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1.
Mechanism of gold adsorption by persimmon tannin gel. 总被引:1,自引:0,他引:1
Gold adsorption by persimmon tannin (PT) gel from a solution containing hydrogen tetrachloroaurate(III) was examined. A flow-rate examination in a column system indicated the reduction of Au(III) ion to Au(0). XRD patterns clarified the existence of Au(0) on the gel which adsorbed gold. The gel could also adsorb colloidal Au(0) prepared independently. A model consisting of ligand exchange, Au(III) reduction to Au(0), and resulting Au(0) adsorption by PT gel was presented for the gold adsorption mechanism. 相似文献
2.
3.
Haru Ogawa Yoshinari Taketugu Taiji Imoto Yōichi Taniguchi Hidefumi Kato 《Tetrahedron letters》1979,20(36):3457-3460
Rearrangement of 2,4-di--pentadienals was described as a consequence of the successive alkyl substitutions on the C-2 and C-4 positions. 1H-FT nmr spectroscopy suggested that the reaction involves ketene as an intermediate. 相似文献
4.
Tetsuo Yamasaki Yuji Yoshihara Yoshinari Okamoto Tadashi Okawara Mitsuru Furukawa 《Journal of heterocyclic chemistry》1992,29(5):1313-1316
The reaction of 5-hydrazinopyridazin-3(2H)-ones 1 with α-keto diester 2 in acetic acid afforded the corresponding 4,6-dihydropyridazino[4,5-c]pyridazin-5(1H)-ones 3 and pyrrolo[2,3-d)pyridazin-4(5H)-ones 4 . Compounds 3 were also obtained from 4-bromo-5-hydrazinopyridazin-3(2H)-ones 8 and 2 under milder conditions. 5-Bromo-4-hydrazinopyridazin-3(2H)-one 9 , the regioisomer of 8b , also reacted readily with 2a to give 4,7-dihydropyridazino[4,5-c]pyridazin-8(1H)-one 10b , the regioisomer of 3b . 相似文献
5.
Katsuya Oji Asako Igashira‐Kamiyama Nobuto Yoshinari Takumi Konno 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(7):2023-2027
A novel AuICoIII coordination system that is derived from the newly prepared [Co(D ‐nmp)2]− ( 1 −; D ‐nmp=N‐methyl‐D ‐penicillaminate) and a gold(I) precursor AuI is reported. Complex 1 − acts as a sulfur‐donating metallaligand and reacts with the gold(I) precursor to give [Au2Co2(D ‐nmp)4] ( 2 ), which has an eight‐membered AuI2CoIII2 metallaring. Treatment of 2 with [Au2(dppe)2]2+ (dppe=1,2‐bis(diphenylphosphino)ethane) leads to the formation of [Au4Co2(dppe)2(D ‐nmp)4]2+ ( 3 2+), which consists of an 18‐membered AuI4CoIII2 metallaring that accommodates a tetrahedral anion (BF4−, ClO4−, ReO4−). In solution, the metallaring structure of 3 2+ is readily interconvertible with the nine‐membered AuI2CoIII metallaring structure of [Au2Co(dppe)(D ‐nmp)2]+ ( 4 +); this process depends on external factors, such as solvent, concentration, and nature of the counteranion. These results reveal the lability of the Au S and Au P bonds, which is essential for metallaring expansion and contraction. 相似文献
6.
Tsuji S Yoshinari Y Kawai E Nakajima K Park HS Shindo D 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2007,188(2):380-386
A new method of surface microscopy is proposed, which combines three-dimensional electron spin resonance imaging by magnetic resonance force microscopy (MRFM) and topographic imaging of the sample surface by scanning force microscopy (SFM). In order to demonstrate its potential for the identification of microscale objects, the individual and combined images are used to provide the locations, shapes and spin density distributions of target phantom objects. We report spatial resolution in MRFM of 2.8 x 2.8 x 2.0 microm(3). This could be improved to the theoretical limit of 0.08 x 0.08 x 0.04 microm(3) through reduction of the thermal noise by cooling to cryogenic temperatures approximately 0.5K. We believe that this type of microscopy will become a very useful tool for the investigation of anomalies induced in surfaces by materials buried below the surface. 相似文献
7.
