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Luminescence spectra of naphthalene and benzophenone doped with their monosubstituted derivatives at 4.2 K were studied. The multiplet structure of these spectra was analyzed using the symmetry properties of the free molecules and crystal structures. It was shown that fl uorescence and phosphorescence spectra of the studied objects had a doublet character.

Brazilian transnational corporations (TNCs) have increased foreign direct investment nearly every year since 2001. This paper assesses Brazilian TNCs’ transnationality index and the relationship with both objective and subjective foreign performance. An empirical study was conducted of 41 Brazilian TNCs’ international activities in 2008 and 2009. The results demonstrate that an increase in the degree of internationalization is associated with better foreign performance. This relationship is stronger for the objective performance dimension than the subjective dimension. Furthermore, UNCTAD’s transnationality index is more reliable in this context than an alternative construct that includes other internationalization measures.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 850-853, The goal of this work is to demonstrate that heterojunction ITO/Si based solar cells fabricated by non-vacuum spray pyrolysis technique for deposition of indium-tin-oxide (ITO) based layers, can be considered as a promising approach for the cost effective processing of ITO/n-type Si based solar cells. It is established that preparation of an intermediate layer between ITO and Si is a crucial step, which determines efficiencies of ITO/Si based solar cells. Two approaches for the formation of such buffer layer have been considered: (i) chemical etching, which results in a formation of a thin Si porous/ sponge-like ITO/Si interface layer and (ii) low- temperature (~450 C) anneals, which result in a formation of a thin SiOx layer at the ITO/Si interface. A set of analytical characterization methods (SEM, TEM, EELS, EDS) have been used for the analysis of individual ITO layers as well as ITO/Si interfaces. It is established that formation of an ultra-thin SiOx layer at the ITO/Si interface is the most promising route to fabricate heterojunction ITO/Si solar cells with the reasonable (above 14%) efficiencies at a low-cost. General technological trends, which lead to an improvement of the conversion efficiency of ITO/Si solar cells, as well as further steps for optimization and improvement of the low-cost processing routes for ITO/Si solar cells are discussed.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 1186-1189, Thin Cu2ZnSn(SxSe1-x)4 films with x = 1.0 and 0.85 were prepared by the spray pyrolysis method with subsequent annealing in the presence of elemental sulfur or selenium. The surface sensitive Raman measurements indicated a high crystalline quality of all samples and absence of secondary phases. Small amount of Cu2-xS secondary phase was detected from grazing incidence X-ray diffraction patterns (information depth of about 500 nm). The resistivity, (T), is governed by the Mott variable-range hopping conduction at high temperatures, when the mean hopping length Rh (T) exceeds the mean distance between the acceptors, RA, but is still smaller than the typical inter-grain distance, aig. However, with lowering the temperature the resistivity becomes dominated by inter-grain tunneling, provided that Rh (T) > aig. The analysis of the (T) function has yielded the values of the acceptor concentration and the localization radius, with the evidence that all the samples are characterized by a state far different from the metal-insulator transition. The radius of the mean size grain as well as values of aig were in addition determined.

The results on the optimization of the parameters of solar cells (SCs) with monofacial and bifacial sensitivity based on n+ITO-SiO2-n-n+Si structures with isotype junctions are described. The developed technique of the structurization of silicon wafer surfaces makes it possible to increase the efficiency of solar radiation conversion to electric energy by up to 15.8% for monofacial SCs and up to 20.9% for bifacial SCs.

In this work we realized a new kind of bifacial solar cell with two isotype junctions based on the semiconductor–insulator–semiconductor structure. These devices were fabricated on nSi Cz wafers; the front junction was realized depositing ITO using the spray pyrolysis technique. A back surface field region was obtained by a P-diffusion process at the rear contact. To better evaluate the effectiveness of the rear side, we compared the performances of the latter cell with monofacial one having the same front junction, but with an extended metal contact on the rear surface of the wafer. All the devices were characterized by IV light, IV dark and quantum yield. The best bifacial cell realized in our laboratory achieved the efficiency of 9.0% (front side illumination) and 3.6% (rear side illumination), while the efficiency for the best monofacial solar cell was 9.6%. © 2008 Elsevier B.V. All rights reserved.

The possibility of nanostructuring of surfaces of indium phosphide with hole conduction is confirmed. The technique of manufacturing and research of SnO2/InP heterostructures with a nanoporous surface at the interface is developed. It is shown that the investigated structure can form a basis for working out photovoltaic devices with an enlarged active surface.

