Three Dimensional Monitoring of Stack Plume Dynamics by a Scanning Mie Lidar System as a Plume Watchdog Station

A scanning lidar system was developed to watch the nighttime diffusion process of plume from a smokestack of a large incinerator located around 3 km from the system. Observed data sets were visualized as three dimensional images in which could be seen the diffusion pattern from any direction, and this made it easy to investigate the exhaust dynamics. Observation results showed that the original plume extended at least 1.6 km, where there was a residential area, from the smokestack increasing in diameter to about 500 m. High density aerosols originating from the smokestack were measured in that area even at midnight. The lidar system performance as a plume watchdog station was discussed from the standpoint of publichealth-related plume monitoring.     

Synthesis,physical properties,and structure of TIPS-difuranoacenes

The synthesis, physical properties, and structure of triisopropylsilylethynyltetracenodifuran (2) and pentacenodifuran (3) derivatives were reported. There showed high stability in solution in the dark, yet decomposed under light. Single crystal of pentacenodifuran was analyzed by X-ray diffraction analysis, and showed one dimensional packing array along the c-axis. The molecules were stacked with a 3.30 Å interlayer distance. The crystals exhibited a high thermal stability under an ambient condition.     

Carbon–Carbon Bond Formation via Catalytically Generated Aminocarbene Complexes: Rhodium‐Catalyzed Hydroaminative Cyclization of Enynes with Secondary Amines

We report a hydroaminative cyclization of enynes using phosphine‐quinolinolato rhodium catalysts. The hydroaminative cyclization of 2‐vinylphenylacetylene derivatives with secondary amines gives 2‐aminoindenes in good yields. The reaction is considered to proceed through carbon–carbon bond formation on a catalytically generated aminocarbene ligand.     

Binary Phase Behavior of 1,3-Distearoyl-2-oleoyl-sn-glycerol (SOS) and Trilaurin (LLL)

This paper reports the precise analysis of the eutectic mixing behavior of 1,3-distearoyl-2-oleoyl-sn-glycerol (SOS) and trilaurin (LLL), as a typical model case of the mixture of cocoa butter (CB) and cocoa butter substitute (CBS). SOS was mixed with LLL at several mass fractions of LLL (w_LLL); the mixtures obtained were analyzed for polymorphic phase behavior using differential scanning calorimetry (DSC) and synchrotron radiation X-ray diffractometry (SR-XRD). In melt crystallization with constant-rate cooling, SOS and LLL formed eutectics in their metastable polymorphs, allowing the occurrence of a compatible solid solution at w_LLL ≥ 0.925. With subsequent heating, the resultant crystals transformed toward more stable polymorphs, then melted in a eutectic manner. For mixtures aged at 25 °C after melt crystallization, eutectics were found in the extended w_LLL region, even at w_LLL = 0.975. These results indicate that phase separation between SOS and LLL progressed in their solid solution under stabilization. The crystal growth of the separated SOS fraction may cause fat-bloom formation in compound chocolate containing CB and CBS. To solve this problem, the development of retardation techniques against phase separation is expected.     

An all-electron calculation of an antihypertensive protein with the Gaussian-based density functional method

An all-electron calculation of the antihypertensive and antiviral protein BDS-I from the sea anemone Anemonia sulcata was carried out using the density functional method based on Gaussian-type orbitals with workstations. Our computer program ProteinDF coded by the object-oriented language C++, was originally designed for all-electron calculations of proteins and controlled in parallel with high efficiency. The numbers of residues, atoms, orbitals and auxiliary functions of the calculated protein were 43, 629, 3615 and 6545, respectively. This Letter reports timing data of the computation and some calculated electronic properties. Our program will open the door for advanced studies of larger proteins.     

