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Modeling of thermal fluidized desorption for diesel-oil contaminated soils (Diesel-oil에 오염된 토양의 유동상 열탈착 모델링)

  • 이상화;김병욱;이상득;박달근;이중기
    • Journal of Korea Soil Environment Society
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    • v.4 no.2
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    • pp.137-147
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    • 1999
  • Fluidized-bed thermal desorber coupled with a heat pipe was investigated for the remediation of soil contaminated with diesel oils. Thermal gravimetric analysis by Cahn-balance indicated that the desorption of diesel oils from the soil particles was mainly governed by the internal diffusion at low concentration of less than 0.5 wt. % of oils in the soil particles. In fluidized-bed experiments. increase of fluidizing gas velocity reduced the residual oils of the contaminated soils, the increase of soil feed rate decreased efficiency of fluidized-bed desorber. A mathematical model was developed by incorporating Fickian diffusion kinetics into the Kunii-Levenspiel model Simulation results showed reasonable agreement for the performance of fluidized-bed thermal desorber.

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Heat Exchange Performance of Improved Heat Recovery System (개량형 열회수 시스템의 열교환 성능)

  • Suh, Won-Myung;Yoon, Yong-Cheol;Kwon, Jin-Keun
    • Journal of Bio-Environment Control
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    • v.12 no.3
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    • pp.107-113
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    • 2003
  • This study was carried out to improve the performance of pre-developed heat recovery devices attached to exhaust-gas flue connected to combustion chamber of greenhouse heating system. Four different units were compared in the aspect of heat recovery performance; A-, B-, and C-types are exactly the same with the old ones reported in previous studies. D-type newly developed in this experiment is mainly different with the old ones in its heat exchange area and tube thickness. But airflow direction(U-turn) and pipe arrangement are similar with previous three types. The results are summarized as follows; 1. System performances in the aspect of heat recovery efficiency were estimated as 42.2% for A-type, 40.6% for B-type, 54.4% for C-type, and 69.2% for D-type. 2. There was not significant improvement of heat recovering efficiency between two different airflow directions inside the heat exchange system. But considering current technical conditions, straight air flow pattern has more advantage than hair-pin How pattern (U-turn f1ow). 3. The main factors influencing on heat recovery efficiency were presumably verified to be the total area of heat exchange surface, the thickness of ail-flow pipes, and the convective heat transfer coefficient influenced by airflow velocity under the conditions of allowable pipe durability and safety. 4. Desirable blower capacity for each type of heat recovery units were significantly different to each other. Therefore, the optimum airflow capacity should be determined by considering in economic aspect of electricity required together with the optimum heat recovery performance of given heat recovery systems.

Study on the Manufacturing Process of Complex Oxide by Co-Roasting Process and Magnetic Properties Mn-Zn Ferrite (분무 배소법에 의한 복합산화물의 제조공정 및 Mn-Zn ferrite의 자기 특성에 관한연구)

  • 유재근;이경익;이성수
    • Resources Recycling
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    • v.8 no.4
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    • pp.45-56
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    • 1999
  • The purpose of tlus sludy was to preparc raw material powder for Mn-Zn iclrile, h m mined mill scale and fero-Mn, usins a co-spray roasting process The mill scale and ferra-Mn uscd in this raalins process was rcf~nedb y mesn-ns of a slxc~apl rxcss ~nvolvinm~a te~ialsc ontalning imp~u-ltleso r less than 100 pprn In this study an effeclive spray roaster system. wllich produces fme complex oxide powder, collects produccd ~owder.,m d prcvel~tse ~~llssiooifi HCI gas. was also manufactured. By means of spray~ngp urifcd raw malerial solu~lionl nln a manufacued high tcmpervture rumace. &-ferrite powder and a comnpleu o ~ d e powder of Fe,O; and M,x203 were manufactured. The chmcterlstics of the composllion. surface urca, and p'miicle size dismbulion or the produced powder were exmined. ptoduced powdcr was then ~ m e dwi tli ZnO powder. aid olher addilives of defined cornposnion, and Mn-Zn femite cares werc praiuccil by meuns of Sorlning and closely controlled sintering processes. The magpelic p~oprlieso f c olo~ss, initlal permeability. mauin~u~mnn agnehc flux. coz~civcr orcc and residual magnccic flux for the above cores we,= measured, and fmm Il~ase I-csulls the eflicacy of lhe co-spray roasling pncess to pl.ellare raw material powder lor Mn-Zn ferntc was established

