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Obstacle Avoidance and Lane Recognition for the Directional Control of Unmanned Vehicle

  • Kim, Chang-Man;Moon, Hee-Chang;Kim, Sang-Gyum;Kim, Jung-Ha
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.34.6-34
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    • 2002
  • 1. Introduction 2. System Configuration 2.1 Control System 2.1.1 Longitudinal control 2.1.2 Lateral control 2.2 Sensor System 2.2.1 Photo interrupt 2.2.2 Ultrasonic sensor 2.3 Vision system 2.4 Communication system 2.4.1 Data communication 2.4.2 Image Communication 3. Test and Result 3.1 Vision test 3.2 Ultrasonic sensor test 4. Conculsion. Acknowledgment References.

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산소-니트로실 착물의 연구 (제2보) 부틸아미드옥심 유도체의 텅스텐 산소-니트로실 착물의 합성과 특성 (Studies of Oxo-Nitrosyl Complexes(Ⅱ) Synthesis and Properties of Tungsten Oxo-Nitrosyl Complexes with Butylamidoxime Derivatives)

  • 노수균;오상오
    • 대한화학회지
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    • 제39권11호
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    • pp.856-862
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    • 1995
  • 본 연구의 텅스텐 옥소-니트로실 착물 $(n-Bu_4N)_2[W_5O_{12}(NO)_2{RC(NH_2)NHO}_2{RC(NH)NO}_2]{R\;=\;(CH_3)CH, CH_3CH_2CH_2,CH_3SCH_2}$은 텅스텐(VI) 다핵 착물 $(n-Bu_4N)_2[W_6O_{19}]$, 텅스텐 디니트로실 단핵 착물 $[W(NO)_2(acac)(CH_3CN)_2](BF_4)$ 및 부틸 아미드옥심 유도체의 반응에서 얻었다. 합성한 착물은 원소분석, 적외선, 전자 흡수 및 핵자기 공명 스펙트럼에 의해 특성을 조사하였다. 전자를 끌어당기는 ${W(NO)_2}^{2+}$ 단위체는 두 개의 이핵체 ${W_2O_5}^{2+}$ 사이의 중심에 삽입되어 오핵종을 이룬다. $(n-Bu_4N)_2[W_5O_{12}(NO)_2{(CH_3)_2CHC(NH_2)NHO}_2/{(CH_3)_2/CHC(NH)NO}_2]$$^1{H} NMR$ 스펙트럼에서 네 개의 이중선이 나타남으로 양성자간의 상호작용이 큰 것을 추정할수있다. $^{13}C$ NMR 스펙트럼은 배위된 네 개의 배위자중 두개의 배위자가 나타남으로 두 배위자의 서로 다른 배위모형과 대칭성에 대한 정보를 준다. ${W(NO_2)}^{2+}$ 단위체는 형식상 시스형이며 기하학적으로 $C_{2v}$ 대칭을 가진다.

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Abscisic acid가 $Cd^{2+}$에 의한 닭의장풀이 생리적 반응에 미치는 영향 (The Effects of Abscisic Acid (ABA) on $Cd^{2+}$-induced Physiological Responses in Commelina communis L.)

