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The results of a laser—matter interaction experiment are presented in the paper. Low-density volume-structured material (cellulose triacetate) is used as a target in the experiments. Low-density materials are of interest for both fundamental and applied research. The information on how the parameters of the target and laser radiation influence the penetration of laser radiation through the generated plasma layer is generalized. The energy, spatial, spectral, and temporal characteristics of the plasma of low-density cellulose triacetate targets are analyzed. [ABSTRACT FROM AUTHOR]

Mass spectrometry with electrospray ionization (ESI-MS) was used for the first time to study the formation of supramolecular complexes of glycyrrhetic acid (GLA) with benzimidazole (BMZ) derivatives (9-diethylaminoethyl-2,3-dihydroimidazo[1,2-a]benzimidazole dihydrochloride). ESI-MS spectra showed peaks for non-covalent complexes of GLA with BMZ that contained from 3 to 7 GLA molecules and one BMZ molecule (3:1, 4:1, 5:1, 6:1, and 7:1). Peaks for non-covalent complexes corresponding to ions containing one or two GLA molecules and one BMZ molecule (1:1 and 2:1) were not observed. Increasing the GLA mole fraction in the samples increased the peak intensities of the GLA-BMZ complexes. GLA self-assembly and GLA complexation with BMZ occurred simultaneously and were competitive. [ABSTRACT FROM AUTHOR]

Production of density gradient aerogels with predetermined density steps or gradient is challenging, particularly when the experiments would demand a prescribed gradient in density along the axis of cylindrical shaped aerogel. In order to achieve this, it is vital to characterize and accurately measure the density gradient in order to 'design' synthetic routes to achieve the desired density gradient that can be used in plasma physics experiments using high-energy lasers. X-ray tomography was used for the characterization of these aerogels and it is demonstrated that it is the most reliable and quick method for characterization of gradient density aerogels. Divinyl benzene aerogels samples were synthesized by Lewis acid catalysis and samples were supercritically dried, characterized and their parameters measured to realize that the necessary properties were achieved. The change in density from solid density to 100 mg/cm is registered and the accuracy is evaluated. [ABSTRACT FROM AUTHOR]

The properties of microheterogeneous plasma produced by irradiation of a polymer aerogel target with an intense (10 W/cm) short (0.5 ps) 1.064-μm laser pulse were studied. It is found that, even at plasma densities exceeding the critical density, a small fraction of the incident laser radiation penetrates through the plasma in which the processes of density and temperature equalization still take place. The intensification (as compared to plasmas produced from denser foams and solid films) of transport processes in such plasma along and across the laser beam can be caused by the initial microheterogeneity of the solid target. The replacement of a small (10% by mass) part of the polymer with copper nanoparticles leads to a nearly twofold increase in the intensity of the plasma X-ray emission. [ABSTRACT FROM AUTHOR]

Self-association of caffeine has been investigated using mass spectrometry. It was found that associates are composed of caffeine trimers and hexamers. The possibility of complex formation of caffeine with triterpene glycosides 3- O-α- L-rhamnopyranosyl-(1→2)- O-α- L-arabinopyranoside of hederagenin and its 28- O-α- L-rhamnopyranosyl-(1→4)- O-β- D-glucopyranosil-(1→6)- O-β- D-glucopyranosil ester have been considered. Under the experimental conditions, inclusion compounds do not form and only self-associates of caffeine and glycosides are found. [ABSTRACT FROM AUTHOR]

Laser fusion for energy and hybride schemes with laser application are original and highly tempting because they are ecofriendly, with almost unlimited resources. Though quite challenging, even development stage is fruitful in hi-tech and provides vast fundamental knowledge. The present paper discusses important results concerning target fabrication detailing several finer points of view which may not appear obvious. The current status of and achievements in targets are provided and validation experiments are discussed. The prospects and the unexpected difficulties are presented. The comparable resources and cost (unlike sizes differing orders of magnitude) for the targets and for driver over the driver's life cycle scale prove there is no time to waste with target technology findings and validation experiments, especially in view of ignition shortly expected with National Ignition Facility. [ABSTRACT FROM AUTHOR]