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Antiplatelet Activity of [5-(2-Methoxy-5-chlorophenyl)furan-2-ylcarbonyl]guanidine (KR-32570), a Novel Sodium/hydrogen Exchanger-1 and Its Mechanism of Action

  • Lee Kyung-Sup;Park Jung-Woo;Jin Yong-Ri;Jung In-Sang;Cho Mi-Ra;Yi Kyu-Yang;Yoo Sung-Eun;Chung Hun-Jong;Yun Yeo-Pyo;Park Tae-Kyu;Shin Hwa-Sup
    • Archives of Pharmacal Research
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    • v.29 no.5
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    • pp.375-383
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    • 2006
  • The anti platelet effects of a novel guanidine derivative, KR-32570 ([5-(2-methoxy-5-chlorophenyl) furan-2-ylcarbonyl]guanidine), were investigated with an emphasis on the mechanisms underlying its inhibition of collagen-induced platelet aggregation. KR-32570 significantly inhibited the aggregation of washed rabbit platelets induced by collagen $(10{\mu}g/mL)$, thrombin (0.05 U/mL), arachidonic acid $(100{\mu}M)$, a thromboxane (TX) $A_2$ mimetic agent U46619 (9,11-dideoxy-9,11-methanoepoxy-prostaglandin $F_2,\;1{\mu}M$) and a $Ca^{2+}$ ATPase inhibitor thapsigargin $(0.5{\mu}M)$ ($IC_{50}$ values: $13.8{\pm}1.8,\;26.3{\pm}1.2,\;8.5{\pm}0.9,\;4.3{\pm}1.7\;and\;49.8{\pm}1.4{\mu}M$, respectively). KR-32570 inhibited the collagen-induced liberation of $[^3H]$arachidonic acid from the platelets in a concentration dependent manner with complete inhibition being observed at $50{\mu}M$. The $TXA_2$ synthase assay showed that KR-32570 also inhibited the conversion of the substrate $PGH_2$ to $TXB_2$ at all concentrations. Furthermore, KR-32570 significantly inhibited the $[Ca^{2+}]_i$ mobilization induced by collagen at $50{\mu}M$, which is the concentration that completely inhibits platelet aggregation. KR-32570 also decreased the level of collagen $(10{\mu}g/mL)$induced secretion of serotonin from the dense-granule contents of platelets, and inhibited the NHE-1-mediated rabbit platelet swelling induced by intracellular acidification. These results suggest that the antiplatelet activity of KR-32570 against collagen-induced platelet aggregation is mediated mainly by inhibiting the release of arachidonic acid, $TXA_2$ synthase, the mobilization of cytosolic $Ca^{2+}$ and NHE-1.

Growth Responses of 4 Species to NaCl Concentration in Artificial Soil (NaCl 농도별 토양 처리에 대한 4수종의 생장 반응)

  • Park, Woo-Jin;Seo, Byung-Soo;Park, Chong-Min;Choi, Chung-Ho;Choi, Soo-Min
    • Korean Journal of Environment and Ecology
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    • v.24 no.6
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    • pp.735-743
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    • 2010
  • In order to inspect growth responses of Fraxinus rhynchophylla Hance, Koelreuteria paniculata Laxmann, Quercus acutissima Carruther and Ulmus parvifolia Jacquin to NaCl treatment, NaCl solution was treated for four months with 0, 25, 50, 100 and 200 mM concentrations, then survival rate, change of relative growth rate, weight, dry weight and pigment content of leaf were investigated. According to NaCl treatment, pH and EC (electrical conductivity) of soil increased, and growth rates of four tree species fell apparently as treatment time became longer. U. parvifolia had the highest survival rate with 15% in the 200mM treatment, and the other three species withered in the treatment. Relative growth rate, weight and dry weight decreased when NaCl treatment time grew longer. The total chlorophyll declined after it rose to 60 days, and the total chlorophyll and carotenoid of the all species according to NaCl treatment did not change very much. With the result from anlayzing growth responses of four tree species to oxidative stress which occurs during NaCl treatment, U. parvifolia has the highest tolerance, followed by K. paniculata, F. rhynchophylla and Q. acutissima.

