Application of multi-group cfa in analysing moderation effect of socioeconomic attributes on public housing performance

This study analysed moderation effect of socioeconomic attributes of income and education on public housing performance model using the multi-group confirmatory factor analysis (CFA) method. The objectives of the study was to evaluate the influence of socioeconomic attributes of income and education on public housing performance using occupants’ experience, with a view to proffer recommendations on objective indicator of public housing performance. Literature revealed how little attention is given to effects of socioeconomic attributes on building performance in post occupancy evaluation (POE). This leads to misuse of resources in facilities management. Sample households of 350 were selected in Gombe metropolis, Nigeria, by systematic random sampling to answer questionnaires as the major instrument of data collection. SPSS Version 22 was used for preliminary analyses and AMOS version 21 was used to validate the constructs and develop Structural Equation Model (SEM) of building performance. Results indicated an acceptable SEM model for use in building performance evaluation, with all factor loadings above 0.5 and required fitness indexes achieved. Moderation effect of occupants’ education and income were proved not significant on their experience responses. The finding portrayed occupants’ experience as objective tool for measuring building performance Implication of this finding is in supporting the notion that experience is objective medium of measuring performance than satisfaction. Hence, scholars and professionals in housing should be cautious of the use of these terminologies interchangeably

Efficiency and degradation products elucidation of the photodegradation of mefenpyrdiethyl in water interface using TiO₂ P-25 and Hombikat UV100.

The photodegradation of mefenpyrdiethyl (MFD), an herbicide safener, was investigated in aqueous suspensions by using Degussa P-25 and Hombikat UV100 titanium oxide under simulated sunlight irradiation. The effects of initial concentration of the herbicide, pH, catalysts and hydrogen peroxide doses as well as their combinations were studied and optimized. Accordingly, the kinetic parameters were determined and the effectiveness of the processes was assessed by calculating the rate constants. A pseudo first-order kinetics was observed. Under experimental conditions, the degradation rate constants were strongly influenced using P-25 and no noticeable effect was observed for Hombikat UV100. DFT calculations with B3LYP/6-311+G(2d,p)//B3LYP/6-31+G(d,p) level of theory were performed to check whether significant conformational changes occur when the charge state of the MFD substrate changes and whether these changes could play a role in the dependency of photodegradation rate constant on the studied pH. High resolution mass spectrometry (FT-ICR/MS) was implemented to identify the main degradation products

Analysis of the unresolved organic fraction in atmospheric aerosols with ultrahigh-resolution mass spectrometry and nuclear magnetic resonance spectroscopy: Organosulfates as photochemical smog constituents.

Complementary molecular and atomic signatures obtained from Fourier transform ion cyclotron resonance (FTICR) mass spectra and NMR spectra provided unequivocal attribution of CHO, CHNO, CHOS, and CHNOS molecular series in secondary organic aerosols (SOA) and high-resolution definition of carbon chemical environments. Sulfate esters were confirmed as major players in SOA formation and as major constituents of its water-soluble fraction (WSOC). Elevated concentrations of SO(2), sulfate, and photochemical activity were shown to increase the proportion of SOA sulfur-containing compounds. Sulfonation of CHO precursors by means of heterogeneous reactions between carbonyl derivatives and sulfuric acid in gas-phase photoreactions was proposed as a likely formation mechanism of CHOS molecules. In addition, photochemistry induced oligomerization processes of CHOS molecules. Methylesters found in methanolic extracts of a SOA subjected to strong photochemical exposure were considered secondary products derived from sulfate esters by methanolysis. The relative abundance of nitrogen-containing compounds (CHNO and CHNOS series) appeared rather dependent on local effects such as biomass burning. Extensive aliphatic branching and disruption of extended NMR spin-systems by carbonyl derivatives and other heteroatoms were the most significant structural motifs in SOA. The presence of heteroatoms in elevated oxidation states suggests a clearly different SOA formation trajectory in comparison with established terrestrial and aqueous natural organic matter

High molecular diversity of extraterrestrial organic matter in Murchison meteorite revealed 40 years after its fall

Numerous descriptions of organic molecules present in the Murchison meteorite have improved our understanding of the early interstellar chemistry that operated at or just before the birth of our solar system. However, all molecular analyses were so far targeted toward selected classes of compounds with a particular emphasis on biologically active components in the context of prebiotic chemistry. Here we demonstrate that a nontargeted ultrahigh-resolution molecular analysis of the solvent-accessible organic fraction of Murchison extracted under mild conditions allows one to extend its indigenous chemical diversity to tens of thousands of different molecular compositions and likely millions of diverse structures. This molecular complexity, which provides hints on heteroatoms chronological assembly, suggests that the extraterrestrial chemodiversity is high compared to terrestrial relevant biological- and biogeochemical-driven chemical space