Self-association of hederagenin 3- O- α-L-rhamnopyranosyl-(1→2)- O- α-L-arabinopyranoside ( α-hederin) and its 28- O- α-L-rhamnopyranosyl-(1→4)- O- β-D-glucopyranosyl-(1→6)- O- β-D-glucopyranosyl ether (hederacoside C) with cholesterol was studied using mass spectrometry (ESI MS). Possible complexation of the glycosides with cholesterol was examined. The ichtyotoxic activity of the glycosides and their mixtures with cholesterol to Barbus fefrozona was studied. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper the electrodeposition of Ga on Au(111) from 0.5molL−1 GaCl3 in the air- and water-stable ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide, [Py1,4]TFSA, has been investigated by in situ scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and cyclic voltammetry (CV). The CV shows two redox processes: the one at −0.3V vs. Pt is attributed to a Ga deposition on a Ga layer formed during an electroless deposition process at OCP and/or to the formation of a Au–Ga alloy; the other one at −0.9V is due to the bulk deposition of Ga. The XPS measurement reveals that there is an oxide layer on the top of the gallium electrodeposit due to exposure to air. In situ STM measurements show that the first layer of the Ga deposit consists of islands of 10–30nm in width and several nanometers in height surprisingly the result of an electroless deposition at the OCP. If the electrode potential is further reduced the bulk deposition of Ga sets in. [Copyright &y& Elsevier]

Abstract: The electroreduction of 0.5M TaF5 on Au(111) and on polycrystalline gold substrates was investigated at room temperature in the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide, [Py1,4]TFSA, by cyclic voltammetry, in situ scanning tunneling microscopy (STM) and electrochemical quartz crystal microbalance (EQCM). The electrochemical reduction of TaF5 in the employed ionic liquid occurs in several steps. The first redox process is attributed to the reduction of TaF5 to TaF3, which likely occurs in the solution, as EQCM indicates no mass change. The electrodeposition of tantalum occurs only in a very narrow potential window and is preceded by the formation of various non-stoichiometric tantalum subhalides. Attempts to deposit micrometer thick tantalum layers at room temperature fail, presumably because of kinetic reasons. [Copyright &y& Elsevier]

The chemisorption of Zr(acac)4 and the formation of nanoparticles of ZrO2 on the surface of silica were studied by IR spectroscopy, thermogravimetry, thermal and X-ray phase analysis. The composition was established and the hydrolytic and thermal properties of ≡SiOZr(acac)3 groups were investigated. [ABSTRACT FROM AUTHOR]

Realization of the "Law on Strengthening the School's Contact with Life and Further Development of the Public Education System in USSR," which stipulates the inclusion of the vocational training of pupils in the secondary education, requires the urgent solution of the problem of the interrelation of general, polytechnical and vocational education. [ABSTRACT FROM AUTHOR]

The electrochemical reduction mechanism of niobium was studied in the ionic liquid 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate ([BMP][OTf]) containing niobium halides (NbCl 5 and NbF 5). The influence of the electrolyte composition, temperature, and nature of the substrate were systematically investigated. In situ electrochemical techniques, such as cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical quartz crystal microbalance (EQCM) and rotating ring disc electrode (RRDE), were used, besides the ex situ characterization techniques scanning electron microscopy (SEM) and vibrational spectroscopy. The number of transferred electrons was estimated from the half width of the cathodic peaks in the DPV measurements. Furthermore, the product of the diffusion coefficient and the number of transferred electrons at the power of 3/2 were evaluated from RRDE measurements to be approx. 3 × 10−10 m2/s. Thicker and better adherent niobium-based deposits were obtained from NbCl 5 in [BMP][OTf] than from NbF 5 in [BMP][OTf]. EQCM measurements combined with DPV indicated the potential region where niobium-based deposits could be obtained as well as their stoichiometry. Vibrational spectroscopy reveals that NbF 5 and NbCl 5 interact differently with [BMP][OTf]. The spectra show that in the case of NbF 5 – [BMP][OTf] only niobium(V) anionic species [NbF 6 A]2- and [NbF 5 A]- (where A = [OTf]-) are formed, while in NbCl 5 – [BMP][OTf] both niobium(V) and niobium(IV) anionic species are present. At low NbCl 5 concentrations, [NbCl 4 A 2 ]2- and [NbCl 4 A 2 ]- are obtained, while at high NbCl 5 concentration, [NbCl 5 A]2- and [NbCl 5 A]- are found. The electrochemical niobium reduction mechanism depends on temperature and on the anionic species that are involved in the reduction process. In the case of NbCl 5 – [BMP][OTf], at high cathodic potentials the formation of subvalent Nb-clusters (possibly Nb 6 Cl 14) was observed. [ABSTRACT FROM AUTHOR]

