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This work is devoted to the study of the composition of such a characteristic object for the 17–19 centuries as wafers, which were used to join sheets of paper in documents or to seal letters. Owing to the limited information in the literature and possible degradation processes that may occur with them in this paper, the modern optical techniques were applied to gain information about them. As the object of the investigation the wafers found in the hand-written documents of Academician Friedrich Georg Wilhelm von Struve (Vasily Yakovlevich Struve 1793–1864) were chosen (Fund number 721, the RAS Archive, Saint-Petersburg branch, Struve V.). Besides the common way it was found that a large number of colored wafers were used to join several sheets in one composite elongated document and also to make correction on top of what was written. As the part of a major task aimed at maintaining the fund documents dated 19th century and the stability of the used joining wafers in particular the Raman and UV–Vis absorbance spectroscopies were applied in order to investigate wafers chemical composition. It was found the use of two different types of pigments for orange hues. One of them is cinnabar and another one is made up of red lead and massicot mixture. The Prussian blue was used for wafers with dark blue hue and as a mixture with massicot for green hue. According to UV–Vis absorbance spectroscopy it was found the use of anthraquinone type pigment for the red, rose and purple hues. The presence of the wafers with different base materials were determined by means of the Raman spectroscopy, namely of the vegetable (presumably starch) and protein (presumably gelatin) origin. The obtained results were compared with the data available in the previous researches, including the recipes given in the publications of the 19th century. [ABSTRACT FROM AUTHOR]

• 19th c. Red Living Room plafond and their color palette. • Unique plafond in the distemper technique, safety more than 60%. • Raman microscopy as a tool to differentiate the pigments in mixture. • SERDS as a technique for pigments identification in the high luminescence media. • Relatively rare in nature pigment Trippkeite (CuAs 2 O 4). Within the framework of the restoration painted plafond performed in the distemper technique at the first half of the 19th century were investigated by micro-Raman spectroscopy, UV photography, optical microscopy. One hundred and fifty artistic composition fragments samples were studied from the different parts of plafond. The presence of the following basic pigments: emerald green, Scheele's green; ultramarine, indigo blue, azurites, vermilion, ferric oxide based pigments were observed. Lead white, calcite and gypsum were identified. It's ownership of the author's record is discussed. The places of pigments application in the author's layer of painting were localized, basic and auxiliary materials were identified. [ABSTRACT FROM AUTHOR]

Abstract It's shown suggested methods for diagnosing pathological processes in biological objects using a developed portable radiometric system with four gamma-ray detectors. Designed portable radiometric system was used to make 2D imaging of anatomical structures. The system can value pharmacokinetics in several points of wide area of interest at the patient body. In this study specially designed phantoms were used. Phantom models of the liver and blood circulation system were made to assay radiometric system. The construction concept and possible applications of the system in the practice of radionuclide diagnostic studies in vivo are presented. Highlights • Phantom models of the liver and heart were made to assay radiometric system. • Designed radiometric system was used to make 2D imaging of anatomical structures. • The system can value pharmacokinetics in several points of wide area of interest. • Dynamical parameters of blood circulation phantom were studied by the system. • The system can be used with a gamma-camera to extend its functionality. [ABSTRACT FROM AUTHOR]

Five major cereals such as wheat, rice, maize, barley and sorghum were among the first Neolithic crops that facilitated the establishment of the early agricultural societies. Since then they have remained the staple source of calories for the majority of the human population. Ample archaeological and molecular evidence has provided important insights into the domestication history of cereals but the debates on the origin of cereal crops are still far from resolved. Here, we review the recent advances in applying genome sequencing technologies for deciphering the history of cereal domestication. As a model example, we demonstrate that the evolution of thoughts on barley domestication closely followed the development of views on the rise of agriculture in the Near East in general and greatly accelerated with the advent of the genomic technologies and resources available for barley research. [ABSTRACT FROM AUTHOR]

• This is the first detailed study of laser irradiation effects on zinc heritage objects. • Metallic zinc ablation threshold is lower than zinc corrosion ablation threshold. • There is no self-limiting effect during zinc laser cleaning. • Laser pulses from μs to fs initiates yellowing of zinc corrosion products. In this work lasers with pulse durations from μs to fs were used to clean zinc heritage objects from atmospheric corrosion deposits. Wavelengths at 355, 532, 800, 1064 nm were tested. The surface was studied by Raman spectroscopy, Scanning electron microscopy, X-ray diffraction and optical microscopy. It was shown that for all lasers used there is no self-limiting cleaning effect, and the metal melting threshold is lower than the corrosion complete removal threshold. A femtosecond laser produces the least surface melting with 100 fs pulse duration, the shortest in this study. Yellowing of corrosion layers due to temperature modification of zincite was observed with irradiation by all lasers used. [ABSTRACT FROM AUTHOR]

