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The structure and mechanical properties of cast and powder materials of the Ti - Al - Si system are studied. It is established that eutectic compositions of this system display superior strength properties to existing heat-resistant titanium alloys.

The mass spectra of eight compounds beloning to the class of linear furo- and dihydrofurocoumarins have been studied. A scheme of the fragmentation of these substances under the action of electron impact has been proposed. It has been shown that the mass-spectrometric method permits acyl derivatives of oreoselone to be distinguished reliably from acyl derivatives of dihydrooreoselol and the latter series of substances from derivatives isomeric with them belonging to the class of dihydrofuro- and dihydropyranocoumarins.

The mass spectra of six compounds belonging to the class of terpenoid coumarins and of four of their deuterium analogs have been studied. Decomposition pathways for these substances under the action of electron impact have been suggested. It has been shown that from the mass spectra of compounds of this series it is possible to determine their molecular weights and, in atomic mass units, the weights of their terpene moieties, and also to establish the presence of hydroxy and acyloxy groups in the bicyclic terpene moiety.

The exploitable preparation tanacin represents a quantity of biologically active substances. In its composition are flavonoids [i, 2] and phenol carboxylic acids (caffeic, chlorogenic, isochlorogenic) while the main component is the flavonoid aglycone luteolin. To standardize the preparation it is necessary to develop methods for the quantitative determination of total flavonoids and phenol carboxylic acids in the substance and in the plant raw material.

1. It is shown that the most reliable values of the parameters σ0 and Ky in the equation of grain boundary strengthening can be obtained from the dependency of the true limit of elasticity σe on the grain size D−1/2. 2. The concept of the normalized coefficient Ky/σ0 is introduced, which allows one in the first instance to illustrate the general nature of grain boundary strengthening in metals with various types of crystallographic lattices, and in the second, to evaluate the contributions to grain boundary strengthening due to grain orientation in polycrystalline materials and segregation effects. 3. In accordance with the proposed scheme of strain hardening in polycrystalline bcc metals, once a dislocation cell structure forms, all grain sizes experience similar hardening effects. At this stage, the effect of the grain size on the level of the flow stress is due to the contribution of grain boundary strengthening to the size of the true limit of elasticity.

1. Dispersed zirconium nitrides in amounts up to 4 vol. % lead to substantial strengthening of niobium without notably reducing the low-temperature ductility. The strength-to-weight ratio of the alloys is at the same level as that of the best niobium alloys. 2. The ratio of the atomic percentages of zirconium and nitrogen in the alloy can be used as the criterion of workability. With a ratio of 1.6–1.7 the alloys are ductile in the cast condition at room temperature, and at temperatures down to −196° after annealing (at 1300° for 1 h). At ratios larger than 1.7 the strength characteristics decline. 3. Dispersed zirconium nitrides effectively prevent secondary recrystallization at temperatures up to 1600–1700°, at which noticeable growth of the particles begins.

1. It has been established that acetylpectolinarin, a new flavonoid from some species ofLinaria, is 7-[6-O-(4-acetyl-α-L-rhamnopyranosyl)β-D-glucopyranosyl]-5,7-dihydroxy-4′,6-dimethoxyflavone.

1. It is shown that different values of compressive and tensile yield stresses (the SD effect) are exhibited not only by dispersion-hardened alloys with oxides but also by various refractory metal alloys strengthened with carbides and nitrides, the magnitude of the SD effect being related to the morphology of the disperse particles. 2. A study was made for the first time of the variation of the magnitude of the SD effect, which was observed in a wide temperature range, right up to 0.55Tm of the alloy matrices, with temperature. The shape of the SD effect vs temperature curve is explained by considering the brittle-to-tough transition in a narrow zone of material adjacent to a phase boundary.

