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The low temperature behavior of the KTaO3 type incipient ferroelectric crystals is of constant interest. The quantum fluctuations reduce the transition to the ferroelectric state in these crystals. It is possible that the small amount of the dopant Li can lead, through the elastic interactions, to local glass-like short-range order or even to the relaxor ferroelectric order for x > 2.6%. We presented that the low lithium doped x = 0.005 KTaO3 crystals exhibit the dielectric dispersion of e′ and e′′, suggesting the glass-like behavior in the low temperature range.

A systematic approach to the characterization of selenized yeast supplements in terms of the speciation of selenium was developed. The optimized fractionation procedures included the sequential leaching of water soluble, cell-wall bound, and membrane-protein selenium followed by a further fractionation of each extract by high-resolution size-exclusion chromatography. The stability of fractions collected as chromatographic peaks was investigated in the presence of a proteolytic enzyme (pronase XIV) and trypsin in order to discriminate between selenium-containing peptides and other selenocompounds. Reversed-phase HPLC of tryptic digests of size-exclusion chromatographic fractions allowed the identification of selenopeptides by MALDI and electrospray MS. The complexity of the speciation of the water-soluble selenium in yeast was confirmed. Surprisingly, selenomethionine in the water insoluble fraction was found to be bound physically to cell wall constituents rather than being incorporated chemically into the protein structure, in contrast to former studies.

Advances in analytical methodology for speciation of selenium in selenized-yeast food supplements were discussed on the basis of the recent developments in the authors’ laboratory. Particular attention was given to the sample preparation with regard to the fractionation of selenium into different classes of chemical species, the high resolution fractionation of selenium from yeast water extracts by size-exclusion chromatography and characterization of the water soluble protein fraction by combined matrix-assisted laser desorption ionization (MALDI)-time-of-flight mass spectrometry (TOF MS) and electrospray quadrupole-TOF tandem MS. The true speciation of protein-incorporated selenium (down to individual proteins characterized by a unique aminoacid sequence) was discussed using an example of a family of selenium-containing proteins formed in yeast by the substitution of methionine residues by selenomethionine in a salt stress-induced protein.

Starting from the sampling up to the time of analysis, the content of water sample can be altered due to the chemical, physical, and biological reactions it undergoes. This article deals with the processes occurring in the water samples during their storage and with reasons of their occurrence. Special attention has been paid to the chemical and physicochemical reactions as well as to microbiological and photochemical degradation of the component of the sample. Techniques for the water sample preservation are also reviewed.

Paper presents the analysis of shrinkage development in selfconsolidating concretes (SCC). Concretes were cured for 28 day in an insulated environment. The shrinkage was tested on 35x150x1150 mm samples. The specimen had the same volume as ring specimen proposed in the ASTM method of testing the susceptibility of concretes to cracking caused by the restricted radial shrinkage. Linear deformation of concrete samples was measured in constant periods of 500 s using dial gauges with digital data loggers. Conducted tests showed the influence of w/c ratio of 0.28, 0.34, 0.42 and aggregate composition on the development of the autogenous shrinkage in self-consolidating concretes. Additionally, rheological properties of the concrete mixes were tested and compressive and splitting strength was determined. Conducted research allowed to evaluate the influence of w/c ratio and natural aggregate composition on the development of autogenous shrinkage in different stages of curing of SCC.

