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Currently, new functional materials are being created with a strong emphasis on their ecological aspect. Materials and devices based on DNA biopolymers, being environmentally friendly, are therefore very interesting from the point of view of applications. In this paper, we present the results of research on complexes in the powder form based on plasmid DNA (pDNA) and three surfactants with aliphatic chains containing 16 carbon atoms (cetyltrimethylammonium chloride, benzyldimethylhexadecylammonium chloride and hexadecylpyridinium chloride). The X-ray diffraction results indicate a local hexagonal packing of DNA helices in plasmid DNA complexes, resembling the packing for corresponding complexes based on linear DNA. Based on the Fourier-transform infrared spectroscopy results, the DNA conformation in all three complexes was determined as predominantly of A-type. The two relaxation processes revealed by dielectric spectroscopy for all the studied complexes are connected with two different contributions to total conductivity (crystallite part and grain boundaries). The crystallite part (grain interior) was interpreted as an oscillation of the polar surfactant head groups and is dependent on the conformation of the surfactant chain. The influence of the DNA type on the properties of the complexes is discussed, taking into account our previous results for complexes based on linear DNA. We showed that the type of DNA has an impact on the properties of the complexes, which has not been demonstrated so far. It was also found that the layer of pDNA–surfactant complexes can be used as a layer with variable specific electric conductivity by selecting the frequency, which is interesting from an application point of view. [ABSTRACT FROM AUTHOR]

The experimental IR spectra of (S)-4′-(1-methylheptyloxycarbonyl) biphenyl-4-yl 4-[2-(2,2,3,3,4,4,4-heptafluorobutoxy) ethyl-1-oxy]-2-fluorobenzoate in the crystal phase are analyzed with the help of dispersion-corrected density functional theory (DFT+D3) calculations for isolated molecular monomer and dimer models, and a periodic model computed at the extended density functional tight-binding (xTB) level of theory. It is found that the frequency scaling coefficients obtained with the results of the molecular calculations are good matches for the crystal phase, being close to 1. The molecular and periodic models both confirm that varied intra- and intermolecular interactions are crucial in order to reproduce the broadened shape of the experimental band related to C=O stretching; the key factors are the conjugation of the ester groups with the aromatic rings and the varied intermolecular chemical environments, wherein the C=O group that bridges the biphenyl and F-substituted phenyl groups seems particularly sensitive. The C=O stretching vibrations are investigated as a function of temperature, covering the range of the crystal, smectic CA*, smectic C* and isotropic liquid phases. The structure changes are followed based on the X-ray diffraction patterns collected in the same temperatures as the IR spectra. The experimental and computational results taken together indicate that the amount of weak C=O...H-C hydrogen bonds between the molecules in the smectic layers decreases with increasing temperature. [ABSTRACT FROM AUTHOR]

One of the fundamental elements of a scientist's work is the ability to lead observations of the phenomena that surround us and based on them making conclusions. These observations are conducted within the so-called scientific experiments. Lessons learned based on the results obtained in experiments allow researchers to better understand the essence of the phenomena occurring in the world around us. Drawing conclusions is not always easy. In order to achieve this skill, we must possess a well-established knowledge in the field of the phenomenon that interests us. The most striking example of how important skills are observation and drawing proper conclusions is the phenomenon of global climate warming. The main parameter influencing temperatures registered on Earth is the concentration of greenhouse gases in the atmosphere, and especially carbon dioxide created from combustion processes. A significant role in studies of the reduction of CO2 emissions plays chemists. To be sure that conducted by them experiments are optimally designed, it is necessary to ensure them with proper education already at the secondary school level. The main aim of this article was to conduct the study in order to explain chemical issues that create the greatest cognitive difficulties among students. The second aim of the article was to propose a chemical experiment to students that would allow them to find out more about the phenomena governing in the area of problematic issues. The proposed experiment is based on the concept of solubility equilibrium. Results of preliminary tests that have been carried out after applying this experiment on a small group of students, indicated their better understanding of the studied subject. [ABSTRACT FROM AUTHOR]

