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Identification of Antioxidant Compound Derived from Methanolic Extract of Houttuynia Cordata (어성초 메탄올 추출물로부터 항산화 효능을 가진 활성물질의 확인)

  • Kim, Hyeji;Hwang, Heesung;Park, Sumin;Kang, Sungwook;Kim, Hyejeong;Hong, Sugyeong;Kim, Moon-Moo;Oh, Yunghee
    • Journal of Life Science
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    • v.27 no.7
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    • pp.796-804
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    • 2017
  • This study was carried out to evaluate the antioxidant effect of methanolic extract of Houttuynia cordata (HCME) and to identify a compound having antioxidant effect. The ethyl acetate fraction of HCME showed the highest antioxidant effect in organic solvent fractions. The fraction was then separated into 12 fractions by open column chromatography. Among these fractions, the fraction 10 (Fr. 10) with the highest antioxidant activity was isolated, and its antioxidant effect was evaluated by DPPH radical scavenging activity, reducing power, TBARS, cell viability, DNA oxidation and DCF fluorescence. The Fr. 10 at a $64{\mu}g/ml$ showed 60% of inhibitory effect similar to that of vitamin C at $10{\mu}g/ml$, compared with blank group. The Fr. 10 at $64{\mu}g/ml$ showed 264% of reducing power, compared with blank group. TBARS assay showed that the Fr. 10 at $64{\mu}g/ml$ had 35.5% of inhibitory effect similar to that of vitamin E at $1,000{\mu}g/ml$, compared with blank group. The Fr. 10 above $32{\mu}g/ml$ displayed cytotoxicity. However, it was observed that the Fr. 10, above $1{\mu}g/ml$ reduced DNA damage. DCF fluorescence assay showed that the Fr. 10 inhibited oxidative stress by $H_2O_2$ in a dose dependent manner. The compound of Fr. 10 was identified to be rutin whose molecular weight is 610 by the IR and LC-MS analyses. Therefore, these results suggest that the rutin of Fr. 10 could use as a natural antioxidant for development of cosmetics and functional foods.

Eotaxin mRNA Expression in Bronchial Mucosa of Patients with Asthma (천식 환자의 기관지 조직에서 Eotaxin mRNA 발현에 관한 연구)

  • In, Kwang-Ho;Cho, Jae-Yun;Kang, Sae-Yong;Lee, Sang-Youb;Shim, Jae-Jeong;Kang, Kyung-Ho;Yoo, Se-Hwa;Na, Young-Soon;Kim, Han-Gyum
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.4
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    • pp.697-704
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    • 1998
  • Background: Asthma is a chronic inflammatory disease of the airways characterized by a marked infiltration of eosinophils in the bronchial mucosa. Asthmatic bronchial mucosa produces many factors described as being chemotactic for inflammatory cells. IL-5, RANTES, and MCP-1 alpha are the chemotactic factors for eosinophils, but their roles are controversial. Recently eotaxin that is a potent eosinophil chemoattractant cytokine was detected in a guinea-pig model of allergic airway inflammation, and human eotaxin was cloned. Eotaxin is a specific chemoattractant for eosinophils, but its role in asthma is not confirmed. We examined the in vivo expression of eotaxin in bronchi of asthmatic patients. Methods : 11 asthmatics and 2 normal controls were enrolled. All subjects were underwent bronchoscopy with bronchial biopsies in 2nd or 3rd carina. RNA extraction from biopsy samples was done by acid-guanidium method. Semi-quantitaive RT-PCR was done for evaluation of eotaxin mRNA expression The extent of eosinophil infiltration was evaluated by counting the eosinophils in submucosa in HPF of microscope. Results : Eotaxin mRNA expressed in symptomatic, uncontrolled asthma. Steroid inhibited expression of eotaxin mRNA in asthma. Expression of eotaxin mRNA correlated with eosinophil infiltration in bronchial tissues. Conclusion: Expression of eotaxin mRNA increases in uncontrolled asthma and eotaxin is involved in the recruitment of eosinophils.

