• 제목/요약/키워드: P2P Sites

검색결과 2,038건 처리시간 0.026초

전나무림, 잣나무림 유역에서 수관통과우와 수간유하수의 수소이온농도 및 전기전도도에 미치는 산림시업의 영향 (Influences of Forest Management Practices on pH and Electrical Conductivity in the Throughfall and Stemflow with the Abies holophylla and Pinus koraiensis Dominant Watershed)

  • 정용호;김경하;박재현
    • 생태와환경
    • /
    • 제35권1호통권97호
    • /
    • pp.52-61
    • /
    • 2002
  • 이 연구는 전나무림과 잣나무림에서 산림시업에 따른 산림의 수질정화기능을 평가하기 위한 기초자료를 제공하기 위하여 광릉시험림 31, 33임반내 산림시업지 전나무림, 잣나무림 유역에서 1999년 5월부터 1999년 11월까지 7개의 단위강우를 대상으로 강우, 임내우를 강우직 후 초기와 그 이후 총량의 pH및 전기전도도 등을 분석한 결과는 다음과 같다. 1)초기수관통과우의 평균 pH는 전나무림 시업구>잣나무림 시업구>잣나무림 비시업구>전나무림 비시업구의 순이었으며, 총수관통과우의 평균 pH는 전나무림 시업구>잣나무림 시업구>전나무림 비시업구>잣나무림비시업구의 순으로 전나무림, 잣나무림 모두 시업구가 비시업구보다 수목의 pH완충효과가 더 발휘되는 것으로 분석되었다. 2)비시업구에서 총수관통과우의 pH=0.735${\times}$초기수관통과우의 pH+1.849($R^2\;=\;0.82$)이었고, 시업구에서 총수관통과우의 pH = 0.863${\times}$초기수관통과우의 PH+1.0242 ($R^2\;=\;0.87$)이었다. 또한, 비시 업구에서 총수간유하수의 pH=0.58${\times}$초기수간유하수의 pH+2.7709 ($R^2\;=\;0.64$)이었고, 시업구에서 총수간유하수의 pH=0.5854${\times}$초기수간유하수의 pH+2.7046 ($R^2\;=\;0.65$)이었다. 3) 초기수관통과우, 총수관통과우에서 평균전기전도도는 전나무림 비시업구>전나무림 시업구>잣나무림 비시업구>잣나무림 시업구의 순이었다. 4)비시업구에서 총수관통과우의 전기전도도=0.4046${\times}$초기수관통과우의 전기전도도+26.766 ($R^2\;=\;0.69$)이었고, 시업구에서 총수관통과우의 전기전도도=0.6002${\times}$초기수관통과우의 전기전도도+8.0184 ($R^2\;=\;0.54$)이었다. 또한, 비시업구에서 총수간유하수의 전기전도도=0.6298${\times}$초기수간유하수의 전기전도도+11.582 ($R^2\;=\;0.72$)이었고, 시업구에서 총수간유하수의 전기전도도=0.602${\times}$초기수간유하수의 전기전도도+20.783 ($R^2\;=\;0.49$)이었다.

Bacillus thuringiensis serovar israelensis 4Q1로부터 분리된 plasmid 제한효소지도 작성 (Restriction endonuclease maps of three plasmids from bacillus thuringiensis serovar israelensis 4Q1)

  • ;이영근;강석권
    • 미생물학회지
    • /
    • 제23권2호
    • /
    • pp.122-128
    • /
    • 1985
  • Bacillus thuringiensis serovar israelensis 4Q1 contains 8 different covalently closed-circular (CCC) plasmids of molecular weight 204, 267, 109, 103, 16, 7.6, 6.4, and 5.0kb. The three smallest plasmids, designated pBti6, and pBti8 may prove to be useful as cloning vectors because of thier size and ease of isolation. The three plasmids were incubated separately with 9 different restriction enzymes and 7 of the enzymes tested cleaved one or more of the plasmids. Plasmid pBti6 has a single site for Bg1 II, Pst I and Pvu II, two sites for Bc1 I and Eco RI, and five sites for Hind III. Plasmid pBti7 has a single site for Bam HI and Pst I, two sites for Hind III, and three sites for PvuII. Plasmic pBti8 has a single site for Bam HI, BelI and Hind III, two sites for Eco RI, and three sites for Bgl II and Pvu II. Composite restriction enzyme maps for pBti6, pBti7 and pBti8 were constructed. The sites of restriction enzyme cleavage were determined by single, double and partial digests of the plasmid DNA. All the restriction sites were aligned relative to the single Bgl II(pBti6), Pst I(pBti7) or Hind III(pBti8) site, respectively.

