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In the field of mechanochemistry, the exact nature of the atomistic processes underlying physical and chemical transformations under mechanical processing conditions is a long-standing problem. Far from being satisfactorily solved, the lively debate associated has constantly stimulated the development of conceptual frameworks alternative to the defect-enhanced thermal diffusion scenarios initially proposed. Different approaches laying emphasis on the capability of mechanical forces to induce atomic scale mixing phenomena independent of thermal contribution were thus investigated. Along this line of inquiry, molecular dynamics simulations were here employed to gain deeper insight into the atomic-scale processes induced at the phase boundary between crystalline Ni and Zr metal lattices by the application of a shear stress. The numerical findings show that the application of shear stresses determines the deformation of the crystal and the formation of a sliding interface. Atoms with defective coordination appear at the interfacial region and gradually arrange into complex aggregates, the dynamics of which promotes the migration of atomic species and their gradual mixing near the interface. Chemical disordering processes take place at the interface, resulting in the formation of an amorphous domain.

With this article, we provide an overview of the methods, instruments and initiatives for forest biomass observation at global scale. We focus on the freely available information, provided by both remote and in-situ observations. The advantages and limitation of various space borne methods, including optical, radar (C, L and P band) and LiDAR, as well as respective instruments available on the orbit (MODIS, Proba-V, Landsat, Sentinel-1, Sentinel-2 , ALOS PALSAR, Envisat ASAR) or expecting (BIOMASS, GEDI, NISAR, SAOCOM-CS) are discussed. We emphasize the role of in-situ methods in the development of a biomass models, providing calibration and validation of remote sensing data. We focus on freely available forest biomass maps, databases and empirical models. We describe the functionality of Biomass.Geo-Wiki.org portal, which provides access to a collection of global and regional biomass maps in full resolution with unified legend and units overplayed with high-resolution imagery. The Forest-Observation-System.net is announced as an international cooperation to establish a global in-situ forest biomass database to support earth observation and to encourage investment in relevant field-based observations and science. Prospects of unmanned aerial vehicles in the forest inventory are briefly discussed.

Complexes ZnLCl₂ (I) and [CdLCl₂] _n (IV), where L is chiral bis -pyridine containing fragments of natural monoterpenoide (-)-a-pinene are synthesized. Single crystals of [ZnLCl₂]×CH₂Cl₂ (II), [ZnLCl₂]× i -PrOH (III), and IV compounds are grown. The crystal structures of II and III are composed of mononuclear ZnLCl₂ complex molecules and solvate CH₂Cl₂ and i -PrOH molecules; the coordination polyhedron of the zinc atom Cl₂N₂ is a distorted tetrahedron. According to the single crystal XRD data, complex IV is a 1D coordination polymer; the coordination core CdN₂Cl₄ is a distorted octahedron and Cl atoms are bridging ligands. In the structures of II, III, and IV the L molecule functions as a bidentate chelate ligand. In the solid phase, complexes I and IV exhibit photoluminescence in the visible range (l_max 505 nm and 460 nm respectively). The band intensity in the photoluminescence spectra of I and IV complexes considerably exceeds the band intensity in the spectrum of free L.

Palladium(II) and copper(II) complexes with 2-(2,2-dimethylhydrazone) pentanone-4 are synthesized for the first time. The compounds are characterized by IR and NMR spectroscopy, elemental and single crystal X-ray diffraction analyses. The palladium complex crystallizes in the space group I 4₁/ a ; the copper complex crystallizes in the space group P . Both compounds are molecular; the palladium chelate core has a distorted square geometry and that of copper has a distorted tetrahedral geometry. The average M-O and M-N bond lengths are respectively 1.9808(15) Å and 2.0427(17) Å for M = Pd, 1.915(8) Å and 1.97(1) Å for M = Cu. The chelate O-M-N angles are 88.32(7)-91.67(7)° for M = Pd, 93.37(4)-99.02(5)° for M = Cu.

A gradient chemical structure of micron-sized crystals of CuCrS₂ and CuCr_{1- x} V _x S₂ powders is established by the differential dissolution technique. It is shown that their surface region coherently conjugated with planar faces of CuCrS₂ crystals is enriched with copper whereas the bulk is depleted of copper and the copper sublattice is disordered. A possible mechanism of the formation of surface regions due to a high bulk mobility of copper atoms in the defect copper sublattice is proposed. It is shown that for solid solutions the disordering process involves copper and vanadium atoms and vacancy complexes. The phenomena found are discussed together with the structural and magnetic data.

A low-temperature plasma enhanced chemical vapor deposition procedure is developed for hexagonalого boron nitride nanowalls that are an array of sheets vertically aligned relative to the Si(100) substrate. A triethylaminoborane and ammonia gas phase was used for the first time to form h-BN nanowalls. Nanowall sizes are 50-250 nm long and 10-25 nm thick. Grazing incidence X-ray diffraction and high-resolution transmission electron microscopy techniques are employed to study the structures of boron nitrideх nanowalls. The effect of synthesis parameters (film deposition temperature and growth time) on the chemical and phase compositions, surface morphology, film structure, and their optical properties are analyzed.

FTIR spectroscopy is used to study the distribution of bulk (free) and hydration (bound) water during the extraction of Au(III) and Pt(IV) from acid sulfate-chloride media by reverse micelles consisting of non-ionic (Triton N-42) and anionic (AOT) surfactants. It is shown that the bulk water fraction increases with an increase in the anionic AOT concentration and that of hydration water increases with an increase in the non-ionic Triton N-42 concentration. A decrease in the bulk water fraction and an increase in the hydration water content enhance the extraction capacity of mixed micelles.

Stable colloidal dispersions with a 2 mM TiS₃ concentration (300 mg/l) are obtained by ultrasonic treatment of TiS₃ in acetonitrile and isopropyl alcohol and characterized by physicochemical methods. The electrical double layers for the particles in dispersions are estimated from the measured z-potentials, and the energies of interparticle interactions are calculated based on the Derjaguin-Landau-Verwey-Overbeek theory. The structural and spectroscopic identity of the particles and crystalline TiS₃ is demonstrated for the solid phases obtained from the dispersions.

A comparative study of the structural features of zinc 2,9,16,23-tetra- tert -butylphthalocyanine films (ZnPc( ^t Bu)₄) obtained by vacuum thermal deposition and spin coating techniques is performed. By powder X-ray diffraction, 2D GIXD, and optical absorption spectroscopy it is shown that ZnPc( ^t Bu)₄ films obtained by the spin coating technique consist of a disordered a-phase with small crystallites. After annealing at 200 °C for 3 h the films transform into the b-phase, with crystallite sizes increasing, however, they remain disordered relative to the substrate surface. On heating under the same conditions, the ZnPc( ^t Bu)₄ films obtained by thermal vacuum sublimation transform from the weakly oriented low-temperature a-phase into the oriented b-phase. Dependences of a chemiresistive sensor response of the ZnPc( ^t Bu)₄ films to ammonia (10-50 ppm) are investigated depending on the preparation and annealing methods of the films.

Three new metal-organic coordination polymers (H₂NMe₂)₂[Li₃(btc)(Hbtc)(DMF)₄] (1), [Li₅(DMF)₆(btc)(Hbtc)]×2DMF (2), and [Li₆(DMF)₈(bdc)(Hbtc)] (3) (H₃btc is trimesic acid, H₂bdc is terephthalic acid) are prepared by heating LiOH with different aromatic carboxylic acids in dimethyl formamide (or its mixture with water). The crystal structures and composition of the compounds are determined by single crystal X-ray diffraction. Compound 1 has a layered structure; compounds 2 and 3 have a framework structure.