A device for decreasing hydrogen concentration of a fuel cell system is installed in an exhaust system for discharging exhaust gas which includes hydrogen and air and is discharged from fuel cells to the atmosphere through an exhaust line. The device includes a catalyst diluter having catalysts for diluting the hydrogen in an exhaust gas by generating a catalytic reaction and connected to the exhaust line. An air diluter is disposed outside the catalyst diluter and guides external air to a gas exit side of the catalyst diluter.

A device for decreasing hydrogen concentration of a fuel cell system is installed in an exhaust system of a fuel cell system so as to discharge exhaust gas including hydrogen and air from fuel cells to the atmosphere through an exhaust line. The device includes: a catalyst diluter that includes catalysts for diluting hydrogen in the exhaust gas by generating a catalytic reaction, the catalyst diluter being connected to the exhaust line; and an air diluter that is disposed outside the catalyst diluter and guides external air to a gas exit side of the catalyst diluter, in which the catalyst diluter may include a valve unit that opens and closes an external air channel of the air diluter in accordance with flow pressure of the exhaust gas.

In accordance with some embodiments herein, a filtering product is provided. The filtering product includes titanium dioxide (TiO.sub.2), cetrimonium bromide (CTAB) and ascorbic acid (C.sub.6H.sub.8O.sub.6). The filtering product may be used for filtering smoke of a water pipe. Alternatively and/or additionally, the filtering product may be used for filtering gas.

The present disclosure provides a catalyst for reducing CO and HC which is a core-shell particle including a core and a shell surrounding the core, the core includes metal oxide nanoparticles and noble metal nanoparticles fixed to the metal oxide nanoparticles, and the shell includes zirconia (ZrO.sub.2), and a layer from which the metal oxide is removed between the core and the shell is included.

A CON zeolite satisfying the following (1) to (2): (1) The framework is CON as per the code specified by the International Zeolite Association (IZA); and (2) It contains silicon and aluminum, and the molar ratio of aluminum to silicon is 0.04 or more.

Puncture elements and methods for using the same are disclosed. The puncture elements according to the disclosed concept include a cutting edge or a sharp and are composed of a mineral loaded polymer. The minerals of the mineral loaded polymer include an active agent, such as a desiccant. Optionally, the puncture elements are used to puncture a cover (e.g., foil seal) of a package.

The present invention relates to a metallic nanoparticle catalyst, and more particularly, to a porous catalyst in which metallic nanoparticles are embedded in a porous oxide support, and a method for preparing the porous catalyst. To this end, a porous catalyst composition having metallic nanoparticles of the present invention includes an oxide matrix structure having mesopores and micropores; and metal or metal oxide nanoparticles embedded in the oxide matrix structure having the mesopores and micropores. Thus, metallic nanoparticle catalysts having high activity even at low temperature are realized.

A method for producing a cluster-supporting catalyst, the cluster-supporting catalyst including porous carrier particles that has acid sites, and catalyst metal clusters supported within the pores of the porous carrier particles, includes the following steps: providing a dispersion liquid containing a dispersion medium and the porous carrier particles dispersed in the dispersion medium; and in the dispersion liquid, forming catalyst metal clusters having a positive charge, and supporting the catalyst metal clusters on the acid sites within the pores of the porous carrier particles through an electrostatic interaction.

Puncture elements and methods for using the same are disclosed. The puncture elements according to the disclosed concept include a cutting edge or a sharp and are composed of a mineral loaded polymer. The minerals of the mineral loaded polymer include an active agent, such as a desiccant. Optionally, the puncture elements are used to puncture a cover (e.g., foil seal) of a package.

The present disclosure provides msect-4 molecular sieves with OFF and ERI topologies, a preparation method therefor, and applications thereof. An eight-membered ring small pore molecular sieve used as a raw material is dispersed in an aqueous phase. Following that, caustic potash, an aluminum source, and an organic structure-directing agent (OSDA) are added. The pH value is then adjusted to be greater than 10, and a silicon source is introduced to attain the desired silicon-aluminum ratio, followed by stirring reaction, aging, crystallization, filtration, washing, ammonia exchange reaction, drying, and calcination. The msect-4 molecular sieves with OFF and ERI topologies, the preparation method therefor, and applications exhibit excellent hydrothermal stability, a plurality of adsorption sites exposed by a regular bone-like structure, and a large specific surface area. Consequently, this molecular sieves find applicability across various technical fields including selective catalytic reduction, passive adsorption, and catalytic cracking, and has broad application prospects.