The interaction of a high-power laser with a low-density foam target can in some instances result in a significant enhancement in x-ray generation relative to that when the same laser is incident upon a homogenous solid. In this paper, we present x-ray emission studies from foam targets where the density is varied from under-dense to over-dense. The targets are irradiated with the first harmonic of Nd:Glass laser. The laser intensity on the target was approximately 2x1014 W/cm2 with the pulse duration of 500 ps. Mass-matched cellulose triacetate foam targets with densities of 2 mg/cc, 4 mg/cc, 7 mg/cc, and 20 mg/cc were used. The areal density presented by the targets on the laser beam axis was held constant at 0.2 mg/cm2 by varying the target thickness in inverse proportion to the density. The x-ray yield in the spectral range (5-8 keV) and (4.5-16 keV) was found to be enhanced by approximately 2.3 times in foam targets with the density of 2 mg/cc (under-dense) compared with foam targets with the density of 20 mg/cc (over-dense). [ABSTRACT FROM AUTHOR]

Molecular complexes of glycyrrhizic acid (GA) and simvastatin (SV) were synthesized and studied for the first time using electrospray-ionization mass spectrometry (ESI-MS). Model complexes were synthesized in pure MeOH and its 25% aqueous solution. Complexation of GA and SV in the liquid phase was studied using ESI-MS and was confirmed using standard UV spectroscopy. Peaks for supramolecular GA-SV (1:1) complexes and a broad set of GA complexes with SV self-associates (GA-nSV, where n = 2, 3,...,5) were detected in mass spectra and indicated that competing processes were involved in synthesizing the GA-SV molecular complexes. The observed intensity changes of peaks for GA complexes with SV self-associates on going from MeOH to aqueous MeOH resulted from hydrophobic interactions that determined the effectiveness of SV self-association. [ABSTRACT FROM AUTHOR]

Model phenanthrene seco-alkaloids (seco-glaucine and seco-boldine) obtained in the medium of subcritical water (SBW) from plant aporphine alkaloids have been studied for the first time as antioxidants and inhibitors of acetylcholinesterase (AChE). Antioxidant activities (in vitro) of model aporphine and phenanthrene alkaloids: boldine, seco-boldine, glaucine and seco-glaucine (BD, s-BD, GL and s-GL) were studied in the reaction with a stable free radical DPPH (1,1-diphenyl-2-picrylhydrazyl). In vivo, antioxidant activity was determined in a bioluminescent test system using genetically modified E. coli strains. In the experiments in vitro (DPPH test) and in vivo (biotest), phenanthrene alkaloids s-GL and s-BD demonstrate the higher antioxidant activity than their aporphine precursors GL and BD. The anticholinesterase activity of alkaloids and their phenanthrene seco-isomers was studied (in vitro) using Ellman's method with minor modifications. The data on the inhibitory activity of the AChE enzyme with aporphine and phenanthrene alkaloids expressed as IC50 values obtained from dose–response curves demonstrate that the inhibitory activity for seco-boldine (IC50 = 0.21 mM) and seco-glaucine (IC50 = 0.04 mM) is higher than for the initial aporphine alkaloids boldine (IC50 = 0.29 mM) and glaucine (IC50 = 0.44 mM), respectively. Thus, it has been shown that phenanthrene alkaloids obtained in SBW exhibit the higher antioxidant activity and the better inhibitory AChE activity than their aporphine precursors. [ABSTRACT FROM AUTHOR]

