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This paper aims to investigate the optimization of window and shading designs to reduce the building energy consumption of a standard office room while improving occupants' comfort in Tehran and Auckland.

The NSGA-II algorithm, as a multi-objective optimization method, is applied in this study. First, a comparison of the effects of each variable on all objectives in both cities is conducted. Afterwards, the optimal solutions and the most undesirable scenarios for each city are presented for architects and decision-makers to select or avoid.

The results indicate that, in both cities, the number of slats and their distance from the wall are the most influential variables for shading configurations. Additionally, occupants' thermal comfort in Auckland is much better than in Tehran, while the latter city can receive more daylight. Furthermore, the annual energy use in Tehran can be significantly reduced by using a proper shading device and window-to-wall ratio (WWR), while building energy consumption, especially heating, is negligible in Auckland.

To the best of the authors' knowledge, this is the first study that compares the differences in window and shading design between two cities, Tehran and Auckland, with similar latitudes but located in different hemispheres. The outcomes of this study can benefit two groups: firstly, architects and decision-makers can choose an appropriate WWR and shading to enhance building energy efficiency and occupants' comfort. Secondly, researchers who want to study window and shading systems can implement this approach for different climates.

A previous paper had shown that milling organic pigments at elevated temperatures often improves colour development through better wetting. The present investigation shows that heat can, nevertheless, have an overall adverse effect on colour strength and hue of pigments which partially dissolve (and subsequently recrystallise) in a vehicle system under the combined action of heat and impact. Likewise, metastable polymorphic pigments should be dispersed at the lowest possible temperature to minimise hue shifts and/or loss of colour strength.

Application of appropriate shading device strategies in buildings can reduce direct solar heat gain through windows as well as optimize cooling and artificial lighting load. This study investigates the impact of common shading devices such as overhangs, fins, horizontal blinds, vertical blinds and drapes on energy consumption of an office building and suggests energy efficient shading device strategies in the contexts of unique Bangladeshi subtropical monsoon climate.

This research was performed through the energy simulation perspective of a prototype office building using a validated building energy simulation tool eQUEST. Around 100 simulation patterns were created considering various types of shading devices and building orientations. The simulation results were analysed comprehensively to find out energy-efficient shading device strategies.

Optimum overhang and fin height is equal to half of the window height in the context of the subtropical climate of Bangladesh. South and West are the most vulnerable orientations, and application of shading devices on these two orientations shows the highest reduction of cooling load and the lowest increment of lighting load. An existing building was able to save approximately 7.05% annual energy consumption by applying the shading device strategies that were suggested by this study.

The shading device strategies of this study can be incorporated into the Bangladesh National Building Code (BNBC) as new energy-efficient building design strategies because the BNBC does not have any codes or regulations regarding energy-efficient shading device. It can also be used as energy-efficient shading device strategies to other Southeast Asian countries with similar climatic contexts of Bangladesh.

During the dispersion of a pigment in a given application medium, two main processes are taking place side by side. These are the wetting of the pigment surface by the binder components, and the actual dispersion process, i.e. the separation of agglomerates into primary particles or at least into smaller agglomerates by the application of mechanical energy.

Energy codes for residential buildings in India prescribe design guidelines for each climate zone. However, these guidelines are broad and similar for different cities under the same zone overlooking climatic variations due to altitude, location and other geographical factors.

To develop strategies addressing the city-specific requirements, a stepwise simulation approach was used. Integrated Environmental Solutions–Virtual Environment (IES-VE) was used to create a prototype of a singly detached residence. The applicability of strategies is studied during the day and night times. Optimum orientation, the thickness of insulation, Window–Wall Ratio, the impact of cross-ventilation and shading depth are determined for two cities – Tiruchirappalli and Coimbatore under the warm-humid climate zone of India.

Results indicate that optimum insulation thickness and WWR vary between both cities during daytime and night time. In Tiruchirappalli, roof and wall insulation using polyurethane board (100 mm) and foam concrete (25 mm) offers a maximum reduction of 2.2°C indoors. Foam concrete (25 mm) insulation for roof and expanded polystyrene (25 mm) for walls reduce a maximum of 2.6°C during daytime in Coimbatore. Further, night ventilation with 20% WWR allows an average decrease of 0.5–0.6°C in triply exposed spaces facing the South. The use of a 2'0" depth shading device shows a maximum reduction of 0.1–0.3°C.

The contribution of this work lies in developing city-specific inputs presenting the advantage of easy replicability for other cities in the Indian context.

This paper aims to investigate the effect of titanium dioxide (TiO₂) nanoparticle coating on the visible reflectance and color appearance of dyed cotton fabrics.

A Taguchi experimental design model was used to minimize the number of samples and for accurate prediction of possible responses. The governing parameters affecting the color change of dyed fabrics through the coating process were selected as shade of cotton fabrics, depth of shade, concentration and size of TiO₂ nanoparticles and concentration of citric acid. The Taguchi model suggests the L18 orthogonal array. In the meantime, the lower response category was selected to determine the optimum conditions. According to obtained results, coating with TiO₂ nanoparticles results in color change (ΔEab*) of all dyed cotton fabrics.

The obtained results indicate that the TiO₂-coated fabrics had higher reflectance compared to raw fabrics. Furthermore, it was found that the TiO₂ pigmented coating increases the brightness of samples and simultaneously decreases their chroma. On the other hand, analysis of variance reveals that the concentration of TiO₂ nanoparticles together with shade of fabrics has the most significant impact on the color change of dyed fabrics through coating process. Dye concentration and size of TiO₂ particles also, to the same extent, had influence over the color change. However, the effect of the concentration of citric acid on the color change was insignificant.

