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Using wide-band (0.5-6.5 eV) spectroscopic ellipsometry we study ultrathin [Bi(0.6-2.5 nm)-FeNi(0.8,1.2 nm)]N multilayer films grown by rf sputtering deposition, where the FeNi layer has a nanoisland structure and its morphology and magnetic properties change with decreasing the nominal layer thickness. From the multilayer model simulations of the ellipsometric angles, Psi(omega) and Delta(omega), the complex (pseudo)dielectric function spectra of the Bi layer were extracted. The obtained results demonstrate that the Bi layer can possess the surface metallic conductivity, which is strongly affected by the morphology and magnetic properties of the nanoisland FeNi layer in the GMR-type Bi-FeNi multilayer structures., 6 pages, 4 figures

On the basis of the 1,2,3,4-tetrahydrofluorenyl ligand, a simple approach was developed to new effective rhodium catalysts for the construction of C-C and C-N bonds. The halide compounds [(η5 -tetrahydrofluorenyl)RhX2 ]2 (2 a: X=Br; 2 b: X=I) were synthesized by treatment of the bis(ethylene) derivative (η5 -tetrahydrofluorenyl)Rh(C2 H4 )2 (1 a) with halogens. An analogous reaction of the cyclooctadiene complex (η5 -tetrahydrofluorenyl)Rh(cod) (1 b) with I2 is complicated by the side formation of [(cod)RhI]2 . The reaction of 2 b with 2,2'-bipyridyl leads to cation [(η5 -tetrahydrofluorenyl)Rh(2,2'-bipyridyl)I]+ (3). The halide abstraction from 2 a,b with thallium or silver salts allowed us to prepare sandwich compounds with incoming cyclopentadienyl, dicarbollide and mesityleneligands [(η5 -tetrahydrofluorenyl)RhCp]+ (4), (η5 -tetrahydrofluorenyl)Rh(η-7,8-C2 B9 H11 ) (5), and [(η5 -tetrahydrofluorenyl)Rh(η-mesitylene)]2+ (6). The structures of 1 b, 2 b ⋅ 2I2 , 3PF6 , 4TlI4 , 5, and [(cod)RhI]2 were determined by X-ray diffraction. Compounds 2 a,b efficiently catalyze the oxidative coupling of benzoic acids with alkynes to selectively give isocoumarins or naphthalenes, depending on the reaction temperature. Moreover, they showed moderate catalytic activity in other annulations of alkynes with aromatic compounds (such as benzamide, acetanilide, etc.) which proceed through CH activation. Compound 2 b also effectively catalyzes the reductive amination of aldehydes and ketones in the presence of carbon monoxide and water via water-gas shift reaction, giving amines in high yields (67-99 %).

Heterocyclization of ethyl 2-acetyl(aroyl)-5-methylthieno[2,3-b]thiophene-3-acetates with hydrazine hydrate has been studied. A dependence of the reaction direaction on the nature of the substituent in the acyl fragment was established. The heterocyclization of ethyl 2-aroyl-5-methylthieno[2,3-b]thiophene-3-acetates leads to derivatives of thieno[3',2':4,5]thieno[2,3-d][1,2]diazepin-5-ones. The cyclization of ethyl 2-acetyl-5-methylthieno[2,3-b]thiophene-3-acetate with hydrazine hydrate forms a six-membered ring, viz. 2-aminothieno[3',2':4,5]thieno[2,3-c]pyridin-5(6H)-one.

A new synthetic approach to fused azepines was demonstrated on an example of the synthesis of 2-methyl-2,3,4,5-tetrahydro-1H-[1]benzothieno[2,3-c]azepine. The key stage of the synthesis is the formation of the azepine ring under the Eschweiler–Clark reaction conditions. The Gibbs energy of activation for the inversion of the azepine ring was determined by dynamic 1H NMR spectroscopy. Molecular modeling of the structure and estimation of the 1H and 13C NMR chemical shifts were performed for 2-methyl-2,3,4,5-tetrahydro-1H-[1]-benzothieno[2,3-c]azepine. The magnetic shielding tensors were calculated by the standard GIAO method using the B3LYP/6-31G(d,p)-optimized molecular geometry parameters. The solvent effect was taken into account in the PCM approximation. The calculated 1H and 13C NMR chemical shifts of 2-methyl-2,3,4,5-tetrahydro-1H-[1]-benzothieno[2,3-c]azepine are in good agreement with the experimental values observed in the spectra of its DMSO-d6 solution.

