• 제목/요약/키워드: boron

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두 사막식물(沙漠植物)에 미치는 Boron 의 영향 (Effect of Boron Levels on Two Desert Plant Species)

  • 차종환
    • 한국토양비료학회지
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    • 제6권2호
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    • pp.137-140
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    • 1973
  • 두 사막식물(沙漠植物)을 여러 단계의 Boron level을 가진 수경재배액에 생육(生育)하였다. 두종(種) 모두 Boron의 다량(多量) 축적에 대단한 저항력을 보였다. 그러나 F. dumosa는 영양용액내(內) 10ppm 및 그 이상(以上)의 level에서 상당히 높은 양을 축적하였다. F. dumosa에서 생산량(量) 감소가 50 및 100ppm구(區)에서 나타났다. Boron의 높은 level은 F. dumosa에서 근내(根內) K의 level을 감소시키는 결과(結果)를 가져왔다. A. hyfnenelytra의 생산량은 Boron 20ppm구(區) 까지는 증가되는 경향을 보였다. 그러나 이 level에서 엽내(葉內) Boron의 함량(含量)은 다만 156ppm에 불과했다. 고(高)농도의 Boron은 A. hymeaelytra 엽내(葉內) Boron의 함량(含量)을 점차적으로 증가시키지는 못했다. 사막에서 이들 2종(種)의 분포(分布)는 토양내(內)에 Boron의 많은 양(量)이 존재해서 Boron의 적은 양(量)을 축적하는 그들의 능력에 관계된것 같다.

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활성탄 흡착에 의한 해수중의 보론 제거 (Removal of boron in seawater by activated carbon adsoprtion)

  • 김한승;강준석;김병로
    • 상하수도학회지
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    • 제25권6호
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    • pp.917-922
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    • 2011
  • Adsorption characteristics of boron on activated carbon was investigated in order to evaluate the use of activated carbon for the removal of boron in desalination processes using SWRO. Boron was removed ranging from 54~60% when the concentration of activated carbon was 1,000 mg/L in 6 hours under the initial boron concentration of 5 mg/L. The removal of boron increased by 20~22% with the increase of pH from 5 to 9. Organic matter had adverse effect on the adsorption of boron on activated carbon. Boron removal decreased by 10-12% when EDTA was added at 1 mg/L under 5 mg/L of boron and 200mg/L of activated carbon. In this results, activated carbon would be a good candidate for a pretreatment of desalination processes by SWRO from the view of mitigating the feed boron concentration to RO and meeting the effluent boron concentration without post-treatment after RO.

원자로 기기 열수력 해석 코드에서 붕소 수송 방정식의 구현 (THE IMPLEMENTATION OF BORON TRANSPORT EQUATION INTO A REACTOR COMPONENT ANLAYSIS CODE)

  • 박익규;이승욱;윤한영
    • 한국전산유체공학회지
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    • 제18권4호
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    • pp.53-60
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    • 2013
  • The boron transport model has been implemented into the CUPID code to simulate the boron transport phenomena of the PWR. The boron concentration conservation was confirmed through a simulation of a conceptual boron transport problem in which water with a constant inlet boron concentration injected into an inlet of the 2-dimensional vertical flow tube. The step wise boron transport problem showed that the numerical diffusion of the boron concentration can be reduced by the second order convection scheme. In order to assess the adaptability of the developed boron transport model to the realistic situation, the ROCOM test was simulated by using the CUPID implemented with the boron transportation.

