Influence of Fuel Level on Properties, Productivity, and Mineralogy of Russian Vanadiferous Titanomagnetite Sinter

The influence of fuel level on Russian vanadiferous titanomagnetite sinter properties, productivity, and mineralogy are researched by sintering pot testing, metallographic microscopy, scanning electron microscopy analysis, and energy dispersive spectrometer (SEM-EDS) analysis. A comprehensive index is evaluated in conjunction with the same indexes and significance coefficient as that in the Panzhihua Iron and Steel Group. Results show that with the increasing fuel level from 3.5% to 6.0%, flame front speed, yield, tumbling test index (TI), and productivity, all first increase and then decrease. The low temperature reduction degradation index (RDI+3.15) and softening zone (ΔT) gradually increase while the RI and starting temperature of softening (T10), and ending temperature of softening (T40) decrease with increasing fuel levels from 3.5% to 6.0%. With the increase of fuel level from 3.5% to 6.0%, the content of FeO, SiO2, and MgO increase, while TiO2 shows a decrease. For the same increase in fuel level, the number of pores and calcium ferrite and hematite decrease but the silicate increases. In addition, in the fuel level range of 3.5% to 5.5%, magnetite correspondingly increases but then shows a drop after 5.5%. Moreover, when the fuel level increases to greater than 5.0%, FeOx and fayalite quickly increase and a small amount of metallic iron appears under the fuel level of 6.0%. Overall, the optimal fuel level under current production conditions and indicator selection is 4.0%.

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Trace Element Detection In Particle X-Ray Spectrum

Microscopy and Microanalysis ◽

10.1017/s1431927600011399 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 901-902

Author(s):

John A. Small

Keyword(s):

X Ray ◽

Minor Elements ◽

Elemental Concentrations ◽

Eds Analysis ◽

Electron Microscopy Analysis ◽

Microscopy Analysis ◽

Counting Statistics ◽

Automated Scanning ◽

Individual Particles ◽

Concentration Levels

One of the main goals of automated scanning electron microscopy analysis (ASEM) of particles is to provide macroscopic phase and compositional information on particle populations based on the energy dispersive x-ray spectrometry, EDS, analysis of several hundred to several thousand individual particles from the sample. The selection and identification of the various elemental groupings is often accomplished by applying techniques for grouping data, such as multivariate or cluster analysis methods, to characteristic x-ray intensities or normalized elemental concentrations. Particle groupings are often based on major and minor elements with concentrations greater than about 1-2 wt. percent. At these concentration levels, the peak-to-background ratios for the characteristic x-ray peaks are sufficiently large that in the absence of severe peak overlaps the elements can be easily identified even in spectra with poor counting statistics. Additional refinement in particle groupings may be possible if reliable information can be obtained on the trace elements present in particles at less than about 1-2 wt.%.

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Volcanic glass properties from 1459 C.E. volcanic event in South Pole ice core dismiss Kuwae caldera as a potential source

Scientific Reports ◽

10.1038/s41598-019-50939-x ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 6

Author(s):

Laura H. Hartman ◽

Andrei V. Kurbatov ◽

Dominic A. Winski ◽

Alicia M. Cruz-Uribe ◽

Siwan M. Davies ◽

...

Keyword(s):

Volcanic Eruption ◽

Energy Dispersive Spectrometer ◽

Ice Core ◽

Ice Cores ◽

Volcanic Glass ◽

South Pole ◽

Volcanic Event ◽

Electron Microscopy Analysis ◽

Microscopy Analysis ◽

Future Work

Abstract A large volcanic sulfate increase observed in ice core records around 1450 C.E. has been attributed in previous studies to a volcanic eruption from the submarine Kuwae caldera in Vanuatu. Both EPMA–WDS (electron microprobe analysis using a wavelength dispersive spectrometer) and SEM–EDS (scanning electron microscopy analysis using an energy dispersive spectrometer) analyses of five microscopic volcanic ash (cryptotephra) particles extracted from the ice interval associated with a rise in sulfate ca. 1458 C.E. in the South Pole ice core (SPICEcore) indicate that the tephra deposits are chemically distinct from those erupted from the Kuwae caldera. Recognizing that the sulfate peak is not associated with the Kuwae volcano, and likely not a large stratospheric tropical eruption, requires revision of the stratospheric sulfate injection mass that is used for parameterization of paleoclimate models. Future work is needed to confirm that a volcanic eruption from Mt. Reclus is one of the possible sources of the 1458 C.E. sulfate anomaly in Antarctic ice cores.

