• Title/Summary/Keyword: 과학 실험

Search Result 13,321, Processing Time 0.04 seconds

The water absorption of wood by water-soaking time (수침시간(水浸時間)에 의(依)한 목재(木材)의 흡수성(吸收性))

  • Lee, Won Yong
    • Journal of Korean Society of Forest Science
    • /
    • v.7 no.1
    • /
    • pp.3-7
    • /
    • 1968
  • The Capacity of wood to absorb water is very important as the basis data for wood industry, particularly in preservatives impregnation, manufacturing of improved wood, selection of packing boards, etc. In this study differences in Water absorbing Capacity of wood by structual section, water soaking time were investigated. (1) The species used in this investigation were Larix olgensis Henry Var. Koreana Nakai and Juglans mandshurica Max., and dimension of these testing wood block was $30{\times}30{\times}100cm$; and these were soaked in fresh water of $25{\pm}1^{\circ}C$ for 8.5day and 0.5 day, before measurement. (2) The result showed that the water absorption by cross sections was greater than by either radial or tangential section and there were no differences between radial and tangential section. (3) The water absorption of Juglans mandshurica Max. which has the relatively low specific gravity was greater than Larix olgensis Henry Var. Koreana Nakai which has generally high specific gravity. (4) The result showed an increase in the absorbed water with increase in the length of soaking time. However the water absorption rate during the early period of soaking was very high and thereafter the rate decreased with passage of time. More than a half of the total water absorption was achieved during the first 2 days approximately. (5) The relationships between the length of the soaking-time and water absorption were found to be as follows : Larix olgensis Henry Var. Koreana Nakai Cross section : $y=111.1{\times}^{0.6516}$ radial section : $y=32.2{\times}^{0.5146}$ tangential section : $y=36.5{\times}^{0.5112}$ Juglans mandshurica Max. Cross section : $y=216.1{\times}^{0.5914}$ radial section : $y=27.9{\times}^{0.5832}$ tangential section : $y=50.9{\times}^{0.4769}$ Where : y is amount of water absorption ($mg/cm^2$) x is water-soaking time (days).

  • PDF

Anatomical Studies on the Features of Rays in Compression Wood of Korean Red Pine(Pinus densiflora S. et Z.) (소나무(Pinus densiflora S. et Z.) 압축이상재(壓縮異常材)의 방사조직(放射組織) 특성(特性)에 관한 해부학적(解剖學的) 연구(硏究))

  • Chung, Youn Jib;Lee, Phil Woo
    • Journal of Korean Society of Forest Science
    • /
    • v.78 no.2
    • /
    • pp.119-131
    • /
    • 1989
  • This experiment was executed to investigate and compare qualitative and quantitative anatomical features in compression wood, opposite wood, and side wood formed in a bent stem, a straight branch, and an exposed horizontal root of Korean red pine(Pinus densiflora S. et Z.). The respective four discs containing compression wood taken at 20cm interval both in stem and branch as well as a disc containing well developed compression wood from horizontal root were analyzed. Percentage of compression wood and eccentricity showed decreasing tendency with the increasing distance in height direction of stem and length direction of branch. The qualitative anatomical features of compression wood appeared to differ from those of side and opposite wood in very gradual tracheid transition from earlywood to latewood, roundish tracheid shape on cross surface, tracheid distortion at tip on radial surface, existence of intercellular space, and helical cavity in tracheid wall. And the differences in these qualitative features among the compression wood, opposite wood, and side wood became less intensive with the decreasing trends in percentage of compression wood and eccentricity. The quantitative anatomical features in compression wood also appeared to be wider in that respective widths of fusiform and uniseriate ray than those of opposite and side wood, but the heights of fusiform and uniseriate ray in compression wood were smaller than in opposite and side wood. The number of horizontal resin canal(fusiform ray) and uniseriate ray, however, showed no differences among the compression wood, opposite wood, and side wood. And the number of vertical resin canal in unit area, $4{\pi}mm^2$ of compression wood was fewer than that in opposite wood, whereas numerous vertical resin canals contained in a growth ring. These rays of compression wood seemed to be characterized by smaller height and wider width than those of opposite and side wood.

