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EN
Currently, lithium-ion batteries still use electrodes from graphite, which is a natural resource for non-metallic minerals. As a sustainable plan, research on the manufacture of lithium-ion batteries based on biomass electrodes has prospects for commercial development. In this study, carbon stems of water spinach (Ipomoea Aquatica) were used as electrodes on the battery. Water spinach is processed into nanocarbon by hydrothermal method and pyrolysis. The size of the nanocarbon particles from water spinach in this study was 200 mesh resulting from the grinding method. The type of battery made is a bag battery with a size of 8×12 cm by performing variable optimization by using a concentration of 50% LiCl/Li2SO4 electrolytes media, Polyurethane/Polyacrylate binder, and Triethylamine/Non-emulsifier. The highest power and energy values are generated from carbon based lithium-ion batteries from water spinach with LiCl electrolyte media, Polyurethane binder, and Triethylamine emulsion which is 5.404 W and 4.511 W∙h.
EN
Nowadays, research on the use of pyrolysis products in the broadly understood economy is widely conducted in the world. This publication presents the results of research on the use of biochar primarily as a material for use in agriculture and environmental protection. In particular, its use to improve soil properties and as a component of organic fertilisers or composts, as well as an ingredient for animal bedding in livestock buildings or an additive for silage is discussed. In addition, the possibilities of using biochar in the energy sector as a solid fuel and in the broader field of environmental protection for remediation of contaminated land, for carbon sequestration and as a raw material for the production of activated carbons are discussed.
PL
Przedstawiono zastosowania materiałów mezoporowatych jako adsorbentów w procesie zatężania analitu metodą ekstrakcji w układzie ciecz-ciało stałe. Najczęściej stosowanymi adsorbentami są mezoporowate krzemionki oraz węgle. Modyfikacja powierzchni adsorbentów może przyczynić się do zwiększenia ich selektywności wobec adsorbowanych substancji. Metoda ekstrakcji w układzie ciecz-ciało stałe jest najczęściej stosowana podczas oznaczania substancji metodami chromatograficznymi (HPLC, UPLC, GC).
EN
A review, with 29 refs., of historical and new methods of obtaining mesoporous materials, including their properties and applications. The use of these materials in the detn. of trace amts. of an analyte was discussed. Particular attention was paid to the types and methods of preparing the porous phase for anal. purposes, its properties and the method of sepn. from the analyte (molecular imprinting, magnetic nanoparticles).
4
Content available remote Bonding methods of ceramic materials with deposited carbon layers
EN
In this paper, we present a proposed bonding technology of ceramic materials. It could be applied for manufacturing the excitation source for detection of elements by means of Optical Emission Spectroscopy (OES) method. The biggest challenge was choice of proper bonding technology for materials with screen printed carbon layers as an excitation electrodes. It was caused by a need to avoid a deterioration of electrical properties of the carbon layer during the bonding process. The bonding at low temperature with various glaze layers was verified with addition of noble elements and plasma modification. The results were promising, without any significant destruction of carbon layers.
PL
W tym artykule przedstawiamy proponowaną technologię łączenia materiałów ceramicznych która może być zastosowana przy wytwarzaniu źródła wzbudzenia do detekcji pierwiastków w metodzie optycznej spektroskopii emisyjnej. Wybór odpowiedniej technologii łączenia materiału z warstwami węglowymi wytwarzanymi metodą sitodruku był wyzwaniem z powodu konieczności uniknięcia degradacji właściwości elektrycznych węgla podczas procesu łączenia. Zweryfikowano łączenie w niskiej temperaturze z różnymi warstwami szkliwa z dodatkiem pierwiastków szlachetnych i modyfikacją plazmową. Wyniki były obiecujące, bez znacznego zniszczenia warstw węglowych.
EN
Field measurements of forest biomass are labor-consuming and usually destructive, but such direct datasets are the foundation for further developing indirect estimation such as biomass equation and biomass expansion factors that were used to scale biomass estimation or carbon storage from site or local surveys up to regional or national level. Pinus massoniana is widely distributed throughout 17 provinces of China and has a high economic value. This study is an updated review of the allometric equations, biomass allocation data and productivity estimations in Pinus massoniana forests of China published in articles during the period from 1982 to 2019. Different allometric equations of Pinus massoniana showed site-specific dependences. The aboveground and total tree biomass were expressed as power equations of mean age for Pinus massoniana forests. The mean value of aboveground tree biomass, total tree biomass and ecosystem biomass across all ages for Masson pine forests was 109.81, 127.65 and 138.76 Mg/ha, respectively. The mean proportion of stem, branch and foliage to aboveground tree biomass for Pinus massoniana was 77.1%, 15.9% and 7%, respectively. The tree root biomass continuously increased with the aboveground tree biomass and a power relationship was found between the tree root biomass and aboveground tree biomass for Pinus massoniana forests. The tree net primary productivity increased with aboveground tree biomass for Pinus massoniana forests, and the relationship was expressed as a linear equation. The mean tree, litter and ecosystem net primary productivity was 7.04, 4.88 and 8.30 Mg/ha/year, respectively. These findings provide key parameters for the biomass estimation and carbon accounting studies of widely planted Pinus massoniana forests in China.