Vergleich des Zeichens von C. S. Peirce mit dem von W. v. Humboldt (퍼스와 훔볼트의 기호관 비교)

  • An Cheung-O
    • Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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    • v.3
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    • pp.35-55
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    • 2001
  • In der Semiotik ist es sehr wichtig, den Rahmenbereich des Zeichens festzustellen, weil der Bereich des Zeichens je nach Wissenschaftler unterschiedlich ist. Dementsprechend muss jedes Forschungsergebnis in der Semiotik hinterfragt werden, um sichergehen zu $k\"{o}nnen$, ob es zur Semiotik $geh\"{o}rt$ oder nicht. Daher besteht $zun\"{a}chst$ die Notwendigkeit, zu bestimmen, was ein Zeichen ist. In diesem Zusammenhang versuchten wir in diesem Aufsatz, damit wir den Begriff 'Zeichen' besser erfassen $k\"{o}nnen$. das Zeichen von C. S. Peirce mit dem van W. v. Humboldt zu vergleichen. Zu Beginn dieses Aufsatzes stellten wir dar, was ein Zeichen ist. Dieser Vorgang ist notwendig, damit mit Hilfe des allgemeinen Begriffes des Zeichens ein Vergleich zwischen Peirce und Humboldt angestellt werden kann. Danach stellten wir die Zeichentheorie von Peirce vor. Nach Peirce ist die Sprache eine Untergattung von drei Zeichensorten, die Ikon, Index und Symbol genannt werden. Nach ihm gehbrt das Symbol zur Sprache. $F\"{u}r$ ihn ist der Interpretant im Zeichenbegriff am wichtigsten, weil ein Zeichen immer eines Interpretantes bedarf, der das Zeichen interpretiert. Aber der Interpretant ist kein Individuum, sondern ein interpretierendes $Bewu{\ss}tsein$, also eine traditionelle Gesellschaft, die ein Muster zum Interpretieren bietet. $Anschlie{\ss}end\;besch\"{a}ftigten$ wir uns mit der Theorie von Humboldt. Er benutzt verschiedene Zeichenbegriffe wie z.B. Schriftzeichen, Lautzeichen, Sprachzeichen, grammatische Zeichen, $h\"{o}rbare$ Zeichen, zeitliche Zeichen und $r\"{a}umliche$ Zeichen. Bei ihm ist die Unterscheidung zwischen Wort und Zeichen besonders wichtig, weil das Wort nicht zum Zeichen $geh\"{o}rt$, wie wir es normalerweise annehmen. Er behauptet, dass das Wort beim Produzieren motiviert ist. Daher ist nach ihm das Wort transsemiotisch. $Dar\"{u}ber$ hinaus muss das Zeichen und das Wort im Zusammenhang zwischen Sprache und Denken betrachtet werden. Wenn man das Wort als Zeichen betrachtet, ist das Wort ein Zwischending zwischen dem Sprechenden und dem Ding. Damit $k\"{o}nnen$ wir schlussfolgern; 1) Bei Humboldt ist das Zeichen em Mittel zum Denken, das sich vom transsemiotischen Wort unterscheidet. 2) Nach Peirce besteht ein Zeichen aus Ikon, Index und Symbol. Im Zeichen, das aus Reprasentamen, Interpretant und Objekt besteht, ist der Interpretant am wichtigsten, denn ein Zeichen, dass keinen Interpretant hat, ist kein Zeichen mehr, das interpretierbar ist.

