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Reinforced electrically conductive polymer composites based on ultra-high molecular weight polyethylene reactor powder and filled with various amounts of carbon black, graphite nanopowder, and multiwalled carbon nanotubes were studied. The composites were obtained via compaction of a mechanical mixture of the filler and the polymer reactor powders. This was followed by uniaxial deformation of the material under homogeneous shear conditions. The resulting composites possessed high tensile strength (up to 200 MPa) and electrical conductivity (up to 10 S/cm). Effects of the filler type and content on the electrical conductivity and mechanical properties of the conductive composites were investigated. Changes in the electrical conductivity of the oriented composite materials during reversible “elongation–compression” cycles along the orientation axis direction were observed. The structure of the reinforced electrically conductive polymer composites was characterized using X-ray diffraction and electron microscopy. POLYM. COMPOS., 2017. © 2017 Society of Plastics Engineers

A novel type of all-natural, biocompatible, and very robust nanoscale free-standing biohybrids are reported. They are obtained by integrating a silk fibroin matrix with functional inorganic nanoplatelets using a spin-assisted layer-by-layer assembly. The organized assembly of the silk fibroin with clay (montmorillonite) nanosheets results in highly transparent nanoscale films with significantly enhanced mechanical properties, including strength, toughness, and elastic modulus, as compared to those for the pristine silk nanomaterials. Moreover, replacing clay nanoplatelets with a highly reflective Langmuir monolayer of densely packed silver nanoplates causes a similar enhancement of the mechanical properties, but in contrast to the materials above, highly reflective, mirror-like, nanoscale flexible films are created. This strategy offers a new perspective for the fabrication of robust all-natural flexible nanocomposites with exceptional mechanical properties important for biomedical applications, such as reinforced tissue engineering. On the other hand, the ability to convert silk-based nanoscale films into mirror-like biocompatible flexible films can be intriguing for prospective photonics and optical exploitation of these nanobiohybrids.

Modification of the IR absorption spectra and photoluminescent properties of nanoporous silicon as a result of its interaction with water solutions is investigated. The effect of air pre-oxidation and the solution pH on the interaction is studied. It is found that the reaction of silicon dissolution dominates at the first stage of water treatment, while the formation of the stoichiometric silicon oxide occurs at the second one. Thereafter, the properties of nanoporous silicon are stabilized. The pre-oxidation extent of the sample is found to determine the stabilization time for its properties and the ultimate photoluminescence (PL) parameters. Variation of the solution pH from 4 to 8.5 affects only the evolution rate of the PL spectra. The modifications of the nanostructured silicon PL spectra are explained within the quantum-size model of luminescence. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We describe a method of preparation of high specific activity tritium-labelled leukotriene (LT) B4 from [5,6,8,9,11,12,14,15-3H] arachidonic acid (AA; 6.66 TBq/mmol) utilizing a LTB4-synthesizing enzyme system from rat basophilic leukemia (RBL-1) cells. It was shown that both cyclooxygenase inhibitor indomethacin and adenosine 5′-triphosphate induced [3H] AA transformation to [3H] LTB4. In optimized conditions up to 15% of total radioactivity of the incubation mixture was present in [3H] LTB4. A separation of [3H] LTB4 from other labelled C20:4 products was achieved by a three-step reverse phase-high-performance liquid chromatography in methanol- and acetonitrile-based solvent systems. [3H] LTB4 was confirmed to be identical to the naturally occurring LTB4 by a radioligand binding assay using a culture of HF1 cells that express a BLT1 receptor. Copyright © 2008 John Wiley & Sons, Ltd.

Different states of water and oxide layer in porous silicon (PS) have been studied by IR spectroscopy method. The water states have been shown to depend on contact conditions between PS and condensed or vaporous forms of water and to determine all the variety of oxidation scenarios. Weakly- and strongly-bonded water states are characterized by different frequencies of stretching bands νOH. Fine structure of absorption bands of oxygen-silicon complexes (Si-O-Si, SiSiXO4–X) has been observed in the IR spectra. We associate it with fractal structure for thin oxide layers. Transition of fractal structure into nearly bulk SiO2 structure (where LO-TO splitting is observed) with oxide layer thickness growth is considered. The oxide layer states are characterised by the intensity ratio of stretching to deformation bands for considered silicon-oxygen complexes. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Several isotopomers of ABT-578 (I, II, III, and IV) were prepared starting from different labeled precursors: [5'-3H]-tetrazole (1), [5'-14C]-tetrazole (2), [40-3H]rapamycin (3), and [2,11,31-3H]rapamycin (4). It was shown that the tritium label at the 40 position of rapamycin is lost during an attempted synthesis of [40-3H]ABT-578 (III). Copyright © 2006 John Wiley & Sons, Ltd.

