• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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• pp.213-216
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• 2003

This study was conducted to estimate if the level of several chemical ingredients including alkanolamines or ethanolamines (EA) examined in the specific synthetic metalworking fluid (MWF) “A” can cause anti-microbial activity and health effect. Three water-based MWF products (“A”, “B”, and “C”) were studied every week for two months (from June 1, 2002 to July 30, 2002). Chemical ingredients such as formaldehyde, boron, EA, and copper were examined. In the sump where MWF “A” was used, not only the total level of EA, monoethanolamine(MEA), diethanolamine(DEA) and triethanolamine(TEA), but also boron level were significantly higher than those of the other MWFs. ANOVA statistical tests indicated that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF A were significantly higher than those in other MWF types. Correlation tests also found that levels of pH, alkalinity, boron, MEA, DEA and TEA in MWF “A” are significantly correlated. We suggested the assumptions that excessive concentrations of EA, and borate at a high pH level, may cause anti-microbial resistance synergically, To demonstrate this assumption, additional study is needed to examine the relationship between the levels of microbes and excessive concentrations of EA, and borate at a high pH level.

• 한국정보통신학회논문지
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• 제7권5호
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• pp.1032-1037
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• 2003

보론 도핑된 CdS 박막을 chemical bath deposition법으로 증착하고, 도핑농도에 따른 박막의 구조적, 광학적 특성을 조사하였다. 보론 도핑된 CdS 박막은 XRD 분석 결과 (002)면 방향으로 강한 우선성장 방위를 가지며 육방정(hexagonal) 구조로 성장하였다 보론 도핑에 관계없이 모든 시편은 2.3 eV(녹색 발광) 및 1.6 eV(적색 발광) 부근에서 PL peak을 가지며, 도핑 농도가 증가함에 따라 피크 세기는 감소하였다. 보론 도핑에 따라 CdS 박막의 가시광 영역에서의 광투과율은 향상되었고, 밴드 갭은 증가하였다.

• 한국전기전자재료학회논문지
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• 제25권1호
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• pp.6-14
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• 2012

For integrated complementary metal oxide semiconductor (CMOS) circuits, the lateral spread for two-dimensional (2-D) impurity distributions are very important for the analyzing the devices. The measured two-dimensional SEM data obtained using the chemical etching-method matched very well with the results of the Gauss model for boron implanted samples. But the profiles in boron implanted silicon were deviated from the Gauss model. The profiles in boron implanted silicon were shown a little bit steep profile in the deep region due to backscattering effect on the near surface from the bombardments of light boron ions. From the simulated 3-D data obtained using an analytical model, the 1-D and 2-D data were compared with the experimental data and could be verified the justification from the experimental data. The data of 3-D model were also shown good agreements with the experimental and the simulated data. It can be used in the 3-D chip design and the analysis of microelectro-mecanical system (MEMS) and special devices.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.27-30
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• 2002

Boron Phosphide films were deposited on the glass substrate at the low temperature, $550^{\circ}C$, $480^{\circ}C$, by the reaction of $B_{2}H_{6}$, with $PH_{3}$ using CVD. The reactant gas rates were 50 cc/min and 20 cc/min for $B_{2}H_{6}$, 50 cc/min and 40 cc/min for $PH_{3}$ and $1.5\ell$/min for $N_{2}$ carrier gas. The films were annealed for 1hour, 3hours in $N_{2}$ ambient at $550^{\circ}C$ and $400^{\circ}C$. The deposition rate was $1000{\AA}$/min and the refractive index of film was 2.6. From results of XRD measurement the films have the preferred orientation of (1 0 1). For as deposited the film, the data of VIS spectrophotometer show 75.49%, 76.71% for 1hr-annealed and 86.4% for 3hrs-annealed. From AFM datas the surface condition of obtained films are was shown $73{\AA}$, $88.9{\AA}$ and $220{\AA}$ for as-deposited, for 1hr-annealed and for 3hr annealed, respectively.

