Characterization of Zn−Fe intermetallic compounds

Zn?Fe intermediate phases have been investigated. The distribution of quadrupole splittings P(QS) was determined from the Mössbauer spectrum: the P(QS) gives evidence for two different iron sites in the γ phase. The analysis of Mössbauer spectrum taken in an applied magnetic field shows the negative sign of electrical field gradients is present.     

Transport of monosaccharides through a liquid membrane mediated by lipophilic alkaline earth metal complexes

Lipophilic alkaline earth metal complexes, prepared from the corresponding metal hydroxides and phosphoric acid diesters, are quite effective for the transport of some monosaccharides, especially ribose, across a chloroform liquid membrane under neutral conditions.     

Analysis of dynamical optogalvanic effect of Ne in the μs region observed by chopped CW laser. Evidence for collisional mixing and the role of the atoms near the cathode surface

The transient optogalvanic spectrum of Ne 585.2, 588.2, and 603.0 nm lines was observed using a chopped CW dye laser in the negative glow region of a hollow cathode lamp. The analysis revealed that the signal originates mainly from the vicinity of the cathode surface and that the hitherto utilized model of the effect has to be generalized to include the colisional mixing among nearby levels into the rate equations for the population distribution among atomic levels.     

Charpy impact and dart drop impact

In the selection of an appropriate material which satisifes the impact strength requirement for an injection moduled product, the Charpy, Izod or dart drop test methods should be used according to the impact mode displayed by the product—that is, either snap impact on a bar or impact on a shell structure—because generally the ranking of a material determined by the Charpy test differs from that determined by the dart drop test. However, preference for the Charpy test, because of the advantage of simples evaluation work, sometimes leads to erroneous judgement of product characteristics. The breaking behaviour of various materials as determined by Charpy apparatus equipped with instrumentation was studied, and a new design of Charpy test was shown to correlate with the dart drop impact test. The procedure used was to provide a bigger notch tip radius, to break the specimen parallel to the flow direction in the injection moulding process, and to apply the energy absorbed until the beginning of fracture at the notch end.     

Tunable phase conjugation by intracavity degenerate four-wave mixing in an injection-seeded solid dye laser

We demonstrate efficient degenerate four-wave mixing in a laser injection-seeded solid dye laser. Phase-conjugate energy of as much as 140 times the total energy injected externally into the phase conjugator was extracted. Moreover, efficient phase-conjugate energy was obtained in the broad wavelength region from 558 to 567 nm.     

Ab initio inter-radical potential for p-phenylenediamine radical cation dimer

Ab initio molecular orbital calculations were carried out to investigate the inter-radical interaction of the paired p-phenylenediamine radical cations in the singlet state. After initial optimization of the dimer in the parallel sandwich (D2h) and parallel displaced (Cs) configurations at the B3LYP/6-31G* theoretical level, the MP2/6-31G* and B3LYP/6-31G* single energies of the dimer were calculated as a function of the inter-radical distance R. The depths of the potential minima near R = 3.2 A were estimated to be in the order of the hydrogen bonding energy, assuming that the electrostatic contribution between the cations is canceled out by the attractive contributions due to the counter anions on the aspect of a simple electrostatic model. This can be related to the indications of the cation dimer formation in solution in the presence of counter anions at a low temperature reported previously in the literature by resonance Raman and electronic absorption spectra. The inter-radical (Raman active) frequencies of the dimer were calculated, one of which corresponds to the reported value at 161 cm(-1) observed in the resonance Raman spectrum in ethanol at 200 K by Yokoyama and Maeda (Chem. Phys. Lett. 48 (1977) 59).     

SiH4 adsorption on SiGe(0 0 1)

The adsorption process of silane (SiH₄) on a SiGe(0 0 1) surface has been investigated by using infrared absorption spectroscopy in a multiple internal reflection geometry. We have observed that SiH₄ dissociatively adsorbs on a SiGe(0 0 1) surface at room temperature to generate Si and Ge hydrides. The dissociation of Si- and Ge-hydride species is found to strongly depend on the Ge concentration of the SiGe crystal. At a low Ge concentration of 9%, Si monohydride (SiH) and dihydride (SiH₂) are preferentially produced as compared to the higher Si hydride, SiH₃. At higher Ge concentrations of 19%, 36%, on the other hand, monohydrides of SiH and GeH and trihyderide SiH₃ are favorably generated at the initial stage of the adsorption. We interpret that when SiH₄ adsorbs on the SiGe surface, hydrogen atoms released from the SiH₄ molecule stick onto Ge or Si sites to produce Si or Ge monohydrides and the remaining fragments of -SiH₃ adsorb both on Si and Ge sites. The SiH₃ species is readily decomposed to lower hydrides of SiH and SiH₂ by releasing H atoms at low Ge concentrations of 0% and 9%, while the decomposition is suppressed by Ge in cases of 19% and 36%.     

Degree of roots of disk twists on 3-dimensional handlebodies

Margalit and Schleimer (Geom Topol 13(3):1495–1497, 2009) discovered a nontrivial root of the Dehn twist about a nonseparating curve on a closed oriented connected surface. McCullough and Rajeevsarathy (Geom Dedicata 151(1):397–409, 2011) and Monden (Rocky Mt J Math, to appear) obtained the evaluation of the degrees of roots of Dehn twists. In this paper, we discuss existence and degrees of homeomorphisms whose power is equal to disk twist about a nonseparating disk in the mapping class group of the 3-dimensional handlebody.