1. We studied the temperature dependence of the mechanical properties and fracture surface relief of a dispersion-hardened vanadium alloy with a strong interface within the temperature range −196 to 1500°C. 2. It was shown that the dispersed nitride phase plays a significant role in processes of brittle and ductile fracture. 3. A model was proposed, according to which numerous microcracks formed upon the fragmentation of nitride particles during plastic deformation may, depending on temperature and stress level, cause either cleavage fracture, or ductile fracture by the mechanism of void coalescence at a relatively low level of strain. A completely ductile fracture after a significant amount of plastic strain is possible only when the cracks formed with the fragmentation of particles do not propagate into the matrix.

From the epigeal part ofInula japonica Thunb. a new sesquiterpene lactone has been isolated which we have called inulicin. Structure (I) is proposed for it.

1. The structure of a new triterpene glycoside from the roots ofCalendula officianlis L. — calenduloside A—has been established as the 3-O-[O-β-D-galactopyranosyl-(1→4)-β-D-glucopyranoside] of oleanolic acid. 2. The 3-O-β-D-glucopyranoside of oleanolic acid has been isolated fromC. officialis for the first time.

A new coumarin has been isolated from the roots ofSeseli sessiliflorum for which the structure of 3′-angeloyloxy-2′,2′-dimethyl-4′-(trans-3-methylthioacryloyloxy)-3′, 4′-dihydropyrano-5′,6′:8,7-coumarin has been proposed. This is the first time that esters of 3-methylthioacrylic acid have been found in the coumarin series.

1. The structre of two new terpenoid coumarins have been established: colladin, C26H32O5, with mp 153–154° C (from ethanol), [αl D 22 - 65 (c 0.45; chloroform and colladonin, C24H30O4, mp 158.5–160° C (from ethanol), [α] D 22 -5-° (c 0.60; chloroform). 2. The structures of the coumarins badrakemin, samarcandin, and samarcandone have been corrected.

The mass spectra of 13 3′,4′-dihydroxy, 3′-hydroxy-4′-methoxy-, 3′-acyloxy-4′-methoxy-, and 3′,4′-diacyloxydihydropyranocoumarins have been studied. Schemes of the decomposition of these compounds leading to the formation of the main fragments in their mass spectra have been proposed. It has been shown that the mass spectra of (V–XIII) indicate whether the acyloxy groups are attached to position 3′ or 4′ of the dihydropyran ring. characteristic fragments with m/e 261, 245, 244, 243, 230, 229, 228, and 227 have been found, the positions and relative intensities of which form distinguishing features of the mass spectra of the diacyl derivatives of khellactone.

From the epigeal part ofInula britannica L. a new sesquiterpene lactone has been obtained — britannin, with the composition C19H26O7, mp 192–194°C (from ethanol). [α]D20–26° (c 5.0; chloroform). Structure (I) has been proposed for it.

On the basis of chemical reactions and spectral data, the structures of the umbelliferone ethers of 3-oxo-1,2,5,9-tetramethyldecal-5-ylmethanol and of 3-hydroxy-1,2,5,9-tetramethyldecal-5-ylmethanol have been proposed for kamolone and kamolol, respectively.

Structure (I) is proposed for stizolin — a sesquiterpene lactone fromStizolophus balsamita.

The mass spectra of six compounds have been obtained: kamolone, kamolol, [D3]kamolone, [D]kamolol, kamolol acetate, and the terpene diol derived from kamolol. The fragmentation of these compounds under the action of electron impact have been discussed. The mass spectra of kamolone and kamolol agree well with the structures provided for them previously.

From the roots ofLibanotis buchtormensis (Fisch.) D.C. have been isolated the furocoumarins bergapten, isoimperatorin, a pyranocoumarin, xanthogallol, and a new coumarin buchtormin C19H20O5, for which the structure (+)-3′-(β,β-dimethylacryloxy)-2′,2′-dimethyl-3′, 4′-dihydropyrano-5′, 6′:8, 7-coumarin has been proposed and confirmed by synthesis.