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Sludge reduction by Enzyme Pretreatment (효소 전처리를 통한 슬러지 저감)

  • 김정래;심상준;최수형;염익태
    • KSBB Journal
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    • v.19 no.2
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    • pp.93-97
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    • 2004
  • We investigate the effect of enzyme pretreatment using protease, carbohydrase, and lipase on improvement of sludge treatment efficiency by measuring SCOD and TCOD. The enzyme-pretreatment increases SCOD of excess sludge. In addition, the amount of sludge reduction during digestion, in terms of SCOD and TCOD, are enhanced by enzyme-pretreatment. Among pretense, carbohydrase, and lipase, pretense showed the best enhancement of the sludge treatment efficiency. Sludge digestion followed by ozone and enzyme treatments showed more effective sludge treatment when compared with ozone treatment alone. Therefore, we expect that enzyme pretreatment can be used as a useful tool for enhancing the sludge treatment efficiency.

Effect of Cordyceps ochraceostromat, Silkworm Cocoon, and Conjugated Linoleic Acid on the Quality and Storage Characteristics of Pork Sausage Manufactured by MDCM (Mechanically Deboned Chicken Meat) Recovered Protein (기계발골계육 회수단백질을 활용한 돈육 소시지의 품질 및 저장성 향상을 위한 동충하초, 누에고치 및 Conjugated Linoleic Acid의 첨가 효과)

  • Jin, Sang-Keun;Kim, Il-Suk;Kang, Suk-Nam;Hur, In-Chul;Choi, Seung-Yun;Kang, Sang-Ha;Yang, Han-Sul;Joo, Seon-Tea;Park, Gu-Boo
    • Food Science of Animal Resources
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    • v.30 no.2
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    • pp.243-251
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    • 2010
  • This study was conducted to investigate the effects of the addition of cordyceps ochraceostromat, conjugated linoleic acid (CLA) and silkworm cocoon on the quality and storage characteristics of pork sausage manufactured by MDCM (mechanically deboned chicken meat) recovered protein. The samples were divided into 5 groups (sausage made from pork ham; control, 40% of MDCM recovered protein to replace pork ham; T1, 40% of MDCM recovered protein to replace pork ham with 0.1% cordyceps ochraceostromat; T2, 40% of MDCM recovered protein to replace pork ham with 0.1% CLA; T3, and 40% of MDCM recovered protein to replace pork ham with 0.1% silkworm cocoon; T4). The control sample had a higher moisture and protein contents and lower fat content than the other samples during 4 weeks of storage at $4^{\circ}C$ The treatment samples had lower lightness and higher redness values than the control (p<0.05). Hardness, cohesiveness, gumminess and chewiness were significantly lower in the treatment samples than the control (p<0.05). All sausage samples showed a significant increase in thiobarbituric acid reactive substances (TBARS), volatile basic nitrogen, and total plate counts during the storage time (p<0.05). In addition, the MDCM treatment samples had higher TBARS values than the control, but the VBN value of the treatment samples was lower than the control after the 4 weeks storage period.

Studies on the Applications of TL and ESR Methods for the Detection of Spices, Berry Fruits and Pollen Extract Product (TL과 ESR 분석을 통한 일부 향신료, 장과류 및 화분가공추출물 검지 특성 연구)

