• Title/Summary/Keyword: Fiber addition ratio

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Effects of Increase in Ratio of Phenolic Hydroxyl Function on Carbon Fiber Surfaces by Anodic Oxidation on Mechanical Interfacial Bonding of Carbon Fibers-reinforced Epoxy Matrix Composites (양극산화 처리에 따른 탄소섬유 표면의 페놀릭 하이드록실 관능기 비율의 증가가 에폭시기지 복합재료의 기계적 계면결합 특성에 미치는 영향)

  • Kim, Dong-Kyu;Kim, Kwan-Woo;Han, Woong;Song, Bhumkeun;Oh, Sang-Yub;Bang, Yun Hyuk;Kim, Byung-Joo
    • Applied Chemistry for Engineering
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    • v.27 no.5
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    • pp.472-477
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    • 2016
  • We studied the effects of anodic oxidation treatments of carbon fibers on interfacial adhesion of the carbon fibers-reinforced epoxy matrix composites with various current densities. The surface of treated carbon fibers was characterized by atomic force microscope (AFM), field emission-scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The interlaminar shear strength (ILSS) of the composites was determined by a short beam shear test. This result showed that both the roughness and oxygen group of the carbon fibers surface increased in proportion to the current density. After anodic-oxidation-treated, the ILSS also increased as a function of the current density. In addition, the proportional relationship between ILSS and phenolic hydroxyl group was confirmed. The ILSS of the CF-2.0 sample increased by 4% compared to that of the CF-AS sample, because the anodic oxidation treatment increased the oxygen group and roughness on the carbon fibers surface, which leading to the improvement of the interfacial adhesion of the carbon fibers-reinforced epoxy matrix composites. Among these, the phenolic hydroxyl group which has the proportional relationship with ILSS is found to be the most important factor for improving the interfacial adhesion of the carbon fibers-reinforced epoxy matrix composites.

The Flora of Vascular Plants in Mt. Gariwang Protected Area for Forest Genetic Resource Conservation, South Korea (가리왕산 산림유전자원보호구역의 관속식물상)

  • Byun, Jun Gi;Jang, Jeong Won;Yang, Jong Cheol;Lee, You Mi;Jung, Su Young;Ji, Sung Jin;Jang, Jin;Lee, Hye Jeong;Hwang, Hee Suk;Oh, Seung Hwan
    • Korean Journal of Plant Resources
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    • v.26 no.5
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    • pp.566-588
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    • 2013
  • This study was carried out to investigate the vascular plants of the Mt. Gariwang (1,560.6 m) Protected Area for Forest Genetic Resource Conservation. The vascular plants collected 5 times (from May 2011 to October 2012) consisted of total 529 taxa; 89 families, 272 genera, 458 species, 3 subspecies, 62 varieties and 6 forms respectively. Among them, 22 taxa of Korean endemic plants and 30 taxa of Korean rare plants were investigated in addition to 144 taxa of specially designated plants announced by the Ministry of Environment of Korea. Naturalized plants were 15 taxa, therefore naturalized ratio was 2.83%. 529 taxa listed consists of 178 taxa (33.6%) of edible plants, 144 taxa (27.2%) of medicinal plants, 163 taxa (30.8%)of pasture plants, 68 taxa (12.8%) of ornamental plants, 20 taxa (3.8%) of timber plants, 8 taxa (1.5%) of fiber plants, respectively.

