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Number of results: 10
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Abstract

In vitro embryogenic callus is a critical factor for genetic transformation of rice, especially for indica varieties. In this study, we investigated the relationship between polyamines, including putrescine (Put), spermidine (Spd) and spermine (Spm), and callus browning, and we studied the effect of exogenous Put on callus regeneration and on the content of endogenous polyamines. In addition, the expression levels of arginine decarboxylase gene (Adcl) and S-adenosylmethionine decarboxylase gene (Samdc) in embryogenic callus were studied by quantitative Real-time PCR analysis. The results showed that the contents of endogenous Put and Spd in the browning callus were significantly lower than those in normal callus. Exogenous Put could effectively improve the growing state of callus of indica rice and enhance the development of embryogenic callus. The content of endogenous polyamines in embryogenic callus, especially Spd and Spm, was increased after addition of exogenous Put. Additionally, exogenous Put also had an obvious impact on the expression levels of Adcl but partial effect on the expression levels of Samdc gene. This study could increase the knowledge of both embryogenic callus induction and polyamine catabolism in callus in indica rice.

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Authors and Affiliations

YP Tan
W Hu
X Xu
J Zhou
CT Wang
XQ Liu
G Cheng
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Abstract

Thin coal seams found in the Lions Cove Formation, Polonia Glacier Group (Middle Eocene, upper part) at King George Bay, King George Island (South Shetland Islands, West Antarctica), represent lustrous (vitrine) brown-coal metaphase. The coal from the lower seam represents carbonized wood, probably angiosperm, that from the upper ones originated due to accumulation of branches or larger wood fragments and leaf remains. These coals are slightly older than metaxylite brown coal previously described from Admiralty Bay on King George Island, and dated at Eocene-Oligocene boundary. Both coal occurrences are evidences for a warm climate which prevailed in the Antarctic Peninsula sector during the Arctowski Interglacial (ca 50—32 Ma).

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Authors and Affiliations

Krzysztof Birkenmajer
Jerzy K. Frankiewicz
Marian Wagner
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Abstract

The paper presents brown coal as one of the two basic domestic energy raw materials apart from hard coal. Historically, the use of brown coal in Poland is primarily fuel for the power plants. It was used for the production of lignite briquettes in small quantities and as fuel for local boiler houses and as an addition to the production of fertilizers (Konin and Sieniawa). At present, after changes in the case of the quality of fuels used in local boiler plants, brown coal remains as a fuel for the power plants in almost 100%. Currently, the brown coal industry produces about 35% of the cheapest electricity. The cost of electricity production is more than 30% lower than the second basic fuel – hard coal. The existing fuel and energy complexes using brown coal, with the Bełchatów complex at the forefront, are now an important guarantor of Poland’s energy security. In contrast to the other fuels such as: oil, natural gas or hard coal, the cost of electricity production from brown coal is predictable in the long term and almost insensitive to fluctuations in global commodity and currency markets. Its exploitation is carried out using the high technological solutions and respecting all environmental protection requirements, both in the area of coal extraction and electricity generation. Importantly, the fuel and energy complexes using brown coal showed a positive profitability so far and generated surpluses enabling the financing of maintenance and development investments, also in other energy segments. In particular, the sector did not require and has yet not benefited from public aid in the form of, for example, subsidies or tax concessions. Polish brown coal mining has all the attributes necessary for long-term development to ensure the country’s energy security. The document which is a road map for the brown coal industry is the Program for the Brown Coal Mining Sector in Poland adopted by the Council of Ministers on May 30, 2018. The Program covers the years 2018–2030 with a perspective up to 2050 and presents the development directions of the brown coal mining sector in Poland together with the objectives and actions necessary to achieve them. The Program presents a strategy for the development of brown coal mining in Poland in the first half of the 21st century. Possible scenarios have developed in active mining and energy basins as well as in new regions with significant resources of this mineral. This is to enable the most efficient use of deposits in the Złoczew and Konin regions as well as the Gubin and Legnica brown coal basins, and then deposits located in the Rawicz region (Oczkowice) as well as other prospective areas that may eventually replace the existing active mining and energy areas. This will allow power plants to continue to produce inexpensive and clean electricity, using the latest global solutions in the field of clean coal technologies.

