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Polyacenes among other polycyclic aromatic hydrocarbons (PAHs) were suggested to be abundant in the dense regions of the interstellar medium (ISM) and to be responsible for some of the diffuse interstellar bands (DIBs). The identification of DIB carriers requires the laboratory spectra of cold cations for comparison with astrophysical observations. We employed He-tagging spectroscopy to record the spectrum of tetracene cations. In contrast to previous measurements of other polyacene cations, we found very narrow absorption bands of tetracene +. This makes the detection of tetracene+ in the ISM much easier compared to other studied polyacene cations. The four absorption bands of tetracene+ that are the best suited for the detection in observational spectra appeared at 859, 850.9, 838.8, and 827.3 nm. We did not find any DIBs at these positions. However, the observational spectra in this region from ground-based telescopes are heavily contaminated with telluric absorption bands, which greatly complicates the detection of DIBs. Comparison with observations performed by space telescopes is expected to significantly increase the sensitivity of the detection of the DIBs that could potentially be assigned to tetracene+. [ABSTRACT FROM AUTHOR]

The electronic transition spectra of the indene molecular cation (In + , C 9 H 8 + ) in the 550–580 nm region has been measured in the gas phase in direct absorption. The spectra were experimentally recorded using sensitive cavity ring-down spectroscopy in a supersonically expanding planar plasma. Two lifetime-broadened vibronic bands are assigned to the 2 A ′ ′ - X 2 A ′ ′ electronic transition system of In + . A set of indicative spectroscopic parameters have been obtained from a band contour analysis of the 0 0 0 band in combination with supporting ab-initio calculations. The inferred Lorentz line width of 4.0 ± 0.5 cm − 1 indicates an upper state lifetime of 1.2 ± 0.1 ps . The laboratory data are compared to the diffuse interstellar bands (DIBs), and no matches can be found. Upper limits for In + column densities in the diffuse interstellar medium have also been estimated from six sightline spectra. [ABSTRACT FROM AUTHOR]

The electronic transition spectra of the indene molecular cation (In + , C 9 H 8 + ) in the 550–580 nm region has been measured in the gas phase in direct absorption. The spectra were experimentally recorded using sensitive cavity ring-down spectroscopy in a supersonically expanding planar plasma. Two lifetime-broadened vibronic bands are assigned to the 2 A ′ ′ - X 2 A ′ ′ electronic transition system of In + . A set of indicative spectroscopic parameters have been obtained from a band contour analysis of the 0 0 0 band in combination with supporting ab-initio calculations. The inferred Lorentz line width of 4.0 ± 0.5 cm − 1 indicates an upper state lifetime of 1.2 ± 0.1 ps . The laboratory data are compared to the diffuse interstellar bands (DIBs), and no matches can be found. Upper limits for In + column densities in the diffuse interstellar medium have also been estimated from six sightline spectra. [ABSTRACT FROM AUTHOR]

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Highlights • Verification of plasmonic behavior in GZO film (∼150 nm). • Checking on the sustainability of such plasmonic behavior in ultrathin GZO (∼5 nm). • Investigation of plasmonic feature at the heterojunction. • Band offset studies at the plasmon-enhanced-GZO/CIGSe heterojunction. • J-V analysis at the junction to verify the linear behavior and resistivity estimation. Abstract Recently, realization of ultrathin solar cells is the area of interest of researchers in the domain of cost-effective photovoltaics. This study demonstrates a novel way of generation of plasmonic features in transparent conducting oxide material in the form of Ga-doped ZnO (GZO) thin films to compensate for the loss of optical absorption due to reduced absorber thickness. Through an extensive analysis of photoelectron spectroscopy, spectroscopic ellipsometry, and field emission scanning electron microscope measurements the evaluation of plasmonic features and correlation of them with various metallic and metal-oxide nanoclusters inside GZO thin film and GZO/CIGSe heterojunction interface are carried out. Moreover, we have thoroughly analyzed the applicability of GZO plasmon enhanced thin film as a backscattering layer based on (a) verification of plasmonic behavior in GZO film (∼150 nm), (b) checking on the sustainability of such plasmonic behavior in ultrathin GZO (∼5 nm) layer, (c) investigation of plasmonic feature at the heterojunction, (d) band offset studies at the plasmon-enhanced-GZO/CIGSe heterojunction, and (e) investigating the electrical performance of the junction to verify the linear behavior and resistivity calculation of the heterojunction. [ABSTRACT FROM AUTHOR]

