The experiment consisted in monitoring the count of moulds and three selected Trichoderma sp. isolates (T1 - Trichoderma atroviride, T2 - Trichoderma harzianum, T3 - Trichoderma harzianum) in vegetable (onion and tomato) waste composted with additives (straw, pig manure). Additionally, the aim of the study was to determine the type of interaction occurring between autochthonous fungi isolated from composts after the end of the thermophilic phase and Trichoderma sp. strains applied in the experiment. Number of microorganisms was determined by the plate method, next the identification was confirmed. The rating scale developed by Mańka was used to determine the type of interactions occurring between microorganisms. The greatest count of moulds in onion waste composts was noted in the object which had simultaneously been inoculated with two strains T1 - T. atroviride and T3 - T. harzianum. The greatest count of moulds was noted in the tomato waste composts inoculated with T2 - T. harzianum strain. Microscope identification revealed that Penicillum sp., Rhizopus sp., Alternaria sp. and Mucor sp. strains were predominant in onion waste composts. In tomato waste composts Penicillium was the predominant genus, followed by Rhizopus. The test of antagonism revealed the inhibitory effect of Trichoderma isolates on most autochthonous strains of moulds. Tomato waste composts proved to be better substrates for the growth and development of Trichoderma sp. isolates. The results of the study show that vegetable waste can be used in agriculture as carriers of antagonistic microorganisms.

The aim of this research was to evaluate the microbiological indoor air contamination level in chosen facilities of the primary health-care for adults and children. The total numbers of mesophilic bacteria, staphylococci, coli-group bacteria and moulds in both surgery rooms and patients’ waiting rooms were determined. Air samples were collected with a MAS 100 impactor and the concentration of microorganisms was estimated by a culture method. The microbiological air contamination level was diverse: the number of mesophilic bacteria ranged from 320 to 560 CFU/m3, number of staphylococci - 10-305 CFU/m3, coli group bacteria - 0-15 CFU/m3 and moulds - 15-35 CFU/m3. The bacteriological contamination level of the air in examined community health centers was higher than described in the literature for hospitals and exceeded the acceptable values proposed for the surgery objects.

While analyzing shape accuracy of ferroalloy precision castings in terms of ceramic moulds physical anisotropy, low-alloy steel castings

("cover") and cast iron ("plate") were included. The basic parameters in addition to the product linear shape accuracy are flatness

deviations, especially due to the expanded flat surface which is cast plate. For mentioned castings surface micro-geometry analysis was

also carried, favoring surface load capacity tp50 for Rmax = 50%.

Surface load capacity tp50 obtained for the cast cover was compared with machined product, and casting plate surface was compared with

wear part of the conveyor belt. The results were referred to anisotropy of ceramic moulds physical properties, which was evaluated by

studying ceramic moulds samples in computer tomography equipment Metrotom 800.

The obtained results of heating of sand moulds with binders by means of a thermal radiation of liquid metal are presented in this study.

Standard samples for measuring Rg made of the tested moulding sands were suspended at the lower part of the cover which was covering

the crucible with liquid metal (cast iron), placed in the induction furnace. The authors own methodology was applied in investigations. The

progressing of the samples surface layers heating process was determined as the heating time function. Samples of a few kinds of

moulding sands with chemical binders were tested. Samples without protective coatings as well as samples with such coatings were tested.

The influence of the thermal radiation on bending resistance of samples after their cooling was estimated. The influence of several

parameters such as: time of heating, distance from the metal surface, metal temperature, application of coatings, were tested. A very fast

loss of strength of moulding sands with organic binders was found, especially in cases when the distance between metal and sample

surfaces was small and equaled to 10÷15 mm. Then, already after app. 15 seconds of the radiation (at Tmet=1400o

C), the resistance

decreases by nearly 70%. Generally, moulding sands with organic binders are losing their strength very fast, while moulding sands with

water glass at first increase their strength and later slightly lose. The deposition of protective coatings increases the strength of the mould

surface layers, however does not allow to retain this strength after the metal thermal radiation.

This article investigates possible use of waste gypsum (synthetic), recovered via flue-gas desulfurization from coal-fired electric power plants, in foundries. Energy sector, which in Eastern Europe is mostly composed from coal-fired electric power plants, is one of the largest producers of sulfur dioxide (SO2). In order to protect the environment and reduce the amount of pollution flue-gas desulfurization (FGD) is used to remove SO2 from exhaust flue gases of fossil-fuel power plants. As a result of this process gypsum waste is produced that can be used in practical applications. Strength and permeability tests have been made and also in-depth analysis of energy consumption of production process to investigate ways of preparing the synthetic gypsum for casting moulds application. This paper also assesses the chemical composition, strength and permeability of moulds made with synthetic gypsum, in comparison with moulds made with traditional GoldStar XL gypsum and with ceramic molds. Moreover examination of structure of synthetic gypsum, the investigations on derivatograph and calculations of energy consumption during production process of synthetic gypsum in wet flue-gas desulfurization were made. After analysis of gathered data it’s possible to conclude that synthetic gypsum can be used as a material for casting mould. There is no significant decrease in key properties, and on the other hand there is many additional benefits including low energy consumption, decreased cost, and decreased environmental impact.

