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Number of results: 23
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Abstract

Jotunites (hypersthene monzodiorites/ferromonzodiorites) are rocks coeval with plutonic AMCG (anorthosite– mangerite–charnockite–rapakivi granite) suites, which are characteristic of the Proterozoic Eon. It has been experimentally shown that jotunite magma can be recognised as parental to anorthosites and related rocks: since then, research on these rocks has taken on a particular importance. Jotunites were recently described within the deeply buried c. 1.5 Ga Suwałki and Sejny anorthosite massifs in the crystalline basement of NE Poland. The major and trace element compositions of Polish jotunites show them to have a calc-alkalic to alkali-calcic and ferroan character, with a relatively wide range of SiO2 content (40.56 wt. % up to 47.46 wt. %) and high concentrations of Fe (up to 22.63 wt. % Fe2O3), Ti (up to 4.34 wt. % TiO2) and P (up to 1.46 wt. % P2O5). Slight differences in textural features, mineralogical compositions, and geochemistry of whole-rock jotunite samples from distinct massifs allow us to distinguish two kinds: a primitive one, present in the Sejny Intrusion, and a more evolved one, related to the Suwałki Massif.

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Authors and Affiliations

Anna Grabarczyk
Jadwiga Wiszniewska
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Abstract

StreszczenieW artykule przedstawiam zalety traktowania dyrektywalnej teorii znaczenia (DTZ) jako wspólcześnie rozumianej teorii znaczenia wąskiego. Rozpoczynam od sformułowania siedmiu postulatów, które udana teoria znaczenia wąskiego powinna spełniać. Następnie kontrastuję teorię dyrektywalną z semantyką ról pojeciowych Neda Blocka. Dwa aspekty tej teorii zostają włczone do DTZ - jej naturalizm i dodatkowy, czwarty typ dyrektyw znaczeniowych. W dalszej części artykułu pokazuję jak skorzystanie z DTZ w charakterze teorii znaczenia wąskiego pozwala na uniknięcie pewnych dobrze znanych wad semantyk funkcjonalnych. Na zakończenie pokazuję w jaki sposób zmodyfikowana DTZ spełnia siedem postulatów, od których rozpoczajem, i zarysowuję krótko dalsze drogi rozwoju dla tej teorii.
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Authors and Affiliations

Paweł Grabarczyk
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Abstract

The antifeedant activity of lactones with di- and trimethylcyclohexane system was assessed in choice and no-choice bioassays against Leptinotarsa decemlineata and Alphitobius diaperinus larvae and beetles. The results showed that feeding deterrent activity depends on the structure of the tested compounds. Additional methyl group in the molecule of some compounds influences their activity increase or changes their properties from attractant to deterrent ones. The present results also demonstrate the species and developmental stage dependence of antifeedant activity.
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Authors and Affiliations

Maryla Szczepanik
Małgorzata Grabarczyk
Antoni Szumny
Czesław Wawrzeńczyk
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Abstract

Growing emission requirements are forcing the foundry industry to seek new, more environmentally friendly solutions. One of the

solutions may be the technologies of preparing moulding and core sands using organic biodegradable materials

as binders. However, not only environmental requirements grow but also those related to the technological properties

of moulding sand. Advancing automation and mechanization of the foundry industry brings new challenges related to the moulding sands.

Low elasticity may cause defects during assembly of cores or moulds by the manipulators.

The paper presents the study of flexibility in the room temperature according to new method and resistance to thermal deformation of selfhardening

moulding sands with furfuryl resin, containing biodegradable material PCL. The task of the new additive is to reduce the

moulding sands harmfulness to the environment and increase its flexibility in the room temperature. The impact of the additive and the

effect of the amount of binder on the properties of mentioned moulding sands were analysed. Studies have shown that the use of 5% of

PCL does not change the nature of the thermal deformation curve, improves the bending strength of tested moulding mixtures and

increases their flexibility at room temperature.

