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First results of new trembling aspen (Populus tremula L.) special factorial crosses are presented. At first, productive parent trees were selected: five maternal and five paternal trees without symptoms of heart rot and one tree with fruiting bodies of this fungal attack. The results of phenotypic and genotypic analyses of parent trees, their compatibility, and growth performance are presented. The analysis of the hybrid seedlings’ survival and their growth performance on open ground are shown. Estimates of general and specific combining abilities of the parent trees were carried out and potentially best hybrid families and seedlings were selected.

This paper examines the generation of high-frequency picosecond pulse trains as a result of modulation instability of wave packets with a large phase modulation depth and small amplitude modulation depth. We demonstrate that intermediate amplification of such wave packets and subsequent phase-to-amplitude modulation conversion lead to the formation of pulses with peak powers orders of magnitude higher than their initial power. The corresponding pulse generators can be used to generate a line spectrum.

Chiral ferrocene-containing iminoarylphosphite ligands based on 4,4′-dimethoxy-6,6′-di-tert-butyl-biphenyldiol-2,2′ and their chelate complexes with Rh(I) and Pd(II) were synthesized for the first time. They were shown to be perspective reagents in the reactions of asymmetric allyl substitution. The Pd-catalyzed alkylation of 1,3-diphenylallylacetate with dimethyl malonate results in a 87% enantiomer excess (ee), while in sulfonylation of 1,3-diphenylallylacetate with sodium para-toluenesulfinite, this figure amounts to 67%. The results obtained were compared with coordination and catalytic efficiency of a less sterically hindered ferro-cenyliminophosphite based on pyrocatechol. The compositions and structures of new compounds were determined by the 1H, 13C, 31P NMR, IR, mass spectrometry (EI, FAB, and electrospray techniques), and elemental analysis.

A chiral P,N-bidentate aryl phosphite ligand containing peripheral (R)-(+)-camphor-derived ketimine and its rhodium(I) and palladium(II) chelate complexes were synthesized for the first time. These compounds were found to be suitable for asymmetric allylic substitution. The Pd-catalyzed sulfonylation of 1,3-diphenylallyl acetate with sodium p-toluenesulfinate gave the product in 73% ee; in the alkylation of the same substrate with dimethyl malonate, the eewas 94%. These eevalues are higher than the enantioselectivity achieved with the known phosphine analogs.

A chiral iminophosphite ligand based on biphenyl-2,2"-diol and its chelates with rhodium(i) and palladium(ii) were synthesized for the first time. Successful use of these compounds in asymmetric allylic substitution was demonstrated. The enantioselectivity of palladium-catalyzed alkylation of methyl pent-3-en-2-yl carbonate with dimethyl malonate reached 70%, that in the alkylation of 1,3-diphenylallyl acetate with dimethyl malonate was 88%. In the rhodium-catalyzed sulfonylation of 1,3-diphenylallyl acetate with sodium p-toluenesulfinite, the enantioselectivity was 56%.

The reaction of (4S,9S)-4,9-diethyl-2,11-dioxa-5,8-diaza-1λ⁵-phosphatricyclo[6.3.0.0^1.5]undecane (1) with [Pt(COD)Cl2] (COD = cycloocta-1,5-diene) at 0 °C gave [(1,2:5,6-η)-1,5-cyclooctadiene][(4S,9S)-4,9-diethyl-5H-5,8-diaza-2,11-dioxa-1λ⁵-phosphatricyclo[6.3.0.0^1.5]undecyl-1]chloroplatinum chloride (2). If the reaction was performed in the presence of AgBF4, the corresponding BF4^- salt (4) was isolated. Complex 2 was converted to cis-dichloro{(4S,9S)-4,9-diethyl-2,11-dioxa-5,8-diaza-1-phosphabicyclo[6.3.0]undecane-P,N}platinum (3). Variable-temperature ³¹P NMR studies of complexes 2 and 4 have been carried out in the range from −93 to 50 °C. The structure of compound 4 has been determined by X-ray crystallography. Complex 4 has a slightly distorted trigonal-bipyramidal geometry around the phosphorus, with the platinum fragment in the equatorial position. The P−Nax bond distance is 2.002(5) Å. The Pt atom exhibits a nearly square-planar coordination geometry.