Molecular complexation of streptocid (sulfanylamide) with 3- O-α-L-rhamnopyranosyl-(1 → 2)- O-α-L-arabinopyranoside of hederagenin (α-hederin) and its 28- O-α-L-rhamnopyranosyl -(1 → 4)- O-β-D-glucopyranosyl-(1 → 6)- O-β-D-glucopyranosyl ester (hedera saponin C) has been studied with electrospray ionization mass spectrometry for the first time. It was established that α-hederin forms a 1: 1 complex with streptocid. Hedera saponin C complexes with streptocid with the molar ratio 1: 1, 2: 1, and 2: 2 were more stable. Conclusions were drawn about the influence of the glycosides and streptocid structure on complexation. [ABSTRACT FROM AUTHOR]

Electrospray-ionization mass spectrometry (ESI-MS) was used to investigate for the first time the molecular complexation of L-phenylalanine with hederagenin 3-O- α- L-rhamnopyranosyl-(1 → 2)-O- α- L-arabinopyranoside ( α-hederin) and its 28-O- α- L-rhamnopyranosyl-(1 → 4)-O-β- D-glucopyranosyl-(1 → 6)-O-β- D-glucopyranosyl ester (hederasaponin C). The glycoside/ L-phenylalanine complexes with a 1:1 molar ratio turned out to be most stable. The structures of the glycosides and L-phenylalanine have been concluded to have an impact on the complexation process. [ABSTRACT FROM AUTHOR]

For the first time, the molecular complexation of adenine and guanine with hederagenin 3- O-α- L-rhamnopyranosyl-(1 2)- O-α- L-arabinopyranoside (α-hederin) and its 28- O-α- L-rhamnopyranosyl-(1→4)- O-β- D-glucopyranosyl-(1→6)- O-β- D-glucopyranosyl ester (hederasaponin C) was investigated using the method of electrospray ionization mass spectrometry. Guanine forms more diversely composed complexes than adenine. [ABSTRACT FROM AUTHOR]

Abstract: In the present study macroporous aluminium electrodes were made by template assisted electrodeposition from ionic liquids. Polystyrene (PS) spheres (diameter 600nm) were applied onto polished copper electrodes by immersion into an alcoholic suspension containing PS spheres. Al was deposited from the chloroaluminate ionic liquid [EMIm]Cl/AlCl3 (40/60mol.%) on this substrate. After chemical dissolution of the PS spheres a macroporous aluminium electrode was obtained which served as a host material for Li deposition from ionic liquids. Lithium deposition in this matrix is reversible showing certain activation with an increasing number of cycles. After 10 cycles of Li deposition/dissolution the macroporous structure is still visible. [Copyright &y& Elsevier]

Molecular complexation of paracetamol with hederagenin 3-O-α-L-rhamnopyranosyl-(1 → 2)-O-α-L-arabinopyranoside (α-hederin) and its 28-O-α-L-rhamnopyranosyl-(1 → 4)-O-β-D-glucopyranosyl-(1 → 6)-O-β-Dglucopyranosyl ether (hederasaponin C) was investigated for the first time using electrospray-ionization mass spectrometry (ESI-MS). The glycosides form complexes with paracetamol in a 1:1 molar ratio. The hederasaponin C complex is more stable. The structures of the glycosides and paracetamol are concluded to have an impact on the complexation process. [ABSTRACT FROM AUTHOR]

The results obtained by experimentally and theoretically studying the yield of the promising nuclear-fusion reaction B() initiated by powerful picosecond laser radiation of intensity W/cm are presented. A new procedure that relies on a simultaneous detection of the yield of alpha particles and the neutron yield in the reference reaction B C and which permits reaching a high precision of measurements is employed. The measured alpha-particle yield per pulse in the reaction B() is 10 particles in 4 sr at the above laser-pulse parameters. The results of a numerical particle-in-cell (PIC) simulation of the nuclear-fusion reaction B() proceeding in a solid-state boron target are presented. These results on the alpha-particle yield per pulse in the reaction B() agree fairly well with experimental results. [ABSTRACT FROM AUTHOR]

