摘要:
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. Since the adsorption and desorption are thus precisely obtained, the adsorption or desorption isotherm can be drawn by plotting the pressure at each point of time and the corresponding adsorption or desorption of the solid sample. Consequently, the surface area, pore diameter distribution, pore volume and the like of the solid sample can precisely be calculated.
摘要:
A process for producing scaly or acicular silica gel having relatively large and controlled pore volume and specific surface, which comprises freezing silicic acid sol to deposit the crystallized sol in a gap between the faces of solvent crystals to thereby form frozen scaly or acicular silica gel, thawing the frozen silica hydrogel, conducting hydrothermal polymerization thereof, and drying the resultant hydrogel. This process is advantageous in that the shape control is possible with inexpensive silica sol by controlling the gelation time of the sol, that freeze drying is unnecessary, and that the physical properties of the silica gel can be controlled by conducting thawing, water washing and hydrothermal polymerization after freezing.
摘要:
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.
摘要:
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.
摘要:
There is provided by this invention a finely divided hydrated silica gel which has a specific surface area of 530 -720 m 2 /g, preferably 550 -650 m 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 A, preferably 60 -100 A, 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.
摘要:
A process for producing scaly or acicular silica gel having relatively large and controlled pore volume and specific surface, which comprises freezing silicic acid sol to deposit the crystallized sol in a gap between the faces of solvent crystals to thereby form frozen scaly or acicular silica gel, thawing the frozen silica hydrogel, conducting hydrothermal polymerization thereof, and drying the resultant hydrogel. This process is advantageous in that the shape control is possible with inexpensive silica sol by controlling the gelation time of the sol, that freeze drying is unnecessary, and that the physical properties of the silica gel can be controlled by conducting thawing, water washing and hydrothermal polymerization after freezing.