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Windows 7 Dark Glass 20

Stained Glass are a group of walls made from combining gems with Glass Walls. They work like the normal Glass Wall besides changing the color of the sunlight to match that of the stained glass. Multicolored Stained Glass causes sunlight to shift through the color spectrum in a similar manner to Rainbow Brick, although dimmer.

Windows 7 Dark Glass 20

I was looking for a piece of software that would act like a dark mode you find on many apps and websites nowadays. After checking out the settings in the trial version, especially the dark mode which I was specifically after, I was so impressed I decided to pay for the lifetime license

There are many practical reasons for window tinting auto glass, but the aesthetic appeal is often the deciding factor. Dark windows add style and flair and can make even older, cheaper cars look like luxury vehicles. If you are interested in tinting your auto glass Spartanburg SC has many great window tinting shops.

Cons While tinted windows are good for temperature control, protect from the sun, and look stylish, there are a few reasons why you may want to think twice about getting your windows tinted.

Window tinting is designed so that you can see through the windows from inside the vehicle, but it still somewhat limits visibility. This is especially true at night or when passing through a tunnel. If you have poor vision at night, tinted windows are probably not for you.

This work presents the results of the evaluation of two Art Nouveau glass windows from the Casa-Museu Dr. Anastácio Gonçalves (Lisbon, Portugal) with IR-thermography during the summer solstice. According to the measurements, the surface temperature of glass depended on the outdoor environmental temperature and, mainly, on the direct solar radiation. Colored glasses presented a higher surface temperature due to the absorption of their chromophores at near-IR wavelengths. Enamels and grisailles showed higher surface temperatures than their support glasses due to both their chemical composition and color. The protective glazing, with small slits in one of the window panels, induced a hot-air pocket in its upper part due to the insufficient ventilation.

Stained-glass windows are large complex works formed by colored glasses in which the lead cames and the grisaille painting define the contours and shadows. They can also be made of uncolored pieces of glass painted with enamels and grisailles, these are normally denoted as glass panels [1,2,3]. The aim of both glass windows is to illuminate the inner part of the building, such as normal windows; but also to serve as decoration when the light illuminates them. In religious buildings, this latter function is frequently related to an instructive purpose; but in civil buildings, they are decorative elements usually with geometric patterns, symbolic elements, or landscapes. The stained-glass windows protect also the building from the external environmental conditions.

Rain and pollution are the environmental factors that contribute most for the glass alteration [4,5,6,7,8,9,10,11,12]; nevertheless, temperature has also a significant role [13,14,15,16,17]. From the physical point of view, solar radiation can induce the movement of the stained-glass windows due to the dilatation of the different materials [14]. Nevertheless, the main damage due to temperature fluctuations can be observed on surface paints (enamels, grisailles), which can present cracking, flaking, and, eventually, the detachment of the paints from the glass support due to their different dilatation coefficient. This effect has been observed principally on historical bluish enamels [18,19,20].

To map the natural heating of the different materials on stained-glass windows, it is necessary to use infrared (IR) thermography, a portable technique capable of measuring in situ the temperature on different areas and over time. This technique has been applied to evaluate the thermal efficiency of different windows systems [21, 22], as well as, to evaluate glasses with different industrial purposes [23,24,25,26], to research fire endurance of tempered glass [27], to study the mechanical defects and the elastic deformations on glass sheets [28,29,30,31,32], and to analyze the efficiency of solar cells [33, 34]. The application of IR-thermography on historical glasses is scarce [20, 32, 33]; nevertheless, these studies proved to be a useful tool to evaluate the conservation of historical stained-glass windows [35, 36].

The main objective of this research was to assess the natural heating of two Art Nouveau glass windows from the Casa-Museu Dr. Anastácio Gonçalves (Lisbon, Portugal) with IR-thermography for the period of one day during the maximum amplitude of sun radiation (summer solstice) to identify the influence of the environmental temperature, the solar radiation and the protective glazing on the glasses, surface paints and other materials related to the glass windows.

The comparison between the temperature inside and outside the building showed that, in general, the apparent surface temperature measured on the indoor glass surface was higher than the external environmental temperature due to the greenhouse effect produced inside the building. Nevertheless, both temperatures were related because they presented a similar heating and cooling behavior (Fig. 2a, b).

