Gaseous inclusion

Melting defects must be held to a minimum, SoHd inclusions (stones) in the form of refractory particles, unmelted batch, or devitrification, affect the strength as weU as optical integrity. Gaseous inclusions (seeds and bHsters) caused by improper fining or electrochemical rebod, have the same effect as striae (cords) from improper homogenization. 

The nature of solid, liquid or gaseous inclusions that may be found within transparent inorganic glass or crystalline materials can be determined by Raman microprobe techniques without breaking up the sample (39). Other analytical techniques, such as mass spectroscopy or electron microscopy, that may be used to obtain such information require destruction of the original sample. This capability of the microprobe is useful if one wants to analyze inclusions in a material before and after a sample treatment. The only limitation is that the position of the inclusion in the material must be located within the working distance of the objective lens in the microscope (39). 

We point out that the elasticity of the lamella, which is the basic topological element of the foam structure separating the disperse gaseous inclusions, must be substantially larger than the elasticity of the adsorption layer. 

Foam sheets are a foamed sheet pol3Tner material containing Cl in the pol3Tner base and as gaseous inclusions. The Zerust Ferrous Foam Sheet material is able to lower the risk of damage of fragile metal articles in transit and protects them against corrosion. 

The terms fining and refining refer to the removal of gaseous inclusions, or bubbles, from the melt. Although the presence of bubbles in a glass sample is not necessarily detrimental for many scientific studies, bubbles are definitely undesirable in most commercial glasses. Bubbles in commercial products are almost always considered flaws and result in rejection of the product. These gas-filled inclusions may occur as very small spheres (< 0.4 mm diameter), which are frequently called seed... 

One example of the application of this technique is the investigation of different phases of fluid inclusions in a quartz crystal found in the Swiss Alps. Their Raman spectra permitted determination of CO2 as a gaseous inclusion and water as a liquid inclusion, and they showed that the mineral thought to be CaS04 was in factCaCOs [367]. 

Nondestructive analysis of various materials, such as rocks, composite materials, phases and inclusions in solids, can be performed with a laser molecular microprobe [9.28], which is based on a combination of an optical microscope with a Raman spectrometer. The laser beam is focused into the sample and the Raman spectrum, emitted from the small focal spot, is monitored through the microscope. The principal modes of operation were illustrated by studying the different phases of "fluid inclusions" contained in a quartz crystal from the Swiss Alps. The Raman spectra obtained permit determination of CO2 as a gaseous inclusion, water as liquid inclusion, and the fact that the mineral, thought to be CaSO, is in fact CaCO. ... 

Gaseous inclusion a section affected by porosity cannot be longer than 1.6mm and their total must not exceed the length of 3.2mm each 6.5 cm2 of weld surface. 

The logical implication of Eq. (46) for dynamic contact angles (i.e., for a moving contact line) is that solders will wet a partially oxidized surface at a slower rate than the pure metal. The rate of advance of the contact line over the patch depends on pinning dynamics. The shape of the contact line is distorted at each point the liquid encounters an oxide patch. Contact line motion on heterogeneous surfaces typically exhibits an erratic behavior often referred to as stick-slip motion. It is possible that a gaseous inclusion will be formed when the solder negotiates a patch if the surfaces of the deformed liquid on either side of the patch coalesce before the entire patch is wetted. 

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