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Volume 41, Issue 4
Displaying 1-9 of 9 articles from this issue
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Shiro Saka1987 Volume 41 Issue 4 Pages 293-302
Published: April 01, 1987
Released on J-STAGE: October 27, 2010
JOURNAL FREE ACCESSA conventional electron microscope coupled with an energy dispersive X-ray analyser (EDXA) is a powerful tool with ability to study fine details of morphology. Therefore, it has been usedto study the topochemistry of wood and pulp fibers.
In this review, the discussion was focused on the quantitative analysis of EDXA methodand application of this method to the wood research, placing a special emphasis on the distributionof lignin by bromination coupled with EDXA technique.View full abstractDownload PDF (3373K) -
Hideki Izumi, Yoshio Yoshida1987 Volume 41 Issue 4 Pages 303-308
Published: April 01, 1987
Released on J-STAGE: October 27, 2010
JOURNAL FREE ACCESSA data processing system for paper testing utilising local area network (LAN) has beendeveloped as a part of laboratory automation program. The system consists of paper testinginstruments, personal computers, and a LAN network. Testing results are made into a reportby communicating data between instruments and computers, and between computers.View full abstractDownload PDF (941K) -
Toshio Fukuzumi1987 Volume 41 Issue 4 Pages 309-315
Published: April 01, 1987
Released on J-STAGE: October 27, 2010
JOURNAL FREE ACCESSDownload PDF (1960K) -
Andrew Garner, Tatsuo Itakura, Atsushi Mori, Koichi Nakano1987 Volume 41 Issue 4 Pages 316-322
Published: April 01, 1987
Released on J-STAGE: November 29, 2010
JOURNAL FREE ACCESSAn electrochemical protection technique is described which protects stainless steel bleachedpulp washers from corrosive attack. The oxidizing effects of residual chlorine or chlorinedioxide in pulp slurries are countered by cathodic polarization of the stainless steel to a passivepotential. The electrochemical principles of protection, and the crevice corrosion monitoringtechnique, are outlined, together with results from some of the over 80 protection systemswhich are now in orteration around the world.View full abstractDownload PDF (1785K) -
Kunio Miyagawa1987 Volume 41 Issue 4 Pages 323-333
Published: April 01, 1987
Released on J-STAGE: October 27, 2010
JOURNAL FREE ACCESSMovement to higher brightness and clealiness of deinked pulp is going to be accelerated. The system and equipment meeting this movement are required. Sulzer Escher Wyss, WestGermany has been offering unique technology not only in paper-making, but also in wastepaper-treating.
Hitachi Zosen group is making efforts to introduse Escher Wyss good technology whichcopes with the current movement.
In this paper, Escher Wyss technology is introduced from the viewpoint of how to obtainhigher brightness and clealiness of deinked pulp.View full abstractDownload PDF (4397K) -
(2) Derivation of Approximate Curl Formulas and their ApplicabilityTetsu Uesaka, Tokuro Ishizawa, Isao Kodaka, Shunsuke Okushima, Ryousuk ...1987 Volume 41 Issue 4 Pages 335-341
Published: April 01, 1987
Released on J-STAGE: October 27, 2010
JOURNAL FREE ACCESSApproximate formulas for predicting reversible curl behavior have been derived from the lamination theory of curl, which was developed by Carlsson.
Paper sheet is considered here as a laminate which consists of “wire” side and “felt” side sheet having equal thickness and different properties. If difference in elastic constants of both sides is small as compared with their average values over the thickness, curvature equation in the lamination theory is systematically approximated, as described in Appendix I. For relatively small orientation angles, the formulas are expressed as eqs.(1) through (3), which include expansion coefficients, orientation angles, moisture (or temperature) changes and thickness as main parameters. The formulas revealed that bending curl is mainly determined by the difference in expansion coefficients of both sides, while twisting curl is strongly dependent on the orientation angle and the degree of anisotropy.
The validity of the formulas has been established through numerical comparison with the exact solutions. It was found that the bending curvature can be described even by the first term of the formula for the case of small orientation angles or weak anisotropy. In order to determine applicability of the two-layer model for the case of real sheets, fine paper samples were ground by using a specially designed surface grinder to obtain wire and felt side sheets, and expansion coefficients and orientation angles were determined for each side to predict the curvature components by using the curl formulas. A general agreement has been found between measured and predicted curl changes.View full abstractDownload PDF (1045K) -
Atsumi Yasunaga, Hisakazu Takeuchi, Sadatoshi Meguro, Hiroyuki Imamura1987 Volume 41 Issue 4 Pages 342-348
Published: April 01, 1987
Released on J-STAGE: October 27, 2010
JOURNAL FREE ACCESSIn order to clalify the effects of agitation rate on the oxygen delignification of white birch Asplund pulp, the relationship between the change of oxygen content in a cooking liquor during the course of cooking under a constant oxygen pressure and Kappa number of the pulp was investigated.
The rapid consumption of oxygen dissolved in cooking liquor resulted from the significant increase in the delignification rate during the early stage by the addition of Co-salen [Cobalt (II) Bis-(salicylidene)-ethylenediamine] as a oxidizing catalyst.(Table I and Fig. 3). Thus, the dissolved oxygen content decreased, and the pulp was under oxygen shortage temporarily in the case of the agitation rate below 300rpm.(Fig. 2). But the delignification rate was slowed down during the late stage of cooking, compared with the early stage, and the consumption of oxygen was decreased simultaneously.(Fig. 3). The oxygen content in cooking liquor was increased cosequently and kept constant at various levels during the late stage.(Fig. 2).
Therefore, it needed a high agitation rate to compensate for the rapid consumption of oxygen during the early stage of delignification. But the agitation rate could be decreased considerably on the late stage.(Fig. 4).
This phenomenon was confirmed by investigating the correlation of the oxygen pressure, instead of the agitation rate, to the delignification.(Fig. 5).View full abstractDownload PDF (1271K) -
Takamasa Kubo, Jun Hosokawa, Takeshi Kobayashi1987 Volume 41 Issue 4 Pages 349-354
Published: April 01, 1987
Released on J-STAGE: October 27, 2010
JOURNAL FREE ACCESSThe fiber characteristics (fiber length, specific surface area, etc.) of alkaline sulfite chemithermomechanical pulp (Na2SO3+NaOH-CTMP) obtained from Giant Leucaena wood were measured and compared with those of thermomechanical pulp (TMP) and chemithermomechanical pulp (Na2SO3-CTMP).
The weighted average fiber length of Na2SO3+NaOH-CTMP was 0.75mm, which was longer than those of TMP (0.53mm) and Na2SO3-CTMP (0.55mm).
The specific surface area increased in the order TMP (4.5m2/g)<Na2SO3-CTMP (5.2m2/g)<Na2SO3+NaOH-CTMP (7.8m2/g). The large surface area of Na2SO3+NaOH-CTMP can be ascribed to the formation of fibrils and films-like particles on the fiber surface. The degree of internal fibrillation was higher in Na2SO3+NaOH-CTMP than in TMP or in Na2SO3-CTMP.
The high sheet strength of Na2SO3+NaOH-CTMP can be explained on the basis of the development of internal and external fibrillation by the addition of NaOH.View full abstractDownload PDF (1440K) -
1987 Volume 41 Issue 4 Pages 355-356
Published: April 01, 1987
Released on J-STAGE: October 27, 2010
JOURNAL FREE ACCESSDownload PDF (252K)
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