The recent technological advances in environmental monitoring coupled with the increasingly stringent effluent requirements being placed on waste treatment systems makes it vital to have a more complete understanding of how specific compounds in waste streams can impact wastewater treatment processes. Since activated sludge processes are recognized as one of the most often applied technologies in wastewater treatment, this study assesses the impacts of select toxic synthetic organic compounds (SOCs) on the activated sludge communities in two types of wastewater treatment reactors: a completely-mixed activated sludge reactor (CMAS) and a sequencing batch reactor (SBR). Commonly applied activated sludge monitoring parameters, such as solids analysis and substrate removal, are collected and correlated to the results of microscopic image analysis (IA) and direct gradient gel electrophoresis (DGGE) to monitor the response of the activated sludge communities to variations in operational conditions, including the incorporation of SOCs in the influent feed and varying the solids retention time. The results of this research indicate that the response of the activated community is highly dependent on the reactor configuration. The CMAS settling performance was more strongly correlated to the shape parameters, and the SBR settling performance was more strongly correlated to the size parameters, which is qualitatively supported by particle settling theory when considering that SBR flocs were found to be larger than the CMAS flocs. The SBR began to exhibit larger floc sizes and had a higher sludge volume index with the incorporation of SOCs, while the CMAS flocs became more spherical after SOCs were incorporated and exhibited more discrete settling. The molecular analysis results revealed that the community structure within the activated sludge system was transient in response to environmental variations. Banding patterns indicated that samples were more similar to other samples taken from the same reactor under the same operational conditions. Thus, as operational conditions were varied, sample banding patterns would also change, indicating transitions in the genetic composition, and ultimately the dominant species present, in response to environmental changes.

This study aimed to explore the integration of varying angles in small-scale measurements and assess the light transmission performance of uncoated curtains. A total of four curtains were evaluated: blackout curtain samples 1 and 2 had a weft satin structure, while daytime curtain samples 3 and 4 consisted of a twill structure. The primary challenge was the inadequacy of a standardized test method for measuring the blackout effect, which led to inefficiencies and resource consumption for Company X. To address this, the study emphasized the need to investigate and establish a reliable and efficient evaluation method for uncoated curtains. By developing a standardized test method, it is possible to reduce waste material, labor costs, and resource consumption, enabling companies to operate more efficiently, sustainably, and responsibly. In the pursuit of understanding the blackout effect and evaluating the structural parameters of uncoated curtains, this study explored various test methods and parameters. More specifically, parameters such as air permeability, porosity, and thickness together with microscopic evaluation, were investigated to shed light on their influence on light transmission. The voids in the fabric were found to be a significant factor, along with porosity and air permeability, which demonstrated a correlation with lower values for the blackout curtains. The construction of the test method in a small-scale required a controlled space in the form of a lightbox. Light proofing of the box was required and successfully achieved in Prototype 1 using plywood, sealing strips, and fixtures, resulting in a lower lux value compared with the previous internal method. Objective measurements using the Konica CL-500A lux meter provided a repeatable and reliable test method with a lower tolerance value of 0,05 lx. The developed test method, theoretical Prototype 2, incorporates different sun angles by adjusting the curtain’s position, in the angles of 0°, 15°, 30°, 45° and 60°, and the rotation of the sample within 0° to 360° in intervals of 45°. The important parameters of weft density and the subsequent increase in weight were key factors in the results of light transmission, air permeability, and porosity. Furthermore, properties of the uncoated curtains such of continuous filaments and darker color showed a higher blackout effect. After the identification of complications with the lamp used in the measurement, there has been a focus on discussing the significance of a light diffuser. Additionally, alternative approaches to measure light transmission have been presented, such as digital image analysis and air permeability.