Effect of tannins and cellulase on growth performance, nutrients digestibility, blood profiles, intestinal morphology and carcass characteristics in Hu sheep

  • Zhao, M.D.;Di, L.F.;Tang, Z.Y.;Jiang, W.;Li, C.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.10
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    • pp.1540-1547
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    • 2019
  • Objective: This study was conducted to evaluate the effects of tannins and cellulase on growth performance, nutrient digestibility, blood profiles, intestinal morphology, and carcass characteristics in Hu sheep. Methods: A total of 48 three-month-old meat Hu sheep ($25.05{\pm}0.9kg$) were blocked based on body weight, and randomly allotted to 4 treatments with 3 replicates of 4 sheep each. The experiment lasted for 80 d, and dietary treatments were as follows: i) CON, control diet; ii) TAN, CON+0.1% tannins; iii) CEL, CON+0.1% cellulase; iv) TAN+CEL, CON+0.1% tannins and 0.1% cellulase. Results: Compared with CON, CEL, and TAN+CEL had greater (p<0.05) final body weight (FBW) and average daily gain but lower (p<0.05) feed conversion ratio, while FBW of TAN+CEL was lower (p<0.05) than that of CEL. The apparent total tract digestibility (ATTD) of dry matter in TAN, CEL, and TAN+CEL groups were higher (p<0.05) than that in CON. CEL and TAN+CEL groups had greater (p<0.05) ATTD of crude fiber compared with TAN and CON, while TAN group had lower (p<0.05) ATTD of crude protein than other treatments. TAN, CEL, and TAN+CEL groups increased (p<0.05) serum globulin and alkaline phosphatase but decreased (p<0.05) albumin/globulin. Serum total protein was greatest for TAN+CEL, intermediate for TAN and CEL and least for CON (p<0.05). TAN+CEL group increased (p<0.05) dressing percentage compared with CON, while the backfat thickness of CEL was lower (p<0.05) than that of CON. The villus height of jejunum and ileum in CEL and TAN+CEL groups were greater (p<0.05) than that in CON, and the crypt depth and villus height: crypt depth of jejunum were increased (p<0.05) in TAN, CEL, and TAN+CEL groups. Conclusion: The addition of tannins and cellulase together promoted nutrient digestion, liver protein synthesis and intestinal development and thus improved growth performance and carcass characteristics.

Effects of the Exercise Training on Aging Heart in Rat I. Long Term Endurance Exercise (운동훈련이 흰쥐 노화심근에 미치는 영향 I. 장기간 지구력 운동 훈련)

  • 박원학;이상선;이용덕
    • Biomedical Science Letters
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    • v.2 no.1
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    • pp.71-90
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    • 1996
  • There is considerable current interest in the effect of regular vigorous exercise and in particular endurance-running as a possible measure in improving myocardial function. Some data indicate that the aging heart may actually suffer from vigorous endurance exercise. On the contrary appropriate exercise in aged animals improves myocardial function and aerobic energy metabolism. So far there is relatively little data to indicate that endurance exercise is in fact beneficial in improving myocardial function or damaging to heart of aged animals. The present investigation aimed to study the possible effect of a long range treadmill training program on the heart in aging rats. Male rats aged 3, 10, and 20 months were divided at random into a control (sedentary) and an exercise group. The training group was exercised for 5 days a week on an automated treadmill for 20minutes at 18m/min over a period of 5 months. The exercise regimen of our experiments did not cause any significant changes in the tissues and ultrastructural as com-pared with sedentary age-matched control. Tissues and ultrastructures of myocardial cells in trained group aged 8 months are intact and well organized as well as sedentary control group. Age associated tissue and ultrastructural changes of trained group aged 15 months included : an increase in transformed mitochondria, vacuoles, lysosomes, lipid droplets and early lipofuscin. But the trained heart did not show significant difference in tissue and ultrastructural properties from those of sedentary controls. Endurance-trained group aged 25 months showed significant qualitative tissue and ultrastructural difference as compared with age-matched controls. In addition to those found in 25 months control group, focal necrosis, myofibril fraying, hypercontraction band, seperation of intercalated discs, degenerating nucleus and infiltration of collagenous fiber into myocyte were noted in trained 25 months group. The stereological examination of the mi-crographs disclosed no significant difference in the myoflbril, mitochondrion, sarcotubule and in-terstitium volume density and surface density of mitochondrial cristae and numerical density of mitochondria between trained and control group aged 8 and 15 months. In the trained 25 months group, significant increase in volume density of interstitium, lipofucsin granule were shown as compared to untrained age-matched control. On the other hand, significant decrease in mitochondrion volume density was shown. The myofibril volume density did not differ between trained and control group although trained group showed slight increase. From the data obtained a reduced mitochondria/myofibrils ratio was found in trained rat heart aged 25 months and there was no difference between trained and control rat aged 15 months. But a slight but not significant increase was found in the trained group aged 8 months as compared with same age control group. Such increase in the ratio in young animals is considered to be of great importance to cardiac pumping and adaptability. Whereas such adaptations don't seem to occur in aged heart muscle. This study proposed that repeated endurance exercise do not cause any significant qualitative and quantitative ultrastructural change of heart muscle in young(3months) and adult (10months) suggesting that the heart is able to adapt to the exercise. On the contrary, the repeated endurance exercise stress may actually induce degenerative changes in the aged heart muscle(20months).

