• Title/Summary/Keyword: Needles

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Characteristics of PCDD/Fs Deposited on Pine Needles and Soil (소나무잎과 토양에 침착된 PCDD/Fs 특성)

  • Chun, Man-Young;Yeo, Hyun-Gu
    • Korean Journal of Environmental Agriculture
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    • v.24 no.3
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    • pp.280-288
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    • 2005
  • The aim of this study was to investigate deposition characteristics of atmospheric PCDD/Fs on pine needles and soil. Concentration of PCDD/Fs on soil were higher than those in pine needles, being 7.4 times for ${\Sigma}PCDDs$, 2.3 times for ${\Sigma}PCDFs$, and 5.4 times for ${\Sigma}PCDD/Fs$ respectively. The ratios of the concentration of each homologue in soil to that in pine needles increased as the number of chlorine atoms increased. The concentration (%) of each congener to ${\Sigma}PCDD/Fs$ was higher in the one with a small number of chlorine atoms substituted, such as tetra- to hexa-homologues in pine needle samples and in one with a large number of chlorine atoms, such as hepta- to octa-homologues in soil samples. Lower-chlorinated homologues of PCDD/Fs were mainly accumulative deposited in pine needles, whereas higher-chlorinated ones were on soil.

Depositional Characteristics of Atmospheric PBDEs on Pine Needles, Bark and Soil (대기 중 폴리브롬화디페닐에테르의 소나무 잎, 소나무 껍질 및 토양으로의 침착 특성)

  • Chun, Man Young
    • Journal of Environmental Health Sciences
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    • v.40 no.3
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    • pp.215-224
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    • 2014
  • Objective: This study was carried out in order to determine the depositional characteristics of pine needles, pine bark, and soil used as a passive air sampler (PAS) for atmospheric polybrominated diphenyl ethers (PBDEs). Methods: All three media were sampled from the same site. The PBDE concentrations were analyzed by HRGC/HRMS, and the lipid contents were measured using the gravimetric method by n-hexane extraction. Results: The total PBDE concentration was the highest in soil (22,274.57 pg/g dry), followed by pine bark (20,266.39 pg/g dry), and then pine needles (7,380.22 pg/g dry). Pine needles contained the highest lipid contents (21.31 mg/g dry), whereas soil (10.01 mg/g dry), and pine bark (4.85 mg/g dry) contained less. There were poor correlations between lipid content and total PBDE concentrations in the media ($R^2$=0.8216, p=0.2814). Congeners BDE 47, 99, 183, 196, 197, 206, 207 and 209 showed peak concentrations. Among these, BDE 206, 207, and 209 are highly brominated PBDEs that exist as particulates in ambient air. They accounted for 81.2% [69.2 (pine needles) - 89.0% (tree bark)] of the concentration and therefore are noted as the main congener of the total PBDEs. Conclusions: It can therefore be concluded that for reducing error by improper sampling, the same species of media should be recommended for use as a PAS for atmospheric PBDEs due to the differences in depositional characteristics.

Variation in Photosynthesis and Leaf Pigments of Susceptible Pinus densiflora and Resistant Pinus rigida Following Pine Gall Midge Attack (솔잎혹파리 침해(侵害)에 따른 감수성수종(感受性樹種)인 소나무와 저항성수종(抵抗性樹種)인 리기다소나무에 있어서 광합성(光合成) 및 엽(葉)의 색소변이(色素變異)에 관한 연구(硏究))

  • Lee, Don Koo;Sung, Joo Han
    • Journal of Korean Society of Forest Science
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    • v.65 no.1
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    • pp.1-11
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    • 1984
  • Susceptible trees of Pinus densiflora and resistant trees of Pinus rigida following pine gall midge (Tnecodiplosis japonensis Uchida et Inouye) attack were seasonally compared to examine the variation in needle growth and photosynthetic ability, respiration rate, chlorophyll contents, carotenoid and anthocyanin contents. Also, carotenoid and anthocyanin contents of larvae both from soil and from galled tissue were compared during March and September, respectively. The plantation damaged severely by this insect consisted mostly of 10-to 15-year old P. rigida and P. densiflora. The results obtained in this study were as follows: 1) The length of the infested needles of P. densiflora decreased by 48.1 percent compared with the normal needles, while that of P. rigida did 37.4 percent. 2) All of P. densiflora and P. rigida showed higher photosynthetic ability in normal needles than in infested needles. The maximum photosynthetic ability of P. densiflora was shown in mid-August, while that of P. rigida in mid-October. In contrast to that, respiration rate of infested needles was higher than that of normal needles in both species. The respiration rate of P. rigida was higher than that of P. densiflora. 3) P. rigida had higher total chlorophyll contents than P. densiflora. The total carotenoid contents tents in infested needles were higher than those in normal needles of both species. 4) Total carotenoid contents were generally higher in P. rigida than in P. densiflora during the growing season. The total carotenoid content (0.094mg/g) in larvae from soil was similar to that (0.092mg/g) in larvae from galled tissues. 5) Infested needles of both species showed higher anthocyanin contents than normal needles. Higher anthocyanin contents in galled needles were due primarily to its active formation stimulated by larval attack. Thus, reddish-brown coloration occurred only in galled needles of P. densiflora.

