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The appropriate use of Information and Communication Technology (ICT) along with Modern Teaching Practices (MTPs), such as flipped learning and project-based learning, can increase the efficiency of teaching and learning in the higher education (HE) process. To ensure effective implementation of ICT and MTPs, the University of Maribor (UM) has established institutional support in the form of the Centre for Teaching Support of the University of Maribor (CTSUM), which is available to university teachers of all 17 UM faculties. The CTSUM provides support for the use of ICT and implementation of MTPs through individual consultations and workshops. This study aims to assess teachers’ interests and needs in the field of ICT and MTPs along with the self-evaluation of their existing ICT skills. It was conducted as an online survey with responses from 154 teachers (approx. 26% response rate). The results show that a significant majority of teachers are interested in the provided support and need training on the use of ICT for preparing interactive assignments, voting and providing feedback, performing project-based learning, designing graphically rich study materials, and organising course materials online. The obtained information helps the CTSUM prepare customised workshops and consultations aimed at strengthening teachers’ digital literacy and didactic skills.

The Hel photoelectron spectra of benzamide (1), 2-hydroxybenzamide (salicylamide, 2), N-phenylacetamide (acetanilide, 3), N-(4-hydroxyphenyl) acetamide (paracetamol, 4), and N-(4-ethoxyphenyl) acetamide (phenacetine, 5) have been recorded and analyzed. A tactical approach similar to the composite molecule analysis of benzoic acid derivatives (T. Meeks, A. Wahlborg and S. P. McGlynn, J. Electron Spectrosc. 22, 43 (1981) was used to determine the electronic structure of 1–5. The interaction of the benzene ring with the amidic group and the role of the benzenoid moiety in the biological activity of these compounds is emphasized.

The correlation of photoelectron (PE) spectra of amino acids and their methyl esters shows that the gas-phase electronic structure of the acid can be deduced from results for its ester. Such a procedure is also supported by comparison of PE spectra of carboxylic acids and their methyl (and ethyl) esters. The results indicate that amino acids and free esters in the gas phase appear in their molecular form.

The equilibrium conformations of bispidine and its N , N ′ -dimethyl derivative were investigated with the ab initio MP2 formalism and the density functional theory (DFT) ansatz B3LYP. For bispidine, the chair–chair (cc) ( exo , endo ) is the most stable conformer. On the contrary, for its N , N ′ -dimethyl derivative, the energy difference between the cc and chair–boat (cb) conformers is small, allowing for conformational mobility of the bicyclo rings. For tetraaza-macrocycle with four nitrogen lone pair orbitals (LPOs) pointing into the molecular cavity, the C 2h structure with stepped ethylene bridges is preferred over the twisted structure of D 2 symmetry. Mono- and di-protonated forms of this base are characterized by intramolecular asymmetric hydrogen bonds. All the theoretical conformational predictions are consistent with the available experimental results. The NMR chemical shifts, calculated by the continuous set of gauge transformations (CSGT) formalism with the DFT/B3LYP method, are fairly consistent with NMR observation. The He(I) photoelectron (PE) spectra were measured and assigned by means of ab initio outer valence Green's function (OVGF) calculations. The predominance of the lowest energy conformation of bispidine and tetraaza-macrocycle is supported by the spectroscopic results. The conformational situation for N , N ′ -dimethyl-bispidine is more complex. Whereas its NMR spectrum indicates a predominance of the cc conformer in THF-d 8 solution, the vibrational and PE spectra should be interpreted in terms of a mixture of the cc and cb conformers in the neat liquid and gas-phase.

The distribution of DNA molecular lesions is defined as the histogram of lesion occurrence probability versus lesion type and is termed a molecular lesion spectrum (MLS). The MLSs for 405 nm, 254 nm and ? ray electromagnetic radiations are investigated here, and it is shown that eight, five, four, three and two lesion sets function as very good radiation signatures; that is, MLSs based upon these lesion sets can be used to identify the causal electromagnetic radiation. The approach adopted is based on pattern recognition techniques couched in neural network formalism, the patterns being defined as vectors and their uniqueness described as a degree of vector orthogonality. The minimal lesion set for signature of the three radiations is found to consist of two lesions, thymine dimer (d) and locally multiply damaged site (lmds) lesions. This is a surprising finding, and it works only because the d lesion turns out to be a radiation marker for 254 nm radiation and the lmds lesion to be a radiation marker for ? rays. Since these findings about signatures and markers are important from safety, insurance and medical aspects, it is well to caution that only three radiations, all electromagnetic, have been investigated here. Work on particulate and other electromagnetic radiations is underway.