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Design Optimization of Duplex Burnable Poison Rods and Feasibility Evaluation for Core Design (이중구조 가연성독봉 설계안의 최적화 및 노심 핵설계 타당성 평가)

  • Yoon Seok-Kyun;Lee Dae-Jin;Kim Myung-Hyun
    • Journal of Energy Engineering
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    • v.13 no.4
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    • pp.242-258
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    • 2004
  • The duplex burnable poison absorbers concept was suggested by Korea Atomic Energy Research Institute. This BP rod is composed of inner region of natural U-Gd$_2$O$_3$ and outer shell of enriched UO$_2$-Er$_2$O$_3$. It is expected that this burnable absorber has same reactivity control capability with gadolinia burnable absorber used in extened fuel cycle. In order to evaluate the nuclear feasibility of duplex BPs, the nuclear design characteristics were compared with that of four types of burnable absorbers; gadolinia, erbia, IFBA, dysprosia duplex BP on 24 months fuel cycle for Korean Standard Nuclear Power plants. According to the evaluation results of nuclear characteristics, the duplex BPs were better than other BPs on k-infinitives, reactivity holddown worth (RHW), pin power peaking and moderator temperature coefficient (MTC). The possibility of nuclear core design was also confirmed based on the optimized fuel assemblies which were searched for a sensitivity analysis. Characteristics of core design with duplex BPs was compared with that of reference core with gadolinia BPs for cycle length, power peaking and MTC. The duplex BP core had a little longer cycle length by 4 to 7 days because of increased amount of fissile in enriched uranium at the outer shell of duplex BP In case of power peaking F$\_$Q/ of duplex BP core was reduced from 1.5773 to 1.5335. MTC was also less -0.48 pcm/C than that of reference core. Finally, evaluation of fuel cycle economy was performed for the manufacturing feasibility test and fuel cost evaluation with duplex BPs. Fuel cycle economy of duplex BP core almost was equivalent with that of gadolinia BP core.

Double-Chambered Right Ventricle in an Old Standard Poodle Dog

  • Yunho Jeong;Yoonhwan Kim;Eunchan Lee;Ju-Hyun An;Sooyoung Choi;Jin-Young Chung;Jin-Ok Ahn
    • Journal of Veterinary Clinics
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    • v.40 no.2
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    • pp.130-134
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    • 2023
  • A 12-year-old Standard Poodle presented with intermittent weakness and occasional dyspnea at the Veterinary Medicine Teaching Hospital of Kangwon National University. A grade of 4 out of 6 systolic murmur with an irregular tachycardic rhythm was auscultated on both sides of the chest. Systolic blood pressure was 140 mmHg. Panting was noticed in the hospital, but there was no crackle sound. Blood analysis revealed mild increases in liver panel levels (alanine aminotransferase 149 [reference interval, 19-70] U/L; and alkaline phosphatase, 185 [reference interval, 15-127] U/L) and severe increases in cardiac biomarker levels (n-terminal pro-brain natriuretic peptide, 4169 [reference interval, 50-900] pmol/L; and cardiac troponin I, 0.22 [reference interval, 0.03-0.12] ng/mL). On electrocardiography, irregularly irregular supraventricular tachycardic rhythm with an f-wave and no distinct p-wave was observed. Generalized cardiomegaly with an enlarged right atrium and left ventricle was confirmed on thoracic radiography. Moreover, hepatomegaly and an enlarged caudal vena cava were observed. Echocardiographic evaluation revealed a fibromuscular diaphragm in the right ventricle. Because of the obstructive lesion in the right ventricle, the right atrium and ventricle were enlarged (right atrial area index, 38.82 cm2/m2 [reference interval, 4.2-10.2 cm2/m2]; right ventricle end-diastolic area index, 14.152 cm2/m2 [reference interval, 4.9-10.92 cm2/m2]). Accordingly, the patient was diagnosed with double-chambered right ventricle (DCRV). Pimobendan, furosemide, enalapril, diltiazem, and S-adenosylmethionine (SAMe) were prescribed, and all symptoms were relieved. DCRV is a right-sided congenital heart defect resembling pulmonic valve stenosis. If symptoms are not severe, medical therapy can be facilitated without surgery or the balloon dilation.

