1,021 results on '"Scanning microscopy"'
Search Results
2. Hatching Egg Sanitizers Based on Essential Oils: Microbiological Parameters, Hatchability, and Poultry Health.
- Author
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Oliveira, Gabriel da Silva, McManus, Concepta, Santos, Pedro Henrique Gomes de Sá, de Sousa, Davi Emanuel Ribeiro, Jivago, José Luiz de Paula Rôlo, de Castro, Márcio Botelho, and dos Santos, Vinícius Machado
- Subjects
ESSENTIAL oils ,GARLIC ,INHIBITION (Chemistry) ,BASIL ,NATURAL products - Abstract
Background: Eggshell contamination threatens the viability of hatching eggs. This contamination can be caused by harmless, opportunistic, or pathogenic bacteria. Although necessary, the use of synthetic antibiotics to treat eggshells can present several significant problems: They can be toxic and damage the shell, and, most worryingly, they can lead to bacterial resistance. Faced with these challenges, the objective of this research was to create and test a sanitizing plan for hatching eggs using essential oils derived from Citrus aurantifolia (CAEO), Ocimum basilicum (OBEO), or Allium sativum (ASEO). Methods: Sanitizing solutions containing specific concentrations of these essential oils were prepared, and their antimicrobial properties and contributions to poultry safety and hatching parameters were investigated. Results: The bacterial load was reduced in eggshells sanitized with essential oils, and the degree of bacterial inhibition, along with their safety profile, may be directly related to optimal hatchability rates, lower incidences of contaminated dead embryos, and the hatching of healthy chicks. Conclusions: Together, these results reinforce the importance of essential oils in the development of effective and safe treatments for managing hatching eggs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Analysis of Spatial Distributions of the Number of Photon Counts in Fluorescence Fluctuation Spectroscopy.
- Author
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Skakun, V. V., Hink, M. A., and Apanasovich, V. V.
- Subjects
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GREEN fluorescent protein , *PHOTON counting , *NUMERICAL analysis , *SPECTRAL imaging , *MICROSCOPY - Abstract
A method is proposed for analysis of the photon-count number distributions (PCD) calculated over the space (pixels) of a stack of fluorescent images obtained in the process of a scanning measurement in fluorescence fluctuation spectroscopy which makes it possible to determine the characteristic brightness and number of molecules of the material being studied. The method is applicable to ergodic systems and is based on a theory of the analysis of Photon Counting Histograms (PCH) developed for single-point measurements. The method is tested on experimentally obtained images of a green fluorescent protein. The obtained results are compared with the results of a single-point experiment and the N&B (Number and Brightness) method, which is most often used for numerical analysis of a stack of fluorescent images obtained in scanning experiments. The estimates of the characteristic brightness and number of molecules of the studied substance are in good agreement with estimates obtained with the aid of the methods of analysis used in this region, which makes it possible to conclude that the theory of the PCH method can be used for analyzing spatial PCDs calculated on the basis of a stack of images. The developed method makes it possible to obtain estimates of the studied parameters based on a selected subregion of a single frame of the image. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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4. Antibacterial Dental Adhesive Containing Cetylpyridinium Chloride Montmorillonite.
- Author
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Okazaki, Yohei, Nakamori, Kiichi, Yao, Chenmin, Ahmed, Mohammed H., Mercelis, Benjamin, Nagaoka, Noriyuki, Maruo, Yukinori, Yoshida, Yasuhiro, Abe, Yasuhiko, Van Meerbeek, Bart, and Yoshihara, Kumiko
- Subjects
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BOND strengths , *DENTAL materials , *CETYLPYRIDINIUM chloride , *DENTAL caries , *PERIODONTAL disease - Abstract
Oral bacteria cause tooth caries and periodontal disease. Much research is being conducted to prevent both major oral diseases by rendering dental materials' antimicrobial potential. However, such antimicrobial materials are regarded as 'combination' products and face high hurdles for regulatory approval. We loaded inorganic montmorillonite with the antimicrobial agent cetylpyridinium chloride, referred to below as 'CPC-Mont'. CPC-Mont particles in a 1, 3 and 5 wt% concentration were added to the considered gold-standard self-etch adhesive Clearfil SE Bond 2 ('CSE2'; Kuraray Noritake) to render its antibacterial potential (CSE2 without CPC-Mont served as control). Besides measuring (immediate) bonding effectiveness and (aged) bond durability to dentin, the antibacterial activity against S. mutans and the polymerization-conversion rate was assessed. Immediate and aged bond strength was not affected by 1 and 3 wt% CPC-Mont addition, while 5 wt% CPC-Mont significantly lowered bond strength and bond durability. The higher the concentration of the antimicrobial material added, the stronger the antimicrobial activity. Polymerization conversion was not affected by the CPC-Mont addition in any of the three concentrations. Hence, adding 3 wt% CPC-Mont to the two-step self-etch adhesive rendered additional antimicrobial potential on top of its primary bonding function. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Development and Assessment of Multiple Illumination Color Fourier Ptychographic Microscopy for High Throughput Sample Digitization.
- Author
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Gilley, Patrik, Zhang, Ke, Abdoli, Neman, Sadri, Youkabed, Adhikari, Laura, Fung, Kar-Ming, and Qiu, Yuchen
- Subjects
- *
MICROSCOPY , *DIGITIZATION , *CELL nuclei , *SCANNING systems , *LIGHTING , *CELL imaging , *SPATIAL resolution - Abstract
In this study, we proposed a multiplexed color illumination strategy to improve the data acquisition efficiency of Fourier ptychography microscopy (FPM). Instead of sequentially lighting up one single channel LED, our method turns on multiple white light LEDs for each image acquisition via a color camera. Thus, each raw image contains multiplexed spectral information. An FPM prototype was developed, which was equipped with a 4×/0.13 NA objective lens to achieve a spatial resolution equivalent to that of a 20×/0.4 NA objective lens. Both two- and four-LED illumination patterns were designed and applied during the experiments. A USAF 1951 resolution target was first imaged under these illumination conditions, based on which MTF curves were generated to assess the corresponding imaging performance. Next, H&E tissue samples and analyzable metaphase chromosome cells were used to evaluate the clinical utility of our strategy. The results show that the single and multiplexed (two- or four-LED) illumination results achieved comparable imaging performance on all the three channels of the MTF curves. Meanwhile, the reconstructed tissue or cell images successfully retain the definition of cell nuclei and cytoplasm and can better preserve the cell edges as compared to the results from the conventional microscopes. This study initially validates the feasibility of multiplexed color illumination for the future development of high-throughput FPM scanning systems. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. NON-INVASIVE FORENSIC EXAMINATION OF INSCRIPTIONS IN A HISTORICAL DOCUMENT AS AN ATTEMPT TO EVALUATE THE DIVERSITY OF THE COMMERCIAL OFFER OF INKS.
- Author
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CIEŚLA, Rafał
- Subjects
REGIONAL development ,RAMAN spectroscopy ,HISTORICAL source material ,INDIVIDUAL differences ,GERMAN history - Abstract
In the history of the German state, the world-wide economic crisis (1929-1939) probably also had an impact on the availability of inks. The research aimed to find out whether it is possible to discriminate between inks and determine the prevalence of ink manufacturers in a specific area, which, in statistical terms, could provide insight into the development of regional ink producers. The research covered selected inscriptions in ink written in a Diary from a small geographical area. Ink examination was carried out using non-invasive VIS-NIR and RS spectroscopic methods involving a statistical approach. The obtained results allowed effective discrimination of the inks and divided them into several groups. Research has shown that iron-gall inks from several ink manufacturers were used to prepare the entries in the Diary. It cannot be ruled out that the differences in individual inks resulted from technological changes in their production process. Additionally, the research revealed a multitude of entries made with iron-gall inks, which may testify to the development of small-scale production of iron-gall inks confined to one geographical area. This type of historical document may constitute a forgery in whole or in specific parts of the inscriptions executed to falsify significant facts, therefore it is an object of interest of forensic science. The non-invasive VIS-NIR and RS spectroscopic methods supported by statistical approach should continue to develop to become an alternative and reliable solution offering great potential in forensic examination of inks. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Exploring microscopic pollen morphology in herbaceous Flora: Insights and analysis using scanning electron microscopy.