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Cation Deficiencies in Needles and Fine Roots of Pitch Pine in Seoul Metropolitan Area (首都圈地域에서 리기다소나무 잎과 잔뿌리 속의 陽이온 부족)

  • Rhyu, Tae-Cheol;Kim, Kee-Dae;Kim, Joon-Ho
    • The Korean Journal of Ecology
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    • v.17 no.3
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    • pp.277-286
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    • 1994
  • The contents of major elements were determined in current-year and previous-year needles and fine roots of pitch pine (Pinus yzgida) at 33 sites in Seoul and its vicinity. Contrary to Ca and Al in needles, N, P, Mg and K contents in current-year needles were higher than those in previous-year needles. The N, P, K and Al contents in current-year needles in Seoul were not significantly different from those in rural areas. In contrast, Ca and Mg contents in needles in Seoul were significantly lower than those in suburbs and rural areas. The N /Ca and N /Mg ratios in needles in urban Seoul were higher than those in rural areas. Mg contents in fine roots in soil of 0-5 cm depth increased along with distance from the center of Seoul, while Al contents in fine root in soil of 5-10 cm depth decreased along with distance from the center of Seoul. Al contents in fine roots in soil layer in Seoul and suburbs were higher than those in rural areas. Al contents in fine roots in litter layer were 1 /3 - 1 /2 times lower than those in soil layer for all areas. A1 content in fine roots in deep soil was higher than that in top soil. Therefore growth decline of pitch pine in Seoul and suburbs was thought to be caused by Ca and Mg deficiency in plant tissues and Al toxicity to fine roots. Abnormal vertical distribution of fine roots of pitch pine in Seoul and its vicinity were interpreted as the result of growth reduction of fine roots by Al toxicity in deep layer of acid soil.

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Effects of Addition of Pine Needle Extracts in Different Forms on the Antioxidant and Residual Nitrite Contents of Emulsified Sausages during Cold Storage (제조 방법이 다른 솔잎 추출물 첨가가 유화형 소시지의 냉장 저장 중 항산화 및 아질산염 잔존량에 미치는 영향)

  • Kim, Young-Jik
    • Food Science of Animal Resources
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    • v.31 no.1
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    • pp.74-80
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    • 2011
  • The objective of this study was to determine the shelf-life effects and residual nitrite content of emulsified sausages added with pine needles during cold storage. The sausage consisted of four types: no pine needles added (control), pine needle juice added (T1), ethanol extract of pine needles added (T2), and boiling extract of pine needles added (T3). Each sausage type was tested in triplicate and assigned to one of four storage periods: 0, 10, 20, or 30 d. As storage time increased, the presence of pine needles resulted in decreased pH, meat color (CIE $L^*$, $a^*$ and $b^*$), residual nitrite value, and increased thiobarbituric acid reactive substances (TBARS) values and total plate counts (TPC). Values for pH, TBARS, residual nitrite, total plate counts and CIE $L^*$ and $a^*$ decreased significantly with added pine needles relative to the control (p<0.05). In particular, T2 was significantly (p<0.05) more effective for delaying lipid oxidation than the other treatment groups. In conclusion, the results demonstrate that adding an ethanol extract of pine needles (T2) to emulsified sausages tended to improve antioxidative and antimicrobial effects and reduce residual nitrite content during storage compared to the other treatment groups.

