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171.
Dr. Thomas Beth 《Journal of Geometry》1980,15(1):89-92
The dimension of the F-row spaces of the incidence matrices of all affine planes AG(2,n) is determined. The proof presented here gives a unified method for the cases when charF is or is not a divisor of n. 相似文献
172.
Nielsen RD Hustedt EJ Beth AH Robinson BH 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,170(2):277-371
The Bloch equation containing a Zeeman modulation field is solved analytically by treating the Zeeman modulation frequency as a perturbation. The absorption and dispersion signals at both 0 degrees and 90 degrees modulation phase are obtained. The solutions are valid to first order in the modulation frequency, but are otherwise valid for any value of modulation amplitude or microwave amplitude. A first order treatment of modulation frequency is shown to be a valid approximation over a wide range of typical experimental EPR conditions. The solutions derived from the Bloch equation suggest that the effect of over-modulation on first and second harmonic EPR spectra can be formulated as a mathematical filter that smoothes and broadens the under-modulated signal. The only adjustable filter parameter is a width that is equivalent to the applied peak-to-peak modulation amplitude. The true spin-spin and spin-lattice relaxation rates are completely determined from the under-modulated spectrum. The filters derived from the analytic solutions of the Bloch equation in the linear limit of modulation frequency are tested against numerical solutions of the Bloch equation that are valid for any modulation frequency to show their applicability. The filters are further tested using experimental EPR spectra. Experimental under-modulated spectra are mathematically filtered and compared with the experimental over-modulated spectra. The application of modulation filters to STEPR spectra is explored and limitations are discussed. 相似文献
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174.
M Julia BF Flaminio Alexandre S Borges Daryl V Nydam David W Horohov Rolf Hecker Mary Beth Matychak 《Journal of immune based therapies and vaccines》2007,5(1):1-17
Background
Cytosine-phosphate-guanosine oligodeoxynucleotide (CpG-ODN) has been used successfully to induce immune responses against viral and intracellular organisms in mammals. The main objective of this study was to test the effect of CpG-ODN on antigen presenting cells of young foals. 相似文献175.
Gale PA Light ME McNally B Navakhun K Sliwinski KE Smith BD 《Chemical communications (Cambridge, England)》2005,(30):3773-3775
An amidopyrrole with appended imidazole group can bind and co-transport H+/Cl- across vesicle membranes much more effectively than an analogue with an appended pyridyl group. 相似文献
176.
Cameron BR Darkes MC Yee H Olsen M Fricker SP Skerlj RT Bridger GJ Davies NA Wilson MT Rose DJ Zubieta J 《Inorganic chemistry》2003,42(6):1868-1876
The preparation of two Ru(III) polyaminocarboxylate complexes, AMD6245 and AMD6221, and their nitrosyl analogues, AMD6204, AMD6263, and AMD3689, is described. The compounds are characterized by IR, ES-MS, and (13)C and (15)N NMR spectroscopy where appropriate and cyclic voltammetry. The crystal structures for AMD6245, AMD6263, and AMD3689 are presented. AMD6245 (C(10)H(14)N(2)O(9)Ru) crystallized in the P2(1)/c space group with a = 8.4382(2) A, b = 8.8304(2) A, c = 17.6321(4) A, beta = 99.603(o), V = 1295.3(2) A(3), and Z = 4. AMD6263 (C(10)H(14)N(3)O(10)Ru) crystallized in the P2(1)/c space group with a = 9.9043(4) A, b = 13.1144(3) A, c = 12.0914(4) A, beta = 100.191(o), V = 1545.8(5) A(3), and Z = 4. AMD3689 (C(14)H(24.56)N(4)O(13.28)Ru) crystallized in the P1 space group with a = 8.838(2) A, b = 9.452(3) A, c = 13.419(4) A, alpha = 78.413(6)(o), beta = 75.804(6)(o), gamma = 73.562(6)(o), V = 1031.8(5) A(3), and Z = 2. The reaction of AMD6245 and AMD6221 with nitric oxide is investigated using EPR spectroscopy and stopped flow kinetics. Upon reaction with NO, a linear, diamagnetic [RuNO](6) complex is formed. The substitution reaction of AMD6245 with NO proceeds with a second-order rate constant of 2.24 x 10(7) M(-1) s(-1) at 7.3 degrees C (pH = 7.4; 50 mM phosphate buffer). The substitution reaction of AMD6221 with NO proceeds with a second-order rate constant of 3 x 10(5) M(-1) s(-1) at 20 degrees C (pH = 7.4; 50 mM phosphate buffered saline). The NO scavenging ability was assessed using a RAW264 murine macrophage assay by measuring the difference in nitrite produced between untreated control cells and treated cells. At 100 microM AMD6245 has [NO(2-)] = 12.5 microM less than the untreated cells and AMD6221 has [NO(2-)] = 37.6 microM less than the untreated cells. There is an insignificant difference in the amount of nitrite produced between AMD6263 or AMD3689 treated cells and untreated cells. 相似文献
177.
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179.
Mary Beth Stearns 《Journal of magnetism and magnetic materials》1977,5(2):167-171
Values of the electron spin-polarization and their proportionality to bulk moments are easily explained by realizing that they are due to the itinerant d-like electrons. The proportionality of the tunneling current of superconductors and ferromagnets to the three-dimensional density-of-states is seen to occur naturally in the independent particle model. In contrast to tunneling, photoelectrons are dominated by localized electrons; these are also seen to be in agreement with calculated band structure. 相似文献
180.