hydrothermal Treatment ◽  
Gas Adsorption ◽  
X Ray Diffraction ◽  
Electronic Microscopy ◽  
Immersion Method ◽  
Cubic Symmetry ◽  
X Ray ◽  
Granulometric Analysis ◽  
Symmetry Surface

Zirconia stabilized with 8.5 mol% yttria (YSZ) were synthesized by coprecipitation and resulting gels were hydrothermallly treated at 200°C and 220 PSI for 4, 8 and 16 hours. Products were oven dried at 70°C for 24 hours, isostatically pressed as pellets and sintered at 1500 °C for 1 hour. Powders were characterized for surface area with N2 gas adsorption, X-ray diffraction, laser diffraction granulometric analysis and scanning and transmission electronic microscopy. Density of ceramics was measured by an immersion method based on the Archimedes principle. Results showed that powders dried at 70°C are amorphous and after treatment has tetragonal/cubic symmetry. Surface area of powders presented a significant reduction after hydrothermal treatment. Ceramics prepared from hydrothermally treated powders have higher green density but sintered pellets are less dense when compared to that made with powders calcined at 800°C for 1 hour due to the agglomerate state of powders. Solvothermal treatment is a promising procedure to enhance density.

Isolation and Characterization of Cellulose Degrading Bacteria of Termite Gut from North Eastern Region of India

2016 ◽  
Vol 5 (6) ◽  
pp. 283-290
Author(s):  
Sonika Sharma ◽  
Soumya Chatterjee ◽  
Sibnarayan Datta ◽  
Rajesh Kumar Prasad ◽  
Angkita Sharma ◽  
...  
Keyword(s):  
Agar Plate ◽  
Bacterial Consortium ◽  
Cellulase Production ◽  
Eastern Region ◽  
Bacterial Isolates ◽  
Carbohydrate Utilization ◽  
North East ◽  
Isolation And Characterization ◽  
Degrading Bacteria ◽  
Termite Gut

A study was conducted to screen and isolate cellulase producing bacteria of termite gut from North east region of India. A total of 27 culturable bacterial isolates were screened for cellulase production. Out of the 27 bacterial isolates 11 showed zone of clearance on CMC agar media on staining with 1% Congo red, suggesting potential cellulose degrading activity. The maximum hydrolysis capacities (HC value) on CMC agar plate was found within the range of 3.6 to 40mm. The morphological characterization and gram staining of the positive isolates indicated that 3 isolates were positively stained rods and others were negative cocci. All the cellulase positive isolates were also tested for carbohydrate utilization with maltose, dextrose and fructose, to which all the 11 isolates responded positively. Further, based on the amplification and sequencing of the 16S rRNA genetic region, isolates were identified as member of the genus Bacillus, Paenibacillus and Staphylococcus. The degrading potential of these bacteria were assessed by developing bacterial consortium and efficient degradation was reported after seven days of incubation with different cellulose source like rice, cotton and rice husk.

scholarly journals In Vivo X-ray Computed Tomography Investigations of Crack Damage Evolution of Cemented Waste Rock Backfills (CWRB) under Uniaxial Deformation

Minerals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 539 ◽  
Author(s):  
Yu Wang ◽  
Changhong Li ◽  
Zhiqiang Hou ◽  
Xuefeng Yi ◽  
Xiaoming Wei
Keyword(s):  
Computed Tomography ◽  
Damage Evolution ◽  
Waste Rock ◽  
Crack Identification ◽  
Mining Operations ◽  
Cracking Behavior ◽  
Value Analysis ◽  
X Ray ◽  
Waste Rocks ◽  
X Ray Computed