Depression is one of the most common psychiatric issues with a proportion of adults with major depressive disorder who fail to achieve remission with index pharmacological treatment. There are unmet needs in ADT focus on non-monoaminergic agents. Accumulating evidence suggests that the N-Methyl-d-aspartate receptor (NMDAR) plays an important role in the neurobiology and treatment of major depressive disorder. The role of copper ions in pathogenesis and treatment of depression is not fully clarified, however interaction between copper and NMDAR is of prime importance. Release of copper ions inhibits NMDAR and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor function thus protects neurons from glutamatergic excitotoxity. Abnormalities in glutamatergic transmission are the key of glutamate hypothesis of depression. Some authors revealed that NMDARs are also regulated by cellular prion protein (PrPC) and indicated that interactions of copper, glycine and NMDARs subunits are vital for the regulation of the receptor. As NMDAR antagonist ketamine is known to produce rapid antidepressive effect, observation of copper serum levels in patients treated with ketamine may provide important information about connections between NMDAR antagonistic agents and trace elements antagonistic to that receptor. It is necessary to carry out further studies related to copper and ketamine in depression treatment. [ABSTRACT FROM AUTHOR]

Three (4,4′-((1E,1′E)-(2,5-bis(octyloxy)-1,4-phenylene)bis(ethene-2,1-diyl))bis-(E)-N-(2,5-bis(octyloxy)benzylidene)) imine derivatives were synthesized via a condensation reaction with p-toluenesulfonic acid as a catalyst. The effects of the end groups and vinylene (–HC=CH–) moieties on the structural, thermal, optical, electrochemical and photovoltaic properties of imines were investigated to check the influence of TiO2 on the imine properties. The thermal behavior of imines and their complexes with TiO2 was widely investigated using FT-IR, XRD, DSC and POM methods in order to determine the order type in the imine structure. All imines present the highest occupied molecular orbital (HOMO) levels of about −5.39 eV (SAI1 and SAI2) and −5.27 eV (SAI3) and the lowest unoccupied molecular orbital (LUMO) levels at about −3.17 eV. The difference of the end groups in the imines in each case did not affect redox properties. Generally, both oxidation and reduction are easier after TiO2 addition and it also changes the HOMO–LUMO levels of imines. Moreover, changes in the characteristic bands for imines in the region 1500–1700 cm−1 observed as a drastic decrease of intensity or even disappearance of bands in the imine : TiO2 mixture suggest the formation of a complex (C=N)–TiO2. Organic devices with the configuration of ITO/TiO2/SAIx (or SAIx : TiO2)/Au were fabricated and investigated in the presence and absence of visible light irradiation with an intensity of 93 mW cm−2. In all imines and complexes with TiO2, the generation of the photocurrent indicates their use as photodiodes and the best result was observed for SAI3 : TiO2 complexes. [ABSTRACT FROM AUTHOR]

Depression is one of the major causes of disability worldwide. A proportion of adults with major depression fail to achieve remission with first-line treatment. Magnesium influences the neurotransmission involved in emotional processes, such as the serotonergic, noradrenergic, dopaminergic, GABAergic and glutamatergic systems. It has been reported that the mechanism of antidepressants' action is involved in the glutamatergic system. Theories about the role of magnesium ions in pathophysiology of major depressive disorder include blocking the glutamatergic N-methyl-D-aspartate receptor (NMDAR). Ketamine, NMDAR antagonist, was found to promote fast-acting antidepressant and antisuicidal effects. Magnesium and ketamine seem to be involved in key mechanisms of the major depression pathophysiology. The evidence in the paper discussed may indicate the synergistic interaction between magnesium and ketamine pharmacodynamic activity being of particular importance in mood disorders. [ABSTRACT FROM AUTHOR]

A new piperazine imine, (7E)-N-((4-((E)-(4-hexadecylphenylimino)methyl) piperazin-1-yl)methylene)-4-dodecylbenzenamine, has been synthesized by the condensation of 1,4-piperazinedicarboxaldehyde with 4- hexadecylaniline. The imine was characterized by cyclic voltammetry, Fourier transform middle-infrared absorption spectroscopy and X-ray diffraction. Thermal properties of imine was analyzed by differential scanning calorimetry method during first and second heating scan at 10 and 20 °C/min. Texture of imine was investigated by polarized optical microscopy and atomic force microscopy. Furthermore, imine was blended with titanium dioxide in anatase form and fully characterized by the same methods. Piperazine imine and its mixture with titanium dioxide exhibited only a transition from crystal to isotropic state. Imine exhibits two-step reduction wave attributed to one-electron transfer in each step as was found by cyclic voltammetry. Both titanium dioxide and poly(3-hexylthiophene) change the electrochemical properties of piperazine imine, however, in different ways. Studied imine blended with titanium dioxide exhibited higher value of energy band gap than pure piperazine imine and lower Eg than pure poly(3-hexylthiophene). [ABSTRACT FROM AUTHOR]