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Quality Characteristics of Bread with Dried Persimmons Hot-Water Extracts (곶감 열수추출물을 첨가한 식빵의 품질특성)

  • 문혜경;한진희;김준한;김귀영;강우원;김종국
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.4
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    • pp.723-729
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    • 2004
  • To develop foods using dried persimmon, hot-water extracts of dried persimmons were added into strong wheat flour in the ratio of 10, 20, 30, and 40% and the quality characteristics of baked products were investigated. The proximate compositions of dried persimmons hot-water extracts were 70.37% of moisture, 1.72% of crude protein, 0.18% of crude lipids, 1.99% of crude ash and 4.37% of crude fiber, respectively. With increasing the addition of dried persimmons hot-water extracts, moisture content of the added breads was increased to 47.20% from 41.12% of non-added bread and water activity to 0.576 from 0.495. Water binding capacity of the added dried persimmons hot-water extracts rasied weight of the bread but decreased specific volume. In the hunter's color values the more dried persimmons hot-water extracts was added, the lower L vaules we, and the higher a and b values we. In the texture property, the addition of dried persimmons hot-water extracts increased hardness, gumminess and chewiness, while decreased adhesiveness and fracturability. Judging from texture, taste and overall acceptability of the product, recommended substitution level for hot-water extracts of dried persimmons in bread was 30% or less.

Feed Value of the Different Plant Parts of Main Forage Rice Varieties (사료용 벼 주요 품종의 수확부위 별 사료가치)

  • Ahn, Eok-Keun;Won, Yong-Jae;Kang, Kyung-Ho;Park, Hyang-Mi;Jung, Kuk-Hyun;Hyun, Ung-Jo;Lee, Yoon-Sung
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.67 no.1
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    • pp.1-8
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    • 2022
  • In order to manufacture feed suitable for consumer use and provide feed value information, we analyzed the feed components of the four main forage rice varieties by plant parts harvested 30 days after heading. The contents of the six feed ingredients were significantly different (p<0.05) among harvested parts. In the panicle, the crude protein (CP) (6.97%) and lignin (3.11%) were the highest, while the crude ash (CA) and neutral detergent fiber (NDF) contents were significantly lower, resulting in a total digestible nutrient (TDN) content of 77.29%, which is higher than that of the stem (64.82%) and leaf blade and sheath (LBS) (63.57%) (p<0.05). In contrast, the content of crude fat (CF) did not differ significantly among parts (p<0.05). In panicles from 'Jonong', 'Nokyang' and 'Yeongwoo', the TDN content of each cultivar was 78.48-79.07%, with no significant difference among the varieties. In 'Mogwoo' (Mw), the CP content was 8.70%, which was much higher than that of other varieties (p<0.05). In particular, the Mw TDN content was slightly lower in the panicle (72.95%) but higher in the stem (75.37%) and LBS (66.49%) than in the other varieties. The CA, NDF, acid detergent fiber (ADF), and lignin contents were also very low compared to other varieties; therefore, the feed value of the stem and LBS was excellent. In addition, the total dry matter weight (DMW) was 123 g per hill, which was much higher than 82-105 g per hill for other varieties. The distribution of DMW by part was LBS (56.9 g), stem (36.8 g), and panicle (29.3 g), and because the parts, except the panicles, were much higher than the 43-57% of other varieties (grain straw ratio: 76%), rice straw is advantageous in terms of quantity and feed value when used as forage on farms. The relative feed value (RFV) of the four cultivars ranged from 86.79-403.74 across all parts, and hay of grade 3 or higher with an RFV of 100 or more increased with delayed heading in both stems and LBS. This is due to the accumulation of starch into grains during ripening, which supports the observation that the RFV of the early flowering 'Jonong' and 'Nokyang' panicles increased.

