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Apatites are one of the most intensively studied materials for possible biomedical applications. New perspectives of possible application of apatites correspond with the development of nanomaterials and nanocompounds. Here, an effort to systematize different kinds of human bioapatites forming bones, dentin, and enamel was undertaken. The precursors of bioapatites and hydroxyapatite were also considered. The rigorous consideration of compositions and stoichiometry of bioapatites allowed us to establish an order in their mutual sequence. The chemical reactions describing potential transformations of biomaterials from octacalcium phosphate into hydroxyapatite via all intermediate stages were postulated. Regardless of whether the reactions occur in reality, all apatite biomaterials behave as if they participate in them. To conserve the charge, additional free charges were introduced, with an assumed meaning to be joined with the defects. The distribution of defects was coupled with the values of crystallographic parameters “a” and “c”. The energetic balances of bioapatite transformations were calculated. The apatite biomaterials are surprisingly regular structures with non-integer stoichiometric coefficients. The results presented here will be helpful for the further design and development of nanomaterials.

The chemical composition and structure of bamboo octocoral Keratoisis spp. skeletons were investigated by using: Scanning Electron Microscopy SEM, Raman Microscopy, X-ray Diffraction XRD, Laser Ablation–Inductively Coupled Plasma LA-ICP, and amino acid analyzers. Elements discovered in the nodes (mainly organic parts of the skeleton) of bamboo corals showed a very interesting arrangement in the growth ring areas, most probably enabling the application of bamboo corals as palaeochronometers and palaeothermometers. LA-ICP results showed that these gorgonian corals had an unusually large content of bromine, larger than any other organism yet studied. The local concentration of bromine in the organic part of the growth rings of one of the studied corals grew up to 29,000 ppm of bromine. That is over 440 times more than is contained in marine water and 35 times more than Murex contains, the species which was used to make Tyrian purple in ancient times. The organic matter of corals is called gorgonin, the specific substance that both from the XRD and Raman studies seem to be very similar to the reptile and bird keratins and less similar to the mammalian keratins. The missing cross-linking by S-S bridges, absence of aromatic rings, and significant participation of β-turn organization of peptides differs gorgonin from keratins. Perhaps, the gorgonin belongs to the affined but still different substances concerning reptile and bird keratin and in relation to the more advanced version—the mammalian one. Chemical components of bamboo corals seem to have great medical potential, with the internodes as material substituting the hard tissues and the nodes as the components of medicines.

Due to the increasing of the price of different materials and resource saving it is very promising to develop technology of creation cheap coatings with specified properties. We developed a diffusion-doped powder based on austenitic steels for producing plasma-sprayed coatings. In comparison with Ni-based powders our materials have better adhesion, they are cheaper, they have better mechanical machinability, it is possible to produce coatings with required properties. In our work, the features of diffusion doping of microparticles of powder, the behavior of the powder in the plasma jet were studied. The significant decreasing of porosity, increasing of adhesion of the plasma-sprayed coatings after laser processing were marked. The substantial increase of wear-resistance in 2,5-3,0 times in comparison with untreated coatings when working in conditions of abrasive wear and atmospheric precipitation was revealed.

A series of linear profiles of the elements of the enamel in human molar teeth were made with the use of an electron microprobe and a Raman microscope. It is postulated that the enamel can be treated as the superposition of variable &ldquo, overbuilt&rdquo, enamel on the stable &ldquo, core&rdquo, enamel at the macro-, micro- and nanoscale level. The excessive values characterize the &ldquo, overbuilt enamel&rdquo, All the profiles of excessive parameters along the enamel thickness from the enamel surface to the dentin enamel junction (DEJ) can be approximated very precisely with the use of exponential functions, where Ca, P, Cl and F spatial profiles are decaying while Mg, Na, K and CO32&minus, ones are growing distributions. The &ldquo, apatite formed on the boundary with DEJ, enriched in Na, Mg, OH and carbonates, reacts continuously with Ca, Cl and F, passing into an acid-resistant form of the &ldquo, enamel. The apparent phases arriving in boundary regions of the &ldquo, were proposed. Microdiffraction measurements reveal relative variation of energy levels during enamel transformations. Our investigations are the milestones for a further new class of biomaterial and nanomaterial development for biomedical applications.

New types of biological apatites have been discovered in molar sheep and horse teeth and are divided in two types. In the first and more general type, the release of Mg ions is parallel to the changes in composition of apatite leading to a final stoichiometric ratio of Ca to P ions, going from dentin depth towards the boundary of enamel with air. Inside dentin, another apatite sub-types were discovered with alternating layers of Mg-rich and C-rich apatites. The approximate formal stoichiometric relationships for these peculiar types of bioapatites are suggested. We identified two kinds of ion-exchanges responsible for formation of peculiar apatites. Various combinations of main and minor elements lead to new versions of biological apatites.

The dentin-enamel junction (DEJ) is known for its special role in teeth. Several techniques were applied for the investigation of the DEJ in human sound molar teeth. The electron (EPMA) and proton (PIXE) microprobes gave consistent indications about the variability of elemental concentrations on this boundary. The locally increased and oscillating concentrations of Mg and Na were observed in the junction, in the layer adhering to the enamel and covering roughly half of the DEJ width. The chemical results were compared with the optical profiles of the junction. Our chemical and optical results were next compared with the micromechanical results (hardness, elastic modulus, friction coefficient) available in the world literature. A strong correlation of both result sets was proven, which testifies to the self-affinity of the junction structures for different locations and even for different kinds of teeth and techniques applied for studies. Energetic changes in tooth strictly connected with crystallographic transformations were calculated, and the minimum energetic status was discovered for DEJ zone. Modeling of both walls of the DEJ from optical data was demonstrated. Comparing the DEJ in human teeth with the same structure found in dinosaur, shark, and alligator teeth evidences the universality of dentin enamel junction in animal world. The paper makes a contribution to better understanding the joining of the different hard tissues.