The η6-fluorene cyclopentadienyl complexes [(η5-C5R5)M(η6-fluorene)](SbF6)2 (1: M = Co, R = Me; 2a: M = Rh, R = H; 2b: M = Ir, R = H) were synthesized by the iodide abstraction from [(η5-C5R5)MI2]n...

We have tested the conduction band electrons of lanthanum hexaboride that is among the most effective electron-beam sources with one of the highest brightness of thermionic emission. We performed infrared spectroscopic, DC (direct current) resistivity and Hall-effect studies of LaB6 single crystals with various 10B and 11B isotope contents. We find that only a small amount of conduction electrons behave as Drude-type charge carriers while about 70% of the electrons are involved in collective oscillations of electron density coupled to vibrations of both the Jahn-Teller unstable rigid boron cage and rattling modes of La-ions loosely bound to the lattice. We suggest that exactly these non-equilibrium conduction electrons determine the extraordinary low work function of thermoemission in LaB6.

Cyclopentadienyl cobalt complexes have been known since 1953. In the recent years, they have attracted attention of chemists due to their application in C–H activation reactions. The review covers the synthesis of cyclopentadienyl cobalt(III) complexes with diverse auxiliary ligands (such as carbonyl, halides, solvents, arenes, amines, phosphines etc.) as well as their catalytic activity. The influence of auxiliary ligands on the catalytic activity is discussed.

A number of new 1-substituted 5,10-dihydro[1,2]diazepino[4,5-b]indole-4(3H)-ones were synthesized, and their structural modification was performed to obtain previously unknown amino and fused triazolo derivatives.

The authors show several experimental indications of superconductivity with the onset above 40 K in multiphase strontium ruthenate doped by rhenium and selenium.

Using methods of pulsed laser ablation from a silicon target in helium (He)-nitrogen (N2) gas mixtures maintained at reduced pressures (0.5&ndash, 5 Torr), we fabricated substrate-supported silicon (Si) nanocrystal-based films exhibiting a strong photoluminescence (PL) emission, which depended on the He/N2 ratio. We show that, in the case of ablation in pure He gas, Si nanocrystals exhibit PL bands centered in the &ldquo, red - near infrared&rdquo, (maximum at 760 nm) and &ldquo, green&rdquo, (centered at 550 nm) spectral regions, which can be attributed to quantum-confined excitonic states in small Si nanocrystals and to local electronic states in amorphous silicon suboxide (a-SiOx) coating, respectively, while the addition of N2 leads to the generation of an intense &ldquo, green-yellow&rdquo, PL band centered at 580 nm. The origin of the latter band is attributed to a radiative recombination in amorphous oxynitride (a-SiNxOy) coating of Si nanocrystals. PL transients of Si nanocrystals with SiOx and a-SiNxOy coatings demonstrate nonexponential decays in the micro- and submicrosecond time scales with rates depending on nitrogen content in the mixture. After milling by ultrasound and dispersing in water, Si nanocrystals can be used as efficient non-toxic markers for bioimaging, while the observed spectral tailoring effect makes possible an adjustment of the PL emission of such markers to a concrete bioimaging task.

A new strategy has been proposed for the synthesis of 5H-[1]benzofuro[2,3-d][1,2]diazepines containing two aryl substituents in the diazepine fragment. The key stage of the synthesis is intramolecular cyclization of the corresponding hydrazides under the Bischler–Napieralski reaction conditions.

Elastically strained metastable Ge1–xSn x layers with molar fractions of tin of up to 0.15 are grown on Si (001) substrates. To analyze the optical properties of the samples, photoluminescence (PL) spectra are measured at room temperature and IR transmission spectra are measured at the liquid helium temperature. The room temperature direct intrinsic absorption edge at 0.71–0.72 eV is visible in the spectra of the studied structures with tin contents of 12–13%.

By measuring room temperature infrared (40–35000 cm–1) reflectivity of metallic LuB12 single crystals with different isotopic compositions (natB, 10B, 11B), we find that to model the spectrum we had to introduce, additionally to Drude free-carrier component, a broad excitation with unusually large dielectric contribution (Δe = 8000 ± 4000), which is characterized by a non-Lorentzian lineshape. It is suggested that the origin of the excitation is connected with cooperative dynamics of Jahn–Teller active B12 molecules producing quasilocal vibrations (rattling modes) of caged lutetium ions. The coupling of the Lu3+ rattling motions with the charge carriers of conduction band is proposed to be the reason of strongly damped character of the excitation.

