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The approach that students take in their studies at university is critical not only for their academic success but is equally important in life-long learning for their career and professional development. Cognitive science has demonstrated that retesting oneself on material when learning enhances and promotes greater retention of knowledge compared to rereading the material. Learning that is spaced out over multiple study sessions also allows for greater retention of knowledge in the longer-term compared to "cramming" of information. A survey study with first- and second-year undergraduate students (n = 135) at a university in Spain and in the U.K. was carried out to investigate the study strategies and habits prevalent in these cohorts and to explore the extent of their metacognitive awareness. It was found that most students endorsed self-testing but also suboptimal study methods such as rereading, copying notes, and cramming. There was evidence of differences between the U.K. and Spain in relation to decisions for prioritizing studying, returning to review course material, and time of study. A key conclusion is the need to embed and emphasize effective strategies for learning into curricula and for faculty to have metacognitive awareness in their teaching.

Educational buildings tend to fail in the contagion containment of airborne infectious diseases because of the high number of children, for several hours a day, inside enclosed environments that often have inadequate indoor air quality (IAQ) conditions. This study aimed to assess indoor environmental quality and test the effectiveness of portable air cleaners (PACs) in alleviating airborne particle levels in schools of Central–Southern Spain during the period of reopening after the lockdown due to the COVID-19 outbreak. To accomplish this, three sampling campaigns were organized from September to December 2020 to consistently monitor temperature and relative humidity, carbon dioxide, and particulate matter in nineteen classrooms (seven school buildings). Results showed that although the recommendation of maintaining the windows open throughout the day seemed to be effective in promoting, in general, proper ventilation conditions (based on CO2 levels). For the colder campaigns, this practice caused notorious thermal comfort impairment. In addition, a great number of the surveyed classrooms presented levels of PM2.5 and PM10, attributable to outdoor and indoor sources, which exceeded the current WHO guideline values. Moreover, considering the practice of having the windows opened, the installation of 1 unit of PACs per classroom was insufficient to ensure a reduction in particle concentration to safe levels. Importantly, it was also found that children of different ages at different education levels can be exposed to significantly different environmental conditions in their classrooms; thus, the corrective measures to employ in each individual educational setting should reflect the features and needs of the target space/building. [ABSTRACT FROM AUTHOR]

An environmental research project was carried out by a consortium established among scientists and university lecturers in collaboration with two high schools. High school students participated in a long-term study of the local temporal profiles of tropospheric ozone and the relationship to pollution and meteorological parameters. Low-cost research facilities for the high schools were obtained from public funds. The experimental setup provided a continuous source of data that was followed by the students under the supervision of the teachers. The participation was multidisciplinary (across various classes) and included activities related to the atmospheric study. The experience was motivating for students, providing them with a practical contact with science and the university. (Contains 2 notes, 1 table and 3 figures.)

The role of temperature and low pressure in the reactions of the nitrate radical (NO3) with cyclic alkenes such as cyclopentene, cyclohexene and cycloheptene, have been studied by using a fast flow system with LIF detection of NO3. Results indicate a different reactivity for the reactions of NO3 with cyclic compounds with an exocyclic double bond than for cycloalkenes 1-methyl substituted. This phenomenon may result from the degree of substitution since the size of the member rings has no effect on the reactivity.

Absolute rate coefficient measurements were performed for the Cl atom reaction with a series of esters at room temperature and in the pressure range 15-60 Torr by applying the laser photolysis-resonance fluorescence method. The reactivity of Cl with the investigated esters can be compared with the reactivity of OH radicals with the same esters. The Cl and OH reaction rate coefficients indicated similar trends with the number of carbon atoms and the branching in the esters as was shown for Cl and OH reactions with alkanes.

The reactions of Cl with a series of linear thiols: 1-propanethiol (k1), 1-butanethiol (k2), and 1-pentanethiol (k3) were investigated as a function of temperature (in the range of 268–379 K) and pressure (in the range of 50–200 Torr) by laser photolysis-resonance fluorescence. Only 1-propanethiol has previously been studied, but at 1 Torr of total pressure. The derived Arrhenius expressions obtained using our kinetic data were as follows: k1=(3.97±0.44)×10-11 exp[(410±36)/T], k2=(1.01±0.16)×10-10 exp[(146±23)/T], and k3=(1.28±0.10)×10-10 exp[(129±25)/T] (in units of cm3 molecule-1 s-1). Moreover, a theoretical insight into mechanisms of these reactions has also been pursued through ab initio Möller–Plesset second-order perturbation treatment calculations with 6-311G** basis set. Optimized geometries have been obtained for transition states and molecular complexes appearing along the different reaction pathways. Furthermore, molecular energies have been calculated at QCISD(T) level in order to get an estimation of the activation energies. Finally, the nature of the molecular complexes and transitions states is analyzed by using kinetic-potential and natural bond orbital total energy decomposition schemes. [ABSTRACT FROM AUTHOR]

