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951.
Vladimir V. Tatarchuk Anastasiya P. Sergievskaya Irina A. Druzhinina Vladimir I. Zaikovsky 《Journal of nanoparticle research》2011,13(10):4997-5007
The kinetics of the growth of gold nanoparticles during the reduction of tetrachloroauric acid by hydrazine in dispersed aqueous
solution encapsulated by reverse micelles of Triton N-42 surfactant (with decane as dispersion medium) was studied by means
of spectrophotometry. According to DLS data, at a set value of solubilization capacity V
s/V
o = 0.005 initial micelles have an aqueous core hydrodynamic diameter d
c = 3.6±0.2 nm. The final particles obtained after full reduction of AuIII have a metallic core of defect-free single-crystalline gold with a narrow size distribution and average core diameter d
Au = 7.7 ± 1.4 nm as shown by TEM. The rate of the particle growth is limited by the rate of gold reduction. The process kinetics
corresponds to the model consisting of two stages of reduction AuIII → AuI → Au0. The stages involve the formation and redox decay of the intermediate complexes Au(N2H4)Cl3 and Au(N2H4)Cl, and each stage proceeds via two routes: (1) homogeneous in the dispersed aqueous phase, and (2) heterogeneous on the
particle surfaces. Reactions taking route (2) are autocatalytic because they proceed with participation of the surface atoms
of particles as the final products of AuIII reduction. The dependencies of observed rate constants on reagent concentrations, temperature, and solubilization capacity
of the micellar solution are studied. 相似文献
952.
Olga N. Glotova Irina P. Korneva Nikolay Ya. Sinyavsky Bernadeta Dobosz Ryszard Krzyminiewski Maciej Jadzyn Michal Ostafin Boleslaw Nogaj 《Central European Journal of Physics》2011,9(2):387-391
In this paper experimental results obtained by both 75As NQR and EPR spectroscopy are presented for the three-component system As-Sb-Se. The 75As NQR spectra of glasses of structures (As2Se3)0.78 (Sb2Se3)0.22, (As2Se3)0.75 (Sb2Se3)0.25, (As2Se3)0.5 (Sb2Se3)0.5 have broad lines with two Sb-NQR lines (corresponding to the Sb2Se3 units) and two 75As-NQR lines (corresponding to the As2Se3 units). Differences in the EPR spectra of the different glasses arise because of the different amounts of arsenic and antimony
in their structure. 相似文献
953.
Dr. Nataliya V. Maksimchuk Dr. Irina D. Ivanchikova Dr. Kyung Ho Cho Dr. Olga V. Zalomaeva Dr. Vasiliy Yu. Evtushok Kirill P. Larionov Dr. Tatiana S. Glazneva Prof. Jong-San Chang Prof. Oxana A. Kholdeeva 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(23):6985-6992
The catalytic performance of Zr-abtc and MIP-200 metal–organic frameworks consisting of 8-connected Zr6 clusters and tetratopic linkers was investigated in H2O2-based selective oxidations and compared with that of 12-coordinated UiO-66 and UiO-67. Zr-abtc demonstrated advantages in both substrate conversion and product selectivity for epoxidation of electron-deficient C=C bonds in α,β-unsaturated ketones. The significant predominance of 1,2-epoxide in carvone epoxidation, coupled with high sulfone selectivity in thioether oxidation, points to a nucleophilic oxidation mechanism over Zr-abtc. The superior catalytic performance in the epoxidation of unsaturated ketones correlates with a larger amount of weak basic sites in Zr-abtc. Electrophilic activation of H2O2 can also be realized, as evidenced by the high activity of Zr-abtc in epoxidation of the electron-rich C=C bond in caryophyllene. XRD and FTIR studies confirmed the retention of the Zr-abtc structure after the catalysis. The low activity of MIP-200 in H2O2-based oxidations is most likely related to its specific hydrophilicity, which disfavors adsorption of organic substrates and H2O2. 相似文献
954.
955.
Chelnokova Irina A. Golubewa L. N. Starodubtseva M. N. Kulahava T. A. Kunitskaya Y. N. Bulai P. M. Starodubtsev I. E. Kharin Yu. S. Shuba M. V. 《Journal of nanoparticle research》2020,22(6):1-16
Journal of Nanoparticle Research - Benefited from their broad-spectrum antimicrobial property, silver nanoparticles (AgNPs) have been widely used in various daily life and medical products.... 相似文献
956.
957.
958.
Tatiana N. Rudneva Olga S. Zhukova Gennady V. Shilov Irina O. Chikileva Michael V. Kisilevskii Nataliya A. Sanina 《Journal of Coordination Chemistry》2019,72(5-7):972-986
Single-crystals of binuclear neutral sulfur-nitrosyl iron complex with 2-mercaptobenzthiazole ligand [Fe2(С7н4NS2)2(NO)4] (BTz) have been obtained. From X-ray data, BTz has a centrosymmetric dimeric structure, with the iron atoms being linked through the µ-N-C-S bridge. As follows from mass-spectra of the BTz gas phase, the complex is stable in the crystalline state under normal conditions (ambient temperature and standard humidity) and releases nitric oxide upon heating. Using amperometry, kinetics of NO release by BTz in 1% dimethyl sulfoxide aqueous solution has been studied: release of NO was shown to occur immediately upon dissolution in protic media. BTz inhibited growth of K562 leukemia and SKOV3 ovarian carcinoma cells in vitro and induced apoptosis via activation caspases 3 and 7. 相似文献
959.