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101.
Secondary amines react with carbon disulphide to form stable dialkyldithiocarbamates at high pH in aqueous Triton X-100 solution. The formation rates of dimethyl-, diethyl-, di-n-propyl-, diisopropyl-, di-n-butyl- and diisobutyldithiocarbamates and pyrrolidinedithiocarbamate were measured by a stopped-flow spectrophotometric method. The reaction rates were a function of the pH of the solution and depended on the size and structure of the amines. The rate of isoalkylamines was far slower than that of the n-alkyl analogues. Individual concentrations of amines were determined in a mixture of di-n- and diisopropylamine and in a mixture of diiso- and di-n-butylamine. 相似文献
102.
Koji Ishida Yoshiaki Uchida Shuji Ninomiya Masumi Osawa 《Fresenius' Journal of Analytical Chemistry》1990,336(5):419-422
Summary The thin-layer chromatographic behaviour of all the rare earths except Pm on silica gel in aqueous solutions of five alkali metal chlorides has been surveyed. The Rf-values and the logarithms of the separation factors relative to Gd vary in a regular and peculiar way with increasing atomic number, through a reflection of the strong tetrad effect. A discussion concerning the effects on the Rf-values of the solvent cations and the solvent anions, and typical chromatograms for the separations of multi-component mixtures containing adjacent lanthanoids are also presented. 相似文献
103.
Koji Nonaka Hidehiko Takara Atsushi Takada Kentaro Uchiyama Yoshiaki Yamabayashi 《Optical Review》1998,5(6):331-333
An optical mono-stable multivibrator laser diode (MM-LD) is realized by using a multi-electrode distributed feedback laser diode. All-optical pulse-width conversion of ultra-short pulses to non-return-to-zero (NRZ) is achieved using an MM-LD. The MM-LD is adopted for a wide range of bit-rates between 2-10 Gbit/s by tuning the DC bias. Data format transformation from 10-Gbit/s return-to-zero optical signals to NRZ optical-signals is achieved with error free operation. Converted optical signals, which have a narrower spectral bandwidth and lower peak power than when input, are transmitted using a 1.3-μm zero dispersion fiber (1.3Aλ0-SMF). 相似文献
104.
Takahito Itoh Motoka Ikeda Nobuyuki Hirata Yuji Moriya Zhaoyin Wen Yoshiaki Ichikawa Masataka Kubo Osamu Yamamoto 《Ionics》2002,8(1-2):44-52
Terminal-acetylated hyperbranched poly(ethylene glycol) derivatives containing diethylene, triethylene, and hexaethylene and
3,5-dioxybenzoate branching units (poly-Ac1a, poly-Ac1b, and poly-Ac1c) were synthesized. Electrochemical and thermal properties of the hyperbranched polymer electrolytes with lithium salts such
as LiCF3SO3 and LiN(CF3SO2)2, the composite hyperbranched polymer electrolytes with LiN(CF3SO2)2 containing α-LiAlO2 and γ-LiAlO2 fillers, and the hyperbranched polymer blended poly(ethylene oxide) electrolytes with LiN(CF3SO2)2 were investigated and discussed.
Paper presented at the 8th EuroConference on Ionics, Carvoeire, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
105.
Eriko KagiNobuyuki Yamamoto Hisashi FujiwaraMasaru Fukushima Takashi Ishiwata 《Journal of Molecular Spectroscopy》2002,216(1):48-51
Optical-optical double resonance spectroscopy was used to study the 1g(3P1) ion-pair state of I2 correlating to I−(1S)+I+3P1) at the dissociation limit. We gained access to the 1g(3P1) state though the A3Π (1u) state in the (1+1) photon-excitation scheme. The pump laser excited the A3Π (1u)-X1Σg+ transition at a fixed frequency for state selection. The probe laser was scanned to detect the 1g(3P1)-A3Π (1u) resonance by monitoring the ultraviolet emission from the 1g(3P1) state at 278 nm. The 1g(3P1) state was observed in a vibrational progression consisting of P and R doublets. An energy level analysis was carried out for the 1g(3P1) state in the 0≤ v ≤ 14 and 12≤J≤135 range, which led to a set of molecular parameters including the Ω-doubling constant. The Ω-doubling of the 1g(3P1) state was discussed by the pure precession model and interpreted to occur through the heterogeneous coupling with the 0g−(3P1) state correlating to the same ionic asymptote. 相似文献
106.