PL
Węgiel od lat jest wykorzystywany w polskich domach, lecz wiedza na jego temat nadal jest niewystarczająca. Eksperci Akademii Górniczo-Hutniczej w Krakowie przygotowali zestawienie najważniejszych informacji dotyczących tego surowca, szczególnie przydatnych przy wykorzystaniu go jako głównego źródła ciepła.
EN
Textile wastewater has become one of the serious environmental problems due to containing a high concentration of chemicals with extreme color intensity. Reactive red RB is among the synthetic azo dyes commonly used as a textile colorant with their property are very difficult to degrade naturally. This research was focused on studying the kinetic behavior, and adsorption isotherm of reactive red RB textile dye on coconut leaf stalk activated carbon (CLSC). Coconut leaf stalk carbon was activated using sulphuric acid and sodium hydroxide. It was investigated in terms of chemical functional groups, surface morphology, carbon content, ash content, and adsorption efficiency of reactive red RB textile dye under various conditions of initial pH, incubation time, and dye concentration. The results showed the maximum adsorption efficiency of reactive red RB dye with a concentration dye of 60 mg/l onto CLSC surface activated by sulfuric acid and sodium hydroxide in an experiment carried out at pH 5 for 120 min were 88.73% and 64.27%, respectively. The adsorption isotherm of reactive red RB on the CLSC surface follows the Langmuir isotherm model, which shows that the adsorption process occurs monolayer. In contrast, the adsorption kinetics correspond to pseudo-second-order.
PL
Wiele pierwiastków chemicznych oraz ich związków ma szerokie zastosowanie w produktach dostępnych na rynku. Są obecne zarówno w produktach żywnościowych, preparatach leczniczych, jak i w kosmetykach. Na podstawie przeglądu literatury i danych producenta dokonano analizy ich aktywności oraz potencjalnych korzyści i zagrożeń wynikających z ich stosowania. Przeanalizowano też wpływ tych substancji na środowisko naturalne.
EN
A review, with 35 refs., of chem. elements and their comps. used in foods, drugs and cosmetics. Their activity, potential benefits and risks as well as environmental impacts were taken into consideration.
EN
Anthracosia Shales within the Pennsylvanian-Lower Permian continental succession from the Intra-Sudetic Synclinorium are lacustrine sediments, represented by black shales intercalated with sandstones/mudstones. Mineral composition of each lithology consists of quartz, feldspar, mica, clay minerals (including kaolinite, the content of which decreases upward the section), and carbonates (calcite and siderite). The section is a continuous record of reduction and rise in terrigenous input. Mineral detritus is least weathered in the uppermost part of the Anthracosia Shales. The sedimentation occurred under dysoxic conditions that were ventilated by bottom currents.
EN
This study presents the behavior of a single wall carbon nanotube (SWCNT)/water nanofluid for convective laminar flow inside a straight circular pipe heated by a constant heat flux. Five volume fractions of SWCNT were used to investigate their effect on the heat transfer coefficient, Nusselt number, temperature distribution and velocity field in comparison with pure water flow. One model for each property was tested to calculate the effective thermal conductivity, effective dynamic viscosity, and effective specific heat of the SWCNT/water mixture. The models were extracted from experimental data of a previous work. The outcomes indicate that the rheological behavior of SWCNT introduces a special effect on the SWCNT/water properties, which vary with SWCNT volume fraction. The results show an improvement in the heat transfer coefficient with increasing volume fraction of nanoparticles. The velocity of SWCNT/water nanofluid increased by adding SWCNT nanoparticles, and the maximum increase was registered at 0.05% SWCNT volume fraction. The mixture temperature is increased with the axial distance of the pipe but a reduction in temperature distribution is observed with the increasing SWCNT volume fraction, which reflects the effect of thermophysical properties of the mixture.