To understand mechanisms of high thermionic emission of LaB 6 we use infrared spectroscopy, DC resistivity and Hall-effect techniques to study conduction electrons state in LaB6 single crystals with different contents of 10B and 11B isotopes. We find that up to 70% of conduction electrons are strongly non-equilibrium due to involvement in the collective oscillations of electron density coupled to vibrations of Jahn-Teller unstable boron cage and rattling modes of La-ions. We claim that these non-equilibrium electrons determine the extraordinary low work function of thermoemission in LaB 6 .

Reaction of dimethylamine adduct of 1-methyl-3-borolene with [(C2H4)2RhCl]2 gives the triple-decker complex (η-C4H4BMe)Rh(μ-η:η-C4H4BMe)Rh(η-C4H4BMe) (1a) in 62% yield and trace amount (

The arene iridium complexes [(η5-C5R5)M(η6-PhX)](SbF6)2 (1a: R = H, X = CH=CHPh; 1b: R = Me, X = CH=CHPh; 2: R = Me, X = C≡CPh; 3: R = Me, X = 4-Me-1H-isochromen-1-one) were synthesized by the reactions of the halides [CpIrI2]n or [Cp*IrCl2]2 with trans-stilbene, tolan and 3-phenyl-4-methyl-1H-isochromen-1-one in the presence of AgSbF6. They have proved to be stable towards the arene replacement with nucleophiles (such as acetonitrile, water and KI). The structures of 1b(SbF6)2 and 3(SbF6)2 were determined by X-ray diffraction. The experimental and DFT calculation data showed that the coordination of trans-stilbene and 3-phenyl-4-methyl-1H-isochromen-1-one with the Cp*Ir-moiety leads to the fluorescence quenching due to the intramolecular charge transfer from the ligand to iridium.

The reaction of the bromide complexes [CpCo(μ-1,3-C3B2Me5)MBr2]2 [M = Rh (1), Ir (2); Cp = cyclopentadienyl] with AgBF4 in acetonitrile affords the tris(acetonitrile) μ-diborolyl triple-decker complexes [CpCo(μ-1,3-C3B2Me5)M(MeCN)3]2+ [Rh (3), Ir (4)]. The labile nitromethane solvates [CpCo(μ-1,3-C3B2Me5)M(MeNO2)3]2+, generated in a similar way, react with benzene and its methylated derivatives to give the arene triple-decker complexes [CpCo(μ-1,3-C3B2Me5)M(arene)]2+ [M = Rh (5), Ir (6); arene = C6H6 (a), 1,2,4,5-Me4C6H2 (b), C6Me6 (c)]. The structures of 5b(BF4)2, 5c(BF4)2, 6b(BF4)2 and 6c(BF4)2 were determined by X-ray diffraction. The electron-transfer ability of the arene complexes was ascertained by electrochemical techniques. In general, they are able to undergo two separate one-electron reductions reversibly. DFT calculations revealed structural changes caused by redox processes and satisfactorily predicted the redox potentials. The second reduction is accompanied by a η6 η4 hapticity change of the arene ligand. Energy decomposition analysis revealed that the Rh–benzene bond in cation 5a is weaker than in cyclopentadienyl analogues [(C5R5)Rh(C6H6)]2+; however, 5a proved to be the least reactive in benzene replacement with acetonitrile and mesitylene.

Non-symmetrically substituted ruthenocenes CpRuCp´ (Cp´ = C5H4CHO (1a), C5H4COMe (1b), C5H4SiMe3 (1c), 1,3-C5H3(SiMe3)2 (1d), and Cp* (1e)) were synthesized in high yields by the reaction of [CpRu(MeCN)3]+ with cyclopentadienide anions. The structures of complexes 1a,b,d were determined by X-ray diffraction analysis. According to the energy partition analysis data, donor substituents strengthen the interaction between the [RuCp]+ and Cp´– fragments, whereas acceptor substituents weaken the interaction. This bond is predominantly electrostatic (56—59%). Based on the calculated electrostatic potentials at the ruthe-nium nucleus, it is shown that the donor ability of the substituents decreases in the following order: NMe2 > NH2 > OMe > Me ≈ OH > Rc > Fc ≈ Allyl ≈ H > SiMe3 > CH=CH2 ≈ Ph > PH2 > > SH ≈ F > SiH3 ≈ C≡CH > Cl > Br ≈ I ≈ COOMe > COOH > COMe > CF3 > CHO > CN > NO2.