Peculiarities of obtaining of tin oxide and titanium oxide layers and semiconductor structures on their basis are described. The X-ray diffraction data show that the SnO2 and TiO2 layers possess the tetragonal crystal structure (anatase modification for TiO2). The results of analysis of the elemental composition and impedance investigations of the fabricated structures in model chloride-sulfate solutions demonstrate that the oxide/SiO2/Si structures are obtained if Si substrates are used. In the case of InP substrates, the oxide layer at the interface is not detected and the corresponding structure is oxide/InP. The results of investigations of corrosion show that a substantial shift of the corrosion potential to the anode region is observed in the case of deposition of SnO2 and TiO2 oxide layers on Si and InP crystals and fabrication of corresponding semiconductor structures. This demonstrates the possibility of the use of these materials in photoelectrochemical applications.

The influence of thermal treatment in H2 on the parameters of In/nITO/pInP/Ag:Zn solar cells obtained by ITO layers pyrolithic pulverization have been investigated. TheITO/pInP heterostructures obtaining take place at the temperature of 4500 C. As a result of these investigations it was shown that the thermal treatment of In/nITO/pInP/Ag:Zn SC in H2 at 3500 C during 10min leads to the considerable improvement of their photoelectric parameters. The photoelectric parameters of the best solar cell received on InP wafers with concentration p=3∙1017cm-3 after the thermal treatment are Voc=0,626V, Isc=22,72mA/cm2 , FF=71%, Eff=10,09%.

The method of n+Si/nSi/SiO2 /n+ITO bifacial solar cells fabrication by pyrolitical spraying was elaborated. This structure contains only isotype junctions. The spectral sensitivity is situated in the 350–1200nm wavelength region and is independent on the illumination direction. The photoelectrical parameters of solar cells obtained on silicon wafer (4,5 Ohm.cm) are following: at frontal illumination Voc=0,425V, Isc=32,63mA/cm2 , FF=68,3%, Eff=9,47%; at rear illumination Voc=0,392V, Isc =13,20mA/cm2 , FF=69,3%, Eff=3,60%.

Cluster control has been explored with a number of platforms at Santa Clara University's Robotics Systems Laboratory, but has not been thoroughly explored for aerial robots. Building on the foundation of previous work by this lab, a team of students developed an aerial testbed at NASA Ames for Parrot's AR.Drone 1.0s. This setup was designed to accommodate two and three robot configurations, including both aerial and land-based robots. This publication discusses the testbed setup and presents some of the preliminary results achieved using this testbed.

31st European Photovoltaic Solar Energy Conference and Exhibition; 1358-1361, Spectral and time dependent surface photovoltage (SPV) measurements were performed on Cu2ZnSn(SxSe1-x)4 (CZTSSe) thin films prepared on ITO/glass substrates by spray pyrolysis at ambient atmosphere from aqueous solutions and subsequent selenization of Cu2ZnSnS4 (CZTS) layers. The morphology, stoichiometry and phases of the crystalline thin films were studied by electron microscopy, energy dispersive x-ray analysis and xray diffraction, respectively. The CZTSSe thin films show mostly the kesterite type CZTSSe phases and are slightly copper deficient. The Se/(S+Se) ratio amounted to about 0.27. The onset energies of SPV signals were observed at about 1.0 and 1.5 eV. The transition at 1.0 eV can be attributed to the SnSe secondary phase with an indirect band gap of 0.90 eV. The energy of 1.5 eV corresponds to the band gap of the CZTSSe with about 25 % of Se content. A slow relaxation process and a change of the sign set on at photon energies above 1.5 eV. Results are discussed in relation to the phase analysis.

The artist traces his work from its beginnings behind the Iron Curtain in 1967, when cybernetics became the driving force of his creative process, to the present day. Given the scarcity of information and the absence of access to Western experimental work in Romania, this step was the unlikely result of a purely personal train of thought. He went on to lecture and write extensively to promote cybernetics and explain his approach to art, which was highly unconventional in the context of the times. Two directions emerged and remain the focus of his work today: the S-Band, an interactive art machine, and the Meta-Phorm, a behavioral geometry articulated by cybernetic mechanisms.