EN
The paper is a thermodynamics analysis of the removal of any inert gas from the tank using the vapors of any liquefied petroleum gas cargo (called cargo tank gassing-up operation). For this purpose, a thermodynamic model was created which considers two boundary cases of this process. The first is a ‘piston pushing’ of inert gas using liquefied petroleum gas vapour. The second case is complete mixing of both gases and removal the mixture from the tank to the atmosphere until desired concentration or amount of liquefied petroleum gas cargo in the tank is reached. Calculations make it possible to determine the amount of a gas used to complete the operation and its loss incurred as a result of total mixing of both gases.
EN
In this research, the carbon particle dispersions are made in two different levels as carbon nano tube (CNT) and carbon particle in microns range. The mechanical strength is evaluated for the composites developed by axial loading and bending test analysis. In addition, the air jet abrasive particle erosion study is performed for different angle of impingement. The dispersion of carbon particle in the matrix material has reduced the mechanical strength. The sample with 4% of CNT dispersion in the composite has a maximum strength of 143 MPa and a minimum strength of 112 MPa. For the same combination (4% of CNT composite), the maximum flexural strength is 116 MPa. It is clear to infer that the strength of CNT in matrix materials is superior to the increase in length of carbon particle. The dispersion of carbon particle in the matrix material increases the brittleness and the strength is diminished. During the flexural bending, the fiber delamination occurred with severe deformation in the plain composite. When the materials are subjected to impingement of solid particle, the attrition effect on the exposed surfaces is vulnerable towards erosive mechanism. The presence of carbon in the matrix material has significantly increased the surface property. The results are appreciable for 4% of CNT composite. Especially at 30º, the minimum erosive wear 0.0033 g/g has been recorded. Erosive wear is less at minimum impingement angle and the wear is found increasing at higher impingement angle. Therefore, it is recommended not to add carbon particle to a higher weight percentage, since it leads to brittleness.
PL
Niskotemperaturowe utlenianie wyrobów ogniotrwałych MgO-C jest jednym z czynników wpływających na czas pracy kadzi głównej stalowniczej. Utlenianie ma miejsce podczas eksploatacji urządzenia w temperaturach poniżej 1200 °C w okresach gotowości urządzenia do pracy. W tym czasie utrzymuje się wymaganą temperaturę wyłożenia roboczego, a mieszanina gazów zawierająca tlen, wypełniająca wnętrze kadzi, oddziałuje korozyjnie na część węglową materiałów ogniotrwałych. Badania odwęglania przeprowadzono na formowanych mechanicznie kształtkach z wybranego materiału magnezjowo-węglowego o składzie typowym dla zastosowań w strefach żużla kadzi głównych. Odporność materiału na niskotemperaturowe utlenianie badano w piecu oporowym w zależności od czasu utleniania, temperatury utleniania oraz ciśnienia formowania, od którego zależy porowatość otwarta materiału kształtek. W badaniach użyto dwóch grafitów płatkowych różniących się uziarnieniem i czystością. Badania przeprowadzono według trójpoziomowego planu całkowitego typu 3S, umożliwiającego statystyczną analizę nieliniowej charakterystyki zastępczej odporności materiału na niskotemperaturowe utlenianie. Uzyskane wyniki pozwalają na ocenę wpływu temperatury utleniania, czasu utleniania i porowatości otwartej wykorzystanych materiałów na utlenianie nisko-temperaturowe. Wyniki pracy są praktyczną wskazówką dla użytkowników kadzi głównych.
EN
Low-temperature oxidation of MgO-C refractory materials is one of the factors influencing the length of service of a steel ladle. Oxidation occurs during the ladle’s operation at temperatures below 1200 °C, in the periods when it is kept on standby. At this time, the required temperature of the working lining is maintained, and the mixture of oxygen-containing gases inside the ladle has a corrosive effect on the carbon part of the refractory materials. Investigations of decarburization were conducted on mechanically formed shapes made of a selected magnesia-carbon material with a composition typical for applications in ladle slag zones. The material’s resistance to low-temperature oxidation was tested in resistance furnaces versus time, temperature, and moulding pressure, which determines the open porosity of the shapes’ material. In the investigations, two flake graphites, differing in grain size distribution and cleanness, were used. The tests were carried out according to a three-level full factorial design type 3S, which enables conducting a statistical analysis of the nonlinear substitute characteristics of the material’s resistance to low-temperature oxidation. The obtained results allow evaluating the effect of temperature, time, and open porosity on the process of material’s low-temperature oxidation. The results of work can provide a practical indication for steel ladle users.
