• Journal of the Korean Society for Heat Treatment
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• 제12권2호
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• pp.99-107
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• 1999

The graphitization is affected by the addition of small amount of the elements(such as Si, Al, Ni, B, Cr and Mn etc.) and the pre-treatment(such as cold rolling). Boron is well known element to accelerate the graphitization of cementite in high carbon steels. Also, cold rolling is known to accelerate the graphitization. But the graphitization nucleation mechanism by cold rolling is few reported. Therefore the effect of cold rolling in Fe-0.5%C-1.0%Si-0.47%Mn-0.005%B steel on the graphitization is investigated quantitatively using hardness test, optical microscope and scanning electron microscope, neutron induced microscopic radiography. The nucleation of graphite in cold-rolled Fe-0.5%C-1.0%Si-0.47%Mn-0.005%B steel is formed at void which is formed at pearlite/pearlite boundary by cold rolling. But the effect of cold rolling on graphitization in boron addition steel is more effective than that of no boron addition steel due to segregation of BN at void in boron addition steel.

• Korean Journal of Materials Research
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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.

• Journal of the Korean Society of Food Science and Nutrition
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• 제1권1호
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• pp.33-35
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• 1972

The curcumin method was adopted in this research for quantitative analysis of boron in plants. An experiment if this method is suitable to present conditions of our laboratory led us to the following conclusions. 1. In making ashes the addition of 0.5ml saturated $Ba(OH)_2$ solution to boron $1{\gamma}$. could completely prevent it from volatilizing. 2. The soft glass ware made in Korea was unfit for this experiment because of the differences in quality. The polyethylene cup was desirable for the quantitative analysis of boron.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.574-575
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• 2006

Due to the increasing use that the stainless steel is getting recently in the nuclear industry, this document proposes the study of the stainless steel 316L with boron addition. With the final product, the properties of the stainless steel 316L (good mechanical properties and high corrosion resistance) with the boron neutron absorption properties are claimed to unify. The P/M technologies allow adding higher boron quantities than with the solidification conventional technologies, where segregation is produced.

• Journal of Plant Biology
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• 제9권1_2호
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• pp.17-21
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• 1966

The mutual relationships of boron, Ca and sucrose were studied in relation to in vitro pollen growth and pollen bursting, by using conventient pollen from Crinum asiaticum for experiment. Crinum pollen are paticularly sensitive to Ca. Addition of very small amount of boron to cultural media was apparently synergistic to the action of sucrose and Ca in pollen germination and tube elongation. This action was extended to a higher level of boron concentraton. Combined application of boron, Ca and sucrose always gave the better results in pollen growth and protection against pollen bursting much more than when used singly. This indicated that there is a direct relationship between better growth of pollen and increased rigidity of pollen cell wall. A higher level of Ca concentration tended to increase bursting rate of pollen grains and decrease that of pollen tubes, while boron always depressed the rate of bursting. This was considered due to increased failure in pollen germination at high level of Ca that favors pollen tube elongation. The fact that Ca show an antagonistic effect on the suppressive action of high level of boron in pollen growth and shows different effect in response to pollen bursting from boron, suggested mode of Ca and boron action in the presence of sucrose is quiate different, although to increase in rigidity of pollen cell wall by them is in common nature. It was postulated therefore that Ca acts on pectins of pollen cell wall largely as "non-metabolic" and boron as "metabolic" promoter is pollen growth and protecting pollen bursting, since boron and Ca have common nature in strengthening the pollen cell wall but act differently.but act differently.

• Proceedings of the Korean Society For Composite Materials Conference
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• 한국복합재료학회 1999년도 추계학술발표대회 논문집
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• pp.198-203
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• 1999

2D carbon/carbon composites have been prepared with and without addition of 1, 3 and 5wt% of oxidation inhibitor boron and then heat teated up to 1700, 2000, 2300, 2600 each. This paper presents the effects of boron on the mechanical properties of 2D C/C composites in terms of the acceleration of graphitization and also discussed about the retardation of air oxidation.

• Journal of the Korean Ceramic Society
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• 제46권1호
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• pp.53-57
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• 2009

The h-BN powder was synthesized by amorphous $B_2O_3$ and activated carbon at $1550^{\circ}C$ in nitrogen atmosphere, whose properties were examined according to $MgB_6$ addition. Amount of $MgB_6$ addition was varied in the range of $0{\sim}$10\;wt% of the initial mixture. It was observed that $MgB_6$ addition led to an increase in the amount and the grain size of h-BN and decrease in the amount of $B_4C$ forming. When $MgB_6$ added 5 wt%, the amount and crystallinity of h-BN increased as the holding time at the synthesis temperature was prolonged. It was also confirmed that the regularity of three-dimensional ordering of h-BN increases.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.302-305
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• 2009

This paper examines the effect of nitride formation on formability for Cu bearing high strength extra low carbon (ELC) steel sheets. For this purpose, we have investigated the effect of addition of aluminium (Al) and boron (B) on texture and precipitation behavior of the ELC steel during continuous annealing. Mechanical properties and microstructures of the ELC steel sheets were analyzed as well using uni-axial tensile test, electron back-scattered diffraction (EBSD) technique and transmission electron microscopy (TEM) following pilot rolling and continuous annealing. It has been found that the addition of Al and B increases the precipitation of AlN and BN. What is more, the scavange of solute nitrogen is effective in increasing the formability of the ELC steels. In addition, the Al and B addition improves the aging property of the ELC steel.

• Journal of Korea Foundry Society
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• 제9권5호
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• pp.389-395
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• 1989

The effects of phosphorus and boron additions and isothermal holding time on the residual magnesium and sulfur content, and on the resultant graphite structure of cast irons were investigated. The effective recovery ratio of magnesium showed that adding phosphorus to the melt retarded the fading rate of magnesium but adding boron accelerated it. However, the residual sulfur content was found to be decreased with isothermal holding time at the begining, and then to be increased again with holding time by resulfurization. The Mg-Equivalent for producing compacted vermicular graphite structure was found to be increased with the addition of phosphorus, whereas to be decreased with the addition of boron.

• Membrane and Water Treatment
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• 제8권1호
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• pp.19-34
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• 2017

Boron exists in dilute concentrations in sea water, ground water and waste waters. Reactive liquid extraction can be used for removing boron to make the treated water suitable for drinking and irrigation, with its final concentration less than 0.5 ppm. The results of equilibrium experiments are reported on the removal of boron using 2-butyl-2-ethyl-1, 3-propanediol (BEPD as a nonionic carrier) in sunflower oil, a non-traditional solvent. The results of removal of boron from aqueous solutions in the concentration range 0.5-20 ppm are presented. It is shown that this new liquid membrane system, is able to remove boron from ground waters at their natural pH of 6-8 (without any chemical addition for pH adjustments). The removal efficiency is good when the process is upgraded to a hollow-fibre membrane contactor and approximately 45% boron can be removed in a single-stage contact. There are additional advantages of this new approach that includes reduced operational health and safety and environmental issues. The results reported here provide guidelines to the development of boron removal process using renewable, biodegradable, safe and cheap solvent system such as sunflower oil.