Polycrystalline hexakis(urea-O)chromium(III) tetrafluoroborate possesses in the temperature range of 295–105 K one solid–solid phase transition at T C ≈ 255 K. Analysis of the band shapes associated with the ν as (CN) and δ as (NH 2 ) vibrational modes of the Fourier transform infrared absorption (FT-IR) spectra, registered in the temperature range of 295–10 K, indicated existence of fast (τ R ≈ 10 − 12 s) reorientational motion of the protons from NH 2 groups belonging to OC(NH 2 ) 2 (urea) ligands, which does not suddenly change at T C . Moreover, splitting of the IR bands associated with the ν as (NH), ν s (NH) and ν as (BF) F 2 / ν s (CN) modes at T C indicated that this phase transition is associated with a change of crystal structure. Similar analysis of the Raman scattering bands (FT-RS), associated with the δ s (FBF) E , ν s (BF) A and ν as (BF) F 2 / ν s (CN) vibrational modes, indicated fast reorientation of the BF 4 − ions, which does not suddenly change at T C , and additionally confirmed structural character of this phase transition. Results obtained from vibrational spectroscopy measurements are compatible with that obtained by electron paramagnetic resonance spectroscopy (EPR) measurements in function of temperature, where rapid narrowing of the EPR line in the vicinity of the T C was observed. [ABSTRACT FROM AUTHOR]

Three solid–solid phase transitions have been detected for [Sr(OS(CH3)2)4(NO3)2] atT = 229.3 K,T = 220.3 K, andT = 171.6 K (on heating) and atT = 226.6 K,T = 219.1 K, andT = 170.9 K (on cooling). The compound melts atTm≈ 347 K. Thermal behavior of the deuterated analog is essentially the same, but the phase transitions’ temperatures are shifted slightly towards higher temperature, by ca.5, 5, and 15 K, respectively. Crystal structure in the lowest temperature of phase III at 93 K consists of completely ordered (CH3)2SO molecules and bidentate nitrate groups, which are coordinated to strontium cation. Infrared (IR) spectra reveal that the phase transition atTis associated with the slowing down of the reorientational motions of (CH3)2SO and NO3–groups and also with the lowering of crystal lattice symmetry of the compound. The extended solid-state vibrational analysis has been performed for both deuterated and protonated species by solid-state density functional theory computations and compared with IR and RS experimental spectra. Thermal decomposition occurs in two stages: in the first stage, in four steps, four (CH3)2SO molecules are liberated and Sr(NO3)2is formed, and in the second stage, above ca.800 K, SrO is formed. [ABSTRACT FROM PUBLISHER]

Five crystalline phases of [Co(NH3)6](BF4)3 were identified by adiabatic calorimetry. Two phase transitions at Tc1(II→I) = 271.7K and Tc2(111 → II) = 152.2K are accompanied by large entropy changes (8.4 and 6.5 J K1 mol1, respectively), whereas two additional transitions at Tc3(IV → III) = 67.4K and Tc4(V→IV) = 48.9K are accompanied by small entropy changes (0.31 and 0.15 J K-1 mol-1, respectively). X-ray single-crystal diffraction at 293 K demonstrates that phase I is cubic (Z= 4) and that two types of anions exist with different types of orientational disorder. In phase II, at 200 K, which is also a cubic system (Z=32), five anions (out of 12) become ordered, and three cations (out of four) are deformed to give a lower symmetry. This is attributed to the orientational ordering of the anions triggered by NH-F hydrogen-bonding interactions. Further ordering of the anions and the symmetry reduction of the crystal occurred at Tc2, but the structure of phase III still remained cubic. The energies required to reorient an ordered anion in the crystal lattice of phases II and III were estimated from the excess heat capacity, demonstrating that the NH... F hydrogen-bonding interactions in this compound are considerably weaker than the NH...O interactions in an isostructural compound, [Co(NH3)6](ClO4)3. [ABSTRACT FROM AUTHOR]