EN
The work demonstrates the suppression of the inhibiting effect of the carbon dioxide absorption process by chlorophyll-synthesizing Chlorella microalgae due to sulfur oxide SO2, activators of phosphorus oxide P2O5 and nitrogen oxides NxOy The research presents the experimental dependences of the dynamics of СО2 absorption by microalgae under the critical concentration of inhibitor SO2 in the presence of the P2O5 and NxOy activators. The authors devised the mathematic models of growth of the Chlorella microalgae population depending on the concentration of the phosphorus oxide and nitrogen oxides activators under a permanent concentration of the sulfur oxide inhibitor. The research determined an optimal total concentration of P2O5 activator in the presence of the SO2 inhibitor, as well as an optimal total concentration of the NO2 activator in the presence of the SO2 inhibitor.
EN
The aim of the study was to evaluate the changes in the carbon/nitrogen ratio as a result of different natural methods of sewage sludge treatment from two municipal wastewater treatment plants. The sludge from the first treatment plant was poured into two lagoons, one covered with reed and the other with willow and a field with Californian earthworms. The sludge from the second treatment plant was composted with sawdust. The sludge processed with each method was simultaneously subjected to Effective Microorganisms. The samples of processed sludge from both treatment plants were collected three times. In the first one, after five weeks, four months and ten months from the beginning of treatment. The material from the second treatment plant was composted after four, ten weeks and a year of composting. In the samples taken, the total nitrogen content was determined by means of the Kjeldahl method. The determination of the organic carbon content was carried out on a TOC analyser. The C:N ratio was then calculated. It was found that the changes in the C:N ratio depended on the duration of individual processes, and to a lesser extent on the way they were processed. The carbon content during sludge processing increased or remained at a similar level and the nitrogen content decreased with time of their processing, regardless of the EM addition. The addition of Effective Microorganisms to the sludge treatment reduced the C:N ratio in the first period of time and increased this ratio to the optimal value after 10 months or a year. The best technology for sludge processing appeared to be the technology of heap composting with sawdust and with aeration. The ten-week compost had a suitable C/N ratio for use in lawn production.
18
Content available remote Lightweighting of wishbone finite element analysis
EN
This paper focuses on lightweighting of wishbone structure for ordinary 5-seated commercial vehicle. Typically, the wishbone structure is made of high carbon steel and the aim is to investigate if the composite materials, such as E-Glass/Epoxy, Carbon/Epoxy and Boron/Epoxy, can achieve the lightweighting purpose without compromising material strength. The study is carried out through finite element package (Siemen NX) with the consideration of three different loading conditions, namely, lateral braking force, vertical and longitudinal braking force. Throughout the study, it is found that both Carbon/Epoxy and Boron/Epoxy composites is able to reduce the weight of the component by 46% while maintaining the required strength.
EN
Silicon as a raw material for solar cells can be produced by numerous methods. The carbothermic reduction of silica using electric arc furnace is the most widely used process in silicon industry. This paper presents a new approach to produce solar grade silicon using microwave furnace. Pellets of different sizes were prepared from a mixture of silica and carbon using water and polyvinyl alcohol as binder agents. Raman spectra indicated a peak at about 515 cm−1 attributed to silicon in the pellets prepared with polyvinyl alcohol, and peaks at about 523 cm−1 and 794 cm−1 attributed to silicon and silicon carbide, in the pellets prepared with water. The pellet size affects the absorption of microwave energy emitted from the magnetrons. Polyvinyl alcohol as a binder agent is promising for the production of silicon using microwave furnace.
EN
Gradual increase in the generation of wastewater results from the increasing global population. Thus, new treatment techniques and systems for controlling the treatment process depending on wastewater characteristics are desirable. This paper presents the use of a pilot-scale modified five-stage Bardenpho process with a 10 m3/day capacity for the treatment of real municipal wastewater. The process was developed for this study, and the steady-state removal efficiencies for COD (chemical oxygen demand), TKN (total Kjeldahl nitrogen), NH4+-N (ammonium nitrogen), PO43--P (phosphate phosphoms), SS (suspended solids), and VSS (volatile suspended solids) were 87±5%, 86±12%, 93±14%, 89±9%, 88±8%, 94±4%, and 94±4%, respectively. In the study, the effluent COD, TKN, and TP concentrations were also estimated using a fuzzy logic approach. The results showed that coefficients of determination are higher than 0.80 suggesting that the presented fuzzy logic approach may confidently be used for the estimation of the treatment performance.
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