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Authors and Affiliations

A. Grabarczyk
K. Major-Gabryś
St.M. Dobosz
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Abstract

The article shows the influence of environment requirements on changes in different foundry moulding sands technologies such as cold

box, self-hardening moulding sands and green sands. The aim of the article is to show the possibility of using the biodegradable materials

as binders (or parts of binders’ compositions) for foundry moulding and core sands. The authors concentrated on the possibility of

preparing new binders consisting of typical synthetic resins - commonly used in foundry practice - and biodegradable materials. According

to own research it is presumed that using biodegradable materials as a part of new binders’ compositions may cause not only lower toxicity

and better ability to reclaim, but may also accelerate the biodegradation rate of used binders. What’s more, using some kinds of

biodegradable materials may improve flexibility of moulding sands with polymeric binder. The conducted research was introductory and

took into account bending strength and thermal properties of furan moulding sands with biodegradable material (PCL). The research

proved that new biodegradable additive did not decrease the tested properties.

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Authors and Affiliations

St.M. Dobosz
A. Grabarczyk
K. Major-Gabryś
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Abstract

The paper presents the impact of biodegradable material - polycaprolactone (PCL) on selected properties of moulding sands. A self-hardening moulding sands with phenol-furfuryl resin, which is widely used in foundry practice, and an environmentally friendly self-hardening moulding sand with hydrated sodium silicate where chosen for testing. The purpose of the new additive in the case of synthetic resin moulding sands is to reduce their harmfulness to the environment and to increase their “elasticity” at ambient temperature. In the case of moulding sands with environmentally friendly hydrated sodium silicate binder, the task of the new additive is to increase the elasticity of the tested samples while preserving their ecological character. Studies have shown that the use of 5% PCL in moulding sand increases their flexibility at ambient temperature, both with organic and inorganic binders. The influence of the new additive on the deformation of the moulding sands at elevated temperatures has also been demonstrated.
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Authors and Affiliations

A. Grabarczyk
S.M. Dobosz
K. Major-Gabryś
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Abstract

This paper focuses on mechanical properties of self hardening moulding sands with furfuryl and alkyd binders. Elasticity as a new

parameter of moulding sands is investigated. With the use of presented testing equipment, it is possible to determine force kinetics and

deformation of moulding sand in real time. The need for this kind of study comes from the modern casting industry. New foundries can be

characterized with high intensity of production which is correlated with high level of mechanization and automatization of foundry

processes. The increasingly common use of manipulators in production of moulds and cores can lead to generation of new types of flaws,

caused by breakage in moulds and cores which could occur during mould assembly. Hence it is required that moulds and cores have high

resistance to those kinds of factors, attributing it with the phenomenon of elasticity. The article describes the theoretical basis of this

property, presents methods of measuring and continues earlier research.

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Authors and Affiliations

St.M. Dobosz
A. Grabarczyk
K. Major-Gabryś
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Abstract

The necessity of obtaining high quality castings forces both researchers and producers to undertake research in the field of moulding sands. The key is to obtain moulding and core sands which will ensure relevant technological parameters along with high environmental standards. The most important group in this research constitutes of moulding sands with hydrated sodium silicate. The aim of the article is to propose optimized parameters of hardening process of moulding sands with hydrated sodium silicate prepared in warm-box technology. This work focuses on mechanical and thermal deformation of moulding sands with hydrated sodium silicate and inorganic additives prepared in warm-box technology. Tested moulding sands were hardened in the temperature of 140oC for different time periods. Bending strength, thermal deformation and thermal degradation was tested. Chosen parameters were tested immediately after hardening and after 1h of cooling. Conducted research proved that it is possible to eliminate inorganic additives from moulding sands compositions. Moulding sands without additives have good enough strength properties and their economic and ecological character is improved.
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Authors and Affiliations

K.A. Major-Gabryś
S.M. Dobosz
A.P. Grabarczyk
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Abstract

The constantly developing and the broadly understood automation of production processes in foundry industry, creates both new working conditions - better working standards, faster and more accurate production - and new demands for previously used materials as well as opportunities to generate new foundry defects. Those high requirements create the need to develop further the existing elements of the casting production process. This work focuses on mechanical and thermal deformation of moulding sands prepared in hot-box technology. Moulding sands hardened in different time periods were tested immediately after hardening and after cooling. The obtained results showed that hardening time period in the range 30-120 sec does not influence the mechanical deformation of tested moulding sands significantly. Hot distortion tests proved that moulding sands prepared in hot-box technology can be characterized with stable thermal deformation up to the temperature of circa 320oC.

