Canonical distribution from kinetic theory

Solution to the Liouville equation for N interacting particles of differing mass is sought in terms of a product of functions of particle momenta and particle coordinates, respectively. Further assuming a product separability of the momentum part of the solution is shown to yield the canonical distribution. The inverse-temperature β parameter emerges in the analysis as a separation-of-variables constant.     

Review of fundamental processes for matter-radiation interaction

A concise review is presented of fundamental quantum electrodynamic processes which are relevant to X-ray lasers, grasers, and superpowerful lasers. Transition rates and cross sections are derived for atomic and free-electron Thomson scattering, Kramers-Heisenberg, and Raman scattering in the dipole approximation; Rayleigh scattering and C?erenkov effect. The resport includes a table of reaction rates, cross sections, stopping power, and power spectra for all processes considered.     

Observation of a resonancelike structure in the pi +- psi' mass distribution in exclusive B-->Kpi +- psi' decays

A distinct peak is observed in the pi +/- psi' invariant mass distribution near 4.43 GeV in B-->K pi +/- psi' decays. A fit using a Breit-Wigner resonance shape yields a peak mass and width of M=4433+/-4(stat)+/-2(syst) MeV and Gamma=45-13+18(stat)-13+30(syst) MeV. The product branching fraction is determined to be B(B 0-->K -/+Z+/-(4430)) x B(Z+/-(4430)-->pi+/-psi')=(4.1+/-1.0(stat)+/-1.4(syst)) x 10(-5), where Z+/-(4430) is used to denote the observed structure. The statistical significance of the observed peak is 6.5 sigma. These results are obtained from a 605 fb(-1) data sample that contains 657 x 10(6) BB pairs collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider.     

Search for B+-->D*+pi0 decay

We report on a search for the doubly Cabibbo suppressed decay B+-->D*+pi0, based on a data sample of 657x10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We find no significant signal and set an upper limit of B(B+-->D*+pi0)<3.6x10(-6) at the 90% confidence level. This limit can be used to constrain the ratio between suppressed and favored B-->D*pi decay amplitudes, r<0.051, at the 90% confidence level.     

Determination of tin in ores and concentrates

A method is described for the determination of tin in cassiterite and stannite ores. The method is based on an ammonium iodide fusion of the ore under controlled heating conditions and the subsequent determination of tin by classical iodimetric technique.     

Exceptionally fast radiative decay of a dinuclear platinum complex through thermally activated delayed fluorescence

A novel dinuclear platinum(ii) complex featuring a ditopic, bis-tetradentate ligand has been prepared. The ligand offers each metal ion a planar O^N^C^N coordination environment, with the two metal ions bound to the nitrogen atoms of a bridging pyrimidine unit. The complex is brightly luminescent in the red region of the spectrum with a photoluminescence quantum yield of 83% in deoxygenated methylcyclohexane solution at ambient temperature, and shows a remarkably short excited state lifetime of 2.1 μs. These properties are the result of an unusually high radiative rate constant of around 4 × 10⁵ s⁻¹, a value which is comparable to that of the very best performing Ir(iii) complexes. This unusual behaviour is the result of efficient thermally activated reverse intersystem crossing, promoted by a small singlet–triplet energy difference of only 69 ± 3 meV. The complex was incorporated into solution-processed OLEDs achieving EQE_max = 7.4%. We believe this to be the first fully evidenced report of a Pt(ii) complex showing thermally activated delayed fluorescence (TADF) at room temperature, and indeed of a Pt(ii)-based delayed fluorescence emitter to be incorporated into an OLED.

Efficient thermally activated delayed fluorescence (TADF) in a brightly luminescent diplatinum(ii) complex results in significant enhancement of the radiative decay rate.     

Hydrogen bonds in ionic liquids revisited: (35/37)Cl NMR studies of deuterium isotope effects in 1-n-butyl-3-methylimidazolium chloride

Detailed knowledge of the structure, dynamics, and interionic interactions of ionic liquids (ILs) is critical to understand their physicochemical properties. In this letter, we show that deuterium isotope effects on the chloride ion 35/37Cl NMR signal represent a useful tool in the study of interionic hydrogen bonds in imidazolium chloride ILs. Sizable Delta35/37Cl(H,D) values obtained for the model system 1-n-butyl-3-methylimidazolium chloride ([C4mim]Cl) upon deuteriation of the imidazolium C-2 and C-2,4,5 positions, of nearly 1 and 2 ppm, respectively, show that the approach can readily identify and differentiate Cl...H hydrogen bonds between the anion and cation. Our study is one of a few examples in which hydrogen-bonding in ILs has been investigated using deuterium isotope effects and, to our knowledge, the only one employing 35/37Cl NMR to detect these interactions. The methodology described could be easily extended to the study of other systems bearing NMR-active nuclei.     

Investigation of "on water" conditions using a biphasic fluidic platform

Converting the DEAD: A fluidic approach to generate precisely defined water-oil interfaces was used to quantify the influence of the water surface (blue drops) on chemical reactions between quadricyclane or β-pinene and diethyl azodicarboxylate (DEAD). This method allows for easy investigation of the "on water" effect.     

Materials Formed by Combining Inorganic Glasses and Metal-Organic Frameworks

Here, we propose the combination of glassy or crystalline metal-organic frameworks (MOFs) with inorganic glasses to create novel hybrid composites and blends.The motivation behind this new composite approach is to improve the processability issues and mechanical performance of MOFs, whilst maintaining their ubiquitous properties. Herein, the precepts of successful composite formation and pairing of MOF and glass MOFs with inorganic glasses are presented. Focus is also given to the synthetic routes to such materials and the challenges anticipated in both their production and characterisation. Depending on their chemical nature, materials are classified as crystalline MOF-glass composites and blends. Additionally, the potential properties and applications of these two classes of materials are considered, the key aim being the retention of beneficial properties of both components, whilst circumventing their respective drawbacks.