221 research outputs found
The analysis of mercury content in coals and ashes
It is well known that mercury that enters the atmosphere is a serious threat to the natural environment. From the available literature, it can be stated that fossil fuels are among the main carriers of this fuel. The question arises whether it is the right approach. While the enrichment of bituminous coal produces limited amounts of mercury, they are being released into the atmosphere as a result of the combustion of coal. The situation is similar in the case of biomass, which releases large amounts of mercury into the atmosphere when subjected to the combustion process. While bituminous coal is the carrier of mercury, the application of currently known technology, rational production and the use of fossil fuels make it possible to maximally minimize mercury emissions into the atmosphere. This study evaluated the mercury content in the ashes resulting from the combustion of bituminous coal subjected to the enrichment process. The samples were collected from ten mines located in the Polish part of the Upper Silesian Coal Basin (USCB). In total, thirty coal samples and thirty products of the combustion process were examined. All sixty samples were subjected to physicochemical analysis, including: moisture content, ash content, sulfur content, carbon content, and Gross Calorific Value
The determination of mercury content in the biomass untended for industrial power plant
Biomass is one of the oldest and most widely used renewable
energy sources. The biomass is the whole organic matter of vegetable or
animal origin which is biodegradable. Biomass includes leftovers from
agricultural production, forestry residues, and industrial and municipal
waste. The use of biomass in the power industry has become a standard
and takes place in Poland and other European countries. This paper
discusses the correlation of mercury content in different biomass types
used in the power industry and in products of biomass combustion.
Different biomass types, which are currently burned in a commercial
power plant in Poland, were discussed. A photographic documentation of
different biomass types, such as straw briquettes, wood briquettes, pellets
from energy crops (sunflower husk and wood husk), wood pellets, wood
chips, and agro-biomass (seeds) was carried out. The presented paper
discusses the results obtained for 15 biomass samples. Five selected
biomass samples were burned in controlled conditions in the laboratory at
the University of Silesia. The ash resulting from the combustion of five
biomass samples was tested for mercury content. A total of twenty biomass
samples and its combustion products were tested. Based on the obtained
results, it was found that any supply of biomass, regardless of its type, is
characterized by variable mercury content in dry matter. In the case of e.g.
wood chips, the spread of results reaches 235.1 μm/kg (in dry matter).
Meanwhile, the highest mercury content, 472.4 μm/kg (in dry matter) was
recorded in the biomass of straw, wood pellets, and pellets from energy
crops (sunflower husk). In the case of combustion products of five selected
biomass types, a three or four fold increase in the mercury content has been
observed
Application of halloysite nanotubes in cancer therapy : a review
Halloysite, a nanoclay characterized by a unique, tubular structure, with oppositely charged interior and exterior, suitable, nanometric-range size, high biocompatibility, and low cost, is recently gaining more and more interest as an important and versatile component of various biomaterials and delivery systems of biomedical relevance. One of the most recent, significant, and intensely studied fields in which halloysite nanotubes (HNTs) found diverse applications is cancer therapy. Even though this particular direction is mentioned in several more general reviews, it has never so far been discussed in detail. In our review, we offer an extended survey of the literature on that particular aspect of the biomedical application of HNTs. While historical perspective is also given, our paper is focused on the most recent developments in this field, including controlled delivery and release of anticancer agents and nucleic acids by HNT-based systems, targeting cancer cells using HNT as a carrier, and the capture and analysis of circulating tumor cells (CTCs) with nanostructured or magnetic HNT surfaces. The overview of the most up-to-date knowledge on the HNT interactions with cancer cells is also given
Paleocene sedimentary record of ridge geodynamics in Outer Carpathian basins (Subsilesian Unit)
The stratigraphic position of the Goryczkowiec Sandstone reflects the Paleocene ridge geodynamics in the Outer Carpathian basins. The Goryczkowiec Sandstone was deposited on the slope of a ridge, known as the Subsilesian Sedimentary Area that originated during reorganization of the Outer Carpathian realm. A Paleocene age of this sand- stone, documented clearly by autochthonous foraminiferal and algal assemblages indicates the time of the final forma- tion of the Subsilesian Ridge. Abundant calcareous material of biogenic origin was transported by turbidity currents into deeper zones. This material includes fragments of carbonate buildups represented by algae, bryozoans and other organisms growing in the shallower part of the ridge. The Goryczkowiec Sandstone, previously known as the Szydłowiec Sandstone, is here redefined as a new lithostratigraphic unit within the Subsilesian Sedimentary Area in the marginal Outer Carpathians in Poland. The new name clarifies the ambivalence in the lithostratigraphic nomenclature
Educational trails of the Racławka Valley Nature Reserve and their potential for geoeducation