This research investigates the effect of TiO₂ nanoparticles on the optical property of colored fabric by using a Taguchi experimental design model to minimize the number of samples.

Until recently only few organic yellow pigments with a sufficiently high standard of fastness —in particular fastness to light and weathering— were available for the manufacture of quality paints for outdoor use. In this article four new organic yellow pigments of high fastness are introduced. In a trial series these products were tested side by side with well‐established yellow pigments for their fastness to weathering in a stoving paint. For this purpose they were exposed to weathering in Florida for one year. The fastness to weathering was evaluated not only visually by the most widely used method, viz. comparison with the 5‐step Grey Scale, but also colorimetrically by determination of a ▵ AN value as a measure of any shade change which might have occurred. The values thus obtained are represented in various ways and compared with one another. Moreover, the fastness to weathering of the new and the old yellow pigments is compared with that of selected pigments of different shades which are also used for paints for outdoor use.

The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full evaluation of their use as disperse dye TF-ASC [bis 2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde Schiff base with 4,4'-methylenedianiline] for dyeing polyester fabric at various conditions.

The dispersed dye was synthesized via Schiff base condensation in the presence of ceric ammonium nitrate cerium ammonium nitrate 10 mmole% as an eco-friendly catalyst at room temperature. The chemical structure of the prepared dye was characterized via elemental analysis, Fourier-transform infrared spectroscopy, 1H- and 13 C-NMR spectroscopic analysis tools. This study thoroughly examined the dyeing of disperse dye TF-ASC on polyester at various conditions. The characteristics of dyed polyester fabric were measured by colour measurements, as well as light, washing, crock fastness and finally, colour strength. The discrete fourier transform (DFT) theoretical studies, including E_HOMO, E_LUMO and optimized geometrical structure, were assumed and discussed in detail.

The results showed that the synthesized organic dye TF-ASC was highly functional and appropriate for this kind of dyeing method. The dyeing fabrics obtained from disperse dye TF-ASC, properties possess high colour strength as well as good overall fastness properties. These dyes had a high affinity for polyester fabric, with just a tiny change in dye affinity when the pH was changed, even under alkaline circumstances. The dye levelness and shade depth of the colour results were good, and there were a variety of hues from light brownish yellow to deep brownish yellow. The results obtained from DFT computational studies such as E_HOMO, E_LUMO, optimized structure, diploe moment µ and electrophilicity index deduced that prepared organic dye TF-ASC is more applicable as a dispersed dye.

This research is significant because it provides a new dye for dyeing polyethylene terephthalate fibres with exceptional brightness and levelness; the method of preparation is a useful pathway due to its being known as a green chemistry method.

Porosity is one of the most important properties of the textile substrate. It can influence the comfort of a garment by affecting its breathability and thermal conductivity. During the process of dyeing, the dye liquor comes in contact with the substrate; the absorption of the dye liquor into the substrate will be dependent on its porosity. The concept of porosity between the yarns of fabric is a common phenomenon; however, the porosity between the fibres in the yarn can also influence the dyeing behaviour of the fabric.

In this research, ring and rotor yarns of 25/s and 30/s counts are considered as textile substrates. The porosity of yarns was determined theoretically and experimentally using the image analysis method.

It was found that theoretical porosity is independent of the yarn manufacturing method. In addition, 30/s yarn was more porous as compared with 25/s yarn having a higher pore area. Rotor yarns had higher porosity, dye fixation and K/S as compared with ring yarns. Dyeing behaviour was also dependent on the count of yarn. Specifically, 30/s yarns have higher dye fixation as compared with 25/s yarns. However, 25/s yarns were dyed with deeper shades showing higher K/S values. Also, 25/s yarns are coarser than 30/s yarns having higher diameters and cross-sectional area, thus resulting in deeper shades and higher K/S values.

This novel technique is based on the comparative study of the porosity of various types of yarns using the image analysis technique. This investigation shows that the porosity between the fibres in the yarn can also influence the dyeing behaviour of the yarn.

This paper aims to study microwave pad dyeing process for wool fabric. Influences of various dyeing process conditions including galactomannan dosage, urea dosage, sodium bisulphite dosage, pH value, microwave irradiation power, treating time and cold batching time before microwave fixation on K/S values were analysed. The colour yield, fixation and levelness were compared between microwave fixation and cold batching fixation.

Colour yield (K/S values) was calculated using a Datacolor SF650 colour measuring and matching instrument (10° standard observer, CIE D65 light source Measuring; Datacolor, USA) and was used to determine the depth of the shade of dyed wool fabrics. Levelness of dyeing was evaluated also using the Datacolor SF650 colour measuring and matching instrument by measuring average deviation (S), range (P) of the maximum and the minimum for lightness (L), chroma (C) and hue (h), and balanced colour difference (ΔE) at 20 specified uniform locations on the wool fabrics. The colour difference was calculated as per the equation ΔE=(ΔL2+Δa2+Δb2)1/2 as appearing in the Experimental section. Fixation was determined using a Datacolor SF650 colour measuring and matching instrument by measuring ratio the of K/S for wool fabrics that were rinsed, washed, neutralised and then dried, and wool fabrics that were dried after fixation without washing. The pH of the padding solution was evaluated using a PHSJ-4A PH meter (Datacolor, USA). SEM analysis was done on JEOL JSM-5600LV machine (JEOL Ltd, Japan).

This study is based on application of microwave technology in the processing of silk.

It was found in laboratory experiments that uniform dyeing and deeper colour can be achieved throughout the microwave pad dyeing process for wool by using galactomannan. The novel process could reduce the dyeing time and the energy consumption of the traditional cold pad-batch dyeing process for wool fabric.