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A research project submitted in partial fulfilment of the requirements for the degree of MA by coursework and Research Report in the field of Organisational Psychology in the Faculty of Humanities. University of the Witwatersrand, Johannesburg. March 2016 / There is international growing evidence to support the notion that indoor planters positively impact employees’ emotional states, personal health, work engagement as well as their overall perceptions of their work environment and ultimately impacting employee productivity. However this ground-breaking research has never been conducted within a South African Work Environment. Consequently the following study adopts a quasi-experimental study in order to investigate the impact that indoor plants may have on employee physical well-being, psychological well-being, work engagement and their overall perception of their work environment. Furthermore, the researcher aimed to assess whether the employees connectedness to nature influenced the impact the plants had on them, thus assessing how this covariate may impact the relationship between the absence and presence of plants and the above mentioned dependent variables. A Sample of 32 Global Service Management Centre (GSMC) employees from an internationally recognised organisation, Business Connexion, were assessed over a period of 12 weeks. The first assessment was conducted in the no plant condition, while the final assessment was conducted once the plants were installed in the whole office area. Additionally, SE Controls were positioned throughout the office area in order to measure the fluctuations of the air quality once the planters were installed. The results of a series of Wilcoxon Sign Rank Tests as well as Spearman’s Rank Order Correlations indicated no significant results; however upon closer evaluations of the individual scale items the researcher identified several statistically significant results that were unpacked and discussed. The readings from the SE Controls indicated either an improvement or stabalisation of the air quality variables that were being assessed in the current study. / GR2017

A research project submitted in partial fulfilment of the requirements for the degree of MA by coursework and Research Report in the field of Industrial Psychology in the Faculty of Humanities. University of the Witwatersrand, Johannesburg. February/May 2017 / Much evidence exists with regard to indoor plants and their positive effect on psychological perceptions as well as environmental air quality. However, this type of research has only ever been conducted once in a South African setting, which can be argued, is different to international contexts, in terms of climate and financial status. Indoor plants and their positive effects may have monumental effects on employees. This research assessed the presence of plants, on a sample of 34 employees at Discovery VitalityLife, consisting of Human Resources workers and call centre agents, on psychological perceptions (work engagement; psychological well-being; physical well-being and aesthetics) and on environmental factors (Total Volatile Organic Compounds; Benzene; Xylene; Carbon Dioxide (CO2); temperature and relative humidity). This research was conducted over a period of approximately three months whereby at Time 1 plants were absent and Time 2 plants were present. The same questionnaires were administered at both times. So too were Volatile Organic Compounds measured weekly and three measurement devices were installed in the workplace taking measurements of CO2, humidity, and indoor temperature every hour. The results found were that there were no statistically significant differences for the psychological perceptions from Time 1 to Time 2. This was concluded to be a result of the context in which this research took place. Total Volatile Organic Compounds, Benzene and relative humidity levels statistically significantly decreased at Time 2. Xylene levels statistically significantly increased at Time 2. There was no evidence to suggest statistically significant differences for CO2 and temperature from Time 1 to Time 2. / MT2018

by Hei Yuk Kwan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 81-87). / Abstract also in Chinese. / ABSTRACT --- p.i / DECLARATION --- p.ii / ACKNOWLEDGEMENT --- p.iii / TABLE OF CONTENTS --- p.iv / LIST OF TABLES --- p.vi / LIST OF FIGURES --- p.vii / Chapter CHAPTER ONE : --- INTRODUCTION --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.1.1. --- Volatile Organic Compounds --- p.1 / Chapter 1.1.2. --- Photocatalytic Oxidation --- p.2 / Chapter 1.1.3. --- Adsorption --- p.4 / Chapter 1.2. --- Scope of Work --- p.8 / Chapter CHAPTER TWO : --- PHOTOCATALYSIS --- p.10 / Chapter 2.1 --- Fundamental --- p.10 / Chapter 2.2. --- Experimental --- p.14 / Chapter 2.2.1. --- Materials --- p.14 / Chapter 2.2.2. --- Instruments --- p.14 / Chapter 2.2.3. --- Experimental Conditions --- p.19 / Chapter 2.2.4. --- Procedure --- p.20 / Chapter 2.3. --- Results and Discussion --- p.28 / Chapter 2.3.1. --- Photocatalytic Degradation of DCE --- p.28 / Chapter 2.3.2. --- Photocatalytic Degradation of TCE --- p.31 / Chapter 2.3.3. --- Photocatalytic Degradation of DCE and TCE Binary System --- p.34 / Chapter 2.3.4. --- Photocatalytic Degradation of Ethyl Acetate --- p.39 / Chapter 2.3.5. --- Photocatalytic Degradation of Methyl Isopropyl Ketone --- p.41 / Chapter 2.3.6. --- Photocatalytic Degradation of Ethyl Acetate and Methyl Isopropyl Ketone Binary System --- p.43 / Chapter CHAPTER THREE : --- ADSORPTION --- p.47 / Chapter 3.1. --- Fundamental --- p.47 / Chapter 3.1.1. --- Mordenite --- p.51 / Chapter 3.1.2. --- Activated Carbon --- p.55 / Chapter 3.2. --- Experimental --- p.58 / Chapter 3.2.1. --- Materials --- p.58 / Chapter 3.2.2. --- Instrument --- p.59 / Chapter 3.2.3. --- Procedure --- p.60 / Chapter 3.3. --- Results and Discussion --- p.65 / Chapter 3.4. --- "Adsorption Isotherm of 1,3,5-trimethylbenzene on Mordenite in Aqueous Phase" --- p.70 / Chapter 3.5. --- "Thermal Regeneration of 1,3,5-trimethylbenzene on Mordenite in Aqueous Phase" --- p.72 / Chapter CHAPTER FOUR : --- CONCLUSION --- p.79 / REFERENCES --- p.81

