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We present a comprehensive analysis of elastic electron scattering from isoflurane in the intermediate energy range of 50-300 eV. This research is motivated by the significant impact of this molecule on global warming effects. We conducted this investigation through experimental measurements using a crossed-beam apparatus and covering a wide angular range from 25 to 125 degrees. Relative differential cross sections (DCSs) were obtained and subsequently normalized on an absolute scale by using the relative flow technique, with argon as the reference gas. These DCS values were then extrapolated and integrated to determine the experimental integral cross sections (ICSs). Additionally, we employed the independent atom model and the screening corrected additivity rule with incorporated Interference effects (IAM-SCAR+I) to calculate the theoretical differential and integral cross-sections. Remarkably, the calculated cross sections align closely with the experimental measurements across the entire energy and angular range. Furthermore, this study involved a comparison of the DCSs for isoflurane with previously published DCS values for two other volatile anesthetics, sevoflurane and halothane.

We present a combined theoretical and experimental absolute differential (DCS) and integral (ICS) cross sections for elastic electron scattering from halothane molecule in the intermediate energy range from 50 to 300 eV, which is motivated by its evident impact on global warming and ozone depletion. Experiments were carried out in the angular range from 20 to 110 degrees using a crossed-beam-based equipment. Using argon as the reference gas, relative DCSs were normalized on an absolute scale using the relative flow technique. These DCSs were then extrapolated and integrated to generate experimental ICS. With the use of an independent atom model and the screening corrected additivity rule with interference effects incorporated (IAM-SCAR+I), the theoretical differential and integral cross sections were calculated. In the whole energy and angular range, calculated cross sections agree well with experimental measurements.

The transmission of low-energy electrons through a macroscopic steel capillary has been investigated both experimentally and theoretically. The length of the steel capillary was L = 19.5 mm and the inner diameter was d = 0.9 mm. The kinetic energy distribution of electrons transmitted through the steel capillary was recorded for a tilt angle of psi = 2.6 degrees of the incident electron beam with respect to the capillary axis. Accompanying simulations based on classical transport theory reproduce the experimental data to a high degree of agreement. Transmission for other tilt angles has also been simulated to investigate the influence of the tilt angle on the guiding efficiency.

In this paper we describe the synthesis and characterization of the Sr2CeO4:Eu3+ nanopowder and possibilities of its application for temperature and high pressure sensing. The material was prepared using simple solution combustion synthesis. X-ray powder diffraction (XRD), scanning electron microscope (SEM) and photoluminescence (PL) techniques have been used to confirm and characterize the prepared material. Time resolved analysis of emission spectra was achieved by using the streak camera system. Measured lifetime values of luminescence emission and the intensity ratios of spectral lines were used for determining the calibration curves for remote temperature sensing. We have analyzed sensitivity improvement of the intensity ratio method by using a temporal evolution of emission lines and simulation of delayed gating of one of them. Pressure effects on optical properties of Sr2CeO4: Eu3+ nanophosphor are also investigated.

The gadolinium vanadate doped with samarium (GdVO 4 :Sm 3+ ) nanopowder was prepared by the solution combustion synthesis (SCS) method. After synthesis, in order to achieve the full crystallinity, the material was annealed in air atmosphere at 900°C. Phase identification in the postannealed powder samples was performed by X-ray diffraction, and morphology was investigated by high-resolution scanning electron microscopy (SEM). Photoluminescence characterization of the emission spectrum and time-resolved analysis have been performed using the tunable laser optical parametric oscillator excitation and the streak camera. Several strong emission bands in the Sm 3+ emission spectrum were observed, located at 567 nm ( 4 G 5/2 – 6 H 5/2 ), 604 nm ( 4 G 5/2 – 6 H 7/2 ), and 646 (654) nm ( 4 G 5/2 – 6 H 9/2 ), respectively. The weak emission bands at 533 nm ( 4 F 3/2 – 6 H 5/2 ) and 706 nm ( 4 G 5/2 – 6 H 11/2 ) and a weak broad luminescence emission band of VO 4 3− were also observed by the detection system. We analyzed the possibility of using the host luminescence for two-color temperature sensing. The proposed method is improved by introducing the temporal dependence in the line intensity ratio measurements.