  • PDF

Protective Effects of a Herbal Composition (HemoHIM) Against Apoptosis Induced by Oxidative Stress of Hydrogen Peroxide (과산화수소의 산화적 스트레스로 유도된 Apoptosis에 대한 생약복합조성물(HemoHIM)의 방호효과 평가)

  • Shin, Sung-Hae;Kim, Do-Soon;Kim, Mi-Jung;Kim, Sung-Ho;Jo, Sung-Kee;Byun, Mung-Woo;Yee, Sung-Tae
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.35 no.9
    • /
    • pp.1127-1132
    • /
    • 2006
  • In our previous study, a novel herb mixture (HIM-I) of Angelica gigas radix, Cnidium officinale rhizoma, and Paeonia japonica radix was developed to protect the intestinal and immune systems and promote its recovery against radiation damage. A new herbal composition (HemoHIM) with the high immune modulating activity was developed from HIM-I. HIM-I was fractionated into ethanol fraction (HIM-I-E) and polysaccharide fraction (HIM-I-P). And HemoHIM was prepared by adding HIM-I-P to HIM-I. HemoHIM showed more effective than HIM-I in immune modulation as well as radioprotection. The present study is designed to investigate the protective effects of HIM-I, HIM-I-P, and HemoHIM on hydrogen peroxide $(H_2O_2)$ induced apoptosis of human promyelocytic leukemia (HL-60) cells. It was shown that $H_2O_2$ treatment reduced the viability of cells, and increased appearance of DNA ladders, hypodiploid (subG1) cells, and phosphatidylserine translocation level. Pretreatment of HemoHIM significantly reduced the cytotoxic effect induced by $H_2O_2$, associated with reducing the translocation of phosphatidylserine, hypodiploid cells and DNA ladders. HemoHIM appeared to be more protective than HIM-I against $H_2O_2$ induced apoptosis whereas, it exhibited similar activity to HIM-I-P. These results indicated that HemoHIM might be an useful agent for protection against oxidative stress $(H_2O_2)-induced$ apoptosis as well as immune modulation, especially since it is a relatively nontoxic natural product.

Comparison of antioxidant capacity of protein hydrolysates from 4 different edible insects (식용곤충별 단백가수분해물의 항산화 활성 비교)

  • Jang, Hyun-Young;Park, Chae-Eun;Lee, Syng-Ook
    • Korean Journal of Food Science and Technology
    • /
    • v.51 no.5
    • /
    • pp.480-485
    • /
    • 2019
  • The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.

Preliminary Research on the Effect of Cosmetic Containing Ginseng Extract on Quality of Life of Healthy Women Based on Skindex-16 (인삼 추출물 함유 한방화장품이 건강한 성인 여성의 삶의 질에 미치는 영향에 관한 예비 연구; Skindex-16을 중심으로)

  • Cho, Ga Young;Park, Hyo Min;Kwon, Lee Kyung;Cho, Sung A;Kang, Byung Young;Kim, Yoon Bum
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.41 no.4
    • /
    • pp.333-340
    • /
    • 2015
  • This study is designed to analyze the effect of skincare using cosmetic containing ginseng extract, on improving quality of life (QOL) of healthy women, with blind testing. QOL is a concept that represents how one's disease or health condition can physically, psychologically, and socially influence his or her daily life. The study was conducted to assess the effect of a ginseng cosmetic preparation on quality of life (QOL) using the Skindex-16 score, stratified by blind versus non-blinded option. 45 healthy women aged between 30 and 49 years with no skin disease were recruited for this study. Volunteers were divided into two groups. Group A (n = 22) received anti-aging cream with ginseng extract in the original packaging, which included the brand name and logo. Group B (n = 23) received the same cream in a plain white jar without any package decoration or logo. Both groups used the cream for 8 weeks. For the skin-related QOL assessment, Skindex-16 was used at baseline, forth, and eighth week. All volunteers except two dropouts in Group A completed the dermatology-specific QOL measure, Skindex-16, at baseline, after 4 weeks, and after 8 weeks of treatment with the provided samples. As a result, the mean score of 43 participants at baseline was $22.70{\pm}4.82$. There was a significant difference between the baseline score and the score after 8 weeks in both groups: The scores changed from $23.30{\pm}5.14$ to $20.20{\pm}4.83$ in Group A, from $22.17{\pm}4.58$ to $20.52{\pm}3.60$ in Group B. The "Symptom" subscale of Skindex-16 improved after 4 weeks and the "Emotion" subscale improved after 8 weeks in Group A. The "Function" subscale did not show improvement in either groups. Both groups showed no interaction effect between follow up time and groups in Skindex-16 and subscale. This research opens up the possibility of skincare using ginseng cream having a positive effect on QOL in healthy women. Moreover, one can predict that skincare ritual itself may have greater impact on the improvement of QOL, compared to the product packaging.