  • Kim, Kyu-Heon;Son, Jin-Hyok;Kang, Yoon-Jung;Park, Hye-Young;Kwak, Ji-Young;Lee, Jae-Hwang;Park, Yong-Chjun;Jo, Tae-Yong;Lee, Hwa-Jung;Lee, Sang-Jae;Han, Sang-Bae
    • Journal of Radiation Industry
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    • v.7 no.1
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    • pp.69-74
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    • 2013
  • This study examined radiation detection characteristics of spices (cumin, caper and turmeric), other small fruits (hut-gae berry and boxthorn), and pollen extract product. Each samples were irradiated at dose of 1, 5, and 10 kGy and analyzed by the thermoluminescence (TL) and electron spin resonance (ESR) methods. To compare between non-irradiated and irradiated food, all samples were irradiated with $^{60}Co$ gamma-ray source. In TL analysis, most of samples could be applied to detect irradiated foods because of showing TL ratio above 0.1. The glow curves examined by TL method were estimated in the range of $150{\sim}250^{\circ}C$ in irradiated samples. In ESR measurements, the intensity of ESR signal (single-line) increased as the increase of irradiation dose. In particular, the specific ESR signals of irradiation-induced radical were detected in hut-gae berry and pollen extract product. As a results, it is considered that TL and ESR methods can be used to detect both hut-gae berry and pollen extract product. But cumin, caper, turmeric and boxthorn irradiated with gamma ray could be detected only by TL method. It is concluded that TL and ESR methods are suitable for detection of irradiated samples and a combined method is recommendable for enhancing the reliability of detection results.

Physicochemical properties and antioxidant activities of Streptococcus thermophilus KCCM 3782 strain fermented Cordyceps militaris grown on Tenebrio molitor (갈색거저리 동충하초의 Streptococcus thermophilus KCCM 3782 유산균 발효에 따른 물리화학적 특성과 산화방지 활성 비교)

  • Gim, Do-Woo;Park, Jun-Ki;Kim, Hyun-Jin;Cho, In-Kyung;Cho, Ja-Yong;Kim, Yong-Doo;Huh, Chang-Ki
    • Food Science and Preservation
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    • v.25 no.1
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    • pp.136-144
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    • 2018
  • This study aimed to provide basic evidence regarding the development of materials by analyzing the physicochemical properties and antioxidant activities of Streptococcus thermophilus KCCM 3782 strain-fermented Cordyceps militaris grown on Tenebrio molitor. Among the solvents tested, DPPH radical scavenging activity was the highest in the hot water-extracted sample after 30 min of extraction. Moisture content decreased, whereas crude protein and fat content increased, after lactic acid bacteria-mediated fermentation. Sodium, magnesium, calcium, and zinc contents increased, with potassium levels attaining the maximum value, whereas free amino acid content decreased after the fermentation. Among Hunter's color values, a value increased to $66.7{\rightarrow}149.92$ after fermentation, whereas the L and b values decreased to $15.79{\rightarrow}-15.75$ and $54.45{\rightarrow}0.01$, respectively. Cordycepin content assay increased from 7.02 mg% to 8.66 mg%. The DPPH free radical scavenging activity of the fermented product was 91.92 EDA%, which was higher than that of the extract (84.69 EDA%). The ABTS free radical scavenging and superoxide dismutase (SOD) activities were also higher in the fermented products.

Effect of Potassium Application Time on Rice Plant under The Limed Condition (석회(石灰)의 시용(施用)과 가리추비량(加里追肥量)에 관한 연구(硏究))

