• 펄프종이기술
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• 제30권2호
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• pp.85-95
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• 1998

Traditionally, Hanji had been made only with the bast fiber of paper mulberry (Broussonetia kazinoki). Nowadays, Hanji has been made mainly in the mixed forms of paper mulberry bast fiber and waste paper, and consequently it has raised many problems using them. This study was carried out to investigate the characteristics of Hanji mixed with paper mulberry bast part and whole stalk pulps. Hanjis made from the solfomethylated pulp were shown higher brightness and sheet strengths than those from alkali and alkali-hydrogen peroxide pulps. The brightness of solfomethylated pulp was found to be high enough not to need additional bleaching. The sheet formations were improved as the increase of whole stalk pulp contents, while the sheet strengths were decreased. In the physical properties of the Hanji mixed with bast part and whole stalk pulps, the handsheet strengths were decreased as the increase of the whole stalk pulp contents. The tensile strength and folding endurance of the Hanji containing 40∼60% of whole stalk pulps were higher as compared to the others.

• 펄프종이기술
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• 제31권3호
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• pp.10-18
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• 1999

The influence of simple electrolyte or anionic trashes on cationic starch adsorption was examined using deinked pulp and bleached thermomechniical pulp. Adsorbed amounts of cationic starches increased slightly , then decreased abruptly as the concentration of simple electrolyte increased. This phenomenon was discussed based on the compression of electrical double layer and conformation change of starch molecules. Also, the effect of the type of simple electrolytes on starch adsorption was examined and discussed. Addition of sodium slilicate increased starch adsorption since it increased surface charge density of fibers. On the other hand, addition of kraft lignin decreased cationic demand of the pulp slurries and adsorbed amounts of cationic starches. Nonionic surfactant did not show any significant effect on the cationic demand of pulp slurries. When simple electrolytes were added to the stock , grater adsorption or cationic starches was obtained with starches of lower degree of substitution . On t도 other hand, amount of adsorbed starches decreased for lower DS starches when the concentration of anionic trashes increased.

• 대한치과의사협회지
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• 제10권1호
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• pp.15-21
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• 1972

백서의 전치를 주기적으로 절제후 치수내의 LDH isoenzyme을 전기영동법으로 분리하고 그의 활성도를 측정하여 정상과 비교관찰한바 다음과 같은 결론을 얻었다. 1. 정상치수내에서 5개의 LDH isoenzyme의 존재를 확인하였다. 2. LDH 활성도는 주기적으로 절제한 치아의 치수가 정상치수에 비해 훨씬 증가하였다. 3. 치아를 주기적으로 절제함으로써 치수내 LDH isoenzyme의 Pattern을 변화시킬 수가 있다.

• 펄프종이기술
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• 제38권3호
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• pp.7-12
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• 2006

The pore structure of paper was modified by the application of the blending of pulp, refining, and filler particle size and ash content. It was conformed that the reflectivity of paper can be modified by the combination of the above parameters. It was also found that the change of reflectivity of paper was greatly dependent on the pore structure, such as average pore size, pore size distribution and porosity. The average pore size was decreased with addition of HwBKP, but the smallest average pore size was obtained from the addition of 80% HwBKP Refining of pulp decreased both average pore size and the reflectivity of paper. The pore size distribution of filled paper can be varied by the combination of filler particle size and ash content

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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• pp.153-159
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• 2006

Red algae were used to make bleached pulp, from which paper handsheet samples were made. Red algae consists of rhizoidal filaments, epidermal tissues whose color were reddish, mucous carbohydrates, and other minor elements. Rhizoidal filaments of high brightness were obtained after extracting out mucous carbohydrates, and bleaching the remainder by using bleaching chemicals. The sizes and shapes of several rhizoidal filaments (or red algae pulp) from different red algae species were examined, and their handsheet properties were compared. Transparent and transluscent high density paper samples were made without applying refining process from the red algae pulp. White paper samples with good printability and excellent formation were made. We are developing pilot scale pulping and papermaking facilities at this time.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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• pp.167-172
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• 2006

High-yield Pinus radiate kraft pulps with various Kappa number were produced from flow-through laboratory pulping. The samples were prepared and scanned using a rapid scan photoacoustic Fourier transform infrared (PAS-FTIR) spectrometer. A partial-least-squares (PLS) model was established based on the spectral data collected at different mirror velocities. The model was used to predict the Kappa number of the pulps and its robustness was statistically evaluated. The outcomes indicate that the PLS model can be used to predict the Kappa number of Pinus radiata kraft pulps with a high degree of accuracy provided that the moving mirror velocity is ${\leq}\;0.5cm/s$.

• 펄프종이기술
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• 제39권5호
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• pp.39-44
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• 2007

In order to utilize unsorted ONP, which contains leaflets (printed coated papers), as a raw material to produce pulp mold, optimum conditions for repulping were investigated with the pilot Helico pulper at Centre Technique du Paper (CTP), France. Two major process factors were focused: repulping concentration and rotor speed. Repulping at a higher concentration showed more rapid defibering kinetics. Increasing the rotational speed of rotor at the optimum repulping concentration accelerated the defibering kinetics while it also led to higher fines generation and faster decrease in drainage property of the produced pulp. Hence, an alternative way was suggested: starting repulping at a conventional rotor speed and then accelerating the rotor speed for the last minute(s) of repulping.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.391-394
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• 2006

Studied that the relationship between the charge density of PAC and its alkalinity, as well as the influences of PAC in paper sizing. Study results showed that PAC with higher charge density brought higher sizing degree when the same amount of $Al_{2}O_{3}$ content was dosed. However, there was no direct relationship between PAC charge density and its alkalinity, and higher PAC alkalinity can't improve its charge density. It was also found that the admixture (PPAC) of polyamine and PAC had higher charge density than PAC. The effects of PPAC on DRS and RAKD sizing were better than PAC sizing, when dosage and other sizing condition were the same.

• 펄프종이기술
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• 제44권3호
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• pp.63-69
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• 2012

The rice husk is one of the major agricultural residue in KOREA. In this paper, the effects of various pulping conditions on the properties of rice husk pulp and handsheets made of rice husk fiber were evaluated in order to utilize the rice husk as an alternative source for wood pulp. Two typical alkali pulping, such as soda pulping and Kraft pulping were applied with various conditions of the pulping processes. The higher effective alkali and higher pulping temperature resulted in the higher efficiency in removal of lignin and ash, which leaded to the higher strength properties of handsheets made of rice husk fiber, but the lower yield of rice husk pulp. The better efficiency in production of rice husk pulp and the stronger handsheets were obtained by the Kraft pulping.

• Tribology and Lubricants
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• 제15권4호
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• pp.314-320
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• 1999

Friction and wear characteristics of phenolic resin-based friction materials reinforced with aramid pulp and potassium titanate were investigated using a pad-on-disk type friction tester. Friction characteristics such as friction stability, thermal stability, and wear rate varied according to the type of phenolic resins and the relative amount of aramid pulp and potassium titanate. The modified novolac resin-based friction materials showed better heat resistance and friction stability than those with the unmodified(straight) novolac resin. Compared with friction materials filled with potassium titanate or aramid pulp only, the friction materials reinforced with both aramid pulp and potassium titanate showed good friction stability and wear resistance. Increment of aramid pulp from 10 to 20 vol.% however, showed little difference in friction stability.