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91.
TcO4- in HF solution reacts to form Tc3O9F4- along with some TcO3F. Pure TcO3F is obtained if a mixture of HF/BiF5 is applied. TcO3F dimerizes in the solid state via fluoride bridges, similar to the structures of CrO2F2 and VOF3. TcO3F reacts in HF with AsF5 or SbF5 under formation of TcO2F2+As(Sb)F6-. 相似文献
92.
Scanlon MD Salaj-Kosla U Belochapkine S MacAodha D Leech D Ding Y Magner E 《Langmuir : the ACS journal of surfaces and colloids》2012,28(4):2251-2261
The high surface areas of nanostructured electrodes can provide for significantly enhanced surface loadings of electroactive materials. The fabrication and characterization of nanoporous gold (np-Au) substrates as electrodes for bioelectrochemical applications is described. Robust np-Au electrodes were prepared by sputtering a gold-silver alloy onto a glass support and subsequent dealloying of the silver component. Alloy layers were prepared with either a uniform or nonuniform distribution of silver and, post dealloying, showed clear differences in morphology on characterization with scanning electron microscopy. Redox reactions under kinetic control, in particular measurement of the charge required to strip a gold oxide layer, provided the most accurate measurements of the total electrochemically addressable electrode surface area, A(real). Values of A(real) up to 28 times that of the geometric electrode surface area, A(geo), were obtained. For diffusion-controlled reactions, overlapping diffusion zones between adjacent nanopores established limiting semi-infinite linear diffusion fields where the maximum current density was dependent on A(geo). The importance of measuring the surface area available for the immobilization was determined using the redox protein, cyt c. The area accessible to modification by a biological macromolecule, A(macro), such as cyt c was reduced by up to 40% compared to A(real), demonstrating that the confines of some nanopores were inaccessible to large macromolecules due to steric hindrances. Preliminary studies on the preparation of np-Au electrodes modified with osmium redox polymer hydrogels and Myrothecium verrucaria bilirubin oxidase (MvBOD) as a biocathode were performed; current densities of 500 μA cm(-2) were obtained in unstirred solutions. 相似文献
93.
Reactions of [ReOCl3(PPh3)2] with a potentially tridentate Schiff base derived from (2-formylphenyl)diphenylphosphine and 2-aminophenol, HL1P, (HL1P = Ph2PC6H4-2-HCN(C6H4-2-OH)) result in a rapid decomposition of the Schiff base and the formation of a large number of hitherto non-identified metal-containing species, while from similar reactions with the analogoue phosphine oxide HL1PO, (HL1PO = Ph2P(O)C6H4-2-HCN(C6H4-2-OH)) products of the compositions [ReOCl2(PPh3)(L1PO)] (1) and [Re(NC6H4-2-OH)Cl3(PPh3)2] (2) could be isolated. The structure of 2 is an experimental proof of the preceding, metal-induced cleavage of the C–N double bond. A subsequent reaction of the released 2-aminophenol forms the final phenylimido ligand.Reduction of HL1P with NaBH4 gives the phosphine amine H2L2P (H2L2 = Ph2P(C6H4-2-CH2NH(C6H4-2-OH))) in good yield. Reactions of H2L2P with common oxorhenium(V) complexes result in the formation of the stable rhenium(V) complex [ReOCl2(HL2P)] (3) with a facially coordinated HL2P? ligand. 相似文献
94.
Janine Ackermann Christelle Nijki Noufele Adelheid Hagenbach Ulrich Abram 《无机化学与普通化学杂志》2019,645(1):8-13
[TcI(NO)Cl(H2L1)2]+ cations (H2L1 = 2‐(diphenylphosphanyl)aniline) are formed during reactions of H2L1 with (NBu4)[Tc(NO)Cl4(MeOH)] or (NH4)TcO4/HCl/NH2OH mixtures. Different isomers were isolated depending on the counterions and solvents used. The technetium(I) complexes cis‐NO,Cl,trans‐P,P‐[TcI(NO)Cl(H2L1)2]Cl, trans‐NO,Cl,cis‐P,P‐[TcI(NO)Cl(H2L1)2]2(TcCl6), and trans‐NO,Cl,trans‐P,P‐[TcI(NO)Cl(H2L1)2](PF6) were isolated in crystalline form and studied by spectroscopic methods and X‐ray crystallography. DFT calculations show that there are only minor energy differences between the three isomers and the formation of the individual compounds is most probably strongly influenced by interactions with solvents and counterions. 相似文献
95.
Arnowitt R Dutta B Gurrola A Kamon T Krislock A Toback D 《Physical review letters》2008,100(23):231802
We examine the stau-neutralino coannihilation (CA) mechanism of the early Universe. We use the minimal supergravity (mSUGRA) model and show that from measurements at the CERN Large Hadron Collider one can predict the dark matter relic density with an uncertainty of 6% with 30 fb(-1) of data, which is comparable to the direct measurement by the Wilkinson Microwave Anisotropy Probe. This is done by measuring four mSUGRA parameters m(0), m(1/2), A(0), and tanbeta without requiring direct measurements of the top squark and bottom squark masses. We also provide precision measurements of the gaugino, squark, and lighter stau masses in this CA region without assuming gaugino universality. 相似文献
96.
U. Abram 《无机化学与普通化学杂志》2000,626(3):619-620
[Au(Et2dtc)2][TcNCl4] – Synthesis and Structure [Au(Et2dtc)2][TcNCl4] (Et2dtc– = N,N‐diethyldithiocarbamate) is formed by the reaction of [Au(CO)Cl] with [TcN(Et2dtc)2] in dichloromethane. The solid state structure of the compound is characterized by a large triclinic unit cell (space group, P1, a = 9.422(2), b = 22.594(5), c = 32.153(7) Å, α = 72.64(1), β = 85.19(1), γ = 86.15(1)°, Z = 12) and shows an unusual arrangement due to long‐range contacts between the technetium atoms and sulfur atoms of the [Au(Et2dtc)2]+ units (3.45–3.56 Å) which assemble two anions and one cation to {[TcNCl4][Au(Et2dtc)2] · [TcNCl4]}– moieties. 相似文献
97.
V. M. Strutinsky A. G. Magner V. Yu. Denisov 《Zeitschrift für Physik A Hadrons and Nuclei》1985,322(1):149-156
Density distribution across the nuclear surface is obtained in the approximation of relatively sharp nuclear edge. It is used to determine dynamical parts of the density relevant to density vibration resonances. Results of the simple calculations are in close agreement with detailed microscopic theories. 相似文献
98.
99.
100.
LetX be a standard Gaussian random variable andG an absolutely continuous function. The inequality $$Var G(X) \leqslant E(G'(X))^2 $$ was proved in Nash and later rediscovered in Brascamp and Lieb as a special case of a general inequality and in Chernoff. All the proofs are based on properties of the Gaussian density. By using the characteristic function rather than the density, generalizations with higher order derivatives are obtained. The method also establishes potentially useful connections with Karlin's total positivity. 相似文献