  • Oh, W.K.;Kim, T.S.;Han, K.W.;Park, C.H..;Kim, S.B.
    • Korean Journal of Soil Science and Fertilizer
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    • v.12 no.3
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    • pp.141-151
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    • 1979
  • To investigate the relationship between the effect of potassium basal and top dressing amount on rice plant under the limed condition, a pot experiment was conducted with Milyang 21, rice variety. Growing status, yield components and chemical component of rice, plant were determined and soils were analyzed along with the growing stages and obtained results are as follows. 1. Control treatment, without lime application shows a good vegetative growth as compared with lime treated one. However grain yield was higher in lime treated pot when potassium was applied as basal and top dressing. 2. There was no big difference between potassium applied and control treatment on growing status of nice plant until 20 days after transplanting. However in case of lime treated pot big difference were observed 20 days after transplanting resulting lower grain yield as compared with control treatment. This trend were severe in a lime treated treatment. 3. In control treatment, potassium basal dressing shows higher grain yield as increase the amount of basal dressing and the highest yield obtained in all basal potassium application treatment. However in case of lime treated pot when two-third of potassium were applied as basal dressing, potassium content of rice became lower at reproductive stage and resulted lower yield. When we applied all the potassium as a basal dressing, there were no differences as compared with control treatment in terms of grain yield. 4. The soil condition that affects potassium absorption disorder in rice plant such as unlimed condition, potassium application should be done as a basal dressing. However in limed condition that potassium absorption disorder occurs scarcely, and potassium content exists unsufficient amount in soil, large amount of potassium as basal dressing and the rest as top dressing are recommended. 5. The higher content of potassium in rice plant at the reproductive growing stage results heavier tillers as compared with lower one so that heavier tillers produce more grain yield. 6. At vigorous growing stage there was a positive correlation between electric conductivity of soil and amount of potasium absorbed by rice plant. This fact suggests that to obtain higher yield large amount of potassium top dressing at late of vegetative growing stage are necessary so that the content of potassium in rice plant will increase and results higher yield.

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Sasang Herb medicine, IRCT (InfraRed Computer Thermography), Yakchim (Korean herb-acupuncture) remedy (체통환자(體痛患者)의 사상의학적(四象醫學的) 사초(四焦)와 이목구비(耳目口鼻)를 중심(中心)으로 한 체열(體熱) 분석(分析))

  • Kim, Su-Beom;Song, Il-Byung
    • Journal of Sasang Constitutional Medicine
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    • v.8 no.1
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    • pp.377-393
