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The technique has been developed for the quantification of small tantalum, cesium, barium, lanthanum, cerium, and neodymium concentration in rocks with X-ray wavelength dispersive spectrometer S8 TIGER (Bruker AXS, Germany). The optimum conditions have been chosen for registration of the analyzed elements characteristic radiation and background positions. To determine the concentrations of analyzed elements accurately, the contribution of overlapping lines to the experimental intensities of the analytical lines has been taken into account. The sample of mass about 1.2 g has been pressed into pellet by the hydraulic press. Metrological studies showed that the accuracy in the determination of the concentration of analyzed elements for the developed technique meets the requirements for methods of III accuracy class. The Ta detection limits calculated for TaLβ1-analytical and CsLα1-analytical lines were 2.6 and 3.4 ppm, respectively. The detection limit of Ba, La, Ce, and Nd was (in ppm), respectively, 4.3, 2.7, 5.8, and 4.7. The metrological characteristics of the previously developed and adapted techniques were compared. Ta concentration in granite pegmatite samples has been quantified. The samples of the highest tantalum content have been investigated additionally by powder diffraction and X-ray microprobe analysis. The X-ray diffraction method turned out to be insensitive to the detection of mineral phase of tantalum niobates, while micro-XRF allowed detecting its presence in tourmaline grains. Copyright © 2017 John Wiley & Sons, Ltd.

Objective\ud We aimed to characterize the demographics of adults with dissociative (nonepileptic) seizures, placing emphasis on distribution of age at onset, male:female ratio, levels of deprivation, and dissociative seizure semiology.\ud \ud Methods\ud We collected demographic and clinical data from 698 adults with dissociative seizures recruited to the screening phase of the CODES (Cognitive Behavioural Therapy vs Standardised Medical Care for Adults With Dissociative Non‐Epileptic Seizures) trial from 27 neurology/specialist epilepsy clinics in the UK. We described the cohort in terms of age, age at onset of dissociative seizures, duration of seizure disorder, level of socioeconomic deprivation, and other social and clinical demographic characteristics and their associations.\ud \ud Results\ud In what is, to date, the largest study of adults with dissociative seizures, the overall modal age at dissociative seizure onset was 19 years; median age at onset was 28 years. Although 74% of the sample was female, importantly the male:female ratio varied with age at onset, with 77% of female but only 59% of male participants developing dissociative seizures by the age of 40 years. The frequency of self‐reported previous epilepsy was 27%; nearly half of these epilepsy diagnoses were retrospectively considered erroneous by clinicians. Patients with predominantly hyperkinetic dissociative seizures had a shorter disorder duration prior to diagnosis in this study than patients with hypokinetic seizures (P < .001); dissociative seizure type was not associated with gender. Predominantly hyperkinetic seizures were most commonly seen in patients with symptom onset in their late teens. Thirty percent of the sample reported taking antiepileptic drugs; this was more common in men. More than 50% of the sample lived in areas characterized by the highest levels of deprivation, and more than two‐thirds were unemployed.\ud \ud Significance\ud Females with dissociative seizures were more common at all ages, whereas the proportion of males increased with age at onset. This disorder was associated with socioeconomic deprivation. Those with hypokinetic dissociative seizures may be at risk for delayed diagnosis and treatment.

Increasing global challenges such as climate change, environmental pollution, and energy shortage have stimulated the worldwide explorations into novel and clean materials for their applications in the capture of carbon dioxide, a major greenhouse gas, and toxic pollutants, energy conversion, and storage. In this study, two microstructured carbons, namely N-doped pillaring layered carbon (NC) and N, S codoped honeycomb carbon (NSC), have been fabricated through a one-pot pyrolysis process of a mixture containing glucose, sodium bicarbonate, and urea or thiourea. The heteroatom doping is found to induce tailored microstructures featuring highly interconnected pore frameworks, high sp2-C ratios, and high surface areas. The formation mechanism of the varying pore frameworks is believed to be hydrogen-bond interactions. NSC displays a similar CO2 adsorption capacity (4.7 mmol g−1 at 0 °C), a better CO2/N2 selectivity, and higher activity in oxygen reduction reaction as compared with NC-3 (the NC sample with the highest N content of 7.3%). NSC favors an efficient four-electron reduction pathway and presents better methanol tolerance than Pt/C in alkaline media. The porous carbons also exhibit excellent rate performance as supercapacitors.