Air Gasification Characteristics of Unused Woody Biomass in a Lab-scale Bubbling Fluidized Bed Gasifier (미이용 산림바이오매스 및 폐목재의 기포 유동층 Air 가스화 특성 연구)

  • Han, Si Woo;Seo, Myung Won;Park, Sung Jin;Son, Seong Hye;Yoon, Sang Jun;Ra, Ho Won;Mun, Tae-Young;Moon, Ji Hong;Yoon, Sung Min;Kim, Jae Ho;Lee, Uen Do;Jeong, Su Hwa;Yang, Chang Won;Rhee, Young Woo
    • Korean Chemical Engineering Research
    • /
    • v.57 no.6
    • /
    • pp.874-882
    • /
    • 2019
  • In this study, the gasification characteristics of four types of unused woody biomass and one waste wood in a lab-scale bubbling fluidized bed gasifier (Diameter: 0.11 m, Height: 0.42 m) were investigated. Effect of equivalence ratio (ER) of 0.15-0.3 and gas velocity of $2.5-5U_0/U_{mf}$ are determined at the constant temperature of $800^{\circ}C$ and fuel feeding rate of 1 kg/h. The silica sand particle having an average particle size of $287{\mu}m$ and olivine with an average particle size of $500{\mu}m$ were used as the bed material, respectively. The average product gas composition of samples is as follows; $H_2$ 3-4 vol.%, CO 15-16 vol.%, $CH_4$ 4 vol.% and $CO_2$ 18-19 vol.% with a lower heating value (LHV) of $1193-1301kcal/Nm^3$ and higher heating value (HHV) of $1262-1377kcal/Nm^3$. In addition, it was found that olivine reduced most of C2 components and increased $H_2$ content compared to silica sand, resulting in cracking reaction of tar. The non-condensable tar decreases by 72% ($1.24{\rightarrow}0.35g/Nm^3$) and the condensable tar decreases by 27% ($4.4{\rightarrow}3.2g/Nm^3$).

Apoptosis Induction by Dendropanax morbiferus Leaves Extract in Human Breast Cancer Cells SK-BR-3 through MAPK Pathway (유방암 세포에서 황칠나무 잎 추출물의 MAPK 경로를 통한 apoptosis 유도)

  • Jung, Gi Hwan;Kim, Sung Hyun;Woo, Joong Seok;Yoo, Eun Seon;Lee, Jae Han;Han, So Hee;Jung, Soo Hyun;Kim, Sae Man;Kim, Eun Gee;Shin, Man Jae;Cho, Ho Min;Jung, Ji Youn
    • Journal of Life Science
    • /
    • v.31 no.9
    • /
    • pp.827-833
    • /
    • 2021
  • Dendropanax morbiferus leaves (DPL) has been used as a medicine since ancient times in various diseases such as inflammation, diabetes, and cancer. In particular, it has been found to have anticancer effects on several types of cancer cells, but the anticancer effect on breast cancer cells SK-BR-3 has not yet been revealed. Therefore, in this study, DPL caused proliferation inhibition in breast cancer cells SK-BR-3 and the anticancer effect by inducing apoptosis was confirmed, through an in vitro experiment. In order to examine the effect of DPL on cell viability, MTT assay was performed to confirm a significant decrease in the concentration of cell viability. DAPI staining was performed to examine the effect of DPL on cellular morphological changes and increase of apoptotic bodies. To supplement this, an increase in the apoptosis rate was also confirmed through flow cytometry after staining with annexin V/PI. Western blot was performed to confirm apoptosis-related proteins. DPL increased the expression of Cleaved-PARP, Bax whereas decreased the expression of Bcl-2. Changes in the expression levels of MAPK pathway proteins p-ERK1/2, p-JNK, and p-p38 were also confirmed, and a significant increase in p-p38 was observed. These results indicated that DPL induced apoptosis, through p-p38 MAPK signal pathway in SK-BR-3 breast cancer cells.

Improving Growth and Yield in Cherry Tomato by Using Rootstocks (대목 종류에 따른 방울토마토 생장과 수량 증가)

  • Lee, Hyewon;Lee, Jun Gu;Hong, Kue Hyon;Kwon, Deok Ho;Cho, Myeong Cheoul;Hwang, Indeok;Ahn, Yul Kyun
    • Journal of Bio-Environment Control
    • /
    • v.30 no.3
    • /
    • pp.196-205
    • /
    • 2021
  • This research was conducted in order to analyze the difference in yield through the changes in growth and measuring the photosynthesis efficiency in cherry tomatoes. Seedlings of cherry tomato 'Nonari' were used as scion and non-grafted control, while 4 different grafted tomatoes 'Powerguard', 'T1', 'L1', and 'B.blocking' were used as rootstocks. Plants grafted onto 'B.blocking' produced the highest fruit yield (417.5 g plant-1), whereas non-grafted plant 'Nonari' had the lowest fruit yield, (354.2 g plant-1) at the latter period of cherry tomatoes in May. The flowering position in May, plant grafted onto 'B.blocking', showed 14-17 cm, whereas non-grafted plant 'Nonari' showed 10-14 cm. The growth strength on May 15, non-grafted plant 'Nonari', showed 8.43 mm which was the lowest value among the treatments. Grafted plants kept the growth balance until the end of the harvest that led to an increase in fruit yield, while non-grafted plant weakened the vigor earlier that led to a decrease in fruit yield. Grafted plants showed higher values of chlorophyll fluorescence variables than the values of non-grafted plant. These results indicate that grafting influenced fruit yield which was observed as maintaining growth balance for longer and an increase in photosynthesis efficiency compared to non-grafting.