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    • 1996
  • Lumbago is the common disease in the human, many people have been sicked the Lumbago. As the traditional methods of Lumbago treatment, acupuncture, moxibustion, herb medicines have been applied to a patient, nowadays, new methods have been applied physical remedy, Yakchim (Korean herb acupuncture) remedy, Chuna remedy to. This report was collected 73 Lumbago patients by name, sex, age, motive, symptoms, X-ray, CT, MRI, lRCT, Sasang constitution type, Sasang herb medicine, Yakchim, Chuna, period of remedy, satisfaction of remedy, at the "WooRee Korean Medical Clinic" during 21 months from Sep. 14, 1994 to May 25, 1996. And this report was studied about the distribution of the Sasang constitution type, the Sasang herb medicine, the effect, the period. The results were as follows: 1. Lumbago patients were distributed like that; Taeum-ln (太陰人) 47 (66.3 %), Soyang-In 16 (21.9 %), Soum-In (13.7 %), Taeyang-In (太陽人) 0. This was different from distribution of Donguisuseibowon (東醫壽世保元), Taeum-In (太陰人) 50%, Soyang-In (少陽人) 30 %, Soum-In (少陰人) 20 %, Taeyang-In (太陽人) little, this report shows that the number of Taeum-In (太陰人) is more than that of Donguisuseibowon and the number of Soum-In is less than that of Donguisuseibowon. 2. The average satisfaction of remedy was 60.3 %, Taeum-In's satisfaction was 66.0 %, Soum-In's satisfaction was 56.3 %, Soyang-In's satisfaction was 60.0 %. 3. The effective herb medicines were as follows, Soyang-In used the Hyong Bang Ji Hwang Tang (荊防地黃湯), Yuk Mi Ji Hwang Tang (六味地黃樓), Soum-In used the Sib Yi Mi Goan Jung Tang (十二味寬中湯), Taeum-In used the Chung Sim Yon Ja Tang (淸心蓮子陽), Chung Pae Sa Gan Tang (淸師爾肝湯), Yeol Da Han So Tang (熱多寒少湯). 4. The period of remedy was about 6 weeks. The period of remedy of each types was as follows, Taeum-In was about 5.7 weeks, Soum-In was about 6.8 weeks, Soyang-In was about 4.2 weeks. 5. The method of Lumbago remedy is divided three types, sprain Lumbago, Pyobyong (表病 : outside Syndromes) Libyong (裡病 : inside symdromes). Soum-In's methods are Pyobyong's ascending the Yang (陽), adding the Gi (氣) [升陽益氣], and Libyong's descending the inside Yim (裡陰) [裡陰降氣], Soyang-In's methods are Pyobyongs's decending the outside-Yim [表陰降氣], and Libyong's ascending the cool Yang (濟陽) [淸陽上升]. Taeum-In's methods are Pyobyong's ascending the Lung's Yang (肺陽升氣), and Libyong's colding the dried hot liver (淸肝燥熱). Taeyang's methods are strong the liver and making Yim. (補r肝生陰) 6. There are two methods for using the YakChim (Korean herb-acupuncture) by Sasang constitution medicine, one is to select the Yakchim, the other is to choice the point for appling the Yakchim. The first, to select the Yakchim, the other is follows; Soum-In can select the bee Venom, Soyang-In can select the H.O. (Hong Whoa 紅花), Taeum-In can select the I (Hodo 胡挑), V, O.K. (Ungdarn, 薦膽), Uwhang 牛黃, Sa-Hyang 麝香, etc., Palgang Yakchim (eight principles Korean herb-acupuncture (八剛藥鐵)) could made by abstracted Sasang herb medicine. The second, to choice the points for applying the Yakchim are used in the TaeGiuk Acupuncture method (太梗針法), Sacho (四焦, four warmer) by Sasang constritutional physiology and pathology.

