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All Hamiltonian non-abelian Painlevé systems of P1-P6type with constant coefficients are found. For P1-P5systems, we replace an appropriate inessential constant parameter with a non-abelian constant. To prove the integrability of new P3′and P5systems thus obtained, we find isomonodromic Lax pairs for them.

Reactivity of transition metal complexes containing the redox-active gallylene (dpp-bian)Ga ligand (dpp-bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) toward isocyanide, isocyanate, isothiocyanate, and ketene substrates is described. The reaction of [(dpp-bian)GaCr(CO)5] (1) with tBuNC results in a dative complex [(dpp-bian)Ga(CNtBu)Cr(CO)5] (2), while compound [(dpp-bian)GaCr(CO)5]2[Na(THF)2]2(3) reacts with tBuNC to give the coordination polymer [(dpp-bian)GaCr(CO)5][Na(CNtBu)(THF)]n(5). Treatment of [(dpp-bian)GaCr(CO)5]2[Na(THF)2]2with an excess of PhNCO results in trimerization of the latter and formation of complex [(dpp-bian)GaCr(CO)5][Na(PhNCO)3(Et2O) (DME)] (4). [(dpp-bian)GaFeCp(CO)2] (7) treated with Ph2CCO or PhNCS results in cycloaddition products [(dpp-bian)(Ph2CCO)GaFeCp(CO)2] (8) and [(dpp-bian)(PhNCS)GaFeCp(CO)2] (9). The formation of 2and 9was found to be reversible, which offers a means for facile regulation of transition metal center reactivity and cooperative substrate activation. New compounds were characterized by EPR (2), NMR (4, 8, and 9), and IR spectroscopy (2, 4, 5, 8, and 9). The molecular structures of 2, 4, 5, 8, and 9were established by single-crystal X-ray diffraction analysis. Electronic structures of the compounds have been examined by DFT calculations.

The reaction of Cl2GaH with a sodium salt of the dpp-Bian radical-anion (dpp-Bian•–)Na (dpp-Bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) affords paramagnetic gallane (dpp-Bian•–)Ga(Cl)H (1). Oxidation of (dpp-Bian2–)Ga–Ga(dpp-Bian2–) (2) with N2O results in the dimeric oxide (dpp-Bian•–)Ga(μ2-O)2Ga(dpp-Bian•–) (3). A treatment of the oxide 3with phenylsilane affords paramagnetic gallium hydrides (dpp-Bian•–)GaH2(4) and (dpp-Bian•–)Ga{OSi(Ph)H2}H (5) depending on the reagent’s stoichiometry. The reaction of digallane 2with benzaldehyde produces pinacolate (dpp-Bian•–)Ga(O2C2H2Ph2) (6). In the presence of PhSiH3, the reaction between digallane 2and benzaldehyde (2: PhSiH3: PhC(H)O = 1:4:4) affords compound 4. The newly prepared complexes 1, 3–6consist of a spin-labeled diimine ligand–dpp-Bian radical-anion. The presence of the ligand-localized unpaired electron allows the use of the ESR spectroscopy for characterization of the gallium hydrides reported. The molecular structures of compounds 1, 3–6have been determined by the single-crystal X-ray analysis.

Reactivity of low-valent AlIIspecies containing redox-active dpp-dad or dpp-Bian ligand (La= dpp-dad = [(2,6-iPr2C6H3)NC(CH3)]2; Lb= dpp-Bian = 1,2-[(2,6-iPr2C6H3)NC]2C10H6) toward nitrogen-rich substrates is described. Reactions of dialumanes [L2–Al–AlL2–] (La, 1a, or Lb, 1b) with azides (Me3SiN3, BenzylN3) or azobenzene at room temperature lead to the facile elimination of dinitrogen (in the case of azides) and formation of dimeric imido-complexes [L•–Al(μ2-NR)2AlL•–] (2a–2d). During the reaction, the initially dianionic ligands (L2–) and AlIIions are oxidized into monoanions (L•–) and AlIIIin the products, respectively, while the [NR]2–imides are produced by a four-electron reductive cleavage of the N═N double bond of azides or azo compounds. The monoanionic α-diimine ligands in 2can be reduced again by Na, yielding analogous products with (La)̇•–/(La)2–or (La)2–/(La)2–ligands (3, 4a, and 4b). Treatment of 1awith benzyl azide at −30 °C in the presence of Na results in [(La)2–Al(μ2-N3Benzyl)2Al(La)2–]·[Na(THF)]2(5), with unprecedented bridging triazene groups, while reaction with trimethylsilyldiazomethane (Me3SiCHN2) or diphenyldiazomethane (Ph2CN2) affords dinuclear complexes with doubly reduced diazo dianions as the bridges (6aand 6b). All the products were structurally and spectroscopically characterized. The results clearly demonstrate the unique reactivity of α-diimine-ligated dialumanes 1aand 1b, which can activate nitrogen-rich molecules by cooperation of metal and the redox ligand.