Effects of Added Vegetable Oils on In vitro Formation of Fatty Acid Soaps and Fermentation Characteristics and NDF Disappearance Rate (식물성유 첨가가 In vitro 발효성상, NDF 소실율 및 지방산염 형성에 미치는 영향)

  • Kim, D.I.;Choi, J.R.;Lee, Y.H.;Lee, J.K.;Chung, T.Y.
    • Journal of Animal Science and Technology
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    • v.46 no.3
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    • pp.355-372
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    • 2004
  • In vitro experiments were conducted to determine the formation of fatty acid soaps (FAS) and neutral detergent fiber (NDF) disappearance rate. The substrates were a basal alfalfa hay containing 1) no oil, 2) 10% soybean oil, 3) 10% com oil, on a weight basis. All the substrates were incubated in triplicate for 0, 3, 6, 12, 24 and 48h in each experiment. After the incubation in the first experiment serum bottles (6oml) were analyzed for nonesterified, esterifed and fatty acid soaps contents. The serum bottles (120mI) from the second experiment were analyzed for pH, $NH_3-N$ and VFA concentration, and dry matter and NDF disappearance rate. pH decreased and the concentration of NH3-N increased significantly with longer incubation time (P<0.0001). The disappearance rates of dry matter and NDF significantly varied with feed, incubation time and oils (P<0.05). The molar concentration of total VFA increased and proportion of acetate significantly decreased with incubation time (P<0.0001), but the proportion of propionate significantly increased with longer incubation time (P<0.0001). Addition of oils to diet lowered the ratio of acetate:propionate (P<0.05). The esterified fatty acids (EFA) decreased with increasing incubation time (P<0.0001), and nonesterified fatty acids (NEFA) increased due to lipolysis of EFA, NEFA then reacted with cations to increase formation of FAS. The formation of FAS increased significantly at 48h of incubation time (P<0.0001). Especially, formation of stearic acid soaps was 27.5 and 32.5 folds with soybean oil and com oil supplements, respectively, by 48h of incubation time (P<0.0001). Alfalfa hay had higher cation contents, particularly Ca, which react with NEFA and FAS can be formed with longer incubation time. Saturated fatty acids had a higher proportion of FAS than did unsaturated fatty acids, suggesting that the former may react more extensively with cations. FAS contents increased with increasing chain length of the fatty acids. Since added vegetable oils fonned FAS, it might decrease negative effects on in vitro fermentation characteristics and NDF disappearance rate.

Physicochemical Properties, Free Sugar and Volatile Compounds of Korean Citrons Cultivated in Different Areas (산지별 유자의 이화학적 특성, 유리당 및 향기성분)