Fossilized wood belongs to the most exciting, however, rarely studied objects in nature. Several kinds of petrified wood with different combinations of minerals have been studied: apatite – calcite; calcite – pyrite; hematite – gypsum wood; quartz - goethite; goethite – calcite woods, from different countries and estimated as old in the time range of 1.8–306 MA. The samples cover nearly the whole time of tree existence on the Earth. The application of synchrotron radiation for X-ray microdiffraction analysis of petrified wood is presented and compared to elemental (electron microprobe) and molecular (micro Raman) analyses with the use of table-top instruments. The analysis of preserved cells permineralized with two minerals allows tracing both the structure of cell walls and the remains of ancient organic matter. Lignin is most often met among the remains of the primary organic matter and is clearly observed in all kinds of wood, except the apatite-calcite one. The Eh-pH diagrams tailored to each combination of minerals with organic matter allow to estimate the original conditions of mineralization and give the indications for the potential biomimetic synthesis.

Agaricus bisporus fruiting bodies were subjected to processing: blanching, boiling in water and blanching followed by lactic acid fermentation. Water soluble polysaccharides were obtained from fruiting bodies, quantified and analysed in terms of chemical composition, antioxidant capacity and antiproliferative activity towards cancer cell lines (MCF‐7 and T‐47D). The content of water soluble polysaccharides ranged from 7.35 ± 0.12 to 6.90 ± 0.17 mg g⁻¹ fresh weight of sample. Boiling in water and blanching followed by fermenting caused minor decrease in the content. Fourier Transform Infrared spectroscopy of the extracted polysaccharides showed that both α‐ and β‐linkages are present in the samples. Size exclusion chromatography confirmed the presence of 163.3 and 1.9 kDa molecules. The processing caused changes in chemical composition (protein and phenolics content decreased). The isolated polysaccharides exerted antioxidant and antiproliferative activities. Both the activities were slightly lowered as the result of the processing.

In this paper authors overviewed the most important stages of ceramics production process which give significant influence on final properties of product. Often density and porosity on the all producing stages determines exploitation ceramics properties. A calculation method for fractions ratio selection which provides optimal density is suggested here. Also, density changes during operations of grinding, forming, thermal treatment and sintering a row of specimens are researched and analysed. The data received allow to predict semi products size behaviour while producing and get definite final part with dimension required.

Water soluble polysaccharides (WSP) were isolated from processed and non-processed fruiting bodies of oyster mushroom ( Pleurotus ostreatus ). The processing methods involved: blanching, boiling and blanching followed by fermenting with a strain of lactic acid bacteria ( Lactobacillus plantarum ). The yields of WSP ranged from 78.7 ± 1.5 mg/g to 120.1 ± 4.9 mg/g dry weight of sample. Blanching did not affect the content of WSP. Boiling for 15 min, led to the substantial decrease in the amount of WSP (34.7% decline). The isolated samples differed in carbohydrate, protein and phenolics content. FTIR spectroscopy of the WSP samples confirmed the presence of both α- and β-glycosidic linkages. Gel permeation chromatography showed the presence of compounds having the molecular weight of 198.3, 11.9, 3.1 kDa. The samples possessed antioxidant capacity measured by ABTS method (14.14 ± 0.63 to 29.48 ± 1.12 μmoles of Trolox per 1 g dw) and FRAP assay (2.49 ± 0.54 to 16.52 ± 0.55 μmoles of Trolox equivalents per 1 g dw). The antioxidant potential was decreased by the processing. Similarly, antiproliferative activity of WSP towards human breast cell lines (MCF-7 and T-47D) was lower due to the processing.

Water soluble polysaccharides (WSP) were isolated from Lentinus edodes fruiting bodies. The mushrooms were previously subjected to various processing techniques which included blanching, boiling, and fermenting with lactic acid bacteria. Therefore, the impact of processing on the content and biological activities of WSP was established. Non-processed fruiting bodies contained 10.70 &plusmn, 0.09 mg/g fw. Boiling caused ~12% decrease in the amount of WSP, while blanched and fermented mushrooms showed ~6% decline. Fourier transform infrared spectroscopy analysis (FTIR) confirmed the presence of &beta, glycosidic links, whereas due to size exclusion chromatography 216 kDa and 11 kDa molecules were detected. WSP exhibited antioxidant potential in FRAP (ferric ion reducing antioxidant power) and ABTS (2,2&prime, azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) assays. Cytotoxic properties were determined on MCF-7 and T47D human breast cell lines using MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) test. Both biological activities decreased as the result of boiling and fermenting.

Recently it has been shown that very deep lesions, extending through the enamel into the dentin, can still be remineralized when brought into contact with a mineralizing agent. Biodentine is a calcium silicate based dentin substitute recommended to use in dentistry for direct and indirect pulp capping, perforations, apexification and retrograde root filling. The aim of the study was to examine the reaction between Biodentine and dentin comparing chemical composition of both of them in microspectral analysis. The human molars dentinal samples with Biodentine were analyzed by scanning electron microscopy (SEM) and electron probe microanalyser (EDS) with image observation function. Aditionally Raman microscope was used to identify Biodentine/denine interface. The results showed that Biodentine released some of its components into dentin specimens and caused the uptake of Ca and Si in the adjacent dentine. The formation of an interfacial layer at the Biodentine/dentin border was identified as a “Transition Zone”. On the basis of performed experiment it can be concluded that Biodentine is an active dental material and microanalytic methods used in the study are suitable to investigate it. The obtained outcomes can open up possibilities for a non-operative approach to deep caries cavities.

