• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.4
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• pp.52-57
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• 2009

Soda and kraft pulping experiments were carried out in order to investigate the pulping characteristics of bamboo grown in Vietnam. The merit of kraft pulping was not observed for bamboo pulping from the viewpoint of delignification and screened pulp yield. The improvements of delignification during soda and kraft pulping of bamboo were observed by the addition of AQ. The bamboo pulp leaded the bulkier structure than those made from SwBKP and HwBKP. The average fiber length was 1.62mm which is shorter than those of SwBKP, but longer than those of HwBKP. It was found that the physical properties of bamboo pulp sheet could be varied by the pulping method, cooking condition, AQ addition, bleaching and refining etc.

• Journal of the Korean Wood Science and Technology
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• v.20 no.1
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• pp.51-59
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• 1992

The acetylation of papermaking pulp fiber(SwBKP, SwUKP, HwBKP and HwBCTMF) is carried out to modify the characteristics of pulp and paper. The effects of the addition of acetylated pulp on the filler retention and paper properties were investigated. The acetylation depended upon pulp type and the content of short fiber and fines. The addition of acetylated SwBKP did not deteriorate the retention of clay, talc and calcium carbonate, while the retention of titanium dioxide was increased with the addition of 20% and above. The brightness opacity, air permeability and tear strength were improved, but water resistance, burst strength and folding endurance were decreased by the addition of acetylated SwBKP and SwUKP. The tensile strength of SwBKP was increased until 20% of acetylated pulp is added, and then decreased. The tensile strength of SwUKP, however, was not changed until the acetylated pulp of 25% is added. The dimensional stability was improved by the addition of acetylated pulp and showed the different response to SwBKP and SwUKP.

• The Korean Journal of Food And Nutrition
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• v.6 no.1
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• pp.31-36
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• 1993

Strawberry pulp was separated into serum and insoluble pulp by centrifugation and the serum was concentrated in vacuo to five folds at 55~58$^{\circ}C$ and 30~60mmHg. Concentrated strawberry pulp was prepared by mixing of concentrated serum and insoluble pulp. To evaluate the quality changes of straw-berry pulp, color, physicochemical and sensory properties were analyzed after concentration and during 18 weeks storage at -18'2. The results obtained from the study were as follows : during 18 weeks storage at - l8$^{\circ}C$, soluble solid, browning, reducing sugar content were increased and total anthocyanin, vitamin C, apparent viscosity were decreased. The result of sensory evaluation indicated that texture of concentrated pulp was inferior to that of control but flavor, color intensity and overall acceptance were not different from each other.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04b
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• pp.232-238
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• 1999

The reinforcement of wheat straw pulp sheets with softwood kraft was studied, with special emphasis on the impact of softwood kraft beating and the proportion softwood kraft in straw pulp. the reinforcement was evaluated by measuring the tensile stiffness sand in-plane fracture behavior of samples. the results were compared with a mechanical pulp (TMP) and with a hardwood birch kraft, both reinforced with the same softwood kraft. Wheat straw pulp forms strong interfiber bonds. Therefore, its tensile stiffness and tensile strength are larger than TMP used. In-plane tear tests showed that a pure wheat straw pulp sheet has low fracture energy and correspondingly a narrow fracture process zone. The fracture energy of the reinforced straw sheets was found to increase linearly with the proportion of both unbeaten and beaten softwood pulps.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.4
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• pp.16-20
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• 2013

Yellow poplar grown in Korea and imported eucalyptus were compared their kraft pulping characteristics and evaluated the replacing possibility of eucalyptus by yellow poplar. Difference between yellow poplar and eucalyptus were investigated in chemical composition and fiber morphology. Yellow poplar kraft pulp resulted in the higher yield, longer fiber length and thicker fiber, and higher pulp strength than that of eucalyptus. More xylan survived in eucalyptus than yellow poplar during kraft pulping, which led to similar pulp yield even though polysaccharides in Eucalyptus was 4.5% less than in yellow poplar. Longer and thicker yellow poplar pulp fiber resulted in better beating response and pulp strength properties.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.8
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• pp.1204-1209
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• 2012

To diagnose dental pulp vitality, electric pulp tester has been widely used, which is a method to test condition of nerve. However, especially in the case of patients with trauma, nerve desensitization could temporarily occur even though nerve might be recovered by blood flow within the pulp later, which implies that blood flow in dental pulp is also an important factor for diagnosing vitality. This paper described the development of a probe that relatively measured blood flow in dental pulp using photoplethysmography (PPG). The probe emits four different wavelength light sources including three visible and an infrared light. We tested which light source detect sensitively the blood flow in dental pulp. As a result, green light had the largest peak to peak voltage and the power spectrum among different wavelengths.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.720-723
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• 2003

Electric stimulation of teeth is used for assessing pulp vitality. Because of very high and wide range of impedance of the enamel, electric pulp testers use high voltage, high output impedance and alternative current source. Most pulp testers use voltage stimulation method and their stimulating threshold levels significantly depend on each individual. Therefore, a constant current stimulator is necessary to minimize the effect of wide variation in enamel thickness. In this study, we constructed a constant current source type of pulp tester with the maximum current of 150 uA.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.5
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• pp.25-29
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• 2001

Dimethyldioxirane (DMD), which is a source of active oxygen, is effective agent that can be used in chemical pulp bleaching. In this study, delignification of kraft bagasse pulp has been carried out by using DMD. The effect of the applied charge of DMD (as active oxygen) and pH of the delignification medium were studied. The optimum conditions of the applied DMD charge and pH of the delignification reaction were achieved at pH range from 8~9, 2% of DMD (as active oxygen) and the rest of delignification reaction conditions were $25^{\circ}C$, 60 min, and 12% pulp consistency. The development of brightness per unit kappa number removal (ΔBrightness/ Δ Kappa number) has highest value at the optimum condition. The study showed that the reactivity of kraft bagasse pulp be enhanced to wards alkaline hydrogen peroxide bleaching by pulp treatment with DMD.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.586-586
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• 2003

In the infected immature tooth with periapical involvement, the pulp is considered to hardly exist in the canal and periapical area. Such a tooth receives apexification procedure, because revascularization of the pulp chamber is in principle not expected. Apexification is beneficial to induce further development of an apex to close the foramina, but does not promote the thickness of the entire canal wall dentin. It may be possible for the pulp to be only partially necrotic and infected when an extremely large communication from the pulp space to the periapical tissues exists with a very young tooth. If this were the case, vital pulp in the apical part of the canal could proliferate new pulp into the coronal pulp space by the successful removal and disinfection of the necrotic infected coronal pulp.(omitted)

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.04a
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• pp.321-326
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• 2007