Origins for epitaxial order of sexiphenyl crystals on muscovite(001)

The epitaxial order of sexiphenyl crystals on muscovite(001) is investigated by x‐ray diffraction, lattice misfit calculations and atomic force microscopy. Depending on the substrate temperature during the thin film growth process, different epitaxial orientations are formed. Sexiphenyl thin films prepared at 370 K preferentially form crystals with the crystallographic (11‐1) planes parallel to the substrate surface while at 434 K a strong fraction of crystals with (11‐2) orientations is grown. The epitaxial orders of sexiphenyl crystals are compared with lattice misfit calculations. The in‐plane order of the {11‐1} crystals can be explained by a point‐on‐line coincidence I, which reveals that the interface is formed by undisturbed crystal surfaces. The epitaxial order of the {11‐2} oriented crystals is characterised by the experimental observation that low indexed crystal directions in the sexiphenyl(11‐2) plane and the muscovite(001) surface coincide with each other, forming a near‐coincidence case. Corrugations of the substrate surface are responsible for this second type of epitaxial order. Characteristic features in the thin film morphology could be correlated to the two observed epitaxial orientations of the sexiphenyl crystals. Copyright © 2009 John Wiley & Sons, Ltd.     

Growth of Escherichia coli under extremely low-frequency electromagnetic fields

The inflence of extremely low-frequency (ELF) electromagnetic fields on Escherichia coli cultures in submerse fermentation was studied. The fermentation processes were carried out recycling the culture medium externally through a stainless steel tube inserted in a magnetic field generator (solenoid). The exposure time and electromagnetic induction were varied in a range of 1 to 12 h and 0.010 to 0.10 T, respectively, according to a Box-Wilson Central Composite Designs of face centered with five central points. Growth of E. coli could be altered (stimulated or inhibited) under magnetic fieldinduced effects. E. coli culturesexposed at 0.1 T during 6.5 h exhibited changes in its viability compared to unexposed cells, which was 100 times higher than the control. The magnetic field generator associated with the cellular suspension recycle is a new way of magnetic treatment in fermentation processes and could be appropriate to industrial scale up.     

Study of quasi two-body final states in K−n reactions at 8.25 GeV/c

Cross sections for various channels in 3 prong + V₀ final states of K^?n interactions are obtained at 8.25 GeV/c. An energy dependence study of the quasi two-body reactions Σ^?(1385) + vector meson and ΛB^? seem to imply the presence of cuts in the Regge exchange formalism, whereas the reaction Δ(1236) $\text{K}$¹ (890) does not require such cuts. Upper limits of 1 and 2 μb are found for the reactions K^?n → ΛA₁ and K^?n → ΛA₂.     

Hierarchy of mean multiplicities in pn and π+n interactions at 195 GeV/c

The dependence of the average charged multiplicity, 〈n_X〉, of the system X on |t| and M²_X is studied for the reactions p(π⁺)n→p_fast(p⁺_fast) + X and p(π⁺)n→p_slow + X at 195 GeV/c. For a fixed M²_X, 〈n_X〉 changes significantly among these reactions, yielding a systematic hierarchy of mean multiplicities. The results indicate that a proton emits on the average less charged particles than a pion and more than a neutron.     

Electrical conductivity as a method to study kinetics of solid-state reactions

A model for changes of electrical conductivity in the course of solid-state reaction has been demonstrated; it describes well the changes in the electrical conductivity of the reacting mixture ZnSe + Cr₂Se₃. The measurement method, the experimental data and the results calculated from the formulas derived in a previous publication have been presented. The experimental and theoretical curves of the temperature dependence of the electrical conductivity have similar shape. The theoretical values differ a little from the experimental ones. These differences allowed us to estimate the character of the changes of the concentration of defects in the product in the course of the reaction. Analysis of the assumptions and the application of the formulas previously presented was made.     

Untersuchungen über die Kinetik und den Mechanismus der Bindung von Schwefeldioxid und Stickoxiden durch gasförmiges Ammoniak

Studies on Kinetics and Mechanism of the Reaction of Sulphur Dioxide and Nitrogen Oxides with Gaseous Ammonia It was found that depending on the partial pressure of SO₂, H₂O, and NH₃ different solid products were formed. Formation of the product containing the smallest amount of the substrate of the lowest partial pressure is favoured. The measured stability limits of the solid products confirmed the former thermodynamic calculations. The conditions for effective binding of NO_x with ammonia were established.     

Structure in the reaction π+p → Δ++ϱo AT 5 GeV/c

In a high statistics experiment a large dσ/dt′ slope of (23.7 ± 3.2) GeV^?2 is obtained in the forward direction. The natural parity exchange cross-section shows a dip at t′ ≈ 0.2 GeV² and peak at ≈ 0.6 GeV². The ?^o is separated from the S-wave background and we obtain ?₀₀^F ≈ 0.94, at t′ = 0.