Cemented waste rock backfill (CWRB), which is a mixture of tailings, waste rock, cement, and water, is subjected to combination actions in underground mining operations and has been widely used in deep resource mining. While the strength requirement and macroscopic deformation behaviors of CWRB have been well studied, the mesoscopic damage evolution mechanisms are still not well understood. In this work, a CWRB sample with a waste rock proportion of 30% was studied with a uniaxial compression test under tomographic monitoring, using a 450 kV industrial X-ray computed tomography (CT). Clear CT images, CT value analysis, crack identification, and extraction reveal that CWRB damage evolution is extremely inhomogeneous and affected by the waste rock size, shape, and distribution. Furthermore, the crack initiation, propagation, and coalescence behaviors are limited to the existing waste rocks. When deformation grows to a certain extent, the cracks demonstrate an interlocking phenomenon and their propagation paths are affected by the waste rocks, which may improve the ability to resist compressive deformation. Volumetric dilatancy caused by the damage and cracking behavior has closed a link with the meso-structural changes, which are controlled by the interactions between the waste rocks and the cemented tailing paste.

scholarly journals IMPROVEMENT OF MICROMERITIC, COMPRESSIBILITY AND SOLUBILITY CHARACTERISTICS OF LINEZOLID BY CRYSTALLO-CO-AGGLOMERATION TECHNIQUE

2017 ◽  
Vol 9 (4) ◽  
pp. 47 ◽  
Author(s):  
Atul M. Kadam ◽  
Shitalkumar S. Patil
Keyword(s):  
Drug Release ◽  
Methyl Cellulose ◽  
Mechanical Deformation ◽  
Angle Of Repose ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Fourier Transformation Infrared Spectroscopy ◽  
Time Required ◽  
Good Flow

Objective: The purpose of current study was to improve physicochemical properties such as micrometric, compressibility and solubility of linezolid (LNZ) by preparing crystallo-co-agglomerates (CCA) in the presence of polymer for the enhancement of overall physicochemical performance.Methods: The process of agglomeration involves the use of dichloromethane (DCM) as a good solvent and chloroform as bridging liquid were used to prepare agglomerates. Agglomerates were characterised in the solid state using several techniques such as Scanning electronic microscopy(SEM), Fourier transformation infrared spectroscopy (FTIR), X-ray powder diffraction analysis (XRPD) The agglomerates obtained were evaluated for micrometric, mechanical, deformation, compressibility and drug release properties.Results: It was found that micrometric properties and dissolution characteristics of agglomerates were significantly improved than that of pure linezolid. Solubility was found to be increased than pure linezolid. The solubility of crystallo co-agglomerates was found an increase in 5 fold 3 fold and 3.7 fold for PVPK30 (0.5%), PVPK30 (0.25%) and PVPK30 (0.75%) respectively. The angle of repose for all batches was found between 22 ° to 30 °Carrs index was between 12.27±0.6 to 18.73±0.4 and Hausners ratio Near to 1, indicated good flow ability of agglomerates. The time required for drug release over a period of 60 min, is as LA1>LA2>LA3. LA3 shows fast drug release than LA1 and LA2, due to solubilization of drug due to more concentration of PVPK30 and less concentration of talc.Conclusion: Based on the above results, it was revealed that CCA of linezolid prepared with DCM and HPMC (Hydroxypropyl methyl cellulose)/PEG (Polyethylene glycol)/PVP (Polyvinylpyrrolidone) K30 exhibited improved micrometric properties, compressibility and in addition to improving solubility and dissolution rate.

New perspectives on Nephridiacanthus major (Acanthocephala: Oligacanthorhynchidae) collected from hedgehogs in Iran

2020 ◽  
Vol 94 ◽  
Author(s):  
O.M. Amin ◽  
M. Sharifdini ◽  
R.A. Heckmann ◽  
M. Zarean
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Phylogenetic Analysis ◽  
Chemical Analysis ◽  
Central Asia ◽  
Molecular Profile ◽  
X Ray ◽  
The Family ◽  
First Time ◽  
Scanning Electron