In an effort to understand the vast complexity of the underlying processes within a cell at a molecular level, the first step lies in revealing the fundamental physical and chemical properties, as well as the structure, of biopolymers (proteins and DNA). With the development of modern experimental techniques it has become possible to study these large molecules under well-defined conditions in the gas phase, by closely inspecting their interactions with energetic photons and electrons. In this Thesis, we present the experimental setups for the action spectroscopy of peptides, proteins and nucleotides, as well as the hydrated complexes (hydrated nucleotides), in the gas phase. We present the details and the operation of the two experimental setups based on coupling the linear quadrupole ion trap with: (1) a VUV or a soft X-ray synchrotron beamline and (2) a focusing electron gun. In the case (1), the existing experimental setup consisting of a commercial quadrupole ion trap mass spectrometer (LTQ XL from Thermo Scientific), equipped with an electrospray ion source, was coupled to the VUV beamline DESIRS and the soft X-ray beamline PLEIADES at the synchrotron SOLEIL (France). The setups were used to study the photo-induced ionization/fragmentation of trapped biopolymers and nanosolvated species. The results obtained with this setups include VUV action spectroscopy of protonated Leucine-Enkephalin peptide (both a monomer and a dimer) and a nanosolvated nucleotide Adenosine monophosphate (AMP), in (5-15) eV photon energy range. The inner-shell action spectroscopy in the soft X-ray energy range (around C and N K-edge), was performed for multiply charged precursor of Ubiquitin protein. The photo-dissociation and photo-fragmentation ion yields for several fragment ions from all above mentioned macromolecules were extracted and the obtained spectral features were discussed considering relevant photon-induced processes. In the case (2), new experimental setup was developed b, U nastojanju da se razume ogromna složenost procesa u okviru ćelije na molekulskom nivou, prvi korak je otkrivanje fundamentalnih fizičko-hemijskih osobina, kao i strukture biopolimera (proteina i DNK). Razvojem savremenih eksperimentalnih tehnika omogućeno je proučavanje velikih biološki relevantnih molekula pod jasno definisanim uslovima u gasnoj fazi, izučavanjem njihovih interakcija sa fotonima i elektronima velikih energija. U ovom radu su predstavljene eksperimentalne postavke za akcionu spektroskopiju peptida, proteina, nukleotida, kao i nanosolvatisanih kompleksa (hidratisani nukleotidi) u gasnoj fazi. Prikazani su detalji i princip rada dve eksperimentalne postavke zasnovane na povezivanju linearne kvadrupolne jonske zamke sa: (1) sinhrotronskim fotonskim mlazom (VUV i meki X-zraci) i (2) fokusirajućim elektronskim topom. U slucaju (1), postojeća eksperimentalna aparatura koja sadrži linearnu kvadrupolnu jonsku zamku u okviru komercijalnog masenog spektrometra (LTQ XL od firme Thermo Scientific) povezana je sa VUV mlaznom linijom DESIRS i mlaznom linijom za meke X-zrake PLEIADES na sinhrotronu SOLEIL (Francuska). Aparatura je upotrebljena za izučavanje foto-indukovanih procesa jonizacije i fragmentacije zarobljenih jona biopolimera i nanosolvatisanih čestica. Rezultati dobijeni na ovoj aparaturi uključuju VUV akcionu spektroskopiju protonisanog leucin-enkefalin peptida (monomer i dimer), kao i nanosolvatisanog nukleotida adenosin monofosfata (AMP), u opsegu energija fotona od (5-15) eV. Akciona spektroskopija unutrašnje ljuske koristeći meke X-zrake (u oblasti C i N K-ljuske), urađena je za višestruko naelektrisani prekursor proteina ubikuitin. Za sve gore pomenute makromolekule, izučavani su absorpcioni spektri za neke od dobijenih jonskih produkata, pri čemu su analizirane uočene spektralne karakteristike dobijene u pomenutim fotonski indukovanim procesima. U slucaju (2) razvijen je novi eksperimentalni sistem zasnovan na povezivanju iste LTQ XL jonske za

In this work we study the transmission of charged particles through a single cylindrically shaped metallic capillary of microscopic dimensions with a large aspect ratio. We used electrons as projectiles. Our results suggest the existence of guiding of the electron beam by a metallic capillary.

We have measured 200 eV electron transmission through a single platinum tube of a diameter of 3.3 mm. We find that the transmission of electrons can be detected even at large tilt angles, where the tube is not transparent geometrically. The transmission drops down exponentially with increasing the tilt angle. The energy spectrum of detected electrons behind the tube contain contributions at lower energies due to both inelastic scattering and secondary electron emission. The spectrum is qualitatively in good agreement with the calculations performed for the flat Pt surface in order to understand and model the electron interaction processes that define the transmission and the energy spectrum at the exit. (C) 2014 Elsevier B.V. All rights reserved.

Nanopowders based on gadolinium zirconium oxide (Gd2Zr2O7) doped by europium ions (Eu3+) were successfully prepared using a flame combustion method. This material is suitable for various optical devices. The structure of prepared materials has been confirmed and characterized using X-ray powder diffraction (XRD), scanning electron microscope (SEM) and photoluminescence (PL) techniques. The luminescence properties of synthesized nanopowders were characterized by emission spectra and luminescence lifetimes by using the streak camera system. PL spectra were obtained at three different excitation wavelengths (Optical Parametric Oscilator (OPO) at 360 nm, laser diode at 365 nm and Ar laser line at 514.5 nm). The strong emission lines at 611 nm and 630 nm corresponding to the D-5(0) - GT F-7(2) long lived transition could be used as a new red light source in optical devices. (C) 2014 Elsevier B.V. All rights reserved.