- Author
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Aziza, Nozimova, Khaydarov, Khislat, Zamira, Djumayeva, Ochilov, Ulugbek, and Dilshod, Muminov
- Abstract
Microscopic techniques can be applied to solve taxonomic problems in the field of plant systematic and are extremely versatile in nature. This study was focused on the new approaches to visualizing the imaging, tool to cover the micro‐structural techniques applied to the pollen study of flowers. The current research was proposed to evaluate microscopic pollen morphological attributes using light and scanning electron microscopy of herbaceous flora from Samarkand, Uzbekistan. A total of 13 herbaceous species, classified into 11 different families were collected, pressed, and identified, and then acetolyzed their pollen to visualize under light and scanning electron microscopy. Herbaceous flora can be characterized by small to very large‐sized pollen morphotypes presenting four types of pollen shapes, prolate spheroidal (six species), spheroidal (three species) and prolate and oblate (two species each). The polar diameter and equatorial distance were calculated maximum in Hibiscus syriacus 110.55 and 111.2 μm respectively. Pollen of six different types was found namely tricolporate pollen observed in seven species, tricolpate and pantoporate in two species each, sulcate in Gagea olgae and hexacolpate pollen was examined in Salvia rosmarinus. Exine ornamentation of pollen was examined tectate perforate, verrucate‐reticulate, micro‐reticulate, reticulate, reticulate‐cristatum, gemmate‐echinate, echinate‐perforate, perforate‐striate, rugulate, rugulate‐striate, bi‐reticulate, reticulate‐perforate and perforate‐micro‐reticulate showing great variations. Exine thickness was noted highest for Rosa canina 2.9 μm and minimum in Punica granatum 0.65 μm. This study of pollen imaging visualization of herbaceous flora contributes to the opportunity for the taxonomic evaluation of and fills knowledge gaps in studies of herbaceous flora identification using classical microscopic taxonomic tools for their accurate identification. Research Highlights: Pollen in unexplored herbaceous flora of the Samarkand region was studied with light and scanning electron microscopic pollen study.There is a high variation in observed pollen micromorphological characters.Pollen microscopic morphology has important taxonomic value for the identification of herbaceous species. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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8. Opuntioideae cactus stem Bioimaging analysis: Bridging taxonomy and antimicrobial research.
- Author
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Almalki, Waleed Hassan
- Abstract
This study presents a comprehensive scanning electron microscopy (SEM) analysis of Opuntioideae cactus stems indigenous to the arid regions of Saudi Arabia, elucidating their intricate microstructural features. The findings not only advance taxonomic understanding by aiding in species differentiation but also reveal the antimicrobial potential of these cacti, highlighting their significance as valuable natural resources for both ecological and pharmaceutical applications. The present study is aimed to present the stem epidermal anatomical description of Opuntioideae (Cactaceae) belonging to genus Opuntia (five Species), Cylindropuntia (two Species), and Austrocylindropuntia (one Species) as tool for systematic identification. Stem epidermal anatomical features represent here are epidermal cells, stomatal complex, subsidiary cells, and trichomes findings was observed using light microscope and SEM. The stem epidermal sections were made by heating in test tube containing lactic acid and nitric acid protocol. In anatomical findings, irregular, zigzag, wavy, and polygonal epidermal cells with sinuate, sinuous, and straight anticlinal walls were observed. Quantitatively minimum length (28.05 ± 2.05 μm) and width (23.15 ± 3.41 μm) of epidermal cells were noted in Cylindropuntia kleiniae. Paracytic type of stomata present was observed in all species with kidney‐shaped guard cell present in six species, and in Opuntia macrocentra and Austrocylindropuntia subulata, dumbbell‐shaped guard cells were observed. The largest length of stomata (53.25 ± 2.05 μm) and width of stomata (35.10 ± 5.19 μm) were observed in Opuntia monacantha. In present research work, stem anatomical features show many diverse characters are of special attention for plant taxonomist for the correct identification and provide baseline for further study in subfamily Opuntiodeae. Research Highlights: The intricate microstructures of Opuntioideae cactus stems.Investigating the antimicrobial potential of compounds found within Opuntioideae cactus stems.Correlations between the unique structural features observed through SEM and the antimicrobial activity of Opuntioideae cactus stem extracts. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Model of Static Destruction of a Copper Conductor during Current Overload.
- Author
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Nedobitkov, A. I. and Abdeyev, B. M.
- Abstract
The results of experimental and theoretical studies of the formation of a crack in a copper conductor under the influence of current overload are presented. The conductor was examined using a JSM-6390L scanning electron microscope. A refined mathematical model of the static stress–strain state and destruction of a copper rod under conditions of inelastic bending at temperatures up to 700°C has been obtained. The limiting values of the bending moment and curvature of the copper conductor, causing its rupture after the formation of a crack, have been determined. The calculation algorithm has been brought to the final analytical dependences, allowing them to be used when conducting forensic fire-technical examination or designing electrical wiring. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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10. Sand washing of oil spill–affected beaches using concentrated β-glucans obtained from residual baker's yeast
- Author
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Úrsula Navarro-Abarca, Mara Ayala-Gonzales, Paola Jorge-Montalvo, and Lizardo Visitación-Figueroa
- Subjects
Infrared spectrophotometry ,Scanning microscopy ,Surface tension ,Waste utilization ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Valorization of residual yeast of the bakery industry for use in the remediation of oil-contaminated soils as an emulsifier is a biocompatible and effective process that will reduce environmental pollution. The aim of this study was to use concentrated β-glucan obtained from residual baker's yeast, Saccharomyces cerevisiae, as an emulsifier to remove total petroleum hydrocarbons (TPH) from the contaminated sands of two beaches affected by the oil spill that occurred in January 2022 north of Lima, Peru. The extraction and concentration of β-glucan from sand were performed at a pilot scale using autolysis with 3 % sodium chloride, temperature elevation, treatment with organic solvents and water, hydrolysis via proteases, and vacuum filtration. The chemical composition and functional properties of concentrated β-glucan were evaluated to determine its quality and efficacy. In addition, the values of TPH removal efficiency obtained using concentrated β-glucan, water, and the commercial emulsifier Tween-80 were compared. The mass recovery of concentrated β-glucan was 5.59 %, with a β-glucan content of 38.60 %. The efficiency of ex-situ removal of TPH from hydrocarbon-impacted sands containing 78323 mg/kg of TPH reached 50 % and 70 % when the concentrated β-glucan concentrations used were 70.3 % and 80.3 %, respectively. These efficiency values are higher than those obtained when water was used for TPH removal but lower than those obtained when Tween-80 was used for TPH removal.
- Published
- 2024
- Full Text
- View/download PDF
11. Combined flat-field and frequency filter approach to correcting artifacts of multichannel two-photon microscopy.
- Author
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Knapp, Thomas, Lima, Natzem, Daigle, Noelle, Duan, Suzann, Merchant, Juanita L., and Sawyer, Travis W.
- Subjects
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STANDARD deviations , *MICROSCOPY , *ERROR-correcting codes , *IMAGE compression - Abstract
Significance: Multiphoton microscopy (MPM) is a useful biomedical imaging tool for its ability to probe labeled and unlabeled depth-resolved tissue biomarkers at high resolution. Automated MPM tile scanning allows for whole-slide image acquisition but can suffer from tile-stitching artifacts that prevent accurate quantitative data analysis. Aim: We have investigated postprocessing artifact correction methods using ImageJ macros and custom Python code. Quantitative and qualitative comparisons of these methods were made using whole-slide MPM autofluorescence and secondharmonic generation images of human duodenal tissue. Approach: Image quality after artifact removal is assessed by evaluating the processed image and its unprocessed counterpart using the root mean square error, structural similarity index, and image histogram measurements. Results: Consideration of both quantitative and qualitative results suggest that a combination of a custom flat-field-based correction and frequency filtering processing step provide improved artifact correction when compared with each method used independently to correct for tiling artifacts of tile-scan MPM images. Conclusions: While some image artifacts remain with these methods, further optimization of these processing steps may result in computational-efficient methods for removing these artifacts that are ubiquitous in large-scale MPM imaging. Removal of these artifacts with retention of the original image information would facilitate the use of this imaging modality in both research and clinical settings, where it is highly useful in collecting detailed morphologic and optical properties of tissue. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
12. Taxonomic studies based on leaf epidermal microanatomy using high‐resolution microscopy in Lamiaceous species and their antimicrobial effects.
