Electrolytic reduction of molybdophosphate in aqueous acetonitrile and its application to flow-coulometric determination of orthophosphate

The formation and electrolytic reduction of molybdophosphate in aqueous solutions of various water-miscible organic solvents have been extensively investigated. Acetonitrile was found to be the most useful of these solvents. Two species of molybdophosphate are formed in aqueous acetonitrile, one of which changes spontaneously into the other, which is quite stable and undergoes a 2-electron electrolytic reduction. On the basis of these facts, a flow-coulometric method for orthophosphate has been developed, applicable to the range 5 × 10⁻⁶-1 × 10⁻³M. It has been used for determination of orthophosphate in several phosphorus compounds, some of which are acid-labile.     

Total synthesis of a macrocyclic spermidine alkaloid,codonocarpine

Total synthesis of codonocarpine ($\text{5}$) and its regio-isomer ($\text{1}$$\text{5}$) utilizing a new cyclization procedure is described.     

Opposite-side angular correlation of high-pT particles as a probe of gluons

Opposite-side angular distributions of high-p_T particles in the jet trigger experiments are studied in the lowest-order QCD. Gluon jets play a crucial role in understanding correlations between two high-p_T jets. The angular distribution of the positive-to-negative particle ratio and that of charmed particles can be good probes of the gluon density inside a nucleon.     

Effects of degree of crystallinity upon dielectric behaviors in some aromatic Polyesters

Zusammenfassung An vier polymerhomologen Reihen von Oligomeren des Nylon 6-, Nylon 66- und Polyurethantyps wurde der Einfluß einer Temperaturvorbehandlung, der Phenolquellung und der Kristallisationsbedingungen auf die Langperiode röntgenographisch untersucht. Es wurde der Polymerisationsgrad festgestellt, bei dem die Oligomeren der vier Reihen erstmalig moleküllängenunabhängige Langperioden nach Art der vonHeß undKießig in Röntgenogrammen von Polyamiden und Polyestern entdeckten Kleinwinkelinterferenzen liefern.Das Auftreten vonHeß-Kießig-Reflexen in denKratky-Diagrammen der höheren Oligomeren wird durch Kettenüberfaltung erklärt.XXVII. Mitt. über Oligomere. XXVI. Mitt. vgl.Zahn, H., J. Kunde undG. Heidemann, Makromol. Chem.43, 220 (1961).Dem Andenken anKurt Heß gewidmet.Wir danken dem Bundeswirtschaftsministerium (Forschungsvorhaben J 272), dem Fonds der Chemischen Industrie, Düsseldorf, sowie der Deutschen Forschungsgemeinschaft, Bad Godesberg, für die Förderung dieser Arbeit.     

Extraction—spectrophotometric determination of cadmium with diphenylcarbazone in the presence of 1,10-phenanthroline

The addition of 1,10-phenanthroline improves both the extraction and the spectrophotometric sensitivity of the determination of cadmium with diphenylcarbazone. Slope analysis suggests the formation of a 1:2:2 extracted species. The molar absorptivity is 9.4 × 10⁴ l cm^-1 mol^-1 at 536 nm and extraction is maximal at pH 8.2–9.8. Extraction is rapid and absorbances remain constant at room temperature for 48 h. Various divalent metal ions interfere.     

Solid-liquid interfacial energy In Fe40at%Ni14at%P6at%B alloy glass

Based on nucleation theory, the solid-liquid interfacial energy is estimated to be about 87 ± 2 mJ/m² by the use of the nucleation frequency, supercooled liquid viscosity, and the melting point of Fe40at%Ni14at%P6at%B alloy glass. The value of this energy is found to be quite close to that estimated by means of Turnbull's assumption applied in covalent elements.     

Adsorption of microstructured particles at liquid-liquid interfaces

The solid particles are adsorbed at interfaces and form self-assembled structures when the particles have suitable wettability to both liquids. Here, we show theoretically how the microstructure on the particle surface affects their adsorption properties. The physical properties of the interface adsorbing a particle will be described by taking into account the surface roughness due to the microstructure. The microstructure on the surface changes drastically the wettability and the equilibrium position of the adsorbed particle. Therefore, the contact angle of the particle at the three-phase contact line shifts with the particle surface area, because the surface roughness enhances the interfacial properties of the particle surface. Moreover, the range of the interfacial tensions at which the particle is adsorbed becomes narrower with the increase of the surface roughness. The effect of the particle shape on the adsorption properties is also studied. In the case of disk-shaped particles, the energy changes discontinuously when the plane surface of the particle contacts the liquid-liquid interface. The adsorbing position does not change with the surface roughness. The orientation of a parallelepiped particle at the liquid-liquid interface is governed by the aspect ratio and the surface area of the particle. On the other hand, the particle which is partially covered with the microstructured surface is adsorbed firmly at the interface in an oriented state. We should consider not only the interfacial tensions but also the surface structure and the particle shape to control the adsorption behavior of the particle.     

Bidirectional and colorimetric recognition of sodium and potassium ions

Host 1 based on the phenolphthalein skeleton and two crown ether moieties demonstrated opposite behaviors toward sodium and potassium cations caused by bidirectional complexation. [reaction: see text]     

Ascent of open-circuit voltage on diamond-like carbon photovoltaic cell by infrared heating-assisted pulsed-laser deposition

Phosphorus-doped diamond-like carbon (DLC) films were deposited on quartz and p-type silicon (p-Si) substrates by pulsed-laser deposition. Open-circuit voltage (V _oc) and short-circuit density (I _sc/cm²) from a heating process converted from one type of electrode to another and the two types of electrode pattern are shown by the V–I characteristics. The first heating process was by a ceramic heater, and the other was by an infrared heater. We adopted two electrode patterns, from a bipectinate electrode and a plot pattern electrode, to measure electric photovoltaic characteristics. We were able to upgrade V _oc and I _sc/cm² to 35∼45 mV, and 0.24 μA/cm², respectively, under infrared heating. V _oc by the plot pattern electrode was over 2 V under infrared heating and ceramic heating did not match this on deposition by the PLD method.