  • 이준상
    • 환경생물
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    • 제23권1호
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    • pp.47-51
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    • 2005
  • 3주간 정상적으로 생장한 닭의장풀을 Hoagland 용액 (대조구, 100 μM Cd/sup 2+/, 100 μM Cd/sup 2+/ + 100 μM ABA, 100 μM Cd/sup 2+/+50 mM KCl)에서 1주간 수경재배 한 후 생장, 엽록소 함량, 엽록소 형광, 수분 스트레스와 Cd/sup 2+/의 축적을 조사하여 Cd/sup 2+/ 축적과 식물의 생리적 반응과의 연관성을 찾고자 하였다. 식물의 생장에서 Cd/sup 2+/과 Cd/sup 2+/+ABA 처리구는 대조구에 비해 각각 71%와 81%생장이 감소하였고, Cd/sup 2+/+KCl 처리구는 Cd/sup 2+/ 처리구와 생장에 큰 차이가 없었다. 엽록소 함량은 Cd/sup 2+/, Cd/sup 2+/+ABA, Cd/sup 2+/+KCl 처리구에서 대조구에 비해 각각 32%, 41%, 29% 억제되었다. 엽록소 형광 측정의 경우 Cd/sup 2+/ 처리구는 대조구에 비해 모든 광도에서 Fv/Fm 비율이 14∼20% 감소하였다. Cd/sup 2+/+ABA 처리구는 Fv/Fm 비율이 23% 내외에서 감소하였으며, Cd/sup 2+/+KCl 처리구는 Cd/sup 2+/ 처리구와 Fv/Fm 비율에 큰 차이가 없었다. 수분 스트레스에 대한 Cd/sup 2+/과 ABA 처리 효과는 Cd/sup 2+/ 처리구에서 대조구에 비해 2.5배, Cd/sup 2+/+ABA 처리구에서 3배, Cd/sup 2+/+KCl 처리구에서 2.25배 각각 수분 스트레스가 증가하였다. Cd/sup 2+/ 수송에 대한 ABA의 효과를 살펴보면, Cd/sup 2+/+ABA 처리구에서 ABA는 Cd/sup 2+/ 수송을 억제하거나 촉진시키지는 않았지만 Cd/sup 2+/의 뿌리 축적을 약 13% 심화시켰다. 반면에 KCl은 뿌리 내 Cd/sup 2+/ 축적을 약 60% 억제시켰다. 따라서 대표적인 스트레스 내성 호르몬 ABA는 Cd/sup 2+/축적으로 인해 발생된 식물의 생리적 독성을 완화시켜 주지 못했으며. 오히려 독성을 증가시켰다.

CeO2/TiO2 코어-쉘 나노입자의 합성 (Synthesis of CeO2/TiO2 core-shell Nanoparticles)

  • 문영길;박장우;김상헌
    • 한국응용과학기술학회지
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    • 제34권4호
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    • pp.746-755
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    • 2017
  • 본 연구에서는 $CeO_2$ 표면에 $Ti(SO_4)_2$의 가수 분해를 이용하여 $TiO_2$를 성장시켜 코어-쉘 구조를 가지는 세라믹 나노입자를 합성 하였다. $CeO_2/TiO_2$ 코어-쉘 합성에서는 $CeO_2:TiO_2$의 몰비, 반응 시간, 반응 온도, $CeO_2$ 슬러리 농도, $Ti(SO_4)_2$의 pH 조절을 통하여 코어-쉘 구조를 가지는 최적의 합성 조건을 찾았다. $CeO_2:TiO_2$의 최적의 몰비는 1:0.2~1.1, 최적의 반응 시간은 24 시간, 최적의 $CeO_2$ 슬러리 농도는 1%, 최적의 반응 온도는 $50^{\circ}C$임을 알 수 있었다. $NH_4OH$ 수용액을 이용하여 $Ti(SO_4)_2$ 의 pH를 1로 맞추어 $CeO_2$ 슬러리에 적하하면 10%의 농도를 가지는 $CeO_2$ 슬러리에서도 $CeO_2/TiO_2$ 코어-쉘 나노 입자를 합성할 수 있었다. $80^{\circ}C$이상의 높은 온도에서 반응을 시키면 $CeO_2/TiO_2$ 코어-쉘 구조가 아닌 독립된 $TiO_2$ 나노 입자를 형성함을 알 수 있었다. 최적의 반응 온도는 $50^{\circ}C$로서 가장 좋은 구조의 $CeO_2/TiO_2$ 코어-쉘이 합성되었다.