Inhibition of Adventitious Root Growth in Boron-Deficient or Aluminum-Stressed Sunflower Cuttings

  • Hong, Jung-Hee;Go, Eun-Jung;Kim, Tae-Yun
    • 한국환경과학회지
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    • 제12권11호
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    • pp.1189-1196
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    • 2003
  • The effect of boron and aluminum on the development of adventitious roots was studied in sunflower cuttings. Three-day-old seedlings were de-rooted and grown in nutrient solutions with or without boron and supplemented with different concentrations (from 50 to 700 ${\mu}$M) of aluminum. The number and length of the adventitious roots and proline content in adventitious roots in response to insufficient boron and aluminum stress were determined periodically. The micronutrient boron caused the development of numerous roots in the lower parts of the hypocotyl. A dose-response of boron-induced rooting yielded an optimum concentration of 0.1 mM boron. In the absence of boron, in the majority of the adventitious roots, a significant inhibition was observed with or without aluminum, indicating that the most apparent symptom of boron deficiency is the cessation of root growth. Increasing concentrations of aluminum caused progressive inhibition of growth and rooting of the hypocotyls, and a parallel increase in proline levels of adventitious roots. Supplemental boron ameliorated the inhibitory effect of aluminum, suggesting that aluminum could inhibit root growth by inducing boron deficiency. Ascorbate added to medium in the absence of boron improved root growth and induced a significant decrease in proline levels. These findings suggest that adventitious root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

Improving the dielectric reliability using boron doping on solution-processed aluminum oxide

  • Kim, Hyunwoo;Lee, Nayoung;Choi, Byoungdeog
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.411.1-411.1
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    • 2016
  • In this study, we examined the effects of boron doping on the dielectric reliability of solution processed aluminum oxide ($Al_2O_3$). When boron is doped in aluminum oxide, the hysteresis reliability is improved from 0.5 to 0.4 V in comparison with the undoped aluminum oxide. And the accumulation capacitance is increased when boron was doped, which implying the reduction of the thickness of dielectric film. The improved dielectric reliability of boron-doped aluminum oxide is originated from the small ionic radius of boron ion and the stronger bonding strength between boron and oxygen ions than that of between aluminum and oxygen ions. Strong boron-oxygen ion bonding in aluminum oxide results dielectric film denser and thinner. The leakage current of aluminum oxide also reduced when boron was doped in aluminum oxide.

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A STUDY ON THE BEHAVIOR OF BORON DISTRIBUTION IN LOW CARBON STEEL BY PARTICLE TRACKING AUTORADIOGRAPHY

  • Mun, Dong-Jun;Shin, Eun-Joo;Koo, Yang-Mo
    • Nuclear Engineering and Technology
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    • 제43권1호
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    • pp.1-6
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    • 2011
  • The behavior of the non-equilibrium grain boundary segregation of boron in low carbon steel was studied through a particle tracking autoradiography. The behavior of the non-equilibrium grain boundary segregation of boron during continuous cooling was compared with the isothermal kinetics of the non-equilibrium grain boundary segregation of boron at the holding temperature using an effective time method. On the basis of the experiments, the cooling rate dependence of the non-equilibrium segregation of boron was explained using the time dependence of the non-equilibrium segregation of boron in low carbon steel. The experimental observations for the cooling rate dependence of the grain boundary segregation of boron are in good agreement with the time dependence of the grain boundary segregation of boron. The mechanisms of the non-equilibrium segregation of boron during cooling in low carbon steel are also discussed.

Preliminary research on the development of boron neutron capture therapy drugs

  • Soyeon Kim;Ji-ung Yang;Kyo Chul Lee;Jung Young Kim;Yong Jin Lee;Ji-Ae Park
    • 대한방사성의약품학회지
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    • 제7권1호
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    • pp.3-10
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    • 2021
  • For successful boron neutron caputre therapy, it is essential to develop a boron drug with a selective accumulation capacity for tumors. In particular, in order to apply boron neutron caputre therapy to brain tumors, drugs with good blood-brain barrier penetration are required. In this study, two low-molecular-weight boron compounds were introduced as brain tumor boron neutron caputre therapy drugs, and their physical and biological efficacy were evaluated. Among them, B2 showed good blood-brain barrier permeability and a high brain/blood ratio. From these results, it is expected that B2 can be used as a useful boron drug for boron neutron caputre therapy in brain tumors.