In the course of the study, we analyzed the development of the railway and road network and assessed the prospects of transport infrastructure development in the northern and Arctic regions of Russia. Besides, we reviewed processes of territory development with account for natural and climatic conditions. The article presents potential ways to overcome the specified problems related to the development of transport infrastructure and logistics in the northern and Arctic regions of Russia.

The reaction of dialane (dpp-Bian)Al–Al(dpp-Bian) (1) (dpp-Bian is dianion of 1,2-bis[(2,6-diisopropylphenyl)imino]-acenaphthene) with 1 mol equiv of 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (iPr2ImMe) results in the Al-carbene adduct (dpp-Bian)(iPr2ImMe)Al–Al(dpp-Bian) (3). In the course of the reaction of dialane 1with 2 mol equiv of 1,3-diisopropyl-4,5-dimethylimidazol-2-thione (iPr2ImtMe) a half of the thione amount undergoes a cleavage of sulfur–carbon double bond. In the product (dpp-Bian)(iPr2ImMe)Al(μ-S)Al(iPr2ImtMe)(dpp-Bian) (4) aluminum atoms coordinate carbene as well as thione ligands. Compound 4is thermally robust: no reduction of C═S bond in thione moiety by the dpp-Bian ligands could be observed in toluene for 24 h at 100 °C. Complex {(dpp-Bian)(iPr2ImMe)Al}2(μ-S) (5) was isolated from the reaction of dialane 1, iPr2ImMe, and iPr2ImtMe(1:1:1). The reaction of mononuclear (dpp-Bian)AlH(THF) (2) (THF = tetrahydrofuran) affords compound (dpp-Bian)AlH(iPr2ImMe) (6). Compounds 3–6were characterized by 1H NMR and IR spectroscopy; their molecular structures were established by single-crystal X-ray analysis.

Currently, the chemistry of organofluorine compounds is a leading and rapidly developing area of organic chemistry. Fluorine present in a molecule largely determines its specific chemical and biological properties. This thematic issue covers the trends of organofluorine chemistry that have been actively developed in Russia the last 15 - 20 years. The review describes nucleophilic substitution and heterocyclization reactions involving fluorinated arenes and quinones and skeletal cationoid rearrangements in the polyfluoroarene series. The transformations involving CF3-substituted carbocations and radical cations are considered. Heterocyclization and oxidative addition reactions of trifluoroacetamide derivatives and transformations of the organic moiety in polyfluorinated organoboranes and borates with retention of the carbon - boron bond are discussed. Particular attention is devoted to catalytic olefination using freons as an efficient synthetic route to fluorinated compounds. The application of unsymmetrical fluorine-containing N-heterocyclic carbene ligands as catalysts for olefin metathesis is demonstrated. A variety of classes of organofluorine compounds are considered, in particular, polyfluorinated arenes and 1,2-diaminobenzenes, 1-halo-2-trifluoroacetylacetylenes, a-fluoronitro compounds, fluorinated heterocycles, 2-hydrazinylidene-1,3-dicarbonyl derivatives, imines and silanes. The potential practical applications of organofluorine compounds in fundamental organic chemistry, materials science and biomedicine are outlined.The bibliography includes 1019 references.

The transport and magnetic properties of cation-substituted manganese sulphides CexMn1-ХS in the 4K - 450K temperature range in magnetic fields up to 90 kOe are studied. The hysteresis of curve magnetization for X=0.01 and nonlinear field behavior of the magnetization at X = 0.05, the sharp Curie temperature drop were found. The sharp maximum in the temperature dependence of resistivity was observed. The shift of the maximum temperature to low temperatures at cerium ion concentration increasing and in magnetic field was established. Model of orbital polaron for explanation of experimental datа was used.

The article suggests an approach to determine structural elements technical condition, based on the mathematical probabilistic apparatus of technical diagnostics. Diagnostics are performed using probabilistic methods of complex technical systems conditions recognition. Probabilistic parameters are calculated according to Bayes’s rule. The paper shows a diagnostics example of intermediate floor elements and systems in the old urban development building. Both the suggested method and information theory methods are used during diagnostics.

