Reheating decomposition process as chemical recycling for rigid polyurethane foam

We have found that a reheating process for the products in the chemical recycling of rigid polyurethane foam by an extruder with diethanolamine as a decomposing agent is effective for improving the product stability. The product with stable viscosity was obtained by the reheating process at 175-200 °C for 2 h, regardless of the extruding condition. An amine adduct, which is an intermediate, was found to be the cause of instability of the discharged product from the extruder. At the initial stage of reheating, the intermediate decomposed, releasing toluenediamine, which promoted further decomposition of the discharged products. We have succeeded in controlling the quality of the recycled products.     

HREELS, STM, and STS study of CH(3)-terminated Si(111)-(1x1) surface

An ideally (1x1)-CH(3)(methyl)-terminated Si(111) surface was composed by Grignard reaction of photochlorinated Si(111) and the surface structure was for the first time confirmed by Auger electron spectroscopy, low energy electron diffraction, high-resolution electron energy loss spectroscopy (HREELS), scanning tunneling microscopy (STM), and scanning tunneling spectroscopy (STS). HREELS revealed the vibration modes associated to the CH(3)-group as well as the C-Si bond. STM discerned an adlattice with (1x1) periodicity on Si(111) composed of protrusions with internal features, covering all surface terraces. The surface structure was confirmed to be stable at temperatures below 600 K. STS showed that an occupied-state band exists at gap voltage of -1.57 eV, generated by the surface CH(3) adlattice. This CH(3):Si(111)-(1x1) adlayer with high stability and unique electronic property is prospective for applications such as nanoscale lithography and advanced electrochemistry.     

Synthesis of pyridine N-imine complexes of methylcobaloxime and reactions of bis(dimethylglyoximato)methyl(Pyridine N-imine)cobalt with acid anyhydrides and acetylenedicarboxylic acid dimethyl ester

Pyridine N-imine complexes of methylcobaloxime, CH₃Co(Hdmg)₂(R¹— C₅H_nN⁺N^?H) (n = 4; R¹ = H, 2-CH₃, 3-CH₃, 4-CH₃: n = 3; R¹ = 2,6-CH₃), have been synthesized by the reaction of CH₃Co(Hdmg)₂S(CH₃)₂ with a pyridine N-imine which is generated from a pyridine, hydroxylamine-O-sulfonic acid and K₂CO₃. The reactions of CH₃Co(Hdmg)₂(C₅H₅N⁺N^?H) with acid anhydrides form new methylcobaloxime complexes with N-substituted pyridine N-imines, CH₃Co(Hdmg)₂(C₅H₅N⁺N^?R²) R² = COPh, COMe, COEt). With maleic anhydride, (pyridine N-acryloylimine)carboxylic acid is formed. With acetylenedicarboxylic acid dimethyl ester, 1,3-dipolar cycloaddition of the ligand gives pyrazolo[1,5-a]pyridine-2,3-dicarboxylic acid dimethyl ester.     

Rational methods for predicting human monoclonal antibodies retention in protein A affinity chromatography and cation exchange chromatography. Structure-based chromatography design for monoclonal antibodies

Rational methods for predicting the chromatographic behavior of human monoclonal antibodies (hMabs) in protein A affinity chromatography and cation exchange chromatography from the amino acid sequences information were proposed. We investigated the relation between the structures of 28 hMabs and their chromatographic behavior in protein A affinity chromatography and cation exchange chromatography using linear gradient elution experiments. In protein A affinity chromatography, the elution pH of the hMabs was correlated with not only the structure of the Fc region (subclass), but also that of the variable region. The elution pH of hMabs that have LYLQMNSL sequences in between the CDR2 and CDR3 regions of the heavy chain became lower among the same subclass of hMabs. In cation exchange chromatography, the peak salt concentrations IR of hMabs that have the same sequences of variable regions (or that have a structural difference in their Fc region, which puts them into a subclass) were similar. The IR values of hMabs were well correlated with the equilibrium association constant Ke, and also with the surface positive charge distribution of the variable region of the heavy chain (corrected surface net positive charge (cN) of the VH region). Based on these findings, we developed rational methods for predicting the retention behavior, which were also tested with eight additional hMabs. By considering the information on the number of binding sites associated with protein adsorption as determined experimentally, and the surface positive charge distribution from the three-dimensional structure of Mab A, we hypothesized that hMabs is separated by cation exchange chromatography as the surface positive charge distribution of the VH region is recognized.     

利用高分辨率光谱和从头算理论研究9-甲基蒽的大振幅运动

本文利用平行超音速射流和光频梳技术观察到9-甲基蒽(9MA)的多普勒的高分辨率和高精度光谱. CH₃内部旋转的势能曲线用六重对称正弦函数表示. 之前报道的9MA-d12的势垒(V₆)远远低于9MA-h12[M. Baba, et al., J. Phys. Chem. A 113, 2366 (2009)]. 本文对多组分分子轨道法进行从头算方法的理论计算. 氘代取代势垒降低的部分原因是H和D原子核的波函数不同.     

In situ surface plasmon resonance measurements of self-assembled monolayers of ferrocenylalkylthiols under constant potentials.

A commercial system for surface plasmon resonance (SPR) possessing a batch-type flow channel has been simply modified so as to conduct in situ SPR measurements under polarization of an Au sensor chip at constant potentials. The modified instrument can monitor electrochemical reactions of monolayer materials with high stability and high reproducibility. The redox reaction of a self-assembled monolayer (SAM) of 6-ferrocenyl-1-hexanethiol (FcHT) induced the resonance angle shifts, the magnitudes of which accorded with the Nernst equation. The measurements in electrolyte solutions containing different electrolyte anions revealed that the SPR measurements detected ion pairing of electrolyte anions with oxidized FcHT. In cases of measurements in alkylsulfonic acid solution, simulation of the results based on the N-layer model has clarified that alkylsulfonate anions make an assembled layer on the FcHT SAM.     

Development of a new radiation detector utilizing CNTs as anodes

A new gas-multiplication radiation detector utilizing CNTs as anodes is proposed. A very compact detector with good spatial and temporal resolutions might be built. The designing and development of a prototype detector is described. Argon gas or liquid is adopted as radiation-converting medium. The detector body can be evacuated and cooled down to liquid nitrogen temperature. Silicon wafers on which single-wall CNTs are grown are used as the detector anode.     

Dependence of NO<Subscript>2</Subscript> sensitivity on thickness of oxide-sensing electrodes for mixed-potential-type sensor using stabilized zirconia

The effect of thickness of oxide-sensing electrode (SE) on NO₂ sensitivity of the planar sensor based on yttria-stabilized zirconia (YSZ) was examined at high temperatures. The sensitivity of the sensor increased with decreasing thickness of SE, and the highest sensitivity was obtained by using the thinnest layer of Cr₂O₃–SE (2.7 μm) at 700 °C. In the case of NiO–SE, the highest sensitivity was observed for the sensor using the 4 μm-thick SE even at high temperature of 850 °C. Based on the results of the measurements for the complex impedances, the polarization curves, and the gas-phase NO₂ decomposition catalysis, it was confirmed that the catalytic activity to the gas-phase NO₂ decomposition on the oxide–SE matrix played an important role in determining the NO₂ sensitivity of the present sensors. This artice was accidentally published twice. This is the second publication, please cite only the authoritative first one which is available at . An additional erratum is available at . An erratum to this article can be found at