The work presents the results of the studies of Co-Cr-Mo casting alloys used in the production of frame casts of removable dentures,

crowns and bridges in dental prosthetics. The studies were performed on four Co-Cr-Mo alloys of different contents of Mo, W and other

additives. Electrochemical tests were performed, which aimed at examining the corrosion resistance of the alloys and observing the alloy

structure after chronoamperometric tests with the potential in the area of the occurrence of the passive layer breakpoint. The alloy

microstructure images after chronoamperometric tests show the presence of non-uniformly distributed general corrosion. Moreover, a

project of cobalt alloy casting was elaborated using a ceramic mold casting. Additionally, analysis of the obtained microstructure was

performed. The microstructure of the examined alloys was of the dendrite type. This microstructure was chemically inhomogeneous and

consisted of an austenitic matrix formed by a solid cobalt solution and chromium in the core dendritic structure.

The results of testing the strength properties of experimental ceramic materials containing spending moulding sand after initial mechanical reclamation as a material for subsequent layers of the stucco composition were presented. Tests were carried out on spent moulding sands from various foundry technologies, i.e. sand with furfuryl resin and sand with hydrated sodium silicate. The spent, agglomerated moulding sand has undergone a crushing process. Next, the required granular fractions used for individual layers of the stucco material were separated. Ceramic samples, in which the spent moulding sand was a substitute for fresh silica sand in successive layers of the stucco composition, were prepared. As a reference material, identical ceramic samples were used but with all layers made from the fresh silica sand. Samples prepared in this way were used to determine the bending strength of ceramic materials in the temperature range from 20 to 900ºC. The obtained values of the bending strength have demonstrated that spent moulding sand can be used in investment casting with no adverse effect on the strength of ceramic materials.

The investigation results of the kinetics of binding ceramic moulds, in dependence on the solid phase content in the liquid ceramic slurries being 67, 68 and 69% - respectively, made on the basis of the aqueous binding agents Ludox AM and SK. The ultrasonic method was used for assessing the kinetics of strengthening of the multilayer ceramic mould. Due to this method, it is possible to determine the ceramic mould strength at individual stages of its production. Currently self-supporting moulds, which must have the relevant strength during pouring with liquid metal, are mainly produced. A few various factors influence this mould strength. One of them is the ceramic slurry viscosity, which influences a thickness of individual layers deposited on the wax model in the investment casting technology. Depositing of layers causes increasing the total mould thickness. Therefore, it is important to determine the drying time of each deposited layer in order to prevent the mould cracking due to insufficient drying of layers and thus the weakening of the multilayer mould structure.

The study discusses the issues connected with the production of thin-walled ceramic slurry in the replicast cs technology. In the ceramic mould production process, a special role is played by the liquid ceramic slurry used to produce the first layer of the mould. The study examines selected technological properties of liquid ceramic slurries used to produce moulds in the replicas cs technology. The ceramic slurries for the tests were prepared based on the binders Ludox Px30 and Sizol 030, enriched with Refracourse flour. The wettability of the pattern's surface by the liquid ceramic slurry and the dependence of the apparent viscosity on the ceramic flour content in the mixture were determined. The wettability of the pattern surface by the liquid ceramic slurry was determined based on the measurement of the wetting angle. The angle was determined by means of an analysis of the computer image obtained with the use of a CDC camera.

In contrast to casting to conventional non-reusable “sand” moulds, for which calculating technique for an optimum design of the gating system is comparatively well-developed, a trial-and-error method is applied mostly for casting to ceramic shell moulds made by the investment casting technology. A technologist selects from gating systems of several types (that are standardized by the foundry mostly) on the basis of experience. However, this approach is not sustainable with ever growing demands on quality of castings and also the economy of their fabrication as well as with new types of complex sizeable castings introduced to the production gradually (by new customers from the aircraft industry above all) any more. The simulation software may be used as a possible tool for making the process of optimising gating systems more effective.

During excavation of the cremation cemetery of urnfield culture in Legnica at Spokojna Street (Lower Silesia, Poland), dated to 1100-700

BC, the largest - so far in Poland – a collection of casting moulds from the Bronze Age was discovered: three moulds for axes casting

made out of stone and five moulds for casting sickles, razors, spearhead and chisels, made out of clay. This archaeological find constituted

fittings of foundrymen’s graves. In order to perform the complete analysis of moulds in respect of their application in the Bronze Age

casting technology analytical methods, as well as, computer aided methods of technological processes were used. Macroscopic

investigations were performed and the X-ray fluorescence spectrometry method was used to analyse the chemical composition and metal

elements content in mould cavities. Moulds were subjected to three-dimensional scanning and due to the reverse engineering the geometry

of castings produced in these moulds were obtained.

The gathered data was used to perform design and research works by means of the MAGMA5

software. Various variants of the pouring

process and alloys solidification in these archaeological moulds were simulated. The obtained results were utilised in the interpretation of

the Bronze Age casting production in stone and clay moulds, with regard to their quality and possibility of casting defects occurrence

being the result of these moulds construction.

The reverse engineering, modelling and computer simulation allowed the analysis of moulds and castings. Investigations of casting moulds

together with their digitalisation and reconstruction of casting technology, confirm the high advancement degree of production processes

in the Bronze Age.