- Author
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Ameen, Fuad
- Abstract
The knowledge of essential oil antimicrobial activity of Lamiaceous species is assessed to describe its effects. The comprehensive foliar trichomes and stomatal morphology of the leaves of essential oil‐bearing plants from the family Lamiaceae revealed diverse antimicrobial properties. The aim of this study was to investigate the foliar anatomical traits of 19 Lamiaceous taxa belonging to different tribes using light and scanning electron microscopy to correctly diagnose the species. The microanatomy of the foliar epidermis, trichomes diversity, and the stomatal apertural complex was visualized. Quantitative measurements were noted to describe the variations and the qualitative aspects for example, polygonal shape epidermal cells were examined. The stomatal aperture of four types and trichomes appendages both non‐glandular and glandular was identified. Significant variation was found in both quantitative and qualitative traits, including unique ornamentation on the trichomes. The taxonomic key was constructed for accurate identification using qualitative morpho‐structural traits. The outcomes of this research explored taxonomically to accurately identify the Lamiaceous species using anatomical characters. This study will provide provides the ecological adaptation linked to evolutionary traits of leaf surfaces that evolve with time to adapt the harsh environmental conditions. Research Highlights: Investigated foliar anatomical traits of 19 Lamiaceous speciesThe anatomy and antimicrobial activity of essential oil yielding Lamiaceae species.SEM revealed diverse aspects including peculiar sculptured trichomesMicroscopic identification of different stomatal complex [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
13. Development and Assessment of Multiple Illumination Color Fourier Ptychographic Microscopy for High Throughput Sample Digitization
- Author
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Patrik Gilley, Ke Zhang, Neman Abdoli, Youkabed Sadri, Laura Adhikari, Kar-Ming Fung, and Yuchen Qiu
- Subjects
multiplexed illumination ,color FPM ,scanning microscopy ,Chemical technology ,TP1-1185 - Abstract
In this study, we proposed a multiplexed color illumination strategy to improve the data acquisition efficiency of Fourier ptychography microscopy (FPM). Instead of sequentially lighting up one single channel LED, our method turns on multiple white light LEDs for each image acquisition via a color camera. Thus, each raw image contains multiplexed spectral information. An FPM prototype was developed, which was equipped with a 4×/0.13 NA objective lens to achieve a spatial resolution equivalent to that of a 20×/0.4 NA objective lens. Both two- and four-LED illumination patterns were designed and applied during the experiments. A USAF 1951 resolution target was first imaged under these illumination conditions, based on which MTF curves were generated to assess the corresponding imaging performance. Next, H&E tissue samples and analyzable metaphase chromosome cells were used to evaluate the clinical utility of our strategy. The results show that the single and multiplexed (two- or four-LED) illumination results achieved comparable imaging performance on all the three channels of the MTF curves. Meanwhile, the reconstructed tissue or cell images successfully retain the definition of cell nuclei and cytoplasm and can better preserve the cell edges as compared to the results from the conventional microscopes. This study initially validates the feasibility of multiplexed color illumination for the future development of high-throughput FPM scanning systems.
- Published
- 2024
- Full Text
- View/download PDF
14. Thermoelectric effects in carbon nanostructures
- Author
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Harzheim, Achim, Briggs, George, Gehring, Pascal, and Mol, Jan
- Subjects
620 ,thermoelectrics ,2D materials ,scanning microscopy ,0D materials ,heat flow - Abstract
Heat from electrical devices, car engines, industrial processes and even our own body heat are an abundant, albeit difficult to harvest, energy source in today's society. As the extent of the climate crisis becomes clearer, recovering such waste heat can be an important step to design improved devices and reduce greenhouse gas emissions as well as the use of fossil fuels. Thermoelectric materials and devices are uniquely positioned to recover this waste heat and transform it to electricity due to their conversion characteristics and potentially small size. In addition, ever-increasing demands on computing power as well as further downscaling in chip sizes necessitates on-chip spot cooling and temperature sensing, which can be provided by thermoelectric devices. So far, whenever research in thermoelectrics seemed to be at a dead end, a new approach, such as for example most recently nanostructuring and reduced dimensionality, have reinvigorated the field. While this has lead to unprecedented advances in the figure of merit, now regularly reported above unity, thermoelectric devices are still lacking the required conversion efficiency to compete with conventional heat engines, leaving them an option mostly for niche applications. Particularly in low-dimensional devices and structures, theoretically predicted high and competitive efficiency values are hard to obtain due to environmental factors and inherent limits in device design. In this dissertation, influences on the thermoelectric properties of carbon nanostructures due to coupling configurations, defects, geometrical considerations and other local effects are studied. A first experiment investigates the power factor in C₆₀ molecules, contacted via electroburned graphene nanoconstrictions. The results suggest a threefold way to increase the achievable power factor in zero-dimensional structures: positioning the molecular energy levels close to the Fermi energy levels of the leads, ensuring the tunnel coupling is optimized for the desired operating temperature and, in order to achieve a maximum power factor, the tunnel couplings to the source and drain need to be equal. Building on these conclusions, a temperature dependent study of the power factor in graphene quantum dots was performed, suggesting that a quantum dot can work as a quantum heat valve especially when contacted by non-ideal heat conducting leads. Apart from highlighting the importance of leads that conduct heat well to achieve a high performance, the findings also again emphasize the potentially detrimental effect tunnel coupling has on the power factor. In order to analyse more localised effects, a Scanning Thermal Microscopy (SThM) approach was used to record thermoelectric maps (of both the Seebeck and Peltier effect) of graphene bow ties, revealing a geometrically dependent change in the Seebeck coefficient due to the impact of electron scattering at the graphene edges. This effect is exploited later to fabricate single-material graphene thermocouples that achieve an order of magnitude higher sensitivity than previously reported single-material metal thin film thermocouples. Lastly, Scanning Thermal Gate Microscopy (STGM) is developed, improving on the previously used SThM technique to achieve high resolution in thermovoltage maps at a fast scanning rate. STGM is then applied to graphene single-layer/bilayer junctions, demonstrating the influence of metallic contacts, layer thickness changes and local strain on the spatially distributed Seebeck coefficient in graphene. The effects studied in this dissertation are aimed at helping to further the understanding of local thermoelectric properties and opening the path to improve on current device design and performances as well as facilitating the elimination of parasitic noise caused by undesirable thermoelectric effects.
- Published
- 2020
15. High-Energy Transformations of Fossil Fuels in the Cement Industry.
- Author
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Szwed, Mirosław, Żukowski, Witold, Misztal, Krzysztof, and Kozłowski, Rafał
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FOSSIL fuel industries , *GREENHOUSE gases , *CEMENT plants , *SCANNING electron microscopes , *SCOTS pine - Abstract
The energy stored in fossil fuels is released through combustion and is a fundamental process in the production of cement. The negative aspect of this combustion is the emission of greenhouse gases and dust. This paper presents the results of a study conducted within a cement plant in Ożarów (south-eastern Poland). The chemical properties (selected elements) in the needles of Scots pine (Pinus sylvestris L.) were determined. The needle surface was scanned using a scanning electron microscope (SEM) and was characterised in terms of chemical composition through energy dispersive spectroscopy (EDS). The concentrations of selected analytes in the biennial needles formed the following descending sequence: Fe > Al > Mn > Zn > Cu > Pb > Cr > Ni. SEM/EDS microphotographs showed the presence of particles of varying shape, size and chemical composition indicative of anthropogenic origin. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
16. Valorisation of Zingiber officinale Roscoe postharvest residues as byproducts with antioxidant capacity
- Author
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Paola Jorge-Montalvo, Carlos Vílchez-Perales, and Lizardo Visitación-Figueroa
- Subjects
Agroindustry ,Bioactive compounds ,Infrared spectrophotometry ,Scanning microscopy ,Waste utilisation ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
During the postharvest phase of ginger, 2.6%–5% by weight of ginger rhizome residues are generated, which are disposed in landfills and constitute a continuous source of organic contamination causing serious environmental problems. The objective of this study was to valorise ginger postharvest residues (shoot, finger, slice, trunk, root, and rootles) from district Pichanaki (Peru) as dry powdered byproducts with an antioxidant capacity similar to that of rhizome. The nutrition composition, phenolic compounds, such as total phenolic content, total flavonoid content, 6-gingerol content, and 6-shogaol content, antioxidant capacity expressed by ferric reducing antioxidant power and IC50 of 2,2-diphenyl-1-picrylhydrazyl radical, surface changes, and structural morphology were evaluated. In addition, the dependent variables were correlated using the Pearson's matrix and principal component analysis (PCA). The results for shoot, finger, slice, and trunk residues showed similar phenolic compound contents and antioxidant capacities to those of rhizome, but similar results were not obtained for root and rootlet residues. These results were corroborated by analyses of surface and structural morphologies. The Pearson's matrix showed that the content of phenolic compounds correlated with the antioxidant capacity and carbohydrate content for the rhizome and residues, except for the root. The PCAshowed that residues that exhibited higher contents of starch grains with reserve functions such as shoot, finger, slice, and trunk were correlated with higher contents of phenolic compounds with antioxidant capacity, while residues with higher contents of crude fibre and ash with a support function exhibited a low antioxidant capacity. Thus, the shoot, finger, slice, and trunk residues, from district Pichanaki (Peru), can be valorised and reincorporated as byproducts in the ginger value chain. They are important for the food, cosmetic, and pharmaceutical industries.
- Published
- 2023
- Full Text
- View/download PDF
17. Antibacterial and Anti-biofilm Efficiency of Twenty Algerian Plants Essential Oils Against Resistant Acinetobacter baumannii.
