Development of an in situ dual-channel thermal desorption gas chromatography instrument for consistent quantification of volatile, intermediate-volatility and semivolatile organic compounds

Aerosols are a source of great uncertainty in radiative forcing predictions and have poorly understood health impacts. Most aerosol mass is formed in the atmosphere from reactive gas-phase organic precursors, forming secondary organic aerosol (SOA). Semivolatile organic compounds (SVOCs) (effective saturation concentration, C*, of 10−1–103 µg m−3) comprise a large fraction of organic aerosol, while intermediate-volatility organic compounds (IVOCs) (C* of 103–106 µg m−3) and volatile organic compounds (VOCs) (C* ≥ 106 µg m−3) are gas-phase precursors to SOA and ozone. The Comprehensive Thermal Desorption Aerosol Gas Chromatograph (cTAG) is the first single instrument simultaneously quantitative for a broad range of compound-specific VOCs, IVOCs and SVOCs. cTAG is a two-channel instrument which measures concentrations of C5–C16 alkane-equivalent-volatility VOCs and IVOCs on one channel and C14–C32 SVOCs on the other coupled to a single high-resolution time-of-flight mass spectrometer, achieving consistent quantification across 15 orders of magnitude of vapor pressure. cTAG obtains concentrations hourly and gas–particle partitioning for SVOCs every other hour, enabling observation of the evolution of these species through oxidation and partitioning into the particle phase. Online derivatization for the SVOC channel enables detection of more polar and oxidized species. In this work we present design details and data evaluating key parameters of instrument performance such as I/VOC collector design optimization, linearity and reproducibility of calibration curves obtained using a custom liquid evaporation system for I/VOCs and the effect of an ozone removal filter on instrument performance. Example timelines of precursors with secondary products are shown, and analysis of a subset of compounds detectable by cTAG demonstrates some of the analytical possibilities with this instrument.

Instrument performance self-efficacy perceptions of Music education students

The aim of this research was to identify the instrument performance self-efficacy status of students in the music education department. The study group for the research comprised 121 students attending Mehmet Akif Ersoy University Faculty of Education, Department of Music Education. In order to identify the self-efficacy perceptions of students in the research, the “Self-Efficacy Scale Related to Instrument Performance” developed by Şeker (2016) was used. The model had a chi-square value 283.52, with 148 degrees of freedom. Investigation of the reliability of the scale found that the Cronbach alpha coefficient for the whole scale was .90 with correlation coefficient r= .88, p<0.01. When the instrument performance self-efficacy of students in the music education department was investigated, it was seen that male students have higher self-efficacy perception than female students. Additionally, students who had graduated from fine art high schools were surmised to have higher self-efficacy for instrument performance compared to those who had graduated from other high schools. Keywords: Instrument performance; music education; self-efficacy.

Development of an In Situ Dual-Channel Thermal Desorption Gas Chromatography Instrument for Consistent Quantification of Volatile, Intermediate Volatility and Semivolatile Organic Compounds

Aerosols are a source of great uncertainty in radiative forcing predictions and have poorly understood health impacts. Most aerosol mass is formed in the atmosphere from reactive gas phase organic precursors, forming secondary organic aerosol (SOA). Semivolatile organic compounds (SVOCs) (effective saturation concentration, C*, of 10−1–103 μg m−3) comprise a large fraction of organic aerosol, while intermediate volatility organic compounds (IVOCs) (C* of 103–106 μg m−3) and volatile organic compounds (VOCs) (C* ≥ 106 μg m−3) are gas phase precursors to SOA and ozone. The Comprehensive Thermal Desorption Aerosol Gas Chromatograph (cTAG) is the first single instrument simultaneously quantitative for a broad range of compound-specific VOCs, IVOCs and SVOCs. cTAG is a two-channel instrument which measures concentrations of C5–C16 alkane equivalent volatility VOCs and IVOCs on one channel and C14–C32 SVOCs on the other coupled to a single High Resolution Time of Flight Mass Spectrometer, achieving consistent quantification across 15 orders of magnitude of vapor pressure. cTAG obtains concentrations hourly and gas–particle partitioning for SVOCs bihourly, enabling observation of the evolution of these species through oxidation and partitioning into the particle phase. Online derivatization for the SVOC channel enables detection of more polar and oxidized species. In this work we present design details and data evaluating key parameters of instrument performance such as I/VOC collector design optimization, linearity and reproducibility of calibration curves obtained using a custom liquid evaporation system for I/VOCs and the effect of an ozone removal filter on instrument performance. Example timelines of precursors with secondary products are shown and analysis of a subset of compounds detectable by cTAG demonstrates some of the analytical possibilities with this instrument.

Pengembangan Instrumen Penilaian Autentik Pada Materi Eksositem di SMA

This study aims to develop an authentic assessment instrument on ecosystem material for SMA using the 4D type development model (Define, Design, Develop, Disseminate) by Thiagarajan. The trial was carried out at SMA Negeri 1 Bulukumba in class X MIA 1. The results of expert validation showed that the project appraisal instrument, performance and lesson plans had a strong relevance with the value of V = 88%, 100% and 100% respectively where all three were greater than 75% that it fulfilled the content validity coefficient. The reliability test was carried out at the trial stage by analyzing the results of the teacher's assessment of students using developed instruments. The result of the reliability test shows the value of r11 = 0.943 or greater than 0.70 so that it can be stated that the instrument developed is valid and reliable.Keywords: development, authentic assessment, validation

Theoretical and methodological basis of music education: structure and contents

The research subject of the article is the theoretical and methodological basis of music education represented in a traditional four-level structure (developed by A. Yudin within the system approach), consisting of: 1) a philosophical, 2) a general scientific, 3) a specific scientific, 4) a methodological level. Based on the thesis about the connection between theory and practice in music education, the second part of the article briefly describes the contents of the first three levels of the structure of the theoretical and methodological basis which are believed to be the most academical. The author focuses on two aspects: 1. The goals and potentials of the level under consideration; 2. The problems arising at each level. The author arrives at the following conclusions: 1) the philosophical level of the theoretical and methodological basis of music education, being the most general and therefore the leading one, is necessary for training prospective musicians for the formation of the value, moral and spiritual, and esthetic components of education; 2) the general scientific level helps systematize the philosophic provisions and concepts into certain approaches and principles which can be introduced into the pedagogical practice as models of integral formation of education processes; 3) the level of socio-scientific disciplines, which is the most thoroughly developed due to the close connection with practical aspects and problems, consists in the aspects of the contents of education (musicology), the methodology of teaching (pedagogics), and the study subject/instrument (performance art).&nbsp; &nbsp;