Zrównoważony rozwój obszarów wiejskich powinien opierać się na wielofunkcyjności oraz wykorzystaniu różnych walorów wsi, w tym również tych naturalnych. Przyrodniczo cenne obszary objęte programami ochrony, takimi jak Natura 2000, bardzo często postrzegane są jednak jako bariery, a nie czynniki potencjalnie wspierające rozwój. W ostatnich latach wokół obszarów Natura 2000 narosło wiele konfliktów, utrudniających nie tylko realizację zadań ochronnych, lecz także wykorzystanie możliwości, jakie ten program stwarza dla rozwoju lokalnego. Niniejsza praca przedstawia wyniki badań nad poziomem akceptacji i opinii kluczowych grup interesariuszy oraz problemami związanymi z funkcjonowaniem programu Natura 2000 podczas przygotowywania planów zadań ochronnych. Badania przeprowadzono wśród 350 uczestników jednodniowych szkoleń nt. programu Natura 2000 przeprowadzonych we wszystkich województwach w Polsce w okresie od stycznia do marca 2013 roku. Wyniki wskazują, iż pomimo dostrzegania przez respondentów wykorzystania Natury 2000 jako atutu w rozwoju lokalnym (głównie w sektorze turystycznym), to wciąż bariery inwestycyjne są główną przyczyną obaw i negatywnych opinii na jej temat. Ankietowani widzą także zdecydowaną potrzebę zaangażowania szerszego niż dotychczas spektrum interesariuszy w proces zarządzania takimi obszarami i pogłębienia dialogu pomiędzy nimi. Aby zarządzanie obszarami Natura 2000 szło w parze z rozwojem obszarów wiejskich, potrzebne jest rzeczywiste przyswojenie wiedzy o programie oraz zaangażowanie samorządów gminnych i innych interesariuszy w przygotowanie planów zadań ochronnych, a także realne wsparcie grup ponoszących koszty programu.

Analyses and results of tests on heat of hydration and compressive strength of high-performance concrete cured in variable thermal conditions are presented in this paper. Investigations of hydration heat of cement were carried out in calorimeter, in adiabatic conditions. Test samples for strength tests were stored in isothermal conditions at temperature of T=8°C, 20°C, 35°C, and in adiabatic conditions at the temperature controlled by the temperature of the sample used in the hydration heat test. The purpose of the research was to determine a relation between the amount and kinetics of heat generation and the early age compressive strength of high-performance concrete cured in the massive structure, where the temperature in concrete changes continuously. The results for high-performance concrete are compared with respective values obtained for normal concrete.

The Fibre Reinforced Polymer (FRP) composite rebar has been used in civil engineering structures for several years. It has many characteristics, which not only are equal to those of steel rebar, but significantly surpass them. The composite rebar has high corrosion resistance, electromagnetic neutrality and has much higher tensile strength than steel. Also, because of its low weight and easy processing composite rebar is convenient for shipment and use. Development of architectural concrete technology in past years opens new, interesting perspectives for use of composite rebar. However, implementation of those concretes in structures is often burdened with many issues, especially concerning faulty performance. One of it is rebar's corrosion, visible on the surface of the element as rusty stains. Even if the structure was properly developed meeting all the requirements for texture, porosity or colour uniformity, and rusty stains can completely destroy the final decorative effect of concrete's surface. Despite many advantages, the use of composite rebar in reinforced structures creates significant number of new "behaviours" in its different working stages. Structures reinforced with the steel rebar will behave differently than the ones with composite FRP rebar under continuous load, in case of a fire, exposed to aggressive environment or at breaking point. In the latter, significant role plays its linear-elastic behaviour in the whole tensile range till rupture. This means that the FPR rebar does not exhibit plastic deformation and reaches its bearing capacity suddenly without any visible signs. This should be considered during designing stage and included as an additional reduction coefficient. The article presents result of research and analysis of destructive tests performed on concrete beams reinforced with traditional steel rebar and composite rebar made of glass fibre and braided with basaltic (GFRP). Four single-span simply supported beams under static load were tested. Both types of beams were designed to have the same bearing capacity. Beams reinforced with GFRP rebar exhibited much bigger cracking than traditionally reinforced bars. The width of cracks appearing in beams reinforced with GFRP bars was equal or greater than limit values (0.4 mm) even though the ratio of moment of resistance and cracking moment was greater than 3. The composite rebar exhibits many significant advantages over steel rebar, but its rather low Young's modulus comparing to steel causes exceeded deflection and cracking of bended concrete elements.