The reaction of the thallium derivative [CpCo(μ-C3B2Me5)]Tl with [Rh(C2H4)2Cl]2 affords the μ-diborolyl bis(ethylene) triple-decker complex CpCo(μ-C3B2Me5)Rh(C2H4)2 (4). Structure of 4 was determined by X-ray diffraction. According to DFT calculations, the ethylene dissociation energies for the triple-decker complexes CpCo(μ-C3B2R5)Rh(C2H4)2 (R = H, Me) are ca. 6 kcal mol−1 lower than for cyclopentadienyl analogs (C5R5)Rh(C2H4)2. Energy decomposition analysis revealed that the bonding of anions [CpCo(C3B2R5)]− with [Rh(C2H4)2]+ is also weaker than that of [C5R5]−; the attractive interactions in both cases are 60–63% electrostatic and 37–40% covalent. The electrostatic potentials at the Rh nuclei suggest that the donor ability of the anions increases in the following order: Cp

Cationic triple-decker complexes with a bridging diborolyl ligand, [CpCo(μ-1,3-C3B2Me5)M(ring)]+ (M(ring) = CoCp (2a), CoCp* (2b), RhCp (3a), RhCp* (3b), IrCp (4a), IrCp* (4b), Ru(C6H6) (5a), Ru(p-MeC6H4Pri) (5b), Ru(C6Me6) (5c), Ru(η6-cycloheptatriene) (6)), were synthesized by reaction of CpCo(μ-1,3-C3B2Me5)Tl with [M(ring)Hal2]2. The structures of 2aBPh4, 2bPF6, 4aPF6, 5aOTf, and 5cPF6 were determined by X-ray diffraction. The electron-transfer ability of the complexes has been ascertained by electrochemical and spectroelectrochemical techniques. In general, they are able to shuttle reversibly in the sequence 2+/+/0/–, plausibly affording completely delocalized mixed-valence derivatives. DFT calculations revealed structural changes accompanying redox processes and satisfactorily predicted the potentials for the first reduction and first oxidation.

The dimeric triple-decker type halides [CpCo(μ-1,3-C3B2Me5)MX2]2 (M = Rh, X = Cl, 1; M = Ir, X = Cl, 2; M = Rh, X = Br, 3; M = Ir, X = Br, 4) react with Me2SO and PPh3 giving adducts CpCo(μ-1,3-C3B2Me5)M(L)X2 (5–12). The Me2SO ligand is S-bonded to the metal atom in the solid state, while in acetone it is O-bonded. Structures of 5–12 were confirmed by X-ray diffraction.

The reaction of CpCo(1,3-C3B2Me5H) (1) with CpTl affords the thallium derivative CpCo(1,3-C3B2Me5)Tl (2). The structures of 1 and 2 were determined by X-ray diffraction at 100 K. An “extra” hydrogen atom in 1 occupies a C–H···B bridging position. According to DFT calculations, 1 exists as a mixture of two enantiomers with an enantiomerization barrier of only 0.5 kcal mol–1. The transition state has Cs symmetry with an endo-CH hydrogen atom. The isomeric iso-1with the Co–H···B bridge is less stable than 1 by 10 kcal mol–1.The formation of 1 and iso-1 from C3B2Me5H and CpCo(C2H4)2 have almost equal activation energies. The isomerization of iso-1 to 1 was shown to proceed as a two-step hydrogen transfer. The bonding of the “extra” hydrogen atom in the related CHB-bridged carborane nido-2,3,5-C3B3R5H2 and metallacarboranes M(C5R5)(C3B2R′5H) (R, R′ = H, Me; M = Co, Rh, Ir) as well as their hydridic isomers MH(C5R5)(C3B2R′5) was compared. According to energy decomposition analysis, the bonding of the parent anion [CpCo(1,3-C3B2H5)]– with metal cations becomes stronger in the following order: K+ < Na+ < Tl+ < Li+ < [RuCp]+. The attractive interactions between the [CpCo(1,3-C3B2H5)]– and Tl+ fragments are 68 % electrostatic and 32 % covalent.