- Author
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Ouslimani, Saida, Bendahou, Mourad, Abedelmounaim, Khadir, Benbelaid, Fethi, Mahdi, Fatma, Yassine Benziane, M., and Costa, Jean
- Subjects
- *
ESSENTIAL oils , *VEGETABLE oils , *GAS chromatography/Mass spectrometry (GC-MS) , *ACINETOBACTER baumannii , *MOLECULAR docking , *GAS chromatography - Abstract
The present study evaluated the antibacterial activity of twenty essential oils from Algerian plants against the multi-drug resistant (MDR), the extended-drug resistant (XDR), the pan-drug resistant (PDR) and the wild strains of Acinetobacter baumannii: a major human pathogen for which only a few effective treatments are nowadays available. Special attention was also given to their effect on A. baumannii biofilm formation. The chemical composition of the essential oils was determined by gas chromatography and gas chromatography-mass spectrometry analysis, while the antibacterial activity was determined by disc diffusion and microdilution broth sensitivity assays. Microscopic visualization highlighted the effect of the most active essential oils on biofilm formation. Molecular docking was performed to investigate the binding mode of imipenem, thymol and cinnamaldehyde against target proteins (PBP1, OMPA and IMP2). Eight of the twenty essential oils showed very good activities against resistant A.baumannii with inhibition zones greater than 20 mm. Ammoides verticillata essential oil recorded the lowest minimum inhibitory concentrations, biofilm inhibition and biofilm eradication concentrations values no more than 0.217 mg/mL, 0.48 mg/mL, and 0.48 mg/mL, respectively. A. verticillata and C. cassia not only inhibited biofilm formation but also weakened and dissolved pre-formed biofilms. The in-silico and in-vitro studies showed that phytochemical analogues, thymol and cinnamaldehyde had improved physicochemical characteristics, greater binding affinities and, a better anti-Acinetobacter activity comapared to imipenem. The results of this study suggest that essential oils and their individual components can be used as therapeutic substances and as cleaning products since they are effective and eco-friendly. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
18. Impact of morphology of hydrophilic and hydrophobic bentonites on improving the pour point in the recycling of waste cooking oils.
- Author
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Mannu, Alberto, Poddighe, Matteo, Mureddu, Marzia, Castia, Simona, Mulas, Gabriele, Murgia, Fabrizio, Di Pietro, Maria Enrica, Mele, Andrea, and Garroni, Sebastiano
- Subjects
- *
EDIBLE fats & oils , *PETROLEUM waste , *MANUFACTURING processes , *FREE fatty acids , *VEGETABLE oils - Abstract
Waste Cooking Oils (WCOs) are generated worldwide through industrial food processing and household use, posing environmental concerns upon disposal. Bentonites often showed to be effective in removing minor contaminants in vegetable oil refining. The present research focused on the processing of raw WCOs using four bentonites, two commercials and two obtained by ball milling of the latest. The different bentonites (hydrophobic and hydrophilic) were characterized before and after ball milling (BM) procedure, including an exhaustive analyses of crystal structure, morphology and surface area via x-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and N 2 -physisorption technique. Optimization of BM processing in terms of milling time was achieved within 60 min. The milled powders were then tested as adsorbents for recycling WCOs with different degrees of decomposition (expressed in terms of free fatty acids, FFAs, content). Employing a design of experiments approach, the impact of five parameters (FFAs content, temperature, specific surface area, stirring, BM time) on the resulting pour point (PP), taken as a quality benchmark for recycled oil, was assessed. Quantitative multivariate statistical analysis revealed temperature's negligible role and identified the significant impact of two characteristics of the bentonite (specific superficial area and ball milling time), as well as the relevant role of the stirring during the treatment. At the end, hydrophilic bentonite resulted able to improve the PP of waste oils with a low content of free fatty acids of about 10 °C. [Display omitted] • Hydrophobicity of bentonites is a pivotal parameter in waste cooking oil recycling • It is possible to improve the recycling outcome of waste cooking oil with bentonite by ball milling pre-treatment • Refining of waste cooking oils with bentonite is not temperature-depending • Pour point of recycled vegetable oils can be consistently improved by choosing the proper bentonite and condition [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Distributed measurement of supercontinuum generation along a silica fiber taper using a confocal spectrometer
- Author
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Haddad Yosri, Sylvestre Thibaut, Beugnot Jean-Charles, Margueron Samuel, and Fanjoux Gil
- Subjects
fiber optics ,nonlinear optics ,supercontinuum generation ,rayleigh scattering ,scanning microscopy ,distributed measurements ,Applied optics. Photonics ,TA1501-1820 ,Optics. Light ,QC350-467 - Abstract
A highly sensitive distributed measurement technique is employed to map supercontinuum generation along a tapered silica optical fiber. This technique, which utilizes a confocal Raman micro-spectrometer, relies on analyzing far-field frequency-resolved Rayleigh scattering along the waveguide with micrometer-scale spatial resolution and high spectral resolution. Non-destructive and non-invasive, the mapping system enables observation of every stage of supercontinuum generation along the fiber cone, including cascade Raman scattering, four-wave mixing, and dispersive wave generation. Consequently, it unveils unique nonlinear spatial dynamics that are beyond the reach of standard spectral analyzers.
- Published
- 2024
- Full Text
- View/download PDF
20. THE POLLEN MORPHOLOGY OF DIFFERENT IRIS L. SPECIES FROM ROMANIA.
- Author
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GEORGESCU, Mihaela Ioana and DOBRIN, Aurora
- Subjects
POLLEN ,PALYNOLOGY ,MORPHOLOGY ,SPECIES ,POLLEN dispersal ,VETERINARY medicine ,BOTANICAL gardens - Abstract
In order to have proper identification of Iris species, many scientific works are referring to the morphological features of pollen grains as adequate sources of information about the origin and variability concerning the different populations of Iris. According to several taxonomic works, in Romania are 17 (18) species of Iris. There is a lack of information about the morphology of pollen in Iris species from our country. SEM analyses of pollen from five populations of Iris species from the Botanical Garden of the University of Agronomic Science and Veterinary Medicine of Bucharest revealed that four of them had reticulated exine, respectively Iris germanica, I. pseudacorus, I. variegate, and I. suaveolens and one had gemmated exine - Iris pumila. The pollen morphological description presented in this study may be of systematic significance to Iris species, enabling species distinction. [ABSTRACT FROM AUTHOR]
- Published
- 2023
21. The Application of Physicochemical Methods to Studying the Processes of Remineralization of Hard Dental Tissues in Dentistry.
- Author
-
Kasatkin, V. E., Adzhieva, A. K., Kasatkina, I. V., and Zalavutdinov, R. Kh.
- Subjects
- *
SCANNING probe microscopy , *DENTAL pulp , *OPTICAL spectroscopy , *DENTISTRY , *BLEACHING (Chemistry) , *IMPEDANCE spectroscopy - Abstract
The process of remineralization of hard dental tissues using electrophoresis with a BV preparation that provides the formation of a precipitate of calcium phosphate (brushite) upon the interaction of its components is studied by physicochemical methods including electrochemical impedance spectroscopy and optical and scanning probe microscopy with microanalysis. It is shown in the in vitro experiments that the electrical resistance of a tooth can serve as a criterion of the efficiency of blocking of the dentin canaliculi by the formed precipitate of brushite. The depth of the zone of remineralization is assessed in the case of the treatment with a BV preparation by the method of applications and using electrophoresis. It is found that the latter method possesses a higher efficiency with respect to both the degree of blocking of the canaliculi and depth of penetration into the hard dental tissues. A method of therapy of teeth with the vital pulp is developed based on these studies that shows a high efficiency in the patients from the control group. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
22. Sub-micrometer Focusing and High-Resolution Imaging with Refractive Lenses and Multilayer Laue Optics
- Author
-
Bajt, Saša, Schroer, Christian G., Jaeschke, Eberhard J., editor, Khan, Shaukat, editor, Schneider, Jochen R., editor, and Hastings, Jerome B., editor
- Published
- 2020
- Full Text
- View/download PDF
23. Electronic Processes at the Carbon-Covered (100) Collector Tungsten Surface.
- Author
-
Gotsis, Harilaos J., Bacalis, Naoum C., and Xanthakis, John P.