The photoelectrochemical properties of semiconductor-electrolyte solar cells with carbon auxiliary electrode and colloidal aqueous solution of Na 2 SiO 3 have been investigated. Bulk n-type single crystalline and nanoporous GaAs material were used as semiconductor electrodes. Current-voltage characteristics under different illumination intensities and spectral distribution of the photosensitivity were studied. The photopotential was found to reach values as high as 0.46 V for bulk n-GaAs. The introduction of porosity in GaAs shifts the maximum of the spectral distribution of photosensitivity towards the longwavelength region and increases the short circuit current by a factor of two.

29th European Photovoltaic Solar Energy Conference and Exhibition; 1823-1825, The Cu2ZnSnS4 (CZTS) thin films were prepared by spray pyrolysis method at ambient pressure. Subsequent annealing of the CZTS layers in vapors of elemental selenium allowed to prepare the Cu2ZnSn(SxSe1-x)4 (CZTSSe) solid solutions. The energy dispersive X-ray analysis as well as Raman scattering investigation confirmed the formation of solid solution with an anion ratio Se/(S+Se) ≈ 0.33 after annealing in Se-atmosphere. Investigation of temperature dependence of resistivity yielded the activation character for both CZTS and CZTSSe samples in whole temperature range of 40 – 300 K. The Mott variable-range hopping conductivity was observed in a large temperature interval, and its analysis showed that the CZTS film is closer to metal-insulator transition than CZTSSe film. The glass/ITO/CdS/CZTSSe/Ag structures were prepared by using different deposition methods for different layers. Optical activity of the CZTSSe layer was demonstrated from the spectral distribution of photoconductivity of the obtained glass/ITO/CdS/CZTSSe/Ag structure.

29th European Photovoltaic Solar Energy Conference and Exhibition; 1801-1804, Cu2ZnSnS4 thin films were grown by the spray pyrolysis method and annealed in an evacuated ampoule in presence of elemental sulfur. Annealing led to a significant decrease of the conductivity (by more than three orders of magnitude at room temperature). Transport properties are governed by the Mott variable-range hopping conduction mechanism in the as-deposited film and by the inter-grain conduction in the annealed film. Photoconductivity data, including the persistent photoconductivity and the modulated surface photovoltage, are almost independent of the annealing process, implying a high concentration of defects in both samples. The increase of the signal intensity in photoconductivity measurements is attributed to surface conditioning effects caused by annealing.

29th European Photovoltaic Solar Energy Conference and Exhibition; 851-854, Si3N4-nanolayers were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized silicon nitride was used as a solid-state target. The deposition was carried out on a cold substrate of p-Si (100) with a resistivity of 2 Ohmcm. The film thicknesses were up to 20 nm with the height of the structural units of about 1-2 nm. Vibrations at frequencies of 288, 307 and 347 cm-1 in the spectrum of Raman scattering were detected, which correspond to the cubic modification of silicon nitride. The shape of the spectrum is characteristic for the nanocrystalline state. A heterostructure was obtained by the deposition of a Si3N4 nanolayer on the surface of p-Si wafer and a p-Si/n-Si3N4 nanolayer photovoltaic cell was fabricated. The barrier height at the Si/Si3N4 interface is 0.9-1.0 eV. The investigation of the electrical and photoelectric properties of such devices shows that the Si/Si3N4 interface has a metal-insulator-semiconductor surface barrier structure with an inversion layer formed in silicon. The spectral dependence of the Si/Si3N4 solar cells photosensitivity entirely corresponds to the respective characteristic of the Si solar cell. Load I-V characteristics of the elaborated photovoltaic devices demonstrate conversion efficiencies of 6.38%.