  • PDF

수용액 내 캐올리나이트와 할로이사이트의 표면화학 특성: 표면복합반응 모델링 (Surface Chemical Properties of Aqueous Kaolinite and Halloysite: Surface Complexation Modeling)

  • 장세정;김수진
    • 한국광물학회지
    • /
    • 제17권2호
    • /
    • pp.157-168
    • /
    • 2004
  • 수용액 내 캐올리나이트와 할로이사이트의 표면화학 특성을 전위차 적정 실험과 FITEQL3.2 프로그램을 이용하여 연구하였다. 표면복합반응 모델 중 일정용량 모델을 적용하였으며, 표면을 사면체 자리와 팔면체 자리로 나누어 설정한 2 sites - 3 $pK_{a/s}$ 모델은 캐올리나이트와 할로이사이트의 표면화학 특성을 설명하는데 적합하였다. 두 점토광물 표면은 pH 4 이상에서 음전하를 띄며 pH가 높아질수록 양성자 표면 전하 밀도는 낮아진다. 산성 및 중성 영역에선 Si 사리(≡$SiO^{-}$ )가, 염기성 영역에선 Al 자리(≡$AlO^{-}$)가 양이온을 흡착하는데 중요한 역할을 할 것으로 예상된다. 모델링 결과 캐올리나이트의 경우 $pK_{a2(si)}$ /$^{int}$, p $K_{al(Al) }$ /$^{int}$ /, $pK_{a2}$ $(Al)^{int}$ /는 각각 4.436. 4.564, 및 8.461이며, 할로이사이트의 경우는 각각 7.852, 3.885, 7.084이다. 캐올리나이트의 총 Si 표면자리 농도와 총 Al 표면자리 농도는 0.215와 0.148 mM이며, 할로이사이트의 경우는 0.357과 0.246 mM이다 두 광물 모두 Si 표면자리 밀도 : Al 표면자리 밀도가 1 : 0.69로 비슷하다. 캐올리나이트의 총 표면자리 밀도는 3.774 sites/$nm^2$로 할로이사이트의 2.292 sites/n $m^2$ 값보다 약 1.6배정도 높다.다.

Preincubation without attB DNA inhibits In Vitro Integrative Recombination of P 1 Mutant attP DNA of Bacteriophage Lambda

  • Yoo, Seung-Ku
    • Journal of Microbiology and Biotechnology
    • /
    • 제5권3호
    • /
    • pp.132-137
    • /
    • 1995
  • The lambda integrase (lnt) is believed to bind to several arm and core sites of attP DNA in order to facilitate intasome formation. We have done systematic mutagenic analysis on all 5 arm sites and found that P1 is absolutely required for integration while P2 is not. We also found that all 3 P' arm sites(P'1, P'2, and P'3) are required for efficient integrative recombination. P'1, which is an important binding site for excision, also seems to be crucial for integration when preincubation of attP DNA with Int and IHF is performed before recombination. Preincubation assay revealed that preincubation with Int and IHF improved the efficiency of recombination of wild type attP DNA and demolished recombinations of P'1 mutant attP DNAs.

  • PDF

부산지역 강우의 화학적 특성 I. pH 및 주요이온의 시ㆍ공간적 변화 (Chemical Characteristics of Precipitation in Pusan I. Temporal and spatial variation of pH and major ions)