Abstract: Recent studies have shown that the proper treatment of ground-motion variability and, particularly, the correlation of ground motion are essential for the estimation of the seismic hazard, damage and loss for distributed portfolios. In this work we compared the effects of variations in the between-earthquake correlation and in the site-to-site correlation on probabilistic estimations of seismic damage and loss for the extended objects (hypothetical portfolio) and critical elements (e.g. bridges) of a network. Taiwan Island has been chosen as a test case for this study because of relatively high seismicity and previous experience in earthquake hazard modelling. The hazard and loss estimations were performed using Monte Carlo approach on the basis of stochastic catalogues and random ground-motion fields. We showed that the influence of correlation on parameters of seismic hazard, characteristics of loss distribution and the probability of damage depend, on one hand, on level of hazard and probability level of interest (return period) and, on the other hand, the relative influence of each type of correlation is not equal.

Abstract: The estimation of strength of shaking at a site from the initial P-wave portion of ground motion is the key problems for shortening the alert time of the earthquake Early Warning (EEW). The most of the techniques proposed for the purpose utilize (a) ground motion models based on the estimated magnitude and hypocentral distance, or (b) the interim proxies, such as initial vertical displacement P d . We suggest the instrumental Japan Meteorological Agency (JMA) intensity (JMAI) as a characteristic for fast estimation of damage potential in the EEW systems. We investigated the scaling relations between JMAI measured using the whole earthquake recordings (overall intensity) and using particular time intervals of various duration (2.0–8.0 s) starting from the P-wave arrival (preliminary intensity). The dataset included 3,660 records (K-NET and the KiK-net networks) from 55 events (M W 4.1–7.4) occurred in 1999–2008 in Japan. We showed that the time interval of 4–5 s from the P-wave arrival can be used for reliable estimations of the overall intensity with the average standard error of about 0.5 JMA units. The uncertainty in the prediction may be reduced by consideration of local site conditions or by development of the station-specific models.

Abstract: Taipei, the capital of Taiwan, suffered from destructive earthquakes four times during the 20th century (M L = 7.3 on April 15, 1909; M L = 6.8 on November 15, 1986; the Chi–Chi M L = 7.3 earthquake on September 21, 1999; and M L = 6.8 on March 31, 2002). Analysis of recorded data shows a strong dependence of spectral amplification in the Taipei Basin on earthquake depth and azimuth. At low frequencies (f < 3 Hz) significant larger amplifications are observed for shallow earthquakes as compared to intermediate depth events. The former ones also display strong azimuthal dependence. As structures with large response periods such as bridges and tall buildings are sensitive to these low frequencies the understanding of the associated wave effects within the basin and their role for site effect amplification is critical. The tool we employ is 3D finite-difference modeling of wave propagation of incident wave fronts. The available detailed model of the basin allows studying the wave effects. Modeling clearly reveals that basin edge effects as observed in data are related to surface wave generation at the basin edges with a high degree of azimuthal dependency. The reproduced site amplification effects are in qualitative agreement with the observations from strong motion data.

Determination of earthquake magnitude from the initial P-wave portion of ground motion is the key problems for Earthquake Early Warning (EEW). We analyzed performance of scaling relations between one of the frequently used early warning parameters, so-called characteristic period tCand moment magnitude MWin respect of (a) characteristics of datasets accumulated in various regions (earthquake depth, characteristics of network) and (b) variation of initial conditions applying for determination of the parameter tC(length of Pwave window, number of used stations). The used data contain strong-motion records from 110 earthquakes (moment magnitude range 4.4–7.6) occurred in Japan and Taiwan. We show that, although the standard error of regression tC= f(MW) in general becomes smaller with the increase of the length of P-wave window (PL) and the number (N) of averaged observations (stations), the uncertainty in estimation of MW given observed tC does not decrease further for PL > 3–4 seconds and N> 3–4 stations. The information about earthquake depth also plays an important role in reducing the uncertainty of magnitude estimations. The table of confidence limits for estimations of the moment magnitude MWbased on observations of the characteristic period tCis provided.

We establish and test a shake map methodology for intermediate-depth Vrancea earthquakes, based on seismological information gathered in Romania during recent years. We use region- (azimuth-) dependent attenuation relations derived from stochastic simulations of ground motions using spectral models of Vrancea earthquakes. Both region boundaries and Fourier amplification spectra for the characterization of seismic site effects are based on several hundred weak, moderate and strong-motion records and macroseismic intensity maps. We determine region-specific, magnitude- and distance-dependent amplification factors of peak values and instrumental intensity relative to rock. We interpolate recorded ground motions and ground motion estimates from the obtained amplification factors and attenuation relations for rock conditions. The resulting shake maps show a good agreement with macroseismic descriptions of moderate-sized and large Vrancea earthquakes, demonstrating the feasibility of a seismological approach to shake map generation. Unlike previous methodologies, this approach requires neither expensive assessments of geology-dependent site amplification factors, nor large numbers of strong-motion records. Our results are in good agreement with empirical topographic slope-site amplification relations, but give a better reflection of the abnormal attenuation of seismic waves in the Transylvanian region and the strong amplification in the Focsani basin.