Delocalization of positive charge in π-stacked multi-benzene rings in multilayered cyclophanes

In the present study, delocalization of a positive charge in π-stacked multi-benzene rings in multilayered para- and meta-cyclophanes, in which benzene rings are connected by propyl chains to form a chromophore array with the face-to-face structure, was investigated by means of transient absorption spectroscopy during the pulse radiolysis using dichloroethane as a solvent. The local excitation and charge resonance (CR) bands were successfully observed. It was revealed that the CR band shifted to the longer wavelength side with the number of the benzene rings. The stabilization energy estimated from the peak position of the CR band showed the efficient charge delocalization over the cyclophanes. Furthermore, the CR bands showed the slight spectral change attributable to the change in distribution of the conformers. The substantially long lifetime of the CR band can be explained on the basis of the smaller charge distribution on the outer layers of the multilayered cyclophanes.     

Preparation and evaluation of polyamidoamine dendrimer (G2)/branched-��-cyclodextrin conjugate as a novel gene transfer carrier

The purpose of this study is to evaluate the potential use of polyamidoamine (PAMAM) starburst dendrimer (generation 2, G2) conjugates with 6-O-??-(4-O-??-d-glucuronyl)-d-glucosyl-??-cyclodextrin (GUG-??-CDE (G2)) having glucose as a spacer between dendrimer and cyclodextrin (CyD) as a novel gene transfer carrier. GUG-??-CDE (G2) was found to have lower hemolytic activity than dendrimer (G2), suggesting that GUG-??-CDE (G2) had lower local irritation than dendrimer (G2). Of GUG-??-CDEs (G2) having the various average degree of substitution (DS) of a glucuronylglycoside group, GUG-??-CDE (G2, DS 1.8) possessed much higher gene transfer activity than ??-CDE (G2, DS 1.2) and ??-CDE (G2, DS 1.3) in A549 and RAW264.7 cells, suggesting the crucial role of a spacer between dendrimer and CyD for high gene transfer activity of GUG-??-CDE (G2, DS 1.8). In sharp contrast to linear polyethyleneimine (10 kDa, PEI), GUG-??-CDE (G2, DS 1.8) had negligible cytotoxicity. These results suggest that GUG-??-CDE (G2, DS 1.8) could have the potential for a novel gene transfer carrier, compared to ??-CDE (G2, DS 1.2), ??-CDE (G2, DS 1.3) and PEI.     

Ultrathin gate dielectrics for silicon nanodevices

This paper reviews recent progress in structural and electronic characterizations of ultrathin SiO₂thermally grown on Si(100) surfaces and applications of such nanometer-thick gate oxides to advanced MOSFETs and quantum-dot MOS memory devices. Based on an accurate energy band profile determined for the n ⁺ -poly- Si/SiO₂/Si(100) system, the measured tunnel current through ultrathin gate oxides has been quantitatively explained by theory. From the detailed analysis of MOSFET characteristics, the scaling limit of gate oxide thickness is found to be 0.8 nm. Novel MOSFETs with a silicon quantum-dot floating gate embedded in the gate oxide have indicated the multiple-step electron injection to the dot, being interpreted in terms of Coulombic interaction among charged dots.     

Nondissociative chain walking as a strategy in catalytic organic synthesis

“Nondissociative” chain walking is a mechanism where an alkylmetal species undergoes rapid β-hydride elimination and reinsertion to move the metal center along the alkyl chain without dissociating an alkene intermediate during the migration process. This digest summarizes the unique characteristics of the nondissociative chain walking mechanism compared to the stepwise alkene isomerization mechanism and their use in catalytic organic synthesis.     

Metal‐Catalyzed Sequential Formation of Distant Bonds in Organic Molecules: Palladium‐Catalyzed Hydrosilylation/Cyclization of 1,n‐Dienes by Chain Walking

Sequential formation of distant bonds in organic molecules was achieved for the palladium‐catalyzed hydrosilylation/cyclization of various 1,n‐dienes by chain walking of the metal catalyst. The reaction was applicable to various 1,n‐dienes, including a 1,13‐diene, to form a cyclopentane ring as well as a carbon–silicon bond at a remote site. The use of “nondissociative” chain walking provides a fascinating strategy in organic synthesis to functionalize distant parts of organic molecules, in a particular order, within a catalytic cycle by effectively moving the reactive center from a remote position.