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In recent years, the textile industry has been required to develop new methods and technologies through introduction of some new materials in various processes rather than employing the same conventional chemicals. The aim of this research was to investigate the changes induced on the cotton fibre by the nanoclay treatment using a pre‐treatment method.

The fibres were dyed with basic and direct dyes after the nanoclay pre‐treatment. Technical measurements were studied including Fourier‐transform infrared spectroscopy (FTIR), UV‐visible spectrophotometer, differential scanning calorimetry (DSC), thermal degradation analysis (TGA), scanning electron microscopy (SEM), moisture regain measurement (MRM), tensile strength test (TST), reflectance spectroscopy (RS) and fastnesses evaluation.

The intensity of the major peaks in FTIR spectra of the nanoclay treated sample is in favour of the chemical changes of the cellulose functional groups. Basic dyes showed a higher dyeability on the clay pre‐treated samples compared to raw materials. The results of the colour measurements showed that the more concentration of the clay mineral was used, the darker the colour of the dyed sample was. Some interesting results were obtained in the research.

The nanoclay and a dispersing agent used in the present context were used as received. Besides, the type of the dispersing agent is important for preparation of a colloidal dispersion of nanoclay.

The method developed in this research provides a simple and practical solution for improving the dyeability of cotton with direct and basic dyes.

The method for enhancing the dyeability of cotton is novel and can be used in cotton processing with new properties.

An indoor office space should not only provide adequate illuminance on horizontal planes but also cater to the physiological and psychological requirements of the occupants. This paper aims to describe a lighting simulation-based work conducted in Kolkata, India which modeled an indoor office to investigate the effects of variation in room surface reflectance combinations on user perception, mean room surface exitance (MRSE), average horizontal illuminance and overall uniformity of horizontal illuminance.

A fluorescent illumination system–based office space was modeled and retrofitted with tubular LED lamps in DIALux. Simulations were conducted for 16 different room surface reflectance combinations and a five-point Likert scale-type survey questionnaire was formulated to conduct a survey with 32 test subjects to assess the subjective preferability of each resultant light scene.

Simulation results demonstrate that the relationship between average horizontal illuminance and MRSE as well as between average horizontal illuminance and overall uniformity of horizontal illuminance, was statistically significant (p < 0.001). In the conducted survey, the resultant light scene arising out of the reflectance combination of wall:ceiling:floor = 60%:90%:20% was the most well-received one with 187 convinced agreements (“agree” and “strongly agree” responses).

This work found strong linear correlation between average horizontal illuminance and MRSE and between average horizontal illuminance and overall uniformity. A five-point Likert scale-type survey questionnaire with seven questions was formulated and validated with 32 test subjects (Cronbach’s alpha > 0.9295), which showed that the wall:ceiling:floor reflectance combination of 60%:90%:20% was the most favored choice.

Over the last few years it has been established that there is a need to re‐evaluate the basis of assessment of the sufficiency of daylight, in rights to light cases, where the loss of daylight after obstruction might lead to injunction and/or damages. The purpose of this paper is to further examine whether the methodology used by surveyors, whereby the effect of glazing, window frames and internal reflectance are ignored, is valid and whether theoretical values can be translated into real values obtained through practical experimentation.

Modern methods of assessment of daylighting, for design purposes, calculate a whole room average as a percentage of available daylight from a Commission Internationale de l’Eclairage (CIE) sky whereas Waldram's methodology, in rights to light cases, results in a contour line marking the series of points in a room where the task lighting, from a uniform sky, would be insufficient for normal use. These two methods appear incompatible and the conundrum is that whilst the courts are seeking to determine adequacy of daylighting to a room, the practitioners need to be able to measure the reduction in a way that has real meaning and can be valued.

By comparing theoretical results using the Waldram methodology with those obtained using the Building Research Establishment (BRE) methodology and with physical measurements on site and in an artificial sky dome, it can be demonstrated that results using the Waldram Diagram, or the proposed CIEL Diagram, can be translated into real values of daylighting for a room and that these values are more realistic than those obtained through the BRE methodology.

This research (which is ongoing) will be useful to practitioners and the courts in determining rights to light cases and is a significant contribution to the debate initiated in this journal by Michael Pitts some 12 years ago.

In this article, a simple system will be presented to measure reflectance of metallic surfaces quickly and precisely based on goniospectrophotometric geometry. The paper aims to discuss these issues.

This system works by capturing reflected light from different colored patches by digital camera and with the knowledge of spectral power distribution of light source and defined observer, reflection of each sample can be reproduced. By fixing the light source, the position of the detector would be eliminated to four angles of observation.

This method can achieve acceptable reconstruction accuracy for metallic samples. This approach confirmed repeatability and practicality of the simple imaging acquisition to replace spectral reflectance measurement devices in different viewing angles.

The reflectance of metallic samples has been measured at several angles such as 20°, 45°, 75° and 110° from specular reflection. A simple system was used to measure multi-angle reflectance of metallic surfaces by digital camera. By suggested system can be measured the reflectance without contact and limitation in the shape of surfaces. This method achieved acceptable reconstruction accuracy for metallic samples. This simple imaging acquisition is comparable with goniospectrophotometer for measuring multi-angle reflectance of metallic samples.

Good illumination creates an aesthetic environment that may positively influence patients’ well-being and provide comfort to the hospital staff. This study aims to focus on exploring the energy efficiency of lighting and subjective perception of the lit environment in a hospital ward to assess quality indicators of ambient lighting conditions.