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A research project submitted in partial fulfillment of the requirements for the degree of MA by coursework and Research Report in the field of Organisational Psychology in the Faculty of Humanities. University of the Witwatersrand, Johannesburg, November 2017 / The current study utilized the Attention Restoration Theory to investigate whether plants in an office context produced restorative effects that enable employees to perform better. The Attention Restoration Theory asserts that individuals will experience increased concentration after spending time in or viewing nature. This study was one of the first attempts to empirically investigate the effect of indoor plants on experiences of performance outcomes and perceptions of Indoor Environmental Quality (IEQ) within South Africa. The researcher aimed to assess whether the individual’s nature identity moderated the impact of the plants. Most previous studies on the outcomes of indoor plants have been conducted in Western, Northern hemisphere contexts. In this experimental study, 120 participants were randomly assigned to one of three conditions: (1) no plants or pictures of plants; (2) only plants; (3) only canvas pictures of plants. The rooms were identical in every other respect. Participants completed two tasks (a card-sorting task and a reading task) and two questionnaires, namely the connectedness to nature scale to assess participant’s nature identity and a previously developed questionnaire that aimed to assess task performance. Additionally, SE controls IEQ monitors were positioned in each office to measure fluctuations of air quality (i.e. temperature, humidity and carbon dioxide levels) in order to assess IEQ. The results from a series of ANOVA’s demonstrated a reduction in participants’ errors (F (2, 117) = 7.137, p = 0.001), a positive reaction to the given task (F (2, 117) = 8.904, p = 0.000), as well as a reduction in participants’ task completion time (F (2, 117) = 43.422, p = 0.000) in the plants condition. These results demonstrated a statistically significant effect on performance in the presence of plants as well as an improvement in air quality through a reduction of carbon dioxide (F (2, 117) = 6.429, p = 0.000). The results revealed that the plants condition was statistically significantly different from that of the pictures of plants and the control condition with regards to the performance outcomes. The result from the two-way ANOVA’s demonstrated that nature identity did not moderate the above relationships (Errors: F (1, 114) = 2.060, p = 0.132; Completion time: F (1, 114) = 0.967, p = 0.383; Reaction to the task: F (1, 114) = 0.017, p = 0.983). This study enhances knowledge regarding indoor plants within the South African context as well as practically influencing working environments where employees are expected to be productive. / MT 2019

Experiments were conducted to determine the photocatalytic degradation of three types of gas-phase compounds, NOX, VOCs, and chloramines, by TiO2 impregnated tiles. The oxides of nitrogen NO and NO2 (NOx) have a variety of negative impacts on human and environmental health ranging from serving as key precursors for the respiratory irritant ozone, to forming nitric acid, which is a primary component of acid rain. A flow tube reactor was designed for the experiments that allowed the UV illumination of the tiles under exposure to both NO and NO2 concentrations in simulated ambient air. The reactor was also used to assess NOx degradation for sampled ambient air. The PV values for NO and NO2 were 0.016 cm s-1 and 0.0015 cm s-1, respectively. For ambient experiments a decrease in ambient NOx of ~ 40% was observed over a period of roughly 5 days. The mean PV for NOx for ambient air was 0.016 cm s-1 and the maximum PV was .038 cm s-1. Overall, the results indicate that laboratory conditions generally simulate the efficiency of removing NOx by TiO2 impregnated tiles. Volatile organic compounds (VOC's) are formed in a variety of indoor environments, and can lead to respiratory problems (US EPA, 2010). The experiments determined the photocatalytic degradation of formaldehyde and methanol, two common VOCs, by TiO2 impregnated tiles. The same flow tube reactor used for the previous NOX experiments was used to test a standardized gas-phase concentration of formaldehyde and methanol. The extended UV illumination of the tiles resulted in a 50 % reduction in formaldehyde, and a 68% reduction in methanol. The deposition velocities (or the photocatalytic velocities, PV) were estimated for both VOC's. The PV for formaldehyde was 0.021 cm s-1, and the PV for methanol was 0.026 cm s-1. These PV values are slightly higher than the mean value determined for NO from the previous experiments which was 0.016 cm s-1. The results suggest that the TiO2 tiles could effectively reduce specific VOC levels in indoor environments. Chlorination is a widespread form of water disinfection. However, chlorine can produce unwanted disinfection byproducts when chlorine reacts with nitrogen containing compounds or other organics. The reaction of chlorine with ammonia produces one of three chloramines, (mono-, di-, and tri-chloramine). The production of chloramines compounds in indoor areas increases the likelihood of asthma in pool professionals, competitive swimmers, and children that frequently bath in indoor chlorinated swimming pools (Jacobs, 2007; Nemery, 2002; Zwiener, 2007). A modified flow tube reactor in conjunction with a standardized solution of monochloramine, NH2Cl, determined the photocatalytic reactions over the TiO2 tiles and seven concrete samples. The concrete samples included five different concrete types, and contained either 5 % or 15 % TiO2 by weight. The PV for the tiles was 0.045 cm s-1 for the tiles manufactured by TOTO Inc. The highest PV from the concrete samples was 0.054 cm s-1. Overall the commercial tiles were most efficient at reducing NH2Cl, compared to NOX and VOC compounds. However, the concrete samples had an even higher PV for NH2Cl than the tiles. The reason for this is unknown; however, distinct surface characteristics and a higher concentration of TiO2 in the concrete may have contributed to these findings.