- Subjects
TUNNEL diodes ,FIELD emission ,TUNGSTEN ,ELECTRIC fields ,POTENTIAL energy - Abstract
We have performed density functional VASP calculations of a pure and of a carbon-covered (100) tungsten surface under the presence of an electric field E directed away from the surface. Our aim is to answer the question of an increased penetrability of electrons at the collector side of a nanometric tunnel diode when covered by carbon atoms, a purely quantum mechanical effect related to the value of the workfunction Φ. To obtain Φ at a non-zero electric field we have extrapolated back to the electrical surface the straight line representing the linear increase in the potential energy with distance outside the metal-vacuum interface. We have found that under the presence of E the workfunction Φ = E
vac − EF of the (100) pure tungsten surface has a minor dependence on E. However, the carbon-covered tungsten (100) surface workfunction Φ(C − W) has a stronger E dependence. Φ(C − W) decreases continuously with the electric field. This decrease is ΔΦ = 0.08 eV when E = 1 V/nm. This ΔΦ is explained by our calculated changes with electric field of the electronic density of both pure and carbon-covered tungsten. The observed phenomena may be relevant to other surfaces of carbon-covered tungsten and may explain the reported collector dependence of current in Scanning Field Emission Microscopy. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
24. Microbial biofilm root canals and new approaches to the diagnosis and treatment of the chronic forms of pulpitis using a photoactivatable disinfection and ultrasonic treatment
- Subjects
хронический пульпит ,корневые каналы ,микробная биопленка ,эндодонтическое лечение ,ультразвуковая ирригация ,фотодинамическая терапия ,антимикробная активность in vitro ,chronic pulpitis ,root canals ,microbial biofilm ,endodontic treatment is ultrasonic irrigation ,photodynamic therapy ,scanning microscopy ,antimicrobial activity in vivo ,Dentistry ,RK1-715 - Abstract
Clinical and laboratory study and evaluation of the effectiveness of ultrasonic treatment of the root canal system in combination with photodynamic therapy, in relation to the microflora of root canals in vitro and in the process of complex treatment of patients with inflammatory diseases of dental pulp. In the control subgroups, we conducted instrumental and medicamental processing of root canals. In the comparison group were given the combined treatment with ultrasonic activation of irrigant and further photodynamic treatment. Evaluate the influence of ultrasonic treatment in combination with photoactivatable system disinfection was performed according to the frequency of the diagnosed complications in the treatment of various forms of chronic pulpitis. The structure of the biofilm root canals was studied using scanning electron microscopy (SEM) using a microscope Quantum 3D (USA). Statistical processing of data in 5 replicates and were processed by parametric statistics for small samples by Manna-Whitney test (p < 0,05). When performing scanning electron microscopy revealed the existence of high level of microbial contamination of areas of the root canal and dentinal tubules. In subgroups, where it was used the standard method of treatment, the percentage of re-treatment and surgical intervention prevails compared to the study group. According to the results of clinical and microbiological studies have observed a positive trend to reduce the number of the designated pathogens and the use of complex interaction of ULTRASOUND and PDT was the most successful method compared to traditional method of treatment
- Published
- 2020
25. The influence of modern endodontic technologies on processing of root canals in the treatment of apical periodontitis
- Subjects
хронический апикальный периодонтит ,корневые каналы ,микробная биопленка ,эндодонтические технологии ,ультразвуковая ирригация ,система самоадаптирующихся файлов ,сканирующая микроскопия ,chronic apical periodontitis ,root canals ,microbial biofilm ,endodontic technologies ,ultrasonic irrigation ,a self-adapting system files ,scanning microscopy ,Dentistry ,RK1-715 - Abstract
The aim of this study was to conduct clinical and laboratory studies in the process of complex treatment of patients with chronic apical periodontitis and assessing the effectiveness of endodontic technologies of root channels with the use of self-adapting the SAF files, ultrasonic treatment, 3% solution of sodium hypochlorite and 2% chlorhexidine solution. In the process, were selected 77 patients with a diagnosis of chronic apical periodontitis. Then there were formed 3 groups and 6 subgroups. In the control subgroups, we conducted instrumental and medicamental processing of root canals with manual instruments using a 3% solution of sodium hypochlorite and 2% chlorhexidine solution. In the comparison group were given the combined treatment with ultrasonic activation of irrigants (3% sodium hypochlorite, 2% chlorhexidine solution.) and the SAF system with the same irrigation solutions, respectively. Clinical impact evaluation method dresses: women's treatment on the outcome of endodontic treatment was performed according to the frequency of the diagnosed complications a year after treatment of apical periodontitis. The structure of the biofilm root canals was studied using scanning electron microscopy (SEM) using a microscope Quantum 3D (USA).According to the results of clinical and microbiological studies have observed a positive trend to reduce the number of the designated pathogens when irrigation SAF, as in the application solution of 3% sodium hypochlorite and 2% chlorhexidine solution.
- Published
- 2020
26. High-Energy Transformations of Fossil Fuels in the Cement Industry
- Author
-
Mirosław Szwed, Witold Żukowski, Krzysztof Misztal, and Rafał Kozłowski
- Subjects
toxicity ,air pollution ,greenhouse gases ,scanning microscopy ,Technology - Abstract
The energy stored in fossil fuels is released through combustion and is a fundamental process in the production of cement. The negative aspect of this combustion is the emission of greenhouse gases and dust. This paper presents the results of a study conducted within a cement plant in Ożarów (south-eastern Poland). The chemical properties (selected elements) in the needles of Scots pine (Pinus sylvestris L.) were determined. The needle surface was scanned using a scanning electron microscope (SEM) and was characterised in terms of chemical composition through energy dispersive spectroscopy (EDS). The concentrations of selected analytes in the biennial needles formed the following descending sequence: Fe > Al > Mn > Zn > Cu > Pb > Cr > Ni. SEM/EDS microphotographs showed the presence of particles of varying shape, size and chemical composition indicative of anthropogenic origin.
- Published
- 2023
- Full Text
- View/download PDF
27. Imaging vibrations of electromechanical few layer graphene resonators with a moving vacuum enclosure.
- Author
-
Lu, Heng, Yang, Chen, Tian, Ye, Lu, Jun, Xu, Fanqi, Zhang, Ce, Chen, FengNan, Ying, Yan, Schädler, Kevin G., Wang, Chinhua, Koppens, Frank H.L., Reserbat-Plantey, Antoine, and Moser, Joel
- Subjects
- *
RADIO lines , *RESONATORS , *OPTICAL measurements , *MODE shapes , *VIBRATIONAL spectra , *NANOELECTROMECHANICAL systems - Abstract
Imaging the vibrations of nanomechanical resonators means measuring their flexural mode shapes from the dependence of their frequency response on in-plane position. Applied to two-dimensional resonators, this technique provides a wealth of information on the mechanical properties of atomically-thin membranes. We present a simple and robust system to image the vibrations of few layer graphene (FLG) resonators at room temperature and in vacuum with an in-plane displacement precision of ≈0.20 μ m. It consists of a sturdy vacuum enclosure mounted on a three-axis micropositioning stage and designed for free space optical measurements of vibrations. The system is equipped with ultraflexible radio frequency transmission lines to electrically actuate resonators. With it we characterize the lowest frequency mode of FLG resonators by measuring its frequency response as a function of position on the membrane and by extracting its effective mass. We use the background noise of the undriven vibrational spectrum to calibrate in-plane displacement. Finally, we measure the first three vibration modes of a resonator whose membrane is partially folded and find that folds locally suppress vibrations. • Flexural vibrations of few layer graphene resonators are imaged by moving a large vacuum enclosure. • The effective mass of the fundamental mode is measured. • Background noise of the undriven vibrational spectrum is used to calibrate in-plane displacement. • Ultraflexible transmission lines are developed to drive resonators at radio frequencies. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
28. Continuous scanning mode for ptychography
- Author
-
Robinson, Ian [Research Complex at Harwell, Didcot, Oxfordshire (United Kingdom)]
- Published
- 2014
- Full Text
- View/download PDF
29. Polarimetric optical scanning microscopy of zebrafish embryonic development using the coherency matrix.
- Author
-
Le Gratiet, Aymeric, Bendandi, Artemi, Sheppard, Colin J. R., and Diaspro, Alberto
- Abstract
Many of the most important resolution improvements in optical microscopy techniques are based on the reduction of scattering effects. The main benefit of polarimetry‐based imaging to this end is the discrimination between scattering phenomena originating from complex systems and the experimental noise. The determination of the coherency matrix elements from the experimental Mueller matrix can take advantage of scattering measurements to obtain additional information on the structural organization of a sample. We analyze the contrast mechanisms extracted from (a) the coherency matrix elements, (b) its eigenvalues and (c) the indices of polarimetric purity at different stages of zebrafish embryos, based on previous work using Mueller matrix optical scanning microscopy. We show that the use of the coherency matrix and related decompositions leads to an improvement in the imaging contrast, without requiring any complicated algebraic operations or any a priori knowledge of the sample, in contrast to standard polarimetric methods. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
30. The Use of Atomic Force Microscopy in Comprehensive Assessment of the "Mother—Placenta—Fetus" System in Obstetric and Endocrine Pathology during Pregnancy.
- Author
-
Pavlova, T. V., Shchegolev, A. I., Kaplin, A. N., Malyutina, E. S., Selivanova, A. V., and Zemlyanskaya, L. O.
- Subjects
- *
ATOMIC force microscopy , *ENDOCRINE system , *PLACENTA , *FETAL ultrasonic imaging , *FETUS , *UMBILICAL cord , *ULTRACOLD molecules , *BLOOD circulation disorders - Abstract
Atomic force microscopy is not very popular in practical health care, therefore, its potential is not studied enough, for example, in obstetrics when studying the "mother—placenta—fetus" system. Our study summarizes the possibilities of using atomic force microscopy for detection of various circulatory disorders and vascular changes at the microscopic level in the uterus (endometrium and myometrium), placenta, and umbilical cord in the main variants of obstetric and endocrine pathology. For instance, in the case of endocrine pathologies, changes in the form of stasis, sludge, diapedesis, ischemia, destruction and separation of endotheliocytes in villous blood vessels were found in the mother. The oxygen content in erythrocytes also naturally decreased in pathologies; poikilo- and anisocytosis were observed. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
31. The Structure and Porosity of Plasma Coatings.
- Author
-
Sokolov, V. N., Chernov, M. S., Kalita, V. I., Komlev, D. I., and Radyuk, A. A.
