Thermo gravimetric study of coal in the presence of polymers showed that availability of high asphalt-resinous components -asphaltenes and resins benzene within the temperature of 360 -443 0 С in the content was reduced. The optimum catalytics of coal hydrogenation is the compositions on the basis of Pd / C, at which there was the greatest absorption of hydrogen and Co / C, where the hydrogenation rate was maximum.
In this work, a method of obtaining graphene layers from natural source specifically from rice husk was developed. A rice husk (RH) was used as a raw material, and potassium hydroxide was used as activation agent. The graphene layers were obtained after four successive stages: pre-carbonization, desilication in 1 M NaOH solution, chemical activation and exfoliation of the carbonized rice husk. The obtained samples were studied using Raman spectroscopy, TEM and SEM; the Raman peaks evidenced the presence of graphene multilayers in the sample. A detailed observation of Raman spectroscopy showed that the obtained samples with ratio of 1/4 and 1/5 (RH/KOH) consisted of graphene layers with a high content of amorphous component. The yield of the product was ~ 3% by weight. This study can provide a new way to the large-scale synthesis of low-cost single and multi-layered graphene using rice husk or other renewable resources. Университет Неаполя Федерико II, Неаполь, Италия *E-mail: makpal_90.90@mail.ru В данной работе разработан метод получения слоев графена из природного ресурса. В качестве исходного материала использована рисовая шелуха (РШ), а в качестве активирующего реагента использован гидроксид калия. Слои графена были получены последовательными стадиями: предварительная карбонизация, десиликация в 1 М растворе NaOH, химическая активация и эксфолиация карбонизированной рисовой шелухи. Полученные образцы исследованы с использованием Рамановской спектроскопии, просвечивающей и сканирующей электронной микроскопии. Рамановские пики подтвердили наличие графеновых многослойных слоев в образце. Подробное наблюдение с использованием Рамановской спектроскопии показало, что полученные образцы соотношением 1/4 и 1/5 (РШ/KOH) состоят из графеновых слоев с высоким содержанием аморфного компонента. Выход продукта составлял ~ 3 мас.%. Это исследование может обеспечить новый способ крупномасштабного синтеза однослойного и многослойного графена с использованием рисовой шелухи или других возобновляемых ресурсов. Неаполь Федерико II Университеті, Неаполь, Италия *E-mail: makpal_90.90@mail.ru Бұл жұмыста табиғи ресурстан графен қабаттарын алу әдісі жасалған. Бастапқы материал ретінде күріш қауызы, ал активтендіруші реагент ретінде калий гидроксиді қолданылған. Графен қабаттары сатылы стадиямен алынған: алдын-ала карбонизациялау, карбонизделген күріш қауызын 1 М NaOH ерітіндісінде десиликациялау, химиялық активациялау және эксфоляциялау. Алынған үлгілер Раман спектроскопия, трансмиссия және сканирлеуші электрондық микроскопия қолданып зерттелінді. Раман спектрлері үлгінің құрамында көп қабатты графеннің бар екенін растады. Раман спектроскопиямен терең зерттеу нәтижесінде, 1/4 және 1/5 (КҚ/KOH) қатынасында алынған үлгілер графен қабаттарынан және аморфты көмірден тұратыны анықталды. Өнімнің жалпы шығымы ~ 3 мас.%. Бұл зерттеу жұмысы күріш қауызынан немесе басқа да жаңартылымды ресурстардан бір қабатты және көп қабатты графенді ауқымды синтездеудің жаңа әдісін қамтуы мүмкін. KeywordsТүйін сөздер: графен; күріш қауызы; карбонизация; э...
Mechanical recovery of oil by oil sorbents is one of the most important countermeasures in marine oilspill response. The preparation of oil-sorbents from agricultural waste increases economic return and reduces pollution. The sorption capacities of the carbonized rice husks and the apricot stone compared in relation to different petroleum products. Sorption capacity showed strong dependence on the particle size of sorbent and oil film thickness. The phase composition, microstructure and morphology of the composite material C/SiO 2 , prepared by carbonize o f rice husks were investigated by X-ray diffraction analysis, FTIR spectrometry and scanning election microscope (SEM).