From the roots ofSeseli sessiliflorum Schrenk a new chromone has been isolated for which the structure of 2′,2′-dimethyl-3′-(3-methylthioacryloyloxy)-3′,4′-dihydropyrano-5′,6′:6,7-(5-hydroxy-2-methyl) chromone has been proposed. It is the first representative of this group of natural compounds containing sulfur.

The mass spectra of the following six linear monohydroxy- and monoacyloxydihydrofurocoumarins have been studied: marmezin (I), [D]marmezin (II), O-acetylmarmezin (III), deltoin (IV), pranchimgin (V), and seseliflorin (VI). It has been shown that it is possible by the mass-spectrometric method of analysis to determine the molecular weights of the acids the acyl radicals of which are present in these substances, to distinguish the acyl radical of angelic acid from that of senecionic acid, and also to distinguish this class of compounds from the angular dihydrofurocoumarins and from the angular and linear dihydropyranocoumarins isomeric with them.

The mass spectra of six compounds belonging to the class of angular and linear 4′-acyloxy-5′-(1-acyloxy-1-methylethyl)-and 4′-methoxy-5′-(1-acyloxy-1-methylethyl)dihydrofurocoumarins have been obtained. It has been shown that from the mass spectra of this class of compounds it is possible to determine the molecular weights of the acids correspnding to the acyl radicals that they contain, the position of attachment of the dihydrofuran ring to the coumarin ring, and the positions of the acyl residues, and also to distinguish this class of substances from the class of diacyloxydihydropyranocoumarins isomeric with it.

The structure of primflaside, a new flavonol trioside isolated from the leaves ofPrimula turkestanica has been established as quercetin 3-O-α-L-arabopyranosyl-(1 → 2)-O-α-L-arabofuranosyl-(1 → 4)-β-D-glucopyranoside.

The relative configurations of kamolol and kamolone have been established by the PMR method using paramagnetic shift reagents.

The structures of salts of N-methylquinol-2- and -4-one are considered, using their IR spectra. It is shown that formation of salts from N-methylquinolones is accompanied by protonation of the carbonyl group. The problem of relating the 1500–1700 cm−1 band in the IR spectrum of N-methylquinol-4-one is considered.

From the roots ofFerula penninervis Rgl. et Schmalh. have been isolated umbelliferone (7-hydroxycoumarin) and two new coumarins: a ketone with the composition C24H30O4, mp 191°–192° C and an alcohol C24H32O4, mp 141°–142° C, which have been named kamolone and kamolol, respectively.

The mass spectra of ten angular and linear dihydropyranocoumarins without substituents and with hydroxy and acyloxy substituents in position 3 of the dimethylchroman ring have been studied. Depending on the presence and nature of these substituents the mass spectra of the compounds considered have different relative intensities of the fragments with m/e 228, 213, 176, 175, 83, and 85, which permits mass spectrometry to be used in this group of compounds for structural-analytical purposes.

A new flavonoid glycoside, 3-β-D-glucopyranosyloxy-4′,5,7-trihydroxy-8-methoxyflavone has been isolated from the flowers of Crataegus pinnatifida.

A chromatophotometric method for the quantitative determination of ergometrine in rye ergots is proposed.

According to literature information on the physicochemical constants of peucenidin and 9-acetoxy-O-senecionyldihydrooroselol, the results of a comparison of NMR spectra and mass spectra, and also a study of the mass spectra of model compounds, it has been established that these substances are identical.

A new anthraglycoside with the composition C26H28O14 and mp 210–212°C, lucidin primeveroside, has been isolated from the roots ofRubia iberica C. Koch.

From the roots ofSeseli sessiliflorum Schrenk. we have isolated a new dihydrofurocoumarin C18H18O5S for which the structure 5′-[1-methyl-1-(trans-3-methylthioacryloyloxy)ethyl]-4′,5′-dihydrofuro-2′,3′:7,6-coumarin is proposed.

1. A new sesquiterpene lactone, “stizolicin,” has been isolated fromStizolophus coronopifolius (Lam.) Cass.