The aim of a recent paper was to recognize the chemical and structural changes in apatites, which form both the enamel and the dentin of the human tooth. The aim was achieved by scrutinizing the linear elemental profiles along the cross-sections of human molar teeth. Essentially, the task was accomplished with the application of the Electron Probe Microanalysis method and with some additional studies by Micro-Raman spectrometry. All the trends in linear profiles were strictly determined. In the enamel zone they were either increasing or decreasing curves of exponential character. The direction of the investigations was to start with the tooth surface and move towards the dentin–enamel junction (DEJ). The results of the elemental studies were more visible when the detected material was divided, in an arbitrary way, into the prevailing “core” enamel (∼93.5% of the total mass) and the remaining “overbuilt” enamel. The material in the “core” enamel was fully stable, with clearly determined chemical and mechanical features. However, the case was totally different in the “overbuilt enamel”, with dynamic changes in the composition. In the “overbuilt” layer Ca, P, Cl and F profiles present the decaying distribution curves, whereas Mg, Na, K and CO32− present the growing ones. Close to the surface of the tooth the mixture of hydroxy-, chlor- and fluor-apatite is formed, which is much more resistant than the rest of the enamel. On passing towards the DEJ, the apatite is enriched with Na, Mg and CO32−. In this location, three of six phosphate groups were substituted with carbonate groups. Simultaneously, Mg is associated with the hydroxyl groups around the hexad axis. In this way, the mechanisms of exchange reactions were established. The crystallographic structures were proposed for new phases located close to DEJ. In the dentin zone, the variability of elemental profiles looks different, with the most characteristic changes occurring in Mg and Na concentrations. Mg content increases more and more when passing deeper in the dentin, while Na content decreases along this route. Na concentration reaches its maximum when it is very close to the DEJ zone. But the carbonate and phosphate spatial distributions inside the dentin refute the potential conclusions drawn from the studies of Mg and Na profiles.

Wavelength-dispersive X-ray fluorescence can be characterized by its advantages and drawbacks. Unbeaten spectral resolution in a range below 5 keV, good operational stability, excellent ability of making averaged analysis, and good presentation of peak shape which gives the basis for the chemical speciation are the advantages. Among the drawbacks, the following are important: system with sequential analysis of particular elements, low output of energy supplied to the device, and great cost of instrument which can be amortized only in routine operations. In routine geological and environmental analyses, the WD-XRF performs better than other simpler instrumental or wet techniques. WD-XRF is continuously improved, by applying new multilayer interference mirrors (MIM) for detection and quantification of very light elements. Bad spectral resolution of MIM noted earlier is now improved by tailoring their shape to the shape of gratings. The progress in the long wavelength spectral region joined with efficient and precise wavelength resolution systems enables the application of WD-XRF for speciation analysis. In another effort, XRF spectrometry is treated as a tool for obtaining quantitative basis for the judgement on Linnaean systematic classification of plants and opens the field to a new discipline – quantitative biology.

The bone fragments of the Australopithecus Africanus from the dolomitic cave in the Cradle of Humankind in South Africa have been studied by the use of several spectral techniques. The aim was to establish their degree of preservation and possibilities of inferring the life conditions from them. X-ray diffraction studies revealed the transformation of the mineral components partially into fluoroapatite form with addition of goethite, birnessite and quartz phases and with surprisingly well preserved collagen remains. Several important chemical elements were detected by using the electron (EPMA) and synchrotron-based X-ray fluorescence (XRF) microprobes. Among them, Sr and Zn were distributed in a way following the distribution of Ca, the main element of the bones. We suspect the immanent crystallographic substitution of Ca in this case in native bone. Iron followed the distribution of Sr but while Sr is distributed in a continuous way in more rigid locations, iron occurs mainly in the edge zones of the bones and in spot-like inclusions inside. Some part of the spots located in a very edge of bone is also filled with Mn and Cu. It suggests that the porosity and fracture of bones plays a more significant role in the localization of Fe, Mn and Cu. They also form a rigid thin layer (100–250 μm) avoiding further penetration. As (as AsO43−?) distribution pattern is unique and seems to occur in those locations where the concentrations of Sr are small. The conditions for bone penetration as determined from Eh-pH diagrams suggest that is rather impossible to preserve the organic matter in locations of Mn and also that Mn and Fe hardly can meet in the same spots.

Important bioinorganic objects, both living and fossilized are as a rule characterized by a complex microscopic structure. For biological samples, the cell-like and laminar as well as growth ring structures are among most significant. Moreover, these objects belong to a now widely studied category of biominerals with composite, inorganic-organic structure. Such materials are composed of a limited number of inorganic compounds and several natural organic polymers. This apparently simple composition leads to an abnormal variety of constructions significant from the medical (repairs and implants), natural (ecological effectiveness) and material science (biomimetic synthesis) point of view. The analysis of an image obtained in an optical microscope, optionally in a scanning electron microscope is a topographical reference for further investigations. For the characterization of the distribution of chemical elements and compounds in a material, techniques such as X-ray, electronor proton microprobes are applied. Essentially, elemental mappings are collected in this stage. The need for the application of an X-ray diffraction microprobe is obvious and our experience indicates on the necessity of using the synchrotron-based devices due to their better spatial resolution and good X-ray intensity. To examine the presence of the organic compounds, the Raman microprobe measurements are good options. They deliver information about the spatial distribution of functional groups and oscillating fragments of molecules. For the comprehensive investigation of bioinorganic material structural and chemical features, we propose the following sequence of methods: optical imaging, elemental mapping, crystallographic mapping, organic mapping and micromechanical mapping. The examples of such an approach are given for: petrified wood, human teeth, and an ammonite shell.