New chiral oxazoline-containing phosphoramidite was synthesized and its complex formation with rhodium(i) and palladium(ii) was examined. The new ligand is a highly efficient chiral inductor (eeup to 92%) in palladium-catalyzed asymmetric sulfonylation of 1,3-diphenylallyl acetate with sodium p-toluenesulfinate.

The complex formation of bi- and tricyclic hydrophosphorane derivatives of isoleucinol with [Pt(COD)Cl2], [Rh(CO)2Cl]2, and [Rh(THF)2(COD)]+BF4–(COD is cycloocta-1,5-diene) was investigated. In all cases, bicyclic hydrospirophosphorane selectively forms the metal chelates [M(η2-P∩N)(X)Cl] (M = Pt, X = Cl; M = Rh, X = CO) and [Rh(η2-P∩N)(COD)]+BF4–. («∩» denotes the residue of the hydrospirophosphorane ligand, which does not contain the P and N atoms). In addition, tricyclic hydrophosphorane (L) generates the phosphoranide complexes [Pt(η1-L)(COD)Cl]+Y–(Y = Cl or BF4). The structures of the new compounds were established by IR spectroscopy, 31P, 13C, 1H, 2H, 11B, 19F, and 195Pt NMR spectroscopy, and plasma-desorption and electrospray ionization mass spectrometry. The possible mechanism of coordination of hydrophosphoranes is discussed.

P,N-Bidentate (S)-2-(anilinomethyl)pyrrolidine derivatives and their complexes with rhodium(i) and palladium(ii) were synthesized. It was demonstrated that these compounds can be used in the Pd-catalyzed asymmetric allylation for the synthesis of chiral methyl 2-phenyl-2-(2-phenyl-o-carboranyl-1)pent-4-enoate.

The results of experimental estimation of the fulfillment of the local thermodynamic equilibrium (LTE) criterion for the plasma generated by laser pulses of various duration at the surface of a solid target placed in a gaseous atmosphere at standard pressure are given in the present paper. The fulfillment of all the LTE criteria is demonstrated for an ensemble of neutral atoms contained in the plasma generated by a giant laser pulse or by a laser pulse whose complex shape represents several giant pulses against the background of free-running laser oscillations. The plasma excited by the radiation of a Nd : YAG laser with energy ≤ 0.4 J per pulse is examined. We have recorded a resonance broadening of atomic Al and Mg lines. This has allowed us to estimate the density of neutral atoms contained in a plasma plume.

Abstract: This article reports the results of an experimental investigation of the basic mechanisms that cause the broadening of emission lines of a laser-induced plasma generated on the surface of rigid targets in a gaseous atmosphere. The contribution of Stark and resonance mechanisms of emission-line broadening for the resonance doublet Al I 3s23p2P3/2,1/2-3s24s2S1/2 and triplet Mg I 3s3p3P 0,1,20 -3s4s3S1 is discussed. The concentrations of neutral Al atoms in the laser-induced plasma are evaluated by the magnitude of resonance line broadening.

1.Differences in the catalytic activity of metallocene dichlorides of subgroups IVB-VIB in the amalgam reduction of carbon monoxide are due to thermodynamic factors determining the impossibility of amalgam reduction of the catalyst-substrate complex (subgroup IV) and differences in the stability of the corresponding metallocene (subgroups VB and VIB).2.Amalgam reduction of carbon monoxide, bound in a complex with metallocene, occurs under conditions of transfer of the first electron against the potential gradient.

We briefly summarize the reported anomalous effects in deuterated metals at ambient temperature commonly known as “cold fusion” (CF) with an emphasis on the latest experiments, as well as the theoretical basis for the opposition to interpreting them as cold fusion. Then we critically examine more than 25 theoretical models for CF, including unusual nuclear and exotic chemical hypotheses. We conclude that they do not explain the data.