- Abstract
Porous coatings are actively used in engineering practice. The porous coating determines the reliability of the operation of the intraosseous implant and the heat transfer process when the aggregate state of the refrigerant is changed. The choice of method for quantitative analysis of porosity is determined by the structure of the coating. In this study, plasma coatings sprayed from powders were analyzed. A porosity of 10.3% inside the alumina coating was analyzed by mercury porosimetry. The main volume of the porosity of the coating is formed by pores ranging in size from 0.13 to 0.36 μm; their share in the total volume is 68.29%. The remaining volume is distributed in sizes of 0.04–0.12 mm, 0.58–4.66 mm, and 5.66–18.2 mm. Microtomography makes it possible to get a more complete general idea of the macro- and microstructure of coatings, establishing the mechanisms of its formation, and to obtain data on the real shape of the pores. A quantitative description of the visible pores of three-dimensional capillary-porous 3CaO⋅Al
2 O3 coatings in the form of ridges and depressions was determined by raster image analysis using special STIMAN programs. The porosity of this coating is 39.7% of the distribution over four pore groups: 0.74–3.56, 4.34–11.57, 14.08–55.65, 67.73–267.71 mm. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
32. Electronic Processes at the Carbon-Covered (100) Collector Tungsten Surface
- Author
-
Harilaos J. Gotsis, Naoum C. Bacalis, and John P. Xanthakis
- Subjects
carbon-covered tungsten surface ,workfunction ,VASP calculation ,scanning microscopy ,tunnel diode ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
We have performed density functional VASP calculations of a pure and of a carbon-covered (100) tungsten surface under the presence of an electric field E directed away from the surface. Our aim is to answer the question of an increased penetrability of electrons at the collector side of a nanometric tunnel diode when covered by carbon atoms, a purely quantum mechanical effect related to the value of the workfunction Φ. To obtain Φ at a non-zero electric field we have extrapolated back to the electrical surface the straight line representing the linear increase in the potential energy with distance outside the metal-vacuum interface. We have found that under the presence of E the workfunction Φ = Evac − EF of the (100) pure tungsten surface has a minor dependence on E. However, the carbon-covered tungsten (100) surface workfunction Φ(C − W) has a stronger E dependence. Φ(C − W) decreases continuously with the electric field. This decrease is ΔΦ = 0.08 eV when E = 1 V/nm. This ΔΦ is explained by our calculated changes with electric field of the electronic density of both pure and carbon-covered tungsten. The observed phenomena may be relevant to other surfaces of carbon-covered tungsten and may explain the reported collector dependence of current in Scanning Field Emission Microscopy.
- Published
- 2022
- Full Text
- View/download PDF
33. Scanning Plasmon-Enhanced Microscopy for Simultaneous Optoelectrical Characterization.
- Author
-
Symonowicz J, Jan A, Yan H, Chhowalla M, and Di Martino G
- Abstract
Scanning microscopy methods are crucial for the advancement of nanoelectronics. However, the vertical nanoprobes in such techniques suffer limitations such as the fragility at the tip-sample interface, complex instrumentation, and the lack of in operando functionality in several cases. Here, we introduce scanning plasmon-enhanced microscopy (SPEM) and demonstrate its capabilities on MoS
2 and WSe2 nanosheets. SPEM combines a nanoparticle-on-mirror (NPoM) configuration with a portable conductive cantilever, enabling simultaneous optical and electrical characterization. This distinguishes it from other current techniques that cannot provide both characterizations simultaneously. It offers a competitive optical resolution of 600 nm with local enhancement of optical signal up to 20,000 times. A single gold nanoparticle with a 15 nm radius forms pristine, nondamaging van der Waals contact, which allows observation of unexpected p-type behavior of MoS2 at the nanoscale. SPEM reconstructs the NPoM method by eliminating the need for extensive statistical analysis and offering excellent nanoscale mapping resolution of any selected region. It surpasses other scanning techniques in combining precise optical and electrical characterization, interactive simplicity, tip durability, and reproducibility, positioning it as the optimal tool for advancing nanoelectronics.- Published
- 2024
- Full Text
- View/download PDF
34. Fiber-based combined optical coherence and multiphoton endomicroscopy
- Author
-
Liu, Gangjun and Chen, Zhongping
- Subjects
Engineering ,Atomic ,Molecular and Optical Physics ,Physical Sciences ,Animals ,Fluorescent Dyes ,Fourier Analysis ,Heart ,Lasers ,Microscopy ,Fluorescence ,Multiphoton ,Optical Devices ,Optical Fibers ,Optical Phenomena ,Rabbits ,Tomography ,Optical Coherence ,optical coherence microscopy ,multiphoton microscopy ,multimodal imaging ,scanning microscopy ,fiber device ,Optical Physics ,Biomedical Engineering ,Opthalmology and Optometry ,Optics ,Ophthalmology and optometry ,Biomedical engineering ,Atomic ,molecular and optical physics - Abstract
A fiber-based multimodal imaging system that combines multiphoton microscopy (MPM) with Fourier domain optical coherence microscopy (OCM) is reported. The system uses a fiber-based femtosecond laser, a fiber coupler, and a double-clad fiber (DCF) device. The fiber laser has a central wavelength of 1.04 μm and bandwidth of 29 nm. Longer excitation wavelength is used to increase penetration depth and increase the excitation efficiency for dyes, such as red fluorescent dyes. A single mode fiber coupler is used to replace the free-space beam splitter and one arm of the coupler is fused with a double-clad fiber device. The MPM and OCM share the same excitation light path in the core of a double-clad fiber, while the OCM and MPM signals were collected by the core and clad of the double-clad fiber, respectively. The performance of the introduced double-clad device is analyzed. The device can confine all the excitation light in the core and has a collection efficiency of 20% for the MPM signal. The efficiency can be further increased by fusing more multimode fibers with the DCF. Simultaneous optical coherence microscopic imaging, second harmonic generation imaging, and two-photon excitation fluorescence imaging are demonstrated in biological samples.
- Published
- 2011
35. Basic Techniques in Fluorescence and Electron Microscopy
- Author
-
Kuroiwa, Haruko, Kuroiwa, Tsuneyoshi, editor, Miyagishima, Shinya, editor, Matsunaga, Sachihiro, editor, Sato, Naoki, editor, Nozaki, Hisayoshi, editor, Tanaka, Kan, editor, and Misumi, Osami, editor
- Published
- 2017
- Full Text
- View/download PDF
36. Corrosion damage of 316L steel surface examined using statistical methods and artificial neural network.
- Author
-
Kubisztal, Julian, Kubisztal, Marian, and Haneczok, Grzegorz
- Subjects
- *
ARTIFICIAL neural networks , *STEEL , *ALGORITHMS - Abstract
Detailed examination of corrosion‐induced changes of the 316L steel surface (immersed in 5 wt% NaCl solution) is presented and discussed. The evolution of the stable pit depth (hav) with the immersion time (t) was established using 3D maps and statistic techniques. It was found that hav∝tn with n ≈ 0.5. Moreover, determination of the pit area allows estimating the curve current density (j) versus the immersion time and it was found that j∝t−m with m ≈ 1. A novel technique for surface corrosion degree determination is based on analysis of 2D grayscale images instead of black and white images showing that corrosion morphology was elaborated. For this purpose a three‐layered, feed‐forward neural network with the Levenberg–Marquardt backpropagation training algorithm was used. It was shown that a dependence corrosion degree versus immersion time (S‐type curve) can be fully described by the proposed procedure. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
37. Development of a high‐precision XYZ translator and estimation of beam profile of the vacuum ultraviolet and soft X‐ray undulator beamline BL‐13B at the Photon Factory.
- Author
-
Aiura, Yoshihiro, Ozawa, Kenichi, Mase, Kazuhiko, Minohara, Makoto, and Suzuki, Satoshi
- Abstract
A high‐precision XYZ translator was developed for the microanalysis of electronic structures and chemical compositions on material surfaces by electron spectroscopy techniques, such as photoelectron spectroscopy and absorption spectroscopy, utilizing the vacuum ultraviolet and soft X‐ray synchrotron radiation at an undulator beamline BL‐13B at the Photon Factory. Using the high‐precision translator, the profile and size of the undulator beam were estimated. They were found to strongly depend on the photon energy but were less affected by the polarization direction. To demonstrate the microscopic measurement capability of an experimental apparatus incorporating a high‐precision XYZ translator, the homogeneities of an SnO film and a naturally grown anatase TiO2 single crystal were investigated using X‐ray absorption and photoemission spectroscopies. The upgraded system can be used for elemental analyses and electronic structure studies at a spatial resolution in the order of the beam size. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
38. Three new records of Anthocerotophyta for Western Africa (Sierra Leone) based on spore ornamentation of a specimen collected by A. Harrington, with an emphasis on Anthoceros sect. Fusiformes Grolle.
- Author
-
Sérgio, Cecília, Draper, David, and Porley, Ronald D.
