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971.
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974.
The stability constans, 1, of each monochloride complex of Eu(III) have been determined in the methanol and water mixed system with 1.0 mol·dm–3 ionic strength using a solvent extraction technique. The values of 1 increase with an increase in the mole fraction of methanol (X S ) in the mixed solvent system when 0X S 0.40. The, distance of Eu3+–Cl in the mixed solvent system was calculated using the Born-type equation and the Gibbs' free energy derived from 1. Calculation of the Eu3+–Cl distance and the preferential solvation, of Eu3+ by water proposed the variation of the outersphere complex of EuCl2+ as follows: (1) [Eu(H2O)9]3+Cl, [Eu(H2O)8]3+Cl and [Eu(H2O)7(CH3OH)3+Cl inX S0.014, (2) [Eu(H2O)8]3–Cl and [Eu(H2O)7(CH3OH)]3+Cl in 0.014<X S <0.25 and (3) [Eu(H2O)7(CH3OH)]3–Cl and [Eu(H2O)6(CH3OH)[2 3+Cl in 0.25<X S 0.40.  相似文献   
975.
Different from works described in the literature, which use expansive analytical methods to separation of anthraquinones derivatives (AQs), this communication reported a simple and inexpensive methodology to get them. In this way, the expensive commercial AQs: Chrysophanol, physcione and emodine were extracted from plant material (Rhamnus frangula L.) and isolated by classical column chromatography technique under optimised binary mobile phase gradients (CHCl3 : AcOEt(a), a = 1 to 5%) in excellent yields.  相似文献   
976.
A cationic fluorescent nanogel thermometer based on thermo‐responsive N‐isopropylacrylamide and environment‐sensitive benzothiadiazole was developed with a new azo compound bearing imidazolium rings as the first cationic radical initiator. This cationic fluorescent nanogel thermometer showed an excellent ability to enter live mammalian cells in a short incubation period (10 min), a high sensitivity to temperature variations in live cells (temperature resolution of 0.02–0.84 °C in the range 20–40 °C), and remarkable non‐cytotoxicity, which permitted ordinary cell proliferation and even differentiation of primary cultured cells.  相似文献   
977.
978.
This paper describes effect of base profile for precise measurement of photon energy in prompt -ray analysis (PGA). The base profile has been examined in the vicinity of full energy (FE), single escape and double escape peaks. Major origins of step-wise base profiles are single and double escape events for triple photon annihilation and single and double Compton escape events for double photon annihilation in the detector, in addition to general events for the FE peak. A formula has been proposed for the quantitative characterization of the base profile.  相似文献   
979.
980.
We propose a method for three-dimensional microfabrication with photopolymerization stimulated by two-photon absorption with a pulsed infrared laser. An experimental system for the microfabrication has been developed with a Ti:sapphire laser whose oscillating wavelength and pulse width are 790 nm and 200 fs, respectively. The usefulness of the proposed method has been verified by fabrication of several kinds of microstructure by use of a resin consisting of photoinitiators, urethane acrylate monomers, and urethane acrylate oligomers.  相似文献   
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