High resolution He(I) photoelectron spectra (PES) of a number of bromo- and iodoalkanes have been measured. Linear relationships between ionization energies (Ei) and 1/n (where n is the number of carbon atoms in the chain) describe the trends reasonably well if n = 1 is excluded for dihaloalkanes. This property (i.e. line slopes) when joined the alternation of halogen lone pair bandwidths within a given spin—orbit doublet, can be used to provide a fully empirical assignment of the four non-bonding orbital ionizations of dihaloalkanes. The interactions between the halogen lone pair orbitals and the alkane σ orbitals dominate in dihaloalkanes for which n⩾2, while through-space interaction is important only in dihalomethanes (n = 1). Vibrational fine structures were used to infer the existence of hyperconjugative effects.

Results of 10 years of ozone monitoring in the Adriatic and Aegean coastal region are presented. A high level of ozone production with a characteristic and pronounced diurnal variation in urban and industrial areas during the summer has been observed leading to local photosmog episodes. Owing to the absence of sinks the concentrations remain high at remote sites. Deviations from typical behaviour are discussed in terms of transport of ozone itself or its precursors.

A review of recent results on the production, destruction and transport of tropospheric ozone in the eastern Mediterranean is given. Measurements from several locations on the Croatian Adriatic coast, Greater Athens, Thessaloniki and Cairo regions are used as demonstrations.

Natural polymers, humic acid and lignins, were investigated by laser desorption (LD) Fourier transform mass spectrometry. In the vapor phase under LD conditions only positive ions of humic acid were observed up to m/z 700. Under the same conditions all the lignins investigated prefer to form negative ions of the individual oligomers at well-defined mass spacings and with a distribution from m/z several hundred to 3OOO. Three sequences with Am-444 confirm the existence of stable trimer building blocks in the coniferous lignins.

Ozone is a naturally occurring gas, formed in the trimolecular reaction of oxygen atoms with molecular oxygen. Its strong absorption in the UV region provides protection from excessive irradiation of the Earth's surface. Occupational exposure to ozone involves electric arc welding, mercury vapour lamps, office photocopy machines, X-ray generators and other high voltage electrical equipment, water purification and bleaching. Ozone is the most abundant oxidant in the photochemical smog. The lung cell injury induced by ozone involves a complex biochemical mechanism which is due to free radical generation. Moderate exposure produces upper respiratory tract symptoms and eye irritation, severe acute exposure results in pulmonary oedema. Measurements of atmospheric ozone concentrations in Croatia began at the end of the 19th century; continuous monitoring has been carried out since 1975.

U radu se razglaba o ozonu kao prirodnom sastojku atmosfere, nepovoljnu učinku smanjenja ozonskog omotača te porastu koncentracije ozona u troposferi. Dan je prikaz pojedinih industrijskih grana gdje je ozon prisutan uz osvrt na ambijentalnu izloženost. Također se razglaba o akutnoj i kroničnoj toksičnosti ozona te patofiziološkim mehanizmima djelovanja ozona na tkiva, napose na respiratorni sustav. Spominju se mjerenja ozona u Hrvatskoj s kraja 19. stoljeća te ona započeta nakon 1975. koja i danas traju., Ozone is a naturally occurring gas, formed in the trimolecular reaction of oxygen atoms with molecular oxygen. Its strong absorption in the UV region provides protection from excessive irradiation of the Earth's surface. Occupational exposure to ozone involves electric are welding, mercury vapour lamps, office photocopy machines. X-ray generators and other high voltage electrical equipment, water purification and bleaching. Ozone is the most abundant oxidant in the photochemical smog. The lung cell injury induced by ozone involves a complex biochemical mechanism which is due to free radical generation. Moderate exposure produces upper respiratory tract symptoms and eye irritation, severe acute exposure results in pulmonary oedema. Measurements of atmospheric ozone concentrations in Croatia began at the end of the 19th century; continuous monitoring has been earned out since 1975.