Equivalence of the generalized complementarity problem to differentiable unconstrained minimization 总被引:4,自引:0,他引:4
We consider an unconstrained minimization reformulation of the generalized complementarity problem (GCP). The merit function introduced here is differentiable and has the property that its global minimizers coincide with the solutions of GCP. Conditions for its stationary points to be global minimizers are given. Moreover, it is shown that the level sets of the merit function are bounded under suitable assumptions. We also show that the merit function provides global error bounds for GCP. These results are based on a condition which reduces to the condition of the uniform P-function when GCP is specialized to the nonlinear complementarity problem. This condition also turns out to be useful in proving the existence and uniqueness of a solution for GCP itself. Finally, we obtain as a byproduct an error bound result with the natural residual for GCP.We thank Jong-Shi Pang for his valuable comments on error bound results with the natural residual for the nonlinear complementarity problem. We are also grateful to the anonymous referees for some helpful comments. The research of the second author was supported in part by the Science Research Grant-in-Aid from the Ministry of Education, Science, and Culture, Japan. 相似文献
107.
Akito Kobayashi Yoshiaki
no Tamifusa Matsuura Yoshihiro Kuroda 《Physica C: Superconductivity and its Applications》1998,300(3-4):287-300
Dynamical spin susceptibility χs(q,ω) of the d–p model in the over doping region is investigated by using the auxiliary boson technique. It includes higher order terms of the 1/N-expansion within the random phase approximation (RPA) of the local vertex, where frequency dependence of the quasi-particle interaction is taken into account. The incommensurate spin fluctuation is obtained due to the nesting effect in the low energy region (ωω*), whereas the commensurate one in the high energy region (ωω*), the characteristic energy ω* is estimated to be about 30 meV. Both of the spin–lattice relaxation rate 1/T1 and the spin–spin relaxation rate 1/Tg monotonically increase as T decreases, while the spin Knight shift K is almost independent of T. 相似文献
108.
Naoto Sugimoto Seiji Fukushima Yasuhiro Suzuki Yoshihisa Sakai Hiromasa Tanobe Takeshi Kurosaki Kazuto Noguchi Kimio Oguchi Hiromu Toba 《光学学报》2003,23(Z1)
A new generation of network interface card for fiber-to-the-desktop has been fabricated. The fabricated card is PC-card size and suitable for notebook PCs. It could become the key element in the coming optical Ethernet age. 相似文献
109.
Jun Zhe Min Toshimasa Toyooka Hiroki Kawanishi Takeshi Fukushima Masaru Kato 《Analytica chimica acta》2005,550(1-2):173-181
Several fluorescent asparaginyl-N-acetyl-d-glucosamines (Asn-GlcNAcs), i.e., DBD-Asn-GlcNAc, NBD-Asn-GlcNAc, NDA-Asn-GlcNAc, PS-Asn-GlcNAc, FITC-Asn-GlcNAc, DMEQ-Asn-GlcNAc and DBD-PZ-Boc-Asn-GlcNAc, were synthesized as the acceptors for the resolution of oligosaccharides in glycopeptides. The resolution of oligosaccharides is based on the transglycosylation reaction with end-β-N-acetylglucosaminidase (Endo-M), isolated from Mucor hiemalis. The synthesis of each fluorescent acceptor was carried out in a one-pot reaction of Asn-GlcNAc and the corresponding fluorescent tagging reagent. The transglycosylation reaction using Endo-M proceeds at RT in neutral phosphate buffer (pH 6.0) and reached maxima at around 30 min. When Fmoc-Asn-GlcNAc (acceptor) was enzymatically reacted with Disialo-Asn (donor) in the presence of Endo-M, the ratio of Disialo-Asn-Fmoc (transglycosylation product) was almost comparable with the decreasing ratio of Fmoc-Asn-GlcNAc. Therefore, the transglycosylation activity of Endo-M from Disialo-Asn (donor) and fluorescent-Asn-GlcNAc (acceptor) was calculated from the decreasing ratio of fluorescent-Asn-GlcNAc. The order was NDA-Asn-GlcNAc > DBD-Asn-GlcNAc Fmoc-Asn-GlcNAc > NBD-Asn-GlcNAc DMEQ-Asn-GlcNAc > DNS-Asn-GlcNAc > PS-Asn-GlcNAc > FITC-Asn-GlcNAc. On the other hand, the activity with a fluorescent acceptor (DBD-PZ-Boc-Asn-GlcNAc), labeled to a carboxylic acid group in the Asn residue, was the strongest among the synthesized acceptors. 相似文献
110.
Hidehito Nanto Fumitaka Endo Yoshiaki Hirai Shouichi Nasu Nozomu Takeuchi 《Optical Review》1994,1(2):177-179
Intense photostimulated luminescence (PSL) with a peak at 420 nm is observed in ultraviolet (UV) Iight-irradiated europium-doped potassium chloride (KCl: Eu) crystalline phosphors. The PSL characteristics of UV-irradiated KCl: Eu phosphor for optical memory application were studied. The excitation and emission mechanisms of the 420 nm PSL, which are consistent with the results obtained, are discussed. 相似文献