Five crystalline phases of [Co(NH3)6](BF4)3 were identified by adiabatic calorimetry. Two phase transitions at Tc1(II→I) = 271.7K and Tc2(111 → II) = 152.2K are accompanied by large entropy changes (8.4 and 6.5 J K1 mol1, respectively), whereas two additional transitions at Tc3(IV → III) = 67.4K and Tc4(V→IV) = 48.9K are accompanied by small entropy changes (0.31 and 0.15 J K-1 mol-1, respectively). X-ray single-crystal diffraction at 293 K demonstrates that phase I is cubic (Z= 4) and that two types of anions exist with different types of orientational disorder. In phase II, at 200 K, which is also a cubic system (Z=32), five anions (out of 12) become ordered, and three cations (out of four) are deformed to give a lower symmetry. This is attributed to the orientational ordering of the anions triggered by NH-F hydrogen-bonding interactions. Further ordering of the anions and the symmetry reduction of the crystal occurred at Tc2, but the structure of phase III still remained cubic. The energies required to reorient an ordered anion in the crystal lattice of phases II and III were estimated from the excess heat capacity, demonstrating that the NH... F hydrogen-bonding interactions in this compound are considerably weaker than the NH...O interactions in an isostructural compound, [Co(NH3)6](ClO4)3. [ABSTRACT FROM AUTHOR]

Abstract: [Co(NH3)6](ClO4)3 was investigated by neutron scattering methods in the temperature range of 20–290K. Neutron powder diffraction revealed that the crystal structure does not change at the T C2 and T C3 phase transitions. High temperature phases are orientationally disordered. QENS study showed that NH3 ligands perform rapid reorientational motion around their 3-fold axes in a wide temperature range. However, below T C3 some excess of elastic scattering is observed, which can be explained by the assumption that only half of the NH3 groups reorient fast enough to contribute to the QENS broadening, whereas the remaining NH3 groups reorient more slowly. The activation energy for NH3 jumps, estimated from the temperature dependence of QENS broadening, is small but comparable with the results obtained for other hexaammine complexes. Quantum chemical calculation, carried out on the basis of DFT for isolated [Co(NH3)6]3+ cation and anion, and experimental (IR,RS,IINS) spectra are in good agreement. [Copyright &y& Elsevier]

Abstract: Two phase transitions – one sharp at T 1 =247.4K and the other very broad at T 2 ∼135K – were observed for [Cr(OS(CH3)2)6](BF4)3 by adiabatic calorimetry. They are of the order–disorder type, and their transition entropies are 28.4 and 8.3JK−1 mol−1, respectively. IR absorption and Raman scattering spectroscopy measurements revealed distinct changes in the molecular dynamics of both CH3 groups and BF4 − anions at T 1 and reduced symmetry of the [Cr(OS(CH3)2)6]3+ complex cations and OS(CH3)2 ligands below T 2. The spectral width of an IR and Raman active band associated with the δ as(FBF)F 2 mode yielded an activation energy (E a)∼9kJmol−1 for the reorientation of BF4 − anions, which is comparable with that obtained for other coordination compounds with BF4 − anions. [Copyright &y& Elsevier]

Abstract: Two phase transitions were found in solid [Al(OS(CH3)2)6](NO3)3 at T C1 =343.1K by differential scanning calorimetry and at T C2 =34.3K by adiabatic calorimetry. The transition at T C1 is accompanied by large thermal hysteresis (ca. 30K) and a large entropy change (76JK−1 mol−1), suggesting an order–disorder-type transition, whereas that at T C2 has a considerably smaller entropy change (3.4JK−1 mol−1). The phase behavior of the deuterated compound is essentially the same. IR and Raman spectra reveal a reduction in symmetry below T C1 and a change in the reorientational dynamics of CH3 groups and NO3 − anions, indicating that the highest temperature phase is orientationally disordered. The transition at T C2 can be explained by a librational soft-mode theory and all complex cations change their orientation in a cooperative manner. [Copyright &y& Elsevier]

The aim of our study was to analyze the influence of various concentrations of γ-Fe2O3 nanoparticles on the physical properties of the liquid crystalline ferroelectric SmC* phase, as well as to check the effect of introducing nanoparticles in the LC matrix on their properties in the prepared five nanocomposites. UV-vis spectroscopy showed that the admixture reduced the absorption of nanocomposites in the UV range, additional absorption bands appeared, and all nanocomposites were transparent in the range of 500–850 nm. The molecular dynamics in particular phases of the nanocomposites were investigated by the dielectric spectroscopy method, and it was found that nanoparticles caused a significant increase in the dielectric constant at low frequencies, a strong modification of the dielectric processes in the SmC* phase, and the emergence of new relaxation processes for the highest dopant concentrations. SQUID magnetometry allowed us to determine the magnetic nature of the nanoparticles used, and to show that the blocked state of nanoparticles was preserved in nanocomposites (hysteresis loops were also registered in the ferroelectric SmC* phase). The dependence of the coercive field on the admixture concentration and the widening of the hysteresis loop in nanocomposites in relation to pure nanoparticles were also found. In turn, the FT-MIR spectroscopy method was used to check the influence of the impurity concentration on the formation/disappearance or modification of the absorption bands, and the modification of both the FWHM and the maximum positions for the four selected vibrations in the MIR range, as well as the discontinuous behavior of these parameters at the phase transitions, were found. [ABSTRACT FROM AUTHOR]

