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Despite progress in computer automated solutions, constitutional isomer verification by NMR using one‐ and two‐dimensional data sets is still, in the main, a manual, user‐intensive activity that is challenging for a number of reasons. These include the problem of simultaneously keeping track of the information from a number of separate NMR experiments and the difficulty of another researcher subsequently verifying the assignments made without having to independently repeat the whole analysis. This paper describes a graphical interactive approach that overcomes some of these problems. By using concepts used to visualise graph networks, we have been able to represent the NMR data in a manner that highlights directly the link between the different NMR experiments and the molecule of interest. Furthermore, by making the graph networks interactive, a user can easily validate and correct the assignment and understand the decisions made in arriving at the solution. We have developed a usable proof‐of‐concept computer program, 'simpleNMR', written in Python to illustrate the ideas and approach. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) using the generalized gradient approximation (GGA) made it possible to optimize the crystal structure, calculate the lattice parameters and band structure of (M = Ga, In) semiconductor compounds with a monoclinic structure (space group , no. 15). DFT calculations of the structure of compounds were expanded using two exchange-correlation functionals GGA-PBE and GGA + (U is the Coulomb parameter) with a value of = 2.1 eV (effective interaction parameter). Thermal diffusion coefficients () of atoms of individual types (α), i.e. atoms of thallium, gallium, indium and sulfur near the melting point of the compound were calculated by the molecular dynamics (MD) method. The values of atoms were obtained in the local neutrality approximation using the canonical MD ensemble. The values of the atoms were corrected to take into account the root-mean-square displacements of the atoms at a given time and temperature. The dependences of atoms, described by the Arrhenius law, were constructed. The activation energy of atomic diffusion was calculated. [ABSTRACT FROM AUTHOR]

In the era of the Internet of Things, photonic neuromorphic computing presents a promising method for real-time, local processing of vast quantities of data. However, the rigidity of materials used in such devices can considerably impact performance and longevity when subjected to mechanical deformation. In this study, we introduce a liquid optical memristor (LOM) based on an organic-inorganic hybrid in a liquid state. This novel approach offers programmable optical properties and significant mechanical flexibility thanks to the robust photochromic and capillary effects. We have developed a LOM with a 24 dB cm ^−1 modulation depth and over 3-bit nonvolatile memory states. By controlling the droplet morphology to mimic a synapse-like shape, the LOM can withstand strains over 400% and endure misalignment and bending. Furthermore, our findings substantiate the application of LOM for photonic neuromorphic computing systems, yielding 100% accuracy in pattern recognition. The easily-integratable LOM paves the way for the creation of flexible and wearable photonic neuromorphic computing systems.

Thermophysical properties of solid and liquid calcium (99.75 wt % pure) were experimentally studied with high accuracy in the temperature range 720–1290 K using dilatometer measurements, gamma-ray attenuation measurements (the gamma-ray method), high-temperature drop calorimetry, and the laser flash method. The behaviors of the density, enthalpy, and thermal conductivity of calcium in the fusion–crystallization region were studied. The enthalpy of fusion was measured as 8075 J/mol, the relative density change upon fusion as 3.3%, and the relative change in thermal conductivity upon fusion as 26%. The results were compared to the respective values in the related literature. The measurements at temperatures above 720 K either significantly amend the available literature data, or are currently unique. The constancy of the heat capacity of liquid calcium in the temperature range 1115–1290 K was verified. Fitting equations were derived, and recommended values of the investigated properties of calcium were tabulated for 720–1290 K, the temperature range where calcium is in the condensed state. [ABSTRACT FROM AUTHOR]

Molecular self‐diffusion coefficients underlie various kinetic properties of the liquids involved in chemistry, physics, and pharmaceutics. In this study, 547 self‐diffusion coefficients are calculated based on all‐atom molecular dynamics (MD) simulations of 152 diverse pure liquids at various temperatures employing the OPLS4 force field. The calculated coefficients are compared with experimental data (424 extracted from the literature and 123 newly measured by pulsed‐field gradient nuclear magnetic resonance). The calculations well agree with the experimental values. The determination coefficient and root mean square error between the observed and calculated logarithmic self‐diffusion coefficients of the 547 entries are 0.931 and 0.213, respectively, demonstrating that the MD calculation can be an excellent industrial tool for predicting, for example, molecular transportation in liquids such as the diffusion of active ingredients in biological and pharmaceutical liquids. The self‐diffusion coefficients collected in this study are compiled into a database for broad researches including artificial intelligence calculations. [ABSTRACT FROM AUTHOR]