Ozone formation in the greater Cairo area was studied in 1990 in a 3-week measurement period performed at three sites (Shoubra El-Kheima, Mokattam Hill, Helwan), covering a north-south direction of 27 km, and in 1991, from the beginning of April until the end of October, by measurement of the seasonal variation of ozone at one site at El-Kobba. The sinusoidal shape in the diurnal volume fraction plots with peak values of 120 ppb and daily mean value of 50 ppb throughout the year indicate a substantial contribution of photochemistry to the ozone content of the atmosphere. Ozone is produced predominantly over the industrial area in the north and in the centre of Cairo and transported southward by the prevailing northerly winds. Contrary to many urban areas in Europe and in North America, fairly high average ozone levels of 40 ppb are observed during the night throughout the spring and the summer. This may imply that health hazards and crop damage are higher in the greater Cairo area than in Central Europe.

The laser optogalvanic (LOG) spectrum of cesium vapor at —50 m Torr in a low power (Si W), —30 MHz radiofrequency discharge has been recorded in the range 16,250 to 16,860 cm-1. Members of several Rydberg series (6p -► ns, 6p -» nd, 5d -* np and 5d -► nf) that terminate on the first ionization limit have been observed. The line broadening of high-n (ns30) f- levels in cesium is considerably less than in xenon. The excessive broadening in xenon is attributed in part to interactions of the Rydberg electron with the open- shell core.

Ozone is formed in the lower troposphere through photochemical reactions involving primary pollutants such as nitrogen oxides and hydrocarbons. It is also destroyed by many oxidizable pollutants such as nitrogen oxide and unsaturated hydrocarbons. Its concentration in ambient air is therefore a function of pollutant emissions, solar irradiance and of transport. During the past decade we have taken part in ozone monitoring in various locations in the eastern Mediterranean region. These included urban sites (Split, Athens, Cairo), places relatively close to large urban centres (island of Krk near Rijeka and the island of Aegina south of Athens) and relatively remote sites on the island of Iz in the central Adriatic and the island of Paros in the central Aegean sea. Here we want to describe the observed characteristic behaviour of ozone volume fractions in such places.

Chemistry assumes that electrons moving in the potential field of nuclei are crucial to the existence of those forces that define the formation, properties and reaction of chemical compounds. A theoretical approach that adopts this view is the orbital (atomic, AO, or molecular, MO) concept. The orbital concept is concerned with the motion of electrons in the average field of a complicated system of particles (including electrons), and it assumes that the results bear on reality. The success of the method is well documented and the difficulties it encounters, particularly when applied to molecular spectroscopy, have been elaborated [1].

The He I photoelectron (PE) spectra of the 77 lignin subunits were measured and arranged in classes of compounds according to the following functional groups: aldehydes, ketones, alcohols, carboxylic acids, functionalized polymethyl benzenes and miscellaneous lignin subunits. In all spectra the highest occupied molecular orbital (HOMO) was assigned to a jt-orbital.

13C labeling of 2,4,5-triphenyloxazole reveals that the loss of CO occurs with ring opening at OC(2) bond and migration of the C(5) phenyl group to the C(4) and C(2) positions.

The HeI photoelectron (PE) spectra of indole (1), benzimidazole (2), indazole (3), 3-chloro-indazole (4), imidazo[1,2-b]pyridazine (5), 6-chloroimidazo[1,2-b]pyridazine (6), 2-phenyl-imidazo[1,2-b]pyridazine (7), 2-phenyl-6-chloroimidazo[1,2-b]pyridazine (8), tetrazolo[1,2-a]-pyridine (9) and 8-cyanotetrazolo[1,5-a]pyridine (10) have been recorded. The spectra of 2–10 are of special interest for studying lone pair interactions. The assignment of the PE spectra submitted here, conjointly with the electronic structure of the studied compounds is discussed on the basis of molecular orbital calculations.