The 86-electron dicationic octahedral rhodium clusters containing Cp (Cp = C5H5) ligands and either an interstitial carbon atom, [Rh6Cp6(μ6-C)]2+ ([1]2+), or two carbonyl groups, [Rh6Cp6(μ3-CO)2]2+ ([2]2+), were synthesized in low yields by reactions of Rh3Cp3(μ-CO)3 with RhCp(C2H4)2 or [RuCp∗(MeCN)3]+ (Cp∗ = C5Me5), respectively. The structures of [1]2+ and [2]2+ were determined by X-ray diffraction. Their electrochemical behavior proved that they possess a rather extended electron transfer activity. In accordance with DFT calculations, the nearly octahedral structure of [1]2+ and [2]2+ is retained both upon oxidation (2+/3+) and the first reduction (2+/+); however, the second reduction (+/0) results in the breaking of one (for [1]0) or two (for [2]0) Rh–Rh bonds. In the case of the related Dahl’s nickel cluster Ni6Cp6 the nearly octahedral structure is retained upon all redox steps (3+/2+/+/0/−/2−).

Cationic triple-decker complexes [CpCo(1,3-C3B2Me5)Ru(arene)]PF6 (arene is benzene (2a), p-cymene (2b)) with a bridging diborolyl ligand were synthesized by the reaction of the sand-wich anion [CpCo(1,3-C3B2Me5)]− (1) with [(arene)RuCl2]2. The structure of [2b]PF6 was confirmed by X-ray diffraction analysis.

Triple-decker complexes with a bridging diborolyl ligand CpCo(μ-1,3-C3B2Me5)M(ring) (M(ring) = RuCp, 4; RuCp*, 5; Co(C4Me4), 6) were synthesized by electrophilic stacking of the sandwich anion [CpCo(1,3-C3B2Me5)]− with the [(ring)M(MeCN)3]+ cations. Structures of 4−6 were confirmed by X-ray diffraction. The electrochemical and spectroelectrochemical behavior of the complexes prepared was studied. DFT calculations of the redox potentials were also performed. Similar bonding properties of anions [CpCo(1,3-C3B2R5)]− and [C5R5]− (R = H, Me) toward [M(ring)]+ cations were established both experimentally (synthesis, electrochemistry, and X-ray diffraction) and theoretically (energy decomposition and Mulliken population analysis).

The cationic triple-decker complexes [CpCo(1,3-C3B2Me5)M(C5R5)]+ (M = Rh (2), Ir (3), R = H (a), Me (b)) with the bridging diborolyl ligand were synthesized by the reaction of the sandwich anion [CpCo(1,3-C3B2Me5)]- (1) with the halide complexes [CpMI2]2 or [Cp*MCl2]2 (Cp* = C5Me5). The structures of [2b]PF6 and [3b]PF6 were established by X-ray diffraction. The nature of the metal—diborolyl bond in these complexes was analyzed using the energy decomposition scheme.

The B-phenylborole complex CpRh(η 5 -C 4 H 4 BPh) ( 1 ) reacts with [ML] + fragments to give the arene-type cationic complexes [CpRh(μ-η 5 :η 6 -C 4 H 4 BPh)ML] + (ML = RuCp ∗ ( 3 ), Co(C 4 Me 4 ) ( 4 ), Rh(cod) ( 5 ), and Ir(cod) ( 6 )). Cation 4 undergoes a reversible rearrangement into the triple-decker complex [CpRh(μ-η 5 :η 5 -C 4 H 4 BPh)Co(C 4 Me 4 )] + ( 7 ) under visible light irradiation in CH 2 Cl 2 solution. DFT calculations revealed greater stability of arene-type complexes over triple-decker isomers. The structure of [ 3 ]BF 4 was determined by X-ray diffraction.

The review summarizes the results of the recent author’s research on the synthesis of triple-decker complexes with bridging borole ligand. Electrophilic stacking of sandwich compounds with [(ring)M] n+ (n = 1, (ring)M = (C5R5)Ru, (C4Me4)Co; n = 2, (ring)M = Cp*Co, Cp*Rh, etc.) cationic fragments were used as a general method of synthesis of the complexes. The influence of the substituent at the boron atom on the course of stacking reactions is discussed. The spectral, structural, and electrochemical properties of the complexes synthesized are also considered.

The (borole)iodide complex [(η 5 -C 4 H 4 BPh)RhI] 4 reacts with the carborane anion [Carb′] − (Carb′ = 9-SMe 2 -7,8-C 2 B 9 H 10 ) giving (Carb′)Rh(η 5 -C 4 H 4 BPh) ( 2 ). Reactions of 2 with dicationic fragments [LM] 2+ afford the μ-borole triple-decker complexes [(Carb′)Rh(μ-η 5 :η 5 -C 4 H 4 BPh)ML] 2+ [LM = Cp ∗ Ir ( 4 ), (Carb′)Rh ( 7 )] or the arene-type complexes [(Carb′)Rh(μ-η 5 :η 6 -C 4 H 4 BPh)ML] 2+ [LM = Cp ∗ Rh ( 3 ), (Carb′)Ir ( 8 )]. The structure of 4 (BF 4 ) 2 was determined by X-ray diffraction.