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Study on the Remediation of Cd Pollution by the Biomineralization of Urease-Producing Bacteria

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16020268 ◽

2019 ◽

Vol 16 (2) ◽

pp. 268 ◽

Cited By ~ 16

Author(s):

Xingqing Zhao ◽

Min Wang ◽

Hui Wang ◽

Ding Tang ◽

Jian Huang ◽

...

Keyword(s):

Contaminated Soil ◽

Contaminated Soils ◽

Phylogenetic Trees ◽

Energy Dispersive Spectrometer ◽

Toxic Metal ◽

Environmental Safety ◽

Removal Rates ◽

Exchangeable Fraction ◽

Electron Microscopy Analysis ◽

Microscopy Analysis

Cadmium (Cd) is a highly toxic metal that can affect human health and environmental safety. The purpose of this study was to research the removal of Cd from an environmental perspective. In this article, four highly urease-active strains (CZW-2, CZW-5, CZW-9 and CZW-12) were isolated from an abandoned mine and their phylogenetic trees were analyzed. The maximum enzyme activities, the mineralized precipitate and the removal rates of these strains were compared. The results showed that CZW-2 had the highest urease activity at 51.6 U/mL, and the removal rates of CZW-2, CZW-5, CZW-9 and CZW-12 after 120 h were 80.10%, 72.64%, 76.70% and 73.40%, with an initial concentration of Cd of 2 mM in the Cd precipitation experiments. XRD (X-ray diffractometer), EDS (Energy dispersive spectrometer) and FTIR (Fourier transform infrared spectroscopy) analysis indicated that the mineralized precipitate was CdCO3. SEM (Scanning electron microscopy) analysis revealed that the diameter of the oval-shaped mineralized product ranked from 0.5 to 2 μm. These strains were used to remedy Cd-contaminated soil, and five different fractions of Cd were measured. Compared with the control, the results of spraying pre-cultured strains containing 2% urea to remove Cd from contaminated soils showed that the exchangeable fraction of Cd decreased by 53.30%, 27.78%, 42.54% and 53.80%, respectively, whereas the carbonate-bound fraction increased by 55.42%, 20.27%, 39.67% and 34.36%, respectively, after one month. These data show that these strains can effectively reduce the bioavailability and mobility of Cd in contaminated soils. The results indicate that biomineralization based on the decomposition of substrate urea can be applied to remedy heavy contaminated soil and water.

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Material analysis techniques using the ion mill

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167639 ◽

1996 ◽

Vol 54 ◽

pp. 1034-1035

Author(s):

J. P. Benedict ◽

R. M. Anderson ◽

S. J. Klepeis

Keyword(s):

Polished Surface ◽

Surface Material ◽

Analysis Techniques ◽

Material Analysis ◽

Optical Inspection ◽

Electron Microscopy Analysis ◽

Microscopy Analysis ◽

Argon Ions ◽

The Impact ◽

Scanning Electron

Ion mills equipped with flood guns can perform two important functions in material analysis; they can either remove material or deposit material. The ion mill holder shown in Fig. 1 is used to remove material from the polished surface of a sample for further optical inspection or SEM ( Scanning Electron Microscopy ) analysis. The sample is attached to a pohshing stud type SEM mount and placed in the ion mill holder with the polished surface of the sample pointing straight up, as shown in Fig 2. As the holder is rotating in the ion mill, Argon ions from the flood gun are directed down at the top of the sample. The impact of Argon ions against the surface of the sample causes some of the surface material to leave the sample at a material dependent, nonuniform rate. As a result, the polished surface will begin to develop topography during milling as fast sputtering materials leave behind depressions in the polished surface.

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Transmission electron microscopy analysis of planar faults on (001) planes in MoSi2single crystals

Philosophical Magazine A ◽

10.1080/01418610208240063 ◽

2002 ◽

Vol 82 (14) ◽

pp. 2737-2754 ◽

Cited By ~ 2

Author(s):

Susanne Guder ◽

Martin Bartsch ◽

Ulrich Messerschmidt

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Transmission Electron Microscopy Analysis ◽

Transmission Electron ◽

Electron Microscopy Analysis ◽

Microscopy Analysis

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Effects of Various Antioxidant Pretreatment Modalities on Adhesion to Sound and Caries-Affected Dentin: An In Vitro Study

Journal of Advanced Oral Research ◽

10.1177/2320206821997985 ◽

2021 ◽

pp. 232020682199798

Author(s):

Beyza Unalan Degirmenci ◽

Alperen Degirmenci ◽

Emine Kara

Keyword(s):

