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21.
Poly(N-vinylcarbazole) layers containing tetra-5-crown-5-gallium phthalocyaninate (R4Pc)Ga(OH) are shown to possess photoelectric and photorefractive sensitivity at a wavelength of 1064 nm. This effect is associated with the formation of supramolecular ensembles of (R4Pc)Ga(OH) molecules with electronic optical absorption in the near-IR range and nonlinear optical properties. For the composite containing 5 wt % (R4Pc)Ga(OH) supramolecular ensembles, the dependence of the quantum efficiency of mobile-charge photogeneration on electric field E 0 is well fit by the Onsager equation expanded to E 0 3 at a quantum yield of electron-hole pairs of φ0 = 0.9 s with an initial separation radius of r 0 = 9.8 Å susceptibility χ(3) equal to 1.85 × 10?10 esu is measured via the well-known method of electric-field-induced second-harmonic generation. Two-beam-coupling gain coefficient Γ is found to be 80 cm?1 at E 0 = 120 V/μm.  相似文献   
22.
Three novel equations were proposed to perform graphical model-free analysis of lanthanide-induced shifts in NMR spectra of axially symmetrical complexes within Bleaney's T(-2) expansion. Application and efficiency of these newly developed approaches were demonstrated on the example of heteroleptic triple-decker crown-phthalocyaninates (Pc)M[(15C5)(4)Pc]M(Pc), where (15C5)--15-crown-5, (Pc(2-))--phthalocyaninato-dianion, M = Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb and Y as diamagnetic reference. By construction of these equations, the proposed analytical techniques are more sensitive to variations of hyperfine coupling terms throughout lanthanide series, in comparison with previously developed approaches, becoming a valuable tool for the investigation of structural and electronic characteristics of lanthanide complexes.  相似文献   
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24.
The solubility of p-n-hexyloxy- and p-n-heptyloxybenzoic acids in nonaqueous solvents of different polarities was determined over the temperature range from ?20 to 60°C. Acid polymorphs were obtained by crystallization from solutions and melts and by the thermal shock method. The temperatures and enthalpies of phase transitions and X-ray characteristics of the new polymorphs were determined.  相似文献   
25.
Complexing properties of lanthanide ions with respect to crown-substituted phthalocyanine are analyzed. Complexes of lanthanides (La, Nd, Sm, Eu, Gd, Tb, Yb, Lu, Y) with tetra-15-crown-5-phthalocyanine are synthesized and their structures are studied by photoelectronic, IR, 1H NMR, and mass spectrometry methods.  相似文献   
26.
The electrochemical model of the system of electroconductive hemosorbent/biological medium was proposed to develop electro-chemically controlled medical detoxification technologies for treat-ment of diseases of certain etiology. It was obtained that the destruc-tion of blood cells as a result of a contact blood with hemosorbents is caused of hemosorbent potential. The potential region of hemosor-bent corresponding of hemocompatibility was determined. Hemo-compatible composite material based on activated carbon covered polypyrrole were synthesized. Certain electrochemical medical tech-nologies for selective removing of endo- and exotoxicants and dam-aged blood cells from biological media of organism were developed.  相似文献   
27.
Russian Journal of General Chemistry - The binding of 68Ga to two organic ligands containing aminodiphosphonic groups (1,7-diamino-4-oxaheptane-1,1,7,7-tetraphosphonic and...  相似文献   
28.
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   
29.
The syntheses of the complex copper salt CuL2 · 2H2O (I) and the erbium nitrate complex Er(NO3)3 · 2HL · 2H2O (II) (HL is 2-[2′-(oxymethyldiphenylphosphinyl)phenyldiazenyl]-4-tert-butylphenol) have been described. Basic vibrational frequencies in the IR spectra of I and II have been interpreted. The crystal structure of I has been determined by X-ray crystallography: the crystals are monoclinic, a = 15.157(3) ?, b = 17.080(2) ?, c = 22.451(9) ?, β = 106.09(3)°, V = 5584(3) ?3, Z = 4, space group C2/c, R = 0.0546 (for 1152 reflections with I > 2σ(I)). The coordination polyhedron of the copper atom (symmetry C 2) can be described as a symmetrically elongated square bipyramid (4+2). The basic square of the Cu polyhedron is formed by the oxygen atom of the substituted phenol and one of the nitrogen atoms of the azo group of each of the two deprotonated ligands L (Cu-N, 1.969(6) ?; Cu-O, 1.899(5) ?). The angles between the opposite O and N atoms are 157.6°, and the other equatorial angles are in the range 90.6°–95.9°. The axial positions are occupied by the anisole O(2) and O(2A) atoms (Cu-O, 2.737(6) ?, the O(2)Cu(1)O(2A) angle, 132.3°). In the crystal of I, complex molecules and water molecules of crystallization are combined by a system of hydrogen bonds. IR spectra show that, in complex II, as distinct from compound I, the HL ligand is coordinated to the erbium atom through the phosphoryl oxygen atom. Original Russian Text ? A.Yu. Tsivadze, L.Kh. Minacheva, I.S. Ivanova, V.E. Baulin, E.N. Pyatova, V.S. Sergienko, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 4, pp. 601–607.  相似文献   
30.
The third-order nonlinear optical properties of the ruthenium (II) complex with tetra-15-crown-5-phthalocyanine and axially coordinated triethylenediamine molecules (R4Pc)Ru(TED)2 were analyzed by means of the z-scanning technique. A solution of (R4Pc)Ru(TED)2 in tetrachloroethane was exposed to nanosecond laser pulses at a wavelength of 1064 nm. It was found that the third-order molecular polarizability of the Ru(II) complex is 4.5 × 10?32 cm4/C (esu). The polarizability per molecule increases by a factor of 3.6 when the single molecule occurs in a supramolecular assembly of (R4Pc)Ru(TED)2 complexes. The photoelectric and photorefractive properties at 1064 nm of polymer composites, determined by the supramolecular assemblies that exhibits optical absorption and photoelectric sensitivity in the near IR region, are reported.  相似文献   
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