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71.
G. S. Tsebrikova V. V. Ragulin V. E. Baulin K. E. German A. O. Malysheva O. E. Klement’eva G. E. Kodina A. A. Larenkov E. A. Lyamtseva N. A. Taratonenkova M. V. Zhukova A. Yu. Tsivadze 《Russian Journal of General Chemistry》2018,88(9):1780-1785
A modified method for the preparation of 2,5-diamino-5,5-diphosphonovaleric acid (DADP5) has been developed in the search for new synthetically available organic ligands to produce 188Re radiopharmaceuticals with an increased accumulation in the bone tissue. Interaction of the obtained acid with 188Re was studied by radio-TLC. An optimal system for separating unbound 188Re and labeled complex in a yield of at least 95% was found. The biological distribution of 188Re-DADP5 was studied based on direct radiometric data. The osteotropicity of 188Re-DADP5 and its increased accumulation in bone fracture sites, which represent oncological pathology models, was detected at a level comparable to known radiopharmaceuticals. 相似文献
72.
R. Klement 《Fresenius' Journal of Analytical Chemistry》1952,136(1):137-139
Ohne Zusammenfassung 相似文献
73.
V. Yamakov A. Milchev G.M. Foo R.B. Pandey D. Stauffer 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,9(4):659-667
A coarse-grained off-lattice bead-spring model is used to reveal the complex dynamics of a polymer chain in a quenched porous
medium in the presence of an external field B. The behavior of the mean square displacement (MSD) of the center chain bead and that of the center of mass of the chain
as a function of time is studied at different values of the barrier concentration C, the field strength B and the chain length N. In a field, important information on the way in which chains move between obstacles and overcome them is gained from the
MSD vs. time analysis in the directions parallel and perpendicular to the flow. Instead of a steady approach to uniform drift-like
motion at low C, for sufficiently strong field B we observe logarithmic oscillations in the effective exponents describing the time dependence of the MSD along and perpendicular to field. A common nature of
this phenomenon with oscillatory behavior, observed earlier for biased diffusion of tracers on random lattices, is suggested.
Received 7 August 1998 相似文献
74.
Effects of a flow field (E) on segregation and flow of polymer chains are studied in two dimensions using a hybrid (discrete‐to‐continuum) simulation. The flow rate (j) of polymer chains is found to increase monotonically with E, a linear response in the low field regime followed by a slow approach to saturation in the high field regime. The effective chain permeability (ϕc = j/E) varies nonmonotonically on increasing the field E, with a maximum (ϕcm) at a characteristic value of the field (in the range 0.2 < E < 2); ϕcm depends on the chain length. Chain aggregates exhibit an anisotropic mass distribution due to the field with a molecular bridging at high fields. The longitudinal component of the radius of gyration (Rgx) exhibits a crossover from a random walk (RW) (Rgx ˜ Lc1/2) at E = 0 to an elongated conformation (Rgx ˜Lc) at E ⪈ 0.2; the transverse component changes from Rgy ˜ Lc1/2 to Rgy ˜ Lc1/3. The width of the radial distribution function (ρ(r)) of the monomers increases while its peak varies nonmonotonically with E and is consistent with the observation of anisotropic mass distribution. 相似文献
75.
The synthesis and characterization of a series of heterocyclic liquid crystal, 4-{[(thiophen-2-yl)methylidene]amino}phenyl 4-alkoxybenzoates possessing even number of carbon atoms at the alkoxy chain (CnH2n+1O-, n = 6, 8, 10, 12, 14, 16, 18) are reported. The molecular structures of title compounds were elucidated using Fourier-transform infrared spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopic techniques along with mass spectrometric analysis. The phase behavior of these compounds was characterized and studied by differential scanning calorimetry and polarizing optical microscopy. All members exhibited enantiotropic nematic phase except for the highest member (n = 18) which is a non-mesogen. Influence of alkoxy chain length on the transition temperatures of crystal-to-nematic (melting point) and nematic-to-isotropic (clearing point) was studied. Nematic phase range was found to increase from n = 6 to n = 10, then it started to descend from n = 12 to n = 16 and finally the nematic phase disappeared when n changed to 18. 相似文献
76.
77.
Xinyi Ye Adhitya Mangala Putra Moeljadi Kek Foo Chin Prof. Dr. Hajime Hirao Dr. Lili Zong Prof. Dr. Choon‐Hong Tan 《Angewandte Chemie (International ed. in English)》2016,55(25):7101-7105
The first enantioselective tungstate‐catalyzed oxidation reaction is presented. High enantioselectivities were achieved for a variety of drug‐like phenyl and heterocyclic sulfides under mild conditions with H2O2, a cheap and environmentally friendly oxidant. Synthetic utility was demonstrated through the preparation of (S)‐Lansoprazole, a commercial proton‐pump inhibitor. The active ion‐pair catalyst was identified to be bisguanidinium diphosphatobisperoxotungstate using Raman spectroscopy and computational studies. 相似文献
78.
Lectin affinity electrophoresis of alkaline phosphatase for the differentiation of bone and hepatobiliary disease 总被引:1,自引:0,他引:1
An affinity electrophoresis procedure is described for the separation and quantification of the bone- and liver-derived fractions of alkaline phosphatase in plasma. Separation is carried out on cellulose acetate membrane pre-soaked with buffer containing wheat germ lectin. The electrophoretic mobility of the bone enzyme is preferentially retarded by the lectin and this fraction is well separated from the liver fraction. After separation, enzyme activity is demonstrated by staining using an indigogenic alkaline phosphatase substrate incorporated in agar gel, and the stained fractions quantified by densitometry. The procedure has low imprecision, good linearity, and the activities of the bone and liver fractions correlate well with values obtained using nonelectrophoretic quantification methods. The procedure is especially suitable for use in the diagnostic laboratory. 相似文献
79.
O. G. Mishchenko S. V. Klement’eva S. V. Maslennikov A. N. Artemov I. V. Spirina 《Russian Journal of General Chemistry》2006,76(12):1907-1910
Photolytic decomposition of styrene, stilbene, and 1,4-diphenylbuta-1,3-diene tricarbonyl chromium complexes in solution results in elimination of the carbonyl ligands and formation of binuclear alkenylarene chromium complexes. The quantum yields and activation and kinetic parameters of these processes were determined, and a scheme was proposed to rationalize photoinitiated transformations of the organochromium compounds under study. 相似文献
80.