Bond Strength ◽

In Vitro Study ◽

Natural Antioxidants ◽

Microtensile Bond Strength ◽

Mandibular Molar ◽

Electron Microscopy Analysis ◽

Molar Teeth ◽

Microscopy Analysis ◽

Two Parameters

Aim: Natural antioxidants were offered as the answer of dentin adhesion issue. The aim of this study is to investigate the effects of proanthocyanidin and lycopene as pretreatment agents on the sound and caries-affected dentin surface on microtensile bond strength and microleakage. Materials and Methods: This study was designed as in vitro because of that 84 mandibular molar teeth were collected. Forty-two of the included teeth were carious teeth, while the other 42 were without caries. Sixty of them were used for microleakage and 24 for microtensile bond strength testing and scanning electron microscopy analysis. The samples were divided into six subgroups randomly according to dentin pretreatments: 5% proanthocyanidin, 5% lycopene, and no antioxidant application. After the restorative procedures, samples were attached to the microtensile tester. Samples were subjected to tensile stress in the load cell until they broke at a speed of 0.5 mm per min. Microtensile bond strength (µTBS) and microleakage test data were analyzed with two-way analysis of variance, Bonferroni correction, and Tamhane’s T2 tests. Results: Two-way variance analysis showed that dentin pretreatment applications, dentin substrate, and the interaction between these two parameters had statistically significant effects on µTBS values ( P < .001). There was no difference between dentin pretreatment applications in terms of microleakage scores ( P > .05). Conclusion: The application of dentin pretreatment with proanthocyanidin is a successful procedure that increases the bond strength in both dentin substrate, while pretreatment with lycopene in caries-affected dentin reduces it.

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Antiparasitic Properties of Cardiovascular Agents against Human Intravascular Parasite Schistosoma mansoni

Pharmaceuticals ◽

10.3390/ph14070686 ◽

2021 ◽

Vol 14 (7) ◽

pp. 686

Author(s):

Raquel Porto ◽

Ana C. Mengarda ◽

Rayssa A. Cajas ◽

Maria C. Salvadori ◽

Fernanda S. Teixeira ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Screening Strategy ◽

Early Infection ◽

Global Public Health ◽

Parasitic Worm ◽

Electron Microscopy Analysis ◽

Health Significance ◽

Microscopy Analysis

The intravascular parasitic worm Schistosoma mansoni is a causative agent of schistosomiasis, a disease of great global public health significance. Praziquantel is the only drug available to treat schistosomiasis and there is an urgent demand for new anthelmintic agents. Adopting a phenotypic drug screening strategy, here, we evaluated the antiparasitic properties of 46 commercially available cardiovascular drugs against S. mansoni. From these screenings, we found that amiodarone, telmisartan, propafenone, methyldopa, and doxazosin affected the viability of schistosomes in vitro, with effective concentrations of 50% (EC50) and 90% (EC90) values ranging from 8 to 50 µM. These results were further supported by scanning electron microscopy analysis. Subsequently, the most effective drug (amiodarone) was further tested in a murine model of schistosomiasis for both early and chronic S. mansoni infections using a single oral dose of 400 mg/kg or 100 mg/kg daily for five consecutive days. Amiodarone had a low efficacy in chronic infection, with the worm and egg burden reduction ranging from 10 to 30%. In contrast, amiodarone caused a significant reduction in worm and egg burden in early infection (>50%). Comparatively, treatment with amiodarone is more effective in early infection than praziquantel, demonstrating the potential role of this cardiovascular drug as an antischistosomal agent.

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Impact Resistance of Epoxy Composites Reinforced with Amazon Guaruman Fiber: A Brief Report

Polymers ◽

10.3390/polym13142264 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2264

Author(s):

Raphael H. M. Reis ◽

Fabio C. Garcia Filho ◽

Larissa F. Nunes ◽

Veronica S. Candido ◽

Alisson C. R. Silva ◽

...

Keyword(s):

Fiber Composite ◽

Impact Resistance ◽

Fiber Composites ◽

Epoxy Composites ◽

Impact Performance ◽

Electron Microscopy Analysis ◽

Ballistic Properties ◽

Microscopy Analysis ◽

Izod Impact ◽

The Impact

Fibers extracted from Amazonian plants that have traditionally been used by local communities to produce simple items such as ropes, nets, and rugs, are now recognized as promising composite reinforcements. This is the case for guaruman (Ischinosiphon körn) fiber, which was recently found to present potential mechanical and ballistic properties as 30 vol% reinforcement of epoxy composites. To complement these properties, Izod impact tests are now communicated in this brief report for similar composites with up to 30 vol% of guaruman fibers. A substantial increase in impact resistance, with over than 20 times the absorbed energy for the 30 vol% guaruman fiber composite, was obtained in comparison to neat epoxy. These results were statistically validated by Weibull analysis, ANOVA, and Tukey’s test. Scanning electron microscopy analysis disclosed the mechanisms responsible for the impact performance of the guaruman fiber composites.

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