Synthesis and Characterization of Various Di-N-Functionalized Tetraaza Macrocyclic Copper(II) Complexes

  • Kang, Shin-Geol;Kim, Na-Hee;Lee, Rae-Eun;Jeong, Jong-Hwa
    • Bulletin of the Korean Chemical Society
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    • 제28권10호
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    • pp.1781-1786
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    • 2007
  • Two copper(II) complexes, [CuL3](ClO4)2 bearing one N-CH2CH2CONH2 group as well as one N-CH2CH2CN group and [CuL4](ClO4)2 bearing two N-CH2CH2CONH2 groups, have been prepared by the selective hydrolysis of [CuL2](ClO4)2 (L2 = C-meso-1,8-bis(cyanoethyl)-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). The complex [CuL5](ClO4)2 bearing one N-CH2CH2C(=NH)OCH3 and one N-CH2CH2CN groups has been prepared as the major product from the reaction of [CuL2](ClO4)2 with methanol in the presence of triethylamine. In acidic aqueous solution, the N-CH2CH2C(=NH)OCH3 group of [CuL5](ClO4)2 undergoes hydrolysis to yield [CuL6](ClO4)2 bearing both N-CH2CH2COOCH3 and N-CH2CH2CN groups. The crystal structure of [CuL5](ClO4)2 shows that the complex has a slightly distorted square-pyramidal coordination polyhedron with an apical Cu-N (N-CH2CH2C(=NH)OCH3 group) bond. The apical Cu-N bond distance (2.269(3) A) is ca. 0.06 A longer than the apical Cu-O (N-CH2CH2CONH2 group) bond of [CuL4](ClO4)2. The pendant amide group of [CuL3](ClO4)2 is involved in coordination. The carboxylic ester group of [CuL6](ClO4)2 is also coordinated to the metal ion in various solvents but is removed from the coordination sphere in the solid state.

Endoplasmic Reticulum Ca2+ Store: Regulation of Ca2+ Release and Reuptake by Intracellular and Extracellular Ca2+ in Pancreatic Acinar Cells

  • Kang, Yun Kyung;Park, Myoung Kyu
    • Molecules and Cells
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    • 제19권2호
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    • pp.268-278
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    • 2005
  • We investigated the effect of cytosolic and extracellular $Ca^{2+}$ on $Ca^{2+}$ signals in pancreatic acinar cells by measuring $Ca^{2+}$ concentration in the cytosol($[Ca^{2+}]_c$) and in the lumen of the ER($[Ca^{2+}]_{Lu}$). To control buffers and dye in the cytosol, a patch-clamp microelectrode was employed. Acetylcholine released $Ca^{2+}$ mainly from the basolateral ER-rich part of the cell. The rate of $Ca^{2+}$ release from the ER was highly sensitive to the buffering of $[Ca^{2+}]_c$ whereas ER $Ca^{2+}$ refilling was enhanced by supplying free $Ca^{2+}$ to the cytosol with $[Ca^{2+}]_c$ clamped at resting levels with a patch pipette containing 10 mM BAPTA and 2 mM $Ca^{2+}$. Elevation of extracellular $Ca^{2+}$ to 10 mM from 1 mM raised resting $[Ca^{2+}]_c$ slightly and often generated $[Ca^{2+}]_c$ oscillations in single or clustered cells. Although pancreatic acinar cells are reported to have extracellular $Ca^{2+}$-sensing receptors linked to phospholipase C that mobilize $Ca^{2+}$ from the ER, exposure of cells to 10 mM $Ca^{2+}$ did not decrease $[Ca^{2+}]_{Lu}$ but rather raised it. From these findings we conclude that 1) ER $Ca^{2+}$ release is strictly regulated by feedback inhibition of $[Ca^{2+}]_c$, 2) ER $Ca^{2+}$ refilling is determined by the rate of $Ca^{2+}$ influx and occurs mainly in the tiny subplasmalemmal spaces, 3) extracellular $Ca^{2+}$-induced $[Ca^{2+}]_c$ oscillations appear to be triggered not by activation of extracellular $Ca^{2+}$-sensing receptors but by the ER sensitised by elevated $[Ca^{2+}]_c$ and $[Ca^{2+}]_{Lu}$.