The time-of-flight technique coupled with semiconductor detectors is a powerful instrument to provide real-time characterization of ions accelerated because of laser–matter interactions. Nevertheless, the presence of strong electromagnetic pulses (EMPs) generated during the interactions can severely hinder its employment. For this reason, the diagnostic system must be designed to have high EMP shielding. Here we present a new advanced prototype of detector, developed at ENEA-Centro Ricerche Frascati (Italy), with a large-area (15 mm × 15 mm) polycrystalline diamond sensor having 150 μm thickness. The tailored detector design and testing ensure high sensitivity and, thanks to the fast temporal response, high-energy resolution of the reconstructed ion spectrum. The detector was offline calibrated and then successfully tested during an experimental campaign carried out at the PHELIX laser facility ( ${E}_L\sim$ 100 J, ${\tau}_L = 750$ fs, ${I}_L\sim \left(1{-}2.5\right)\times {10}^{19}$ W/cm2) at GSI (Germany). The high rejection to EMP fields was demonstrated and suitable calibrated spectra of the accelerated protons were obtained. [ABSTRACT FROM AUTHOR]

Large-amplitude electromagnetic radiofrequency fields are created by the charge-separation induced in interactions of high-intensity, short-pulse lasers with solid targets and have intensity that decreases with the distance from the target. Alternatively, it was experimentally proved very recently that charged particles emitted by petawatt laser–target interactions can be deposited on a capacitor-collector structure, far away from the target, and lead to the rapid (nanosecond-scale) generation of large quasi-static electric fields ($\mathrm{MV}/\mathrm{m}$), over wide regions. We demonstrate here the generation of both these fields in experiments at the PHELIX laser facility, with approximately $20\;\mathrm{J}$ energy and approximately ${10}^{19}\;\mathrm{W}/\mathrm{c}{\mathrm{m}}^2$ intensity, for picoseconds laser pulses, interacting with pre-ionized polymer foams of near critical density. Quasi-static fields, up to tens of kV/m, were here observed at distances larger than $1\;\mathrm{m}$ from the target, with results much higher than the radiofrequency component. This is of primary importance for inertial-confinement fusion and laser–plasma acceleration and also for promising applications in different scenarios. [ABSTRACT FROM AUTHOR]

We report on enhanced laser driven electron beam generation in the multi MeV energy range that promises a tremendous increase of the diagnostic potential of high energy sub-PW and PW-class laser systems. In the experiment, an intense sub-picosecond laser pulse of ∼1019 Wcm−2 intensity propagates through a plasma of near critical electron density (NCD) and drives the direct laser acceleration (DLA) of plasma electrons. Low-density polymer foams were used for the production of hydrodynamically stable long-scale NCD-plasmas. Measurements show that relativistic electrons generated in the DLA-process propagate within a half angle of 2 ± 1° to the laser axis. Inside this divergence cone, an effective electron temperature of 10–13 MeV and a maximum of the electron energy of 100 MeV were reached. The high laser energy conversion efficiency into electrons with energies above 2 MeV achieved 23% with a total charge approaching 1 μC. For application purposes, we used the nuclear activation method to characterize the MeV bremsstrahlung spectrum produced in the interaction of the high-current relativistic electrons with high-Z samples and measured top yields of gamma-driven nuclear reactions. The optimization of the high-Z target geometry predicts an ultra-high MeV photon number of ∼1012 per shot at moderate relativistic laser intensity of 1019 Wcm−2. A good agreement between the experimental data and the results of the 3D-PIC and GEANT4-simulations was demonstrated. [ABSTRACT FROM AUTHOR]

The results of experimental investigations devoted to initiating the promising nuclear fusion reaction B in picosecond laser plasmas at a laser-radiation intensity of W/cm are presented. A new tool for determining the absolute yield of alpha particles in the reaction B on the basis of simultaneously measuring the number of neutrons in the reference nuclear reaction B C is proposed. At the above values of the laser-pulse parameters, the application of this new procedure to estimating the total number of alpha particles per pulse from the reaction B leads to a value of 10 particles within a solid angle of 4 sr. The results presented here differ substantially from the data obtained in measuring the single-channel yield of alpha particles. [ABSTRACT FROM AUTHOR]