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An Empirical Study in Relationship between Franchisor's Leadership Behavior Style and Commitment by Focusing Moderating Effect of Franchisee's Self-efficacy (가맹본부의 리더십 행동유형과 가맹사업자의 관계결속에 관한 실증적 연구 - 가맹사업자의 자기효능감의 조절효과를 중심으로 -)

  • Yang, Hoe-Chang;Lee, Young-Chul
    • Journal of Distribution Research
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    • v.15 no.1
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    • pp.49-71
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    • 2010
  • Franchise businesses in South Korea have contributed to economic growth and job creation, and its growth potential remains very high. However, despite such virtues, domestic franchise businesses face many problems such as the instability of franchisor's business structure and weak financial conditions. To solve these problems, the government enacted legislation and strengthened franchise related laws. However, the strengthening of laws regulating franchisors had many side effects that interrupted the development of the franchise business. For example, legal regulations regarding franchisors have had the effect of suppressing the franchisor's leadership activities (e.g. activities such as the ability to advocate the franchisor's policies and strategies to the franchisees, in order to facilitate change and innovation). One of the main goals of the franchise business is to build cooperation between the franchisor and the franchisee for their combined success. However, franchisees can refuse to follow the franchisor's strategies because of the current state of franchise-related law and government policy. The purpose of this study to explore the effects of franchisor's leadership style on franchisee's commitment in a franchise system. We classified leadership styles according to the path-goal theory (House & Mitchell, 1974), and it was hypothesized and tested that the four leadership styles proposed by the path-goal theory (i.e. directive, supportive, participative and achievement-oriented leadership) have different effects on franchisee's commitment. Another purpose of this study to explore the how the level of franchisee's self-efficacy influences both the franchisor's leadership style and franchisee's commitment in a franchise system. Results of the present study are expected to provide important theoretical and practical implications as to the role of franchisor's leadership style, as restricted by government regulations and the franchisee's self-efficacy, which could be needed to improve the quality of the long-term relationship between the franchisor and franchisee. Quoted by Northouse(2007), one problem regarding the investigation of leadership is that there are almost as many different definitions of leadership as there are people who have tried to define it. But despite the multitude of ways in which leadership has been conceptualized, the following components can be identified as central to the phenomenon: (a) leadership is a process, (b) leadership involves influence, (c) leadership occurs in a group context, and (d) leadership involves goal attainment. Based on these components, in this study leadership is defined as a process whereby franchisor's influences a group of franchisee' to achieve a common goal. Focusing on this definition, the path-goal theory is about how leaders motivate subordinates to accomplish designated goals. Drawing heavily from research on what motivates employees, path-goal theory first appeared in the leadership literature in the early 1970s in the works of Evans (1970), House (1971), House and Dessler (1974), and House and Mitchell (1974). The stated goal of this leadership theory is to enhance employee performance and employee satisfaction by focusing on employee motivation. In brief, path-goal theory is designed to explain how leaders can help subordinates along the path to their goals by selecting specific behaviors that are best suited to subordinates' needs and to the situation in which subordinates are working (Northouse, 2007). House & Mitchell(1974) predicted that although many different leadership behaviors could have been selected to be a part of path-goal theory, this approach has so far examined directive, supportive, participative, and achievement-oriented leadership behaviors. And they suggested that leaders may exhibit any or all of these four styles with various subordinates and in different situations. However, due to restrictive government regulations, franchisors are not in a position to change their leadership style to suit their circumstances. In addition, quoted by Northouse(2007), ssubordinate characteristics determine how a leader's behavior is interpreted by subordinates in a given work context. Many researchers have focused on subordinates' needs for affiliation, preferences for structure, desires for control, and self-perceived level of task ability. In this study, we have focused on the self-perceived level of task ability, namely, the franchisee's self-efficacy. According to Bandura (1977), self-efficacy is chiefly defined as the personal attitude of one's ability to accomplish concrete tasks. Therefore, it is not an indicator of one's actual abilities, but an opinion of the extent of