$Bi_2Sr_2CaCu_2O_{8+\delta}$ 고온초전도체의 d-파 대칭성 증거로서의 $Pb/Bi_2Sr_2CaCu_2O_{8+\delta}$접합 투과전도특성 (Tunneling Characteristics in $Pb/Bi_2Sr_2CaCu_2O_{8+\delta}$ Junctions as an Evidence for a d-wave Order Parameter Symmetry in $Bi_2Sr_2CaCu_2O_{8+\delta}$ Superconductors)

  • Chang, Hyun-Sik;Lee, Hu-Jong
    • Progress in Superconductivity
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    • 제2권2호
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    • pp.65-70
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    • 2001
  • $Pb/Bi_2Sr_2CaCu_2O_{8+\delta}$-single-crystal junctions with the tunneling direction along the c axis of the crystal were fabricated to obtain an s-wave-superconductor/d-wave-superconductor Josephson junctions. The tunneling R (T) curves and current-voltage characteristics show distinct features which can be explained only under the assumption that the order parameter of high-$T_c/Bi_2Sr_2CaCu_2O_{8+{\delta}}$ superconductors has a pure d-wave symmetry, which is in contrast to the case of $YBa_2Cu_3O_{7+{\delta$}}$erconductors where a minor s-wave component is also present..

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UV와 $Fe^{2+}$, 그리고 $H_2O_2$를 조합한 고급산화 공정에서의 Pentachlorophenol의 분해 속도 연구 (A Study on the Comparison of Advanced Oxidation Reactions Including UV, $Fe^{2+}$, and $H_2O_2$ for the Degradation of Pentachlorophenol)

  • 손현석;김문경;조경덕
    • 대한환경공학회지
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    • 제29권7호
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    • pp.846-851
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    • 2007
  • 본 연구는 PCP를 UV, $UV/H_2O_2$, $Fe^{2+}$, $Fe^{2+}/H_2O_2$, 그리고 $UV/Fe^{2+}/H_2O_2$의 공정을 이용하여 처리할 저 각각 공정의 처리효율을 비교하여 각 반응의 결합에 의한 개선 효과와 분해 기전을 규명한 연구이다. 실험의 결과 UV 반응에 $H_2O_2$의 첨가에 따라 약 13배 정도의 유사 일차 반응 속도의 증가를 보였으며, $Fe^{2+}$ 단독 반응에 비해 180 mM과 16 mM의 $H_2O_2$의 첨가는 각각 4배와 7.25배의 반응 속도 증가를 보였다. 또한 $Fe^{2+}/H_2O_2$의 반응에 비해 UV를 조사한 반응의 경우 약 3.1배의 반응 속도의 개선을 보였다. 이러한 반응속도의 증가는 각 반응에서 생성되는 OH 라디칼의 생성과 밀접한 관계가 있었다. $Fe^{2+}/H_2O_2$ 반응에서 일어나는 슬러지 침전 반응은 UV를 조사함으로서 상당부분 제거가 가능하였다.

골아세포내 $Ca^{2+}$ 활성도의 조절기전 (Mechanism of $Ca^{2+}$ Regulation in Osteoblast-like Cells)

