Spannungsabh?ngigkeit der dielektrischen Eigenschaften von Vulkanisaten aus chloriertem Poly?thylen

Ohne Zusammenfassung     

The photodissociation of alkali halides in air—acetylene flame as studied by molecular absorption spectroscopy

Absorption spectra of alkali salts, which were aspirated into the air—acetylene flame, have been investigated in the u.v. and visible region, where a conventional atomic absorption spectrometer with an analog data processing system was used for obtaining the spectra. Molecular bands which arose from the alkali halides and oxides were observed along with atomic lines. In the case of lithium, only molecular absorption bands of lithium oxide were observed in the flame, even when lithium halides were aspirated. These molecular absorption bands can be interpreted in terms of photodissociation processes of the alkali halides and oxides produced in the flame.     

Reactions of 1,1,3,3-tetramethylindane-2-selone with grignard and organolithium reagents

The title reaction afforded selenophilic, carbophilic, and reduction products depending on the kinds of the organo-metallic reagents and the heterophilic nature of the reaction was more conspicuous in the reaction with the selenoketone than with the corresponding thioketone.     

Measurement of small vibration and deformation by using high order diffraction of a thermoplastic hologram

An experimental study is presented of quasi real-time measurements of small vibration and deformation by using phase difference amplification through high order diffraction of thermoplastic holograms. An optimum recording condition for obtaining high diffraction efficiency of high order diffraction is obtained and the sensitivity becomes three times that of the conventional method.     

Cytotoxicity and anticancer activity of natural rubber latex particles for cancer cells

To broaden the knowledge of cytotoxicity of natural rubber latex (NRL) nanoparticles we for the first time examined the latex biocompatibility in vitro against a panel of cancer cells (A549, A2780, and MDA-MB-231). Owing to fractionation of NRL nanoparticles by ultra-centrifuge, the effect of the non-rubber constituents (intermediate of 5.8 wt% and sediment of 0.2 wt%) on the cytotoxicity was clarified. For intermediate constituent, the half maximal inhibitory concentration (IC₅₀) values at 24 h was 1.05 mg/mL for A549 cells, which was one order of magnitude higher in toxicity as compared to that for A2780 (0.24 mg/mL) and MDA-MB-231 (0.36 mg/mL) cells. In addition, profound studies including cell cycle arrest abilities and apoptosis induction profiles against cancer cells were discussed in detail. It was found that the constituents exhibit some significant effect on the cell cycle arrest and trigger apoptosis for A2780 cells. This effective apoptosis induction profiles was more prominent in MDA-MB-231 cells incubated with NRL nanoparticles and sediment loading conditions. The percentage of apoptotic cells was ca. 6–8% of the total cells.     

Syntheses and Properties of (Nitronyl nitroxide)-substituted Tri-phenylamine ortho-Bridged by Two Oxygen and Sulfur Atoms

A nitronyl nitroxide unit ( NN ) was linked with a triphenylamine-based condensed polycyclic skeleton DOTT to form a radical substituted donor NN - DOTT . X-ray crystal structure analysis demonstrated a flat bowl shape of the DOTT unit. EPR spectra showed the localization of electron spin on the NN unit. Chemical oxidation of the DOTT unit produced radical-substituted radical cation salts NN - DOTT ⁺ ⋅ SbF₆⁻ and NN - DOTT ⁺ ⋅ FeBr₄⁻ that are stable under ambient conditions. The magnetic behavior of NN - DOTT ⁺ ⋅ SbF₆⁻ is characterized by the strong intramolecular ferromagnetic interaction between NN and DOTT ⁺. The X-ray structural analysis of NN - DOTT ⁺ ⋅ FeBr₄⁻ shows planar structure of DOTT and 1D mixed-stack column of NN-DOTT ⁺ and FeBr₄⁻. Magnetic measurements established that NN - DOTT ⁺ ⋅ FeBr₄⁻ undergoes magnetic phase transition into a weak ferromagnet at 7 K.     

From Cs<Subscript>2</Subscript>Mo<Subscript>6</Subscript>Cl<Subscript>14</Subscript> to Cs<Subscript>2</Subscript>Mo<Subscript>6</Subscript>Cl<Subscript>14</Subscript>·H<Subscript>2</Subscript>O and Vice Versa: Crystal Chemistry Investigations

We report here the synthesis, the crystal structure and the luminescent properties of the new cluster compounds Cs₂Mo₆Cl₁₄·H₂O and Cs₂Mo₆Br₁₄·H₂O. Single-crystal X-ray diffraction performed on Cs₂Mo₆Cl₁₄·H₂O indicates that the compound crystallizes in the monoclinic space group C2/c with refined cell parameters a = 19.578 Å, b = 15.151 Å, c = 9.347 Å, and β = 115.64°. The structure can be described from discrete \(\left[ {{\text{Mo}}_{ 6} {\text{Cl}}^{\text{i}}_{ 8} {\text{Cl}}^{\text{a}}_{ 6} } \right]^{ 2- }\) anionic cluster units arranged in a “A–A’–A–A’” pseudo prismatic stacking parallel to (b, c) plane with both Cs⁺ cations and water molecules located between the layers. Moreover, the centric character of the trigonal structure of Cs₂Mo₆Cl₁₄ was also studied by combination of single-crystal X-ray diffraction and both X-ray and neutron powder diffraction. The results suggest an important influence of the sample preparation on the symmetry of the crystal structure. The crystal structure relationship between the \(\left[ {{\text{Mo}}_{ 6} {\text{Cl}}^{\text{i}}_{ 8} {\text{Cl}}^{\text{a}}_{ 6} } \right]^{ 2- }\) anionic cluster unit arrangements in Cs₂Mo₆Cl₁₄ and Cs₂Mo₆Cl₁₄·H₂O is discussed. Finally, the characterization of the luminescent properties of Cs₂Mo₆X₁₄ and Cs₂Mo₆X₁₄·H₂O (X = Cl, Br) indicates that emission profile is comparable regardless existence of water molecule in the crystal structure.     

Newton–Okounkov convex bodies of Schubert varieties and polyhedral realizations of crystal bases

A Newton–Okounkov convex body is a convex body constructed from a projective variety with a valuation on its homogeneous coordinate ring; this is deeply connected with representation theory. For instance, the Littelmann string polytopes and the Feigin–Fourier–Littelmann–Vinberg polytopes are examples of Newton–Okounkov convex bodies. In this paper, we prove that the Newton–Okounkov convex body of a Schubert variety with respect to a specific valuation is identical to the Nakashima–Zelevinsky polyhedral realization of a Demazure crystal. As an application of this result, we show that Kashiwara’s involution (\(*\)-operation) corresponds to a change of valuations on the rational function field.