Dental enamel has been widely studied by particle-induced x-ray emission (PIXE), but less attention was paid to its demineralization, which leads to caries formation. Using broad-beam PIXE and µ-PIXE, we investigated normal enamel and the in vitro formation of pre-carious lesion in lactic acid solution, aiming also to evaluate intercusp differences within the same tooth. Broad-beam PIXE was performed using 3.0 MeV protons, and µ-PIXE maps of Ca, Fe and Zn were collected with 3.1 MeV protons at ∼4 µm resolution. In normal enamel a differentiated Ca-rich surface layer was observed, where Fe and Zn reached their highest levels. In deeper layers, Fe and Zn evidenced quasiperiodic patterns of maxima, possibly due to coupled diffusion-reaction catalytic processes involved in the enamel growth. Both Fe and Zn appeared to be located in a few distinct types of pools. Near the surface, demineralization induced an increase of Fe, Cu, Zn, Sr and Pb with respect to Ca, attributed to partial hydroxyapatite dissolution and/or to chelate extraction and concentration of trace metals. Ca maps revealed limited changes in the surface layer and a massive loss in the inner enamel; here, Fe was almost depleted and Zn partially removed. The maps of Ca, Fe and Zn demonstrated major intercusp variations in both normal and altered enamel. Thus, broad-beam PIXE and µ-PIXE, which do not require (semi)thin sectioning of the tooth as the conventional methods, provide compositional and structural insight of normal dental enamel, of its intercusp variability and of the alterations produced by in vitro demineralization, largely not accessible to the current techniques, and highly relevant for understanding the incipient caries formation. Copyright © 2008 John Wiley & Sons, Ltd.

In our previous contributions [R. Mroczka, G. Żukocinski, A. Kuczumow, J. Alloys Compd. 362 (2004) 88–95; R. Mroczka, G. Żukocinski, A. Kuczumow, Geometrical description of the X-ray capillary and total reflection mirror surfaces with assumed reflection features, J. Alloys Compd. 382 (2004) 311–319], we solved the problem of analytical description of capillaries with designed reflection features. Now, the numerical program for ray tracing simulations was written, fully basing on our original analytical calculation of trajectories. All parameters essential for X-ray capillary optics system, such as point and extended X-ray sources, different ranges of photon energy, geometrical parameters of capillaries, variable surface roughness, different kinds of materials (mainly metals), location of target in relation to capillary, were tested. Profiles of output photon beam on the target were obtained. Here, some results of simulations, such as the influence of the photon energy, the capillary sizes and the internal wall smoothness on the efficiency of propagation were presented. All simulations were helpful in making decisions about the optimal shapes and parameters of capillaries that were manufactured in our laboratory. In the preliminary experimental work, the electrochemical manufacturing of capillaries with the metallic (Cu and Ni) walls was described. The cathode wire was coated with copper layer in controlled electrolytic process. It led to precise formation of the parabolic shape of a core part. Subsequently, a thin layer of nickel was coated in electroless way and electrochemically passivated. Then, a thin copper layer and subsequently, thick nickel one were electroplated, forming the body part of the capillary. The adjustment of the internal walls of the capillaries to the designed shape was controlled with the electron microscope and it was proved that it could be kept within ±1 μm scatter on a distance of several centimeters along the main axis. The roughness (rms) of the internal capillary walls was controlled by the atomic force microscope. The roughness was kept in the range of 3.5–5 nm and was in the low limit of allowed levels. The production will be optimized in the future.

Special kinds of petrified wood of complex structure were investigated. All the samples were composed of at least two different inorganic substances. The original cell structure was preserved in each case. The remnants of the original biological material were detected in some locations, especially in the cell walls. The complex inorganic structure was superimposed on the remnant organic network. The first inorganic component was located in the lumena (l.) of the cells while another one in the walls (w.) of the cells. The investigated arrangements were as follows: calcite (l.)—goethite–hematite (w.)—wood from Dunarobba, Italy; pyrite (l.)—calcite (w.)—wood from Łukow, Poland; goethite (l.)—silica (w.)—wood from Kwaczala, Poland. The inorganic composition was analysed and spatially located by the use of three spectral methods: electron microprobe, X-ray synchrotron-based microprobe, μ-PIXE microprobe. The accurate mappings presenting 2D distribution of the chemical species were presented for each case. Trace elements were detected and correlated with the distribution of the main elements. In addition, the identification of phases was done by the use of μ-Raman and μ-XRD techniques for selected and representative points. The possible mechanisms of the described arrangements are considered. The potential synthesis of similar structures and their possible applications are suggested.

The geometrical description of the capillary systems adjusted for controlled guiding of X-rays is presented. Simple relationships between the reflection angle ϑ , the angle α of the capillary wall inclination with respect to the capillary main axis and the angle γ of the ray inclination in relation to the main axis are proved. Once established, the relationships help in the small angle approximation to derive differential equations describing the constant reflection profile of the capillary wall. Alternatively, the system of algebraic relationships is established. The systems of equations correspond either to the control over reflection angle or to the control over the shape of the wall. The way for calculation of the forces to draw capillaries of desired shape is then demonstrated. Finally, complete relationship between capillary shape and variability of the reflection coefficient is suggested.

The possibilities of examining patterned natural and mineralised biological objects, using X-ray synchrotron facilities, complemented by electron microprobe and optical analysis are reviewed. The objects under investigation include: petrified wood, speleothems, corals, shells of molluscs and remains of belemnites. All those objects have important information embedded in their patterned structure. Using microprobe type devices, one can disentangle the internal structure of the objects and reveal the hidden information. This information can be of great significance to climatic, geological, chronological, and ecological studies and specific examples in each category are shown, taken from our work and compared with the results of other authors where necessary. The added value of the X-ray and electron microprobe measurements in relation to the mass-spectrometric methods is shown for the specific cases. In addition, the results concern materials where organic and even biological material is combined with inorganic matter, like calcite, silica varieties and metal oxides. The investigation of such patterned objects as goethitized wood, composed of goethite, calcite and organic matter should therefore be of interest to materials scientists, synthesizing composite materials.