The aim of this paper is to show, by systematic studies, the influence of γ-Fe2O3 nanoparticles on the physical parameters of the liquid crystalline matrix, exhibiting a ferroelectric phase in a wide temperature range. The detailed research was carried out by using diffraction (PXRD), microscopic (OM, SEM, FCPM, POM), thermal (DSC), optical (TLI), electric and spectroscopic (FTIR) methods. We show that even the smallest concentration of γ-Fe2O3 nanoparticles largely modifies the parameters of the ferroelectric SmC* phase, such as spontaneous polarization, switching time, tilt angle, rotational viscosity, dispersion anchoring energy coefficient and helix pitch. The admixture also causes a significant reduction in the temperature of phase transitions, broadening the SmA* phase at the expense of the SmC* phase and strong streaking of the texture. We present and explain the non-monotonic modification of these parameters with an increase in the nanoparticle concentration. The influence of oleic acid admixture on these parameters is also widely discussed. We have shown that certain parameters of organic-metal nanocomposites can be controlled by the appropriate amount of metal admixture. [ABSTRACT FROM AUTHOR]

Relationship between depression and magnesium levels is reported. This observational study examined whether serum magnesium concentration change over time of ketamine treatment course, also whether association between magnesium concentrations and treatment response measured with Montgomery-Åsberg Depression Rating Scale (MADRS) score occurs. Moreover, interlink between changes in Young Mania Rating Scale (YMRS) score, somatic comorbidities, and magnesium concentration was studied. Inpatients with major depressive disorder or bipolar disorder were rated weekly by clinician using MADRS and YMRS. Magnesium levels assessments were carried out weekly, before start of ketamine treatment and then every second infusion and one week after last ketamine infusion. The concentration of Mg2+ ions differs depending on the measurement. The Mg2+ concentration in pre-measurement was significantly higher than in measurement after five infusions (p = 0.031) and after seven infusions (p = 0.003). No significant correlation was observed between changes in magnesium serum levels and MADRS or YMRS. The concentration of Mg2+ ion in course of the treatment was not associated with somatic comorbidities. The study supports data for role of magnesium in treatment-resistant depression, particularly related to ketamine treatment, but provides no clear evidence of straightforward association between magnesium serum concentration and treatment response or comorbidity. [ABSTRACT FROM AUTHOR]

The main goal of this paper was to study the dielectric properties of hybrid binary and ternary composites based on biodegradable polymer Ecoflex®, single walled carbon nanotubes (SWCN), and liquid crystalline 4′-pentyl-4-biphenylcarbonitrile (5CB) compound. The obtained results were compared with other created analogically to Ecoflex®, hybrid layers based on biodegradable polymers such as L,D-polylactide (L,D-PLA) and polycaprolactone (PCL). Frequency domain dielectric spectroscopy (FDDS) results were analyzed taking into consideration the amount of SWCN, frequency, and temperature. For pure Ecoflex®, two relaxation processes (α and β) were identified. It was shown that the SWCN admixture (in the weight ratio 10:0.01) did not change the properties of the Ecoflex® layer, while in the case of PCL and L,D-PLA, the layers became conductive. The dielectric constant increased with an increase in the content of SWCN in the Ecoflex® matrix and the conductive behavior was not visible, even for the greatest concentration (10:0.06 weight ratio). In the case of the Ecoflex® polymer matrix, the conduction relaxation process at a frequency ca. several kilohertz appeared and became stronger with an increase in the SWCN admixture in the matrix. Addition of oleic acid to the polymer matrix had a smaller effect on the increase in the dielectric response than the addition of liquid crystal 5CB. Fourier transform infrared (FTIR) results revealed that the molecular structure and chemical character of the Ecoflex® and PCL matrixes remained unchanged upon the addition of SWCN or 5CB in a weight ratio of 10:0.01 and 10:1, respectively, while molecular interactions appeared between L,D-PLA and 5CB. Moreover, adding oleic acid to pure Ecoflex® as well as the binary and ternary hybrid layers with SWCN and/or 5CB in a weight ratio of Ecoflex®:oleic acid equal to 10:0.3 did not have an influence on the chemical bonding of these materials. [ABSTRACT FROM AUTHOR]