A prototype of new instrument is under construction as a part of Russian Mars program to search for bioorganic compounds and microorganisms which might be frozen in rock under the places where the traces of water were found or near the poles of Mars. The proposed instrument consists of a quadrupole mass spectrometer (QMS) to detect chemical compounds and a fluorescent microscope system (FMS) to detect organisms and bioorganic compounds in bulk.

Conclusions High-porosity graphite contains two regions in which the speed of the USO varies with the pore size. When the pores are small relative to the ultrasonic wavelength, the USO speed increases within increase in the pore diameter to about 400µ (ratio of the USO wavelength to the mean pore diameter?/¯D=3–4) and then decreases.

Reversible poisoning of the catalysts for ammonia synthesis by oxygen has been used to eliminate the pyrophoric nature of the reduced catalysts via their treatment by the mixtures of nitrogen, hydrogen or helium with oxygen at catalysis temperatures. Kinetic studies of oxygen sorption, catalyst structure, activity and stability to the secondary oxidation of the samples partially oxidized at various temperatures have revealed that the optimum temperatures to eliminate the pyrophoric effect are 673–773 K.

Heats of oxygen adsorption on an industrial Ca-IB type catalyst for ammonia synthesis have been measured at 20°C. Participation of various forms of adsorbed oxygen (adsorption heats of 420 kJ/mol and below 84 kJ/mol) in the formation of a passivating (stabilizing) catalyst layer has been found.

The surface topography and elemental composition of the near-surface layers of a reduced passivated catalyst for ammonia synthesis have been studied on a scanning electron microscope in the initial state and after high-temperature oxygen treatment as well as removal of the alkali promoter.

Electrochemical reduction studies of dinitrogen catalyzed by Ti(OH)3−Mo(III) in an alkaline methanol solution on a mercury cathode show that the maximum yield of hydrazine (4%) and ammonia (43%) is observed at 0.5 mA/cm2 current density. In experimental conditions it corresponds to the zero-charge potential of sodium amalgam (−1.86 V).

The effect of a phosphorus-containing epoxy oligomer on the properties of an organoplastic fabricated by the pultrusion process was investigated. It was found that the material is difficultly inflammable, self-extinguishing, and is as good as the starting flammable organoplastic with respect to the level of the physicomechanical properties. The positive effect of additional heat treatment (155–250°C temperature range) of samples of the organoplastic on their physicomechanical properties was demonstrated.

Conclusions Castings having a thickness up to 65 mm and an apparent density slightly higher than that of similar specimens slip-cast in plaster of Paris molds were formed by the electrophoretic method from high-concentration suspensions of quartz glass.

Conclusions In an investigation of the influence of the principal factors on the rate of slip casting quartz ceramics it was established that the density (porosity) of the deposited cast body is the main determining factor in the casting rate. The density of the body depends on the degree of stabilization, the pH, and the granularity of the slip suspension, and on the use of vibration. The casting rate may vary tenfold with the porosity of the casting. The factors which increase the density of the casting reduce the casting rate to the same extent, and vice versa.

New quinine-based polyfunctional aryl phosphite was synthesized. The phosphorus center in the new compound is characterized by a large cone angle (θ = 190°). The new compound can be used in the Pd-catalyzed enantioselective rearrangement of cyclic O-allylic thiocarbamate into S-allylic thiocarbamate in an optical yield of up to 47% with a quantitative conversion.

Abstract: A technology to make railroad rails of steel NE76V (TU 14-1-5233-93) for low-temperature service has been developed and successfully introduced at the Kuznetsk Metallurgical Combine. The technology is the first of its kind in this country and has no counterpart in world metallurgy. Rails of this steel have an impact toughness greater than 20 J/cm2 at −60°C.

Conclusions 1.An increase in the temperature of passivating the Fe catalyst for the synthesis of ammonia, facilitates the formation of a more firmly bound oxygen to the surface of the catalyst.2.The adsorption capacity of the catalyst toward oxygen increases with increase in the temperature.3.Adsorption centers that differ in their properties are present on the surface of the catalyst, and only a part of the centers bears responsibility for diffusion of the adsorbed oxygen into the bulk of the catalyst.

Review: 196 refs.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.