Whitening Activity of Sambucus Sieboldiana Var. Pendula (Nakai) Extract (말오줌나무 추출물의 미백활성 검증)

  • Yoo, Dan-Hee;Kim, Jin-Tae;Oh, Min-Jeong;Yeom, Hyeon-Ji;Lee, Jin-Young
    • Journal of Life Science
    • /
    • v.29 no.3
    • /
    • pp.279-286
    • /
    • 2019
  • This study evaluated the anti-oxidant and whitening effects of a 70% ethanol extract of the Sambucus sieboldiana var. pendula (Nakai) (SS). At $1,000{\mu}g/ml$ concentration, the electron donating ability of this SS extract was found to be 86.21% and the ABTS+ radical scavenging ability was 97.9%. In terms of whitening activity, the tyrosinase inhibitory effect of the extract was 37%, also at $1,000{\mu}g/ml$ concentration. To explore the extractefftoxicity to B16F10 melanoma cells, a 3-[4,5-dimethyl-thiazol-2-yl]-2,5-diphenyl-tetrazoliumbromide assay was performed. Results showed 90% or more cells remained viable at $100{\mu}g/ml$ concentration. A Western blot of the SS extract was used to measure microphthalmia-associated transcription factor (MITF), tyrosinase-related protein-1 (TRP-1), tyrosinase relate protein-2 (TRP-2), and the tyrosinase protein expression inhibitory effect at 25, 50, $100{\mu}g/ml$ concentrations; ${\beta}-actin$ was used as a positive control. Consequently, the MITF, TRP-1, TRP-2, and the tyrosinase protein expression inhibitory effect were seen to decrease by 34.5%, 45.6%, 58.4%, and 79.6%, respectively, at $100{\mu}g/ml$ concentration. These were also then measured by reverse transcription-polymerase chain reaction at 25, 50, $100{\mu}g/ml$ concentrations with GAPDH as a positive control. As a result, the SS extract was seen to decrease MITF, TRP-1, TRP-2, and the tyrosinase protein expression inhibitory effect by 85.4%, 67.5%, 85.2%, 67.1%, respectively at the $100{\mu}g/ml$ concentration. We therefore confirmed the possibility of Sambucus sieboldiana var. pendula (Nakai) extract as a whitening material.

Study on the Casting Technology and Restoration of "Sangpyong Tongbo" (상평통보 주조와 복원기술연구)

  • Yun, Yong-hyun;Cho, Nam-chul;Jeong, Yeong-sang;Lim, In-ho
    • Korean Journal of Heritage: History & Science
    • /
    • v.47 no.4
    • /
    • pp.224-243
    • /
    • 2014
  • This study examined the materials and casting technology(cast, alloy, etc.) used in the manufacturing of bronze artifacts based on old literature such as Yongjae Chonghwa, Cheongong Geamul, and The Korea Review. In the casting experiment for restoration of Sangpyong Tongbo, a bronze and brass mother coin mold was made using the sand mold casting method described in The Korea Review. The cast was comprised of the original mold plate frame, wooden frame, and molding sand. Depending on the material of the outer frame, which contains the molding sand, the original mold plate frame can be either a wooden frame or steel frame. For the molding sand, light yellow-colored sand of the Jeonbuk Iri region was used. Next, the composition of the mother alloy used in the restoration of Sangpyong Tongbo was studied. In consideration of the evaporation of tin and lead during actual restoration, the composition of Cu 60%, Zn 30%, and Pb 10% for brass as stated in The Korea Review was modified to Cu 60%, Zn 35%, and Pb 15%. For bronze, based on the composition of Cu 80%, Sn 6%, and Pb 14% used for Haedong Tongbo, the composition was set as Cu 80%, Sn 11%, and Pb 19%. The mother coin mold was restored by first creating a wooden father coin, making a cast from the wooden frame and basic steel frame, alloying, casting, and making a mother coin. Component analysis was conducted on the mother alloy of the restored Sangpyong Tongbo, and its primary and secondary casts. The bronze mother alloy saw a 5% increase in copper and 4% reduction in lead. The brass parent alloy had a 5% increase in copper, but a 4% and 12% decrease in lead and tin respectively. Analysis of the primary and secondary mother coin molds using an energy dispersive spectrometer showed that the bronze mother coin mold had a reduced amount of lead, while the brass mother coin mold had less tin. This can be explained by the evaporation of lead and tin in the melting of the primary mother coin mold. In addition, the ${\alpha}$-phase and lead particles were found in the mother alloy of bronze and brass, as well as the microstructure of the primary and secondary coin molds. Impurities such as Al and Si were observed only in the brass mother coin mold.