Abstract: We present the regional ground-motion prediction equations for peak ground acceleration (PGA), peak ground velocity (PGV), pseudo-spectral acceleration (PSA), and seismic intensity (MSK scale) for the Vrancea intermediate depth earthquakes (SE-Carpathians) and territory of Romania. The prediction equations were constructed using the stochastic technique on the basis of the regional Fourier amplitude spectrum (FAS) source scaling and attenuation models and the generalised site amplification functions. Values of considered ground motion parameters are given as the functions of earthquake magnitude, depth and epicentral distance. The developed ground-motion models were tested and calibrated using the available data from the large Vrancea earthquakes. We suggest to use the presented equations for the rapid estimation of seismic effect after strong earthquakes (Shakemap generation) and seismic hazard assessment, both deterministic and probabilistic approaches.

A database containing records from nine large earthquakes in Japan, obtained by K-NET and KIK-net strong motion stations, was used for the analysis of two techniques for the estimation of instrumental seismic intensity from accelerograms. The first technique is the standard method for JMA intensity evaluation from filtered three-component accelerograms. The second technique is the so-called FAS-intensity, which was developed for MM and MSK scales and which is based on the correlation between levels of the Fourier Amplitude spectrum (FAS) and observed intensity. The relation between these two types of instrumental intensities (JMAIand spectral MMI) may be described by linear function for intensities larger than JMAI3.5–4 and MMI5.0–5.5, but large discrepancy arises at small intensities. The variation is most probably caused by differences in the spectral content of the ground motions, since the JMAIcalculation is sensitive to the spectral amplitude within a narrow frequency band around 0.5 Hz.

Abstract: Intermediate-depth earthquakes in the Vrancea region occur in response to stress generation due to descending lithosphere beneath the southeastern Carpathians. In this article, tectonic stress and seismicity are analyzed in the region on the basis of a vast body of observations. We show a correlation between the location of intermediate-depth earthquakes and the predicted localization of maximum shear stress in the lithosphere. A probabilistic seismic hazard assessment (PSHA) for the region is presented in terms of various ground motion parameters on the utilization of Fourier amplitude spectra used in engineering practice and risk assessment (peak ground acceleration, response spectra amplitude, and seismic intensity). We review the PSHA carried out in the region, and present new PSHA results for the eastern and southern parts of Romania. Our seismic hazard assessment is based on the information about the features of earthquake ground motion excitation, seismic wave propagation (attenuation), and site effect in the region. Spectral models and characteristics of site-response on earthquake ground motions are obtained from the regional ground motion data including several hundred records of small and large earthquakes. Results of the probabilistic seismic hazard assessment are consistent with the features of observed earthquake effects in the southeastern Carpathians and show that geological factors play an important part in the distribution of the earthquake ground motion parameters.

In the paper we consider several dynamical systems that admit a separation of variables on the algebraic curve of genus 4. The main result of the paper is an explicit formula for the action of these systems. It is obtained directly from the Hamilton–Jacobi equation. We find the action and a separation of variables for the Clebsch and the [font face='times new roman'][i]so[/i](4)[/font] Schottky Manakov spinning tops.

Empirical amplification functions for site classes B, C, and D in Taiwan were evaluated as the ratio between Fourier amplitude spectra of recorded accelerograms and spectra modeled for a hypothetical very hard rock (VHR) site. The approach allowed testing applicability of various spectral models in the studied region. More than 1,000 acceleration records obtained during 21 intermediate-sized and large earthquakes (ML>5.5), including the ML7.3 (MW7.6) Chi-Chi earthquake (21 September 1999) and the large aftershocks (ML6.8), were used. The evaluated amplification functions were compared with independent data, which were obtained recently for Taiwan, the western United States, and Greece. The prominent influence of geologic and geomorphologic factors on site amplification functions for the considered cases of rock (Class B), soft rock or very dense soil (Class C), and stiff soil (Class D) sites has been observed for the Taiwan region.