Preparation of composites with different properties and gradient of components is aimed at better performance of materials for bone substitution. Bacterial cellulose-hydroxyapatite (BC-HAP) composites with various mass ratio of the components (BC-25HAP, BC-4HAP, and BC-HAP) were prepared by a novel method of growing HAP nanocrystals (the linear size ≤30 nm) in water solutions in the presence of the BC gel-film micro-fragments. Varying the BC-HAP ratios leads to a gradual change of the physical properties of the materials. It was found that an increase in the BC content results in a decrease of the HAP crystal length and specific surface area, porosity, and pore volume while the values of density and Young's modulus values increase. SCANNING 38:757-765, 2016. © 2016 Wiley Periodicals, Inc.

This work concerns determination of the manganese valence state and speciation by wavelength-dispersive X-ray fluorescence analysis. The authors investigated the effect of the manganese valence state and speciation on the intensity of some К-series lines of the X-ray emission spectrum for the samples of manganese compounds. The intensities of MnKβ5 line and MnKβ′ satellite are least influenced by speciation, and they may be used for evaluating the manganese valence state for the samples containing low iron. The intensities of MnKβ″ and MnKβx satellites may be employed for assessing the manganese speciation. The results of X-ray fluorescence determination of the manganese valence state and speciation in the manganese ores of the South Ural deposits agree with the X-ray diffraction data. The X-ray fluorescence method is definitely advantageous, because it does not require a complicated process of sample preparation and allows to receive fast information on the manganese valence state and speciation with the purpose to assess the quality of manganese ores. Copyright © 2015 John Wiley & Sons, Ltd.

Molecular surfactants are widely used to control low-dimensional morphologies, including 2D nanomaterials in colloidal chemical synthesis, but it is still highly challenging to accurately control single-layer growth for 2D materials. A scalable stacking-hinderable strategy to not only enable exclusive single-layer growth mode for transition metal dichalcogenides (TMDs) selectively sandwiched by surfactant molecules but also retain sandwiched single-layer TMDs' photoredox activities is developed. The single-layer growth mechanism is well explained by theoretical calculation. Three types of single-layer TMDs, including MoS2 , WS2 , and ReS2 , are successfully synthesized and demonstrated in solar H2 fuel production from hydrogen-stored liquid carrier-methanol. Such H2 fuel production from single-layer MoS2 nanosheets is COx -free and reliably workable under room temperature and normal pressure with the generation rate reaching ≈617 µmole g-1 h-1 and excellent photoredox endurability. This strategy opens up the feasible avenue to develop methanol-storable solar H2 fuel with facile chemical rebonding actualized by 2D single-layer photocatalysts.

K7.814Sm3Si12O32 (OH)0.814·0.77H2O (I), K7.04Tb3Si12O32.02 ·1.36H2O (II), K2GdAlSi4O12·0.25H2O (III), K2SmAlSi4O12·0.375H2O (IV), and K4Yb2Si8O21 (V) are hydrothermally synthesized from aqueous mixtures of Ln2O3 (Ln: Yb, Sm, Tb, Gd), SiO2, Al2O3, and KOH (autoclave equipped with either copper or nickel containers, 500 °C, 30 d).

Apicomplexa division involves several distinct phases shared with other eukaryote cell cycles including a gap period (G1) prior to chromosome synthesis, although how progression through the parasite cell cycle is controlled is not understood. Here we describe a cell cycle mutant that reversibly arrests in the G1 phase. The defect in this mutant was mapped by genetic complementation to a gene encoding a novel AAA-ATPase/CDC48 family member called TgNoAP1. TgNoAP1 is tightly regulated and expressed in the nucleolus during the G1/S phases. A tyrosine to a cysteine change upstream of the second AAA+ domain in the temperature sensitive TgNoAP1 allele leads to conditional protein instability, which is responsible for rapid cell cycle arrest and a primary defect in 28S rRNA processing as confirmed by knock-in of the mutation back into the parent genome. The interaction of TgNoAP1 with factors of the snoRNP and R2TP complexes indicates this protein has a role in pre-rRNA processing. This is a novel role for a cdc48-related chaperone protein and indicates that TgNoAP1 may be part of a dynamic mechanism that senses the health of the parasite protein machinery at the initial steps of ribosome biogenesis and conveys that information to the parasite cell cycle checkpoint controls.

This study presents a dipcasting method that can deposit both porous and dense bioceramic coatings onto 3D Ti-mesh made from commercially pure Ti-mesh for surgical applications. First, a dense bioglass coating was deposited onto the 3D Ti-mesh, which is to seal off the Ti-mesh. Second, a microporous HA/bioglass coating was deposited on top of the dense bioglass coating, which is to promote bone regeneration into the 3D Ti-mesh. X-ray diffraction, field emission scanning electron microscopy, and energy dispersive X-ray spectroscopy were used to analyze the bioceramic coatings and cross-sectional microstructures. Vickers microhardness across the interface between bioceramic coating and Ti-substrate was measured.

