An electron spectroscopic study of the adsorption of nitrogen on a Ni/TiO2 catalyst prepared in situ in the spectrometer: evidence for dissociative adsorption in the strong-metal-support-interaction (SMSI) state

Nitrogen is dissociatively adsorbed on an annealed Ni/TiO2 surface just as on a Ti–Ni alloy surface while it is molecularly adsorbed on a Ni/Al2O3 surface.

An infrared spectroscopic study of the low-spin-high-spin transition in FexMn1-x(Phen)2(NCS)2: A composition-induced change in the order of the spin-state transition

Infrared spectroscopy provides a valuable tool to investigate the spin-state transition in Fe(II) complexes of the type Fe(Phen)2(NCS)2. With progressive substitution of Fe by Mn, the first-order transition changes over to a second-order transition, with a high residual population of the high-spin state even at very low temperatures

A Photoelectron Spectroscopic Study Of The Interaction Of Oxygen, Nitrogen And Transition-Metals With C-60 Films

Evidence is presented for the strong interaction of oxygen and nitrogen with solid films of buckminsterfullerene based on core-level spectroscopic studies. Cr, Ni and Cu deposited on C60 films interact strongly giving rise to large changes in the C(Is) and C(2p) binding energies as well as the (2p) binding energies of the transition metals.

Electron energy loss spectroscopic study of Cr(CO)6, Mo(CO)6 and W(CO)6 in the vapour phase

Electron energy loss spectra (EELS) of Cr, Mo and W hexacarbonyls in the vapour phase are reported. Most of the bands observed are similar to those in optical spectra, but the two high energy transitions in the 9·8–11·2 eV region are reported here for the first time. Based on the orbital energies from the ultraviolet photoelectron spectra and the electronic transition energies from EELS and earlier optical studies, the molecular energy level schemes of these molecules are constructed.

AC impedance spectroscopic characterization of 10 mol% MgO doped ZnO varistors

The performance parameters e.g. non-linear coefficient (α) and breakdown electric field (Eb1mA/cm2) of ZnO based ceramic varistors were found to improve after the addition of 10 mol% MgO. The improvement in the varistor properties is examined by ac impedance spectroscopy technique in the frequency range (1 Hz–10 MHz) between temperature 25–250°C and understood in terms of differing contributions from the equivalent electrical circuit elements.

An infrared spectroscopic study of the orientational phase transitions of C70

Infrared spectroscopic studies of C70 films show variation in absorbance and linewidth of the bands across the orientational phase transitions around 280 and 340 K. There is some evidence for the coexistence of phases in the 210–270 K region and for the occurrence of another transition below 200 K.

Victims of the White War or Rebellions of the Green Revolution? Bolivian Indigenous Women Prisoners' Position in the "War on Drugs" Explored through a Criminological Gaze

Tässä tutkielmassa tarkastellaan Bolivialaisten naisvankien (alkuperäisväestön) ja globaalin huumesodan ("War on Drugs") välistä yhteyttä. Keskustelu sijoitetaan laajemmin kokan viljelyn politiikkaan ja alkuperäisväestön kulttuuriin. Kokaa viljeleviä köyhiä maalaisia, joista huomattava osa on naisia, on vangittu Boliviassa kiihtyvää tahtia viime vuosikymmeninä. Moni naisista on kokan tuotannossa ja kaupassa mukana, sillä se on monesti ainoa keino taloudelliseen selviämiseen. Yleisesti ottaen naisvangit ja naisrikolliset ovat marginaalinen ilmiö. Kansainvälisesti tarkasteltuna naisvankien suhteellinen osuus koko vankilaväestöstä on noin 5,2 % (keskiarvo). Boliviassa osuus on vaihdellut 6,1 %:n ja 17,1 %:n välillä vuosina 2000-2008. Naisvankien määrä yleisesti ottaen on ollut rajussa kasvussa, suurin syy naisten vangitsemiseen on huumausaineisiin liittyvät rikokset. Näyttää myös siltä että vähemmistöt ja etnisen taustan omaavat henkilöt ovat yliedustettuina vankilaväestössä. Bolivia seuraa tätä kansainvälistä trendiä. Tämä tutkielma on rajattu kysymyksiin Bolivian intiaaniperäisten naisten osuudesta maan huumerikollisuudessa, sekä heidän suhteellisen korkeaa vangitsemisastetta selittäviin yhteiskunnallisiin tekijöihin. Kysymykset sukupuolesta, etnisyydestä ja kokan viljelyn politiikasta ovat keskiössä. Yleisiä kriminologisia teorioita peilataan kriittisesti suhteessa aineistoon ja Bolivian kontekstiin. Huumesodan ja Bolivian ankaran huumelainsäädännön seurauksista keskustellaan kriittisesti, sekä pohditaan köyhän alkuperäisväestön massavangitsemisen tarpeellisuutta. Tutkimuskysymykseni ovat: mitkä tekijät selittävät kohtuullisen korkean intiaaniperäisten naisvankien määrän Boliviassa, ja mikä on heidän asemansa globaalissa huumesodassa? Tutkielmassa on analysoitu kvantitatiivista ja kvalitatiivista aineistoa. Päälähteenä on ollut Bolivian tilastokeskuksen tuottamat rikostilastot. Tutkielman tärkeimpänä löydöksenä voidaan pitää havaintoa, että vastoin tiettyjä olettamuksia, intiaaniperäiset naiset ovat hyvinkin aktiivisia perinteisesti miehisiksi käsitetyillä aloilla kuten rikollisuudessa ja politiikassa. Tutkielmassa osoitetaan myös, että pidätysten määrät ovat moninkertaistuneet muutamassa vuosikymmenessä. Koska kokan viljelyssä on kyse pääasiallisesti taloudellisesta toimeentulosta, tämä tutkielma kysyy, onko hengissä pysyminen rikos?