A new technique for low-pressure photoacoustic spectroscopy, one in which a low-power radio-frequency discharge is used as a sensitive acoustic-wave sensor, is presented. This contactless technique is a variation of the laser-optogalvanic method and is termed PARFLOG (photoacoustics using radio-frequency laser-optogalvanic detection).The ability to prosecute low-pressure photoacoustic measurement at a reduced level of collisional perturbations enables us to study intramolecular processes such as level crossings, predissociation, field effects, etc. Results for magnetic predissociation of the [Formula: see text] state of iodine are presented.

The concentrations of six PAHs (benzo[a]pyrene, benzo[b]fluoranthene, ideno[1,2,3-c,d]-pyrene, benzo[a]anthracene, benzo[k]fluoranthene and fluoranthene), and lead have been measured systematically for six winter periods from 1977/78 to 1982/83 in the urban air of the city of Zagreb. The average mass concentrations of PAHs were approximately 10 ng m-3. The distribution of PAHs in urban air is discussed. The analytical method for PAH determination is based on filter extraction, two-dimensional thin-layer chromatography and fluorescence spectrometry; lead is measured by atomic absorption.

The electronic transitions in 5H-dibenzo (a,d)-cycloheptene (1), 5H-dibenz(b,f)azepine (2), dibenz( b,f)oxepine (3), 5-dibenzo(a,d)cyclohepten-5-one (4), dibenzo(b,f)thiepine (5) and dibenzo (b,f) selenepine (6) have been calculated by the SCF LCAO MO CI method for model conformations and compared with experimental uv absorption spectra. The spectral characteristics and conformations of the title compounds and their relationship to cis-stilbene and o-substituted cis-stilbenes are discussed.

The He(I) photoelectron spectra of fluorene and its analogues, biphenyl, dibenzofuran, carbazole, dibenzothiophene, and phenanthrene were measured and analyzed. The assignment of the π-electron ionizations using orbital interaction and symmetry arguments for the constituent parts of the molecules indicates that the energy levels of the fluorene analogues can be reproduced within a few percent of error. A close linear correlation between the π-ionization energies and the eigenvalues of the corresponding HMO-orbitals is obtained as well.

The effect of ortho substituents NH2, OCH3, CH3, Cl and NO2 on the fragmentation of five symmetrically and five unsymmetrically 2,2′-disubstituted stilbenes under electron impact was investigated. The fragmentation patterns deduced were supported by metastable transitions in the first and second field free regions and by exact mass measurements of prominent ions. In general, the fragmentation was found to be in accord with that of stilbene and the corresponding monosubstituted stilbenes. There are, however, some deviations from the general fragmentation scheme caused by direct through-space interactions of the ortho, ortho′ substituents with concomitant loss of neutral fragments. It is supposed that the formation of 7-membered cyclic or heterocyclic ions is the result of such through-space reactions.

The Hel and Hell photoelectron spectra of the title compounds have been recorded and an­ alysed on the basis of comparison with chlorotrifluoromethane and methyl halides. Spin-orbit splitting could be observed in the ground state of CF3I+ where it amounts to 0.73 eV and is unresolved in CF3Br+. Vibrational fine structure observed in two band systems D and E in CF3Br+, and X and E in CF3I+ is also discussed.

The electron impact induced fragmentation of 1,3-diphenyl-2-pyrazoline was studied by nitrogen-15, carbon-13 and deuterium labelling, substitution in the para position of one of the phenyl rings by fluoro and methoxy groups, and ion kinetic energy spectroscopy, as well as accurate mass measurements. In the fragmentation pathway observed all the ions in the mass spectrum of 1,3-diphenyl-2-pyrazoline (except m/e 103) originate from the molecular ion, which in all compounds is the base peak. The formation of prominent fragment ions is discussed.