The existence of the phenomenon of the electrochemical phase formation in metals and alloys via a supercooled liquid state stage is further discussed. In order to experimentally verify the existence of the phenomenon in question, the shapes of metal deposits subjected to the action of a centrifugal force parallel to the crystallization front in the course of electrodeposition were studied. The idea of the performed studies was that if the phase formation in the electrodeposited metal actually passes the stage of the liquid state, then under a low force exerted on a metal parallel to the crystallization front, one should expect a change in the shape of the deposits in the direction of the applied force. The results of the performed experiments made it possible to establish the effect of a change in the shapes of metal deposits electrodeposited under a low force applied parallel to the crystallization front, including a thickening of the deposit edge which is distant in the direction of the force action, its deformation, and elongation. The established effect is one more proof for the existence of the phenomenon under discussion. [ABSTRACT FROM AUTHOR]

The glass transition is described as a time- and history-independent singular event, which takes place in an interval dependent on the distribution width of molecular vibration amplitudes. The intrinsic glass transition is not seen as a relaxation phenomenon, but is characterized by a fixed volumetric state at the glass temperature Tg0. The relaxation behavior of the transport properties depends on the distance to Tg0. Free volume is redefined and its generation is the result of the fluctuating transfer of thermal energy into condensed matter and the resulting combined interactions between the vibration elements. This creates vacancies between the elements which are larger than the cross-section of an adjacent element or parts thereof. Possible shifts of molecules or molecular parts through such apertures depend on the size and axis orientation and do not require further energetic activation. After a displacement, additional volume is created by delays in occupying abandoned positions and restoring the energetic equilibrium. The different possibilities of axis orientation in space result in the different diffusive behavior of simple molecules and chain molecules, silicate network formers, and associated liquids. Glass transformation takes place at a critical volume Vg0 when the cross-section of apertures becomes smaller than the cross-section of the smallest molecular parts. The glass transition temperature Tg0 is assigned to Vg0 and is therefore independent of molecular relaxation processes. Tg0 is well above the Kauzmann and Vogel temperatures, usually just a few degrees below the conventionally measured glass temperature Tg(qT). The specific volume at the two temperatures mentioned above cannot be achieved by a glass with an unordered structure but only with aligned molecular axes, i.e. in a crystalline state. Simple liquids consisting of non-spherical molecules additionally alter their behavior above Vg0 at Vgl where the biggest gaps are as small as the largest molecular diameter. Tgl is located in the region of the crystalline melting point Tm. Both regions, above and below Tm, belong to different physical states and have to be treated separately. In the region close to Vg0 respectively Tg0, the distribution of vibration amplitudes has to be taken into account. The limiting volume Vg0 and the formation of apertures larger than the cross-section of the vibrating elements or parts thereof, in conjunction with the distribution width of molecular vibrations as Vg0 is approached, and the spatial orientation of the molecular axes is key to understanding the glass transition.

The existence of the phenomenon of electrochemical phase formation in metals and alloys via a supercooled liquid state stage is continued to be discussed. For experimental verification of the existence of the phenomenon in point, the surface morphology of metal deposits subjected to the action of a centrifugal force directed parallel to the crystallization front during the electrodeposition process was studied. The idea behind the studies was that if a metal passes the stage of a liquid state in the process of electrochemical phase formation, then a low force exerted on the growing deposit parallel to the crystallization front should expectedly cause its mass to move in a wavelike flow of continuously renewed liquid surface layers. The performed experiments detected a wavelike flow of the surface layers of metal deposits which were electro-depositing under a low force applied parallel to the crystallization front, including the curving of waves by mechanical obstacles and the appearance of foam on the wave crests. The established effect was another proof for the existence of the phenomenon under discussion. [ABSTRACT FROM AUTHOR]

The existence of the phenomenon of the electrochemical phase formation in metals and alloys via a supercooled liquid state stage is further discussed. In order to experimentally verify the existence of the phenomenon in point, the density of metal deposits subjected to the action of a centrifugal force applied perpendicular to the crystallization front during the electrodeposition process was studied. For this purpose, an installation and electrochemical cells were developed and manufactured, which ensures of metals electrodeposition under the conditions of a low force impact, in the field of a centrifugal force, in particular. The performed experiments identified the effect of an increase in the density of metal deposits under a low force superimposed perpendicular to the crystallization front during the electrochemical phase formation. This effect was confirmed by a decrease in porosity and a decline in the intensity of the X-ray diffraction maxima from the metal electrodeposits obtained under the impact of the conditions mentioned above. The identified effect is another proof for the existence of the phenomenon under discussion. [ABSTRACT FROM AUTHOR]

