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1.
Molecules ; 27(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36364016

RESUMO

Biochar from forest biomass and its remains has become an essential material for environmental engineering, and is used in the environment to restore or improve soil function and its fertility, where it changes the chemical, physical and biological processes. The article presents the research results on the opportunity to use the pyrolysis process to receive multifunctional biochar materials from oak biomass. It was found that biochars obtained from oak biomass at 450 and 500 °C for 10 min were rich in macronutrients. The greatest variety of the examined elements was characterized by oak-leaf pyrolysate, and high levels of Ca, Fe, K, Mg, P, S, Na were noticed. Pyrolysates from acorns were high in Fe, K, P and S. Oak bark biochars were rich in Ca, Fe, S and contained nitrogen. In addition, biomass pyrolysis has been found to improve energy parameters and does not increase the dust explosion hazard class. The oak biomass pyrolytic at 450 and 500 °C after 10 min increases its caloric content for all samples tested by at least 50%. The highest caloric value among the raw biomass tested was observed in oak bark: 19.93 MJ kg-1 and oak branches: 19.23 MJ kg-1. The mean and highest recorded Kstmax were 94.75 and 94.85 bar s-1, respectively. It can be concluded that pyrolysis has the potential to add value to regionally available oak biomass. The results described in this work provide a basis for subsequent, detailed research to obtain desired knowledge about the selection of the composition, purpose, and safety rules of production, storage, transport and use of biochar materials.


Assuntos
Quercus , Madeira , Biomassa , Madeira/química , Casca de Planta , Carvão Vegetal/química , Solo/química , Folhas de Planta
2.
Molecules ; 27(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36144557

RESUMO

The purpose of this paper is to review the scientific results and summarise the emerging topic of the effects of statistic magnetic field on the structure, biochemical activity, and gene expression of plants. The literature on the subject reports a wide range of possibilities regarding the use of the magnetic field to modify the properties of plant cells. MFs have a significant impact on the photosynthesis efficiency of the biomass and vigour accumulation indexes. Treating plants with SMFs accelerates the formation and accumulation of reactive oxygen species. At the same time, the influence of MFs causes the high activity of antioxidant enzymes, which reduces oxidative stress. SMFs have a strong influence on the shape of the cell and the structure of the cell membrane, thus increasing their permeability and influencing the various activities of the metabolic pathways. The use of magnetic treatments on plants causes a higher content of proteins, carbohydrates, soluble and reducing sugars, and in some cases, lipids and fatty acid composition and influences the uptake of macro- and microelements and different levels of gene expression. In this study, the effect of MFs was considered as a combination of MF intensity and time exposure, for different varieties and plant species. The following article shows the wide-ranging possibilities of applying magnetic fields to the dynamics of changes in the life processes and structures of plants. Thus far, the magnetic field is not widely used in agricultural practice. The current knowledge about the influence of MFs on plant cells is still insufficient. It is, therefore, necessary to carry out detailed research for a more in-depth understanding of the possibilities of modifying the properties of plant cells and achieving the desired effects by means of a magnetic field.


Assuntos
Antioxidantes , Campos Magnéticos , Antioxidantes/metabolismo , Carboidratos , Ácidos Graxos/metabolismo , Expressão Gênica , Lipídeos , Plantas/genética , Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Açúcares/metabolismo
3.
Molecules ; 25(15)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752237

RESUMO

This article presents the findings of a study investigating the explosion and combustion parameters of dust from the raw biomass of wheat straw and energy willow and from the products of biomass torrefaction generated at temperatures ranging from 220 to 300 °C. Agricultural waste and energy crops and their modifications, e.g., in the torrefaction process, did not find a place in explosive risk research, which the authors decided to present in their work. The study was designed to estimate explosion hazard during the processing of the materials into fuels and during the storage process. The measurements recorded a maximum explosion pressure Pmax in the case of dust from biomass ranging from 7.2 to 7.3 bar and for dust from torrefied materials amounting to 7.5-9.2 bar, and a maximum rate of pressure rise over time (dp/dt)max in raw biomass ranging from 201.4 to 261.3 bar/s and in torrefied materials amounting to 209.6-296.6 bar/s. The estimated explosion index Kstmax for raw biomass was 55-72 m*bar/s and for torrefied materials was in the range from 57 to 81 m*bar/s. In the results, the authors present values for specific types of fuel which differ significantly depending on the type of biomass. The research findings show that the torrefaction process used in fuel production is not associated with a significantly greater risk of explosion and the materials obtained may safely be used as an alternative to conventional solid fuels. Given the growing interest in the use of biomass and in the variety of biomass processing methods for energy-related purposes, it seems there is a need for research to develop appropriate guidelines and for effective practices to be introduced in the energy industry in order to ensure the safety of the processes used in the production of novel fuels especially in small installations converting these materials into more efficient energy material.


