排序方式: 共有34条查询结果,搜索用时 15 毫秒
1.
V Correcher J Garcia-Guinea FJ Valle-Fuentes 《Journal of Thermal Analysis and Calorimetry》2006,83(2):439-444
In
this paper, novel results on the blue thermally stimulated luminescence (TSL)
emission of ulexite (NaCaB5O6(OH)6·5H2O)
have been studied. The four maxima appearing at 60, 110, 200 and 240°C
on the TSL glow curves of this borate could be respectively associated to:
(i) the first dehydration (NaCaB5O6(OH)6·5H2O→NaCaB5O6(OH)6·3H2O),
(ii) the creation-annihilation of the three-hydrated
phase, (iii) the Na-coordinated chains
dehydroxylation and the starting point of the alkali self-diffusion through
the lattice and (iv) the amorphisation
of the lattice. These results are fairly well correlated with the differential
thermal analyses (DTA), in situ thermal observations under environmental scanning
electron microscope (TESEM) and thermal X-ray diffraction (TXRD) techniques. 相似文献
2.
3.
4.
5.
6.
Jiann-Kuan Luo Ronald F. Federspiel Raymond N. Castle 《Journal of heterocyclic chemistry》1995,32(2):659-664
The synthesis of two previously unknown polycyclic heterocyclic ring systems via photocyclization is described. The unequivocal assignment of their proton and carbon spectra was achieved by utilizing two-dimensional nmr techniques. 相似文献
7.
Franz Ganster Jukius Höttinger Norbert Müller Per Federspiel Martin Potschka Margit Schlederer Peter Wolschann 《Monatshefte für Chemie / Chemical Monthly》1986,117(10):1145-1156
A laboratory microcomputer system based on an APPLE II microcomputer is presented. Data transfer from a temperature jump equipment or a stopped flow apparatus can be performed via a serial interface, the data can be stored on a memory expansion card or on the disk drives. Data transfer to a central host computer can also be done. Application of the laboratory data system on kinetic and spectroscopic measurements are shown.Dedicated to Prof. Dr.K. L. Komarek on the occasion of his 60th birthday. 相似文献
8.
9.
Jiann-Kuan Luo Ronald F. Federspiel Raymond N. Castle 《Journal of heterocyclic chemistry》1997,34(5):1597-1601
Photocyclization of 3-chloro-N-(3-phenanthryl)thieno[2,3-b]thiophene-2-carboxamide ( 5 ) yielded only one of the two possible structural isomers, thieno[3′,2′:4,5]thieno[2,3-c]naphtho[1,2-f]quinolin-6(5H)-one ( 6 ), which was further elaborated to afford the unsubstituted ring system 10 , its triazole 11 and tetrazole 12 . The structural confirmation of 10 was achieved by the total assignment of its 1H and 13C nmr spectra by the concerted utilization of two-dimensional nmr spectroscopic methods. 相似文献
10.
Fernández-Ibáñez P de las Nieves FJ Malato S 《Journal of colloid and interface science》2000,227(2):510-516
Electron transfer between a titanium dioxide/electrolyte solution interface has been studied. As found by other researchers of similar interfaces (TiO(2)- and ZnO-electrolyte solution), a slow consumption of OH(-) ions takes place in this type of interface. A theoretical model has been developed for calculating the change in the Fermi energy of both electrolyte solution and semiconductor, showing that ion consumption from the solution is favoured by the decrease of the difference between their Fermi energies. A kinetic constant (upsilon) is found to characterise the consumption process, its value increasing with electrolyte and semiconductor mass concentrations. Furthermore, this process may be used to estimate the point of zero charge of a titanium dioxide colloidal dispersion. Copyright 2000 Academic Press. 相似文献