When the wood was delignified by sodium chlorite, we found obviously that the yield was more than theoretical yield which was calculated from analytical lignin content. This deviation showed the maximum value (over 6 per cent based on the original wood) at the sample having 10-13 per cent lignin contents. In the case of lower lignin contents the deviation value reduced again, and when the lignin contents decreased extremely and the polysaccharides were dissolved considerably, the practical yield was less than the theoretical yield.
We attempted a few study for this curious fact. As a result, we found that a part of lignin which was oxidized by sodium chlorite lost condensation ability anddissolved in acids at analytical procedure, so the analytical lignin content was given low value. We confirmed that this deviation decreased if the lignin contents were calculated from the methoxyl contents of the lignins in samples.

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At first, a study has made of the effect of moisture content on the electrical resistance of the sample, but it has been found that the electrical resistance was effected not only by the variations in the fiber furnish, but the electrical resistance of the stock, from which the sample was made of.
Next, a study has made on the methods of measuring the dielectric constant of the sample. We used two condencers. One of them was a paper-condencer. which is made of the sample inserted between two plates. The other was a air-condencer, which is made of two plates, and the distance of them was a function of the sample thickness.
When we compare with these two condencers by the cross coil meter, we get the dielectric constant of the sample, which has no relation with the thickness variation of the sample.
Measurements were made to ditermine the effect on the dielectric constant-moisturecharacteristic of variations in fiber furnish, thickness, density, etc. It was found that. the effect of these variations needs calibration curve for each sheet.
The accuracy of this meter is 0.1% when we use a caribration curve which based on the bulk of the sheet.

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[in Japanese]

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