A Study on How to Lower the Grounding Impedance by Needles-typed Grounding Rods (접지침봉에 의한 접지임피던스를 낮추는 방안 연구)

  • Park, Sung-Yeol
    • Journal of the Society of Disaster Information
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    • v.18 no.1
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    • pp.19-28
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    • 2022
  • Purpose: One of the methods for preventing disasters such as fire, explosion, and electric shock caused by electricity is to perform grounding. In case of the grounding current includes a frequency component having a high, it is preferable to measure grounding impedance rather than grounding resistance. This study proposes countermeasures to reduce grounding impedance to suppress an ground potential rise due to a grounding current having a frequency component of several kHz or more. Method: General grounding rods and needles-typed grounding rods were buried in the ground, and grounding resistance and grounding impedance were measured, respectively. The characteristics of grounding impedance according to frequency were identified. Result: There was little difference in the measurement results of the grounding resistance between general grounding rods and needles-typed grounding rods. In a frequency range lower than 62.5kHz, there was little difference in the measurement results of the grounding resistance between general grounding rods and needles-typed grounding rods. In a frequency range higher than 62.5kHz, the grounding impedance of needles-typed grounding rods was reduced by about 15% than the grounding impedance of general grounding rods. Conclusion: In the commercial frequency domain, it is effective to connect several grounding rods (common grounding) to lower the grounding resistance value. In the frequency domain of several kHz or more, it is expected that needles-typed grounding rods can effectively reduce the ground potential rise due to the grounding current.

A Study on the Characteristics of an Arc-Inducing Driven Rod with Needles (아크유도형 침부 접지봉의 특성 연구)

  • 박중신;정종욱;곽희로
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.14 no.1
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    • pp.118-123
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    • 2000
  • This paper describes the characteristics of a newly suggested arc-inducing driven rod with needles which could effectively spread out both the failure current with power frequency and the lightning current. The structural characteristic of the driven rod was that needles were attached on the surface of the conventional shaped driven rod and the driven rod with needles was installed inside of a copper pipe.As a result of analyzing the characteristics of this suggested driven rod when it was employed as the driven rod of an arrester in distribution system, it was verified that the primary voltage of the arrester was reduced by effectively exhausting the electrical energy since the arc occurred between the needle and the copper pipe.

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Estimation of Atmospheric PAH Concentrations and Sources at Several Sites Using Pine Needles as a Passive Air Sampler (소나무잎을 Passive Air Sampler로 이용하여 지역별 대기 중 다환방향족 탄화수소의 농도 및 발생원 추정)

  • Chun, Man-Young
    • Journal of Environmental Health Sciences
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    • v.40 no.1
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    • pp.38-46
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    • 2014
  • Objectives: This study was carried out in order to estimate atmospheric polycyclic aromatic hydrocarbon (PAH) concentrations and sources using pine needles as a passive air sampler (PAS) in urban (Pyeongtaek), semirural (Anseong) and rural (Jincheon) sites. Methods: One-year-old pine needles were collected for analysis of their PAH concentrations ($C_{p,n}g/g$ dry) at the end of December. PAHs concentrations in the ambient air ($C_a$, $ng/m^3$) were calculated with a $Log(C_p/C_a)-LogK_{oa}$ correlational equation. Results: PAHs concentrations in ambient air ($C_a$) were high, in the order of urban ($114.03ng/m^3$), semirural ($105.17ng/m^3$) and rural ($61.91ng/m^3$) sites. However, distributions of PAH isomer concentrations were very similar. PAHs of which molecular weight is smaller than 228.30 (AcPy, Acp, Flu, Phen, Ant, Flt, Pyr, BaA, Chry) made up most of the PAHs in the ambient air (96.6-98.5%). Conclusion: At urban, semirural and rural sites, it was concluded that the main source of PAHs in the ambient air ratio of each PAH isomer concentration was cars, especially diesel vehicles.

The Effect of Antioxygenic substances in Pine Needles on the Photooxidation of Linoleic Acid (송옆중의 항산화성 물질이 리놀산의 광산화에 미치는 영향)

  • Paik, Taik-Hong;Lee, Meen-Soo;Yi, Jun-Heung
    • Journal of the Korean Applied Science and Technology
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    • v.4 no.2
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    • pp.25-30
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    • 1987
  • In order to investigate the effect to antioxygenic substances in Pine Needles on the photooxidation of linoleic acid (linoleic acid 100mg/10ml ethanol) added antioxidants and antioxygenic substances in Pine Needles was irradiated by the tungsten lamp attached with red fitter. The Photo oxidation of linoleic acid (LA) was conformed with Lea method and rhodan method. The following results were obtained: 1. Photooxidation of LA was greatly increased the presence of photosensitizer. However the Photo oxidation of LA without photosensitizer was smoothly increased by the irradiation. 2. The Photo oxidation of LA without irradiation occured quite lately whether photosensitizer was present or absent. 3. Photooxidation of LA under the presence of photosensitizer was inhibited by the addition of $dl-{\alpha}-tocopherol$ and the acetone fraction of methanol extract of Pine Needles but inhibited by BHT. Photooxidation of LA increased gradually as the addition of BHT increased but decreased gradually as that of acetone fraction increased.