Bidirectional diffraction and re-initiation of irregular structure detonation

K-Ta mixed oxides photocatalysts have been prepared by impregnation followed by calcination. The influence of the reaction temperature (450°C–900°C) on the phase formation, crystal morphology, and photocatalytic activity in hydrogen generation of the produced materials was investigated. The detailed analysis has revealed that all products exhibit high crystallinity and irregular structure. Moreover, two different crystal structures of potassium tantalates such as KTaO3and K2Ta4O11were obtained. It was also found that the sample composed of KTaO3and traces of unreacted Ta2O5(annealed at 600°C) exhibits the highest activity in the reaction of photocatalytic hydrogen generation. The crystallographic phases, optical and vibronic properties were examined by X-ray diffraction (XRD) and diffuse reflectance (DR) UV-vis and resonance Raman spectroscopic methods, respectively. Morphology and chemical composition of the produced samples were studied using a high-resolution transmission electron microscope (HR-TEM) and an energy dispersive X-ray spectrometer (EDX) as its mode.

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The method for detection repetitive elements in textures with irregular structure

WSCG 2018 - Short papers proceedings ◽

10.24132/csrn.2018.2802.1 ◽

2018 ◽

Author(s):

Vasyl Tereshchenko ◽

Yaroslav Tereshchenko

Keyword(s):

Repetitive Elements ◽

Irregular Structure

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The Effect of Polymerization Temperature on the Properties of Polyvinyl Fluoride Polymerization in Supercritical Carbon Dioxide

Journal of Physics Conference Series ◽

10.1088/1742-6596/2101/1/012063 ◽

2021 ◽

Vol 2101 (1) ◽

pp. 012063

Author(s):

Wei Liu ◽

Yanzhong Zhang ◽

Huaiyun Chang ◽

Rong Cai ◽

Peiliang Ma

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

Reaction Medium ◽

Chemical Processes ◽

Light Transmittance ◽

Polymerization Temperature ◽

Irregular Structure ◽

Lower Melting Point ◽

Application Fields ◽

Supercritical Carbon

Abstract The ongoing search for environmentally friendlier alternative to the organic solvents used in chemical processes has led to the development of technologies based on supercritical carbon dioxide (scCO2), which is non-flammable, non-toxic and relatively inert fluid. Polymer chemistry does not escape this trend. Fluoropolymers prepared in scCO2 have many special properties, which are different from fluoropolymers that use water as the reaction medium, this paper studies the effect of polymerization temperature on polyvinyl fluoride polymerization in supercritical carbon dioxide. The results show that as the polymerization temperature increases, the intrinsic viscosity and shear viscosity of the polymer gradually decreases; at the same time, the increasing of polymerization temperature leads to higher proportion of irregular structure of the polymer, which causes lower melting point and lower crystallinity, and the film prepared by the resin also exhibits a higher visible light transmittance. The above results show that the resin polymerized in supercritical carbon dioxide can impart better performance to conventional polymerization, which expands the potential application fields of the resin.

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Metal-insulator transition in an irregular structure of coupled metallic chains

Synthetic Metals ◽

10.1016/0379-6779(94)90181-3 ◽

1994 ◽

Vol 65 (2-3) ◽

pp. 195-201 ◽

Cited By ~ 2

Author(s):

V.N. Prigodin ◽

K.B. Efetov

Keyword(s):

Insulator Transition ◽

Metal Insulator Transition ◽

Metal Insulator ◽

Irregular Structure

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Biochars Originating from Different Biomass and Pyrolysis Process Reveal to Have Different Microbial Characterization: Implications for Practice

Sustainability ◽

10.3390/su12041526 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1526

Author(s):

Wioletta Żukiewicz-Sobczak ◽

Agnieszka Latawiec ◽

Paweł Sobczak ◽

Bernardo Strassburg ◽

Dorota Plewik ◽

...