Rostra (bullet-shaped internal shells) of two species of belemnites: Belemnopsis sp. (from Bathonian Stage sediments ∼161–166 Ma ago) and Hibolites sp. (from Middle Oxfordian sediments ∼154–157 Ma) were investigated by the use of 1B2 microfluorescence beamline in Pohang Light Source in Korea. The cross-sections of the rostra showed an ordered structure of concentric growth laminae cut across by radial calcite crystals. The inner and outer parts of the cross-section differ in the size of calcite crystals, building the block. Very fine crystals existing in the inner parts of rostra are replaced by monocrystals in their external parts. Some compounds of metallic elements such as iron and zinc are present in the calcite matrices of belemnites. Their presence is especially pronounced in the zones separating particular growth rings. The concentrations of elements in calcite matrix were calibrated by atomic absorption method and the results for alkaline elements are: for Sr ∼1000 ppm for Oxfordian specimen and ∼3000 ppm for Bathonian; for Na, ∼2000 and ∼1400 ppm; for K, ∼160 and ∼100 ppm, respectively. The synchrotron-based investigations were complemented with the electron microprobe search for low-Z elements; using this method sodium, potassium, aluminum, silicon, chlorine and sulfur were detected in the matrix. The variability of molar Mg/Ca ratio follows the optical variability of the annual growth zones of the samples, suggesting that this ratio could be used as a palaeothermometer. Possibilities of both application of the elemental data for the estimation of palaeotemperatures, and cross-checking with the isotopic data are discussed. The substantial amounts of the excess carbon were detected in the samples. They are concluded to be potentially useful for the analysis of remnants of original biological matter.

Using the methods of geometrical optics, different cases for allowed X-ray trajectories in single capillaries are studied and it is proved that they cannot be described by the same sets of equations. Three main cases should be considered. In two cases, the test X-rays strike both sides of the capillary upon passing, be the second wall convex or concave. In the third case, called the whispering gallery mode, the path is allowed along the single, external wall of the capillary. This case is realistic for some off-axis, close to the wall, trajectories. A trajectory along the capillary with the curved main axis is the particular case, joining the features of the cases mentioned earlier. The separate consideration of different kinds of trajectories has important implications. The first case corresponds to the ideal trajectory in single capillaries, whereas the second and third describe realistic trajectories in the compound polycapillary systems. The transformation of the polycapillary systems into the coaxial polycylindrical systems is considered. In the third case, which constitutes a transition to trajectories of X-rays on the curved mirror surfaces, the removal of the opposite wall of the capillary can be allowed. Surprisingly, very simple angular relationships lead to the differential equations, describing capillary optics in the terms of geometrical parameters of capillary. The equations describing the surfaces on which the X-rays behave in isoreflective way, i.e. they have the same angle of incidence all along the trajectory, are derived. The proposed approach is widened for modeling of surfaces in order to enable the reflections with continuously changing and controlled reflection angle.

Three representative samples of petrified wood were investigated: wood from King George Island, Antarctica; wood from Bio-Bio province, middle Chile and wood from Łukow, Poland. Microdiffraction measurements of the Chilean and Łukow wood were made at LURE. Chilean and Antarctic samples were permineralised by silica material, but the share of undefined calcium silicates in construction of some intracellular locations in the latter sample was significant. In contrast, the wood from Łukow was replaced by calcite with a small presence of secondary silica. Linear scans were conducted using the X-ray microfluorescence beamlines in synchrotron devices in Orsay, France and Pohang, South Korea. The results were completed by the measurements of light elements with the use of electron microprobe. The list of major and minor constituents of all samples was established. The occurrence of such medium-Z elements as Fe, Zn, Cu and Ni was common in the samples. The samples of Chilean wood were more enriched in trace elements and minor amounts of As, La, Br and Cl were found in addition to the previously mentioned elements. Correlation of the trace element contents with the ring structure of the wood was detected. The annual ring, tissue and even cell details of the original wood were preserved by silica and calcite minerals and could be studied using the elemental mapping technique. Implications of the recent study for the material science are indicated.

A sample of stalagmite from Grotte de Villars, Dordogne, France was analyzed by the use of X-ray synchrotron microprobe in LURE, Orsay, France. Together with the signal of Ca, the main element, much weaker but clear signals of Sr, Fe, Zn and Pb were registered. The X-ray scattered radiation was applied for recognition of the annual zones in the stalagmite structure in parallel with the gray scale morphology from the optical microscope. The elemental scans were superimposed on the optical image of the sample. It was established that places corresponding to dark locations on the annual rings were narrower, composed of less porous matter and had much greater contents of iron and zinc and elevated ratio of Sr/Ca. In the supplementary electron microprobe measurements, the elevated amounts of lighter elements, Si and Mg were found in the same locations. These results will allow a very accurate study of stalagmite elemental composition which is of first importance for paleoclimatic studies from speleothems.

The investigation of the interesting collection of the petrified wood from Bondyrz, Roztocze, south-eastern Poland, has been continued. Two kinds of microprobes such as electron microprobe from the Catholic University of Lublin and synchrotron-based X-ray microprobe from LURE, Orsay, were applied to detect the elements associated with the main component – silica and their spatial distribution and interrelations. The distribution of carbon in the petrified material has been established, which is important since that element is the main remains from the history of the trees. The carbon distribution was characteristic – it concentrated on a place of primordial dark wood. The distribution patterns of the other elements were either similar to that of carbon (Cu, Pb) or they concentrated in separate inclusions (Fe, Al, K, Na, Ca). The replicating mode of the original wood pattern in silica and carbon-containing material was explained. Some indications about the composition of the primordial petrifying solution, the rate of the petrifaction process and the recent coloration of the sample could be concluded from the compositional patterns of silica. The boundary between totally and partially petrified zones could be well observed.

