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Optical Review - To evaluate multi-spectral images of the absorption and scattering properties in the cerebral cortex of rat brain, we investigated spectral reflectance images estimated by the...  相似文献   
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Organocatalytic enantioselective aza‐Friedel–Crafts reactions of cyclic ketimines with pyrroles or indoles were catalyzed by imidazoline/phosphoric acid catalysts. The reaction was applied to various 3H‐indol‐3‐ones to afford products in excellent yields and enantioselectivities. The chiral catalysts can be recovered by a single separation step using column chromatography and are reusable without further purification. Based on the experimental investigations, a possible transition state has been proposed to explain the origin of the asymmetric induction.  相似文献   
4.
Purity assay of high-purity materials (HPMs) of phthalic acid esters (PAEs) was carried out by means of a mass balance method. In this method, chromatographic methods such as gas chromatography-flame ionization detector (GC-FID) and/or high-performance liquid chromatography (HPLC) in combination with other methods such as Karl-Fischer (KF) titration and vacuum evaporation (VE) were applied. The sum of the impurities estimated by these methods allowed the estimation of the purity of the main component by difference. Seven PAEs with varying side chain structures and levels of impurities were analysed on a systematic way in which impurities were classified into several groups in terms of their abundance, availability of qualitative information and availability of authentic compounds, etc. The absolute quantity of each impurity was determined by GC-FID and/or HPLC based on the calibration made by the authentic compounds of impurities whenever available. The purities in mass fraction of these PAEs were certified at the National Metrology Institute of Japan (NMIJ), and the PAEs were registered as primary reference materials playing an essential role in linking the metrological traceability of the Japan Calibration Service System (JCSS) to the International System of Units (SI).  相似文献   
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The assembly of metal oxide nanoparticles (NPs) on a biomolecular template by a one-pot hydrothermal synthesis method is achieved for the first time. Magnetite (Fe3O4) nanoneedles (length: ~100 nm; width: ~10 nm) were assembled on cyclic-diphenylalanine (cFF) nanorods (length: 2–10 μm; width: 200 nm). The Fe3O4 nanoneedles and cFF nanorods were simultaneously synthesized from FeSO4 and l-phenylalanine by hydrothermal synthesis (220 °C and 22 MPa), respectively. The samples were analyzed by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (IR), transmission electron microscopy (TEM), and superconducting quantum interference device (SQUID) magnetometry. Experimental results indicate that Fe3O4 nanoneedles were assembled on cFF nanorods during the hydrothermal reaction. The composite contained 3.3 wt% Fe3O4 nanoneedles without any loss of the original magnetic properties of Fe3O4.  相似文献   
6.
An enantioselective three‐component reaction of aldehydes, amines, and alkynes in water by using a bis(imidazoline)–CuI catalysts having a hydrophobic substituent and sodium dodecyl sulfate as a surfactant was developed. The reaction was applied to a broad range of aldehydes and alkynes to give optically active propargylamines with excellent yields (up to 99 %) and enantiomeric excesses (up to 99 % ee).  相似文献   
7.
Five macrocyclic molecules (15) were efficiently synthesized from the dimerization and trimerization of di-substituted adamantane derivatives, which were composed of three different aromatic units and two different linker groups. Three single-crystals were obtained from these macrocyclic molecules, including a set of pseudopolymorphs (3a and 3b) of macrocycle 3 and another macrocycle 5 (5a). Single crystal X-ray analysis revealed that the three monocyclic compounds were rectangular or square in shape with solvent molecules in the cavity. Macrocycle 3 in 3a formed stacks to produce tubular structures with channels that assembled into three-dimensional networks through CH/π interactions.  相似文献   
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A pilot-scale pulse corona induced plasma chemical process (PPCP) reactor for controlling gas-phase dioxins and NO x simultaneously is installed in a garbage incineration plant. The flow rate of the sampled flue gas is 5,000 Nm3/h (N: standard state) in maximum at the PPCP reactor, which consists of 22 wire-cylinder electrodes and is energized by a 50 kW nanosecond pulse high voltage generator. With an applied plasma energy density of 2.9–6.1 Wh/Nm3, the decomposition efficiency for dioxins is 75–84% based on TEQ (toxic equivalents); the conversion efficiency of NO to NO2 is ~93% at maximum. The flue gas treated by the PPCP reactor is introduced at a rate of 50 Nm3/h to a wet-type chemical reactor, which uses an aqueous solution of sodium sulfite (Na2SO3). More than 90% of NO x is reduced to nitrogen, with negligible byproducts such as NO2 or NO3 ions left in the solution.  相似文献   
9.
Here, a quantitative electrochemical analysis of periodontal bacteria in gingival crevicular fluid (GCF) and saliva by direct polymerase chain reaction (PCR) is presented. The electrochemical measurement was performed by mixing with PCR products and electrochemical indicator (bisbenzimidazole trihydrochloride). The peak current of indicator is reduced due to slower diffusion when the dye intercalates into the amplified DNA, and the degree of reduction in the peak current is correlates with the quantity of amplified DNA. Therefore, a quantitative analysis is possible by using our electrochemical method at the end point of PCR. In the GCF testing, The number of Porphyromonas gingivalis (Pg) detected by our electrochemical method at the end point of PCR were almost same compared with that were calculated by the conventional method of quantitative real? time PCR. In the saliva testing, the relationship between number of Pg in saliva and average pocket depth, and age‐dependence were also clearly observed. Since the saliva sample is obtained in a non‐invasive manner, this method is useful for the primary screening of periodontal disease. Moreover, our detection method is simple and uses a hand‐held potentiostat making it suitable for development of an on‐site periodontal diagnosis system.  相似文献   
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