Synthesis of tritium labelled BIBN 4096 – 1-piperidine-3H-carboxamide, N-[2-[[5-amino-1-[[4-(4-pyridinyl)-1-piperazinyl]carbonyl]pentyl]amino]-1-[(3,5-dibromo-4-hydroxyphenyl)methyl]-2-oxoethyl]-4-(1,4-dihydro-2-oxo-3(2 H)-quinazolinyl)-, [R-(R*,S*)]-, – a h-CGRP-antagonist for the treatment of migraine is described. Selective tritiation of a heterocyclic aromatic fragment in the presence of aromatic ring in a precursor of BIBN4096 was successfully carried out using the solid state catalytic exchange method. Subsequent completion of the synthesis sequence gave the final [3H]BIBN4096 with a specific activity of >170 Ci/mmol. Copyright © 2006 John Wiley & Sons, Ltd.

Various approaches to the synthesis of tritium-labelled BIIL 260 with high specific radioactivity were investigated. Attempts to incorporate tritium directly into BIIL 260 were made by solid-phase isotope exchange with tritium gas and by isotope exchange with tritiated water which yielded a final product with specific activities ranging from 2 to 7 Ci/mmol. However, the solid-phase and liquid-phase dehalogenations of an appropriate synthon fragment of BIIL 260 followed by its subsequent conversion to the final product via chemical synthesis yielded the desired tritium-labelled BIIL 260 with specific activities of 25 or 71 Ci/mmol, depending upon the precursors and methods used in the dehalogenation step. Copyright © 2002 John Wiley & Sons, Ltd.

Tritium labelled arachidonic acid amides with dopamine, serotonin, vanillyl-amine and the ethyleneglycol ester moieties with high specific activity (120 Ci/mmol) and yield (70–90%) were prepared from tritiated arachidonic acid by condensation with the corresponding amines and alcohol via mixed anhydrides or acyl fluorides. The labelled compounds were used for studying their uptake by mouse spleen lymphocytes. From the data obtained it was suggested that arachidonic acid amides permeate the membrane by means of passive diffusion, while transmembrane transport of arachidonoylethyleneglycol seems to be driven by the concentration gradient, maintained by hydrolytic enzymes. The compounds synthesized by the reported methods can also be used in receptor binding studies and in the oxidative metabolism of fatty acids amides and esters. Copyright © 2002 John Wiley & Sons, Ltd.

The reaction conditions for the incorporation of tritium into zaleplon have been investigated. The methods studied were the catalytic isotope exchange reaction with tritium gas and catalytic isotope exchange reaction with tritiated water. The results showed that the latter method was the method of choice giving a compound with a higher specific activity and a better yield. Copyright © 2002 John Wiley & Sons, Ltd.

Title Author(s) Tetramethylammonium Tri-acetoxyborotritide, a Reagent for Hydroxy-directed Ketone Reduction H. Andres Synthesis of Tritium-labeled Nucleosides with Anti-HIV and Anticancer Activity G.V. Sidorov, Yu.B. Zverkov, N.F. Myasoedov, A.R. Cimpoia, A.B. Susan Tritide Reduction of Nucleosides and Carbohydrates M. Saljoughian, H. Morimoto, P.G. Williams, C. Than A New Homogeneous Complex for H/D/T Exchange Labelling R. Salter, T. Moenius. P. Ackermann. M. Studer, A. Morgan, M. Chappelle Synthesis of [26-2H3]Brassinosteroids O.V. Konstantinova, V.A. Khripach, V.N. Zhabinskii, A.P. Antonchick, B. Schneider The Specific Activity Determination and Confirmation of Identity of a Radiolabelled Peptide Using Tandem Mass Spectrometry A.T. Rees, A. Colebrook Different Carbon-14 Labelling Syntheses of Vardenafil D. Seidel Carbon-14 Labelling of β-Amino Acids and β-Peptides M.I. Rodriguez, Y. Metz, R. Voges A Rapid Synthesis of 2-Chioro[2,6-144C]isonicotinic Acid T.P. Kelly, T.R. Rodgers, C. Wright Reduction of 2,4,6-Trinitro[ring-14C]toluene (TNT) with Baker's Yeast (Saccharomyces Cervisiae) M. Kroger, G. Fels Application of Microbiotic Methods for the Synthesis of Radiolabelled Isotopomers - A Review [1] M. Mahnke, T. Moenius Screening of Storage-Stability of 14C Radiochemicals A. Fredenhagen Application of AMS for Human ADME F. Waldmeier, R.C. Garner Binding Studies for Affinity Screening to the Exsorptive Transporter P-Glycoprotein: [3H]Talinolol as Radioligand P. Langguth, A. Koggel, C. Dressler, G. Peinhardt, H. Spahn-Langguth Stable Isotopes in Medicine G.E. von Unruh GMP-Trends for Clinical Trial Samples R. Schnettler, C.R. Oechslein Changes in Radiation Protection in Law in Germany H.-J. Reinecke Information Systems for Radiation Protection J. Gay, H. Graffunder