Rare earth organic complex materials have attracted tremendous attention for their intrinsic properties and promising practical applications. It is still a great challenge to realize the rare earth organic complex materials with excellent functional properties and diversified structural states. Here, the amino acid rare earth surfactant complexes of lanthanum octanoyl-alaninate (La(oct-ala)3), lanthanum octanyl-serinate (La(ser-oct)3) and lanthanum octanoyl-phenylalaninate (La(oct-phe)3) were synthesized by the reaction of C11H21NO3, C11H21NO4, C17H26NO3 with LaCl3, respectively. As-synthesized complexes of La(oct-ala)3 and La(oct-phe)3 have high solubility in pure solvent, while the solubility of La(ser-oct)3 is very low in pure solvent. When the concentration of the complex solution is lower than the critical micelle concentration, the dissociation phenomenon of the complex is occurred in the solution. When the concentration of the complex solution is greater than the critical micelle concentration, the dissociated ligand ions and metal ions will associate, which can form micelle aggregates. In addition, the aggregates of the complex gradually shrink to form aggregates of different sizes and sizes as the solvent continues to volatilize. By further heating and cooling, the glassy, crystalline, liquid crystal and other complexes can be obtained. The rare earth organic low molecular complexes formed by the combination of these rare earth ions and amino acid ligands can not only obtain the complexes with high rare earth content, but also have the excellent properties of convenient synthesis, high yield, easy processing, good solubility, low toxicity and high stability, etc., which can play the special physical and chemical functional characteristics of the diversified structure state of rare earth organic molecular materials. Therefore, in present work, the lanthanum complexes as a functional molecular materials have potential applications in many fields.

The aim of this work was the further experimental verification of the existence of the phenomenon of electrochemical phase formation in metals and alloys via a supercooled liquid state stage. Assuming that the phase formation in electrodeposition of metals involves occurrence of some deeply supercooled metallic liquid and its subsequent ultrarapid solidification, it was suggested that quasicrystals may be present in deposit layers next to the cathode. A further suggestion was that such electrochemical phase formation via metal's supercooled liquid state must present a possibility to produce electrodeposits in the form of phases with completely quasicrystalline structure. It was found that the phenomenon under study here is proved by the following experimental facts: (1) occurrence of quasicrystals in electrodeposit layers next to the cathode, a behaviour similar to that in interface-near metal layers at crucible walls in ultrarapid solidification of a deeply supercooled melt; and (2) electrochemical phase formation in metals resulting in phases with quasicrystalline structure when formation of a periodically ordered crystal structure is hindered in the course of deposition. [ABSTRACT FROM AUTHOR]

The purpose of this work was further experimental verification of the existence of the phenomenon of electrochemical phase formation in metals and alloys via a supercooled liquid state stage. It was assumed that replacing a solid cathode with a chemically identical liquid one would lead to higher electrochemical reduction rates of ions of the electrodepositing metal/alloy. The experimentation involved a cathode of Wood’s alloy having melting point at 68.5 °С. The electrocrystallization of some metals (Ni, Co, Fe) and alloys (Fe-Сr, Fe-Сr-Ni) was carried out at 65 °C with a solid cathode and at 75 °C with a liquid one. The experimentation revealed the anticipated electrochemical features of the interface between a cathode in its predetermined state of aggregation and the electrodepositing metal or alloy in full measure. It was concluded that the phenomenon of electrochemical phase formation in metals and alloys via supercooled liquid state stage is proved by the deionization acceleration in electrodepositing metals and alloys on replacing a solid cathode with a chemically identical liquid one.

In order to provide further evidence on the existence of the phenomenon of electro-chemical phase formation in metals and alloys via a supercooled liquid state stage, a set of experiments were carried out to reveal the predicted structural features in alloys during electrochemical phase formation at chemically identical solid or liquid cathode. In the third part of the research, the results of the precision X-ray phase analysis for the interface between an electrodepositing alloy in the form of intermetallic compounds and a cathode of Wood's alloy that persisted in either a solid or a liquid condition are discussed. The phenomenon in question was proved by the following experimental results: (1) alloys electrodepositing as intermetallic compounds at a solid metallic cathode showed formation of intermetallics involving components of the depositing alloy and, in parallel, cathode elements and alloy components; (2) on replacing a solid cathode with a chemically identical liquid one for alloys electrodepositing as intermetallic compounds, occurrence of additional intermetallics enriched in the major alloy component and cathode elements was observed. [ABSTRACT FROM AUTHOR]