It was tried to prepare hybrid microcapsules composed of porous inorganic particles and epoxy resin shell and to apply to the self‐healing agent. A water soluble imidazole of gelation promoting agent as the core material was microencapsulated in the porous inorganic particles, which were coated with epoxy resin. The porous inorganic particles were prepared with the interfacial reaction between sodium silicate and calcium ion in the (W/O) dispersion. In the experiment, the concentration of sodium silicate and the mixing speed to form the (W/O) dispersion were mainly changed. The porous inorganic particles were immersed in the aqueous solution dissolving imidazole and then, added in the corn oil dissolving epoxy resin to be microencapsulated with gelated epoxy resin. The hybrid microcapsules containing imidazole with the mean diameters from 200 to 400 µm were able to be prepared and to induce the gelation reaction of epoxy resin by breaking the hybrid microcapsule shell due to heating. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
8.
Kento Imanishi Benny Wahyudianto Dr. Tatsuhiro Kojima Dr. Nobuto Yoshinari Prof. Takumi Konno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(8):1827-1833
Here a unique single-crystal-to-single-crystal (SCSC) transformation of a 116-nuclear AuI72CdII40NaI4 cage-of-cage ( 2 CdNa) is reported, which was created from a trigold(I) metalloligand with d -penicillamine by way of a 9-nuclear AuI6CdII3 cage ( 1 ). Cage-of-cage 2 CdNa is composed of 12 cages of 1 that are linked by 4 Cd2+ and 4 Na+ ions, with its surface being covered by 12 NO3− ions to form a discrete, spherical molecule with a diameter ca. 4.7 nm. In crystal 2 CdNa, the cage-of-cage molecules are packed in a cubic lattice with a huge cell volume of ca. 4.5×105 Å3, so as to have large interstices with diameters of more than 3 nm. Upon soaking crystals 2 CdNa in aqueous Cu(NO3)2, all Cd2+ and Na+ were quickly exchanged by Cu2+ to produce an analogous AuI72CuII44 cage-of-cage ( 2 Cu) in a SCSC manner. Prolonged soaking led to the SCSC transformation to another supramolecular structure ( 2′ Cu) consisting of 152-nuclear AuI72CuII80 cage-of-cages that are alternately H-bonded with the AuI72CuII44 cage-of-cages. 2′ Cu showed the accommodation of MoO42− and the conversion of MoO42− to β-Mo8O264− in the crystal, with retention of single-crystallinity. 相似文献
9.
Metallosupramolecular Structures Derived from a Series of Diphosphine‐bridged Digold(I) Metalloligands with Terminal d‐Penicillamine 下载免费PDF全文
In this report, we describe our recent work on the development of a new family of chiral heteroleptic digold(I) metalloligands with mixed diphosphine and d ‐penicillaminate (d ‐pen), [Au2(dppx)(d ‐pen‐S)2]2– (dppx = PPh2(CH2)nPPh2, n = 1–5) and their application for the construction of chiral multinuclear and metallosupramolecular structures. The reactions of the metalloligands with 3d metal ions produce a variety of chiral heterobimetallic structures retaining the digold(I) metalloligand structure, ranging from discrete trinuclear to infinite helix structures that depend on the type of dppx. In addition, monophosphine and triphosphine analogues of the metalloligands were designed, and their coordination behavior is discussed to show the essential properties and potential extensibility of this class of metalloligands. 相似文献
10.
We present accurate experimental measurements of the lifetimes of rovibrational levels of the long-range H1Sigmag+ state for both D2 and H2, obtained directly from the observation of the time-dependent decay of the fluorescence from these excited levels. These results improve upon and extend those of Reinhold et al. [J. Chem. Phys. 112, 10754 (2000)]. Several decay pathways are open to these levels including fluorescence, predissociation, and autoionization. We present theoretical results for each of these processes, each calculated using the simplest but still appropriate level of theory. In particular, the theoretical calculations provide a quantitative explanation of the dramatic vibrational dependence of the observed lifetimes, the isotope dependence of the lifetimes for levels well localized within the H potential well and therefore not subject to significant tunneling, and an insight into the role of enhanced tunneling in autoionization. In these calculations each of the rovibrational levels of the H state is treated individually, without having to engage in a global coupled-state calculation. 相似文献