The structural features and rheological, mechanical, and relaxation properties of poly(ethylene terephthalate) (PET) blends with 7–50 wt % polyester thermoplastic polyester elastomer (TPEE), a block copolymer of poly(butylene terephthalate) and poly(tetramethylene oxide), chemically modified by a diisocyanate chain extender (CE) and reinforced with 30% glass fibers (GF) were studied. The composites were obtained by reactive extrusion with a twin-screw reactor–mixer with a unidirectional rotation of screws. The molecular–structural changes in the materials were judged against data provided by differential scanning calorimetry, scanning electron microscopy, relaxation spectrometry, and rheological analysis of the melts. Regardless of the TPEE concentration in the blends with GF-reinforced PET, the addition of CE resulted in the growth of the indices of the mechanical properties at straining, bending, and impact loading and an increase in the melt viscosity. In addition, an increase in the average length of short GFs in the composites and an intensification of interphase adhesion in the polyester binder–GF surface system were observed. The introduction of CE promoted a slowdown in PET crystallization in the composites and intensified the interphase adhesion in the binder–GF system at temperatures higher and lower than the PET glass-transition temperature. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45711.

Novel polyurethane (PU) ionomers based on poly(teramethylene oxide) (PTMO) or poly(ethylene oxide) (PEO), with nonionic hard segments of varying length and flexible segments containing sodium ions (Na + ), have been prepared and their structure-property relationships have been investigated. The structure and the morphology were studied by means of differential scanning calorimetry (DSC), infrared (IR) spectroscopy and small-angle X-ray scattering (SAXS). Ionic conductivity was studied by means of broadband dielectric relaxation spectroscopy (DRS, 10 -2 -10 9 Hz). PTMO-based ionomers are characterized by the coexistence of segment microphase separation and ionic group segregation morphologies. In the PEO-based ionomers, crystallization is observed at low hard segment content, with a tendency for crystallization to decrease upon hard segment extension. Values of ionic conductivity are in the range 10 -7 Sm -1 to 10 -4 Sm -1 at 323 K for PU ionomers based on PTMO and PEO, respectively.

Tritiated leukotriene A4 and 8-epi-prostaglandin F 2α methyl esters were prepared from the corresponding acetylenic precursors by selective reduction with tritium gas to provide a probe for the metabolite identification of these oxylipins. Partially deactivated Pd-catalysts were prepared from commercial products and their composition was optimized to achieve the better selectivity. A micro-method for the saponification of labelled oxylipins methyl esters was used.

The procedure of selective hydrogenation with gaseous tritium of 16α,17α-cyclohex-3'-en-pregna-1,4-dien-3,20-dione (StO) has been elaborated, and isotopically labelled 16a,17a-cyclohexanopregna-1,4-dien-3,20-dione (St1), 16α, 1 7α-cyclohex-3'-en-pregn-4-en-3,20-dione (St2), 16α,17α-cyclohexanopregn-4-en-3,20-dione (St3) with molar radioactivity of 41, 44, 85 Cilmmol, respectively, obtained. By hydrogenation with gaseous hydrogen, tritium labelled (St3) was converted to 16α, 17α-cyclonexano-5α-pregnan-3,20-dion (5α-St4) and 16α,17α-cyclohexano-5β-pregnan-3,20-dione (5β-St4).

Bis(dialkylamino)carbenium salts {[(Me2N)2CCl]+}2MCl4 2− (M=Ni, Pd) and {[Me2NC(X)NR2]+}2PtCl6 2− (R=Me, All; X=H, Cl, Me) are efficient catalysts for hydrosilylation of allyl phenyl ether, triallylamine, allyl chloride, allylamine, and 1-octene with various hydrosilanes. The catalytic activity is dependent on the salt composition and the nature of the metal M, the saturated compound, and the hydrosilane used. The catalysts used are usually insoluble in the reaction mixture, active, and stable. In some cases, carbenium salts are more selective than Speier's catalyst. Novel catalysts, silica-immobilized dialkylaminocarbenium salts, have been prepared. The kinetics of the reaction have been considered.

Experiments were performed under controlled conditions on the development of four cucumber pests (Trialeurodes uaporariorum, Tetranychus urticae, Aphis gossypii and Thrips tabaci). The main variables were temperature, photoperiod and light intensity. The effect of these factors on the natural enemies Encarsia formosa and Amblyseius mckenziei was also assessed. Comparison of the results allows recommendations on manipulation of the glasshouse environment to favour biological control.