The existing conventional tubular fluorescent lamp–based lighting system in the surveyed patients’ ward was retrofitted with light-emitting diode (LED) luminaires to explore illumination and energy parameters. Thereafter, a software lighting model was created, simulated and analyzed. A Web-based survey with five bipolar adjective pairs in a semantic differential scale was conducted with 48 participants to record and analyze their subjective responses pertaining to the variations in lamp types and surface reflectance combinations.

The findings imply that the LED tubular lamp–based illumination was deemed more adequate compared to other lamp types and the effects of variations in room surface reflectance combinations on the participants’ responses were statistically significant at α = 0.05 level. The simulated horizontal work plane average illuminance level varied from 131 to 171 lx, mean room surface exitance (MRSE) levels remained between 30 and 90 lm/m² and overall uniformity of illuminance remained between 0.5 and 0.7.

In a hospital ward illuminated by LED tubular lamps, variations in room surface reflectance combinations for a constant luminous flux package output from the lamps may affect the subjective perception of users and the correlation between horizontal work plane average illuminance and MRSE is found to be highly linear (coefficient of determination > 0.97).

The rapid growth of the powder coatings industry over the past ten years has brought with it dramatic changes in the technology of the manufacturing process and in the products themselves. Powder coatings have become recognised as a high performance and cost‐effective alternative to conventional wet paint systems. The increasing numbers of discerning end users who have adopted powder as a finishing process have demanded demonstrable improvements in product quality and performance over their existing finishing systems. This has lent additional impetus to the drive for better products and has accelerated the pace of technological change within the industry. Pressure on powder manufacturers has resulted in increasingly tighter requirements for consistency of product quality and none more so than in control of the colour of the powder coating, especially for demanding applications such as architectural and domestic appliance coatings.

In many markets customers judge the quality of products by their surface appearance. The term gloss describes the perception of the shiny appearance of a surface when light is reflected from that surface. Imperfections in a surface cause some of the light to be reflected/scattered at angles away from the specular and this impacts on the visual assessment of appearance. A method has existed for measuring surface reflectance for the last 50 years, but its usefulness has been limited by an inability to equal the human eye in discerning subtleties such as haze or distinctness of reflected images. A portable instrument has now been developed to take measurements about the specular, spaced at less than three minutes of arc. This paper explains how this high resolution supports the introduction of additional indices to define haze, distinctness of image and peak specular reflectance while retaining the definition of “gloss” as described in the standard method ISO2813.

The aim is to holistically assess the environmental performance of windows and analyse how their design and characteristics contribute to the overall performance of the building/space. This study focuses on the performance of windows in patient rooms hosting less mobile people.

This study investigates the life cycle environmental impacts of different glazing types, window frames and fire safety doors at the product level. This article also presents a building-integrated environmental analysis of patient rooms that considers the multiple functionalities of windows by incorporating dynamic energy analysis, comfort and daylighting performance with a life cycle assessment (LCA) study.

The results indicate that the amount of flat glass is the main contributor to the environmental impacts of the glazing units. As for the patient rooms, global warming shows the most significant contribution to the environmental costs, followed by human toxicity, particulate matter formation and eutrophication. The key drivers for these impacts are production processes and operational energy use. This study highlights the significance of evaluating a wide range of criteria for assessing the performance of windows.

An integrated assessment approach is used to investigate the influence of windows on environmental performance by considering the link between window/design parameters and their effects on energy use/costs, daylighting, comfort and environmental impacts. The embodied impacts of different building elements and the influence of various design parameters on environmental performance are assessed and compared. The environmental costs are expressed as an external environmental cost (euro).

Visible and near infrared spectroscopy have been applied widely in fruits quality assessment especially on the measurement of soluble solids content (SSC) measured in ^oBrix and acidity measured in pH. Spectroscopy technique has been applied on three botanically different categories of fruits, that is: imported Californian table grape, Mandarin lime and star fruit. The purpose is to examine the ability of spectroscopy technique to quantify internal quality parameters with very narrow variability due to the characteristics of the raw material analyzed. This work also presents comparative study on peak wavelengths that can best be used to calibrate SSC and pH of different types of fruits.

The effective wavelengths chosen for calibration development are compared with those selected by other researchers in similar experiments. NIR wavelengths 910 nm (C−H band) and 950 nm (O−H band) are the most important wavelengths for the prediction of SSC for all examined fruits while wavelengths 922‐923 nm and 990‐995 nm for pH. Visible wavelength 605, 675 and 654 nm can efficiently improve the SSC and pH prediction for grape, lime and star fruit, respectively.

The best prediction for SSC has been achieved with R²=0.953 and RMSE=0.182 for grape, R²=0.918 and RMSE=0.109 for lime and R²=0.957 and RMSE=0.354 for star fruit. The best prediction for pH has been achieved with R²=0.763 and RMSE=0.110 for grape, R²=0.841 and RMSE=0.073 for lime and R²=0.862 and RMSE=0.261 for star fruit.

Currently, the spectroscopy research conducted for the measurement of fruits qualities is conducted through wide range spectrometer. However, the peak responses are only located at specific wavelengths. Hence, the selection of wavelengths related to SSC and pH will allow the design of low cost instruments for the prediction of these internal quality parameters.

For a better picture still of the fastness to weathering of the various pigments in the chosen paint system, it is worthwhile studying more closely the reflectance curves which were measured before and after weathering for the determination of the AN values. In Figure 10 the reflectance curves of the non‐weathered and the weathered areas of the test panels are shown in pairs, again in order of decreasing fastness, i.e. beginning with the pigment with the smallest AN value. However, only the reflectance curves of the 1:50 reductions are shown.