  • 박미정
    • Journal of Korean Biological Nursing Science
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    • 제1권1호
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    • pp.25-41
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    • 1999
  • Physiological activity of osteoblast including bone formation is known to be closely related to the increase of intracellular $Ca^{2+}$ activity($[Ca^{2+}]_i$) in osteoblast. $Ca^{2+}$ is an important intracellular messenger in diverse cellular functions, and regulation of its level is mediated by the transmembrane $Ca^{2+}$ movement via $Ca^{2+}$ channels, $Na^+-Ca^{2+}$ exchange, and by intracellular $Ca^{2+}$ movement through the intracellular stores. The purpose of this study is to investigate how the intracellular $Ca^{2+}$ is regulated in osteoblast-like cells(OLCs) by measuring $Ca^{2+}$ activity with cell imaging technique. OLCs were isolated from femur and tibia of neonatal rats, and cultured for 7 days. Cultured OLCs were loaded with a $Ca^{2+}$-sensitive fluorescent dye, Fura-2, and fluorescence images were monitored with a cooled CCD camera. The images were processed and analyzed with an image analyzing software. The results were as follows. (1) $[Ca^{2+}]_i$ of OLC decreased as the $Ca^{2+}$ concentration in the superfusing Tyrode solution was lowered. When $Na^+$ concentration in the superfusing solution was decreased, $[Ca^{2+}]_i$ increased.. These suggest that $Ca^{2+}$ flux occurs via the $Na^+-Ca^{2+}$ exchange mechanism. (2) When $Na^+$ in the superfusing solution was removed. a transient $Ca^{2+}$, increase($Ca^{2+}$ spike) was occasionally observed. However, $Ca^{2+}$ spike was not observed after adding 1 ${\mu}M$ thapsigargin. This implies that the generation of $Ca^{2+}$ spike is mediated by the release of $Ca^{2+}$ from endoplasmic reticulum(ER). (3) As the $Ca^{2+}$ concentration in the superfusing solution was raised, the frequency of 0mM $Na^+$-induced $Ca^{2+}$ spike increased, suggesting that $Ca^{2+}$-induced $Ca^{2+}$ release(CICR) mechanism exists. (4) After $[Ca^{2+}]_i$ was decreased with the superfusion of $Ca^{2+}$-free solution containing thapsigargin, the recovery of $[Ca^{2+}]_i$ with reperfusion of 2.5mM $Ca^{2+}$ solution transiently exceeded the control level, suggesting that the depletion of $Ca^{2+}$ in ER induces $Ca^{2+}$ influx from extracellular medium via store-operated $Ca^{2+}$ influx(SOCI) mechanism. (5) $[Ca^{2+}]_i$ was not affected by the superfusion of 25mM $K^+$ Tyrode solution. These results suggest that intracellular $Ca^{2+}$ activity in osteoblast is regulated by transmembrane $Ca^{2+}$ flux via $Na^+-Ca^{2+}$ exchange, $Ca^{2+}$ release from the internal store (ER) via $Ca^{2+}$-induced $Ca^{2+}$ release, and store-operated $Ca^{2+}$ influx across the cell membrane.

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Assembly of Six-Membered Vanadium Borophosphate Cluster Anions: Synthesis and Structures of (NH4)2(C2H10N2)6[BaH2O)5]2[V2P2BO12]6.8H2O and (NH4)8(C3H12N2)4[Ba(H2O)7][V2P2BO12]6.17H2O

  • Yun, Ho-Seop;Do, Jung-Hwan
    • Bulletin of the Korean Chemical Society
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    • 제26권1호
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    • pp.146-150
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    • 2005
  • Two new barium vanadium borophosphate compounds, $(NH_4)_2(C_2H_{10}N_2)_6[Ba(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}8H_2O$, Ba- VBPO1 and $(NH_4)_8(C_3H_{12}N_2)_4[Ba(H_2O)_7][V_2P_2BO_{12}]_6{\cdot}17H_2O$, Ba-VBPO2 have been synthesized by interdiffusion methods in the presence of diprotonated ethylenediamine and 1,3-diaminopropane. Compound Ba-VBPO1 has an infinite chain anion (${[BaH_2O)_5]_2[V_2P_2BO_{12}]_6}$$^{14-}$, whereas Ba-VBPO2 has a discrete cluster anion {[$Ba(H_2O)_7][V_2P_2BO_{12}]_6$}$^{16-}$. Crystal Data: $(NH_4)_2(C_2H_{10}N_2)_6[Ba(H_2O)_5]_2[V_2P_2BO_{12}]_6{\cdot}8H_2O$, triclinic, space group P$\overline{1}$ (no. 2), a = 13.7252(7) $\AA$, b = 15.7548(8) $\AA$, c = 15.8609(8) $\AA$, α = 63.278(1)$^{\circ}$, $\beta$ = 75.707(1)$^{\circ}$, $\gamma$ = 65.881(1)$^{\circ}$, Z = 1; $(NH_4)_8(C_3H_{12}N_2)_4[Ba(H_2O)_7][V_2P_2BO_{12}]_6{\cdot}17H_2O$, monoclinic, space group C2/c (no. 15), a = 31.347(2) $\AA$, b = 17.1221(9) $\AA$, c = 22.3058(1) $\AA$, $\beta$ = 99.303(1)$^{\circ}$, Z = 4.