Mutual interference coefficients obtained for 639 emission lines of 68 elements in routine analysis by ICP-AES

In our previous report [1], a practical method to obtain spectral interference coefficients and to select analytical lines in ICP-AES has been suggested.The coefficients were defined as apparent mass of the analyte corresponding to the spectral interference observed for unit mass of the interferent. In this report, data of the experimentally obtained mutual interference coefficients among 639 emission lines of 68 elements are presented. The data would be also useful for different resolution spectrometers in routine analysis, they are presented on 69 Tables as Supplementary Electronic Material.     

Formation and morphology of “shish-like” fibril crystals of aliphatic polyesters from the sheared melt

We found the formation of “shish-like” fibril crystals of aliphatic polyesters such as poly(l-lactic acid) (PLLA), poly(ε-caprolactone) (PCL), poly(12-hydroxydodecanoic acid) (PHDA) and poly(16-hydroxyhexadecanoic acid) (PHHA) from the sheared melt with shear rate  = 5 s⁻¹ observed by polarizing optical microscope (POM). The melting temperature T_ms of obtained fibril crystals of PLLA and PCL were higher than those of spherulites and were close to the equilibrium melting temperature . The small angle X-ray scattering (SAXS) patterns from the bulk sample including fibril crystals, small amount of unoriented small crystals and amorphous showed no peaks arose from the existence of long periods in fibril crystals. These are the evidence that the observed fibril crystals consist of assemblies of a lot of extended chain crystals (ECCs). We observed the morphology of moderately extracted single strand of fibril crystals at the magnification of POM by means of scanning electron microscope. We found that macroscopic fibril crystals of PLLA with diameter d = 10 μm consist of the bundle structure of microscopic fibril crystals with d = 2 μm. From POM observation of the formation of fibril crystals of PLLA and PCL, we showed phase diagrams of molecular weight M and crystallization temperature T_c for the formation of fibril crystals. From these phase diagrams, we evaluated a critical M and T_c for the formation of fibril crystals. Moreover, from the sequential melting and crystallization experiments, it was implied that the entanglement and transesterification play an important role on the formation of fibril crystals of aliphatic polyesters.     

Flow-injection determination of L-histidine with an immobilized histidine oxidase from Brevibacillus borstelensis KAIT-B-022 and chemiluminescence detection.

A chemiluminometric flow injection analytical system for the quantitation of L-histidine is described. Histidine oxidase (EC 1.4.3.-) from Brevibacillus borstelensis KAIT-B-022 was immobilized on tresylated poly(vinyl alcohol) beads and packed into a stainless-steel column. The hydrogen peroxide produced was detected chemiluminometrically by a flowthrough sensor containing immobilized peroxidase (EC 1.1 1.1.7). The maximum sample throughput was 10 h(-1). The calibration graph was linear from 0.05 to 5 mM; the detection limit (signal to noise ratio = 3) was 0.01 mM. The activity of immobilized histidine oxidase reduced to 65% of the initial value after 350 injections. The system was applied to the determination of L-histidine in fish meat, such as salmon, tunny, bonito, and mackerel.     

Estimation of local density augmentation and hydrogen bonding between pyridazine and water under sub- and supercritical conditions using UV-vis spectroscopy.

The local density around pyridazine was evaluated by examining the UV-vis spectral shift of pyridazine in a high-pressure liquid state and supercritical water from 25 to 450 degrees C and from 20 to 45 MPa. Augmentation of the local density was observed from 380 to 420 degrees C, and showed the maximum at a lower density than the critical density of water. The degree of hydrogen bonding was estimated in consideration of the local density augmentation. The estimated degree of hydrogen bonding under subcritical conditions without any difference between the local density and the bulk density corresponded to the previously reported results with a UV-vis absorbance spectral shift of quinoline and an NMR proton chemical shift. However, the degree of hydrogen bonding near the critical point of water was larger than that in the case that the local density augmentation was not taken into account. At 380 degrees C and 0.2 g cm(-3) of the bulk density there are 30% as many hydrogen bonds as those under the ambient condition, and it was around 1.5-times that without considering local-density augmentation.     

Novel copper hydride-promoted 1,3-rearrangement of α-allenylcyclopropane systems to methylenecyclopentenes

α-Allenylcyclopropanedicarboxylates, for which a novel synthetic method has been devised by conjugate addition of a copper hydride (Stryker) reagent to α-cyclopropylpropargylic esters, have been newly found to be smoothly converted to methylenecyclopentene derivatives under mild reaction conditions by further treatment with the copper hydride reagent. The mechanistic pathway is discussed.     

A traceless solid phase synthesis of thiomorpholin-3-ones

A novel synthesis of thiomorpholin-3-ones using a traceless solid phase approach is described, in which many kinds of thiomorpholin-3-ones were efficiently obtained in high purity based on an intramolecular alkylation of sulfides followed by an elimination of desired thiomorpholin-3-ones from the generated sulfonium salts.     

Hanasanagin: a new antioxidative pseudo-di-peptide, 3,4-diguanidinobutanoyl-DOPA, from the mushroom, Isaria japonica

The ‘Hanasanagitake’ mushroom, Isaria japonica, is a folk medicine and a traditional health food. Fractionation of the 60% ethanol extract of the mushroom, guided by the antioxidant activity test, led to the isolation of a new pseudo-di-peptide, and it was called ‘hanasanagin’. Spectral analysis and chemical transformation determined the structure of hanasanagin as 3,4-diguanidinobutanoyl-DOPA.     

Preparation of nanosized gold particles in a biopolymer using UV photoactivation

Gold nanoparticles have been prepared by UV photoactivation in the presence of a biopolymer, sodium alginate. The particles are characterized by UV-vis spectra and TEM studies. Both particle size and the UV-visible absorption peak are dependent on the sodium alginate concentration. The effects of various other parameters such as change of light source, cell material of the reaction chamber, heating effect, irradiation time, and HAuCl4 concentration are studied. The particles are spherical and in situ stabilized by the biopolymer. The method is very simple and reproducible.     

The tricyclopropylcyclopropenium ion

A novel non-benzenoid aromatic cation, tricyclopropylcyclopropenium ion, was synthesized by smooth addition of photochemically generated cyclopropylchlorocarbene to dicyclopropylacetylene, and was shown to have remarkable stability.