Assuntos
Biomassa , Poeira , Fontes Geradoras de Energia , Explosões , Pirólise , Biotecnologia , Temperatura Alta , Lignina , Pressão , Salix , Triticum
4.
Molecules ; 22(10)2017 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-28972565

RESUMO

This article presents the findings of a study investigating the feasibility of using a magnetic field assisted technique for the water-based extraction of mineral components, polyphenols, and caffeine from dry black and green tea leaves. The authors present a concept of applying constant and variable magnetic fields in the process of producing water-based infusions from selected types of tea. Analyses investigating the effectiveness of the proposed technique in comparison with conventional infusion methods assessed the contents of selected mineral components-i.e., Al, Ca, Cu, K, Mg, P, S, and Zn-which were examined with the use of ICP-OES. The contents of caffeine and polyphenolic compounds were assessed using the HPLC. A changing magnetic field permitted an increased effectiveness of extraction of the mineral components, caffeine, and polyphenols. The findings support the conclusion that a changing magnetic field assisted extraction method is useful for obtaining biologically valuable components from tea infusions.


Assuntos
Extratos Vegetais , Folhas de Planta/química , Chá/química , Cromatografia Líquida de Alta Pressão , Campos Magnéticos , Extratos Vegetais/química , Solubilidade , Espectrometria de Massas em Tandem , Água
5.
Rocz Panstw Zakl Hig ; 68(3): 237-245, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28895389

RESUMO

Background: The processing of tea leaves determines the contents of bioactive ingredients, hence it should be expected that each variety of tea, black, red or green, will represent a different package of compounds of physiological importance. Taste and aroma, as well as price and brand are the main factors impacting consumers' preferences with regard to tea of their choice; on the other hand consumers less frequently pay attention to the chemical composition and nutritional value of tea. Objective: The purpose of the study was assessment of the nutritional value of black, green and white high-quality tea leaf from Chinese plantations based on the chemical composition of the dried leaves as well as minerals and caffeine content in tea infusions. Material and methods: The research material included 18 high-quality loose-leaf teas produced at Chinese plantations, imported to Poland, and purchased in an online store. The analyses included examination of the dried tea leaves for their chemical composition (contents of water, protein, volatile substances and ash) and assessment of selected minerals and caffeine contents in the tea infusions. Results: High-quality Chinese green teas were found with the most valuable composition of minerals, i.e. the highest contents of Zn, Mn, Mg, K, Ca and Al and the highest contents of protein in comparison to the other products. Chinese black teas had the highest contents of total ash and caffeine and white teas were characterized with high content of volatile substances, similar to the black teas, and the highest content of water and the lowest content of total ash. Conclusions: The three types of tea brews examined in the present study, in particular green tea beverages, significantly enhance the organism's mineral balance by providing valuable elements


Assuntos
Antioxidantes/análise , Camellia sinensis/química , Flavonoides/análise , Minerais/análise , Fenóis/análise , Chá/química , Fibras na Dieta/análise , Humanos , Valor Nutritivo , Extratos Vegetais/química , Folhas de Planta/química , Xantinas/análise
6.
Materials (Basel) ; 15(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35806529

RESUMO

Biomass is one of the most important sources of renewable energy. One of the most widely used biomass biofuels is wood pellets. It is an economical, homogeneous and easy-to-use raw material. Biomass is used to generate low-emission energy utilizing the pyrolysis process. Pyrolysis allows for higher energy efficiency with the use of commonly available substrates. This thesis presents the results of research on the possibility of using the pyrolysis process to produce high-energy biocarbons from wood pellets. Data on basic energy parameters and explosivity of biocarbon dust were compiled as criteria for the attractiveness of the solution in terms of energy utility. The research used pellets made of oak, coniferous, and mixed sawdust, which were subjected to a pyrolysis process with varying temperature and time parameters. Carbon, ash, nitrogen, hydrogen, volatile substances, heavy metals, durability and calorific value of the tested materials were carried out. The highest increase in calorific value was determined to be 63% for biocarbons obtained at 500 ℃ and a time of 15 min, compared with the control sample. The highest calorific value among all analyzed materials was obtained from coniferous pellet biocarbon at 31.49 MJ kg-1. Parameters such as maximum explosion pressure, Pmax, maximum pressure increase over time, (dp/dt)max, and explosion rates, Kst max, were also analyzed. It was noted that biomass pyrolysis, which was previously pelletized, improved the energy parameters of the fuel and did not increase the risk class of dust explosion. The lowest and highest recorded values of Kst max for the analyzed materials were 76.53 and 94.75 bar s-1, respectively. The study concluded that the process used for processing solid biofuels did not affect the increase in the danger of dust explosion. The results presented in this article form the basis for further research to obtain detailed knowledge of the safety principles of production, storage, transport and use of these new fuels.

7.
Animals (Basel) ; 12(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36290155

RESUMO

The purpose of the study was to evaluate seasonal changes in selected trace elements such as Fe, Cu, Mn, Zn, and Al in the coat of healthy Hucul horses kept in south-eastern Poland in two different facilities and fed with locally sourced feed. The coat for the study was collected from 24 individuals in autumn, winter, and spring. The concentration of elements in the feed was also determined. The date of collection had a significant effect on the concentration of the micronutrients analysed in the coat of Hucul horses. The highest concentration of Zn was found in the coat taken in summer. The coat taken in autumn had the highest concentrations of Fe, Cu, Mn, and Al compared with the other seasons. The highest concentrations of Fe, Mn, and Al were found in fur taken in winter, with the lowest levels of Zn. Positive correlations were found between the content of iron and manganese, iron and aluminium, and manganese and aluminium in the coat of Hucul horses. A clear inter-individual and inter-stable variability was found, which may indicate the need for further research that also takes into account other factors.

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