Experimental studies were conducted to investigate the photodegradation of diazepam and sertraline, two of the most frequently used psychiatric drugs, induced by xenon lamp irradiation, which overlap the sunlight spectra, and natural sunlight. Degradation kinetics was established indicating the occurrence of autocatalytic reactions. The application of liquid chromatography coupled to quadrupole time-of-flight mass spectrometry allowed for accurate mass measurements and proper fragmentation of target compounds enabling structure elucidation of various photoproducts of diazepam and sertraline formed during the forced photolysis. As a result, phototransformation pathways were proposed including the compounds and routes of degradation described here for the first time. In the final step, the presence of parent and identified compounds was examined in various environmental water samples. Although, the analytes were non-detected it was assumed that they may undergo different process in the environment such as adsorption, dilution, advection or rapid photodegradation of all compounds.

A series of polycyclic aromatic hydrocarbons (PAHs) of different size and shape has been used to characterize the chromatographic behavior of five calix[4]arene stationary phases in 1,3-alternate conformation synthesized in our laboratory. The selection of linear, four-ring nonlinear, and five-ring PAHs gave data on selectivity changes across range of the calix[4]arene columns. Retention of the 12 aromatic solutes has been evaluated at various methanol contents in the mobile phase (70-100% v/v) and column temperatures (20-45°C). The thermodynamic parameters underlying the retention mechanisms revealed that each of the five calix[4]arene columns exhibited variation in selectivity and retention of PAHs caused by enthalpy and entropy effects. The calixarene stationary phases substituted with electron-withdrawing groups exhibit enhanced selectivity toward PAHs in comparison to the rest of the investigated columns. The observed divergences are due to differences in solute-stationary phase interactions and originate in π-π and π-electron transfer specific to the analytes and the type of calix[4]arene functionalization at the upper rim, as well as steric and sorption phenomena.

Natural organic dyes can be found in many objects of cultural heritage. Identification of coloring substances present in historical paints provides relevant information for a wide range of specialists involved in art science. Determination of the composition of paints allows application of appropriate procedures for restoration and conservation of historical works of art. This information enables treatment in accordance with the ideological and esthetic decisions of the authors. The complexity of the chemical composition of art paints, which, apart from organic dyes can also include inorganic pigments, binders and other additives, hinders isolation and identification of its individual components. Nowadays, there are several analytical techniques and methods for extraction and identification of organic dyes, each of them has its limitations, however. For that reason, the development of the universal methodology for the analysis of colorant composition in art paints remains a challenge for chemists. In present work, an analytical protocol for identification of yellow dyes using reversed phase liquid chromatographymass spectrometry with atmospheric pressure electrospray ionization (LC-ESI/ /MS) is presented. The developed method was successfully applied to identification of the main components of Indian Yellow, weld ( Reseda luteola L.), buckthorn berries ( Rhamnus ) and madder lake (madder plant’s root) extracts, in the historical oil paints from tubes of Richard Aines company, formerly Mulard, owned before him by recognizable French art materials supplier Eduard. The recognition of paints composition was broadened by identification of non organic compounds – carriers of the dye: aluminum hydroxide, tin chloride, chalk, as well as filler like silica and or lead white. Researched samples of painting materials belonged to 19th century famous Polish painter Jan Matejko (1839–1893) and will be very helpful in understanding paintings of him and of his contemporaries.

This paper presents a part of the results from a broader study dealing properties of lightweight self-consolidating concrete. Various self-consolidating mixtures were considered by replacing a part of fine and coarse aggregate with light-weight aggregate. The workability of SCC was evaluated using the slump flow test, V-fimnel test and J-ring test. For verification of concrete segregation the concrete specimens were cutting and a visual evaluated of the distribution of coarse aggregates. Free shrinkage of concrete has been investigated using beam specimens 50 × 50 × 250 mm on Graf-Kaufman test. Restrained shrinkage cracking performance was tested using ring specimens (ASTM CI581), which had an inner steel ring instrumented with an electrical strain gauge to monitor stress rise in the concrete due to drying shrinkage under restrained conditions.