The Racławka Valley is located west of Krakow, in the Krakow-Częstochowa Upland. This is a place of high bio- and geodiversity, where various rocks of different ages outcrop in vast excavation pits, narrow gorges or form characteristic monadnocks. The richness of various morphological forms and special habitats led to the constitution of a nature reserve, covering most of the Racławka Valley and adjacent, southern parts of the Szklarka Valley. Three educational trails lead through the reserve, connecting a number of geosites. The Geotourism Students’ Scientific Club (GSSC) from AGH University of Science and Technology examined the usability of these trails for geoeducation. After completing geotourism valorisation, adequate teaching materials were prepared, and different age groups were guided around the trails. Their comprehension has been verified by quizzes and opinions gathered through questionnaires. On the bases of these, the three educational trails were widely described and assessed in respect for their terrain difficulty, accessibility, and infrastructure. Each trail has a leitmotif and a specific theme, however geosites from different trails can be combined together to get a route of a chosen theme. The GSSC also released three new geotourism guidebooks, one for each trail, as a result of AGH rector's grant projects in the years 2018–2020.Dolina Racławki położona jest na zachód od Krakowa, na Wyżynie Krakowsko-Częstochowskiej. Stanowi ona obszar o dużejbio- i georóżnorodności, gdzie rozmaite skały o różnym wieku odsłaniają się w rozległych wyrobiskach, na ścianach wąwozów lub w postaci ostańców. Ze względu na bogactwo form morfologicznych i wykształcone na nich siedliska, większość doliny Racławkii przyległą, południową część doliny Szklarki objęto rezerwatem przyrody. Przez obszar rezerwatu prowadzą trzy ścieżki dydaktyczne łączące szereg geostanowisk. Koło Naukowe Geoturystyka (KNGt) z Akademii Górniczo-Hutniczej zbadało ich przydatność dla geoedukacji. Po dokonaniu waloryzacji geoturystycznej opracowano materiały dydaktyczne, a następnie po ścieżkach oprowadzono różne grupy wiekowe. Za pomocą quizów sprawdzono zrozumienie przez uczestników omawianych tematów, a opinie zebrano w formie ankiet. Działania te umożliwiły dokładne opisanie ścieżek oraz ich ocenę pod kątem trudności terenu, dostępnościi infrastruktury. Każda ze ścieżek ma motyw przewodni, można je jednak z powodzeniem łączyć, by zaplanować trasę o określonej tematyce. KNGt przygotowało też trzy przewodniki geoturystyczne po dolinie Racławki, po jednym dla każdej ze ścieżek, w ramach Grantu Rektora AGH w latach 2018–2020
Work Time of a Crew in European and Polish Law
Employee fatigue increases over time, and contributes to situations that endanger health and even life. Under the determinants of health, the human working environment is mentioned, including the working time, schedule, shifts, rest periods as well as the work pace. The aim of the article is to analyze the existing provisions regarding working time in aviation and it has been restricted to civil aviation mobile personnel, which is understood here as crew members on board of a civil aircraft, employed in a Member State
Developed and validated capillary isotachophoresis method for the rapid determining organic acids in childrens saliva
One of the current challenges facing researchers is the search for alternative biological material, as opposed to routinely and invasively collected (such as blood), as the analysis of the former would provide information about the state of human health, allowing for the diagnosis of diseases in their early stages. With the search for disease biomarkers in alternative materials, the development of newer analytical solutions has been observed. This study aims to develop a reliable analytical method using the capillary isotachophoresis technique for the determination of organic acids in children’s saliva, the presence/elevation of which can be used in the future for diagnostic purposes. Organic acids such as formic, lactic, acetic, propionic, and butyric acid, were determined in the saliva of healthy children without carious lesions. The limit of quantification determined in the validation process was found to vary from 0.05 to 1.56 mg/L, the recoveries at the two levels were determined to vary between 90% and 110% for level I, while for level II the corresponding values of 75% and 106% were found; the presentation, expressed as relative standard deviation values (RSD), did not exceed 5%. The parameters determined while validating the results method indicated that the obtained are reliable. The Red–Green–Blue (RGB) additive color model was used for the evaluation of the method. This comparative analysis allowed us to define the color of the method, which expresses whether it meets the given assumptions and requirements. According to the RGB model, the isotachophoresis method developed requires less reagent input, shorter sample preparation times, and results with lower energy consumption. Thus, the subject procedure may provide an alternative, routine tool for determining organic acids in human saliva, to be applied in the diagnosing of diseases of various etiological origins
The analysis of mercury content in coals and ashes
It is well known that mercury that enters the atmosphere is a serious threat to the natural environment. From the available literature, it can be stated that fossil fuels are among the main carriers of this fuel. The question arises whether it is the right approach. While the enrichment of bituminous coal produces limited amounts of mercury, they are being released into the atmosphere as a result of the combustion of coal. The situation is similar in the case of biomass, which releases large amounts of mercury into the atmosphere when subjected to the combustion process. While bituminous coal is the carrier of mercury, the application of currently known technology, rational production and the use of fossil fuels make it possible to maximally minimize mercury emissions into the atmosphere. This study evaluated the mercury content in the ashes resulting from the combustion of bituminous coal subjected to the enrichment process. The samples were collected from ten mines located in the Polish part of the Upper Silesian Coal Basin (USCB). In total, thirty coal samples and thirty products of the combustion process were examined. All sixty samples were subjected to physicochemical analysis, including: moisture content, ash content, sulfur content, carbon content, and Gross Calorific Value
The Upper Cretaceous Ostravice Sandstone in the Polish sector of the Silesian Nappe, Outer Western Carpathians
The Ostravice Sandstone Member was identified and described as a lithostratigraphic unit in the Polish part of the Outer Carpathians. This division occurs in the lowermost part of the Godula Formation, is underlain by variegated deposits of the Mazák Formation or directly by the Barnasiówka and Lhoty formations, and overlain by the Czernichów Member of the Godula Formation. Domination by thick- and very thick-bedded sandstones, conglomeratic sandstones and conglomerates rich in calcareous clasts, mostly of the Štramberk-type limestones, is typical for the Ostravice Sandstone Member. These deposits are widespread between the Moravskoslezské Beskydy Mountains in the Czech Republic and the Ciężkowice Foothills in Poland. The documentation of the Ostravice Sandstone Member occurrence as well as the petrological, sedimentological features, and inventory of the carbonate clasts are presented here
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