The effect of irradiation with heavy ions 40Ar8+ (48MeV), 132Xe27+ (167MeV) and 84Kr17+ (107 MeV) on the critical temperature (Tc) and critical current (Ic) of YBCO(123) composite tapes was investigated. It was found that threshold values were 5 × 1012 and 1 × 1013 ion/cm2 for 132Xe27+ and 84Kr17+ irradiation, correspondently. Critical current measured at T = 77 K increased for the lower 40Ar8+ and 84Kr17+ fluencies compared to the initial values. The formation of radiation defects that could be effective pinning centers of Abrikosov vortices resulted in the increase of the critical current. The calculations of track diameters produced by 84Kr17+ ions with energy 1.2 MeV/amu in the composite YBCO tape showed the good agreement with the experimental ones. Transmission electron microscopy (TEM), high resolution TEM and scanning TEM were used to study defects induced by irradiation. The diameter of defects obtained from TEM was in the range from 3 to 5 nm. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Manipulating the properties of well understood materials systems for novel technological applications can be achieved by creating nanoscale structures and mixed compounds. The design of novel nanomaterials that underpin plasmonic applications drives the rapid progress in advancing plasmonic materials over the last few years. [ 1 , 2 ] Control of metal nanoparticle shape, [ 3 , 4 ] density, and spacing [ 5 ] is continually improving with novel synthetic techniques. Nevertheless, to continue advancing plasmonics, new metallic nanostructure systems must be developed that offer unique properties and are superior to Ag, [ 6 ] Au, [ 3 , 7 ] and mixtures thereof—the most widely exploited metals [ 8–10 ] and bimetallic systems. [ 11 ]

A dinuclear naphthalocyanine analogue containing two incomplete naphthalocyanine macrocycles connected by a shared benzene ring was synthesized in good yield. The long-wavelength absorption band in the electronic spectrum is observed at λ = 965 nm. As a consequence of the π-system extension caused by dimerization and addition of further peripheral benzene rings, this band is shifted bathochromically by approximately 300 nm compared to absorption bands of mononuclear phthalocyanines.

Photonic crystal (PC) structures have emerged as perhaps the ultimate platform for microdevices that can manipulate light in all three dimensions. PCs represent a major new frontier for a diverse set of properties including their ability to coherently manipulate light. It has been predicted that a weakly penetrating etched photonic lattice on the surface of a light-emitting diode (LED) can suppress all lateral modes, causing the light to be emitted primarily in the vertical direction. PCs have been restricted to a subset of materials that can be formed in the sol-gel processing. It is not possible to make PCs from just any material, which limits their potential properties. Coating is one way to add functionality, but traditional techniques such as physical vapor deposition (PVD) and chemical vapor deposition (CVD) cannot coat the complex porous structures. Sol-gel can penetrate the pores but does not result in conformal coatings since metal oxide oligomers form in the bulk solution. The primary technique used for effective coating of 3D materials such as inverse opal structures is atomic layer deposition (ALD). ALD applies one atomic layer at a time though a process that makes use of reagents that can chemically react only with the surface (not with themselves). ALD is limited in that thicker coatings require many steps and only single component coatings can be readily applied. Herein we demonstrate the ability of a relatively new polymer-assisted deposition technique (PAD) to deposit conformal coatings of complex metal oxides on nanostructured 3D supports by coating a benchmark phosphor onto a commercially supplied nanostructure. Yttrium orthovanadate (YVO4) is an excellent polarizer and laser host material in its single-crystal form. Europium doping

Ligand-oxidized annulated dinuclear phthalocyanine zinc(II) and lithium(I) complexes absorbing in the NIR region (l = 1000-2200 nm) with high extinction coefficients are de- scribed. Analogous mononuclear Pc complexes were used for comparison. The oxidized Pcs were characterized in solution by electronic absorption, EPR and NMR spectra. The NIR transitions were explained by using MO diagrams calculated semiempirically. The reversi- ble oxidation behavior of the phthalo- cyanine complexes was also estimated by cyclic voltammetry. These new ex- tremely long wavelength absorbing phthalocyanines are interesting as ma- terials with new electronic properties.