Triple-decker complexes with a bridging borole ligand (C4H4BPh)Rh(μ-C4H4BPh)ML (ML = RuCp, 2a; RuCp∗, 2b; FeCp∗, 3; Co(C4Me4), 4; Ir(cod), 5) were synthesized by stacking reactions of [Rh(C4H4BPh)2]− (1) with cationic [ML]+ fragments. The structures of 2a,b and (C4H4BPh)Rh(μ-C4H4BPh)Rh(C4H4BPh) (6) were determined by X-ray diffraction.

Within the framework of PM3 molecular orbital approximation the thermodynamic function characteristics for the formation and geometrical structure of monomers, dimers, trimers, and tetramers of nondissociated n-carboxylic acids C(n)H(2n+1)COOH with n = 5-15 are calculated. It is shown that spontaneous aggregation of homologous fatty acids for the homologues with carbon atoms numbers n > or = 13 at the air/water interface can take place, leading to the formation of infinite plane rectangular clusters, whereas for the homologues with n < 11 spontaneous decomposition of large aggregates is energetically preferable. At the same time, the formation of trimers is more probable for the lower homologues (8 < n < 13). These results agree well both with the experimental data reported by various authors and with thermodynamic models developed earlier for soluble and insoluble monolayers. The slopes of the regressions calculated for the dependencies of the thermodynamic parameters on the alkyl chain length for all the clusters considered are all equal to each other. This fact indicates that the contributions of the CH2 groups to the thermodynamic characteristics of alcohols and acids are the same, and the differences in the formation of clusters by these substances should be attributed only to the differences in the structure and interactions of relevant functional groups. Therefore, it enables one to describe both acids and alcohols within the framework of the developed method, and it makes it possible to extend the proposed approach onto other classes of amphiphilic compounds.

New dinuclear ruthenium manganese complexes of general composition (bpy)2Ru(L)MnClx(H2O)2 (L is 1,10-phenanthroline-5,6-dione, 3,3′-dicarboxy-2,2′-bipyridyl, or bis(pyrazolyl); x = 2 or 4) were synthesized by the reaction of (bpy)2Ru(L) with MnCl2 · 4H2O. These compounds and the starting mononuclear ruthenium complexes were studied by spectrophotometric and electrochemical methods in MeCN. The position of the charge-transfer band RuII → L in the spectra depends on the donor-acceptor characteristics of the ligand L. For the dinuclear complex under study, the formal potentials of reversible one-electron oxidation of RuII are in the range of 0.9–1.2 V (vs. the standard hydrogen electrode), whereas oxidation of MnII occurs at more positive (by 0.1–0.2 V) potentials.

Background . Escherichia coli strains that cause cystitis posses virulence properties that facilitate their colonisation and persistence in the bladder. In Iran, despite the high number of the urinary tract infections, very few studies has been done to determine the role of these virulence properties in the pathogenesis of E. coli cyctitis. Patients and methods . Eighty-seven strains of E. coli , isolated from young adults with cystitis in Shiraz, Iran, were examined for the expression of type 1 and P-fimbriae, mannose resistant haemagglutination, haemolysin production, aerobactin-mediated iron uptake, O:K serotypes, biochemical phenotypes (BPTs) and their antibiotic susceptibility patterns. Results . Seventy-six percent of the strains expressed multiple virulence properties. There was a significant correlation between the presence of aerobactin and the expression of type 1 fimbriae. All P-fimbriated strains produced aerobactin with 50% of them also coexpressing haemolysin. Of the 29 different O:K serotypes identified, 42% belonged to serotypes not commonly found among European serotypes associated with UTI. Strains of O groups 4 and 6 expressed more virulence factors than the others. A high resistance against ampicillin, trimethoprim and cotrimoxasol was observed among the isolates with 53% of the isolates showing multiresistance to these three antibiotics. Certain BPTs were also found among O:K serotypes with some containing strains of the same virulence profile. Conclusion . We conclude that certain colonal groups of E. coli are commonly associated with cystitis in young adults in Iran with strains possessing a combination of aerobactin and type 1 fimbriae being the dominant ones and belonging to serotypes not commonly found in Europe. We also conclude that the multiple antibiotic resistant E. coli strains causing cyctitis are highly prevalent in this part of the country.