Abstract Cu 2 ZnSn(S,Se) 4 (CZTSSe) is an interesting absorber material for thin film solar cells. However, one of the key challenges for the kesterite-based solar cells is to improve the open-circuit voltage (V oc) deficit, which is resultant of recombination at the interface of buffer/absorber. In this work, Cd-free n -type buffer layers with two different Mg-doped ZnO layers (Mg 0.26 Zn 0.74 O, Mg 0.30 Zn 0.70 O) have been examined using ultraviolet photoelectron spectroscopy. The most important electronic properties which are essential for the band offset study, ie. fermi level location, valence and conduction band offsets at the interface in the CZTSSe substrate, have been determined. The conduction band offset values for Mg 0.26 Zn 0.74 O, Mg 0.30 Zn 0.70 O buffer layers has been calculated experimentally. We have also established the correlation between device parameters and performances for dual ion beam sputtered ZnO buffer/CZTSSe-based heterojunction solar cells as a function of conduction band offset and the energy distribution of interface defects, to gain deeper understanding about the V oc -deficit behavior from a high recombination rate at the buffer/kesterite interface using simulation study. From the simulation study, the values of the solar cell efficiency with Mg 0.26 Zn 0.74 O and Mg 0.30 Zn 0.70 O buffer layers are 10.18 and 10.25%, respectively, which are higher in comparison to those obtained by using conventional CdS buffer layer. Highlights • The band gap of 3.90 and 3.94 eV for Mg.26 Zn.74 O, Mg.30 Zn.70 O respectively using spectroscopic ellipsometry measurement. • The conduction band offset of 0.29 and 0.34 eV for Mg.26 Zn.74 O, Mg.30 Zn.70 O buffer layers have been obtained respectively. • The relationship between device parameters and performances for (Zn,Mg)O/CZTSSe-based solar cells has been established. • Solar cells with buffer layer of Mg.26 Zn.74 O and Mg.30 Zn.70 O has achieved efficiency of 10.18% and 10.25% respectively. [ABSTRACT FROM AUTHOR]

Abstract: Observations of dust‐infused baroclinic storm (DIBS) clouds (Fromm et al., 2016, https://doi.org/10.1002/2016GL071801) have revealed Saharan and Asian storm systems with mineral dust mixed with overrunning cirrus shield clouds at altitudes of 8–10 km. The unique characteristics observed in these clouds, including intense Cloud‐Aerosol LIdar with Orthogonal Polarization lidar backscatter and large daytime 3.9‐ to 11‐μm brightness temperature differences (indicating relatively small ice crystals), have prompted this modeling study to determine the mineral dust pathway and dynamics, if any, through an observed DIBS. We use the Advanced Weather Research and Forecasting Model with the chemistry model (WRF‐Chem) and constrained with the WRF data assimilation system (WRF‐DA) to conduct a reanalysis of an East Asian DIBS from 6 to 11 April 2010. Desert dust emission via the Global Ozone Chemistry Aerosol Radiation and Transport dust emission scheme (Ginoux et al., 2001, https://doi.org/10.1029/2000JD000053) and transport from both the Taklimakan and Gobi deserts is simulated within WRF‐Chem with the Model for Simulating Aerosol Interactions and Chemistry aerosol treatment (Zaveri et al., 2008, https://doi.org/10.1029/2007JD008782). In‐line air mass trajectories were used to source and trace dust transport from the storm spin‐up through dissipation 4 days later. Results show rapid dust transport from the Gobi desert to cirrus cloud tops via the warm conveyor belt mechanism, with the dust mixed throughout the cloud at altitudes from 5 to 10 km. Results are verified by good qualitative agreement with Cloud‐Aerosol LIdar with Orthogonal Polarization observations at several different moments in the DIBS cycle, including an elevated layer of dust that remains after storm cloud dissipation. These results confirm the potential for routine and significant dust‐cloud processing in DIBS cases, affecting both cloud properties and identifying a previously unidentified pathway for long‐range transport of dust. [ABSTRACT FROM AUTHOR]