The formation of self-associates of glycyrrhetinic acid (GLA), an aglycone of glycyrrhizic acid (GA), has been studied by electrospray ionization mass spectrometry. It has been shown for the first time that, analogously to triterpene saponins having free carboxyl groups, GLA stereoisomers can form self-associates. The capacity of GLA to form self-associates has been confirmed by the mass spectrometry data. It has been found that the ionization of GLA self-associates with the formation of an anion proceeds rather weakly. The ionization of GLA in the positive ion mode goes on effectively and makes it possible to record multidimensional structures of one to eight 18α-GLA molecules and from one to nine 18β-GLA molecules. The structure of GLA associates and their stability are demonstrated most comprehensively in positive ion mass spectra. As a whole, the sets and intensity of peaks for 18α- and 18β-GLA correlate well. The results of the mass spectrometry study show the capacity of 18α- and 18β-GLA stereoisomers to form self-associates, which indicates a high potentiality of GLA in providing noncovalent interactions during the formation of supramolecular complexes. Similarly to the saponins of licorice and ivy, GLA stereoisomers may form a potential basis for the synthesis of a new generation of noncovalent molecular complexes and novel highly effective medicinal substances owing to a possible improvement in bioaccessibility and possible synergistic effects. [ABSTRACT FROM AUTHOR]

Reducing the detrimental effect of the Rayleigh-Taylor (RT) instability on the target performance is a critical challenge. In this purpose, the use of targets coated with low density foams is a promising approach to reduce the laser imprint. This article presents results of ablative RT instability growth measurements, performed on the OMEGA laser facility in direct-drive for plastic foils coated with underdense foams. The laser beam smoothing is explained by the parametric instabilities developing in the foam and reducing the laser imprint on the plastic (CH) foil. The initial perturbation pre-imposed by the means of a specific phase plate was shown to be smoothed using different foam characteristics. Numerical simulations of the laser beam smoothing in the foam and of the RT growth are performed with a suite of paraxial electromagnetic and radiation hydrodynamic codes. They confirmed the foam smoothing effect in the experimental conditions. [ABSTRACT FROM AUTHOR]

A method for the ecologically pure extraction of chlorogenic acid from the marsh cinquefoil in a medium of subcritical water has been developed. The content of chlorogenic acid in extracts obtained in subcritical water and in an aqueous ethanol solution has been determined by HPLC. A high efficiency of extraction of chlorogenic acid from marsh cinquefoil tap roots in subcritical water without using expensive organic solvents has been demonstrated. [ABSTRACT FROM AUTHOR]

Self-association of simvastatin, which is widely used to treat coronary heart disease, was investigated using electrospray-ionization mass spectrometry. Formation of simvastatin self-associates in various solvents was demonstrated using mass spectrometry. Solvation effects were shown to play a special role in the formation of the self-associates. Self-associates containing from two to fi ve simvastatin molecules were detected in mass spectra of an aqueous MeOH (20%) solution of simvastatin. The formation of simvastatin self-associates could compete with the complexation of supramolecular structures during the synthesis of new generation drugs. [ABSTRACT FROM AUTHOR]

The formation of supramolecular complexes of glycyrrhetic acid (GLA) and levomycetin was detected and studied for the first time using electrospray-ionization mass spectrometry (ESI-MS). It was shown that the intermolecular complexes detected in the mass spectra were formed most effectively for a 1:1 host-guest ratio and less effectively for a 1:2 ratio. GLA aggregates (dimers and trimers) bound one or two levomycetin molecules and formed several singly and doubly charged cationic complexes. A comparison of the mass spectra of supramolecular complexes of glycyrrhizic acid (GA) and its aglycon (GLA) indicated that GLA self-aggregates and complexes with levomycetin formed more effectively than those of GA. [ABSTRACT FROM AUTHOR]

