The semimicro determination of the methoxyl content of wood was studied, and a method for this determination was developed. The wood samples used in this study were 20-mesh powders of red pine and cedar, the sulfur contents of which were very small or negligible.
The procedure developed is similar in principle to Tappi methods, and the apparatus employed is a modification of the one designed by Neumann for micro methoxyl determination. In the present method, about 10-30 mg. of wood powder is heated with 2 ml. of hydriodic acid (b.p. 126-127°C) for 40 min. and the reaction mixture is then allowed to cool to room temperature in 20 min. During the heating and cooling periods, carbon dioxide or nitrogen gas is passed through the apparatus at a rate of 20-30 ml./min. The distillate is collected in an absorption trap (contg. 2 ml. of Br-AcONa-AcOH soln.) and titrated with 0.02N-thiosulfate solution. In the above treatment, solvents (such as conventionally used) may be added to the sample. Also, scrubbers may be used, but are dispensable if the sample contains scarcely any sulfur. In all cases, however, blank tests must be conducted by employing the same amounts of reagents as used in the sample analysis. This is because blank values are so great that they cannot be ignored.
In so far as blank corrections are made, results of determination are reproducible. In experiments with wood powders, such results were obtained with or without the use of solvents and scrubbing reagents. Also, in experiments with vanillin and acetyl vanillin, the methoxyl contents thus determined agreed with the theoretical values. Choice between carbon dioxide and nitrogen gases is immaterial.

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Use of ammonium sulfamate as an aid in chlorination and hypochlorite stages of pulp bleaching has been studied through laboratory work and mill operation. The following conclusions are obtained.
1) The addition of 5% ammonium sulfamate based on available chlorine in the hypochlorite stage of sulfite pulp bleaching by the GEH sequence makes effects of temperature and pH milder, and produces pulp with qualities fairly comparable to that by the CEHD sequence using chlorine dioxide only by temperature increase of 4 to 7°C, with reasonable bleaching cost, and simplicity of use. Otherwise the use of ammonium sulfamate in the chlorination stage is not so effective as in the hypochlorite stage.
2) The use of ammonium sulfamate in chlorination and hypochlorite stages of kraft pulp bleaching by conventional multiple sequence including chlorine dioxide stage has less effective on bleached pulp, but when semibleaching is carried out by less than 3 stages, or hypochlorite is increased in order to get higher brightness, its use in the hypochlorite stage is markedly effective.

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This paper presents brief discussion on the relationship between Hunter Whiteness, Brightness and yellowness of pulp sheet.
Hunter Whiteness (W) is defined as follow,
W= [1- {(30√α²+β²) ²+ (1-G/2) ²} ^1/2] ×100
α;2.5 (A-G) /10G
β; (G-B) /10G
Brightness (B) is a numerical value of the reflection of pulp sheet to light in the blue portion of the spectrum, specifically to a wave length of 457 millimicrons.
Yellowness (Y) is given as fellow,
Y= (A-B) /G×100
Whiteness, Brightness and Yellowness of the about 150 samples; commercial, aged, and deteriorated pulps, were calculated from the measurements of Hunter Reflectmeter, respectively.
It was confirmed that (W) and (B) were closely connected with each other. However, in the limited Brightness range the reliability of this relation was doubtful.
It was found that Yellowness had a high intensive connection with Whiteness and was useful as a aviable measure to determine the pulp sheet colouring.

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