This work aims to benefit from low quality fruits (of Saidy, Tamr and Manthor dates) by the production of enzymatically treated syrup with high quality value. From the chemical analysis, the total and reducing sugars were the predominate components in all studied date fruits varied from 50.5 to 81.8% and from 40.5 to 57.7% dry weight basis (dwb), respectively. The total acidity (as malic acid) of the studied date fruits ranged from 0.14 to 0.22%. The effect of different concentrations of pectinase enzyme, 0.5-2.0 % on the efficiency of date juice extraction process and physico-chemical proprieties of the obtained date syrup were studied. The enzyme treated date juices recorded the lowest values of viscosity, turbidity and color ( as absorbance at 520 nm), with the highest values of clarity compared with that of the untreated (control) samples. The results indicated that using 1% concentration of pectinase for 60 min at 50 °C gave a good result in terms of clarity, color and turbidity, but the recovery of total soluble solids was the highest after 90 min incubation time. The color values (as optical density at 420nm) of the enzyme-treated date syrups, Saidy, Tamr and Manthorranged from 0.499 to 0.574 compared with that of untreated date syrups which varied from 1.069 to 1.495. The treated Saidy date syrup had the highest clarity value followed by Tamr and Manthor syrups. From the obtained results it can be concluded that the enzymatic treatments could be used to produce date syrup (Dibs) with good properties and high quality from second grade date fruits. [ABSTRACT FROM AUTHOR]

Sb-doped p-Mg0.1Zn0.9O/ n -Si-based heterojunction ultraviolet photodetectors were fabricated using dual ion beam sputtering. Current–Voltage measurements showed good rectifying behavior in fabricated devices with rectifying ratio as high as 251.35 at ± 4 V. The detectors exhibited good ultraviolet spectral response having peak responsivity of 0.025 A/W (at 310 nm) and 0.32 A/W (at 320 nm) at −30 V. The values of peak responsivity and external quantum efficiency increased from 1.7 mA/W and 0.75% (at 0 V) to 0.32 A/W and 134.26% (at −30 V), respectively. The value of detectivity of heterojunction devices was calculated to be 3.65 \times 10^11 cm $\cdot $ Hz ^{\mathrm {1/2}} \cdot \text{W}^{\mathrm {-1}} at −5 V. [ABSTRACT FROM PUBLISHER]

Electrical Bioimpedance Spectroscopy (EIS) is a technique used to assess passive electrical properties of biological materials. EIS detects physiological and pathological conditions in animal tissues. Recently, the introduction of broadband excitation signals has reduced the measuring time for application techniques such as Electrical Bioimpedance Myography. Therefore, this work is aimed at proposing a prototype by using discrete interval binary sequences (DIBS), which is based on a system that holds a current source, impedance acquisition system, microcontroller and graphical user interface. Measurements between 5 Ω to 5 kΩ had impedance acquisition and phase angle errors of aproximately 2% and were lower than 3 degrees, respectively. Based on a proposed circuit, bioimpedance of the chest muscle (Pectoralis Major) was measured during isotonic exercise (push-up). As a result, our analyses have detected tiredness and fatigue. We have explored and proposed new parameters which assess such conditions, as both the maximum magnitude and tiredness coefficient. These parameters decrease exponentially with consecutive push-ups and were convergent in the majority of the sixteen days of measurement.

Blue multiple quantum well light-emitting diodes comprising of p-ZnO/(Cd 0.12 Zn 0.88 O/ZnO) multiple quantum wells/n-ZnO were grown on n-Si substrates using dual ion-beam sputtering deposition technique. X-ray diffraction of individual thin films revealed growth preferentially in c -axis direction perpendicular to the substrate. Photoluminescence studies indicated blue emission ~ 440 nm from CdZnO and UV emission ~384 nm arising from ZnO thin films. The LED showed a rectifying current–voltage behavior with a turn-on voltage of ~4.69 V at room temperature. It emanated a room-temperature electroluminescence peak centered at 442 nm, along with shoulder peak at 380 nm in ultra-violet region associated with the recombination in ZnO layers of structure. It was found that with the increase in injection current the blue EL intensity increased and UV emission decreased, leading to improvement in successful radiative recombination in quantum wells. The results indicate prospects of fabrication of ZnO-based blue multiple quantum well LEDs. [ABSTRACT FROM AUTHOR]