how one can use that ability. Thus, the judgment of maintain franchisee's commitment depends on the situation (e.g., government regulation and policy and leadership style of franchisor) and how it affects one's ability to mobilize resources to deal with the task, so even if people possess the same ability, there may be differences in self-efficacy. Figure 1 illustrates the model investigated in this study. In this model, it was hypothesized that leadership styles would affect the franchisee's commitment, and self-efficacy would moderate the relationship between leadership style and franchisee's commitment. Theoretically, quoted by Northouse(2007), the path-goal approach suggests that leaders need to choose a leadership style that best fits the needs of subordinates and the work they are doing. According to House & Mitchell (1974), the theory predicts that a directive style of leadership is best in situations in which subordinates are dogmatic and authoritarian, the task demands are ambiguous, and the organizational rule and procedures are unclear. In these situations, franchisor's directive leadership complements the work by providing guidance and psychological structure for franchisees. For work that is structured, unsatisfying, or frustrating, path-goal theory suggests that leaders should use a supportive style. Franchisor's Supportive leadership offers a sense of human touch for franchisees engaged in mundane, mechanized activity. Franchisor's participative leadership is considered best when a task is ambiguous because participation gives greater clarity to how certain paths lead to certain goals; it helps subordinates learn what actions leads to what outcome. Furthermore, House & Mitchell(1974) predicts that achievement-oriented leadership is most effective in settings in which subordinates are required to perform ambiguous tasks. Marsh and O'Neill (1984) tested the idea that organizational members' anger and decline in performance is caused by deficiencies in their level of effort and found that self-efficacy promotes accomplishment, decreases stress and negative consequences like depression and emotional instability. Based on the extant empirical findings and theoretical reasoning, we posit positive and strong relationships between the franchisor's leadership styles and the franchisee's commitment. Furthermore, the level of franchisee's self-efficacy was thought to maintain their commitment. The questionnaires sent to participants consisted of the following measures; leadership style was assessed using a 20 item 7-point likert scale developed by Indvik (1985), self-efficacy was assessed using a 24 item 6-point likert scale developed by Bandura (1977), and commitment was assessed using a 6 item 5-point likert scale developed by Morgan & Hunt (1994). Questionnaires were distributed to Korean optical franchisees in Seoul. It took about 20 days to complete the data collection. A total number of 140 questionnaires were returned and complete data were available from 137 respondents. Results of multiple regression analyses testing the relationships between the each of the four styles of leadership shown by the franchisor as independent variables and franchisee's commitment as the dependent variable showed that the relationship between supportive leadership style and commitment ($\beta$=.13, p<.001),and the relationship between participative leadership style and commitment ($\beta$=.07, p<.001)were significant. However, when participants divided into high and low self-efficacy groups, results of multiple regression analyses showed that only the relationship between achievement-oriented leadership style and commitment ($\beta$=.14, p<.001) was significant in the high self-efficacy group. In the low self-efficacy group, the relationship between supportive leadership style and commitment ($\beta$=.17, p<.001),and the relationship between participative leadership style and commitment ($\beta$=.10, p<.001) were significant. The study focused on the franchisee's self-efficacy in order to explore the possibility that regulation, originally intended to protect the franchisee, may not be the most effective method to maintain the relationships in a franchise business. The key results of the data analysis regarding the moderating role of self-efficacy between leadership behavior style as proposed by path-goal and commitment theory were as follows. First, this study proposed that franchisor should apply the appropriate type of leadership behavior to strengthen the franchisees commitment because the results demonstrated that supportive and participative leadership styles by the franchisors have a positive influence on the franchisee's level of commitment. Second, it is desirable for franchisor to validate the franchisee's efforts, since the franchisee's characteristics such as self-efficacy had a substantial, positive effect on the franchisee's commitment as well as being a meaningful moderator between leadership and commitment. Third, the results as a whole imply that the government should provide institutional support, namely to put the franchisor in a position to clearly identify the characteristics of their franchisees and provide reasonable means to administer the franchisees to achieve the company's goal.

