Positive projections and conditional mathematical expectations

One indicates how to construct the reduction of an arbitrary positive projection in to a strictly positive one and one proves that the latter is almost the operator of the conditional mathematical expectation relative to some -sub-algebra. More exactly, one shows a method of selecting from a strictly positive projection an operator of conditional mathematical expectation type (this concept is introduced in the paper).Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 47, pp. 172–174, 1974.     

Acousto-Optic Properties of Germanium-, Selenium-, Silicon-, and Tellurium-Based Alloys

Optics and Spectroscopy - Acoustic, optical, and acousto-optic properties of amorphous germanium-, selenium-, silicon-, and tellurium-based alloys have been studied. The velocities of longitudinal...     

Heterolaser frequency tuning under the action of ultrasonic waves

A new principle of the diode laser frequency tuning has been developed and implemented. According to this, the laser frequency is tuned by alternating strain in the active region of an InGaAsP/InP laser heterostructure emitting in a wavelength range of 1.3–1.8 µm. The strain is induced through the excitation of bulk ultrasonic waves in these heterostructures by means of a specially developed technique. Data on the influence of the alternating strain, induced by the bulk ultrasonic waves, on the spectral characteristics of laser radiation are presented. Estimates based on these data show that the frequency tuning range amounts to ΔF≈110 GHz for an acoustic wave with the frequency f=6.5 MHz and a power of about 1 W.     

NMR analysis of oils from pine nuts (<Emphasis Type="Italic">Pinus sibirica</Emphasis>) and seeds of common pine (<Emphasis Type="Italic">Pinus silvestris L.</Emphasis>)

We studied the fatty-acid composition of oils from pine nuts and seeds of common pine using PMR and ¹³C NMR and gas chromatography. We found that the main components of the glycerides are palmitic, stearic, oleic, linoleic, γ-linolenic, pinolenic, and cis-9-eicosenoic acids. The oils contain about 2% sn-1,2-diacylglycerides in addition to triglycerides. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 4, pp. 528–532, July–August, 2007.     

Photochemical chlorination of nanodiamond and interaction of its modified surface with C-nucleophiles

A procedure for the photochemical chlorination of nanodiamond by molecular chlorine in the liquid phase was proposed. This process was studied quantitatively for the first time. Hydrolytic stability of the chlorinated nanodiamond surface in air and in a 0.05 M solution of NaOH was determined. A possibility of disintegration of the initial aggregates (<60 μm) to finer aggregates (<200 nm) was shown. The reactions of a series of C-nucleophiles (organolithium reagents, CN⁻ ion) with the chlorinated surface were carried out. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2130–2137, December, 2006.     

The theory of non-linear acoustical noise amplification in piezoelectric semiconductors

The theory of non-linear acoustical noise amplification in piezoelectric semiconductors is developed on the basis of the rigorous equation for the phonon distribution function. The theory explains shift of the noise intensity maximum in q-space towards small values of q.     

Structure and dynamics of photoactivatable adenylyl cyclase

Russian Chemical Bulletin - The full-atom 3D model of the dimer of the photoregulated adenylyl cyclase is constructed. It contains a molecule of flavin mononucleotide chromophore in the...     

Biosensors Based on Graphene Nanomaterials

Moscow University Chemistry Bulletin - This review is devoted to the development, properties, and application of biosensors based on graphene nanomaterials. It is shown that such biosensors are...