We describe morphological features not previously reported for this old acanthocephalan Nephridiacanthus major (Bremser, 1811 in Westrumb, 1821) Golvan, 1962 first described over 200 years ago. Our specimens were collected from long-eared hedgehog Hemiechinus auritus (Gmelin, 1770) (Erinaceidae) in Iran. We compare the morphometrics of our material with others previously reported from the same host in Iran, Russia, central Asia and Europe. Our specimens had markedly smaller proboscides, proboscis hooks and lemnisci than those reported from Russia and central Asia, but comparable measurements of other structures with specimens previously described from other collections. We document our new observations with scanning electron microscopy features not previously demonstrable by other observers and provide a chemical analysis of proboscis hooks using energy-dispersive X-ray analysis for the first time. The molecular profile of this acanthocephalan, based on 18S rDNA and cox1 genes, was generated for the first time. The phylogenetic analysis showed that N. major is placed in a clade of the family Oligacanthorhynchidae, well separated from the families Moniliformidae and Gigantorhynchidae.

scholarly journals Automated Dental Identification with Lowest Cost Path-Based Teeth and Jaw Separation

2016 ◽  
Vol 22 (2) ◽  
pp. 44-56 ◽  
Author(s):  
Jan-Vidar Ølberg ◽  
Morten Goodwin
Keyword(s):  
High Stability ◽  
Distance Measure ◽  
State Of The Art ◽  
Test Set ◽  
X Ray ◽  
Dental Identification ◽  
Verification Process ◽  
Stability And Accuracy ◽  
New System ◽  
Dental Work

Abstract Teeth are some of the most resilient tissues of the human body. Because of their placement, teeth often yield intact indicators even when other metrics, such as finger prints and DNA, are missing. Forensics on dental identification is now mostly manual work which is time and resource intensive. Systems for automated human identification from dental X-ray images have the potential to greatly reduce the necessary efforts spent on dental identification, but it requires a system with high stability and accuracy so that the results can be trusted. This paper proposes a new system for automated dental X-ray identification. The scheme extracts tooth and dental work contours from the X-ray images and uses the Hausdorff-distance measure for ranking persons. This combination of state-of-the-art approaches with a novel lowest cost path-based method for separating a dental X-ray image into individual teeth, is able to achieve comparable and better results than what is available in the literature. The proposed scheme is fully functional and is used to accurately identify people within a real dental database. The system is able to perfectly separate 88.7% of the teeth in the test set. Further, in the verification process, the system ranks the correct person in top in 86% of the cases, and among the top five in an astonishing 94% of the cases. The approach has compelling potential to significantly reduce the time spent on dental identification.

scholarly journals Kinetic Modeling and Mechanisms of Manganese Removal from Alkaline Mine Water Using a Pilot Scale Column Reactor

Minerals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 99
Author(s):  
Shigeshi Fuchida ◽  
Shota Tajima ◽  
Takuro Nishimura ◽  
Chiharu Tokoro
Keyword(s):  
Kinetic Modeling ◽  
Mine Water ◽  
Pilot Scale ◽  
Silica Sand ◽  
Edge Structure ◽  
Column Reactor ◽  
Molar Ratios ◽  
Manganese Removal ◽  
Water Ph ◽  
Xanes Analysis

Manganese (Mn) is a major element in various aqueous and soil environments that is sometimes highly concentrated in mine water and other mineral processing wastewater. In this study, we investigated Mn removal from alkaline mine water (pH > 9) with an Mn-coated silica sand packed into a pilot-scale column reactor and examined the specific reaction mechanism using X-ray absorption near-edge structure (XANES) analysis and geochemical kinetic modeling. The kinetic effect of dissolved Mn(II) removal by birnessite (δ-Mn(IV)O2) at pH 6 and 8 was evaluated at different Mn(II)/Mn(IV) molar ratios of 0.1–10. Our results confirmed the positive effect of the presence of δ-MnO2 on the short-term removal (60 min) of dissolved Mn. XANES analysis results revealed that δ-MnO2 was more abundant than Mn(III)OOH in the reactor, which may have accumulated during a long-term reaction (4 months) after the reactor was turned on. A gradual decrease in dissolved Mn(II) concentration with depth was observed in the reactor, and comparison with the kinetic modeling result confirmed that δ-MnO2 interaction was the dominant Mn removal mechanism. Our results show that δ-MnO2 contents could play a significant role in controlling Mn removability from mine water in the reactor.

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