A systematic growth optimization of Cu 2 ZnSn(S, Se) 4 (CZTSSe) thin films by dual ion beam sputtering system from a single CZTSSe target is presented. It is observed that the ratio of Cu/(Zn + Sn) varies from 0.86 to 1.5 and that of (S + Se)/metal varies between 0.62 and 0.97 when substrate temperature (T sub ) is increased from 100 to 500 °C. The crystal structure of all CZTSSe films are identified to be preferentially (1 1 2)-oriented, polycrystalline in nature, and without the existence of secondary phases such as Cu 2 (S, Se) or Zn(S, Se). The full-width at half-maximum of (1 1 2) diffraction peak is the minimum with a value of 0.12° and the maximum crystallite size 75.11 nm for CZTSSe grown at 300 °C. Morphological investigation reveals the achievement of the largest grain size at T sub = 300 °C. The band gap of CZTSSe thin films at room temperature, as determined by spectroscopic ellipsometry, varies from 1.23 to 1.70 eV, depending on T sub . The optical absorption coefficient of all CZTSSe thin films is >10 4 cm −1 . [ABSTRACT FROM AUTHOR]

The electronic spectroscopy of various polycyclic aromatic hydrocarbon (PAH) molecules has been studied in the laboratory at low temperatures using both molecular beam and matrix isolation spectroscopy techniques. While molecular beam spectra can be readily compared to astronomical observations, the band positions measured in Ne and Ar matrices are extrapolated to obtain rather good estimates for the same transitions in the gas phase. Absolute absorption cross sections are determined for gas-phase and matrix spectra by comparing them with calibrated solution spectra. All laboratory results are analyzed and discussed in view of the role that PAHs can play as carriers of the diffuse interstellar bands (DIBs). Our studies suggest that regular neutral PAHs are not responsible for any of the known strong DIBs. [ABSTRACT FROM PUBLISHER]

Abstract: This study was conducted to select the best method of extraction. Different methods have been used to extract and concentrate the date syrup “Dibs”. Minced date flesh of Saidy variety was extracted twice using minced flesh at a water rate of 1:2 at 70°C for 30min using microwave, rotary evaporator and water bath and concentrated in a rotary evaporator and microwave. Apparently, use of microwave method for extraction and concentration of date syrup had a significant (p ⩾0.05) difference higher in the content of moisture, protein, total sugars, dietary fiber, total phenolics, hydroxymethylfurfural and ash, but it had no significant (p <0.05) difference in insoluble solids and fat content. The organoleptic evaluation of zabady and biogarde prepared with dibs are correlated with the chemical characteristics and microbiological tests. Results could be concluded that the caloric values of fermented milk products with 2% Dibs attained the highest values, actually 65.62 and 64.78KCal/100g for zabady and biogarde respectively. Total solids, S.N., T.A. and ash contents were gradually increased during storage periods. Also, zabady and biogarde with 2% dibs were found to be rich in all essential amino acids excluding lysine, histidine, threonine, and leucine+isoleucine. [Copyright &y& Elsevier]

In this paper we have shown the feasibility of ion beam assisted deposition to produce iron-nickel nitride thin films of various compositions. We have carried out their compositional and structural characterization by means of Rutherford backscattering spectroscopy (RBS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and integral conversion electron Mössbauer spectroscopy (ICEMS). The results have shown that Ni is incorporated within the films and that the temperature of the substrate has a large influence both in the phase composition obtained as well as in the degree of crystallinity of the thin films produced. [ABSTRACT FROM AUTHOR]

We present for the first time the UV/Vis spectrum of the neutral and ionized fullerene C84 isolated in a neon matrix at low temperature. After ionization with high energy (10.2 eV) UV photons, we are able to identify a new spectroscopic absorption band at 718.2 nm that we tentatively attribute to the C84+ ion. We compare the optical spectrum to the diffuse interstellar absorption bands (DIBs) and find eight possible DIBs that fall within the expected shift induced by the solid matrix (± 5 nm) of the assigned C84+ absorption band at 713.6, 713.8, 715.4, 716.1, 718.0, 722.3, 722.4, and 722.8 nm. The astronomical C84+ column density that is required to account for the observed strength of these DIBs is calculated assuming the oscillator strength of the C84+ transition obtained from the laboratory spectrum (f = 0.004). We find that 0.08% and 0.06% of the cosmic carbon abundance would be required to reproduce the 713.6 and 715.4 nm DIB, respectively. A ratio of cosmic C84+ to C60+ of ∼7% or ∼5% is derived based on the assignment of C84+ to the weakest DIBs at 713.6 or 715.4 nm, respectively. Both ratios are in good agreement with the C84+ to C60+ ratio measured in the laboratory under various experimental conditions. [ABSTRACT FROM AUTHOR]