Isomeric linear and rectangular trinuclear metal-free andzinc(II) phthalocyanine complexes connected by common annulated benzene rings have been synthesized by the mixed cyclotetramerization of a 1,2,4,5-tetracyanobenzene derivative and 4,5-bis(2,6-dimethylphenoxy)phthalonitrile. Their electronic-absorption and fluorescence spectra have been studied in comparison with the corresponding mono- and dinuclear phthalocyanines. For the zinc complexes, the molecular orbitals and electronic spectra have been calculated semi-empirically. The trinuclear phthalocyanines exhibit absorptions up to 940 nm with extinction coefficients up to about 700000 M–1 cm–1, which shows the extension of the π-electron system.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Gibbs energy, enthalpy, and entropy of mixing in binary blends of chitosan with ter-copolyamide 6/66/610 at ambient conditions have been determined over the entire concentration range using thermodynamic cycle based on dissolution of individual polymers and their blends of different composition in a common solvent -formic acid. Experimental procedure included stepwise equilibrium vapor sorption of glacial formic acid on the cast films and isothermal microcalorimetry of dissolution of these films in liquid glacial formic acid at 25 °C. Formic acid appeared to be a very good solvent for individual polymers and their blends. Flory-Huggins interaction parameter determined from sorption isotherms was negative and varied from -2.56 to -1.79 depending upon blend composition. The enthalpies of dissolution of individual polymers and their blends were strongly exothermic and varied from -200 to -40 Joule/g. Independent thermodynamic cycles for Gibbs free energy and enthalpy remarkably revealed similar trends in concentration dependence of different thermodynamic functions of mixing between chitosan and copolyamide. At high chitosan content, the binary blend is characterized by large and negative values of Gibbs free energy, enthalpy, and entropy of mixing that provide high polymer compatibility. On the contrary, at high copolyamide content the blends are incompatible and are characterized by positive values of enthalpy, entropy, and Gibbs free energy of mixing. Such complicated thermodynamic behavior is the result of the superposition of strong molecular interactions (H-bonds) between polymers in the blend and isothermal fusion of copolyamide crystallites. Thermodynamic analysis correlates well with the fusion of copolyamide crystallites. Thermodynamic analysis correlates well with the data obtained by polarized microscopy.

A comparative characterization of the structure of normal and abnormal (osteoporotic) human lumbar and thoracic vertebrae samples was carried out to reveal the type of possible disorder. Samples from the bone fragments extracted during the surgery due to vertebra fractures were examined by scanning electron microscopy (SEM), conventional and high resolution transmission electron microscopy (TEM and HRTEM), and X-ray energy dispersive spectroscopy (EDS). Contrary to what might be expected in accordance with possible processes of dissolution, formation and remineralization of hard tissues, no changes in phase composition of mineral part, crystal sizes (length, width, and thickness), and arrangement of crystals on collagen fibers were detected in abnormal bones compared to the normal ones. The following sizes were determined by HRTEM for all bone samples

Two chemoattractant receptors, C5aR (the complement fragment C5a receptor) and FPR (the N-formyl peptide receptor), are involved in neutrophil activation at sites of inflammation. In this study, we found major differences in the intracellular trafficking of the receptors in transfected Chinese hamster ovary (CHO) cells. Western blot analysis showed that FPR was stable during a 3 h stimulation with ligand, but C5aR was reduced in quantity by 50%. Not all C5aR was targeted directly for degradation however; a small, but visible fraction of the receptor became re-phosphorylated upon subsequent addition of ligand, suggesting that some of the receptor had cycled to the cell surface. Light membrane fractions isolated from activated cells showed C5aR distribution at the bottom of a glycerol gradient, colocalizing with the main distribution of the late endosomal/lysosomal marker LAMP2, whereas FPR was found at the bottom of the gradient as well as in the middle of the gradient, where it cofractionated with the early/sorting endosomal marker Rab5. Using fluorescence microscopy, we observed ligand-dependent redistribution of C5aR-EGFP from the plasma membrane to LAMP2-positive compartments, whereas FPR-EGFP showed significant colocalization with the early/sorting endosomes. Analysis of endogenous C5aR and FPR in neutrophils revealed a pattern similar to the CHO transfectants: C5aR underwent degradation after prolonged ligand stimulation, while FPR did not. Finally, we confirmed the down-regulation of C5aR in a functional assay by showing reduced chemotaxis toward C5a in both CHO transfectants and neutrophils after preincubation with C5a. A similar decrease in FPR-mediated chemotaxis was not observed.

Based on a very recently published monograph a short overview on macromolecular metal complexes (metal complexes and metals in macromolecules) is given. The understanding of biological system is fundamentally important to construct artificial macromolecular metal complexes. A classification for the various up to now synthesized systems is given, and properties and potential applications are pointed out.