Keyword(s):

Waste Management ◽

Microscopic Analysis ◽

Regular Structure ◽

Plate Count ◽

Botanical Origin ◽

Sustainable Technologies ◽

Plate Count Agar ◽

Irregular Structure ◽

Wide Range ◽

Production Areas

Sustainable technologies are increasingly promoted in various production areas. Protection of natural resources, as well as rational waste management, may lead to better optimization of technologies. Biochar, a product of pyrolysis of organic residues has found wide applications in waste management, agriculture, energy and construction industry. In the present study biochar samples produced in Poland and in Brazil were analysed for microbial content using three substrates: Plate Count Agar, Malt Agar, and Potato Agar. Both qualitative and quantitative measurements were done. Microscopic analysis of the biochar structure was also performed. We found that microbial cultures in both biochars represented a wide range of biodiversity of microorganisms genera and species. We demonstrate that the biochar samples differ depending on the botanical origin as well as on the production technology. Structure of the tested samples also varied depending on the botanical origin. Sample 1-PL (pine) was characterised by a compact and regular structure, while sample 2-PL (oak) showed porous and irregular structure. Sample from Brazil (1-BR) showed a more delicate structure than Polish biochars. Obtained properties may suggest a range of implications for practice.

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Compositional and micromorphological features of hypoplastic enamel in children’s permanent teeth

BIO Web of Conferences ◽

10.1051/bioconf/20202202013 ◽

2020 ◽

Vol 22 ◽

pp. 02013

Author(s):

Natalya Ozhgikhina ◽

Daria Kiseleva ◽

Evgeny Shagalov ◽

Evgenia Bimbas ◽

Natalya Myagkova

Keyword(s):

Protein Structures ◽

Clinical Manifestations ◽

Local Environment ◽

Comparative Investigation ◽

Permanent Teeth ◽

Common Disease ◽

Enamel Hypoplasia ◽

Globular Structure ◽

Prismatic Structure ◽

Irregular Structure

Enamel hypoplasia is the most common disease of hard tooth tissues of non-carious origin emerging before their eruption. It develops as a result of a delayed and perverse function of ameloblasts leading to the violation of the processes of formation and mineralization of tooth protein structures. The clinical manifestations of enamel hypoplasia are spots, defects in the form of pits, cup-shaped depressions, grooves on various surfaces of child’s teeth. The work is devoted to a comparative investigation of microstructural and compositional features of intact and hypoplastic enamel in children’s permanent teeth using analytical scanning electron microscopy with energy-dispersive X-ray spectroscopy. The hypoplastic enamel is enriched in organic substance and has an irregular structure without keyhole-shaped prismatic structure. Mineral deposition is indicated for hypoplastic enamel including hydroxyapatite with globular structure and calcite and halite, which might have been caused by the violation of extracellular local environment probably due to the enamel hypoplasia development.

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Effects of Laser Doping on the Formation of the Selective Emitter of a c-Si Solar Cell

Applied Sciences ◽

10.3390/app10134554 ◽

2020 ◽

Vol 10 (13) ◽

pp. 4554

Author(s):

Jeong Eun Park ◽

Won Seok Choi ◽

Jae Joon Jang ◽

Eun Ji Bae ◽

Donggun Lim

Keyword(s):

Laser Fluence ◽

Contact Resistivity ◽

Process Conditions ◽

Laser Doping ◽

Selective Emitter ◽

Melting Phenomenon ◽

Irregular Structure ◽

Si Solar Cell ◽

Additional Processing ◽

By Products

Laser doping, though able to improve cell characteristics, enables the formation of a selective emitter without the need for additional processing. Its parameters should be investigated to minimize laser defects, such as the heat-affected zone (HAZ), and to obtain a low contact resistance. Herein, the laser fluence and speed were changed to optimize process conditions. Under a laser fluence of 1.77 J/cm2 or more, the surface deteriorated due to the formation of the HAZ during the formation of the laser doping selective emitter (LDSE). The HAZ prevented the formation of the LDSE and impaired cell characteristics. Therefore, the laser speeds were changed from 10 to 70 mm/s. The lowest contact resistivity of 1.8 mΩ·cm2 was obtained under a laser fluence and speed of 1.29 J/cm2 and 10 mm/s, respectively. However, the surface had an irregular structure due to the melting phenomenon, and many by-products were formed. This may have degraded the efficiency due to the increased contact reflectivity. Thus, we obtained the lowest contact resistivity of 3.42 mΩ·cm2, and the damage was minimized under the laser fluence and speed of 1.29 J/cm2 and 40 mm/s, respectively.

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