- Subjects
- *
SPORES , *SCANNING electron microscopy , *SECTS - Abstract
Introduction. During an investigation into the world-wide distribution of Anthoceros caucasicus Steph., we examined a voucher collected from Sierra Leone by A. J. Harrington in 1966 and subsequently studied by E. W. Jones. Methods. Based on spore observations using light and scanning electron microscopy we found that three Anthocerotophyta taxa were present in this mixed collection. Key results. We report Anthoceros aff. bharadwajii Udar & A.K.Asthana new to Africa, Phaeoceros laevis (L.) Prosk. new to Sierra Leone and tropical Africa, and Anthoceros punctatus L. new to Sierra Leone and western mainland Africa. Conclusions.Anthoceros caucasicus should be removed from the Sierra Leone bryoflora list, and possibly from tropical Africa. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
39. Real‐time video mosaicking to guide handheld in vivo microscopy.
- Author
-
Yin, Chengbo, Wei, Linpeng, Kose, Kivanc, Glaser, Adam K., Peterson, Gary, Rajadhyaksha, Milind, and Liu, Jonathan T. C.
- Abstract
Handheld and endoscopic optical‐sectioning microscopes are being developed for noninvasive screening and intraoperative consultation. Imaging a large extent of tissue is often desired, but miniature in vivo microscopes tend to suffer from limited fields of view. To extend the imaging field during clinical use, we have developed a real‐time video mosaicking method, which allows users to efficiently survey larger areas of tissue. Here, we modified a previous post‐processing mosaicking method so that real‐time mosaicking is possible at >30 frames/second when using a device that outputs images that are 400 × 400 pixels in size. Unlike other real‐time mosaicking methods, our strategy can accommodate image rotations and deformations that often occur during clinical use of a handheld microscope. We perform a feasibility study to demonstrate that the use of real‐time mosaicking is necessary to enable efficient sampling of a desired imaging field when using a handheld dual‐axis confocal microscope. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
40. LamNI – an instrument for X‐ray scanning microscopy in laminography geometry.
- Author
-
Holler, Mirko, Odstrčil, Michal, Guizar-Sicairos, Manuel, Lebugle, Maxime, Frommherz, Ulrich, Lachat, Thierry, Bunk, Oliver, Raabe, Joerg, and Aeppli, Gabriel
- Subjects
- *
COMPUTED tomography , *THREE-dimensional imaging , *TOMOGRAPHY , *HARD X-rays , *MICROSCOPY - Abstract
Across all branches of science, medicine and engineering, high‐resolution microscopy is required to understand functionality. Although optical methods have been developed to 'defeat' the diffraction limit and produce 3D images, and electrons have proven ever more useful in creating pictures of small objects or thin sections, so far there is no substitute for X‐ray microscopy in providing multiscale 3D images of objects with a single instrument and minimal labeling and preparation. A powerful technique proven to continuously access length scales from 10 nm to 10 µm is ptychographic X‐ray computed tomography, which, on account of the orthogonality of the tomographic rotation axis to the illuminating beam, still has the limitation of necessitating pillar‐shaped samples of small (ca 10 µm) diameter. Large‐area planar samples are common in science and engineering, and it is therefore highly desirable to create an X‐ray microscope that can examine such samples without the extraction of pillars. Computed laminography, where the axis of rotation is not perpendicular to the illumination direction, solves this problem. This entailed the development of a new instrument, LamNI, dedicated to high‐resolution 3D scanning X‐ray microscopy via hard X‐ray ptychographic laminography. Scanning precision is achieved by a dedicated interferometry scheme and the instrument covers a scan range of 12 mm × 12 mm with a position stability of 2 nm and positioning errors below 5 nm. A new feature of LamNI is a pair of counter‐rotating stages carrying the sample and interferometric mirrors, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
41. Histology and ultramorphology of the mesenteric sacs in the Neotropical termite Neocapritermes opacus (Blattaria, Termitidae, Termitinae).
- Author
-
da Silva, Iago Bueno, Buganeme, Sandra Daruiche, and Costa-Leonardo, Ana Maria
- Subjects
COCKROACHES ,TERMITES ,HISTOLOGY ,MICROSCOPICAL technique ,MUSCLES - Abstract
Neocapritermes opacus is a Neotropical termite, which feeds on a variety of food sources, including highly decayed wood and humus. Similar to many Termitidae, this species contains a mixed segment in the intestine, an anatomic distinct region composed of both mesenteric and proctodeal tissues. In Neocapritermes spp., a pair of intestinal protrusions referred to as mesenteric sacs are associated with the mixed segment. In the present study, with the aid of histological and scanning microscopy techniques, we provide a detailed anatomical and histological analyses of the mesenteric sacs in N. opacus workers. The results showed that the paired sacs are contiguous with the mesenteric component of the mixed segment and open into the ectoperitrophic space. The wall of the sacs is an epithelium composed of two types of cells (regenerative and principal) and musculature. The regenerative cells are located at the epithelium base and organized in regenerative crypts, while the principal cells are columnar and enfold the lumen of the sacs. Brush border was observed in the principal cell apex, aligned closely to rod-like bacteria. Secretory activity was observed in the principal cells and vesicles cast from them toward the sacs lumen, probably result of an apocrine activity. The sac epithelium was of mesenteric affiliation but differed from the intestinal midgut. The proctodeal epithelium was markedly different. Although some studies have been interpreted the mesenteric sacs as Malpighian nodules or Malpighian sacs, our results support that these structures are morphologically distinct and that the occurrence of mesenteric sacs is a synapomorphy for Neocapritermes. The precise function of the mesenteric sacs in termite digestion remains unclear; therefore, further investigations should carefully consider their secretory activity and symbiont population, aiming to understand their development and maintenance among these Neotropical species. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
42. Effect of sonic and mechanical toothbrushes on subgingival microbial flora: A comparative in vivo scanning electron microscopy study of 8 subjects.
- Author
-
Williams, Karen B., Cobb, Charles M., Taylor, Heidi J., Brown, Alan R., and Bray, Kimberly Krust
- Subjects
TOOTHBRUSHES ,SONICATION ,MICROORGANISMS ,GINGIVA ,SCANNING electron microscopy ,SPIROCHETES ,PERIODONTITIS ,PERIODONTAL pockets ,DENTAL plaque - Abstract
Objectives: The purpose of this initial study was to evaluate the effects of both a sonic and a mechanical toothbrush versus the effects of no treatment on depth of subgingival penetration of epithelial and tooth-associated bacteria. Methods and materials: Eight adult subjects exhibiting advanced chronic periodontitis with at least 3 single-rooted teeth that were in separate sextants with facial pockets ≥ 4 mm and ≤ 8 mm and that required extraction constituted the experimental sample. Teeth were either subjected to 15 seconds of brushing with a mechanical toothbrush or a sonic toothbrush or left untreated. The test tooth and the associated soft tissue wall of the periodontal pocket were removed as a single unit. Samples were processed and coded for blind examination by scanning electron microscopy. Distributional and morphologic characteristics of dominant bacteria with specific emphasis on spirochetes were evaluated for both epithelial- and tooth-associated plaque. Results: No differences were found in morphotypes or distributional and aggregational characteristics of epithelial-associated microbes in the 1- to 3-mm subgingival zone between the mechanical and sonic toothbrush-treated groups and the control group. Both toothbrush groups featured disruption of microbes that extended up to 1 mm subgingivally. Root surfaces on the sonic-treated samples appeared plaque-free at low magnification; however, at 4,700× a thin lair of mixed morphotypes and intact spirochetes was found supragingivally and slightly subgingivally. In comparison, mechanical brush samples featured incompletely removed plaque, both supragingivally and subgingivally, with intact spirochetes present on subgingival root surfaces. Conclusion: Results suggest similar effects for both sonic and mechanical toothbrushes on epithelial- and tooth-associated bacterial plaque in periodontal pockets and adjacent root surfaces that extend up to 1 mm subgingivally. Further, the presence of intact subgingival spirochetes suggests limited exposure to acoustical or mechanical energy from the toothbrushes evaluated. (Quintessence Int 2001; 32: 147-154) [ABSTRACT FROM AUTHOR]
- Published
- 2001
43. Resolution and contrast enhancement of laser-scanning multiphoton microscopy using thulium-doped upconversion nanoparticles.
- Author
-
Kostyuk, Alexey B., Vorotnov, Artem D., Ivanov, Andrey V., Volovetskiy, Arthur B., Kruglov, Aleksandr V., Sencha, Lyudmila M., Liang, Liuen, Guryev, Evgenii L., Vodeneev, Vladimir A., Deyev, Sergey M., Lu, Yiqing, and Zvyagin, Andrei V.
