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The variable configuration of Raman spectroscopic platforms is one of the major obstacles in establishing Raman spectroscopy as a valuable physicochemical method within real-world scenarios such as clinical diagnostics. For such real world applications like diagnostic classification, the models should ideally be usable to predict data from different setups. Whether it is done by training a rugged model with data from many setups or by a primary-replica strategy where models are developed on a 'primary' setup and the test data are generated on 'replicate' setups, this is only possible if the Raman spectra from different setups are consistent, reproducible, and comparable. However, Raman spectra can be highly sensitive to the measurement conditions, and they change from setup to setup even if the same samples are measured. Although increasingly recognized as an issue, the dependence of the Raman spectra on the instrumental configuration is far from being fully understood and great effort is needed to address the resulting spectral variations and to correct for them. To make the severity of the situation clear, we present a round robin experiment investigating the comparability of 35 Raman spectroscopic devices with different configurations in 15 institutes within seven European countries from the COST (European Cooperation in Science and Technology) action Raman4clinics. The experiment was developed in a fashion that allows various instrumental configurations ranging from highly confocal setups to fibre-optic based systems with different excitation wavelengths. We illustrate the spectral variations caused by the instrumental configurations from the perspectives of peak shifts, intensity variations, peak widths, and noise levels. We conclude this contribution with recommendations that may help to improve the inter-laboratory studies. © 2020 American Chemical Society.

When implanting (111) GaAs with boron and heavier argon ions, severe distortion of crystal structure occurs. The Raman scattering has shown that with implanted ion dose change the crystal structure gradually transforms into disordered state, in which coexistence of crystalline, microcrystalline, nanocrystalline and amorphous phases is possible. At the certain stage of implantation the formation of continuous amorphous layer of GaAs takes place. The critical doses of disorder and amorphization of GaAs at implantation with B and Ar ions accordingly have been defined. The graphs of dependence of LO and TO phonon halfwidths upon implantation doses are also the characteristics of amorphization. The possibility of estimation of quantitative portions of the amorphous and nano phases from the Raman-spectra is emphasized. It is shown experimentally that using light ions to synthesize nano GaAs most likely is more advantageous: the nano phase synthesizes in the wide range of fluencies (at high fluencies too). (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

27th European Photovoltaic Solar Energy Conference and Exhibition; 2772-2775, This paper involves characterization of ZnSe thin films and photovoltaic cells prepared by close spaced sublimation method. Solar cells with structure SnO2/ZnSe/CdTe were obtained and compared with the SnO2/CdS/CdTe fabricated under the same conditions at Moldova State University. The SEM and XRD studies of ZnSe thin films show that the structure is polycrystalline and depends on the thickness of the films. The optical transmittance spectra indicate that an average transmission of above 80% was obtained in the visible range. All photovoltaic cells were characterized through light and dark current density-voltage (J-V) and quantum efficiency (EQE) measurements. The preliminary results obtained for ZnSe/CdTe cells are: Jsc = 20.8 mA/cm2, Uoc= 0.63V, FF = 0.42 and = 5.5% with irradiance of 100 mW/cm2. The solar cells fabricated using CdS buffer layers gave the following results: Jsc = 23.9 mA/cm2, Uoc= 0.79 V, FF = 0.51 and = 9.6%.

Natural minerals α‐HgS from various mines have been studied by laser Raman‐spectroscopy and resonance Raman‐spectroscopy. The crystals differ from each other in the content of selenium impurities included in samples from different mines. Based on Raman spectra and factor‐group analyze the classification the first order phonons and then the comparison the results with the results from other works are carried out. The Raman spectra analysis of minerals from various mines show the presence of selenium impurity gap vibration at 203 cm−1 and 226 cm−1 frequencies respectively. On the statistical basis of the Raman measurements, one can conclude that the frequencies of impurities of α‐HgS generally may be used for identifying mines. Low resonance has been fixed as well in impure minerals at spectral band frequency 203 cm−1 characterizing vibrationgap of isomorphic Se impurity in cinnabar.

This work follows a paper reporting on a study on an interaction of hematin with antimalarial drug chloroquine by the use of resonance Raman spectroscopical investigation technique. Whereas this previous results have been made using hematin solution, we have performed an in vitro experiment in order to verify the detection of the ν 19 mode, by depolarization ratio behavior higher than 3/4, when the excitation wavelength of the laser is chosen to be resonant with Q-band absorption. Such high depolarization has not been observed in our investigation. On the other hand, we have investigated the interaction of chloroquine derivatives with malaria-infected red blood cell as well as hydroartemisinin activities, using excitation wavelengths at 514nm and 785nm. We compare and discuss the resonance Raman spectra of hemozoin-CQ complex and free hemozoin, after 4 hours and 24 hours for the range of 1200cm -1 to 1750cm -1.

The resistance of pressure equipment is currently tested, before commissioning or at periodic maintenance, by means of normal pressure tests. Defects occurring inside materials during the execution of these tests or not seen by usual non-destructive techniques can remain as undetected potential sources of failure . The acoustic emission (AE) technique can detect and monitor the evolution of such failures. Industrial-size helium cryogenic systems employ cryogens often stored in gaseous form under pressure at ambient temperature. Standard initial and periodic pressure testing imposes operational constraints which other complementary testing methods, such as AE, could significantly alleviate. Recent reception testing of 250 m3 GHe storage vessels with a design pressure of 2.2 MPa for the LEP and LHC cryogenic systems has implemented AE with the above-mentioned aims.

Testing superconducting magnets for the Large Hadron Collider (LHC) in superfluid helium requires large-capacity refrigeration at 1.8K. At CERN, this is provided by a combination of a cold compressor and a set of warm vacuum pumps capable of handling up to 18g/s at 1 kPa suction pressure. The cold helium vapour, after the cold compressor, is warmed up from about 5K to ambient temperature in a 32 kW electrical heater. The device is designed to operate reliably at flow rates varying from 1 to 18g/s, inlet pressure of 1 kPa to 3 kPa, with pressure drop 100 Pa. Design and construction of the heater, completely realised at CERN, are presented, as well as measured performance. Some technological problems are discussed.

Natural minerals α-HgS from various mines have been studied by laser Raman spectroscopy and resonance Raman spectroscopy. The crystals differ from each other in the content of selenium impurity, included in samples from some mines.Based on the Raman spectra and the factor-group analysis the classification of the first order phonons and then the comparison of the results with the results from other works were carried out. The Raman spectra analysis of minerals from various mines show the selenium impurity gap vibration at 203 cm−1 and 226 cm−1 frequencies, respectively. On the basis of statistical measurements of the Raman spectra one can conclude that impurity frequencies of α-HgS may be generally used for the identification of the mine.Resonance Raman scattering for pure minerals has been studied by a dye laser. Phonon resonance in the indirect semiconductor α-HgS is found to be far more intense than the indirect resonance detected until now in various semiconductors in the proximity of the first indirect band Eg, for instance, in GaP. In our opinion, this may be conditioned by cinnabar band structure peculiarities.Low resonance has also been fixed in 'dirty' minerals at the spectral band frequency of 203 cm−1 characterizing gap vibration of isomorphic impurity Se in cinnabar.