The UV photoelectron spectra of 21 halogen (chloro- bromo- and iodo ) -substituted thiophenes have been studied. The assignment was based on band shapes, correlation of band positions of related compounds and CNDO/S calculations. In the case of compounds bearing iodine in the three and four positions the above considerations gave contradictory results and only the relative intensities in the HeI and HeII spectra provided decisive proof for the assignment. The substituent effect in the α positions differs considerably from that in the β position. To explain these effects a simple conjugative model was proposed. Not only does the achieved assignment fit the correlation along the chloro-bromo-iodo series well, but it also provides a simple method for constructing the electronic structure of polyhalogenated systems from simpler building blocks of molecules with a lower degree of substitution (e.g. the band structure of the tetrachloro derivative from those of 2,5-dichloro- and 3,4-dichloro-thiophenes). This proves that a consistent picture was obtained of the electronic structure of halogen thiophenes.

The electronic structure and conformation in the gas phase of N-benzylideneaniline, its para-nitro and -methoxy as well as the ring perfluorinated derivatives were investigated by photoelectron (PE) spectroscopy and semiempirical molecular orbital (HMO) calculations. The π-ionizations were assigned and it is shown that these compounds in the gas phase are in a nonplanar conformation.

The complex photoelectron spectrum of the B state of N2O+ has been remeasured at high resolution and a novel model proposed to interpret the improved data. In the model, a progression of variable strength Fermi resonances is postulated to occur between pairs of vibrational subbands that differ by ν3−2ν2−(2v−1)x33 rather than between members of the usual overtone progression. The model is seen to accurately describe the experimental data.

The vacuum ultraviolet absorption spectrum of trans‐dibromoethylene is reported. Most of the extensive structure is assigned to four different Rydberg series, one of which converges on the first ionization limit, two of which converge on the second ionization limit and one of which converges on the fourth ionization limit. Much of the vibrational fine structure is associated with the first Rydberg series. The discussion focuses on the geometries of Rydberg and corresponding cationic states, on some aspects of the series fitting procedures, on the meaning of quantum defect values, and on selection rules.

Les parametres energetiques du transfert d'electrons pour une serie d'alkylbenzenes substitues sont mesures en solution et en phase gazeuse. Les potentiels d'oxydation standards E Ar 0 sont obtenus a partir de voltammogrammes cycliques reversibles dans l'acide fluorhydrique en presence d'electrodes microvoltammetriques. Les valeurs obtenues sont en bonne correlation avec les potentiels d'ionisation des hydrocarbures aromatiques en phase gazeuse. Cas aussi, des polyalkylbenzenes. Donnees, de plus, sur les hydrocarbures aromatiques complexes π au chrome tricarbonyle

The coupling of electronic and nuclear motions in the rovibronic levels of the lowest Rydberg states of methyl iodide is discussed in terms of a frame transformation between lab- and body- frame coordinate systems for an s Rydberg electron in the field of an electronically-degenerate, symmetric-top molecular ion core. It is shown that the r-dependence of exchange, spin-orbit, spin-rotation, and vibronic interactions, where r is the radial distance of the electron from the ion core, must be considered in order to provide a consistent analysis of the experimental data. Molecular constants, obtained by fitting one- and two-photon absorption spectra, show conclusively that the spin of the Rydberg electron is uncoupled from the molecular frame. Bandshape fitting reveals that the interaction between electronic and vibrational angular momenta leads to complete angular momentum quenching in some vibronic levels, in which it appears that the vibrating core "traps" the Rydberg electron. constants permit extrapolation of channel mixing across ionization thresholds in CH3I but not in HI. discussion of these events is sketched. The magnitudes of the B rotational A theoretical frame for the

Hybridization in spiro[2,4]hepta-4,6-diene (I), spiro[2,4]hepta-2,4,6-triene (II) and spiro[4,4]-nona-2,4,6,8-tetraene (III) is considered by applying the method of maximum overlap. The hybrids of the spiro carbon in I and II differ considerably from the sp3-case. The presence of the carbon rings of different size leads to nonequivalent hybrids for the central carbon: sp2·60 and sp3·49 and sp2·58 and sp3·53 for I and II, respectively. The calculated exponents n of the spn-hybrids for CH bonds are correlated with the τ values (chemical shifts) using a previously observed linear correlation τ = 5(n − 1). The reasons for some deviations from the above correlation are discussed.