Rare earth organic complex materials have attracted tremendous attention for their intrinsic properties and promising practical applications. It is still a great challenge to realize the rare earth organic complex materials with excellent functional properties and diversified structural states. Here, the amino acid rare earth surfactant complexes of lanthanum octanoyl-alaninate (La(oct-ala) 3), lanthanum octanyl-serinate (La(ser-oct) 3) and lanthanum octanoyl-phenylalaninate (La(oct-phe) 3) were synthesized by the reaction of C 11 H 21 NO 3 , C 11 H 21 NO 4 , C 17 H 26 NO 3 with LaCl 3 , respectively. As-synthesized complexes of La(oct-ala) 3 and La(oct-phe) 3 have high solubility in pure solvent, while the solubility of La(ser-oct) 3 is very low in pure solvent. When the concentration of the complex solution is lower than the critical micelle concentration, the dissociation phenomenon of the complex is occurred in the solution. When the concentration of the complex solution is greater than the critical micelle concentration, the dissociated ligand ions and metal ions will associate, which can form micelle aggregates. In addition, the aggregates of the complex gradually shrink to form aggregates of different sizes and sizes as the solvent continues to volatilize. By further heating and cooling, the glassy, crystalline, liquid crystal and other complexes can be obtained. The rare earth organic low molecular complexes formed by the combination of these rare earth ions and amino acid ligands can not only obtain the complexes with high rare earth content, but also have the excellent properties of convenient synthesis, high yield, easy processing, good solubility, low toxicity and high stability, etc., which can play the special physical and chemical functional characteristics of the diversified structure state of rare earth organic molecular materials. Therefore, in present work, the lanthanum complexes as a functional molecular materials have potential applications in many fields. [ABSTRACT FROM AUTHOR]

The existence of the phenomenon of electrochemical phase formation in metals and alloys via a supercooled liquid state stage has been discussed. In the second part of the research, the results of the precision X-ray phase analysis for the interface between electrodepositing alloy in the form of a substitutional solid solution and a cathode of Wood's alloy that persisted in either a solid or a liquid condition are considered. It was found that the phenomenon under study here is proved by the following experimental data: (1) the formation of intermetallics between solid metallic cathode elements and the solvent in the alloy electrodepositing as substitution solid solution, and enhancement of these processes accompanied by the development of additional intermetallics enriched in cathode elements on replacing a solid cathode with a chemically identical liquid one; (2) with alloys electrodepositing as substitution solid solution at a solid metallic cathode, the formation of intermetallics including cathode elements and the alloy solute element building no distinct phase; and (3) on replacing a solid cathode with a chemically identical liquid one, enhanced intermetallic formation involving metallic cathode elements and the electrodepositing alloy solute building no distinct phase plus emergence of additional intermetallics enriched in cathode elements. [ABSTRACT FROM AUTHOR]

The existence of the phenomenon of electrochemical phase formation in metals and alloys via a supercooled liquid state stage is discussed. In dealing with that subject in terms of emergence and ultrarapid solidification of a deeply supercooled metallic liquid represented by a multitude of liquid atomic clusters, an idea was put forth that an identity of the state of aggregation between the cathode and the electrodepositing metal/alloy at the cathode–deposit interface must facilitate phase transformations at the interface. It was assumed that replacing a solid cathode with a chemically identical liquid one would lead to a wider spectrum of intermetallics formed due to interactions of the electrodepositing metal with elements of the liquid metallic cathode. Precision X-ray phase characterization was performed for the interface between the electrodepositing metal and a cathode of Wood's alloy that persisted in either a solid or a liquid condition through the electrodeposition process. Relying on the data obtained, it was concluded that the phenomenon in point is proved by the formation enhancement of intermetallic compounds involving metallic cathode elements and the electrodepositing metal plus evolvement of additional intermetallics enriched in cathode elements, on replacing a solid cathode with a chemically identical liquid one. [ABSTRACT FROM AUTHOR]

The phenomenon of electrochemical phase formation in metals via a supercooled liquid state stage is discussed. Experiments are carried out aiming to verify its existence. It is found that the amorphous structure typical of a solidified metallic liquid did form in the course of metals electrodeposition when crystallization is hindered. The experimental findings verify the existence of the phenomenon of electrochemical phase formation via a stage of a supercooled liquid state. [ABSTRACT FROM AUTHOR]