Various mechanisms of hydrogen spillover are discussed. A number of evidences are given that tritium incorporation by isotope exchange occurs with the participation of both tritium cations and atomic tritium. The molar radioactivity of the labeled products prepared at temperatures of up to 180°C is, apparently, mainly determined by reactions of the organic compound with tritium cations, and the degree of isotope exchange depends chiefly on the efficiency of tritium spillover to the bulk of the organic substance supported on the catalyst.

We have obtained multiple-tritium-labelled 5-α-androstan-3-one, dihydropicrotoxin, dimethyl-propyl-3-chloro-butyl-ammonium chloride, 2,2-di(trifluoromethyl)-3,3-dicyanobicyclohept[2,2,1]ane, dihydroalprenolol, undecanoic acid, dihydro-m,m'-di-tert.-butyl-p-coumaric acid and dihydrofusicoccin. By varying the conditions for the hydrogenation of terminal double bonds one can considerably increase the molar radioactivity of such compounds through isotopic exchange. We discuss some tentative explanations of the effect of the labelling reaction conditions upon the synthesis of compounds with desired properties.

2, 6-Dimethyl-3-methoxycarbonyl-5–([2, 3-3H2] -n-propoxy-carbonyl)-4-(2′ -difluoromethoxyphenyl)-1, 4-dihydropyridine and 2, 6-dimethyl-3, 5-di([2, 3-3H2] -n-propoxycarbonyl)-4-(2′-difluoromethoxyphenyl)-1, 4-dihydropyridine were prepared by catalytic tritiation of the respective 3-allyloxy-carbonyl and 3,5-di (allyloxycarbonyl) derivatives of riodipine. The two novel radioactively labeled 1,4-dihydropy-ridine derivatives obtained were shown to be suitable molecular tools for the identification of membrane-bound and solubilized dihydropyridine receptors associated with calcium channels in rabbit skeletal muscle.

An analysis of the degree of positron localization on alloy components is developed in application to palladium, tantalum, and yttrium hydrides. The method is based on the account of positron-ionic core electron interaction. From the results a conclusion is made about a principal positron localization on metallic components. The degree of the localization depends on the nature of the transition metals. The electronic structure of a hydrogen ion can be changed from the partial “proton” state (PdH) up to nearly the complete “proton” state (YH). The anionic hydrogen state is excluded. Die Analysierungsmethode fur den Positronenlokalisierungsgrad an den Legierungskomponente wird fur die Anwendung auf Palladium-, Tantal- und Yttriumhydride weiterentwickelt. Die Methode beruht auf der Positronen-Ionenrumpf-Elektronenwechselwirkung. Aus den Ergebnissen dieser Arbeit werden Schlusse uber die prinzipielle Positronenlokalisierung an den metallischen Komponenten gezogen. Der Grad der Lokalisierung hangt von der Natur des Ubergangsmetalls ab. Die elektronische Struktur eines Wasserstoffions kann von dem partiellen „Protonen”-Zustand (PdH) zu dem nahezu vollstandigen „Protonen”-Zustand (YH) geandert werden. Der anionische Wasserstoffzustand wird ausgeschlossen.

The paper describes the synthesis of [5,6-3H2]PGE1, 15-fluoro-15-deoxy-[5,6-3H2]PGE1 and 11-deoxy-[5,6,10,11-3H4]PGE1 through selective hydrogenation in the presence of heterogeneous and homogeneous catalysts. With heterogeneous catalysts, the yield of labelled compounds was 35%. If bulk substituents were introduced and (Ph3P)3RhCl was used as the catalyst, the yield of labelled prostaglandins was increased to 70%.

Tritium-labelled lipid preparations are obtained by heterogeneous isotopic exchange with gaseous tritium in solution. After appropriate purification, the localization of the label was determined in the main fragments of [3H]-compounds. The obtained data on specific radioactivity and the pattern of label localization allow an insight into processes taking place on labelling under particular experimental conditions.

The complete chemical synthesis of unsaturated precursors of eicosanoids of series 1,2,3 is described. Selective hydrogenation by gaseous tritium of eicosapolyenoic acid acetylenic analogues was used to introduce the label into dihomo-α-linolenic, arachidonic and timnodonic acids, from which [3H]PGE, [3H]PGD and [3H]TXB2 were obtained by biosynthesis. From [3H]PGE multiply labelled PGA, PGB, PGFα, PGI2ME, 6-keto-PGF1αME were synthesized by chemical methods.

1. A method was developed for the preparation of difluoronitromethyl-containing ethers by the alkylation of difluoronitroethanol with alkyl halides in alkaline medium, 2. The chemical properties of the difluoronitromethyl-containing unsaturated ethers were studied.