The paper describes an integrated approach to seismic hazard assessment, which was applied for the Taiwan region. First, empirical modelsfor ground motion estimation in the region were obtained on the basisof records from recent (1993-1999) earthquakes. The databaseincludes strong-motion data collected during the recent Chi-Chiearthquake (M=7.6, 21 September 1999) and large (M=6.8)aftershocks. The ground-motion database was also used for evaluationof generalised site amplification functions for typical soil classes(B, C and D). Second, the theoretical seismic catalogue (2001–2050)for the Taiwan region had been calculated using the 4D-model(location, depth, time) for dynamic deformation of the Earth' crustand 5D-model (location, depth, time, magnitude) for seismic process.The models were developed on the basis of available geophysical andgeodynamic data that include regional seismic catalogue. Third, theregion & site & time-dependent seismic analysis, which is basedon schemes of probable earthquake zones evaluated from the theoreticalcatalogue, regional ground motion models, and local site responsecharacteristics, has been performed. The seismic hazard maps arecompiled in terms of Peak Ground Acceleration (PGA) and ResponseSpectra (RS) amplitudes. The maps show distribution of amplitudesthat will not be exceeded with certain probability in condition oftypical soil classes during all possible earthquakes that may occur inthe region during time period of 2003–2025. The approach allowsintroducing new parameter that describes dependency of seismichazard on time, so-called ''period of maximum hazard''. Theparameter shows the period, during which every considered sitewill be subjected by the maximum value of ground motioncharacteristic (PGA or RS).

This note presents results of a pollen analysis of sea-ice snow samples collected in April-May 2002 by members of the Russian Northern Polar Station-2001. Pollen and spores are deposited with snow falling on Arctic sea ice, and by determining the plant species represented by these pollen and spores, information about atmospheric circulation patterns can be obtained.

The results of comparative studies of autofluorescence and 5-ALA-induced fluorescence of protoporphyrin IX, used in the diagnostics of early cancer of larynx and bronchi, are presented. The autofluorescence and 5-ALA-induced fluorescence images of larynx and bronchial tissues are analysed during the endoscopic study. The method of local spectrophotometry is used to verify findings obtained from fluorescence images. It is shown that such a combined approach can be efficiently used to improve the diagnostics of precancer and early cancer, to detect a primary multiple tumours, as well as for the diagnostics of a residual tumour or an early recurrence after the endoscopic, surgery or X-ray treatment. The developed approach allows one to minimise the number of false-positive results and to reduce the number of biopsies, which are commonly used in the white-light bronchoscopy search for occult cancerous loci.

The description of an experimental set-up for the study of the excitation energy distribution of fission fragments by means of coincident measurement of fission neutrons is presented. For every fission event the kinetic energy and mass of both fragments are registered simultaneously with the number of prompt neutrons emitted by each of the complementary fission fragments. With this set-up, the fission fragments are detected by a twin ionization chamber and the neutrons - by two large Gd-loaded liquid scintillator tanks.

The number of prompt neutrons emitted in the fission event have been measured separately for each complementary fragment in coincidence with fragment mass and kinetic energies in spontaneous fission of 252Cf, 244Cm and 248Cm. Two high efficient Gd-loaded liquid scintillator tanks were used for the neutron registration. Approximately 3 106fission events coincident with prompt neutron emission have been accumulated for each isotope. The mean neutron multiplicity, the dispersion and the covariance of the multiplicity distributions have been obtained as a function of fission fragment mass and kinetic energy. The neutron multiplicity data have been corrected for neutron registration efficiency, background and pile-up. Dependencies of the moments of the multiplicity distributions on the fragment mass and total kinetic energy for different mass bins, as well as mass and total kinetic energy distributions of the fission fragments are presented, discussed and compared for the different isotopes investigated. The results showed a different behavior of the moments of the multiplicity distribution depending on the fragment mass asymmetry that reflects changes in the dynamical effects for different fission modes.

This paper presents a revised method for estimating the seismic intensity (MMI or MSK scale) using Fourier amplitude spectra (FAS) of ground acceleration. The improvement of the recently proposed technique (Sokolov and Chernov 1998) has been made on the basis of the data, which were obtained recently during strong earthquakes that occurred throughout the world. The total amount of the used data (horizontal components of ground-motion recordings) is about 1,150 records, while the database of 300 recordings was used in the previous study. The method implies that the seismic intensity is determined by the level of ground motion spectral amplitudes in the frequency range of 0.4–13 Hz. The corresponding empirical relationships between FAS and each intensity level were developed. The method is validated by comparison of the results of the technique application with the empirical data, which have not been included in the database. The Romanian earthquakes (intermediate-depth events of 1977, 1986, and 1990) and the recent 1999 Hector Mine earthquake in southern California were used for this purpose. In general, the FAS intensity shows a good agreement with the reported intensity, and the average residuals do not exceed ±0.3 intensity units and standard deviation is about 0.4-0.6. Evaluation of seismic intensity distribution using region- and site-dependent spectral models, as well as calculation of instrumental intensity map for the recent 1999 Chi-Chi earthquake, Taiwan, show that the FAS intensity clearly reflects the regional (source scaling and attenuation relation) and local (soil response) peculiarities of ground motion.

