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calculated from the oxidation potential versus the internal standard of ferrocene/ferrocenium and the I p (5.43 eV) so obtained for PATPD was in good agreement with the I p reported for TPD based materials (5.4 eV determined by UV-PES) [26].Absorption Spectra: Absorption spectra of the samples were measured with a Cary 5G spectrophotometer.Dark Conductivity and Photoconductivity: Steady-state conductivity properties were determined in the dark. To measure the steadystate dark conductivity, an electric field (E a ) was applied and the current (i dark ) was measured. To assure steady-state conditions a dwell time of 15 s between each reading was used. The applied electric field was swept from 0 to 76 V lm ±1 over a period of 7 min. The current was measured using a Keithley 6517A electrometer.Four-Wave Mixing and Exposure Dependent Transient Four-Wave Mixing Experiments: A detailed discussion about the experimental set-up is given in [22].

“Side-chain-type” and crosslinkable quaternized polypropylene was prepared by heterogeneous Ziegler–Natta catalyst mediated polymerization for use in highly stable anion exchange membranes.

Recently, the viscosity of a predominantly amorphous silicon carbonitride (Si 1.7 C 1.0±0.1 N 1.5 ) alloy with an apparent glass-transition temperature (T g ) of 1400°-1500°C was studied. In this study, the creep behavior of silicoboron carbonitride (Si 2 B 1.0 C 3.4 N 2.3 ), which seems to have a T g value of >1700°C, was examined. Both materials exhibited a threestage creep behavior. In stage I, the creep rate declined, because of densification. In stage II, the strain rate approaches a steady state. In stage III, it resumes a declining strain rate, which ultimately decreased below the measurement limit of the system. At 1550°C in stage II, the viscosity of silicoboron carbonitride was six orders of magnitude higher than that of fused silica. Among the Si-C-N ceramics, only chemical-vapor-deposited and reaction-bonded silicon carbides seem to have greater creep resistance than the silicoboron carbonitrides at temperatures >1550°C.

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The piezoresistive behavior of a silicon carbonitride ceramic derived from a polymer precursor is investigated under a uniaxial compressive loading condition. The electric conductivity has been measured as a function of the applied stress along both longitudinal and transverse directions. The gauge factor of the materials was then calculated from the data at different stress levels. The results show that the material exhibits an extremely high piezoresistive coefficient along both directions, ranging from 1000 to 4000, which are much higher than any existing ceramic material. The results also reveal that the gauge factor decreases significantly with increasing applied stress. A theoretical model based on the tunneling–percolation mechanism has been developed to explain the stress dependence of the gauge factor. The unique piezoresistive behavior is attributed to the unique self‐assembled nanodomain structure of the material.

The creep viscosity of chemical-precursor-derived silicon carbonitride (SiCN), which is known to remain predominantly amorphous at temperatures below 1400°C, was measured in the temperature range 1090-1280°C. Experiments were done in uniaxial compression at constant loads in pure nitrogen atmosphere. The creep behavior exhibited three stages. In stage I the strain rate decreased rapidly with time and deformation was accompanied by densification. In stage II the samples exhibited a steady-state creep rate. In stage III, which commenced after long-term deformation, creep gradually declined to rates that were below the sensitivity of our apparatus. The relative density of the specimens during stage II and stage III remained constant at ≈2.3 g/cm 3 . The shear viscosity in stage II was nearly Newtonian and was measured to be 1.3 × 10 13 -5.0 × 10 13 Paؒs at 1280°C, which is approximately 10 3 times the value for fused silica. The creep-hardened as well as uncrept specimens contained silicon nitride crystallites. The volume fraction of these crystals was variable but always less than 5%. Such a small volume fraction of crystals does not explain the dramatic creep-hardening behavior in stage III, even if it is assumed that the crystals formed during creep deformation in stage II.

L-Ti3C2 was prepared by exfoliating Ti3AlC2 in 40% HF. With sulfur-loaded L-Ti3C2 as cathodes, Li–S batteries deliver a high initial discharge capacity of 1291 mA h g−1, an excellent capacity retention of 970 mA h g−1 and coulombic efficiency of 99% after 100 cycles.