• The 200 photographic artifacts belonging to the Karl Kosse family of the early XX century were investigated. • The Raman handheld portable spectrometer allows performing safe and informative artifacts investigation. • The nitrate cellulose base with camphor additions was identified. • The chemometric techniques helps to divide the measured samples into groups on the basis of mineral contributions. • The deterioration of polypropylene package and photographic surface was manifested. The study is devoted to the development of a safe and reliable methodology for investigation of photographic stereo negative films by methods of molecular spectroscopy using portable devices. The investigation of 200 photographic stereo negative films of the early XXth century that belonged to the Karl Kosse family photographic archive was performed. This archive was donated to the collection of the State Russian Museum and Exhibition Centre ROSPHOTO (St. Petersburg, Russia) in 2013. Due to the presence of artifacts with a different state of preservation, the study of the artifacts contributes to the understanding of the degradation processes and methods of the state control, approaches of restorations and conservations, as well as the historical development of the photographic industry and amateur photography of the late XIX - early XXth centuries. The portable Raman spectroscopy was selected as the informative technique, giving highly reproducible results. The film base was attributed to cellulose nitrate with the camphor addition for all studied artifacts. It was demonstrated that the safe and reliable results can be obtained with the help of portable Raman spectrometer BRAVO Bruker. Combination of principle component analysis with conjunction of hierarchical cluster analysis made it possible to divide the studied photographic materials into groups on the basis of relative contribution of inorganic compounds detected by Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Raman spectra of crystalline sulfur samples of the mixed isotopic composition (32S 8) 1−x (34S 8) x , where 0 ≤ x ≤ 1, have been studied. These spectra demonstrate synchronization of oscillations of S 8 molecules of the same isotopic composition which leads to "breathing" mode splitting at 211–216 cm−1 (Davydov splitting). The level of splitting depends on the molecule content of the corresponding isotope and attains its maximum value of 4.5 cm−1 for monoisotopic samples. If the molecules of different isotopic composition of 32S 8 and 34S 8 are adjacent, the difference in their eigen frequencies excludes the effect of splitting. For the other vibrational modes, the change in the relative content of 32S 8 and 34S 8 leads to proportional change in the intensity of the spectral bands with invariable frequencies of stretching vibrations or gradual change in the frequencies of lattice vibrations. [ABSTRACT FROM AUTHOR]

Herein, we present Cu K-edge XANES (X-ray Absorption Near Edge Structure) simulations for different framework interacting Z-CuII species proposed to form as an active site after high-temperature activation in Cu-exchanged chabazite zeolites, representing promising materials for selective catalytic reduction of NO x in the presence of ammonia and direct conversion of methane to methanol. We critically compare the simulated spectra to previously collected data for an O 2 -activated Cu-chabazite sample. Density of states (DOS) calculations allow us to get more insights in describing the nature of XANES features observed in the simulated spectra. To demonstrate the potential of the method, we finally explore the impact of systematic variations of selected structural parameters on the theoretical XANES features. • XANES simulations can be applied to discriminate between different CuII sites in CHA. • XANES can effectively distinguish three- and four-fold coordinated CuII species. • Simulations for modified models reflect the consecutive evolution of XANES spectra. • Partial DOS calculations allow to explore the origin of XANES features in Cu-CHA. [ABSTRACT FROM AUTHOR]

In this work, we focus on the simulated EXAFS spectrum of a Cu-oxo dimer sited in the eight-membered ring of the chabazite zeolite framework. We show the high level of complexity related to the analysis of the second and third shell of the EXAFS-Fourier transform due to the overlap of contributions stemming from different atomic species present in the Cu-local environment. Subsequently, we demonstrate the potential of Wavelet Transform Analysis as a new tool in the identification and visualization of EXAFS atomic contributions, providing an easier and effective interpretation of the data collected on Cu-zeolite systems. • High level of complexity emerges from the Cu-oxo dimer EXAFS analysis. • The simulated EXAFS second shell shows contributions coming from Cu, Al, framework. • Wavelet analysis provides a better identification of the EXAFS atomic contributions. • Wavelet analysis leads to a clear visualization of the Cu-Cu contributions. • This method will be applied on EXAFS spectra of Cu-CHA collected in O 2 at 500 °C. [ABSTRACT FROM AUTHOR]