  • Lee, Soo-Jung;Shin, Jung-Hye;Kang, Min-Jung;Jeong, Chang-Ho;Ju, Jong-Chan;Sung, Nak-Ju
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.1
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    • pp.92-98
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    • 2010
  • Physicochemical properties, free sugar and volatile flavor compounds of citrons harvested in different cultivation areas, such as Geoje, Goseong, Goheung, and Namhae, were analyzed and compared. Total weight of citron, ranging from 107.97 g to 154.86 g, was significantly different according to producing area. Weight ratio of flesh to whole citron was higher than one of peel in citron produced from Geoje, Goheung-improved, or Namhae-native. Citron size was the highest in Namhae-native citron, but the color of peel was significantly the higher in Goheung-native and its improved citron. In the peel of citron, hardness of citron produced from Geoje was the strongest (2337.13 $cm/kg^2$) whereas citron produced from Goseong (1592.38 $cm/kg^2$) showed the softest hardness. Moisture content was 85.35~87.81 g/100 g and ash was contained below 0.8 g/100 g in flesh of all samples. Although crude fiber content in Geoje ctiron was significantly the lowest in the peel, peel was 1.88~2.60 times higher than flesh. The order of sugar content seemed to be fructose> glucose> sucrose in all citrons, and content of fructose or glucose was higher in peel than flesh. Content of total sugar was 8.44~12.19 g/100 g in citron, and contents of improved citrons from Goheung and Namhae were significantly higher than those of native citrons. In addition, major volatile compounds were dl-limonene (59.52~74.30%) and $\gamma$-terpinene (5.60~7.88%) among 15 kinds of volatile compounds identified from citron peel. These results suggested that physicochemical properties and volatile flavor compounds of citrons showed some differences with regard to producing areas.

Relationship between intake of soft drinks and current prevalence of adult atopic dermatitis: based on the Korea National Health and Nutrition Examination Survey data (2015-2016) (탄산음료 섭취와 성인 아토피 피부염 진단 및 현재 유병과의 관련성: 국민건강영양조사(2015-2016년) 자료를 바탕으로)

  • Kim, Hye Won;Kim, Ji-Myung
    • Journal of Nutrition and Health
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    • v.54 no.5
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    • pp.501-514
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    • 2021
  • Purpose: The purpose of this study was to provide basic data for the management of atopic dermatitis (AD) in adults by analyzing the relationship between AD and intake of soft drinks in adults. Methods: This study was conducted on 5,931 adults aged 19 to 64 who completed the food frequency questionnaire (FFQ) for participants in the Korea National Health and Nutrition Examination Survey VII-3 and VII-1. Subjects were divided into an AD-diagnosed group and a non-AD group according to the diagnosis of AD. In addition, the group diagnosed with AD was divided into a 'symptom-AD' group and a 'no symptom-AD' group. The amount, frequency of intake, and nutritional status of soft drinks were analyzed using the FFQ. Results: Compared with the nutrient intake per 1,000 kcal of energy consumption, fat intake was higher in the AD-diagnosed group than in the non-AD group, and carbohydrate, dietary fiber, calcium, phosphorus, iron, potassium, vitamin A, thiamin, and vitamin C were lower in AD-diagnosed group. The daily intake of soft drinks and the percentage of 'more than 0.5 servings per day' were also higher in the AD-diagnosed group than in the non-AD group. Also, the frequency of the intake of soft drinks was significantly higher in the AD-diagnosed group than in the non-AD group. The odds ratio of AD symptoms due to the intake of soft drinks increased 2.6 times when the intake was 'less than 0.5 serving per day'. Conclusion: AD in adults appears to be related to malnutrition and excessive consumption of soft drinks, and the current prevalence of AD symptoms may also be related to the intake of soft drinks. Based on these results, we suggest that one of the ways to manage AD in adults would be to limit their intake of soft drinks.

Studies on the Pulping Characteristics of Larchwood (Larix leptolepis Gordon) by Alkaline Process with Additives (첨가제(添加劑) 알칼리 법(法)에 의한 일본 잎갈 나무의 펄프화(化) 특성(特性)에 관(關)한 연구(硏究))

