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The production of sewage sludge has been sharply increasing by municipal sludge treatment plants in China. Sewage sludge is a difficult waste to manage not only due to the high quantities produced but also due to its high concentration of heavy metals and pathogens. The pyrolytic conversion of sewage sludge to biochar and then applied to the land is a sustainable management potion. Therefore, the aim of this work is to evaluate the characteristics of nutrients and heavy metals in biochar from sewage sludge pyrolysis, and pot experiments were carried out with different treatments consisting of infertile and contaminated soils. The results showed that the content of major plant nutrients (N, P, K) in sewage sludge biochar meets agricultural requirements. The concentrations of heavy metals (Cu, Pb, Zn, Cd, and Cr) were evidently increased in biochar, but those of available heavy metals were decreased. The sewage sludge biochar can improve soil fertility and enhance plant growth while not increasing plant uptake of heavy metals, and remedied contaminated soil by reducing the plant availability of heavy metals.
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Analysis of sawmill waste charring process in the steel retorts. There is described the process of sawmill waste charring in the steel retorts that belong to the contractor operating in Forest Inspectorate Kozienice. The process consists of nine stages and lasts over 76 hours, including 14 h (19%) of the effective charring, 47 h (62%) of cooling the retorts, and the remaining 15 h for cleaning, loading and unloading of the retort. The economic analysis for the assumed data showed that average specific cost of obtaining a 2.5-kg bag of charcoal made of sawmill waste was equal to about 5 PLN, while the limit profitability point, calculated for the process with the use of a new retort, amounted to 87 bags of charcoal, and with the depreciated retort – 67 bags.
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Wood and other biomass have the great potential of decreasing carbon dioxide emissions to the atmosphere, or at least mitigating the speed of the increase in the concentration of carbon dioxide. This paper presents an analysis of the possible use of degraded land – thermal power plant ash ponds – for the growth of fast-growing trees for fuel wood and the subsequent utilization of this fuel wood by means ofa verified technique – co-combustion with coal, or a proposed technique – pyrolysis. Pyrolysis of wood with the combustion of pyrolysis gases and carbon sequestration would provide approximately 26% more favorable effects on climate change than the co-combustion of wood in a coal-fired boiler.
Acetylcholine (ACh), a well known animal neurotransmitter was isolated from tissues of Pharbitis nil using five different methods. Its presence in plant extract was confirmed by infrared spectroscopy and mass spectrometry. For quantitative estimation of ACh in P. nil seedlings pyrolysis-gas chromatography was applied. The presence of ACh was found in all organs of the examined plant: seeds, shoot apex, cotyledons, leaves, shoots and roots. However, the highest level of the investigated substance was noted in the youngest growing parts. In 5-day-old etiolated seedlings they were cotyledons, whereas in 14 day-old green plants - shoot apex and young leaves.
The synergistic effect of ammonium polyphosphate (APP) and boric acid (BA) on the flame retardancy and thermal degradation of pine needles was investigated. Thermogravimetric analysis (TGA) showed that the presence of an ammoniumpolyphosphate and boric acid system increased the char residue and decreased the pyrolysis temperature of the pine needles. The derivative thermogravimetric analysis (DTG) showed that the ammonium polyphosphate and boric acid had shifted the degradation peaks of the pine needles to lower temperatures. The cone calorimetry test results showed that the values of HRR, THR, SPR, TSP and the mass loss (%) of the pine needles treated with ammonium polyphosphate and boric acid (APP/BA = 3/2)were significantly lower than the other samples. Therefore, the APP and BA system had a better effect on the pine needles overall than the APP alone.
The aim of the study was to analyze the kinetic parameters (activation energy Ea, pre-exponential coefficient A, rate constant k) of thermolysis in torrefied and raw willow wood (Salix viminalis L.), as well as to determine the effect of thermal modification conditions on the kinetics of this process. Samples of raw and torrefied willow wood in a steam atmosphere were analysed. The samples were subjected to thermogravimetric analysis under isothermal conditions. Analyses were conducted in an atmosphere of helium at 270–330°C. TG and DTG curves were recorded. The thermal characteristics of the samples were based on thermogravimetric analysis under dynamic conditions at a temperature of up to 600°C. On the basis of the data obtained from the TGA analyses, the kinetic parameters were calculated and statistical and mathematical analyses of the results were performed.
W artykule zamieszczono informacje dotyczące kierunku rozwoju źródeł biopaliw pochodzenia roślinnego. Jednym z potencjalnych źródeł najbliższej przyszłości mogą być mikroalgi. Omówiono proces konwersji biomasy mikroalg, w tym proces pirolizy obejmujący pozyskanie ciekłego biopaliwa zwanego bio-olejem oraz możliwości praktycznego zastosowania.
Malignant melanoma (melanoma malignum) is one of the most dangerous types of tumor. It is very difficult to cure. In recent years, a lot of attention has been given to chemoprevention. This method uses natural and synthetic compounds to interfere with and inhibit the process of carcinogenesis. In this study, a new treatment strategy was proposed consisting of a combination of 5,7-dimethoxycoumarin (DMC), an activator of melanogenesis, and valproic acid (VPA), a well-known drug that is one of the histone deacetylase inhibitors (HDACis). In conjunction with 1 mM VPA, all of the tested concentrations of DMC (10–150 μM) significantly decreased the proliferation of A-375 cells. VPA and DMC also induced the synthesis of melanin and the formation of dendrite and star-shaped cells. Tyrosinase gene expression and tyrosinase activity significantly increased in response to VPA treatment. Pyrolysis with gas chromatography and mass spectrometry (Py-GC/MS) was used to investigate the structure of the isolated melanin. This showed that the quantitative and qualitative components of melanin degradation products are dependent on the type of applied melanogenesis inductor. Products derived from eumelanin were detected in the pyrolytic profile of melanin isolated from A-375 cells stimulated with DMC. Thermal degradation of melanin isolated from melanoma cells after exposure to VPA or a mixture of VPA and DMC revealed the additional presence of products derived from pheomelanin.
Chemical and elemental composition of selected lignocellulose materials was determined and next the materials were used to produce a series of active carbons for electrochemical hydrogen adsorption under strictly repeatable conditions. Chemical activation (900oC) with the application of KOH (4:1) was used for the development of the porous structure. Prior to activation all materials were pyrolysed at 700oC applying a slight temperature increase rate (3oC/min). Produced active carbons had diverse parameters of the porous structure and considerable BET surface areas ranging from 2178 to 2815 m2/g. Experiments showed feasibility of electrosorption of hydrogen on the surface of active carbons produced from commonly available, cheap and frequently waste lignocellulose materials. The type of the applied precursor has a significant effect on the development of the porous structure and hydrogen sorption. The highest hydrogen sorption value of Hc=1.91% weight and Hc=1.90% weight were obtained on AC from cherry stone shells and from oak wood.
Chemical composition of lignocellulose materials and porous structure of activated carbons. Chemical and elemental compositions of selected lignocellulose materials were determined and next a series of activated carbons was produced from these materials under strictly repeatable conditions. The chemical activation method (900oC) using KOH (4:1) was applied for the development of the porous structure. Prior to activation all raw materials were subjected to pyrolysis at 700oC using a slight temperature increase rate (3oC/min). Produced activated carbons had varied porous structure parameters and considerable BET surface areas ranging from 2026 to 2884 m2/g. It was shown that the type of the applied precursor has a significant effect on the development of the porous structure.
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