Disclosed in the present invention is a beam coherence eliminating element. The optical medium material of the element comprises microcrystalline glass, wherein microcrystalline particles therein have a size of 0.1-1000 nm and are distributed randomly. As the crystals in the microcrystalline glass can change the phase of light beams, the microcrystalline glass can change the phase of the light beams randomly, thereby eliminating the coherence of the beams. The crystal size of the microcrystalline glass is small, and thus does not affect the transmission efficiency of light beams. The element of the present invention has a simple structure and is convenient to use, and can be added in the process of beam transmission to easily eliminate beam coherence.

A composition includes 30 mol % to 60 mol % SiO.sub.2; 15 mol % to 40 mol % Al.sub.2O.sub.3; 5 mol % to 25 mol % Y.sub.2O.sub.3; 5 mol % to 15 mol % TiO.sub.2; and 0.1 mol % to 15 mol % RO, such that RO is a sum of MgO, CaO, SrO, and BaO.

A tubular member for an exhaust gas treatment device according to at least one embodiment of the present invention includes: a tubular main body made of a metal; and an insulating layer formed at least on an inner peripheral surface of the tubular main body. The insulating layer contains glass containing a crystalline substance, and the glass contains silicon, boron, and magnesium.

Provided is a Li.sub.2O-Al.sub.2O.sub.3-SiO.sub.2-based crystallized glass that has a high permeability to light in a ultraviolet to infrared range and is less likely to be broken. A Li.sub.2O-Al.sub.2O.sub.3-SiO.sub.2-based crystallized glass contains, in terms of % by mass, 40 to 90% Si.sub.O2, 5 to 30% Al.sub.2O.sub.3, 1 to 10% Li.sub.2O, 0 to 20% SnO.sub.2, 0 to 5% ZrO.sub.2, 0 to 10% MgO, 0 to 10% P.sub.2O.sub.5, and 0 to 4% TiO.sub.2 and a mass ratio of Li.sub.2O/(MgO+CaO+SrO+BaO+Na.sub.2O+K.sub.2O) is 3 or less.

Embodiments of the present invention pertain to antimicrobial glass compositions, glasses, and articles. The articles include a glass, which may include a glass phase and a cuprite phase. In other embodiments, the glasses include a plurality of Cu.sup.1+ ions, a degradable phase including B.sub.2O.sub.3, P.sub.2O.sub.5 and K.sub.2O, and a durable phase including SiO.sub.2. Other embodiments include glasses having a plurality of Cu.sup.1+ ions disposed on the surface of the glass and in the glass network and/or the glass matrix. The article may also include a polymer. The glasses and articles disclosed herein exhibit a 2 log reduction or greater in a concentration of at least one of Staphylococcus aureus, Enterobacter aerogenes, Pseudomonas aeruginosa bacteria, Methicillin Resistant Staphylococcus aureus, and E. coli, under the EPA Test Method for Efficacy of Copper Alloy as a Sanitizer testing condition and under Modified JIS Z 2801 for Bacteria testing conditions.

Methods for making articles comprising crystalline material. Exemplary articles made by a method described herein include electronics enclosure (e.g., a watch case, cellular phone case, or a tablet case).

A glass ceramic seal is formed from a precursor material that includes from 80 mol % to 100 mol % of a primary component containing, on an oxide basis, from 25 mol % to 55 mol % SiO.sub.2, from 20 mol % to 45 mol % CaO, from 5 mol % to 30 mol % MgO, and from 0 mol % to 15 mol % Al.sub.2O.sub.3.

A glass ceramic seal contains by weight, on an oxide basis 40-60% of SiO.sub.2, 25-28% of BaO, 10-20% of B.sub.2O.sub.3, 8-12% of Al.sub.2O.sub.3, 0-2% of ZrO.sub.2, 0-1% of Y.sub.2O.sub.3, 0-1% of CaO, and 0-1% of MgO.

A glass ceramic article including a lithium disilicate crystalline phase, a petalite crystalline phased, and a residual glass phase. The glass ceramic article has a warp (μm)<(3.65×10.sup.−9/μm×diagonal.sup.2) where diagonal is a diagonal measurement of the glass ceramic article in μm, a stress of less than 30 nm of retardation per mm of glass ceramic article thickness, a haze (%)<0.0994t+0.12 where t is the thickness of the glass ceramic article in mm, and an optical transmission (%)>0.91×10.sup.(2−0.03t) of electromagnetic radiation wavelengths from 450 nm to 800 nm, where t is the thickness of the glass ceramic article in mm.

A glass-ceramic includes glass and crystalline phases, where the crystalline phase includes non-stoichiometric suboxides of titanium, forming ‘bronze’-type solid state defect structures in which vacancies are occupied with dopant cations.