  • 전은주;양한섭;옥곤;김영섭
    • 한국환경과학회지
    • /
    • 제7권5호
    • /
    • pp.707-716
    • /
    • 1998
  • The chemical characteristics of precipitation was investigated in Pusan area. Samples were collected from January to November in 1996 at 4 sites, and analyzed pH, major soluble ionic components(C $l^{[-10]}$ , N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$, N $a^{+}$, $K^{+}$, N $H_4$$^{+}$, $Mg^{2+}$, $Ca^{2+}$). The order of anion and cation concentrations for the initial precipitation were C $l^{[-10]}$ > S $O_4$$^{2-}$ > N $O_3$$^{[-10]}$ , and $Ca^{2+}$ > N $a^{+}$ > N $H_4$$^{+}$$Mg^{2+}$$K^{+}$, respectively. At coastal sites(P1 and P2) C $l^{[-10]}$ and N $a^{+}$ of maritime sources (seasalt) were high, but at inland sites(P3 and P4) nss-C $a^{2+}$ and nss-S $O_4$$^{2-}$ were high. Calcium ion for the initial precipitation showed high value of enrichement factor(EF) relative to seawater composition. The contribution of seasalt to the composition of precipitation was higher at bite P1 (53.5%) than those of the other sites. Throughout the year the concentrations of major ions for the initial precipitation were low in the heavy rain season. The mean pH for the initial precipitation was 5.4 and showed the negative relationship with the precipitaion amount. The S $O_4$$^{2-}$ and N $O_3$$^{[-10]}$ do not play an important role in rain acidification due to the high(97%) neutralizing effect of amonia and calcium species.and calcium species.

  • PDF

태안과 강릉지역 여름철 PM10의 수용성 성분 특성 (Characteristic of Water-soluble Components of PM10 at Taean and Gangneung Sites in Summer Season)

  • 박승식;고재민;정창훈
    • 한국대기환경학회지
    • /
    • 제27권3호
    • /
    • pp.291-302
    • /
    • 2011
  • [ $PM_{10}$ ]measurements were made at two coastal sites, i.e., Taean and Gangneung, for summer to examine the characterization of water-soluble organic carbon (WSOC) and inorganic ionic species, and to investigate their difference between the sites. The fractions of three major inorganic water-soluble components ($NO_3^-$, $SO_4^{2-}$, and $NH_4^+$) at Taean and Gangneung sites were 30.6% (16.2~62.0%) and 25.6% (13.0~52.5%) of the $PM_{10}$, respectively. $SO_4^{2-}$ is the most dominant species of water-soluble ions at both sites, accounting for up to 20.5% (9.1~44.9%) and 16.3% (5.5~34.2%) of their respective PM10 mass concentrations. Using the paired T-test, $PM_{10}$ (p<0.01), $NO_3^-$ (p<0.05), $SO_4^{2-}$ (p<0.01), $NH_4^+$ (p<0.001), and WSOC (p<0.05) concentrations exhibited strong fluctuations on a daily basis between Taean and Gangneung sites. Relationship between the concentrations of $SO_x$ ($SO_4^{2-}+SO_2$) and CO indicates that the slopes of $SO_x$ /CO were 0.007 and 0.019 in the Taean and Gangneung sites, respectively. The smaller $SO_x$/CO slope in the Taean site could be related to the aged air with wet scavenging of $SO_x$ during transport. The correlation between the concentrations of CO and WSOC suggests that WSOC observed in the Gangneung ($R^2$=0.82) be transported from combustion-related sources, while the WSOC at the Taean site could be formed through atmospheric processing of primary volatile organic species during transport.

경상북도 문경시 폐탄광 산림복구지 토양의 화학적 특성 (Characteristics of Soil Chemical Properties in Abandoned Coal Mine Forest Rehabilitation Areas in Mungyeong, Gyeongsangbuk-do)

  • 정문호;심연식;김태혁;오지영;정영상
    • 한국토양비료학회지
    • /
    • 제45권5호
    • /
    • pp.733-737
    • /
    • 2012
  • The objectives of this study were to investigate soil chemical properties for forest rehabilitation and suggest design and management in abandoned coal mine areas in Mungyeong, Gyeongsangbuk-do. Total study sites were 10 sites, and soil analysis particular were soil pH, TOC, total-N, C/N ratio, A.v. $P_2O_5$, and CEC. Because most of study sites showed soil pH from 5.0 to 7.0, it seems that soil pH does not affect growth of vegetation. But soil pH in Danbong1 was acidic (pH 4.6), so it is needed to improve with ameliorant such as limestone. Most of study sites is necessary to manage for organic matter and Nitrogen, because there sites showed lower value of TOC and total-N than general forest. The values of A.v. $P_2O_5$ and CEC were good in most of study sites, so it seems that they do not have effect on vegetation growth. All of soil factors has no regression according to elapsed time after rehabilitation. TOC, total-N and A.v. $P_2O_5$ among soil properties have positive relationship between each other. It is necessary to fertilizer for organic matter and Nitroge because of value in TOC, total-N and C/N ratio. The results of this study were analyzed only one time. So, long-term monitoring for soil properties is important for the correct forest rehabilitation and management.