Since the investigations on petrified wood performed so far have not proved the assumption that the ring structure is coupled to the changes in the crystalline form of silica, attention was paid to other possible reasons. Using small angle X-ray scattering methods we determined the Porod curves and pore size distributions for five different samples of petrified wood, of different origin. We observed clear porosity differences in different samples. In addition, the normal X-ray diffractometric measurements were carried out, which gave a totally uniform image of the crystallographic structure of all the samples. All of them were made of pure α-quartz. The differentiation of rings in dark and bright zones should be put down to the changes in porosity rather than to other factors. The pores seem to be much more concentrated in those ring locations, which correspond to the original dark wood positions in living wood.

Pieces of petrified wood from south-eastern Poland comprising one of the greatest European collections were investigated. The age of Miocene wood was estimated at 50 million years. Taxodioxylon sequoianum Gothan. was recognised as the dominating species among the preserved samples. Silica material, basic for the petrifaction processes, was investigated by synchrotron-based microfluorescence and microdiffraction. Different distribution patterns were determined after careful examination of linear scans and elemental maps: calcium, potassium and titanium were uniformly spread in the silica matrix while the iron content was concentrated in clear inclusions; other detected elements, as Cu, Zn, Cr, As were observed mainly in the form of inclusions. There was no difference in microdiffractograms for silica between the places of original dark and light wood. One could find little difference in diffraction patterns of samples with the elevated content of iron. In general, the diffraction patterns of silica from petrified wood could be associated with quartz patterns from 1998 JCPDS-International Centre for Diffraction Data.

An x-ray microprobe was used to perform both linear and area scans of wood material from Polish Pinus silvestris. The investigation revealed variations in behaviour and distribution for different chemical elements. Univalent cations and anions generally show a very irregular distribution in wood which is difficult to associate with any known structural factors. The multivalent element distribution as a rule follows the ring density pattern. Some elements (e.g. iron) show a clear tendency to be included in channel-like structures.

Wavelength-dispersive X-ray fluorescence (WD-XRF) is a recently well-grounded technique, with unbeaten application in some significant fields: metallurgy, geological analysis, and forensic science. Up to now, the method was rather conservative in construction systems and rate of the progress. Wavelength-dispersive X-ray spectrometry is characterized by very good spectral resolution for photon energies below 5 keV; total stability of devices in operations, both repeatable and long-lasting; excellent quantitation; and clear peak shapes enabling chemical speciation. WD-XRF systems operate by sequential elemental analysis. The classical version of method is suffering from very low rate of transforming of supplied energy in the final photons, what has effect on the significant cost of device and operation. Now, the progress is going. New multilayer interference mirrors (MIM) are replacing older multilayers, improving the spectral resolution of the structures mentioned and they are applied for analysis of very light elements. Also recently, the combinations of polycapillary half-lenses, full lenses, or doubly curved crystals (DCCs) enable to overcome the essential drawback of old versions: some new devices became lightweight, with small consumption of energy, with the ability of focusing the exciting beam. All the progress widens the possibility of speciation analyses. New unexpected fields grew, e.g. the trials of quantitative differentiation of species in biology, by the use of multielemental analyses what should complement traditional Linnaean systematics.

An X-ray capillary microprobe was applied to the investigation of Pinus silvestris wood from Polish forests. The micrometre range of the microprobe gave an insight into the wood sub-ring structure. The use of transmitted and scattered radiation permitted the detailed tracing of the subtle changes in the density of the wood. The changes in density were connected with the changes in temperature during the growth period. It was established that some kinds of biological activity in the case of Polish conifers covered the whole year, including winter. Samples of wood from the northern Swedish Picea Abies showed totally different mechanisms of winter behaviour.

"Legal highs" known also as "smarts", "legal drugs" or "boosters" contain in their composition psychoactive substances the production, sale and possession of which are not prohibited in legislation. They are offered for sale under the cover of collectors' items, a salt bath, aroma sticks, or plant fertilizer. Marketing was the reason for such high sales of these "highs" in Poland. The phenomenon became of concern when information became available about the first cases of tragic health consequences. Raising the awareness of youth about the level of imminent danger and serious consequences associated with the use of legal highs may be a very effective way to develop appropriate attitudes of young people, and in the light of their own health can help them take proper life decisions."Legal highs" are substances of natural or synthetic origin having psychostimulating properties. These compounds may differ in chemical structure, potency, half-life, metabolism and severity of side effects. Their pharmacological activity is associated with changes in the neurotransmitter system. After higher doses of "legal highs" psychotic symptoms may occur: visual and auditory hallucinations resembling schizophrenic endogenous psychoses. An alarming fact is the underestimation of the adverse effect of these substances on human health. Any actions aimed at improving this situation are extremely important; therefore, in one of the key projects undertaken at the Institute of Rural Health in Lublin, in cooperation with other scientific institutes, concerned the analysis of a selected series of "legal highs". This research was meant top serve as a source of information for science and medicine, and for popularizing knowledge about legal highs.