A novel 1,3-alternate 25,27-bis-[cyanopropyloxy]-26,28-bis-[3-propyloxy]-calix[4]arene-bonded silica gel stationary phase (CalixPrCN) was prepared and its structure was confirmed by ATR-FTIR spectroscopy and elemental analysis. The CalixPrCN phase was characterized in terms of its surface coverage, hydrophobic selectivity, aromatic selectivity, shape selectivity, hydrogen bonding capacity, residue metal content, and silanol activity based on Tanaka, Lindner, and SMR 870 test protocols. The effect of the acetonitrile content on the retention and selectivity of the selected neutral, basic, and acidic solutes was studied. The neutral and acidic analytes exhibited classical RP behavior, in which retention time decreases with increasing acetonitrile content. In contrast, basic analytes showed an increase in retention at low and high percentages of acetonitrile, forming "U-shaped" retention profiles. The new calixarene phase was compared with previously reported 1,3-alternate 25,27-bis-[propyloxy]-26,28-bis-[3-propyloxy]-calix[4]arene stationary phase and commercial cyanopropyl column. The results indicate that the CalixPrCN stationary phase behaves like RP packing; however, inclusion complex formation, dipole-dipole, and π-π interactions seem to be involved in the separation process. The selectivity of this phase was demonstrated in separation of polynuclear aromatic hydrocarbons, non-steroidal anti-inflammatory drugs, and sulfonamides as analytes.

The dynamics of Li+ dipoles distributed in the quantum paraelectric matrix of potassium tantalate is investigated via linear and nonlinear dielectric response. It is found that the highly diluted solid solution K0.995Li0.005TaO3, KLT(005), reveals nearly ideal Debye-type dipolar relaxation with conventional frequency dispersion at intermediate temperatures, 30

Zero-field heating (ZFH) susceptibility after zero-field cooling (ZFC) and field cooling (FC) of highly diluted single crystalline sample of K0.995Li0.005TaO3, KLT(005) was measured in order to check, if such composition undergoes a collective dipolar glassy freezing. The results are compared with that obtained for the typical glassy system K0.989Li0.011TaO3, KLT(011). It is concluded that the highly dilute KLT(005) compound does not bear convincing features typical of collective dipolar glassy freezing. It is proposed that the low-temperature state of KLT(005) may be considered as a quantum superparaelectric one that may be toggled into an improper ferroelectric while applying an electric field.

Twelve calix[4]arene stationary phases in 1,3-alternate conformation, synthesized in the authors' laboratory, were characterized in terms of their surface coverage, hydrophobic selectivity, aromatic selectivity, shape selectivity, hydrogen bonding capacity and ion-exchange capacity. The set of tests commonly used for evaluation of commercially available stationary phases was applied to assess fundamental chromatographic properties of the calixarene phases. The new calixarene phases were compared to each other, to Caltrex and LiChrosorb C-18 columns. Principal component analysis has been used to provide comparison between 1,3-alternate calix[4]arene phases and commercially available phenyl, fluorophenyl and fluoroalkyl columns.

Self-compacting concrete can by made in various ways. The optimum mixtures are sensitive with regard to characteristics of components, such as type of the cement, type and amount of superplasticizer, type of sand and fillers. The fabrication of self-compacting concrete requires a more rigorous quality control of materials and selection of the mixture at all stages of mixing and casting. The objective of this paper is to present the effect of additions and admixtures on performance of the self-compacting concrete. The tests confirmed the importance of the quantity of superplasticizers and of compatibility between cement and superplasticizer.

Host–guest interactions can be the unique method of spin manipulation in nanoscale. Strong changes in spin localization are generated when potential barriers between nanographitic units of activated carbon fibers are modified by interaction with adsorbed molecules. Stronger modifications occur when dipolar guest molecules are stimulated with external electric field. We report experimental results which show the influence of electric field on the spin localization in activated carbon fibers.