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Authors and Affiliations

Zbigniew Kasztelewicz
Miranda Ptak
Mateusz Sikora
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Abstract

Coal reserves in the Czech Republic are estimated to be 10 billion tons – hard coal about 37%, brown coal about 60% and lignite 3%. Hard coal is produced in Northern Moravia. In 2017 the production of hard coal was 5.5 million tons. Brown coal is mined in North-Western Bohemia − the production of brown coal in 2017 was 38.1 million tons. Significant quantities of hard coal are exported to: Slovakia, Austria, Germany and Hungary. In accordance with the National Energy Policy, coal will remain the main source of energy in the country in the future, despite the increased use of nuclear energy and natural gas. The government expects that in 2030 energy from coal will account for 30.5% of energy produced. There are five coal companies in the Czech Republic: OKD, a.s., the only hard coal producer and four brown coal mining companies: Severočeské Doly a.s., owned by ČEZ, the largest producer of brown coal, Vršanská uhelná a.s., with coal resources until 2055, Severní energetická a.s. with the largest brown coal reserves in the Czech Republic and Sokolovska uhelná a.s., the smallest mining company extracting lignite. OKD operates coal in two mines Kopalnia Důlní závod 1 – (consists of three mines: ČSA Mine, Lazy Mine, Darkov Mine) and Mine Důlní závod 2 (ttwo mines Sever, Jih). The article also presents a pro-ecological solution for the management of waste heaps after coal enrichment – a plant for the enrichment of coal waste from the Hermanice heap.

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Authors and Affiliations

Vladimír Čablík
Miluše Hlavatá
Iva Janáková
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Abstract

According to International Energy Agency (IEA) energy security is the continuous supply of energy at acceptable prices. National energy is based primarily on its own energy resources such as hard coal and brown coal. The 88% of electric energy production from these minerals gives us full energy independence. Additionally, the energy production costs from these raw materials are the lowest compared to other technologies. Of these two, the energy produced from brown coal is characterized by the lowest unit technical generating cost. Poland has the resources of these minerals for decades to come, the experience related to mining and processing them, scientific and design facilities and technical facilities and factories producing machines and equipment for their own needs, as well as for export. Coal is and should remain an important source of electricity and heat supply in Poland for the next 25–50 years. It is one of the most reliable and profitable energy sources. This policy may be difficult in the next decades due to the exhaustion of the available resources of hard and brown coal. The conditions for the construction of new mines, and thus for the development of coal mining in Poland, are very interdisciplinary in legal, environmental, economic and reputational terms. Germany has similar problems. Despite the fact that it is an image of a country investing in renewable energy sources, which are pioneers of energy production from RES, in reality hard and brown coal are still the primary sources utilized to produce electric energy.

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Authors and Affiliations

Zbigniew Kasztelewicz
Miranda Ptak
Mateusz Sikora
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Abstract

The open-cast nature of deposit exploitation means that apart from the extraction of the main mineral, rocks are also found in its vicinity. Their nature, raw material quality and geological and mining conditions allow them to be used in various branches of the economy. Hence, it seems that more attention should now be given to these rocks. However, the long-term, open-cast mining operations involving Bełchatów lignite ultimately necessitated basic, raw-material-related research on the deposits accompanying the lignite as the main mineral. The presented work shows the state of the recognition of rocks lying in the Mesozoic–Neogene contact zone in the Bełchatów lignite deposit as well as their petrographic nature and possible directions of their use. Attention was drawn to the lithological diversity of the studied rocks and diagenetic processes that contributed to the impact on their physical and mechanical characteristics. Based on the analysis of the literature, the current state of utilization and development as well as the balance of accompanying rock resources in the Bełchatów lignite deposit are presented.

Today, it would seem very important from various economic points of view for utilization and management of the aforementioned rocks encountered as open-cast lignite mining to take place. Natural resources are protected where the area mined is kept in check, and there is economic significance to any increasing in the supply of minerals, or materials made from them. The level of profitability for economic entities that exploit lignite deposits may obviously be raised in this way, and environmental goals can also be served if some of what is extracted can be transformed into environment-friendly materials.