Black corals (Cnidaria, Antipatharia) from three different sources were investigated with the aim of detecting inorganic components and their morphology. In general, the skeleton of black corals was composed of the chitin fibrils admixed with peptides and the chitin presence was confirmed by the X-ray diffraction (XRD), Fourier Transformed Infrared Spectrometry (FTIR) and microRaman Microscopy, the latter giving the opportunity of tracing single fibrils and their location. The composition and concentrations of the inorganic components of the black corals were measured, using a scanning electron microprobe and micro-Particle Induced X-ray Emission (μ-PIXE). The application of such instruments enabled the estimation of the constituent distributions in a microscale. The mapping option was the most useful technique of making analyses in these studies, just to reveal the composition of chamber-like cells. Analysis of the morphology and microstructure showed that there were three distinct regions within the coral: a core and the cells encircled with adjacent interface gluing strips. The majority of the elements analyzed were selectively distributed and segregated in a striking way in mentioned distinctive zones of the skeleton and it was detected for the first time. The core area was characterized by the relatively elevated concentrations of Ca. The measurements gave extremely clear images of the distribution of particular elements in the skeletal tissue, with I, Ca, K and Fe much more concentrated in the gluing zones, while C, N, Na and Mg present in the interiors of particular skeletal cells. The distribution of some elements (Mg, Fe) and some compounds (chitin) and functional groups (S-S, C-I) allows differentiating the biological and mechanical functions of particular fragments of the rods. The kinds of elements and their concentrations measured were essentially in compliance with rare data available in the literature. The Raman technique gave the additional qualitative information about the structure of gluing zone and the chitin fibrils and surrounding matrix inside the cell interior. © 2008 Elsevier B.V. All rights reserved.

Cuttlebone exhibiting high compressive strength is a very interesting material from the biomimetic materials' technology point of view. Its microstructure and chemical composition were characterized by complementary analytical techniques. Structural features of the skeleton were revealed by SEM, micro-Raman, FT-IR and XRD measurements. XRD analyses showed that the only mineral phase present in the samples is aragonite. 2D-maps obtained from micro-Raman analyses for peaks attributed to aragonite (1100 cm- 1) and chitin (1660 cm- 1) revealed that the septa are richer in chitin and pillars in aragonite. 2D-distributions of elements detected by a electron microprobe showed that Ca-rich locations are poor in Mg, Na, and Br. Ca is mainly present at those locations where aragonite prevails. Bromine, sodium and magnesium are most likely located in the organic matrix. The average content of the elements, as determined by ICP-OES, was: Na - 1.0%, Mg - 0.133%, K - 0.26%, Fe - 0.03% and Sr - 0.28%. Using the elemental CHN analysis the following amounts of nitrogen, carbon and hydrogen were detected: 1.42%, 15.36% and 0.68%, respectively. The elemental analysis together with TGA measurements allowed evaluating the approximate concentration of organic matter in the cuttlebone at the level of 10%., This research has been partially supported by a Marie Curie Fellowship under contract number: HPMT-CT-2000-00006.

Among all of X-ray capillaries, those produced from metals attract special attention due to their specific advantages: less severe limitations on the value of the critical reflection angle, better control of the capillary shape, the maintenance of the straight main axis. The metallic, single bounce capillaries with gold and rhodium internal surfaces described in this paper are produced according to the original method invented at KUL. The production of the capillaries started from the formation of the internal steel mandrel of a designed shape that was later covered with another metal and finally pressed with the epoxy-resin. Then the mandrel was removed by the combination of mechanical and chemical actions. The shape of capillaries was controlled with the laser scan micrometer. The long-distance shape distortions, obeying so-called waviness correlation length were pointed out. The capillaries produced in our laboratory were characterized by the waviness amplitudes reaching 40–80 nm with correlation length about 300 μm. The symmetry of the opening and the straight shape of the main axis were investigated with the optical microscope and laser light transmitted through the capillary and registered with the CCD camera. The symmetry was found close to circular. The internal surface of the capillary was studied on the longitudinal cross-sections by means of the field emission scanning electron microscope (FESEM) and atomic force microscope (AFM). The surface roughness (rms) was determined, the parameter defining the ability of the surface to reflect X-rays efficiently in the total reflection mode. The best gold surfaces produced up-to-now had the rms ~2 nm, as measured on 1 μm×1 μm areas. The results of preliminary exercises with synchrotron radiation were demonstrated. © 2008 Elsevier B.V. All rights reserved.

A calcite deposit (stalagmite) from the Godarville tunnel (Belgium) was investigated by the use of x-ray and electron microprobes in order to detect any seasonal variations present in the chemical data and to make a comparison with meteorological data. The uniqueness of this speleothem system is that it is human constructed, controlled from the chronological point of view and with complete temperature and hydrological documentation. The Godarville tunnel stalagmites started to form since the time of closing down of the tunnel in 1960 and continued until the collection of the samples in December 1992. The growth of the annual laminae was observed on the cross-sections of several stalagmites and attributed to consecutive years and even seasons. The laminar structure, ascribed to seasonal variations, is very clear and formed by a set of alternating bright, porous and dark, compact calcite layers. This structure gave rise to the optical profiles of the annual variability that were compared with the x-ray synchrotron-based microprobe chemical profile data obtained at LURE (Orsay University, France). Using this method, several profiles were measured: Ca as the main element, Sr as a very important minor component and Fe, Zn, Pb and Br as trace elements. The results display an impressive correlation between the spatial distributions of Sr and Br with the optical linear profile of the sample, demonstrating that these elements also have a seasonal variation in the stalagmite layers. The Fe, Zn and Pb concentration profiles were characterized by sudden and random increases in contents (up to 20 times over background levels) whose origin is still uncertain. The results were supplemented by similar linear scan measurements made by the electron microprobe. The results show that Sr concentrates in the bright layers whereas the Mg spatial distribution is less correlated with the optical linear scan. A strontium-rich layer is formed during the autumn/winter periods. It is consistent with the ways of inclusion of that element in calcite, with the temperature-dependent and hydrological aspects.

The distribution of about twenty inorganic elements was traced in the skeletons of black corals of the Antipathes sallx species. Electron microprobe and PIXE mappings revealed the peculiar structure of this material, composed of the large cells (arranged in annual rings), surrounded by thin layers with an elevated level of iodine (up to 5%). Our current knowledge of the chemical composition of these corals' skeleton is not complete. Essentially the organic skeleton is saturated with inorganic elements and several of these could be commercially important. In fact, they have never been investigated for biomedical applications. In this preliminary current work, black corals from the Antipathes salix species were studied with the aim of detecting the inorganic components of their matrix and their suitability as biomedical materials.

