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11.
Why carry out medicinal chemistry at a university, when it means competing with the billion-dollar research efforts of the pharmaceutical industry? In academic research, the race to get a drug to market is not the prime motivation. Instead, university-based medicinal chemistry is driven by the search for new knowledge and the opportunity to educate a new generation of chemists. Furthermore, academia can complement commercial efforts by addressing diseases neglected by private industry. 相似文献
12.
Cardinali F Mamlouk H Rio Y Armaroli N Nierengarten JF 《Chemical communications (Cambridge, England)》2004,(14):1582-1583
A multicomponent array made of a bis-copper(I) helicate core and two peripheral fullerene subunits has been prepared and electron transfer from the photoexcited Cu(I)-complexed unit to C60 occurs. 相似文献
13.
The 2-Phenyl-4,5-dimethylphosphorin P-W(CO)5 complex reacts easily as a dienophile with 2,3-dimethylbutadiene through its 1,6-positions and as a diene with N-phenylmaleimide, dimethyl acetylenedicarboxylate and cyclopentadiene, through its 1,4-positions. 相似文献
14.
E. Gjeçi 《Journal of Radioanalytical and Nuclear Chemistry》1996,213(3):165-174
The use of crown ethers is a simple and rapid method for the separation and determination of strontium in various samples. After sample dissolution oxalate precipitation was carried out to remove K. Chromatographic separation of strontium from most inactive and radioactive interference was done with a crown ether. The chemical recovery was determined gravimetrically. Radiostrontium was then determined by liquid scintillation counting. 相似文献
15.
Formulations of the tin etiopurpurin (SnET2) have been observed to undergo a spectral change on storage in dimethylformamide solution. This results in an alteration in the action spectrum, with enhanced photodynamic activity at lower wavelengths and decreased activity at 660 nm. On the basis of structural considerations, a reduced analog of SnET2 was prepared with an absorbance maximum at 640 nm. Formation of this product, termed SnET2H(2) relieves steric strain inherent in the parent molecule. Nuclear magnetic resonance, spectral and photodynamic data are consistent with the formation of SnET2H(2) during SnET2 storage. Slight modifications in the original synthesis are also reported, resulting in improved yields of intermediate products. 相似文献
16.
R. S. Simon F. Folkmann Ch. Briançon J. Libert J. P. Thibaud R. J. Walen S. Frauendorf 《Zeitschrift für Physik A Hadrons and Nuclei》1980,298(2):121-128
In the actinides bothi 13/2 protons andj 15/2 neutrons are close to the Fermi surface. At rapid rotation these high-j particles will unpair and align their orbital angular momentum along the axis of rotation giving rise tos-bands that cross the ground-state band. Coulomb excitation of the odd nuclei 237 93 Np (established up to the 45/2+ state) and 235 92 U (established up to the 51/2? state) provides specific information about these band crossings: From the saturating alignment of the odd high-j particle in both nuclei at intermediate rotational frequencies we find the aligned angular momentum of thei 13/2 protons-band to be 6.6? while the corresponding value for thej 15/2 neutrons-band is 5.5?. At more rapid rotation above ?ω=0.18 MeV we observe additional alignment in235U. This is ascribed to the interaction of the protons-band. From the gradual onset of the additional alignment we deduce that forZ=92 the protons-band interacts strongly with the ground-state band and from a comparison of the actual amount of alignment with the full value of 6.6? we estimate the crossing to occur around ?gw c p =0.25 MeV. 相似文献
17.
Jean-François Mestre 《Journal of Number Theory》1981,13(2):123-137
Lenstra [Invent. Math.36 (1977), 237–254] has proved that a number field possessing sequences of integers whose differences are units, having a big enough length with respect to the discriminant of the field, is Euclidean. In this paper, we use this result to construct some new Euclidean fields; suitable sequences are obtained by using points of finite order on some elliptic curves. 相似文献
18.
Analytical and Bioanalytical Chemistry 总被引:6,自引:0,他引:6
Mathey F 《Analytical and bioanalytical chemistry》2002,372(1):1
19.
Ângela F. S. S. Mendonça Dina T. R. Formigo Isabel M. S. Lampreia 《Journal of solution chemistry》2002,31(8):653-670
Solubilities of triethylamine in aqueous tetraethylammonium chloride solutions were measured at 20, 25, and 35°C. The molalities in Et4NCl of the aqueous solvents ranged from 0.03 to 1 mol-kg–1. The data were evaluated from density measurements using a vibrating-tube densimeter. At each temperature, least-squares method was used to fit experimental density data points to double polynomial equations of various degrees. Triethylamine molalities of the saturated aqueous phases were estimated by extrapolation from those equations. Experimental data were interpreted in terms of hydrophobic and electrostatic perturbed domains in the hydration shells of the noneleceory and of the cation of the salt, as a function of temperature and salt concentration. The conclusions obtained are consistent with previous volumetric studies. 相似文献
20.
In April 1998 Raimond Castaing left the world of electrons, of ions and others particles, his wife and his family, his numerous
students, for the world of stars.
Raimond Castaing (Fig. 1) had a very strong personality. No one will forget their first meeting with him and all his students
remember how brilliant he was as a teacher. A lot of anecdotes about his famous hot temper are still circulating among his
friends and his former students. But in this paper, we would like to evoke Castaing’s memory through his achievements in Instrumental
Physics, from the time of his doctoral thesis to later developments with his students, which were all centred on the imaging
of the microstructures of materials and their quantitative chemical analysis. 相似文献