- Abstract
High-contrast optical imaging is achievable using phosphorescent labels to suppress the short-lived background due to the optical backscatter and autofluorescence. However, the long-lived phosphorescence is generally incompatible with high-speed laser-scanning imaging modalities. Here, we show that upconversion nanoparticles of structure NaYF
4 :Yb co-doped with 8% Tm (8T-UCNP) in combination with a commercial laser-scanning multiphoton microscopy are uniquely suited for labeling biological systems to acquire high-resolution images with the enhanced contrast. In comparison with many phosphorescent labels, the 8T-UCNP emission lifetime of ∼ 15 µs affords rapid image acquisition. The high-order optical nonlinearity of the 8T-UCNP (n ≈ 4, as confirmed experimentally and theoretically) afforded pushing the resolution limit attainable with UCNPs to the diffraction-limit. The contrast enhancement was achieved by suppressing the background using (i) bandpass spectral filtering of the narrow emission peak of 8T-UCNP at 455-nm, and (ii) time-gating implemented with a time-correlated single-photon counting system that demonstrated the contrast enhancement of > 2.5-fold of polyethyleneimine-coated 8T-UCNPs taken up by human breast adenocarcinoma cells SK-BR-3. As a result, discrete 8T-UCNP nanoparticles became clearly observable in the freshly excised spleen tissue of laboratory mice 15-min post intravenous injection of an 8T-UCNP solution. The demonstrated approach paves the way for high-contrast, high-resolution, and high-speed multiphoton microscopy in challenging environments of intense autofluorescence, exogenous staining, and turbidity, as typically occur in intravital imaging. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
44. Electrochemical Diagnostics of Sprayed Fiber-Reinforced Concrete Corrosion.
- Author
-
Raczkiewicz, Wioletta and Kossakowski, Paweł Grzegorz
- Subjects
SHOTCRETE ,CONCRETE corrosion ,FIBER-reinforced concrete ,REINFORCED concrete corrosion ,REINFORCED concrete ,REINFORCING bars - Abstract
Sprayed fiber-reinforced concrete is used in construction for the execution and repair of reinforced concrete elements. It is believed that the addition of steel fibers is most effective, due to their parameters and low costs. Some researchers, however, suggest that the addition of steel fibers can contribute to the initiation of corrosion of the main reinforcement. In consideration of the differences of opinion on the corrosion resistance of sprayed fiber-reinforced concrete, it has become necessary to analyze this issue. The article presents comparative studies of corrosion assessments of the main reinforcement in specimens made of ordinary concrete and concrete with steel fibers. The tests were performed using a semi non-destructive galvanostatic pulse method, which allows location of the areas of corrosion and estimation of the reinforcement corrosion activity. In order to initiate the corrosion processes the specimens were subjected to freezing cycles in NaCl solution. In addition, the shrinkage and compressive strength of specimens were measured, and the observation of specimen structure under a scanning microscope was performed. It was found that galvanostatic pulse method allowed estimation of the reinforcement corrosion progress. The corrosion of the main reinforcement in steel fiber reinforced concrete specimens was less advanced than in the specimens without fibers. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
45. Optical vortex trajectory as a merit function for spatial light modulator correction.
- Author
-
Szatkowski, Mateusz, Popiołek Masajada, Agnieszka, and Masajada, Jan
- Subjects
- *
INSPECTION & review , *OPTICAL vortices , *LASER beams , *SPATIAL light modulators - Abstract
Highlights • Most of the correction methods use visual inspection as a beam quality merit function. • Visual beam inspection is not sufficient when precise SLM application is needed. • Two quality criteria, based on more objective methods are proposed. • Detection of small deviation from ideal beam is possible. • Both can be applied in any system, where the beam intensity is recorded. Abstract Spatial light modulator (SLM) is a modern device extensively used for laser beam shaping. Over the years, its quality has been significantly improved. Nevertheless, there is still a need to correct its imperfections. In this paper we propose two criteria which allow to examine correction effectiveness of SLM. One is based on the Laguerre–Gauss transform and the second uses optical vortex dynamics which exposes a high sensitivity to any beam imperfections. It is based on the vortex internal scanning method, where the shape of vortex trajectory provides information about SLM correction quality. In this paper we test its sensitivity to astigmatism, which was introduced manually by SLM, after proper correction. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
46. Antifungal efficiency of wild plants against human-opportunistic pathogens.
- Author
-
Hashem, M., Alamri, S.A., Shathan, A.A., Alshehri, S.R.Z., Mostafa, Y.S., and El-kott, A.
- Abstract
Fungal infection with opportunistic fungi can cause a serious problem for immunocompromised persons such as organ-transplant recipients, cancer, and HIV/AIDS patients. Control of these organisms using natural products is an interesting strategy to avoid the use of heavy chemotherapy in patients. This study aimed to use the extract of Forsskaolea tenacissima L. and Xanthium spinosum L. to suppress the growth of Candida albicans and Geotrichum candidum and to investigate their potential mode of action. Different plant extracts were tested for their antifungal activity using disc diffusion method and their mode of action was explored using the scanning electron microscopy (SEM) and gas chromatography-mass spectrometry (GC-MS). The results showed that chloroform extract of X. spinosum was the most effective against G. candidum, inhibiting its growth at very low concentration (38 μg/mL). Chloroform extract of F. tenacissima was the most effective against C. albicans, with a minimum inhibitory concentration of 39 μg/mL. SEM demonstrated the fungitoxicity of the plant extracts against both pathogens. C. albicans treated with plant extract were invaginated and ruptured and the treated mycelia of G. candidum were distorted and squashed. GC-MS analysis showed that the chloroform extract of both plants had 13 different compounds. Due to these promising results, these extracts should be further investigated and tested on different strains of C. albicans and G. candidum towards validation of their efficacy as a natural drug. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
47. Label-free in vivo pathology of human epithelia with a high-speed handheld dual-axis confocal microscope.
- Author
-
Chengbo Yin, Linpeng Wei, Abeytunge, Sanjee, Peterson, Gary, Rajadhyaksha, Milind, and Liu, Jonathan T. C.
- Subjects
- *
ORAL mucosa , *MICROSCOPES , *EARLY diagnosis , *EPITHELIUM , *SKIN imaging , *PATHOLOGY - Abstract
There would be clinical value in a miniature optical-sectioning microscope to enable in vivo interrogation of tissues as a real-time and noninvasive alternative to gold-standard histopathology for early disease detection and surgical guidance. To address this need, a reflectancebased handheld line-scanned dual-axis confocal microscope was developed and fully packaged for label-free imaging of human skin and oral mucosa. This device can collect images at >15 frames/s with an optical-sectioning thickness and lateral resolution of 1.7 and 1.1 µm, respectively. Incorporation of a sterile lens cap design enables pressure-sensitive adjustment of the imaging depth by the user during clinical use. In vivo human images and videos are obtained to demonstrate the capabilities of this high-speed optical-sectioning microscopy device. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
48. The Nanodiffraction beamline ID01/ESRF: a microscope for imaging strain and structure.
- Author
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Leake, Steven J., Chahine, Gilbert A., Djazouli, Hamid, Zhou, Tao, Richter, Carsten, Hilhorst, Jan, Petit, Lucien, Richard, Marie-Ingrid, Morawe, Christian, Barrett, Raymond, Zhang, Lin, Homs-Regojo, Roberto A., Favre-Nicolin, Vincent, Boesecke, Peter, and Schülli, Tobias U.
- Subjects
- *
MONOCHROMATORS , *MICROSCOPES - Abstract
The ID01 beamline has been built to combine Bragg diffraction with imaging techniques to produce a strain and mosaicity microscope for materials in their native or operando state. A scanning probe with nano‐focused beams, objective‐lens‐based full‐field microscopy and coherent diffraction imaging provide a suite of tools which deliver micrometre to few nanometre spatial resolution combined with 10−5 strain and 10−3 tilt sensitivity. A detailed description of the beamline from source to sample is provided and serves as a reference for the user community. The anticipated impact of the impending upgrade to the ESRF – Extremely Brilliant Source is also discussed. The ID01 beamline has been built to combine Bragg diffraction with imaging techniques to produce a strain and mosaicity microscope for materials in their native or operando state. A detailed description of the beamline from source to sample is provided and serves as a reference for the user community. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
49. Analysis of the Structure and Composition of Fe2O3 Oxides Subjected to Magnetic Pulse Treatment.
- Author
-
Virus, A. A., Shipko, M. N., Stepovich, M. A., Kaminskaya, T. P., Korovushkin, V. V., Tikhonov, A. I., and Savchenko, E. S.
- Abstract
The structure and composition of iron ore (hematite) powders before and after treatment with weak pulsed magnetic fields are studied with scanning electron microscopy, scanning probe microscopy, X‑ray microanalysis, and Mössbauer spectroscopy. Hematite samples, which are structure-forming elements during the preparation of hexagonal barium and strontium ferrites after their grinding in an attritor, are objects of the research. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
50. THE SYNTHESIS OF COMPOSITES BASED ON POWDERS OF ALUMINIUM WITH SMALL ADDITIONS OF BARIUM
- Author
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S.A. Bibanaeva, V.M. Skachkov, B.N. Latosh, and N.A. Sabirzyanov
- Subjects
aluminium powder ,barium ,cermet ,specific surface ,microhardness ,scanning microscopy ,Physical and theoretical chemistry ,QD450-801 - Abstract
The article describes a method of producing a porous material of aluminum powders doped with small additions of barium after treatment with water. Studies of the strength properties, microstructure, specific surface area of the original samples and derived products were performed.
- Published
- 2016
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