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The salts of dicarboxylic acids with alkaline earth metals are not very thoroughly studied and only a few such compounds are well known and characterized. In this work a detailed examination of the infrared spectra recorded at room temperature (RT) and at the liquid nitrogen boiling temperature (LNT) and Raman spectra (at room temperature) of the monohydrates of strontium and barium pimelates, [Sr(μ6-C7H10O4)(H2O)]n and [Ba(μ6-C7H10O4)(H2O)]n respectively, has been carried on. These isostructural salts are important nucleating agents for processing of isotactic polypropylene (iPP). The vibrational spectra of the two salts have been interpreted by using factor group analysis. For more correct and unequivocal interpretation of the vibrational spectra, samples containing partially and almost fully deuterated crystallization water have also been prepared and studied. The effect of the metal ion on the vibrations of the pimelic acid ion as well as the strength of the hydrogen bonds formed by the crystallization water molecule has been discussed.

Ba, Sr, Ca and Mg pimelates were used as nucleators for the crystallization of isotactic polypropylene. The pimelates were synthesized as described earlier [1] and they were obtained as white powders. Their average grain size and distribution were determined, and for Ca- and Ba-pimelates the grain size was less than 10 m, while larger dimensions were found for Mg- and Sr-pimelates (29 and 22 m). Isothermal crystallization of polypropylene was analyzed by DSC. The crystallization was carried out at the Tc in the range from 397K to 406 K. Based on the determined values for the enthalpy of crystallization, the extent of crystallization (crystal conversion) was calculated and the half-time of crystallization (t0.5) was determined and used as a parameter to compare the rate of crystallization in differently nucleated systems. It was shown that the value of t0.5 for Ca-pimelate nucleated polyprolylene was lower than for all other nucleated systems. The content of the β-crystalline phase in polypropylene nucleated with different pimelates has a decreasing tendency with the increasing of crystallization temperature, Tc. The equilibrium melting temperature for the nucleated polypropylene was in the range T0m=446-455 K, lower than for non-nucleated isotactic polypropylene (460 K).

The pimelates of the eart-alkaline elements and pimelic acid have been synthesized and studied. All prepared pimelates are crystallohydrates and Ba and Sr pimelate are isomorphous. The obtained compounds have been characterized using FIR and Raman spectroscopy and X-ray diffraction and it was found that, at the melt temperature of polypropylene, the pimelates of Ba and Sr are crystalline whereas the ones of Ca and Mg are amorphous. The nucleation activity of these pimelates have been studied in the process of crystallization of polypropylene in non-isothermal conditions and followed by differential scanning calorimetry (at rate of crystallization Vc= 1-20 K/min). It was found that their nucleation activity, even at concentration of 0.1 %, differs considerably with regards to the crystallization rate, and they induce different polymorphic composition of the polymer. The nucleation activity was mostly exhibited by Ca pimelate, and when it was used the content of the β crystalline phase (Uβ) in polyprolylene ranged from 0.90 to 0.94, depending on the crystallization rate, compared to 0.18-0.35 when Mg pimelate was used. In the polymer obtained by using Ba and Sr pimelate, Uβ ranged from 0.47 to 0.77. Based on the structures of the pimelates and the theoretical concepts for nucleation activity of solid substrates, an attempt was made to correlate the obtained activity to the structural parameters of the obtained polymer.

In this work we report the results of our investigation on new materials for the production of piston valves with much better dynamic properties and lesser energy consumption as compared to the traditional ones made of metals. Fiber reinforced polymer matrix composite materials with thin hard surface coatings have been developed and tested for manufacturing of hydraulic and pneumatic piston valves. The analysis has shown that the valves, actuated by a piezoelectric actuator consumes much less electric energy than the valve, actuated by the electro magnets and also achieves better dynamic characteristics.

The main goal of De_Amatech Eureka project is to develop new actuators and new materials, a^s well as technology, for the production of piston valves with much better dynamic properties and lesser energy consumption as compared to the traditional ones made of metals [1]. In this work we report the results of our investigation on model systems advanced material/surface coating. Several types of advanced materials have been developed and tested for manufacturing of parts for pneumatic and hydraulic valves, and theil' basic mechanical properties have been determined. Attempts have been made to use FTIR and micro-Raman spectroscopy for characterization of these systems aimed for the productioir of the alternative materials for piston valves. PVD magnetron sputtering metal targets were used in order to find best solution for the application of an appropriate thin coating on the sudace of the samples. Characterization of the abrasion resistance of the coated samples was perfotmed using internal methods developed by EUREKA partners. Testing of the surface microhardness of the coated materials was performed in order to evaluate the quality of the coatings.