The goal of a demonstration fusion reactor ceramic helium cooled (CHC) blanket test module (BTM) is to demonstrate a breeding capability that would lead to tritium self-sufficiency in the ITER reactor and to heat with parameters suitable for electricity generation. For validation of the CHC BTM breeding zones feasibility we have developed and fabricated two models for testing in an IVV-2M reactor. Structural material of the models is ferritic-martensitic steel. The breeder material is lithium orthosilicate in pebble-beds and pellet forms. The multiplier material is beryllium in pebble-beds and porosity forms. Cooling is provided by helium at 10 MPa. The tritium produced in the breeder material is purged by a flow of helium + 0.1% of hydrogen at 0.1–0.2 MPa. Designs of models are described and results of neutronic and thermo-hydraulic calculations are presented.

The benzene complex [(η6-C6H6)OsCl2]2 (1) was obtained in 97% yield from thermal or microwave-assisted reaction of Na2OsCl6 with 1,3-cyclohexadiene in aqueous ethanol. Further reaction of 1 with TlCp gives [CpOs(η6-C6H6)]PF6 in 75% yield. Treatment of [CpM(η6-C6H6)]PF6 (M = Ru and Os) with NaBH4 in wet THF affords the cyclohexadienyl complexes CpM(η5-C6H7) in almost quantitative yields. The structure of [CpOs(η6-C6H6)]BArF (BArF = [B((3,5-(CF3)2)C6H3)4]) was confirmed by X-ray diffraction.

A mathematical model is suggested for the high-frequency heating of a live tissue containing a small malignant tumor. The tumor is preliminarily filled with a polymer to prevent heat extraction by flowing blood. The polymer must contain a dispersed ferromagnetic to ensure inductive heating. The unsteady-state temperature profiles obtained by numerically solving the biothermal equation are used to estimate the degree of thermal destruction of the tumor cells.

Triple-decker complexes CpCo(μ-1,3-C3B2Me5)M(η-7,8-C2B9H11) (M = Rh (3), Ir (4)) were synthesized by the reaction of [CpCo(μ-1,3-C3B2Me5)MBr2]2 (M = Rh, Ir) with Tl[TlC2B9H11]. The structure of 3 was established by X-ray diffraction analysis.

Dicationic triple-decker complexes [CpCo(μ-1,3-C3B2Me5)M(C6H6)]2+ (M = Rh (3), Ir (4)) were synthesized by the reaction of [CpCo(μ-C3B2Me5)MBr2]2 (M = Rh, Ir) with benzene in the presence of AgBF4. The structure of 3(BF4)2 was determined by X-ray diffraction analysis.

The cationic complex [Cp*Ru(C5Me4CH2)]+ reacts with Et3N primarily giving the ammonium salt [Cp*Ru(C5Me4CH2NEt3)]+. The prolonged standing of the reaction mixture results in the formation of the ether Cp*Ru(C5Me4CH2OCH2C5Me4)RuCp*. The reaction of [Cp*Ru(C5Me4CH2)]+ with PhNEt2 leads to the electrophilic aromatic substitution product [Cp*Ru(C5Me4CH2C6H4NHEt2)]+.

To analyze the activation of ITER blanket structural components, the authors have prepared the AUCDAS code that calculates changes in nuclide concentrations and radioactivity characteristics during neutron irradiation and during cooling. UCDAS takes into account all neutron reactions and decay types, the prepared library of constants contains nuclear data of nuclides from hydrogen to californium. A comparative analysis of the results as obtained using UCDAS code and the widely known FISPACT code is given. The analysis of decay heat, gas generation and activity of ITER blanket first wall's structural components was carried out. The beryllium coating, copper alloy and stainless steel were analysed. Calculations were performed for the first plasma burning pulse, 6 months and 1 year of operation in accordance with the ITER scenario. The materials recommended by ITER central team and their Russian analogs were considered: TGR and B1 (beryllium coating), GlidCop AL-25 Ds and Br-MKX (copper alloy), 316LN-IG and 12Cr18Ni10Ti (stainless steel). It has been demonstrated that there is a difference in all of the considered characteristics between the above materials. It is caused by impurities which are present in the materials. The report also considers the accumulation of gases (H, D, T, He3,He4) in the above materials. Besides, the change in the activity of irradiated materials during the cooling of up to 107 years was calculated.