During the morning, when the sun did not impact directly on the panels, it was observed a slow increase of the temperature due to the conduction of environmental heat through the glasses. This heat flow depends on the temperature gradient, as well as on the own characteristics of the glass [37].

The colorless glass in the Dining room panel rose up to 32 C (Fig. 2a), just due to the influence of the external environmental temperature. In the case of the Atelier panel, the temperature detected on the colorless glasses in the middle of the panel rose up to 30 C (Fig. 2b).

The direct solar radiation was the most important factor in the temperature of the glass windows. Nevertheless, it experienced slight variations due to the shadow produced by surrounding trees and buildings (Fig. 2a, b). The Dining room stained-glass window had more than 5 h of direct solar radiation, and the Atelier just 4 h. This different duration of sun exposure is due to the orientation of the windows in the building (Fig. 1).

These thermal variations were higher than those observed in two monitored French churches (the Sainte Urbain Basilica in Troyes and the Saint Chapelle in Paris) [38]; nevertheless, the rate of the temperature increase/decrease was slower due to the protective glazing and, probably, to the shadowing of the windows.

a Dining room stained-glass window, and the apparent surface temperature maps at: b before the sunrise, c before the solar radiation, d during the maximum impact of the solar radiation

On the Dining room stained-glass window, it was possible to observe that some glasses increased more their surface temperature during the day (Fig. 4b, c). This phenomenon could be produced by the thickness of the glass and/or their different color.

Regarding the thickness, the conduction of the heat from outside is faster in thin glasses due to the less distance between both surfaces. In the Dining room panel, some glasses (the hydrangeas on the left side of the panel and the irises on the right one) were acid etched to create different hues and volumes; but it was not detected local heating in the thinner areas. Furthermore, glaziers normally use glasses with similar thickness on stained-glass windows to better secure them with the lead came [43]. Thus, the different thermal behaviors were not correlated to the glass thickness.

The inner surface of both windows was painted with grisailles and enamels. A grisaille is a dark paint applied to draw the contours and details of the figures, and to produce the effect of shades and volumes. The grisailles are made by powdering a highly fusible glass, usually lead glass, with pigments such as iron or copper oxides, but it can also contain tin, and/or manganese oxides. During firing, the grains of fusible glass melt and fix the pigment grains onto the glass surface [52,53,54,55]. On the other hand, an enamel is a brightly colored paint formed by a highly fusible glass, a lead glass with/without borax, with a small amount of pigment. The powdery enamel is applied onto the glass pane with a brush and then fired. The result is a thin homogeneous layer of glass of bright color on the glass surface [52, 56].

Soda-lime silicate glasses have a higher specific heat than high-lead glasses [42, 57]. This means that, in the same conditions, the support glass, a soda-lime silicate glass, need more energy to raise one degree Celsius than the surface paints, prepared with high-lead glasses. In other words, for the same energy, the surface paints should increase more their temperature than the support glass, as it was observed. In addition, the thermal conductivity of borosilicate flint glasses and the heavy flint glasses (surface paints) is slightly lower than soda-lime silicates (support glass) (Table 1) [58], which favors accumulation of heat in the enamels and grisailles instead of their transmission to the support glass (Fig. 7a, b).

The different surface temperature observed on the paint and the support glass could promote the thermal incompatibility in the Atelier panel, mainly on bluish and purplish enamels, favoring the formation of fissures and the mass loss [59].

Two Art Nouveau glass windows from the Casa-Museu Dr. Anastácio Gonçalves were characterized with IR-thermography within the period of one day during the summer solstice. It was evaluated the influence of the environmental temperature, the solar radiation and the protective glazing on the glasses, surface paints and other materials related to the glass windows.

The outdoor temperature favored the thermal flow through the glass, increasing its indoor surface temperature. Nevertheless, the most important factor on the temperature of the glass windows was the direct solar radiation, which could increase the surface temperature up to 40 C in the Dining room glass window and 35 C in the Atelier panel. The different behavior depended on the orientation of the window, the dimension of the room and, probably, the outdoor temperature. Regarding the colored glasses, the green areas showed the highest surface temperature because of the chromophores (iron and copper ions) in the near IR-region; in contrast to colorless glasses, which presented the lowest temperatures due to the absence of chromophores. Concerning the enamels and grisailles, they increased their surface temperature in comparison with the glass support due to the lower specific heat and thermal conductivity of the high-lead glasses and borosilicate glasses.

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