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Authors and Affiliations

Agnieszka Pękala
ORCID: ORCID
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Abstract

In years 1998-2000 the pot experiment was carried out. The aim of this investigation was to determine the influence of brown coal, waste activated sludge, their mixtures and farmyard manure on the content of Cr and Ni in soil material and in the dry mass of Lolium multiflorum Krato variety. The pots were filled with loamy sand as soil material, brown coal which had low energetic value from Sieniawa and Konin mines. waste activated sludges were taken from mechanical-biological sewage purification plants located at Siedlce, Luków and Drosed (poultry processing plant) and mixed farmyard manure. In each year of experiment four cuts were harvested. The total content of Cr and Ni in soil materials and in dry mass of grass after dry combustion of samples was determinate by !CP-AES method on spectrometer Optima 3200 RL manufactured by Perkins-Elmer. The highest content of Cr and Ni was determinate in soil materials from objects fertilized with waste activated sludge from Siedlce. The average content of Cr in dry mass of grass reached 5.15 mg/kg and Ni 3.05 mg/kg.
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Authors and Affiliations

Stanisław Kalembasa
Barbara Symanowicz
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Abstract

Global brown coal resources are estimated to be extracted at around 512 million Mg. They are found in over a dozen countries, including primarily: Australia, China, the Czech Republic, Greece, Germany, Poland, Russia, the United States and Turkey. More than 80% of total brown coal production in the EU takes place in: Germany, Poland, Greece and the Czech Republic. This means that the majority of production still uses conventional fuels, including both hard coal and brown coal. Given the current energy needs in the context of brown coal reserves depletion and the impacts of the current climate and energy policies of the EU, it is very important that all new investments in mining and energy complexes based on brown coal resources must be prepared carefully to ensure high production efficiency and minimize negative environmental impacts. This article attempts to solve a problem involving the choice of the location of the opening cut to expose brown coal deposits. Due to the stratified nature of brown coal deposits and the associated open-cast mining technology used in a continuous mining system with bucket wheel excavators, belt conveyor systems and spreaders, the location of the opening cut is not completely random and the number of potential solutions is finite. The multifaceted technical, organizational, economic, social and environmental problems require a holistic approach to this research problem. Such an approach should take the different, often opposing, perspectives of the many stakeholders into account. These issues can be solved using mathematical tools designed for multiple-criteria decision support. With the proposed method, a ranking of alternatives can be created, depending on the predefined location of the opening cut.

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Authors and Affiliations

Mateusz Henryk Sikora
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Abstract

The national power industry is based primarily on its own energy mineral resources such as hard and brown coal. Approximately 80% of electrical energy production from these minerals gives us complete energy independence and the cost of its production from coal is the lowest in comparison to other sources. Poland has, for many decades had vast resources of these minerals, the experience of their extraction and processing, the scientific-design facilities and technical factories manufacturing machines and equipment for own needs, as well as for export. Nowadays coal is and should be an important source of electrical energy and heat for the next 25–50 years, because it is one of the most reliable and price acceptable energy sources. This policy may be disturbed over the coming decades due to the depletion of active resources of hard and brown coal. The conditions for new mines development as well as for all coal mining sector development in Poland are very complicated in terms of legislation, environment, economy and image. The authors propose a set of strategic changes in the formal conditions for acquiring mining licenses. The article gives a signal to institutions responsible for national security that without proposed changes implementation in the legal and formal process it, will probably not be possible to build next brown coal, hard coal, zinc and lead ore or other minerals new mines.

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Authors and Affiliations

Zbigniew Kasztelewicz
Antoni Tajduś
ORCID: ORCID
Marek Cała
ORCID: ORCID
Miranda Ptak
Mateusz Sikora
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Abstract

In this article, I reflect on recent discussions of the methodological status of scientific knowledge within and outside the Academy. I draw attention to the problem of declining public trust in science (risk and fear society) and the phenomenon of post-truth. In the context of these issues, I present three positions whose authors define the relationship between official academic science in relation to other forms of knowledge (lay people) and forms of knowledge use outside the Academy (politics). The first position termed “elective modernism” was formulated by Harry Collins and Robert Evans in the context of discussions of the third wave of science disputes. Elective modernism defines the way in which policy decisions are made on the recommendations of scholars who have a methodological self-awareness of the possibilities and limitations of scientific knowledge. The second position is Steve Fuller's proposal of protestant science as a form of science in the context of posttruth conditions. In this view, knowledge can be produced by anyone, but it must meet certain specified scientific criteria. The third position is the view of expert knowledge proposed by Mark R. Brown, as a representation of various worldview or cultural options, whose representatives commission experts to make appropriate recommendations for certain political decisions.
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Authors and Affiliations

Rafał Paweł Wierzchosławski
1

  1. Liberal Arts and Sciences, Collegium Historicum UAM, Poznań

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