BaAl 2 Si 2 O 8 (barium feldspar-based) materials are widely used in glass and ceramic industry due to high melting temperature, chemical resistance, low thermal expansion, low dielectric constants and attractive luminescence properties. The durability of barium feldspar ceramics strongly depends on reversible phase transitions between the low-temperature modification (celsian), and series of high-temperature (HT) polymorphs known as 'hexacelsian'. Numerous works have been devoted to the study of the thermal transitions of 'hexacelsian' by X-ray powder diffraction methods and transmission electron microscopy, the use of which provides limited information about structural changes. Here, the crystal structures, thermal properties and phase transitions of HT BaAl 2 Si 2 O 8 polymorphs are characterized for the first time using in-situ HT X-ray single-crystal structural study (SCXRD), and micro-Raman spectroscopy up to 1000 °C. The crystal structure of α-hexacelsian under ambient conditions is monoclinic (I 2/ a). The alpha-form undergoes two polymorphic transformations upon heating: into an orthorhombic (Fmmm) β-modification above 300 °C and into a hexagonal (P –62 m) γ-modification above 700 °C. These transitions lead to significant changes in the unit-cell volume: an obstacle in the production of BaAl 2 Si 2 O 8 -based ceramics. [ABSTRACT FROM AUTHOR]

This work presents the study of an XIII century French medieval Legendarium manuscript. The manuscript has a complex background of destruction and restoration attempts. Now the manuscript consists of 214 sheets encapsulated in polyethylene terephthalate conservation envelopes. The damaged manuscript sheets are in different states, some illustrations and text sections are in rather bad condition, some pages contain blurred traces of pigments and inks, which were used to write letters and make illustrations. Works carried out on this unique literary monument, included research using optical microscopy (OM), infrared reflectography (IRR), micro-Raman spectroscopy, and Scanning Electron Microscopy (SEM). The work was aimed at the estimation of the manuscript preservation and its current state. It has been demonstrated that even the study of micro-particles can be useful in the initial stages of the parchment manuscripts study that are in highly damaged condition. A wide variety of materials, which were used in different periods of time, have been found. Two types of red and four types of blue pigments were found in the studied particles from parchment. Locating the particles of iron-gall ink and pigments (for example, cinnabar and azurite) in the same region may indicate a possible use of this type of ink for both text and decoration. Pigments were revealed, the appearance of which date to a later time compared with the estimated date of Legendarium creations. These pigments include Prussian blue, pigments based on monoazo group and phthalocyanine blue. This contributes to the identification and localization of later interventions in the object under study, which were made both for the purpose of restoration and preservation. [ABSTRACT FROM AUTHOR]

Lithium-zinc-germanate glass-ceramics doped with Mn ions are synthesized by volume crystallization method. Structural studies show nucleation of different forms of lithium germanate crystals depending on the isothermal treatment regime of the initial glass. With the increase of the heat treatment temperature and the lithium content in the initial glass, the [GeO 4 ] /[GeO 6 ] ratio in the nucleated crystalline phases increases. The initial distribution of Mn2+/Mn3+/Mn4+ is defined by the Li 2 O/ZnO ratio in the glass composition: the ratio growth increases the contribution of Mn4+ over the Mn2+ and Mn3+. Low-temperature heat treatment of initial glass leads to uprise of intense red emission of Mn4+ ions in the octahedral environment. High-temperature heat treatment leads to occurrence of intense green emission related to Mn2+ ions in a tetrahedral environment. Discussions on all transformations of symmetry, the crystal field strength of Mn ions' environment and their valence state based on the results of optical spectroscopy, ESR and XRF studies are provided. The maximum quantum yield of red luminescence is 61%, and of green luminescence is 23%. The synthesized glass-ceramics can be used as a luminescent converter of the UV LED radiation with the maximum energy efficiency of 20%. [Display omitted] [ABSTRACT FROM AUTHOR]

Harmful cyanobacterial blooms (HCB s) have become a common issue in freshwater worldwide. Biological methods for controlling HCB s are relatively cost effective and environmentally friendly. The strain of ascomycete GF6 was isolated from a water sample collected from the estuarine zone of the eastern part of the Gulf of Finland. Based on cultural and morphological features and data of phylogenetic analysis, the strain was identified as Aspergillus welwitschiae GF6. The isolated GF6 strain has algicidal activity against both cyanobacteria and green algae. The highest sensitivity to the algicidal action of strain GF6 was found in cyanobacteria (98.5–100%). The algicidal effect on green algae did not exceed 63–70%. It was shown that GF6 strain exhibited an indirect attack mode by releasing metabolites that inhibit and/or degrade algal cells. In this study, significantly increased malondialdehyde content in Microcystis aeruginosa cells indicated that GF6 strain caused oxidative damage to the algal cell membrane. Enhanced production of phytosynthetic pigments, increase in lifetime chlorophyll a fluorescence and in the levels of antioxidants were noted in Microcystis aeruginosa cells. Besides this, GF6 strain could reduce the microcystins content in the medium under inhibiting the growth of M. aeruginosa. Apart from the growth inhibition and cell degradation of M. aeruginosa, GF6 strain is able to remove microcystin-LR (MC-LR). The content of MC-LR at an initial concentration of 0.51 μg/mL decreased by 61% after 72 h of A.welwitschiae GF6 strain cultivation. In the process of MC-LR biodestruction, transformation products were identified - the conjugate of microcystin with glutathione and the linearized form of MC-LR. The isolated strain with algicidal activity and the ability to degrade microcystin is of interest for further research in order to be able to use it for convergent technology to prevent the mass development of cyanobacteria and detoxification of cyanotoxins in water bodies. [Display omitted] • The algicidal fungus GF6 was isolated from a water of the Gulf of Finland. • The highest sensitivity to the algicidal action was found in cyanobacteria. • The GF6 strain caused oxidative damage to the algal cell membrane. • Algae adaptation was realized due to changes in the photo- and antioxidant systems. • The GF6 strain is able to degrade MC-LR. [ABSTRACT FROM AUTHOR]

