Abstract: An assemblage of substantially round particles with a mean diameter between 0.1 and 4 mm, more preferable between 0.3 to 2 mm and most preferable between 0.8 to 1.2 mm, wherein the density of the assemblage determined by ISO 697 is between 250 kg/m3 and 400 kg/m3 is disclosed. The substantially round particles comprise at least one microporous material and optionally at least one binder, wherein the assemblage comprises a pore volume, wherein the pore volume comprises pores resulting from void space between different ones of the substantially round particles and pores within the substantially round particles.

Abstract: A loudspeaker device is presented which includes a zeolite material comprising zeolite particles having a silicon to aluminum mass ratio of at least 200. For an increased pore fraction of pores with a diameter in a range between 0.7 micrometer and 30 micrometer shows an increased shift of the resonance frequency down to lower frequencies has been observed.

Abstract: A loudspeaker device is presented which includes a zeolite material comprising zeolite particles having a silicon to aluminum mass ratio of at least 200. For an increased pore fraction of pores with a diameter in a range between 0.7 micrometer and 30 micrometer shows an increased shift of the resonance frequency down to lower frequencies has been observed.

Abstract: A loudspeaker device is presented which includes a zeolite material comprising zeolite particles having a silicon to aluminum mass ratio of at least 200. For an increased pore fraction of pores with a diameter in a range between 0.7 micrometer and 30 micrometer shows an increased shift of the resonance frequency down to lower frequencies has been observed.

Abstract: A substantially monodisperse assemblage of particles 10 having interconnected pores 20 and a core 30 with at least one shell 40, 60 disposed about the core 30 as well as a method for their synthesis is disclosed.