Abstract: The electronic spectroscopy of polycyclic aromatic hydrocarbons (PAHs) is of particular interest for astrophysicists since these molecules are suggested as possible carriers of the diffuse interstellar bands. Here we report on our study of the S1←S0 transition of 2,3-benzofluorene (or benzo[b]fluorene) in the gas phase and in He droplets using cavity ring-down spectroscopy in a supersonic jet expansion and molecular beam depletion spectroscopy, respectively. The same techniques were also employed to identify the PAHs contained in the carbonaceous powder which was produced by CO2 laser pyrolysis of a mixture of ethylene and benzene vapor. Phenanthrene and anthracene were unambiguously confirmed as components of the as-synthesized soot. [Copyright &y& Elsevier]

The stoichiometry, structure and mechanical properties of ion beam sputtered TiCxNy thin films have been studied as a function of the assistance conditions. Tuning the ratio between the current density of assisting N2+ ions and the target sputtering rate allows us to achieve films with stoichiometries in the range of 0.6>x>0.25, keeping x+y&ap;1. The surface topography is also sensitive to the assisting conditions where the RMS roughness is an increasing parameter as the ion beam bombardment increases. In terms of the Ar+ ion beam assistance, the films undergo a significant amorphisation and a steep increase in lattice strain as the current density and energy of the impinging ions are increased. The observed changes are discussed in terms of the energy transfer of the bombarding Ar+ ions to the layers below the surface of the growing films, leading to vacancies and defects and to a sharp decrease in film crystallinity. [Copyright &y& Elsevier]

Comets provide a very different but well understood environment in which to search for DIBs. Observations of occultations by cometary comae have not detected DIBs, but none were very near the nucleus, where the column density of dust is highest. We report here unidentified emission bands, centered at λ4430, very near the nucleus of comet Hyakutake. These may be vaporized forms of grain carriers or fragments of large-molecule carriers. At least two different species appear to be present based on two different spatial distributions. [ABSTRACT FROM PUBLISHER]

Electrical Bioimpedance Spectroscopy (EIS) is a technique used to assess passive electrical properties of biological materials. EIS detects physiological and pathological conditions in animal tissues. Recently, the introduction of broadband excitation signals has reduced the measuring time for application techniques such as Electrical Bioimpedance Myography. Therefore, this work is aimed at proposing a prototype by using discrete interval binary sequences (DIBS), which is based on a system that holds a current source, impedance acquisition system, microcontroller and graphical user interface. Measurements between 5 Ω to 5 kΩ had impedance acquisition and phase angle errors of aproximately 2% and were lower than 3 degrees, respectively. Based on a proposed circuit, bioimpedance of the chest muscle (Pectoralis Major) was measured during isotonic exercise (push-up). As a result, our analyses have detected tiredness and fatigue. We have explored and proposed new parameters which assess such conditions, as both the maximum magnitude and tiredness coefficient. These parameters decrease exponentially with consecutive push-ups and were convergent in the majority of the sixteen days of measurement. [ABSTRACT FROM AUTHOR]

The use of the high free-electron concentration in heavily doped semiconductor enables the realization of plasmons. We report a novel approach to generate plasmons in Ga:ZnO (GZO) thin films in the wide spectral range of ∼1.87-10.04 eV. In the grown GZO thin films, dual-ion beam sputtering (DIBS) instigated plasmon is observed because of the formation of different metallic nanoclusters are reported. Moreover, formation of the nanoclusters and generation of plasmons are verified by field emission scanning electron microscope, electron energy loss spectra obtained by ultraviolet photoelectron spectroscopy, and spectroscopic ellipsometry analysis. Moreover, the calculation of valence bulk, valence surface, and particle plasmon resonance energies are performed, and indexing of each plasmon peaks with corresponding plasmon energy peak of the different nanoclusters is carried out. Further, the use of DIBS-instigated plasmon-enhanced GZO can be a novel mean to improve the performance of photovoltaic, photodetector, and sensing devices.