We combine in situ XAS and DFT to determine the local structure of Cu(I) ions in the Cu-exchanged mordenite (MOR) zeolite, one of the most promising materials for the selective oxidation of methane to methanol. Data analysis points to a quasi-linear coordination geometry in the MOR side pocket and suggests that ca. 20% of the Cu-ions exist as coupled di-copper(I) species, paving the way for more detailed structural refinements. • DFT-assisted XAS allowed determining the local structure of Cu(I) ions in Cu-MOR. • Data analysis reveals quasi-linear Cu(I) sites coordinated to two framework oxygens. • High levels of disorder are detected in the second coordination sphere of Cu(I). • EXAFS supports long-range Cu−Cu contributions involving ca. 20% of the Cu ions. • Future studies will target to O 2 reaction with the Cu(I) species characterized here. [ABSTRACT FROM AUTHOR]

We report an accurate study of phase formation in the Zr4+/terephthalic acid system under MW heating at 220 °C. We have focused on water and/or acetic acid additives on the phase composition of the product. In our recent work, we have claimed that water plays a crucial role in UiO-66 phase formation during solvothermal synthesis. This trend was observed during MW synthesis as well. However, microwaves provide fast heat transfer, and it obstructs the formation of the high-symmetric UiO-66 phase and shifts the balance to MIL-140A formation even in the presence of water. Moreover, during solvothermal synthesis, acetic acid additive acts as a modulator and leads to the formation of a highly crystalline UiO-66 phase. Conversely, in MW conditions, acetic acid additive shifts the balance to the MIL-140A phase because it improves the capability of the reaction mixture to absorb microwaves and, therefore, to reach higher temperatures faster. In other words, we have observed two opposite trends in phase formation under MW irradiation – water additive provides ZrO 2 nuclei and shifts balance toward the UiO-66 phase, while fast MW heating results in MIL-140A. Image 1 • Phase formation in UiO-66/MIL140A system under MW treatment. • Fast heat transfer results in MIL-140A phase formation. • Acetic acid during solvothermal synthesis promotes UiO-66 formation. • Acetic acid during microwave synthesis promotes MIL-140A formation. [ABSTRACT FROM AUTHOR]

Graphical abstract The review is devoted to the X-ray absorption spectroscopies (XAS) which are among the most powerful techniques for characterization of local atomic and electronic structure of metal atmos in MOFs. XAS is element selective technique, sensitive to local atomic coordination, bond lengths and angles, oxidation state of metals atoms. Abstract After a short introduction highlighting the potentialities of metal–organic frameworks (MOFs) and the power of X-ray absorption spectroscopies (XAS), a list of selected examples follows. The first part of this review provides the basic concepts that are behind the most used XAS techniques: Extended X-ray Absorption Fine Structure (EXAFS) and X-ray Absorption Near Edge Structure (XANES) spectroscopies. Moreover, it reports also the basis of an innovative approach to the EXAFS data analysis based on the wavelet transform approach, that allows a more solid attribution to the different paths contributing to the overall signal. The second part is devoted to provide a section of examples where EXAFS and XANES techniques have been determinant in understanding the structural and electronic properties of metal centers in MOFs. The selected examples have been ordered in subsections related to the application foreseen for the investigated MOFs materials: MOFs functionalization for catalytic applications; MOFs as single site catalyst; MOFs as photocatalysts; MOFs for gas sorption and storage; MOFs for energy application. Conclusions and perspectives are provided at the end. [ABSTRACT FROM AUTHOR]

In this work, we studied a method of laser-induced coloration of metals, where small-scale spatially periodic structures play a key role in the process of color formation. The formation of such structures on a surface of AISI 304 stainless steel was demonstrated for the 1.06 µm fiber laser with nanosecond duration of pulses and random (elliptical) polarization. The color of the surface depends on the period, height and orientation of periodic surface structures. Adjustment of the polarization of the laser radiation or change of laser incidence angle can be used to control the orientation of the structures. The formation of markings that change their color under the different viewing angles becomes possible. The potential application of the method is metal product protection against falsification. [ABSTRACT FROM AUTHOR]