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Authors and Affiliations

A. Grabarczyk
K. Major-Gabryś
S.M. Dobosz
J. Jakubski
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Abstract

Modern techniques of castings production, including moulding sands production, require a strict technological regime and high quality

materials. In the case of self-hardening moulding sands with synthetic binders those requirements apply mainly to sand, which adds to

more than 98% of the whole moulding sand mixture. The factors that affect the quality of the moulding sands are both chemical (SiO2

,

Fe2O3 and carbonates content) and physical. Among these factors somewhat less attention is paid to the granulometric composition of the

sands. As a part of this study, the effect of sand quality on bending strength Rgu

and thermal deformation of self-hardening moulding sands

with furfural and alkyd resin was assessed. Moulding sands with furfural resin are known [1] to be the most susceptible to the sand quality.

A negative effect on its properties has, among others, high content of clay binder and so-called subgrains (fraction smaller than 0,1mm),

which can lead to neutralization of acidic hardeners (in the case of moulding sands with furfuryl resin) and also increase the specific

surface, what forces greater amount of binding agents. The research used 5 different quartz sands originating from different sources and

characterized with different grain composition and different clay binder content.

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Authors and Affiliations

St.M. Dobosz
A. Grabarczyk
J. Jakubski
K. Major-Gabryś
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Abstract

The constant growth of foundry modernization, mechanization and automation is followed with growing requirements for the quality and parameters of both moulding and core sands. Due to this changes it is necessary to widen the requirements for the parameters used for their quality evaluation by widening the testing of the moulding and core sands with the measurement of their resistance to mechanical deformation (further called elasticity). Following article covers measurements of this parameter in chosen moulding and core sands with different types of binders. It focuses on the differences in elasticity, bending strength and type of bond destruction (adhesive/cohesive) between different mixtures, and its connection to the applied bonding agent. Moulding and cores sands on which the most focus is placed on are primarily the self-hardening moulding sands with organic and inorganic binders, belonging to the group of universal applications (used as both moulding and core sands) and mixtures used in cold-box technology.

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Authors and Affiliations

St.M. Dobosz
A. Grabarczyk
K. Major-Gabryś
J. Kusiński
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Abstract

The ablation casting technology consists in pouring castings in single-use moulds made from the mixture of sand and watersoluble binder. After pouring the mould with liquid metal, while the casting is still solidifying, the mould destruction (washing out, erosion) takes place using a stream of cooling medium, which in this case is water. The following paper focuses on the selection of moulding sands with hydrated sodium silicate technologies for moulds devoted to the ablation casting of aluminum alloys. It has been proposed to use different types of moulding sands with a water-soluble binder, which is hydrated sodium silicate. The authors showed that the best kind of moulding sands for moulds for Al alloy casting will be moulding sands hardened with physical factors – through dehydration. The use of microwave hardened moulding sands and moulding sands made in hot-box technology has been proposed. The tests were carried out on moulding sands with different types of modified binder and various inorganic additives. The paper compares viscosity of different binders used in the research and thermal degradation of moulding sands with tested binders. The paper analyzes the influence of hardening time periods on bending strength of moulding sands with hydrated sodium silicate prepared in hot-box technology. The analysis of literature data and own research have shown that molding sand with hydrated sodium silicate hardened by dehydration is characterized by sufficient strength properties for the ablation foundry of Al alloys.