Noble metal ionic sites for catalytic hydrogen combustion: spectroscopic insights

A catalytic hydrogen combustion reaction was carried out over noble metal catalysts substituted in ZrO2 and TiO2 in ionic form. The catalysts were synthesized by the solution combustion technique. The compounds showed high activity and CO tolerance for the reaction. The activity of Pd and Pt ion substituted TiO2 was comparable and was higher than Pd and Pt ion substituted ZrO2. The mechanisms of the reaction over the two supports were proposed by making use of the X-ray photoelectron spectroscopy and FT infrared spectroscopic observations. The reaction over ZrO2 supported catalysts was proposed to take place by the utilization of the surface hydroxyl groups while the reaction over TiO2 supported catalysts was hypothesized to be a hybrid mechanism utilizing surface hydroxyl groups and the lattice oxygen.

Electronic absorption and emission spectroscopic investigations of the interaction of the fullerenes, C60 and C70, with amines and aromatic molecules

Electronic absorption spectroscopy and fluorescence spectroscopy have been used to investigate the interaction of the fullerenes C60 and C70 with diethylaniline, and with aromatic solvents such as benzene. C60 interacts weakly with aromatic amines in the ground state while C70 does not interact at all. Steady state fluorescence emission and lifetime measurements show that both C60 and C70 form excited state complexes (exciplexes) with the amines in non-aromatic solvents such as methylcyclohexane, but not in benzene. In benzene, only fluorescence quenching is observed due to the interaction between the π systems of the aromatic solvent and the fullerene in the ground state. This is also borne out by the systematic study of solvent effects on the absorption and emission spectra of the fullerenes.

Electron spectroscopic investigation of the semiconductor-metal transition in La1-xSrxMnO3

We study the electronic structure of La1-xSrxMnO3+δ, x=0, 0.1, 0.2, 0.3, and 0.4, across the semiconductor-metal transition, using various electron spectroscopy techniques. The negligible intensity seen at EF using ultraviolet photoemission spectroscopy and bremsstrahlung isochromat spectroscopy (BIS) indicate an unusual semiconductor-metal transition observed for x≥0.2, consistent with the resistivity data. The BIS spectra show doped hole states developing about 1.4 eV above EF as a function of x. Auger electron spectroscopy gives an estimate of the intra-atomic Coulomb energy in the O 2p manifold to be about 6.8 eV. The Mn 2p core-level spectrum of LaMnO3, analyzed in terms of a configuration-interaction calculation, gives parameter values of the charge-transfer energy Δ=5.0 eV, the hybridization strength between Mn 3d and O 2p states, t=3.8 eV, and the on-site Coulomb energy in Mn 3d states Udd=4.0 eV, suggesting a mixed character for the ground state of LaMnO3.

Organometallic chemistry of diphosphazanes *1: VIII. Synthesis, spectroscopic studies and crystal structure of fac-[Mo(CO)3(MeCN)Ph2PN(iPr)P(Ph)(DMP)], and its reactions with tertiary phosphines

The reaction of fac-[Mo(CO)3(MeCN)3] with the unsymmetrical diphosphazane Ph2PN(iPr)P(Ph)(DMP) (L) gives the complex fac-[Mo(CO)3(MeCN)(L)] (2) in almost quantitative yield. The structure of the complex has been determined by an X-ray diffraction study. The compound reacts with PR3 (where R = Ph, OPh) to give fac-[Mo(CO)3(PR3)(L)] (3a, 4a), which undergoes an intramolecular isomerization to afford mer-[Mo(CO)3(PR3)(L)] (3b, 4b). Synthesis of cis-[Mo(CO)4(L)] (1) and fac-[MO(CO)3L] (2a) and their spectroscopic data are also reported.

Orientational phase transitions in C70: A Raman spectroscopic investigation

Raman investigations of C70 films in the 14-370-K range show significant changes across the orientational phase transitions around 270 and 330 K. Seven of the Raman modes of C70 soften smoothly across the transitions, the magnitude of the decrease in frequencies being in the range of 2-5 cm-1. Linewidths of the bands increase in the transition region over and above the anharmonic contributions.

Pressure-induced phase transitions in LiRbSO4: a Raman spectroscopic study

Room-temperature Raman spectra of LiRbSO4 were studied as a function of pressure up to 170 kbar for two different orientations of the crystal. Four pressure-induced phase transitions at about 2, 17, 32 and 57 kbar were observed. The transitions at 17 and 57 kbar have slow kinetics, taking about 4 h for their completion. These phase transitions are associated with the orientations of the SO4 ions in the unit cell.