Analysis of whole genome sequencing and virulence factors of Vibrio vulnificus 1908-10 isolated from sea water at Gadeok island coast

  • Hee-kyung Oh;Nameun Kim;Do-Hyung Kim;Hye-Young Shin;Eun-Woo Lee;Sung-Hwan Eom;Young-Mog Kim
    • Fisheries and Aquatic Sciences
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    • v.26 no.9
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    • pp.558-568
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    • 2023
  • Vibrio vulnificus is an aquatic bacterium causing septicemia and wound infection in humans. To understand this pathogen at the genomic level, it was performed whole genome sequencing of a cefoxitin-resistant strain, V. vulnificus 1908-10 possessing virulence-related genes (vvhA, viuB, and vcgC) isolated from Gadeok island coastal seawater in South Korea. The genome of V. vulnificus 1908-10 consisted of two circular contigs and no plasmid. The total genome size was estimated to be 5,018,425 bp with a guanine-cytosine (GC) content of 46.9%. We found 119 tRNA and 34 rRNA genes respectively in the genome, along with 4,352 predicted protein sequences. Virulence factor (VF) analysis further revealed that V. vulnificus 1908-10 possess various virulence genes in classes of adherence, antiphagocytosis, chemotaxis and motility, iron uptake, quorum sensing, secretion system, and toxin. In the comparison of the presence/absence of virulence genes, V. vulnificus 1908-10 had fur, hlyU, luxS, ompU, pilA, pilF, rtxA, rtxC, and vvhA. Of the 30 V. vulnificus comparative strains, 80% of the C-genotype strains have all of these genes, whereas 40% of the E-genotype strains have all of them. In particular, pilA were identified in 80% of the C-type strains and 40% of the E-type strains, showing more difference than other genes. Therefore, V. vulnificus 1908-10 had similar VF characteristics to those of type C strains. Multifunctional-autoprocessing repeats-in-toxin (MARTX) toxin of V. vulnificus 1908-10 contained 8 A-type repeats (GXXGXXXXXG), 25 B.1-type repeats (TXVGXGXX), 18 B2-type repeats (GGXGXDXXX), and 7 C-type repeats (GGXGXDXXX). The National Center for Biotechnology Information (NCBI) Basic Local Alignment Search Tool (BLAST) showed that the RtxA protein of V. vulnificus 1908-10 had the effector domain in the order of cross-liking domain (ACD)-C58_PaToxP-like domain- α/β hydrolase-C58_PaToxP-like domain.

Synthesis and Properties of 1,4-Diboracyclohexene-2 Derivatives (1,4-Dibora-2-cyclohexene 유도체들의 합성과 그 성질)

  • Uhm, Jae-Kook;Hu D.;Zenneek U.;Pritzkow H.;Siebert W.
    • Journal of the Korean Chemical Society
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    • v.34 no.5
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    • pp.490-497
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    • 1990
  • Two synthetic routes for the 1,4-diboracyclohexene-2 ring 8 have been developed. Method i) starts with 1,2-bis(dichloroaluminyl)ethane, in which the AlCl$_2$ group is replaced by BCl$_2$. Exchange of the chlorine with BI$_3$ in 1,2-bis-(dichloroboryl)ethane yields the corresponding iodo compound, which reacts with the alkynes to heterocycles 8a, b in good yield. In method ii) B$_2$Cl$_4$ is added to alkenes, replacement of chlorine with BI$_3$ yields the bis(diiodoboryl)ethane derivatives which undergo redox reactions with alkynes to give 8c, d. The diiodo derivative 8a forms the pyridine adduct 9a, and reacts with ether to give the ethoxy derivative 8f. 8a-d react with AlMe$_3$ to yield the corresponding dimethyl derivatives 8g-j, which give unstable radical anions when treated with potassium in THF. The ESR parameters are reported. In electrochemical experiments irreversible reductions of 8g-j are observed. 8g-j react with (C$_5$H$_5$)Co(C$_2$H$_4$)$_2$ to give the intermediate 16 VE complexes (C$_5$H$_5$)Co(8), in which C-H activation occurs with formation of the corresponding red 1,4-diboracyclohexadiene complexes 10. The X-ray structure analyses of 10h and 10j are reported.

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