The reactions of Cl with a series of linear alcohols: methanol (k1), ethanol (k2), 1-propanol (k3), 1-butanol (k4), and 1-pentanol (k5) were investigated as a function of temperature in the range of 264–382 K by laser photolysis-resonance fluorescence. The obtained kinetic data were used to derive the following Arrhenius expressions: k1=(3.55±0.22)×10-10 exp[-(559±40)/T], k2=(5.25±0.52)×10-11 exp[(190±68)/T], k3=(2.63±0.21)×10-11 exp[(525±51)/T], k4=(3.12±0.31)×10-11 exp[(548±65)/T], and k5=(3.97±0.48)×10-11 exp[(533±77)/T] (in units of cm3 molecule-1 s-1). To our knowledge, these are the first absolute kinetic data reported for 1-butanol and 1-pentanol and also the first kinetic study as a function of temperature for these two compounds. Results, mechanism, and tropospheric implications are discussed and compared with the reported reactivity with OH radicals. Moreover, a theoretical insight into the mechanisms of these reactions has also been pursued through ab initio Möller-Plesset second-order perturbation treatment calculations with 6-311G** basis sets. Optimized geometries and vibrational frequencies have been obtained for transition states and molecular complexes appearing along the different reaction pathways. Furthermore, molecular energies have been calculated at quadratic configuration interaction with single, double, and triple excitations level in order to get an estimation of the activation energies. [ABSTRACT FROM AUTHOR]

Various studies have reported that photochemical nucleation of new ultrafine particles (UFP) in urban environments within high insolation regions occurs simultaneously with high ozone (O3). In this work, we evaluate the atmospheric dynamics leading to summer O3 episodes in the Madrid Air Basin (Central Iberia) by means of measuring a 3D distribution of concentrations for both pollutants. To this end, we obtained vertical profiles (up to 1200 m, above ground level) using tethered balloons and miniaturised instrumentation at a suburban site located to the SW of the Madrid Metropolitan Area (MMA), Majadahonda site (MJDH) in July 2016. Simultaneously, measurements of an extensive number of air quality and meteorological parameters were carried out at 3 supersites across the MMA. Furthermore, data from O3-soundings and daily radio-sounding were also used to interpret the atmospheric dynamics. The results demonstrate the concatenation of venting and accumulation episodes, with relative O3 lows (venting) and peaks (accumulation) in surface levels. Regardless of the episode type, fumigation of high altitude O3-rich layers contributes the major proportion of surface O3 concentrations. Accumulation episodes are characterised by a relatively thinner planetary boundary layer (PBL < 1500 m at midday, lower in altitude than the orographic features), low synoptic winds and the development of mountain breezes along the slope of the Guadarrama Mountain Range (W and NW of MMA, maximum altitude > 2400 m). This orographic-meteorological setting causes the vertical recirculation of air masses and the enrichment of O3 in the lower tropospheric layers. When the highly polluted urban plume from Madrid is affected by these dynamics, the highest Ox (O3 + NO2) concentrations are recorded in the MMA. Vertical O3 profiles during venting episodes, with marked synoptic winds and a deepening of the PBL reaching > 2000 m above sea level, were characterised by an upward gradient in O3 levels, whereas low-altitude O3 concentration maxima due to local/regional production were found during the accumulation episodes. The two contributions to O3 surface levels (fumigation from high altitude strata and local/regional production) require very different approaches for policy actions. In contrast to O3 vertical top-down transfer, UFP are formed in the lowest levels and are transferred upwards progressively with the growth of the PBL. [ABSTRACT FROM AUTHOR]

This work presents observations of volatile organic compounds (VOCs), including carbonyls, particulate matter 2.5 (PM2.5) (included in the most recent ambient air quality standards because of its harmful effect on health), PM10 and other important pollutants, CO, SO2, NOx and ozone, over the most industrialized area in the central Iberian Peninsula. Nearly two years of data obtained through a mobile laboratory are used for this purpose. Different concentration ratios and correlations were calculated to assess the effect of the anthropogenic or biogenic processes on the observed VOC levels. The diurnal profile for SO2is different in Puertollano and it does not coincide with the maxima of the other primary pollutants such as benzene, toluene and xylenes (BTX), CO and NO. This behaviour could be attributed to the fact that SO2mainly comes from industrial activities. However, an impact of the industry on air quality was detected not only by the results obtained for SO2, but also by the toluene/benzene, T/B, ratio (7.5). Finally, correlations between meteorological conditions and pollution distribution have been considered; also, the analysis of the back trajectories together with Spearman correlation coefficients have been carried out to understand the origin and pathway in some events with unusual high pollutant values. [ABSTRACT FROM PUBLISHER]