The main goal of DE_AMATECH EUREKA project is to develop new actuators and new materials, as well as technology, for the production of piston valves with much better dynamic properties and lower energy consumption compared to the traditional valves made of metals. one of the major parts of the whole valve assembly is the piston itself, which contribution to reaching the main goal of the whole project is of crucial importance. The main requirements for the piston are: to be lighter than the metal counterparts; to withstand the working pressureof the valve; to be friction and abrasion resistant - the property which is directly related to the working life of the piston on one hand, and as well as that of the whole assembly (calve) on the other hand. To meet these requirements we have taken two distinctive different approaches: the first one is, to develop an alternative/advanced material or to choose existing engineering material which will be coated with hard metal layer. This material, besides its mechanical strength to withstand internal (working) pressure of the valve, must be hard enough nd high temperature resistant so that it will wiyhstand the coating process, which requires hard substrate and high temperature resistance of the coated material. The second one is to develop an alternative/advanced material which will meet the exploitation requirements for the piston without being metal coated i.e. only "pure" material. The materials besides its mechanical strength to withstand internal (working) pressure of the valve, must be friction and abrasion resistant; must be capable of undergoing precise maching and must not swell when dipped in hydraulic oil i.e. must have very good dimension stability during the working cycle of the valve. In this work we report the results of the preliminary functional test of the pistons. Also we reported about technical advantages/disadvantages and cost effectiveness of each of the two approaches as well as of the potential piston materials for each approach for future to fully meet the target properties for the piston made of alternative/advanced materials.

An assay of the presence of serpentine minerals in some samples from dust and isolation materials taken at a cement-asbestos factory is presented in this paper. Also is presented a different methodology which was used for this purpose.

Physico-chemical investigations were carried out for limestone samples at different localities in the Republic of Macedonia: mine for nonmetals "Ograiden", Strumica (sample-granulation below: 4, 10,20,32,40, 63 and 90 ~m), A.D. "Mikrogranulat", Gostivar, mine "Banjani" -Skopje, mine "Toplica" near Demir Hisar and from the separation of GP Mavrovo, Skopje, located near Pletvar. Investigation of samples from the previously mentioned localities were carried out using different methods: volumetry, gravimetry, UV-VIS and infrared spectroscopy, as well as atomic absorption and X-ray fluorescence spectrometry, X-ray diffraction and flame photometry. The obtained results lead to the conclusion that all granulometric classes of the limestone samples from "OgraMen", Strumica, are of the best quality.

Among the rich ore deposits present in Macedonia, the sulfide minerals are being the mostly exploited ones. Some of these minerals appear as well formed single crystal species in the nature, but often some other mineral forms accompany them. The difficulties connected with the selection. separation, purification, identification and characterization of several sulfide minerals (galena. PbS; sphalerite/wurtzite (Zn.Fe)S; pyrite, FeS2; chalcopyrite, CuFeS2) from various localities (Sasa, Bucim, Zletovo, Toranica) were discussed. Identification was based on the comparison of our results (obtained by use of the infrared and Raman vibrational spectroscopy and powder X-ray diffraction) with the corresponding literature data for the analogous mineral species originating all over the world.

The most frequently used techniques for mineral detection, identification, discrimination as well as their quantitative determination developed during the last few decades are X-ray diffraction, thermal analysis, optical diffuse reflectance, Raman and infrared vibrational spectroscopy. Since all these techniques have their own advantages and imperfections, in general, it is strongly recommendable (especially in the case of mineral characterization) to use them complementary rather than competitive. Often, however, it is advantageous to use or to develop simple and rapid methods for mineral discrimination as well as for detection of their impurities in mineral mixtures using only one of the above mentioned techniques. X-ray powder diffraction and FT infrared spectroscopy fulfill the above requirements providing the results quickly and giving a very rapid indication about the presence of the existing impurities. In that sense, as a part of a broader study of the structural and spectroscopic characteristics of the minerals originating from Macedonia, we studied the analytical application of the FT IR spectra as well as X-ray diffraction patterns of some carbonate minerals. Here we present comparatively the use of the powder X-ray diffraction and FT IR spectroscopy to distinguish among the geologically important carbonate minerals calcite and aragonite as well as to detect and determine mineral impurities in their mixtures. It was shown that the limit of detection of calcite in aragonite and vice versa using the FT IR spectroscopy is around 2 % impurities, whereas the presence of even lower than 0.5 % impurities of calcite in aragonite can be detected by powder X-ray diffraction.