Compatibility of PVC with liquid alkyltin alkylthioglycolate stabilizers was studied by thermal methods, including isothermal calorimetry of mixing, DSC, DMA, and dielectric relaxation. The enthalpy of mixing of PVC with the series of alkyltin alkyl thioglycolates was measured over the entire concentration range at ambient conditions. It was found that all tested compounds are compatible with PVC in a broad concentration range and form homogeneous mixtures. The results are discussed in terms of the superposition of glassy state and molecular interaction contributions to the enthalpy of mixing of the glassy polymer with liquid additives. The influence of organotin stabilizers on the glassy structure of PVC films was studied by means of DSC and the dielectric relaxation spectrum. The enhancement of the glassy structure of PVC by alkyltin alkyl thioglycolates is interpreted as the result of strong multi-site molecular complexes between organotin molecules and PVC chains, which act as additional clips in the entanglement network of polymer chains.

Polymeric phthalocyanines are prepared by polycyclotetramerization of tetracarbonitriles and electropolymerization of amino- or pyrrole-substituted phthalocyanines. The conjugated polymers are characterized by a long wavelength absorption and a high electrical conductivity.

Azo coupling of diazonium salts derived from alkyl (4-aminophenyl)carbamates with ethyl α-methylacetoacetate gave ethyl 5-alkoxycarbonylamino-1H-indole-2-carboxylates. The condensation of aminophenylcarbamates with aromatic aldehydes in ethanol afforded the corresponding Schiff bases. Cyclohexyl {4-[(4-methoxyphenyl)methylidene]aminophenyl}carbamate reacted with chloroacetyl chloride in dioxane in the presence of triethylamine to produce cyclohexyl {4-[3-chloro-2-(4-methoxyphenyl)-4-oxoazetidin-1-yl]phenylcarbamate, and the reaction of benzyl {4-[(4-nitrophenyl)methylidene]aminophenyl}carbamate with sulfanylacetic acid in DMF led to the formation of benzyl {4-[2-(4-nitrophenyl)-4-oxo-1,3-thiazolidin-3-yl]-phenyl}carbamate.

Based on low molecular and macromolecular phthalocyanines as light absorbing compounds different light driven reactions are shortly discussed. These processes include under irradiation with visible light energy transfer in photooxidation reactions and electron transfer in photosensibilisation cells or photovoltaic cells. Catalytic oxidation reactions are also mentioned to compare the different mechanisms of dark and light oxidations.

Compatibility of the components, shear viscosity, sorption properties in liquid and vapor water were determined for the mixture of ternary copolyamides (types 6/66/610 and 6/12/66) and amilose starch. This system was shown to be suitable for creation of biodegradable materials.

Keywords: Bones ; electron diffraction ; high-resolution electron microscopy ; hydroxyapatite ; image processing ; image simulation ; micro- and nanoparticles Reference CIME-ARTICLE-1999-026doi:10.1046/j.1365-2818.1999.00608.x Record created on 2007-02-15, modified on 2017-05-12

Macromolecule metal complexes (MMCs)-the combination between a macromolecule, a metal chelate/complex/ion or cluster - are dominating factors for different functions in living systems, and are becoming more and more important in different sciences and applications as artifical synthesized systems.

In recent years,lakes,including salted,attract the attention of researchers,also when reconstructing last climate changes using the bottom sediments(Solotchina et al.,2008,et al.).In this case the different geochemical

Optical properties of polycarbonate plasticized by pentaerythritol tris(1,1,2,3,3,3-hexafluoropropyl) ether (HFP), diheptadecyl-o-phthalate and pentaerythrityl tetrabenzoate (TBP) have been determined at wavelengths from 300 to 700 nm. X-ray diffraction analysis, which was used to examine the polymer structure, showed that all the plasticized systems were amorphous. HFP and, especially, TBP impeded crystallization of the polymer. Plasticized polycarbonate films remained transparent over long periods of time even if they were heated at a temperature higher than the polymer glass transition temperature. © 2003 Society of Chemical Industry

The phase equilibrium of plasticized polymer systems on the basis of cellulose diacetate and ethylene glycol esters of dibasic aliphatic acids (from oxalic acid to 1,10-decanedicarboxylic acid) was studied and the solubility parameters and the thermodynamic interaction parameters of the components were calculated. It is shown that an increase in molecular weight of the plasticizers leads to a lower miscibility of the components, a fact which is reflected in a regular rise of the upper critical solution temperature (UCST), a tendency of the systems for gelation, a decrease of the solubility parameter of the plasticizer δ1, and a growth of the interaction parameters χH and χ12. The results are discussed in terms of the existing theories for polymer solutions.