• Advances in nano research
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• 제11권6호
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• pp.607-620
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• 2021

In this paper, the vibrations of boron nitride nanotubes (BNNTs) are investigated by considering the electric field. To consider the size effect at nanoscale dimensions, the surface elasticity theory is exploited. The equations of motion of the BNNTs are obtained by applying Hamilton's principle, and the clamped-guided boundary conditions are also considered. The governing equations and boundary conditions are discretized using the differential quadrature method (DQM), and the natural frequency is obtained by using the eigenvalue problem solution. The results are compared with the molecular dynamic simulation in order to validate the accurate values of the surface effects. In the molecular dynamics (MD) simulation, the potential between boron and nitride atoms is considered as the Tersoff type. The Timoshenko beam model is adopted to model BNNT. The vibrations of two types of zigzag and armchair BNNTs are considered. In the result section, the effects of chirality, surface elasticity modulus, surface residual tension, surface density, electric field, length, and thickness of BNNT on natural frequency are investigated. According to the results, it should be noted that, as an efficient non-classical continuum mechanic approach, the surface elasticity theory can be used in scrutinizing the dynamic behavior of BNNTs.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 추계학술대회 논문집
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• pp.185-189
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• 2009

Recently, ultra high strength products can be manufactured by the hot press forming process of Boron steel in automotive and electronics industries. In order to get high strength, the hot press forming should be accompanied by quenching process inducing phase transformation. There are several types of the hot press forming processes according to the quenching method, water quenching and die quenching, etc. In the study, the process was numerically and physically simulated to compare the two types of quenching processes, and then the strength, hardness and dimensions of the products were compared with try-outs.

• 한국세라믹학회지
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• 제26권3호
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• pp.381-389
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• 1989

Effects of annealing temperature, time, and atmospehre on the flow characteristics of Atmospheric Pressure Chemical Vapor Deposition-borophosphosilicate glass were investigated. Stable step coverage can be obtained by annealing the BPSG film at 90$0^{\circ}C$ for 30 minutes in N2 atmosphere, but further heat treatment isnot effective. Flow characteristics of the BPSG film was better in steam atmosphere than in N2 atmosphere, and the factors which cause it were analyzed. The concentration of boron in the BPSG film was measured pretty accurately by FTIR spectrum. Boron content in the BPSG film was reduced by annealing treatment. The decrement of boron was greater in steam atmosphere than in the N2 atmosphere. Also it was found from the FTIR spectroscopic analysis that PH3 inhibited the oxidation of B2H6.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.493-496
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• 2008

The residual stress generated in the boron steel blank formed via hot press forming process was predicted by JMatPro, a material property modeler, and Abaqus. The numerical predictions were compared by the experimental measurements obtained by the instrumented indentation. Both the predicted and measured principal stresses monitored at the outer surface of central bending position were qualitatively in good agreement. It was concluded that the residual stresses generated from hot forming process is not negligible as it has been generally assumed, although the spring back deformation is quite small. This should be specially considered from the part design stage since the tensile nature of the residual stress exhibited on the surface may lead to the stress corrosion cracking.

• Journal of Electrochemical Science and Technology
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• 제14권3호
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• pp.215-221
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• 2023

A rapid and environment-friendly electrochemical sensor to determine the chemical oxygen demand (COD) has been developed. The boron-doped diamond (BDD) thin-film electrode is employed as the anode, which fully oxidizes organic pollutants and provides a current response in proportion to the COD values of the sample solution. The BDD-based amperometric COD sensor is optimized in terms of the applied potential and the solution pH. At the optimized conditions, the COD sensor exhibits a linear range of 0 to 80 mg/L and the detection limit of 1.1 mg/L. Using a set of model organic compounds, the electrochemical COD sensor is compared with the conventional dichromate COD method. The result shows an excellent correlation between the two methods.

• 분석과학
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• 제18권1호
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• pp.27-34
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• 2005

보론 동위원소 표준물을 이용하여 $Li_2B_4O_7$와 $Na_2B_4O_7$를 합성하고 이로부터 $Li_2BO_2{^+}$ (질량 56, 57)와 $Na_2BO_2{^+}$ (질량 88, 89)를 열 이온화 질량분석기를 이용하여 양이온 질량분석법(PTIMS)으로 측정하였으며 또한 같은 시료를 음이온 질량분석법 (NTIMS)으로 $^{10}BO_2{^-}$와 $^{11}BO_2{^-}$ (질량 42와 43)를 보론 (질량 10, 11)대신 측정하였다. 이들 방법 간의 정밀도와 정확도를 비교하고, 각각의 방법에서 동중원소 영향이 있는지를 알아보았다. 세 가지 방법 중에 NTIMS 방법이 제일 좋은 결과를 보여주었으며 작은 시료 양으로도 안정된 피크를 얻을 수 있었다. NTIMS 방법으로 지하수 약 $5{\mu}L$(약 8 ng-B)를 직접시료로 사용하여 보론 동위원소 비를 측정하여 상대 표준편차 0.03%의 결과를 얻었다. 또한 NTIMS-IDMS로 보론을 정량한 결과 $1.65{\pm}0.003{\mu}g-B/mL$을 얻었으며 ICP-AES 결과에 비해 좋은 정밀도를 보였다.