Plasma induced incoherence (PII) can strongly modify the growth rates of stimulated scattering instabilities. A special double-target design was used to quantify the effect of PII on stimulated Brillouin scattering (SBS). Successive shots using all or part of these targets led to the characterization of temporal and spatial incoherence of a laser pulse after propagation through a foam plasma and to the quantification of the reduction of SBS from the second target. Numerical simulations were used to identify the main physical mechanisms in play. [ABSTRACT FROM AUTHOR]

The molecular complexation of triterpene glycosides α-hederin (hederagenin 3- O-α-L-rhamnopyranosyl-(l → 2)- O-α-L-arabinopyranoside), hederasaponin C (hederagenin 3- O-α-L-rhamnopyranosyl-(l → 2)- O-α-L-arabinopyranosyl-28- O-α-L-rhamnopyranosyl-(l → 4)- O-β-D-glucopyranosyl-(l → 6)- O-β-D-glucopyranoside), and glycyram (monoammonium glycyrrhizinate) with sildenafil citrate was investigated for the first time using electrospray ionization mass spectroscopy. The glycosides form a complex in a 1: 1 molar ratio. The influence of the complex on Avena sativa seeds germination and its ichthyotoxicity against Poecilia reticulata were studied. [ABSTRACT FROM AUTHOR]

An experimental program was designed to study the most important issues of laser-plasma interaction physics in the context of the shock ignition scheme. In the new experiments presented in this Letter, a combination of kilojoule and short laser pulses was used to study the laser-plasma coupling at high laser intensities for a large range of electron densities and plasma profiles. We find that the backscatter is dominated by stimulated Brillouin scattering with stimulated Raman scattering staying at a limited level. This is in agreement with past experiments using long pulses but laser intensities limited to 2 × 1015 W/cm2, or short pulses with intensities up to 5 × 1016 W/cm2 as well as with 2D particle-in-cell simulations. [ABSTRACT FROM AUTHOR]

The molecular complexation of triterpene glycosides α-hederin (hederagenin 3- O-α-L-rhamnopyranosyl-(1 → 2)- O-α-L-arabinopyranoside) with hederasaponin C (hederagenin 3- O-α-L-rhamnopyranosyl-(1 → 2)- O-α-L-arabinopyranosyl-28- O-α-L-rhamnopyranosyl-(1 → 4)- O-β-D-glucopyranosyl-(1 → 6)- O-β-D-glucopyranoside) was investigated for the first time using the methods of IR- and electrospray ionization mass spectroscopy. The glycosides form a complex in the 1: 1 molar ratio. The influence of complex on Avena sativa seeds germination and its ichthyotoxicity against Poecilia reticulata were studied. [ABSTRACT FROM AUTHOR]

The electrodeposition of silicon was investigated from three different ionic liquids with the cation 1-butyl-1-methylpyrrolidinium ([Py]) and three different anions, namely, trifluoromethylsulfonate (TfO), bis(trifluoromethylsulfonyl)amide (TFSA) and tris(pentafluoroethyl)-trifluorophosphate (FAP) at room temperature and at 100 °C, respectively. The electrodeposition was performed on gold and on copper substrates. Cyclic voltammetry was used to evaluate the possible influence of anions on the deposition process. In situ STM studies were also carried out to examine the interfacial behaviour of the SiCl/[Py]TFSA and SiCl/[Py]FAP on Au(111) at room temperature. In situ STM measurements revealed that an underpotential deposition of Si in [Py]FAP occurred on Au (111) at ~ -0.5 V (vs. Fc/Fc). In comparison, only adsorption of ionic liquid and gold surface reconstruction was found to occur in the potential regime between -0.3 and −1.8 V (vs. Fc/Fc), respectively, in the case of [Py]TFSA. In situ STM investigations reveal an effect of the anion on the interfacial processes. In situ I/U tunnelling spectroscopy shows that the band gap of the electrodeposits is ~1.1 eV, indicating that semiconducting silicon has been electrodeposited. Potentiostatic electrolysis was performed to deposit Si from the employed electrolytes at room temperature and at 100 °C. The deposits were characterised using scanning electron microscopy and X-ray diffraction. Thin films of Si could be obtained from the employed ionic liquids and the quality of the deposits was significantly improved at 100 °C. [ABSTRACT FROM AUTHOR]