  • Lim, Kie-Pyo;Shin, Dong-Sho
    • Journal of the Korean Wood Science and Technology
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    • v.7 no.2
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    • pp.3-30
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    • 1979
  • Larch ($\underline{Larix}$ $\underline{leptolepis}$ GORDON), one of the major afforestation species in Korea in view of its growing stock and rate of growth, is not favored as a raw material for pulp due to its low yield of pulp and difficulties with bleaching arising from the high content of extractives in wood, and the high heartwood ratio and the active phenolics, respectively. The purpose of this study is to investigate the characteristics of firstly pulping with various additives of cellulose protector for the yield of pulp, and secondly bleaching with oxygen for chlotination-alkali extraction of five stage-sequence to reduce chlorine compounds in bleaching effluents. The kraft cooking liquor for five age groups of larchwood was 18 percent active alkali with 25 percent sulfidity and 5 : 1 liquor-to-wood ratio, and each soda liquor for sap-and heart-wood of the 15-year-old larchwood was 18 percent alkali having one of the following cellulose protectors as the additive; magnesium sulfate ($MgSO_4$, 2.5%), zinc sulfate ($ZnSO_4$, 2.5%), aluminium sulfate ($Al_2(SO_4)_3$, 2.5%), potasium iodide (KI, 2.5%), hydroquinone (HQ, 2.5%), anthraquinone (AQ, 0.1%) and ethylene diamine (EDA, 2.5%). Then each anthraquinone-soda liquor for the determination of suitable cooking condition was the active alkali level of 15, 17 and 19 percent with 1.0, 0.5 and 0.1 percent anthraquinone, respectively. The cooking procedure for the pulps was scheduled to heat to 170$^{\circ}C$ in 90 minutes and to cook 90 minutes at the maximum temperature. The anthraquinone-soda pulps from both heartwood and sapwood of 15-year-old larchwood prepared with 0.5 percent anthraquinone and 18 percent active alkali were bleached in a four-stage sequency of OCED. (O: oxygen bleaching, D: chlorine dioxide bleaching and E: alkali extraction). In the first stage oxygen in atmospheric pressure was applied to a 30 percent consistency of pulp with 0.1 percent magnesium oxide (MgO) and 3, 6, and 9 percent sodium hydroxide on oven dry base, and the bleached results were compared pulps bleached under the conventional CEDED (C: chlorination). The results in the study were summarized as follows: 1. The screened yield of larch kraft pulp did not differ from particular ages to age group, but heartwood ratio, basic density, fiber length and water-extractives contents of wood and the tear factor of the pulp increased with increasing the tree age. The total yield of the pulp decreased. 2. The yield of soda pulp with various chemicals for cellulose protection of the 15-year-old larchwood increased slightly more than that of pure soda pulp and was slightly lower than that of kraft pulp. The influence of cellulose protectors was similar to the yield of pulps from both sapwood and heartwood. The effective protectors among seven additives were KI, $MgSO_4$ and AQ, for which the yields of screened pulp was as high as that of kraft pulp. Considering the additive level of protector, the AQ was the most effective in improving the yield and the quality of pulp. 3. When the amount of AQ increased in soda cooking, the yield and the quality of the pulp increased but rejects in total yield increased with decreasing the amount of active alkali from 19 to 15 percent. The best proportion of the AQ seemed to be 0.5 percent at 17 percent active alkali in anthraquinone-soda pulping. 4. On the bleaching of the AQ-soda pulp at 30 percent consistency with oxygen of atomospheric pressure in the first stage of the ODED sequence, the more caustic soda added, the brighter bleached pulp was obtained, but more lignin-selective bleaching reagent in proportion to the oxygen was necessary to maintain the increased yield with the addition of anthraquinone. 5. In conclusion, the suitable pulping condition for larchwood to improve the yield and quality of the chemical pulp to the level for kraft pulp from conventional process seemed to be. A) the selection of young larchwood to prevent decreasing in yield and quality due to the accumulation extractives in old wood, B) the application of 0.5 percent anthraquinone to the conventional soda cooking of 18 percent active alkali, and followed, C) the bleaching of oxygen in atmospheric pressure on high consistency (30%) with 0.1 percent magnesium oxide in the first stage of the ODED sequence to reduce the content of chlorine compounds in effluent.

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