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Studies on the Mechanical Properties of Weathered Granitic Soil -On the Elements of Shear Strength and Hardness- (화강암질풍화토(花崗岩質風化土)의 역학적(力學的) 성질(性質)에 관(關)한 연구(硏究) -전단강도(剪斷强度)의 영향요소(影響要素)와 견밀도(堅密度)에 대(對)하여-)

  • Cho, Hi Doo
    • Journal of Korean Society of Forest Science
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    • v.66 no.1
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    • pp.16-36
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    • 1984
  • It is very important in forestry to study the shear strength of weathered granitic soil, because the soil covers 66% of our country, and because the majority of land slides have been occured in the soil. In general, the causes of land slide can be classified both the external and internal factors. The external factors are known as vegetations, geography and climate, but internal factors are known as engineering properties originated from parent rocks and weathering. Soil engineering properties are controlled by the skeleton structure, texture, consistency, cohesion, permeability, water content, mineral components, porosity and density etc. of soils. And the effects of these internal factors on sliding down summarize as resistance, shear strength, against silding of soil mass. Shear strength basically depends upon effective stress, kinds of soils, density (void ratio), water content, the structure and arrangement of soil particles, among the properties. But these elements of shear strength work not all alone, but together. The purpose of this thesis is to clarify the characteristics of shear strength and the related elements, such as water content ($w_o$), void ratio($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$), and the interrelationship among related elements in order to decide the dominant element chiefly influencing on shear strength in natural/undisturbed state of weathered granitic soil, in addition to the characteristics of soil hardness of weathered granitic soil and root distribution of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands. For the characteristics of shear strength of weathered granitic soil and the related elements of shear strength, three sites were selected from Kwangju district. The outlines of sampling sites in the district were: average specific gravity, 2.63 ~ 2.79; average natural water content, 24.3 ~ 28.3%; average dry density, $1.31{\sim}1.43g/cm^3$, average void ratio, 0.93 ~ 1.001 ; cohesion, $ 0.2{\sim}0.75kg/cm^2$ ; angle of internal friction, $29^{\circ}{\sim}45^{\circ}$ ; soil texture, SL. The shear strength of the soil in different sites was measured by a direct shear apparatus (type B; shear box size, $62.5{\times}20mm$; ${\sigma}$, $1.434kg/cm^2$; speed, 1/100mm/min.). For the related element analyses, water content was moderated through a series of drainage experiments with 4 levels of drainage period, specific gravity was measured by KS F 308, analysis of particle size distribution, by KS F 2302 and soil samples were dried at $110{\pm}5^{\circ}C$ for more than 12 hours in dry oven. Soil hardness represents physical properties, such as particle size distribution, porosity, bulk density and water content of soil, and test of the hardness by soil hardness tester is the simplest approach and totally indicative method to grasp the mechanical properties of soil. It is important to understand the mechanical properties of soil as well as the chemical in order to realize the fundamental phenomena in the growth and the distribution of tree roots. The writer intended to study the correlation between the soil hardness and the distribution of tree roots of Pinus rigida Mill. planted in 1966 and Pinus rigida ${\times}$ taeda in 199 to 1960 in the denuded forest lands with and after several erosion control works. The soil texture of the sites investigated was SL originated from weathered granitic soil. The former is situated at Py$\ddot{o}$ngchangri, Ky$\ddot{o}$m-my$\ddot{o}$n, Kogs$\ddot{o}$ng-gun, Ch$\ddot{o}$llanam-do (3.63 ha; slope, $17^{\circ}{\sim}41^{\circ}$ soil depth, thin or medium; humidity, dry or optimum; height, 5.66/3.73 ~ 7.63 m; D.B.H., 9.7/8.00 ~ 12.00 cm) and the Latter at changun-long Kwangju-shi (3.50 ha; slope, $12^{\circ}{\sim}23^{\circ}$; soil depth, thin; humidity, dry; height, 10.47/7.3 ~ 12.79 m; D.B.H., 16.94/14.3 ~ 19.4 cm).The sampling areas were 24quadrats ($10m{\times}10m$) in the former area and 12 in the latter expanding from summit to foot. Each sampling trees for hardness test and investigation of root distribution were selected by purposive selection and soil profiles of these trees were made at the downward distance of 50 cm from the trees, at each quadrat. Soil layers of the profile were separated by the distance of 10 cm from the surface (layer I, II, ... ...). Soil hardness was measured with Yamanaka soil hardness tester and indicated as indicated soil hardness at the different soil layers. The distribution of tree root number per unit area in different soil depth was investigated, and the relationship between the soil hardness and the number of tree roots was discussed. The results obtained from the experiments are summarized as follows. 1. Analyses of simple relationship between shear strength and elements of shear strength, water content ($w_o$), void ratio ($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$). 1) Negative correlation coefficients were recognized between shear strength and water content. and shear strength and void ratio. 2) Positive correlation coefficients were recognized between shear strength and dry density. 3) The correlation coefficients between shear strength and specific gravity were not significant. 2. Analyses of partial and multiple correlation coefficients between shear strength and the related elements: 1) From the analyses of the partial correlation coefficients among water content ($x_1$), void ratio ($x_2$), and dry density ($x_3$), the direct effect of the water content on shear strength was the highest, and effect on shear strength was in order of void ratio and dry density. Similar trend was recognized from the results of multiple correlation coefficient analyses. 2) Multiple linear regression equations derived from two independent variables, water content ($x_1$ and dry density ($x_2$) were found to be ineffective in estimating shear strength ($\hat{Y}$). However, the simple linear regression equations with an independent variable, water content (x) were highly efficient to estimate shear strength ($\hat{Y}$) with relatively high fitness. 3. A relationship between soil hardness and the distribution of root number: 1) The soil hardness increased proportionally to the soil depth. Negative correlation coefficients were recognized between indicated soil hardness and the number of tree roots in both plantations. 2) The majority of tree roots of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands distributed at 20 cm deep from the surface. 3) Simple linear regression equations were derived from indicated hardness (x) and the number of tree roots (Y) to estimate root numbers in both plantations.

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