Although Poland is one of the leading recipients of the waste stream in the European Union (EU), it is at the same time below the average in terms of efficiency of their use/utilization. The adopted technological solutions cause waste processing rates to be relatively low in Poland. As a result, the report of the Early Warning and Response System (EWRS) of the EU indicated Poland as one of the 14 countries of the EU which are at risk in terms of possibility of achieving 50% recycling of waste. This article discusses the implemented technological solutions, and shows the profitability of the investment and the values of the process heat demand both for extractor and reactor. The experimental part analyzed the composition of the input and output of the process and compared it to the required fuel specifications. Attention was drawn to the need to improve the recycling process in order to increase the quality of manufactured fuel components. As potential ways of solving the problem of low fuel quality, cleaning the sorted reaction mass from solid particles and extending the technological line with a distillation column have been proposed. The recommended direction of improvement of the technology is also the optimization of the process of the reactor's purification and removal of contaminants. [ABSTRACT FROM AUTHOR]

Changes in serum copper concentration are observed in patients with depressive symptoms. Unmet needs in contemporary antidepressant treatment have increased interest in non-monoaminergic antidepressants, such as ketamine, an anaesthetic drug that has demonstrated a rapid antidepressant effect in patients with treatment-resistant depression (TRD). The purpose of this study was to examine whether serum copper concentrations change during ketamine treatment and whether there is an association between the copper concentrations and treatment response measured using psychometric scale scores. Moreover, the interlink between somatic comorbidities and copper concentration was studied. Patients with major depressive disorder or bipolar disorder were rated weekly by a clinician using the Montgomery–Asberg Depression Rating Scale (MADRS) and Young Mania Rating Scale (YMRS). Copper level assessments were carried out weekly before the start of ketamine treatment and then after every second infusion and one week after the last ketamine infusion. The serum concentration of copper before ketamine treatment was significantly higher than that after the fifth infusion (p = 0.016), and the serum concentration after the treatment was significantly higher than that after the fifth infusion (p = 0.048). No significant correlations between changes in the copper serum concentrations and MADRS or YMRS were found. The serum copper level was not associated with somatic comorbidities during the course of treatment. This study provides data on the role of copper in short-term intravenous ketamine treatment in TRD, although no clear evidence of a connection between the copper level and treatment response was found. [ABSTRACT FROM AUTHOR]

Treatment-resistant depression (TRD) remains one of the major psychiatric challenges worldwide. Search for non-monoaminergic agents, possibly effective in treatment of TRD is of prime importance. One of those agents is ketamine - a dissociative, anesthetic drug exhibiting a fast antidepressant action in patients with TRD. Concurrently, anhedonia appears to be significant symptom domain with far-reaching impact on course of treatment. There is data demonstrating that abnormal copper levels might be associated with symptoms of depression. As there is common denominator in ketamine and copper role in neurotransmission this paper is to explore the associations of blood copper levels and psychometric measures in patients with TRD in course of major depressive disorder (MDD) and bipolar disorder (BP), focusing on anhedonia measured with Snaith-Hamilton Pleasure Scale (SHAPS) score. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrids based on liquid crystalline symmetrical imine (8Z)-N-(4-((Z)-(4-pentylphenylimino)methyl)benzylidene)-4-pentylbenzenamine (AZJ1) with two aliphatic chains and TiO2 nanomaterials were obtained and investigated taking into account thr crystallographic form of titanium dioxide i.e., anatase versus rutile. The type of TiO2 influences the mesomorphic properties of imine AZJ1, as observed by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) techniques. Fourier-Transform Infrared Spectroscopy (FT-IR) was used to investigate the interactions of oxygen vacancies located on the TiO2 surface with the studied AZJ1 imine together with studying the influence of temperature. Both imine:TiO2 anatase versus rutile hybrids possessed the highest occupied molecular orbital (HOMO) levels of about −5.39 eV (AZJ1:anatase) and −5.33 eV (AZJ1:rutile) and the lowest unoccupied molecular orbital (LUMO) levels of about −2.24 eV. The presence of TiO2 in each hybrid did not strongly affect the redox properties of imine AZJ1. Organic devices with the configuration of ITO/TiO2/AZJ1 (or AZJ1:TiO2 anatase versus rutile)/Au were fabricated and investigated in the presence and absence of visible light irradiation with a light intensity of 93 mW/cm2. Finally, to analyze defects in the constructed organic devices we used thermal imaging and atomic force microscopy (AFM). The addition of TiO2 in both crystallographic forms has a positive influence on layer-forming properties that manifests itself as a very homogenous heat distribution for the whole sample. [ABSTRACT FROM AUTHOR]