The Fourier transform infrared (FfIR) and Raman spectra of gypsum (CaS04'2H20) and barite (BaS04) from various localities in Macedonia were studied. Contrary to the group-theoretical predictions, it was found that the band originating from the V2 sulfate mode (expected at around 450 cm-I) does not appear in the infra­ red spectra of either gypsum or barite, apparently due to the high effective symmetry of the force field for this mode. The infrared and Raman spectra of natural gypsum and its synthetic analogue are very similar. On the other hand, slight frequency differences (especially pronounced in the region of the V3 sulfate modes) were registered in the infra­ red spectrum (and, to a considerably lesser extent in the Raman spectrum as well) of synthetic BaS0 4 when compared to the spectrum of mineral barite. Also studied were the FTIR and Raman spectra of a mineral previously character­ ized as anhydrite. Although its morphological characteristics (shape, color and transparency) were quite different from those of gypsum it was shown that the studied mineral is in fact gypsum.

The results from the examination of the presence of serpentine minerals in some geochemical media (air and soil) from the border cross Blace are presented in this paper. The presence of the serpentine mineral of chrysotile type in samples of air and oil is unambiguously shown.

The study of powder X-ray diagrams of calcite and aragonite has shown that the appearance of a rather intense diffraction maximum at 2theta = 27.620 ^o in the aragonite debyegram (absent in the calcite diagram) as well as the existence of an extremely strong maximum at 2theta = 31.970 ^o in the calcite diagram where aragonite does not exhibit diffraction) make it possible to detect impurities of aragonite in calcite and vice versa. The comparison of the data estima-ted by both FT IR and powder X-ray diffraction methods has shown that the X-ray diffraction method is more sensitive.

As a part of the broader research of the structural and spectroscopic characteristics of metal minerals originating from Macedonia we report the results of the analytical application of the FT IR spectra and the powder XRD patterns of the carbonate minerals calcite (CaCO_3), siderite (FeCO_3) and aragonite (CaCO_3). As is known calcite and siderite crystallize in the hexagonal system, while aragonite is orthorhombic. The local symmetry of the CO_3^2^- ions in the structure of calcite type is D_3 and in aragonite is C_s. The lower local symmetry of the CO_3^2^- ions in the latter case causes the appearance (around 1084 cm^-^1) of the v_1 mode in its IR spectrum. Since carbonate minerals, especially the polymorphic forms of calcite and aragonite, may appear in common minerals, it is advantageous to have a rapid and simple method for detecting impurities of these minerals in one another. The appearance of the 1084 cm^-^1 band in the spectrum of aragonite (absent in the spectrum of calcite) enabled us to detect the presence of aragonite in calcite whereas the higher frequency of the v_4 mode in the spectrum of calcite (733 cm^-^1) than in aragonite (712 cm^-^1) made it possible to use their infrared spectra for detecting impurities of calcite in aragonite. The powder X-ray diagrams of these minerals were also examined with the same goal in mind. The symmetry-caused similarity between the infrared spectra of calcite and siderite made impossible their use for detecting of the presence of calcite in aragonite and vice versa and only their XRD patterns could be used.

The appearance of the VI mode (1083 em-I) in the Ff IR spectrum of aragonite (absent in the spectrum of calcite) as well as the lower frequency of the V4 mode in the spectrum of aragonite (713 and 700 em-I) than in that of calcite (732 em-I) made it possible to detect the presence of aragonite in calcite and to determine its content. Similarly, the higher frequency of the V4 mode in the spectrum of calcite (732 em-I) than in aragonite (713 and 700 em-I) was used to detect impurities as well as to determine the content of calcite in aragonite.