유전자 재조합 대장균을 사용한 Alpha-interferon의 생산과 분비: 제 1 부. 발현벡터의 제작 (Extracellular Production of Alpha-Interferon by Recombinant Escherichia coli : Part I. Construction of Expression Vectors)

  • 노갑수;최차용
    • KSBB Journal
    • /
    • 제5권1호
    • /
    • pp.49-58
    • /
    • 1990
  • 대장균으로부터 alpha interferon의 생산과 분비를 유도하기 위해 대장균의 lipoprotein promoter, lactose promoter 및 operator와 lipoprotein의 signal seqquence를 가지는 vector에 alpha-IFN유전자를 cloning하여 발현 vector pIF-III-B와 vector pIF-III-C를 제작하였다.

  • PDF

산성강하물과 해송엽 엽록소의 관련성 (Relation of Acid Depositions and Chlorophyll Concentration in the Pinus thunbergii Leaf)

  • 이총규;김종갑;황진형
    • 농업생명과학연구
    • /
    • 제45권2호
    • /
    • pp.35-41
    • /
    • 2011
  • 본 연구는 공단지역과 도시지역의 산성강하물과 해송엽의 엽록소 함량과 관련성이 있는 인자를 조사하여 그 관련성을 분석하였다. 해송 임분의 수관통과우 pH는 공단지역이 pH 4.20이었고, 도시지역이 pH 4.87이었다. 공단지역과 도시지역의 해송엽의 엽록소 전체 함량은 각각 0.5984와 0.6784로서 공단지역에서 함량이 낮았다. 지역별 $SO_2$농도는 공단지역이 0.029 ppm, $NO_2$농도는 도시지역이 0.021 ppm이었다. 해송엽의 엽록소 함량과 산성강하물의 인자 상호간의 상관은 pH (r=-0.8769), ${NO_3}^-$ (r=0.6983), ${SO_4}^{2-}$ (r=0.8929)이온, $SO_2$ (r=0.8738), $NO_2$ (r=0.8523)이었다 (p<0.01). 해송엽의 엽록소 함량 (Y)에 관여하는 인자의 회귀 방정식은 Y=4.8979 + 0.7698pH + $0.8412{SO_4}^2$ + $0.8673SO_2$, + $0.8767NO_2$+ $0.8767{NO_3}^-$ ($r^2$=0.8873)이었고, 이때의 설명력은 88%이었다.

Modulation of Kex2p Cleavage Site for In Vitro Processing of Recombinant Proteins Produced by Saccharomyces cerevisiae

  • Mi-Jin Kim;Se-Lin Park;Seung Hwa Kim;Hyun-Joo Park;Bong Hyun Sung;Jung-Hoon Sohn;Jung-Hoon Bae
    • Journal of Microbiology and Biotechnology
    • /
    • 제33권11호
    • /
    • pp.1513-1520
    • /
    • 2023
  • Kex2 protease (Kex2p) is a membrane-bound serine protease responsible for the proteolytic maturation of various secretory proteins by cleaving after dibasic residues in the late Golgi network. In this study, we present an application of Kex2p as an alternative endoprotease for the in vitro processing of recombinant fusion proteins produced by the yeast Saccharomyces cerevisiae. The proteins were expressed with a fusion partner connected by a Kex2p cleavage sequence for enhanced expression and easy purification. To avoid in vivo processing of fusion proteins by Kex2p during secretion and to guarantee efficient removal of the fusion partners by in vitro Kex2p processing, P1', P2', P4, and P3 sites of Kex2p cleavage sites were elaborately manipulated. The general use of Kex2p in recombinant protein production was confirmed using several recombinant proteins.