A piece of stalagmite from a cave in Winthertore, Belgium, was analysed by the use of capillary tabletop and synchrotron versions of X-ray microprobes and then by the electron microprobe. The potential of these microprobes was tested for the first time in the study of such specific periodic objects. Indirect measurements of the morphology/density of samples were made by the use of Compton and Rayleigh scattered radiation in the X-ray tabletop microprobe and a selected channel in white scattered radiation in the X-ray synchrotron microprobe. In the electron microprobe, the linear profile extracted from the grey-scale transformation of the secondary electron image was used for the same purpose. The elemental analyses were superimposed on the density characteristics of the samples. The inclusions of iron and silicon, measurements of the magnesium/calcium/strontium/barium ratio, profiles of anionic species and the noticeable presence of iodine were among the most important findings. Some of the measured parameters probably allow the creation of thermometric scales for the potential estimation of the climatic conditions during the deposition of the calcite material.

The probability density functions Phi(rho z) for electrons, positrons and protons as well as for the ionizations [phi(rho z)] caused in the samples by the primary beams of the above mentioned particles have been studied. All of the dependencies obey Weibullean statistics. It has been shown that the probability density functions for the distribution of electrons as well as for positrons can be expanded from the conventional energy region of tens of keV to the region even closer to 1 MeV. The only difference is the disappearance of the surface charging in the high-energy region. A similar Phi(rho z) curve has been shown for the first time also for protons. The family of the ionization curves phi(rho z) seems to tend to be enveloped by the respective probability density curve Phi(rho z) for the distribution of the charged particle beam of the given energy. This has been shown for different tracers in a copper matrix. Given the probability density functions, one can easily select the correct solutions for the simulations of the particle beam attenuation in ambiguous situations; e.g., for 10 keV positrons penetrating a copper matrix it has been shown that the only proper energy-loss functions used in the simulations were those taking 11 and not 2 valence electrons into account.

0305-4403/$ e see front matter 2010 Elsevier Ltd. doi:10.1016/j.jas.2010.03.014 L. Backwell Bernard Price Institute for Palaeontological Research, School of Geosciences, University of the Witwatersrand, Private Bag 3, WITS 2050, Johannesburg, South Africa Unfortunately I was not informed that this paper was submitted, and was not shown galley proofs, so could not correct the following before publication

A set of trigonometric equations is derived for deterministic x-ray tracing in capillaries. A variety of capillary shapes is encompassed by this approach. The resulting reflectivity coefficients, gain factors, and angular beam divergence are determined. The results can also be applied to the case of neutron and proton guiding in narrow pipes.

The matrix effects which exist in x-ray fluorescence analysis are considered, Shiraiwa and Fujino equations being the initial point of these considerations. Matrix effects are divided into two groups: simple and so-called unusual. Among the simple ones, absorption and enhancement effects are considered. New concepts of ‘absolute’ and ‘relative’ absorption effects are introduced. It is shown that the expressions of simple matrix effects can be easily separated in the Shiraiwa and Fujino equation. Additionally, the unusual matrix effects, including the Birks-Harris effect and some cases of the Mitchell-Kellam effects, were found to be well described by certain equations based on the Shiraiwa and Fujino equation, provided the appropriate assumptions were made.

In connection with progress in the creation of differential and so-called differential methods of concentration correction, work has been carried out on the ordering of equations. It has been shown that it is possible to create three principal, complete systems of so-called differential concentration correction equations by (1) using the Claisse method, (2) using the method of function expansion in a Taylor series and (3) using a special method discussed in this paper. These equations can be used instead of the classical concentration correction methods. Moreover, it has been proved that the respective procedures can be used in the creation of expressions which are the analogues of classical intensity correction equations.

Particular attention is paid to the fact that both fundamental parameter equations and concentration correction equations derived from these are a function of all the elements present in the sample. Consequently any concentration correction equation created on the basis of spectral data relating to a single element may be used for the determination of another element concentration. In this paper we present sets of equations for three circumstances: for spectral lines belonging to all elements, for spectral lines belonging to one element only, and for a mixture of these two conditions.

This paper considers some limiting values of matrix effects on the basis of the version of the Shiraiwa and Fujino equation which takes into account matrix effects, expressed explicitly. It has been proved that one can obtain the limiting values of absorption and enhancement effects in those cases in which the concentration of the matrix element j tends to unity, and boundary values of absorption and self-absorption effects in the case when photons of exciting x-ray radiation have energies that considerably exceed the value of the absorption edge of the analysed element i. In addition, the limit of the enhancement effect at the point of the absorption edge of the matrix element j is given. A hypothesis is formulated concerning the linearity of the reciprocal of the enhancement function versus the concentration of the enhancing element j. This implies new important solutions of the Tertian equation, at least in the case of monochromatic excitation. The notion of effect equilibrium points and a search for them were also considered. Effect equilibrium points were registered as a consequence of concentration changes and also of changes in the exciting radiation energy.

A new approach to problems associated with enhancement effects in XRF analysis, and by analogy to analysis by electron microprobe and PIXE, is discussed. The concept of enhancement as ‘relative excess absorption’ is introduced. This concept allows an arrangement of mass balances in which the concentration of any given element may be derived explicitly from a set of relationships equivalent to fundamental expressions, such as the Lachance–Traill and Tertian equations for monochromatically excited XRF and the Claisse–Quintin equations for polychromatic excitation. In this new approach the values of μk′(λi or Ei) may be derived, and carry the meaning of apparent mass absorption coefficients for absorption and enhancement effects characteristic of any given pair of elements. Finally, some obvious convergences between XRF, electron microprobe and PIXE analyses are emphasized.