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Authors and Affiliations

K. Major-Gabryś
M. Hosadyna-Kondracka
A. Grabarczyk
J. Kamińska
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Abstract

We used the Dpph method to assess in vitro the antiradical activity of extracts from the roots, leaves and fruits of six Rumex L. (dock) species. Data from preliminary screening indicated that all the tested extracts showed antioxidant properties. The degree of antiradical activity depended upon the plant part. Fruit extracts from R. hydrolapathum Huds., R. obtusifolius L. and R. confertus Willd. showed stronger antiradical properties than the other tested material. We also determined tannin content levels in the extracts and their correlation with antioxidant activity.

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Authors and Affiliations

Magdalena Wegiera
Paweł Grabarczyk
Barbara Baraniak
Helena Smolarz
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Abstract

Casting industry has been enriched with the processes of mechanization and automation in production. They offer both better working standards, faster and more accurate production, but also have begun to generate new opportunities for new foundry defects. This work discusses the disadvantages of processes that can occur, to a limited extend, in the technologies associated with mould assembly and during the initial stages of pouring. These defects will be described in detail in the further part of the paper and are mainly related to the quality of foundry cores, therefore the discussion of these issues will mainly concern core moulding sands. Four different types of moulding mixtures were used in the research, representing the most popular chemically bonded moulding sands used in foundry practise. The main focus of this article is the analysis of the influence of the binder type on mechanical and thermal deformation in moulding sands.

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Authors and Affiliations

A. Grabarczyk
K. Major-Gabryś
S.M. Dobosz
J. Jakubski
D. Bolibruchová
M. Bruna
R. Pastirčák
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Abstract

The essence of ablation casting technology consists in pouring castings in single-use moulds made from the mixture of sand and a watersoluble binder. After pouring the mould with liquid metal, while the casting is still solidifying, the mould destruction (washing out, erosion) takes place using a stream of cooling medium, which in this case is water. This paper focuses on the selection of moulding sands with hydrated sodium silicate for moulds used in the ablation casting. The research is based on the use of Cordis binder produced by the Hüttenes-Albertus Company. It is a new-generation inorganic binder based on hydrated sodium silicate. Its hardening takes place under the effect of high temperature. As part of the research, loose moulding mixtures based on the silica sand with different content of Cordis binder and special Anorgit additive were prepared. The reference material was sand mixture without the additive. The review of literature data and the results of own studies have shown that moulding sand with hydrated sodium silicate hardened by dehydration is characterized by sufficient strength properties to be used in the ablation casting process. Additionally, at the Foundry Research Institute in Krakow, preliminary semi-industrial tests were carried out on the use of Cordis sand technology in the manufacture of moulds for ablation casting. The possibility to use these sand mixtures has been confirmed in terms of both casting surface quality and sand reclamation.

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Authors and Affiliations

M. Hosadyna-Kondracka
K. Major-Gabryś
J. Kamińska
A. Grabarczyk
M. Angrecki
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Abstract

Casting industry has been enriched with the processes of mechanization and automation in production. They offer both better working standards, faster and more accurate production, but also have begun to generate new opportunities for new foundry defects. This work discusses the disadvantages of processes that can occur, to a limited extend, in the technologies associated with mould assembly and during the initial stages of pouring. These defects will be described in detail in the further part of the paper and are mainly related to the quality of foundry cores, therefore the discussion of these issues will mainly concern core moulding sands. Four different types of moulding mixtures were used in the research, representing the most popular chemically bonded moulding sands used in foundry practise. The main focus of this article is the analysis of the influence of the binder type on mechanical and thermal deformation in moulding sands.
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Authors and Affiliations

A. Grabarczyk
1
ORCID: ORCID
K. Major-Gabryś
1
ORCID: ORCID
J. Jakubski
1
ORCID: ORCID
St.M. Dobosz
1
ORCID: ORCID
D. Bolibruchová
2
ORCID: ORCID
R. Pastirčák
2
ORCID: ORCID

  1. AGH University of Science and Technology, Faculty of Foundry Engineering, Department of Moulding Materials, Mould Technology and Foundry of Non-ferrous Metals, Al. Mickiewicza 30, 30-059 Krakow, Poland
  2. University of Zilina, Žilinská Univerzita v Žiline, Faculty of Mechanical Engineering, Žilina, Slovak Republic

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