Triple-decker complexes with a bridging diborolyl ligand CpCo(μ-1,3-C3B2Me5)M(CO)3 (M = Mn, 2; Re, 3), CpCo(μ-1,3-C3B2Me5)Ru(CO)2Cl (4) and CpCo(μ-1,3-C3B2Me5)Ru(CO)(μ-CO)2Ru(CO)Cp (5) were synthesized by reaction of the sandwich anion [CpCo(1,3-C3B2Me5)]– (1) with [(naphthalene)Mn(CO)3]+, [Re(CO)3(THF)2Br]2, or [Ru(CO)3Cl2]2. Structures of 4 and 5 were determined by X-ray diffraction. The spectroelectrochemical behaviour of compounds 2 and 3 was studied. IR-spectroscopical and computational data suggest that anion 1 is significantly stronger donor than Cp− but slightly weaker than Cp*–.

A number of earlier unknown tri- and tetranuclear organometallic clusters of group VIII transition metals was synthesized by the addition of coordinatively unsaturated species to a single metal-metal bond. A number of novel heteronuclear clusters, CpCp 2 ′ Rhm2(μ−CO)3(μ3−CO), (Cp′=Cp, Cp*; M2=Ru2, Fe2; RuFe); Cp2Cp 2 * Rh2M2(μ3−CO)3 (M = Ru, Fe); , Cp3Cp*Rh3M(μ3−CO)2(μ3−d) (M = Ru, Fe); Cp2Cp 2 *> Rh2Co2(μ3−CO)2,etc., was obtained.

Protective coatings based on metallic aluminum are developed that can be used to improve the resistance of the refractory lining for extra-furnace steelmaking facilities. By sintering a slurry sprayed on the refractory surface, a heat-resistant gas-impermeable coating containing α-corundum is formed.

Stacking reactions of the dicationic fragments [LM]2+ (LM = (η-C6H6)Ru, (η-C6H3Me3)Ru, or (η-C5Me5)Rh) with the complex (η-C5H5)Co(η-C4H4BCy) (Cy = cyclo-C6H11) afforded new dicationic 30-electron triple-decker complexes [(η-C5H5)Co(μ-η:η-C4H4BCy)ML](BF4)2 containing a cyclohexyl-substituted borole ligand in the central position.

The behaviour of the three-membered metallacycle Cp 3 Rh 3 (μ-CO) 3 is similar to that of benzene and other benzenoids in reactions with 12-electron-particles CpM + (where M = Fe, Ru). Accordingly a hypothesis was made that Cp 3 Rh 3 (μ-CO) 3 behaves as a typical benzenoid system. Cationic half-sandwich and sandwich clusters were synthesized during the interaction of Cp 3 Rh 3 (μ-CO) 3 with cationic particles PPh 3 M + (where M = Cu, Ag, Au) and (CH 3 CN) 4 M + (where M = Cu, Ag).

Tetrahedral cationic cluster [MRH3(η-C5R5)(η-C5H5)3(μ3-CO)3]PF6 (M = Fe, R = H; M = Ru, R = H, Me) were synthesized by reaction of [Fe(η-C5H5)(η-Arene)]PF6 or [Ru(η-C5R5)(MeCN)3]PF6 with Rh3(η-C5H5)3(μ-CO)3. Their structure was confirmed by IR and NMR spectroscopy as well as by an X-ray diffraction study of [RuRh3(η-C5Me5)(η-C5H5)3(μ3-CO)3]PF6.

Hexanuclear rhodium carbonyl cluster, Rh6(CO)16, catalyzes benzene hydroxylation with hydrogen peroxide in acetonitrile solution. Phenol and (at lower concentration) quinone are formed with the maximum attained total yield and turnover number 17% and 683, respectively. Certain other rhodium carbonyl complexes, containing cyclopentadienyl ligands, Rh2Cp2(CO)3 and Rh3(CpMe)3(CO)3, are less efficient catalysts. Cyclopentadienyl derivatives of rhodium which do not contain the carbonyl ligands, Rh(CpMe5)(CH2CH2)2, RhCp(cyclooctatetraene) and Rh2Cp2(cyclooctatetraene) turned out to be absolutely inactive in the benzene hydroxylation. Styrene is transformed into benzaldehyde and (at lower concentration) acetophenone and 1-phenylethanol. Copyright © 2008 John Wiley & Sons, Ltd.