The mechanisms of laser imprint reduction on a surface of a planar foil performed using an underdense foam are presented. The consequences on the Rayleigh–Taylor instability growth at the ablation front when the foil is accelerated are studied. The analysis is based on numerical simulations using a chain of codes: the electromagnetic paraxial code PARAX provides the modifications of the intensity perturbation spectrum while the laser beam is crossing the foam. Two-dimensional axially symmetric simulations with the radiation hydrodynamic code CHIC describe the foam expansion and the foil dynamics. Finally, the perturbed flow calculations and the instability growth are investigated with the two-dimensional CHIC version in the planar geometry by using the initial and smoothed perturbation spectra. The dominant role of temporal laser smoothing during the time of foam crossing by the laser beam is demonstrated. Applications to the direct drive targets for inertial confinement fusion are discussed. [ABSTRACT FROM AUTHOR]

The propagation of an ionization wave through a subcritical foam is studied under inertial confinement fusion conditions. Independent measurements of the ionization wave velocity are compared with hydrodynamic simulations and analytical models. It is shown that simulations of a homogeneous material at equivalent density strongly overestimate the front velocity. The internal foam structure can be accounted for with a simple model of foam homogenization that allows improving agreement between experiment and calculations. [ABSTRACT FROM AUTHOR]

To investigate the complexation of L-tyrosine (Tyr) with hederagenin 3-O-α-L-rhamnopyranosyl-(1→2)-O-α-L- arabinopyranoside (α-hederin) and its 28-O-α-L-rhamnopyranosyl-(1 → 4)-O-β-D-glucopyranosyl-( 1→6)-O-β-D-glucopyranosyl ester (hederasaponin C); to study the effect of glycosides, Tyr, and their mixtures on Avena sativa L. seed germination. Methods. Electrospray ionization mass spectrometry. Results. Mass spectra of mixes of glycosides with Tyr have been received and interpreted. The comparative analysis of biological activity of individual glycosides and their complexes with Tyr and others aromatic amino acids has been performed. Conclusions. For the first time a composition of the complexes is established by mass spectrometry. The complex of β-hederin with Tyr has appeared most toxic. [ABSTRACT FROM AUTHOR]

The complexation of antibiotic levomycetin (chloroamphenicol) with triterpene glycoside α-hederin and hederasaponin C was investigated by electrospray ionization mass spectrometry. The glycosides form complexes with levomycetin in the molar ratio 1: 1. The molecular complex of α-hederin is more stable than the one of hederasaponin C because of the presence of a free carboxyl group in its aglycone fragment. The carboxyl group of hederasaponin C is involved into the formation of a glycosidic bond with the trisaccharide unit and is not available for complex formation. [ABSTRACT FROM AUTHOR]

Electrospray ionization mass spectrometry has been used to study the self-association of α-hederin and hederacoside C (from Hedera) glycosides. The complexation of glycosides with cholesterol has been considered. It has been revealed that α-hederin forms self-associates registered in ESI mass spectra, while no self-associates have been found for hederacoside C and cholesterol. Cholesterol produces molecular complex with α-hederin, while complex formation between cholesterol and bisdesmoside hederacoside has not been observed. [ABSTRACT FROM AUTHOR]

Abstract: Interaction of soft X-ray thermal radiation with polymer foam layers has been studied experimentally. Indirectly heated CHO-foams were used to create a plasma target for applications in combined heavy ion beam-laser experiments that are aimed at investigation of the heavy ion energy loss in ionized matter. In this work, we report experimental results on heating of low Z foams by means of the Planckian radiation generated in gold hohlraums. The experimental goal was to study the hohlraum radiation field, duration of the soft X-ray pulse, the conversion efficiency of the laser energy into soft X-rays, measurements of the absorption properties of foam layers and parameters of the foam targets heated by the Plankian radiation. [Copyright &y& Elsevier]