Metal-Organic Frameworks (MOFs) are three-dimensional porous nanomaterials with a variety of applications, including catalysis, gas storage and separation, and sustainable energy. Their potential as air filtration systems is of interest for designer carbon capture materials. The chemical constituents (i.e. organic ligands) can be functionalized to create rationally designed CO2 sequestration platforms, for example. Hardware and software alike at the bleeding edge of supercomputing are utilized for designing first principles-based molecular models for the simulation of gas sorption in these frameworks. The classical potentials developed herein are named PHAST -- Potentials with High Accuracy, Speed, and Transferability, and thus are designed via a "bottom-up" approach. Specifically, models for N2 and CH4 are constructed and presented. Extensive verification and validation leads to insights and range of applicability. Through this experience, the PHAST models are improved upon further to be more applicable in heterogeneous environments. Given this, the models are applied to reproducing high level ab initio energies for gas sorption trajectories of helium atoms in a variety of rare-gas clusters, the geometries of which being representative of sorption-like environments commonly encountered in a porous nanomaterial. This work seeks to push forward the state of classical and first principles materials modeling. Additionally, the characterization of a new type of tunable radical metal--carbene is presented. Here, a cobalt(II)--porphyrin complex, [Co(Por)], was investigated to understand its role as an effective catalyst in stereoselective cyclopropanation of a diazoacetate reagent. Density functional theory along with natural bond order analysis and charge decomposition analysis gave insight into the electronics of the catalytic intermediate. The bonding pattern unveiled a new class of radical metal--carbene complex, with a doublet cobalt into which a triplet carbene sigma donates, and subsequent back-bonding occurs into a pi* antibonding orbital. This is a different type of interaction not seen in the three existing classes of metal-carbene complexes, namely Fischer, Schrock, and Grubbs. Finally, the virtual engineering of enhanced chemical warfare agent (CWA) detection systems is discussed. As part of a U.S. Department of Defense supported research project, in silico chemical modifications to a previously synthesized zinc-porphyrin, ZnCS1, were made to attempt to achieve preferential binding of the nerve agent sarin versus its simulant, DIMP (diisopropyl methylphosphonate). Upon modification, a combination of steric effects and induced hydrogen bonding allowed for the selective binding of sarin. The success of this work demonstrates the role that high performance computing can play in national security research, without the associated costs and high security required for experimentation.

In the U.S. and other developed countries, humans spend the vast majority of their time within the built environment. As a result, a substantial portion of our collective exposure to airborne pollutants, even those of outdoor origin, occurs in indoor environments. In addition, building construction materials and operational practices are changing as we endeavor to reduce the energy burden of the built environment. These changes result in barriers and opportunities in mitigating exposure to indoor pollutants and the accompanying implications for human health. This dissertation advances knowledge regarding low-energy control of indoor ozone. Ozone is often considered a pollutant of outdoor concern. However, ozone in indoor environments presents important challenges regarding exposure, intake, and chemistry in the built environment. The investigations in this dissertation extend the state understanding of indoor transport and transformation of ozone, and the potential for using material-surface interactions in buildings to suppress concentrations of indoor ozone. The first objective relates to the determination of magnitudes of ozone removal and product emissions at room or building scales. This objective provides new data on reactive uptake and product generation in large-scale environments, develops Monte Carlo models describing indoor ozone removal by materials in homes, and compares active and passive methods of indoor ozone removal. The second objective addresses the need to develop improved air cleaning materials through experiments and modeling that address material-ozone reactions in porous materials. This objective advances the state of modeling heterogeneous reactive uptake of ozone by characterizing material physical properties and transport phenomena, determining their impact on ozone removal, and using these data to develop a more mechanistic model of material-ozone reactions. Ultimately, these investigations advance the engineering concepts that support the development of passive indoor pollutant controls, an important tool for reducing concentrations of indoor pollutants while supporting low-energy building initiatives. The combination of experimental characterization of ozone deposition velocities and product emission rates, whole-building Monte Carlo modeling, and mechanistic material/pollutant models provide important new data and approaches that expand the state of knowledge of the fate and transport of reactive pollutants in indoor environments. / text