In the Taiwan region, the empirical spectral models for estimating ground motion parameters were obtained recently on the basis of recordings of small to moderate (5.0≤ M L ≤6.5) earthquakes. A large collection of acceleration records from the recent M L 7.3 ( M W 7.6) Chi-Chi earthquake (20 September, 1999) makes it possible to test the applicability of the established relationships in the case of larger events. The comparison of ground motion parameters (peak accelerations and response spectra), which were calculated using the stochastic approach based on the modeled Fourier amplitude spectra, and the observed data demonstrates that the models may be successfully used for ground motion prediction for earthquakes of magnitudes up to M L =6.8-7.0 and hypocentral depth more than 10 km. To satisfy to the peculiarities of ground motion during shallow (depth less than 10 km) and larger ( M L >7.0) events, the models were revised.

The kinetics of the destruction of diisopropyl methylphosphonate (DIMP) in corona discharge has been studied using a flow tubular coaxial wire dielectric barrier corona discharge reactor. The identification and quantitative determination of DIMP, its destruction intermediates, and phosphorus-containing destruction products were performed using molecular beam mass spectrometry and gas chromatography/mass spectrometry. Active discharge power was varied in the range 0.01–5 W. The destruction products such as isopropyl methylphosphonate, methylphosphonic acid, and orthophosphoric acid were found on the reactor walls. The dependence of the extent of the destruction, D (D = 1 − X / X0, where X and X0 are DIMP mole fractions at the outlet and the inlet of the reactor), on the specific energy deposition Ex (Ex = PF⁻¹ X0⁻¹, where F is the carrier gas flow and P is the power dissipated in discharge reactor) was measured over the DIMP mole fraction range 60–500 ppm at the pressure of 1 bar and the temperature of 340 K. Over the range of the experimental conditions studied the destruction obeys the “pseudo-first-order” kinetic law: ln(1 − D) = −KEx. Plausible mechanisms of the destruction are discussed. It was concluded that ion mechanism is the major one responsible for the destruction process. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 331–337, 2002

We calculated peak ground accelerations and response spectra for the Taipei area using stochastic simulation technique on the basis of recently obtained empirical models. The source, path and site effects were characterized separately on the basis of the analysis of a large collection of ground-motion recordings obtained since 1991 in the Taiwan area. The simple ω-squared Brune's point-source model combined with regional anelastic attenuation (Q) and duration (τ0.9) models provide a satisfactory estimation of ground-motion parameters for rock sites. Effects of local site response are considered by means of empirical soil/bedrock spectral ratios calculated as ratios between spectra of actual earthquake records and those modeled for hypothetical “hard rock” site. The results of the simulation demonstrate that this combination of source, path and site response models provides an accurate prediction of “site- and region-dependent” ground-motion parameters for the Taipei basin for the broad range of earthquake magnitudes, distances and site conditions. The model, with a set of generic soil profiles, can be considered as an efficient tool for estimating of design input ground motion parameters in the Taipei basin both in deterministic (scenario earthquakes) and probabilistic (“site- and region-dependent” Uniform Hazard response spectra) seismic hazard assessment.

A two-channel monochromatic illuminator with only one diffraction grating and an original scanning system has been designed for multiple applications. This scanning system consists of two rotational plane mirrors that reflect light diffracted by a concave diffraction grating to the ±1 orders of the spectrum. The light reflected by the mirrors goes to two exit slits that correspond to two channels of the device. The positions of the centers of rotation of the mirrors are selected to produce minimal deviation of the direction of the light reflected during the scanning. The aberration characteristics of some variations in the optical mounting of the device made by use of spherical and toroidal holographic diffraction gratings recorded in stigmatic and astigmatic beams, the possibilities for application of the device for measuring the color sensitivity of the human eye, and the possibilities for measuring the efficiency of concave diffraction gratings, are also discussed.

