Abstract: In the present invention, minute spherular silica gel particles suitable as polymer catalyst carriers can easily be obtained without using organic substances simply by controlling the moisture content in a slurry of silica hydrogel particles and water. The obtained spherular silica gel particles have physical properties, such as specific surface area, average pore diameter, and pore volume, that may be easily controlled. The spherular silica gel particles also have sufficient particle strength.

Abstract: This invention provides a method for manufacturing silica gels in a form of scales or needles having a pore volume and a specific surface area being relatively large and being controlled. Silicic acid sol is frozen, crystallized and deposited in gaps among crystal faces of crystals of solvent of the sol, thus obtaining the frozen silica hydrogels in the form of scales or needles. After unfreezing the frozen silica hydrogels, a hydrothermal polymerization is carried out. Subsequently, the silica hydrogels are dried, thus obtaining the silica gels in the form of scales or needles. Furthermore in the invention, by controlling the gelation time period of silica sol, the silica gels with their configuration controlled can result from even inexpensive silica sol. The invention has the advantage that a freeze-drying step is not required: just through freezing, unfreezing, washing and hydrothermal polymerization steps, the physical properties of the silica gels can be controlled.

Abstract: Specific inorganic silica gels are used as an adsorbent drying agent for controlling insect pests in a structure. When it is too humid in the structure, the silica gels adsorb moisture. On the other hand, when it is too dry in the structure, the silica gels supply moisture. The silica gels thus create the environment where household insect pests cannot survive. Moreover, by exposing invading insect pests to silica-gel particles, the pests' tissues are physiologically decayed, and the population density of the insect pests is decreased. Insect pests in the structure can be thus controlled using the silica gels.

Abstract: Specific inorganic silica gels are used as an adsorbent drying agent for controlling insect pests in a structure. When it is too humid in the structure, the silica gels adsorb moisture. On the other hand, when it is too dry in the structure, the silica gels supply moisture. The silica gels thus create the environment where household insect pests cannot survive. Moreover, by exposing invading insect pests to silica-gel particles, the pests' tissues are physiologically decayed, and the population density of the insect pests is decreased. Insect pests in the structure can by thus controlled using the silica gels.

Abstract: The actual flow rate of gas to the solid-sample container or to the gas reservoir can be precisely obtained according to variances in the pressure of the gas reservoir without directly adjusting the flow rate precisely. The volume of gas not adsorbed in the sample container can be obtained from the pressure in the sample container. The adsorption can easily be determined from the difference between the flow rate of gas and the volume of gas not adsorbed in the sample container. Even if the flow rate fluctuates, the adsorption can precisely be obtained. The desorption can easily be obtained in the same way. Gas is exhausted from the gas reservoir in advance. When desorbed gas in the sample container is continuously exhausted to the gas reservoir, the pressure in the gas reservoir is measured.

Abstract: There is provided by this invention a finely divided hydrated silica gel which has a specific surface area of 530 -720 m.sup.2 /g, preferably 550-650 m.sup.2 /g, a pore volume of 0.9-1.5 ml/g, preferably 1.0-1.4 ml/g, a mean pore diameter of 50-120 .ANG., preferably 60-100 .ANG., a water content of 7-25% by weight, preferably 8-13% by weight (wet weight basis), and moreover the pH of which as a 5% aqueous suspension is 6.0-8.0, thereby producing a silica gel suitable for stabilization treatment of beer, and for reduction of the colloidal components in beer.

Abstract: There is provided by this invention a finely divided hydrated silica gel which has a specific surface area of 530-720 m.sup.2 /g, preferably 550-650 m.sup.2 g, a pore volume of 0.9-1.5 ml/g, preferably 1.0-1.4 ml/g, a mean pore diameter of 50-120 .ANG., preferably 60-100 .ANG., a water content of 7-25% by weight, preferably 8-13% by weight (wet weight basis), and moreover the pH of which as a 5% aqueous suspension is 6.0-8.0, thereby producing a silica gel suitable for stabilization treatment of beer, and for reduction of the colloidal components in beer.

Abstract: A microorganism or enzyme is mixed with an alginate and a silica sol in the presence of water to obtain a liquid mixture having a pH of 3 to 10 and containing an alginate concentration of 0.5 to 3.5% (w/v) and a silica concentration originating from the silica sol of 0.5 to 35% (w/v). The mixture is contacted with a gelling agent in the form of an aqueous solution to obtain a gel containing the microorganism or enzyme.