U ovoj disertaciji proučavana je interakcija elektrona srednjih energija, 40 eV – 300 eV, sa molekulima analognim delovima DNK (furan, 3-hidroksitetrahidrofuran, pirimidin) i proteina (formamid i N-metilformamid). Opisana je eksperimentalna procedura za merenje relativnih i apsolutnih efikasnih preseka (metod relativnih protoka) za elastično rasejanje elektrona na biomolekulima, kao i merenje raspodele kinetičke energije pozitivnih jona. Apsolutni diferencijalni preseci (differential cross sections – DCSs) za elastično rasejanje elektrona na molekulima su predstavljeni tabelarno i grafički, u funkciji ugla rasejanja i upadne energije elektrona. Takođe su opisani relevantni teorijski proračuni (IAM, SCAR, SCARN, SCARND) sa kojima su eksperimentalni rezultati bili upoređeni. Dobijeno je veoma dobro slaganje eksperimentalnih i teorijskih efikasnih preseka, a mala neslaganja su viđena samo na malim uglovima i nižim upadnim energijama elektrona. Takođe, u radu je korišćena prva Bornova aproksimacija za procenu doprinosa vibracionih neelastičnih preseka za rasejanje elektrona na molekulu furana, pošto eksperimentalna merenja (s obzirom na energijsku rezoluciju) ne mogu odrediti ovaj doprinos, niti SCARND teorija uračunava ove neelastične procese. Ova aproksimacija je potvrdila da je moguće odstupanje od apsolutnih eksperimentalnih elastičnih preseka u okviru apsolutne greške merenja. Generalno, apsolutni diferencijalni preseci za sve molekule su slični po obliku i na apsolutnoj skali. Uporedili smo rezultate za furan, 3HTHF i THF na 100 eV. Ovi rezultati su vrlo bliski na apsolutnoj skali, pokazujući sličnu redistribuciju rasejanih elektrona na sve 3 mete. Takođe su upoređeni i rezultati za formamid i NMF. Dodatno, ugaona zavisnost razlike apsolutnih preseka za ova dva molekula je upoređena sa objavljenim presecima za metan (CH4), pokazujući jako dobro slaganje i potvrđujući primenljivost principa gradivnih blokova za procenu preseka za elastično rasejanje elektrona u ovo, The experimental investigation of electron interaction with biomolecules that are analogues to building blocks of DNA (furan, 3-hydroxytetrahydrofuran and pyrimidine) and proteins (formamide, N-methylformamide), at medium incident electron energies 40 eV – 300 eV, is presented in this thesis. An experimental procedure for the measurement of both relative and absolute cross sections (by using relative flow method) for elastic electron scattering from biomolecules, as well as the measurement of kinetic energy distribution of positive ions, has been described. Absolute differential cross sections (DCSs) for elastic electron scattering from all investigated molecular targets are tabulated and graphically presented as a function of both the scattering angle and the incident electron energy. Also, relevant theoretical models (IAM, SCAR, SCARN, SCARND) have been described and the obtained calculated results compared with our experimental results. The theoretical and the experimental cross sections are in a very good agreement, with some deviations at small scattering angles and low incident electron energies. Furthermore, the first Born approximation has been used in the present work in order to estimate a contribution of vibrationally inelastic DCSs for furan molecule, since neither experimental measurement (due to the energy resolution) or SCARND calculations can resolve this contribution. The present calculations confirm that a possible deviation of the experimental absolute elastic DCSs should be within reported absolute errors. Generaly, absolute differential cross sections for all investigated molecules are similar both in the shape and on the absolute scale. We have compared results for furan, 3HTHF, and THF at 100 eV, which are very close on the absolute scale, thus showing a similar redistribution of scattered electrons for all three targets. The results for formamide and NMF have been also compared. Additionally, the angular dependence of a distinction between th

In this contribution we present a progress report on two atomic and molecular databases, BEAMDB and MolD, which are web services at the Serbian virtual observatory (SerVO) and nodes within the Virtual Atomic and Molecular Data Center (VAMDC). The Belgrade Electron/Atom (Molecule) DataBase (BEAMDB) provides collisional data for electron interactions with atoms and molecules. The Photodissociation (MolD) database contains photo-dissociation cross sections for individual rovibrational states of diatomic molecular ions and rate coefficients for the chemi-ionisation/recombination processes. We also present a progress report on the major upgrade of these databases and plans for the future. As an example of how the data from the BEAMDB may be used, a review of electron scattering from methane is described.

In this contribution we present a progress report on two atomic and molecular databases, BEAMDB and MolD, which are web services at the Serbian virtual observatory (SerVO) and nodes within the Virtual Atomic and Molecular Data Center (VAMDC). The Belgrade Electron/Atom (Molecule) DataBase (BEAMDB) provides collisional data for electron interactions with atoms and molecules. The Photodissociation (MolD) database contains photo-dissociation cross sections for individual rovibrational states of diatomic molecular ions and rate coefficients for the chemi-ionisation/recombination processes. We also present a progress report on the major upgrade of these databases and plans for the future. As an example of how the data from the BEAMDB may be used, a review of electron scattering from methane is described.