We analyze the site response of the Taipei basin using the records obtained by the Taiwan Strong Ground Motion Instrumentation Program (TSMIP) network. Records of 66 earthquakes of M=2.6-6.5 with a hypocentral depth varying from 1 km to 118 km and hypocentral distances of up to 150 km are studied for 35 stations located within this triangle-shaped alluvium structure. The site response is obtained in terms of spectral ratios calculated by dividing of the site spectrum by the reference spectrum estimated for a hypothetical “very hard rock” site. The recently developed empirical source scaling and attenuation models for the Taiwan region are used for the reference spectra calculation. This approach allows us to evaluate the variability of spectral ratios due to uncertainties introduced by source and propagation path effects and variability in the site response itself. The characteristics of site response in the Taipei basin depend on the properties of soil deposits and, in general, may be described by 1-D models. However, there are some peculiarities of spectral ratios that show the influence of subsurface topography.

A collection of ground-motion recordings (1070 acceleration records) of moderate (5.1ML6.5) earthquakes obtained during the execution of the Taiwan Strong Motion Instrumentation Program (TSMIP) since 1991 was used to study source scaling model and attenuation relations for a wide range of earthquake magnitudes and distances and to verify the models developed recently for the Taiwan region. The results of the analysis reveal that the acceleration spectra of the most significant part of the records, starting from S-wave arrival, can be modelled accurately using the Brune's ω-squared source model with magnitude-dependent stress parameter Δσ, that should be determined using the recently proposed regional relationships between magnitude (ML) and seismic moment (M0) and between M0 and Δσ. The anelastic attenuation Q of spectral amplitudes with distance may be described as Q=225 ƒ^1.1 both for deep (depth more than 35 km) and shallow earthquakes. The source scaling and attenuation models allow a satisfactory prediction of the peak ground acceleration for magnitudes 5.1M6.5 and distances up to about 200 km in the Taiwan region, and may be useful for seismic hazard assessment. Copyright © 2000 John Wiley & Sons, Ltd.

We have studied a laser system with quick electronic tuning of the spectrum shape and continuous distribution. The proposed method is based on separate control of phase and amplitude spatial distributions of resonator transmittance. Evolution of the spectral function of the diffractively coupled dispersive resonators and the model for the formation of the resonator with the spectral function given by its moments are studied theoretically. The synthesis of continuous spectra is investigated experimentally in the laser with a novel control element including a spatial acousto-optic modulator and a tunable lens telescope.

In the bounds of the totally nonmetric model of gravitational interaction theory (gravidynamics) the strong field of a compact object (a collapsar) — an analogue to the black hole in general relativity — is investigated. In the case of utmost strong (for gravidynamics) collapsar, field a region filled, by matter (a bag) must have the radius equal tor*=GM/c2?10 km at the total collapsar massM?7M?. Only half of the collapsar mass is contained in the bag, the other one of its total energy (Mc2) is distributed in the space surrounding the bag in the form of ‘a coat’, i.e., in the form of continuous medium (a relativistic ‘gas’) of virtual gravitons. The object must have the surface (the bag surface) with absolutely definite physical properties. The potential of such a surface is finite (?+=-c2/2) and the particle mass finding itself in a bound state on the bag surface is two times less than the mass of the same particle in a totally free state. The bag surface can perform periodic oscillations (pulsations) with the periodGM/c2˜3×10-5 s. An energy density inside the bag with the utmost strong gravitational field or with an utmost dense ‘coat’ shrouding the bag is determined by gravitation theory constants only and depends on the distance to the bag centerr in the following way: e(r)=(c5/8pG)r-2. The bag matter in the case is most probably in the state of quark-gluon plasma.

From the point of view of a totally nonmetric model of the theory of gravitational interaction, i.e., in the bounds of a consistent dynamic description of gravitation (gravidynamics) a possibility is pointed out of additional loss of energy for the radiation of scalar gravitational waves. Such a radiation arises due to (in particular, periodic) variations, for example, spherically-symmetric pulsations, in a radiating system and is connected with time change of kinetic energy of system. The scalar gravitational ‘luminosity’ in gravidynamics is of the same order (~G/c5) as the system energy loss for the radiation of ‘usual’ tensor gravitational waves of general relativity. Perhaps, for a binary system with a nonzero eccentricity it is necessary to account for the influence of scalar radiation on a secular variation of the companion's orbit parameters. The contribution of the scalar radiation into a total gravitational ‘luminosity’ of the system with a radio pulsar PSR 1913+16 can be of the value about 2.2% of the radiation power of the tensor gravitational waves. It can have a considerable effect at measurements of the fall rate of orbital period (Pb) of the binary system, and the corresponding contribution intoPb can be equal to ?Pb˜-0.053x10-12 ss-1.

