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Six reducing monosaccharides (mannose, galactose, fucose, glucose, xylose, and arabinose) were derivatized with 8-aminonaphthalene-1,3,6-trisulfonate (ANTS). Based on the chiral ligand-exchange principle using borate as a central ion of the chiral selector and (S)-3-amino-1,2-propanediol (SAP) as a chiral selector ligand, all of the six ANTS-monosaccharides were simultaneously enantioseparated using absorbance at 245 nm for detection. The optimum conditions for both high resolution and moderately short migration time consisted of 200 mM SAP-200 mM borate buffer (pH 9.2) containing 10% ACN as a BGE at 30 degrees C with an applied voltage of +30 kV. It was revealed that the proposed chiral ligand-exchange CE using the SAP-borate system was applicable to enantioseparation of not only diols but also polyols.  相似文献   
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The oxidative coupling of 2-naphthol and 3-hydroxy-2-naphthoate derivatives with a copper catalyst under an O2 atmosphere was carried out. The reaction in the presence of a catalytic amount of the Lewis acid, Yb(OTf)3, proceeded in a cross-coupling specific manner.  相似文献   
44.
There is broad interest in molecular encapsulation as such systems can be utilized to stabilize guests, facilitate reactions inside a cavity, or give rise to energy‐transfer processes in a confined space. Detailed understanding of encapsulation events is required to facilitate functional molecular encapsulation. In this contribution, it is demonstrated that Ir and Rh‐Cp‐type metal complexes can be encapsulated inside a self‐assembled M6L4 metallocage only in the presence of an aromatic compound as a second guest. The individual guests are not encapsulated, suggesting that only the pair of guests can fill the void of the cage. Hence, selective co‐encapsulation is observed. This principle is demonstrated by co‐encapsulation of a variety of combinations of metal complexes and aromatic guests, leading to several ternary complexes. These experiments demonstrate that the efficiency of formation of the ternary complexes depends on the individual components. Moreover, selective exchange of the components is possible, leading to formation of the most favorable complex. Besides the obvious size effect, a charge‐transfer interaction may also contribute to this effect. Charge‐transfer bands are clearly observed by UV/Vis spectrophotometry. A change in the oxidation potential of the encapsulated electron donor also leads to a shift in the charge‐transfer energy bands. As expected, metal complexes with a higher oxidation potential give rise to a higher charge‐transfer energy and a larger hypsochromic shift in the UV/Vis spectrum. These subtle energy differences may potentially be used to control the binding and reactivity of the complexes bound in a confined space.  相似文献   
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We proposed in this research a novel two-dimensional network based on the frog visual system, with a motion detection function and a newly developed simple-shape recognition function, for use in object discrimination by integrated circuits. Specifically, the network mimics the signal processing of the small-field cell in a frog brain, consisting of the tectum and thalamus, which generates signals of the motion and simple shape of an object. The proposed network is constructed from simple analog complementary metal oxide semiconductor (CMOS) circuits; a test chip of the proposed network was fabricated with a 1.2 μm CMOS process. Measurements on the chip clarified that the proposed network can generate signals of the moving direction, velocity, and simple shape, as well as perform information processing of the small-field cell. Results with the simulation program with integrated circuit emphasis (SPICE) showed that the analog circuits used in the network have low power consumption. Applications of the proposed network are expected to realize advanced vision chips with functions such as object discrimination and target tracking.  相似文献   
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Ohtera  Yasuo  Sato  Airi  Kawashima  Takayuki  Takaya  Tomohisa  Okura  Yuki 《Optical Review》2022,29(2):140-152
Optical Review - Multi-spectral filter array composed of a wavy alternating dielectric multilayer was integrated on a CMOS image sensor of the Raspberry Pi HQ Camera. The filter array consists of...  相似文献   
49.
We here demonstrate the creation of novel poly(aniline) (PANI) nanofiber structures by a polymer wrapping method using schizophyllan (SPG). Mannose-modified SPG can also wrap PANIs to give nanofibers having a lectin affinity. This interaction is applicable to designing novel PANI/protein composites. The results establish that SPG can act as a novel "host" to assemble PANIs into one-dimensional superstructures. [reaction: see text]  相似文献   
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Single-walled carbon nanotubes can be entrapped within a helical superstructure composed of schizophyllan bearing lactoside-appendages to show an excellent water-solubility as well as a specific lectin-affinity.  相似文献   
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