Background . Although mitral valve repair is considered the gold standard for treating mitral regurgitation, anterior leaflet prolapse may still remain a challenging problem. This challenge is even greater for posterior commissural prolapse. We have used papillary muscle repositioning to treat anterior leaflet prolapse and suggest it as an alternative technique for all other methods previously described. Methods . From 1989 to 1999 we performed 253 mitral valve repairs, among which 132 involved anterior leaflet prolapse. In this population there were two groups: group I (n = 92) treated with papillary muscle repositioning and group II (n = 40) treated with chordal shortening. There was no statistical difference between the two groups concerning age, functional class, and left ventricular function. Etiology was similar in both groups, a degenerative process being predominant. At echocardiography, regurgitation was graded 3.4/4 in both groups. There was no statistical difference concerning preoperative ejection fraction, end-systolic and end-diastolic left ventricular diameter. Results . There were one in-hospital death in group I and two deaths in group II not related to mitral valve repair. Mean follow up is 36.4 ± 29.2 months in group I and 70.5 ± 9.5 months in group II. No patient was lost to follow-up. Mean regurgitation at follow-up was 0.75 ± 0.67 in group I and 0.8 ± 0.8 in group II ( p = not significant). There was no statistical difference between the two groups concerning postoperative ejection fraction, end-systolic and end-diastolic left ventricular diameter. There was no late cardiac death in either group and there were no thromboembolic events. Actuarial survival rate is 98.9% and 96.3% in group I and 92.5% and 88.1% in group II at 3 and 8 years, respectively. Conclusions . Therefore, we conclude that papillary muscle repositioning is a safe technique that provides excellent results at mid-term follow-up and facilitates treatment of anterior leaflet prolapse.

Solar cells fabricated on the basis of semiconductor-insulator-semiconductor (SIS) structures have been obtained by deposition of transparent conductive ITO films onto silicon crystal substrates by the spray pyrolysis technique. Such structures may be considered as Schottky diodes with a thin insulating SiO2 layer at the interface formed during the ITO layer deposition. The examination of the current-voltage characteristics shows that, in n+ITO/SiO2/nSi structures, there are two mechanisms of the direct current flow: (i) tunneling-recombination at direct voltages less than 0.3V and (ii) over-barrier emission at voltages higher than 0.3V. In the first case, the direct current flow can be interpreted as multistep tunneling-recombination transitions of electrons from the silicon conduction band into the ITO conduction band with the number of steps being about 100. In the second case, the height of the potential barrier at the ITO-Si interface calculated from the I-V characteristics is about 0.65–0.68 eV.

Indium phosphide heterostructures and transparent conducting films of wide-gap oxides have previously been used in the development of highly efficient solar cells, making it possible to bring their efficiencies up to 18% [M, M. Koltun, Optics and Metrology of Solar Cells [in Russian], Nauka, Moscow (1985); V. M. Botnaryuk, L. S. Gagara, L. V. Gorchak et al., Geliotekhnika 23, 37 (1990); V. Botnariuc, L. Gagara, E. Negru et al., Solar Energy in Romania 2(1), 53 (1993)]. In the present paper results are reported from the first studies of the photoelectric properties, in linearly polarized light, of solar cells consisting of a heterojunction between single crystal indium phosphide and a mixed indium and tin oxide film (ITO film, E-g congruent to 3.6 eV [G. Check and A. Genis, Solid Stale Techol. 23(1), 102 (1980)]). (C) 1998 American Institute of Physics. [S1063-7842(98)01305-1].

The photoelectric properties of ITO/n-Si solar cells with ITO-side oblique incidence of linearly polarized light on the solar cells have been studied. Polarization photosensitivity and an increase in the relative quantum efficiency of photoconversion as a result of a decrease in reflection losses were found. The induced photopleochroism coefficient PI increases with the angle of incidence θ as PI∼θ2. The polarization photosensitivity of solar cells was studied as a function of the photon energy between the band gaps of the two contiguous materials. The results show that the solar cells studied can be used as selective polarimetric photosensors.

The paper deals with the analysis of literary data on the tumor cell heterogeneity. Phenotypic, genetic and epigenetic mechanisms of heterogeneity are considered. The heterogeneity of metastasis is considered too. The importance for the biology of populations of tumor cells and the sensitivity of tumors to therapeutic treatment are discussed.

An efficient and novel technique for computing timing vulnerability factors (TVF) in modern complex synchronous designs is introduced, where all key inputs are based on static timing data readily available in most design databases. The benefits of TVF for modern microprocessors and strategies to reduce TVF, and hence the overall soft error rate (SER), are presented.

The paper deals with the analysis of literary data on the tumor cell heterogeneity. Phenotypic, genetic and epigenetic mechanisms of heterogeneity are considered. The heterogeneity or metastasis is considered too. The importance for the biology of populations of tumor cells and the sensitivity of tumors to therapeutic treatment are discussed. Key Words: primary tumor, metastasis, heterogeneity, malignant phenotype, genetic instability, epigenetic factors.