Raman spectroscopy was used to characterize the polymorphs and liquid state of anhydrous milk fat, with emphasis placed on the thermal evolution of the ester carbonyl stretching modes (1800–1700 cm −1 ) and the comparative study of the Raman-active C C (1660 cm −1 ) and C H (3000–2700 cm −1 ) vibrational modes. Specific Raman signatures in the crystalline phase were found and attributed to the coexistence of two groups of triglycerides. This was confirmed using differential scanning calorimetry and X-ray diffraction methods. In the ester carbonyl band, the effect of changing temperature on both the number of modes and new defined intensity ratios was studied and enabled polymorph discrimination. C H stretching signals increased with polymorph stability, indicating the dominance of antisymmetric C H methylene vibrations as the anhydrous milk fats crystal lattice became more ordered. The change in intensity of the C H stretching bands as a function of temperature was used to probe the order-disorder transition. [ABSTRACT FROM AUTHOR]

The electrical resistivity of IN 718 alloy was studied in a liquid state with contactless induction method of rotating magnetic field. Solidification process was studied by differential thermal analysis. It was founded that electrical resistivity varies in a complicated way with increasing temperature. It is shown that heating of the liquid metal above certain temperatures causes of hysteresis, i.e. discrepancy between the temperature dependences of heating and cooling. It was revealed, that the changes of niobium contents within alloy composition do not lead to a qualitative change of temperature dependence type, but accompanied by some peculiarities. Effect of titanium content on electrical resistivity changes within the alloy composition does not clearly detect. The temperature of maximal melt heating determines the degree of supercooling of liquid alloy.

Results of structural studies of metals electrodeposited exposed to an external force directed perpendicular or at an angle to the crystallization front have been described. It has been found that there is an increase in the dislocation density in metals electrodeposited exposed to a minor external force directed perpendicular to the crystallization front. It has been revealed that the surface layers of electrodeposited metals undergo plastic deformation caused by solid particles that move under the action of a minor external force directed at an angle to the crystallization front. It has been found that the solid particles leave imprints representing the particle shape and morphology at sites of separation from the surface of the metal electrodeposits formed exposed to a minor external force directed at an angle to the crystallization front. The existence of phase formation through a liquid state stage in electrodeposited metals has been proven. [ABSTRACT FROM AUTHOR]

The phenomenon of phase formation through a liquid state stage in metals being electrodeposited has been discussed. In order to provide further evidence on the existence of this phenomenon, a set of experiments are conducted to reveal the predicted structural features in metals exposed to a minor external force during electrodeposition. In the second part of the research, the results of structural studies of metals electrodeposited under the action of an external force directed perpendicular to the crystallization front are discussed. It is found that electrodeposition of metals exposed to a minor external force perpendicular to the crystallization front leads to a refinement of their intracrystalline structure and surface morphology. The experimental results prove the existence of the phenomenon of phase formation through a liquid state stage in metals being electrodeposited. [ABSTRACT FROM AUTHOR]

Liquid state manipulations on solidified Al-18%Si structures and properties were investigated based on its liquid abnormal resistivity-temperature behaviors (LARTB), which suggested a temperature-induced liquid-liquid structural transition (TI-LLST). The primary Si crystals are dramatically refined if solidified from the melt after LARTB range, compared with those before and during it. And then, solidified structures are further ameliorated by suitably mixing the high-temperature melt with low-temperature melt in semisolid state, generating increased tensile strength and ductility synchronously. This work elicits that liquid manipulations for optimizing materials structures and properties can be more effective if information suggesting TI-LLST is detected beforehand. [ABSTRACT FROM AUTHOR]

The state-of-the-art of the problem of crystal growth by electrolysis has been briefly discussed. A novel concept of phase formation in metals being electrodeposited has been formulated. Previous experimental findings that prove the occurrence of phase formation through a liquid state stage in metals being electrodeposited have been described. The general idea of this study is that the fundamental difference between the solid and liquid state of a metal lies in its differing ability to change the metal shape and structure under the action of a relatively small external force. With a view to providing further evidence on the existence of this phenomenon, a set of experiments has been conducted to confirm the predicted structural features in metals exposed to a minor external force during electrodeposition. In the first part of the research, the results of structural studies of metals electrodeposited under the action of an external force directed parallel to the crystallization front have been discussed. It has been found that electrodeposition with the exposure of metals to a minor external force parallel to the crystallization front leads to the formation of deposits of an anisotropic shape with a decreased roughness and a smoothed surface morphology. The experimental results prove the existence of the phenomenon of phase formation through a liquid state stage in the metals being electrodeposited. [ABSTRACT FROM AUTHOR]