Effects of Boron Supplementation to Diets Deficient in Calcium and Phosphorus on Performance with Some Serum, Bone and Fecal Characteristics of Broiler Chickens

  • Bozkurt, Mehmet;Kucukyilmaz, Kamil;Catli, Abdullah Ugur;Cinar, Mustafa;Cabuk, Metin;Bintas, Erol
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권2호
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    • pp.248-255
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    • 2012
  • Three levels of boron (0, 30, 60 ppm) were supplemented in practical corn-soybean based starter and grower diets, containing either adequate or inadequate Ca or P. A total of 1,800, 1-day-old sexed broiler chicks were assigned to six dietary treatments and fed with the experimental diets for 42 days. Boron improved the overall feed conversion ratio, but increased body weight only at 21 days of age (p<0.01). Boron decreased feed intake in the case of feeding on a diet deficient in Ca and P, and tended to increase feed intake when birds received a diet adequate in Ca and P, signifying significant boron by Ca-P interaction (p<0.01). Mortality was not influenced by boron (p>0.05). Dietary Ca and P deprivation reduced body weight and feed consumption significantly, but did not influence the feed conversion ratio and mortality (p>0.05). Serum Ca level, ALP and ALT activities were not influenced either by dietary Ca and P deficiency or boron supplementation. Serum P content increased with respect to boron at 30 ppm. Bone breakage strength was not affected by dietary variables. Tibia ash, Ca and P were increased in response to the supplementation diet with 30 ppm boron, whereas 60 ppm showed no effect in most cases. Accordingly, the dietary boron supplementation of 30 ppm significantly decreased fecal Ca and P excretion, while there was a numerical decline in the 60 ppm boron as compared to the 0 ppm boron group. Data presented herein indicated that boron, either at the 30 ppm or 60 ppm supplementation level, was effective in conversion of feed to body weight, whereas only boron at 30 ppm contributed to the mineralization of bone thereby augmenting more Ca and P while excreting less through faeces.

Neutron Radiography를 이용한 고탄소흑연강에서 붕소 분석 (Boron Analysis in High Carbon Graphitized Steel using Neutron Autoradiography)

  • 우기도;양창호;박희찬;이창희;심철무;장진성;김현경
    • 한국재료학회지
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    • 제11권12호
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    • pp.1074-1079
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    • 2001
  • To study the distribution of boron and the boron effect for nucleation of graphite in high carbon steel, neutron induced autoradiography method is used. High carbon steel is easy to make the graphitization by addition of boron. It is easy to analysis of boron distribution using neutron radiography with neutron fluence of $1.9$\times${\times}10^{13}/cm^2$in the boron added high carbon steel. By the neutron induced autoradiography technique, it was found that the distribution of boron depended on boron content, graphitiging temperature and time. And by the analysis of secondary ion mass spectroscopy (SIMS) and electron probe micro analysis (EPMA), boron or boride were acted at nucleation site of graphite in high carbon steel.

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전기도금법에 의해 생성된 Ni-B 합금도금층의 물성에 미치는 B 함량의 영향 (Influence of B Content on Properties of Ni-B Electrodeposit)

  • 이규환;장도일;권식철
    • 한국표면공학회지
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    • 제37권4호
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    • pp.208-214
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    • 2004
  • The influence of the boron content on the various properties of Ni-B alloy films produced by electrodeposition was investigated. The considerable reduction in grain size was observed with increasing boron content. The internal stress was tensile and increased linearly with increasing boron content. Hardness increased up to $750H_{v}$ at 2 at% boron and then kept the value to 11 at% boron for as-plated Ni-B coatings. The hardness of Ni-B films increased up to $1,250H_{v}$ due to the intermetallic$ Ni_3$B precipitation by the heat treatment, and maximum hardness of each coating increases with boron content. Wear resistance decreased with increasing the boron content because of high friction coefficient and brittle fracture of film which has higher content of boron.