Thin films of amorphous SiC were prepared by non reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solid state target. Deposition was carried out on a cold substrate of p Si 100 with a resistivity of 2 Ohm amp; 61655;cm. The Raman spectrum shows a dominant band at 982 cm 1, i.e. in the spectral region characteristic for SiC. The film thickness determined from atomic force microscopy measurements was about 8 40 nm, the height of the structural units of the film was 1 2 nm, while the linear dimensions were of the order of tens of nanometers. The amorphous nature of SiC grown on the Si substrate is confirmed by the presence of the diffraction rings which indicate the absence of the dominant orientation of the prepared films. A heterostructure consisting of a p type Si 100 and a layer of amorphous n type SiC was fabricated and studied. The investigation of its electrical and photoelectric properties shows that the entire space charge region is located in Si. This is in addition confirmed by the spectral dependence of the p Si n SiC photo sensitivity. The barrier height at the p Si n SiC interface estimated from dark I V characteristics is of the order of 0.9 1.0 eV. Load I V characteristics of p Si n SiC amorphous nanolayer solar cells demonstrate under standard AM1.5 illumination conditions a conversion efficiency of 7.22

Internationalization has long been discussed in the strategic management literature as a way of diversifying a business and creating value (Dunning, 2000; Johanson & Vahlne, 1977). Yet firms have different strategies in terms of entry mode (Kogut & Singh, 1988) and ownership (Hennart & Reddy, 1997). Some of them, depending on their industry and strategic objectives prefer to open commercial offices to support sales from the home country, whereas others avoid transportation costs by exporting parts of products and finalizing those in foreign markets. Some others see opportunities for the acquisition or opening of production plants to carry out all stages of the value chain in the country of destination (Dunning, 1980). Services providers usually have a support branch and displace its staff, whether in operations or direct contact with customers (Philippe & Leo, 2011).

28th European Photovoltaic Solar Energy Conference and Exhibition; 1317-1320, Thin films of amorphous SiC were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solid-state target. Deposition was carried out on a cold substrate of p-Si (100) with a resistivity of 2 Ohmcm. The Raman spectrum shows a dominant band at 982 cm-1, i.e. in the spectral region characteristic for SiC. The film thickness determined from atomic force microscopy measurements was about 8-40 nm, the height of the structural units of the film was 1-2 nm, while the linear dimensions were of the order of tens of nanometers. The amorphous nature of SiC grown on the Si substrate is confirmed by the presence of the diffraction rings which indicate the absence of the dominant orientation of the prepared films. A heterostructure consisting of a p-type Si (100) and a layer of amorphous n-type SiC was fabricated and studied. The investigation of its electrical and photoelectric properties shows that the entire space charge region is located in Si. This is in addition confirmed by the spectral dependence of the p-Si/n-SiC photo sensitivity. The barrier height at the p-Si/n-SiC interface estimated from dark I-V characteristics is of the order of 0.9-1.0 eV. Load IV characteristics of p-Si/n-SiC-amorphous-nanolayer solar cells demonstrate under standard AM1.5 illumination conditions a conversion efficiency of 7.22%.

28th European Photovoltaic Solar Energy Conference and Exhibition; 2449-2452, Thin Cu2ZnSnS4 films have been deposited by spray pyrolysis method in argon and ambient atmosphere, followed by annealing to improve the film quality. Temperature dependence of the resistivity,, is investigated before and after the annealing in the interval of T between ~ 10 – 300 K. The as-deposited films, as well as those annealed at low temperature, exhibit the Mott variable-range hopping (VRH) conduction. Analysis of the experimental (T) data has yielded microscopic relevant parameters of the layers. Annealing at highest temperatures determines domination of the inter-grain (IG) conductivity over the Mott VRH conduction mechanism. The grain sizes, estimated with the analysis of the IG conduction, are in a reasonable agreement with those obtained by scanning electron microscopy investigations.

Silicon p + n-insulator-ITO structures have been obtained by the deposition of a thin layer of In 2 O 3 :SnO 2 ((ITO) on the n-region of a silicon p-n junction by a spray method. The two-terminal structure shows S-shaped negative resistance I–V characteristics similar to long-base diodes, thyristors and other switching devices. The switching is controlled by optical illumination, but unlike other S-shaped devices, in our case the light switches the structure from high-resistance to the low-resistance state. A band diagram for the investigated structure has been proposed. This diagram allows one to explain the observed current switching as a result of double injection in the nSi region, which became difficult under illumination.