Abstract:: This paper surveys the classification of integrable evolution equations whose field variables take values in an associative algebra, which includes matrix, Clifford, and group algebra valued systems. A variety of new examples of integrable systems possessing higher order symmetries are presented. Symmetry reductions lead to an associative algebra-valued version of the Painlev� transcendent equations. The basic theory of Hamiltonian structures for associative algebra-valued systems is developed and the biHamiltonian structures for several examples are found.

In the bounds of a theoretical scheme treating consistently gravitational interaction as dynamical (gauge) field in flat space-time, an expression was obtained for the density of energy-momentum-tension of gravitational field in vacuum around a collapsed object. A case was studied of an interacting static spherically-symmetric field of a collapsar in vacuum with taking into account of input of all the possible components (spin states of virtual gravitons) into the energy for the symmetric tensor of second rank?ik. The radius of the sphere filled by matter for the collapsar of massM may achieve values up toGM/c2.

In the bounds of the consistent dynamic interpretation of gravitation (gravidynamics) a gravitational field has been divided into two components: scalar and tensor, each one interacting with its source by the same coupling constant. Consequently, a spherically-symmetrical gravitational field in vacuum generated by a massive object influences test bodies as an algebraic sum of attraction and repulsion. Field energy in vacuum around the source is also a sum of energies of two components — purely tensor and scalar ones of gravitation. At distances from a gravitating object much greater than its gravitational radius, energies of each separate field component are equal to each other at the same point of space.

The dialanes [(dpp-Bian)Al–Al(dpp-Bian)] (1) and [(dpp-dad)Al(THF)–(THF)Al(dpp-dad)] (2) (dpp-Bian = 1,2-[(2,6-iPr2C6H3)NC]2C12H6, dpp-dad = [(2,6-iPr2C6H3)NC(CH3)]2) react with some isothiocyanates, isocyanates, and diphenylketene via [2 + 4] cycloaddition of the C═O or C═S bond across the C═C—N—Al fragment to afford complexes [L(X═C—Y)Al—Al(X═C—Y)L] with an intact Al–Al single bond (3, L = dpp-Bian, X = PhN, Y = O; 4, L = dpp-Bian, X = Ph2C, Y = O; 6, L = dpp-dad, X = BnN, Y = S; 7, L = dpp-dad, X = tBuN, Y = O; 8, L = dpp-dad, X = iPrN, Y = S; and 9, L = dpp-dad, X = CyN, Y = S). A mixed C═N and C═O mode cycloadduct, [(dpp-Bian)(TosN═C—O)Al—Al(TosN—C═O)(dpp-Bian)] 5, was obtained in the reaction of 1with tosylisocyanate. Heating the solution of 3resulted in a thermal transformation and a change of the cycloaddition mode from C═O to C═N to give the product [(dpp-Bian)(PhN—C═O)Al(O)Al(PhN—C═O)(dpp-Bian)] 10. The reduction of 7and 8with Na yielded the products [Na(THF)n]2[(dpp-dad–H)(X═C—Y)Al]2(12, X = iPrN, Y = S, n= 2 and 13, X = tBuN, Y = O, n= 3) in which one of the methyl groups of the backbone of the initial dpp-dad ligand was dehydrogenated. When 2was reacted with the bulky adamantyl isocyanate AdNCO, the C–C coupling of two substrates occurred to form 14[(dpp-dad)Al(O═C—NAd)2Al(dpp-dad)] in which the coupled dianionic oxamide ligand bridged two Al atoms in a μ,η4-N,O/N,O mode. Moreover, in the presence of 2.0 equiv of Na metal, precursor 2reacts with tBuNCS, p-TolylNCS, or Me3SiNCO, possibly through the reduced AlIintermediate, to yield the sulfur- or oxygen-bridged dimer [Na(solv)n]2[(dpp-dad)Al(μ-E)]2(15, E = S, solv = THF, n= 3 and 16, E = O, solv = DME, n= 2) upon C═S or C═O bond cleavage. Dialane 1reacts with dimethylsulfone to give a Lewis adduct [(dpp-Bian)(Me2SO2)Al]2(17), which releases dimethylsulfone upon heating. The diamagnetic compounds 3–10and 12–17were characterized by NMR and IR spectroscopy. The molecular structures of 3–17were established by single-crystal X-ray diffraction analysis. Electronic structures of the compounds and possible isomers have been examined by DFT calculations.

The compounds (II) and (III) are screened for their inhibitory activity towards acetylcholinesterase (AChE), butylcholinesterase (BChE), and carboxylesterase (CaE).