<p>In the paper microscopic structure and physicochemical characteristics of asphaltenes were investigated. Asphaltene was precipitated from natural bitumen of oil sand of Munaily-Mola deposit using organic solvent of petroleum ether. According to results of our work, we found that the largest yield of asphaltens was reached by using the petroleum ether in 40-fold amount in relation to the initial hitch of bitumen. Chemical composition of precipitated asphaltenes aggregates were studied on FT-Infra red spectrometer Spectrum-65 at 450-4000 cm<sup>-1</sup>. At the Infrared spectrum, that the broad absorption band of asphaltenes at 3000-3600 cm-1 are characterizing the presence of polycyclic aromatic hydrocarbons and aliphatic chains in the samples of asphaltens. Elemental composition of the samples of asphaltenes on the installation of X-ray fluorescent spectrometer "Focus-M2". Also found the presence of two crystalline phases. One - quartz content is less than one percent. Another phase is also present in very small quantities and is represented by a single line of diffraction d = 4.158 Å. The microstructures and microanalysis of asphaltenes were investigated with an scanning electron microscopy (Quanta 3D 200i) at an accelerated voltage of 20 kV and a pressure of 0.003 Pa at National Nanotechnological Laboratory of Open Type of Kazakh National University. Microscopic images showed that the asphaltenes have a medium-ordered structure, the main component of the surface is<br /> represented by amorphous carbon.</p>
Biomass-based carbon nanofibers (CNF) were synthesized using lignin extracted from sawdust and polyacrylonitrile (PAN) (30:70) with the help of the electrospinning method and subsequent stabilization at 220 °C and carbonization at 800, 900, and 1000 °C. The synthesized CNFs were studied by scanning electron microscopy, energy-dispersive X-ray analysis, Raman spectroscopy, and the Brunauer–Emmett–Teller method. The temperature effect shows that CNF carbonized at 800 °C has excellent stability at different current densities and high capacitance. CNF 800 in the first test cycle at a current density of 100 mA/g shows an initial capacity of 798 mAh/g and an initial coulomb efficiency of 69.5%. The CNF 900 and 1000 show an initial capacity of 668 mAh/g and 594 mAh/g, and an initial Coulomb efficiency of 52% and 51%. With a long cycle (for 500 cycles), all three samples at a current density of 500 mA/g show stable cycling in different capacities (CNF 800 in the region of 300–400 mAh/g, CNF 900 and 1000 in the region of 100–200 mAh/g).
A novel approach for depositing of hydroxyapatite (HA) films on titanium substrates by using high energy ball milling (HEBM) has been developed. It was demonstrated that a heat treatment of the mechanically coated HA at 800 °C for one hour leads to partial transformation of HA phase to -TCP. It appears that the grain boundary and interface defects formed during MCS reduce this characteristic transformation temperature. Also, it was shown that Ti incorporation into the HA structure causes the lattice shrinkage and reduction of its grain size as compared to pure HA, but also promote the phase transformation of HA to TCP at high temperature. It is important that doping HA by silicon, while also significantly decrease crystallinity of deposited HA layer, results in hindering of the phase transformation process. The Si-doped HA does not show phase transition or decomposition after heat treatment even at<br />900 °C. The samples were investigated by X-ray diffraction, scanning electron microscope, Energy dispersive spectroscopy, Atomic force microscopy, Transmission electron microscopy, inductively coupled plasma (ICP) optical emission spectrometer, Vickers microhardness, Electron paramagnetic resonance.
One of the priority trends of carbon nanotechnology is creation of nanocomposite systems. Such carbon nanostructured composites were produced using - raw materials based on the products of agricultural waste, such as grape stones, apricot stones, rice husk. These products have a - wide spectrum of application and can be obtained in large quantities. The Institute of Combustion Problems has carried out the work on synthesis of the nanostructured carbon sorbents for multiple applications including the field of biomedicine. The article presents the data on the synthesis and physico-chemical properties of carbonaceous sorbents using physicochemical methods of investigation: separation and purification of biomolecules; isolation of phytohormone - fusicoccin; adsorbent INGO-1 in the form of an adsorption column for blood detoxification, oral (entero) sorbent - INGO-2; the study of efferent and probiotic properties and sorption activity in regard to the lipopolysaccharide (LPS), new biocomposites - based on carbonized rice husk (CRH) and cellular microorganisms; the use of CRH in wound treatment. A new material for blood detoxication (INGO-1) has been obtained. Adsorption of p-cresyl sulfate and indoxyl sulfate has shown that active carbon adsorbent can remove clinically significant level of p-cresyl sulfate and indoxyl sulfate from human plasma. Enterosorbent INGO-2 possesses high adsorption activity in relation to Gram-negative bacteria and their endotoxins. INGO-2 slows down the growth of conditionally pathogenic microorganisms, without having a negative effect on bifido and lactobacteria. The use of enterosorbent INGO-2 for sorption therapy may provide a solution to a complex problem - detoxication of the digestive tract and normalization of the intestinal micro ecology. The immobilized probiotic called "Riso-lact" was registered at the Ministry of Health of the Republic<br />of Kazakhstan as a biologically active food additive. The developed technology is patented and provides production of the medicine in the form of freeze-dried biomass immobilized in vials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.