We report on the application of l,d-poly(lactic acid) (l,d-PLA) with dispersed Single-Walled Carbon Nanotubes (SWCN) as a flexible translucent electrode for organic devices. We used commercially available nanotubes in various weight ratios from 0 to 8% dispersed in chloroform polymeric solution by ultrasonication and were drop cast. The created hybrid materials were investigated by differential scanning calorimetry to determine the influence of SWCN content on the thermal behavior, while polarizing optical microscope was used to find the effect of mechanical deformations on the textures. Drop-cast films were studied by optical transmittance, conductivity, dielectric properties and by thermal imaging under applied potential. Thermal imaging provided evidence of visible voltage-activated conduction. Simple mechanical deformation such as bending with stretching at edge to ca. 90 and elongation test were performed. Moreover, interactions between l,d-poly(lactic acid) and SWCN were investigated by FT-IR and NMR spectroscopy. Finally, we can conclude that the thermographic examination of created films permits fast, simple and inexpensive localization of defects on the surface of l,d-PLA:SWCN film, together with the electrical properties of the films. [ABSTRACT FROM AUTHOR]

[Ni(ND3)6](ClO4)2 has three solid phases between 100 and 300 K. The phase transitions temperatures at heating (TC1h=164.1 K and TC2h=145.1 K) are shifted, as compared to the non-deuterated compound, towards the lower temperature of ca. 8 and 5 K, respectively. The ClO4- anions perform fast, picosecond, isotropic reorientation with the activation energy of 6.6 kJ mol-1, which abruptly slow down at TC1c phase transition, during sample cooling. The ND3 ligands perform fast uniaxial reorientation around the Ni–N bond in all three detected phases, with the effective activation energy of 2.9 kJ mol-1. The reorientational motion of ND3 is only slightly distorted at the TC1 phase transition due to the dynamical orientational order–disorder process of anions. The low value of the activation energy for the ND3 reorientation suggests that this reorientation undergoes the translation–rotation coupling, which makes the barrier to the rotation of the ammonia ligands not constant but fluctuating. The phase polymorphism and the dynamics of the molecular reorientations of the title compound are similar but not quite identical with these of the [Ni(NH3)6](ClO4)2. [Copyright &y& Elsevier]

Abstract: Four crystalline phases of the coordination compound [Ru(NH3)6](BF4)3 are identified by adiabatic calorimetry. Three phase transitions, one at T C3(IV→III)=30.7K, the second at T C2(III→II)=91.7K (both accompanied by comparable entropy changes 3.0 and 3.1JK−1 mol−1, respectively) and the third at T C1(II→I)=241.6K (accompanied by an entropy change of 8.1JK−1 mol−1) were discovered. X-ray single crystal diffraction (at 293K) demonstrates that phase I is a highly dynamic disordered cubic phase (, No. 225) with two types of anions differing in a degree of disorder. In phase II (at 170K) the structure remains cubic (, No. 206), with two different types of cations and four different types of anions. Splitting of certain IR bands connected with NH3 ligands at the observed phase transitions suggests a lowering of the symmetry of the [Ru(NH3)6]3+ complex cation. Both NH3 ligands and anions perform fast reorientations (τ R ≈10−12 s), which are significantly slowed down below the phase transition at T C3. 1H NMR studies led to estimate the values of the activation energy of NH3 ligands reorientation in the phases II and I as equal to ∼8kJmol−1. In phase I the whole hexammineruthenium(III) cations reorientation as a tumbling process can be noticed. The activation energy value of this motion is ∼24kJmol−1. 19F NMR studies give the values of the activation energy of anions reorientation as ∼6kJmol−1. Above the phase transition temperature half of anions perform a tumbling motion with E a ≈8kJmol−1. [Copyright &y& Elsevier]