• Fibers and Polymers
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• 제2권4호
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• pp.190-195
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• 2001

Additives, such as sodium perborate and borax, were examined in dialdehyde wrinkle resistant finishing of cotton. Results indicated that the whiteness index(WI) of cotton treated with dialdehyde and additive showed about 90% of WI of the untreated cotton but with decrease in wrinkle recovery angle (WRA) due to inhibition effect of these additives. Effect of additive on the WRA reduction was more prominent with glutaraldehyde than with glyoxal. Reduction in WRA of cotton treated with both dialdehydes and boron compound was minimized by simultaneous addition of formic acid in the bath. Addition of formic acid was also generally beneficial in maintaining WI retentions after 8 months storage. Furthermore, boron compounds were also effective in improving retentions of mechanical properties. By FTIR analysis the residual aldehyde group was detected on the dialdehyde-finished cotton, whereas no peak was shown by addition of boron compounds. This suggested that the residual aldehyde group was a main cause of fabric yellowing on the dialdehyde-finished cotton. Dialhehyde with boron compound, therefore, can be used to replace a conventional formaldehyde-containing wrinkle resistant finishing of cotton.

• 열처리공학회지
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• 제12권2호
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• pp.136-144
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• 1999

The study on the wear characteristics of compound layers formed during gaseous nitrocarburising in the medium carbon boron steels and the plain carbon steel has been carried out by using a pin-on-disc type wear test machine under the oil lubricating condition at room temperature and by varying applied loads, sliding speeds and wear distances. Values of friction coefficient measured at the sliding speed of 0.4m/sec under the oil lubricating condition have been shown to decrease considerably with increasing applied load and become gradually a constant value as load is increased to a higher value, showing that the transition load for friction coefficient appears at an applied load of 247.2N. The length and volume wear rates of compound layer have been revealed to relatively constantly increase, also showing that the wear life per unit thickness of compound layer turns out to be superior as porous layer has a denser and thinner appearance. As the sliding speed increases during wear test performed by varying sliding speed at a load of 63.2N under the oil lubricating condition for medium carbon boron steel nitrocarburised in gas atmosphere, the wear rate has been found to increase, the friction coefficient to decrease and the wear life per unit thickness of compound layer to decrease considerably.

• Journal of Photoscience
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• 제3권1호
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• pp.39-42
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• 1996

The photochemical reaction of phenyl(tribromomethyl)mercury with nido-decaborane gives a new boron cluster expanded compound. The two borons at the 6- and 9- positions in decaborane behave as electrophilic centers for the reaction with dibromocarbene. The first step in this reaction is the addition of two molar equivalents of dibromocarbene which is produced from phenyl(tribromomethyl)mercury to nido-decaborane. In the second step the unstable intermediate generates the product, 1,2-$Br_2C_2B_{10}H_{10}$ through loss of H$_2$.

• Nuclear Engineering and Technology
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• 제55권7호
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• pp.2419-2431
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• 2023

Experiments related to Boron Neutron Capture Therapy (BNCT) accomplished at the Institute of Nuclear Techniques (INT), Budapest University of Technology and Economics (TUB) are presented. Relevant investigations are required before designing BNCT for vivo applications. Samples of relevant boron compounds (H₃BO₃, BDTPA) usually employed in BNCT were investigated with neutron beam. Channel #5 in the research reactor (100 kW) of INT-TUB provides the neutron beam. Boron samples are mounted on a carrier for neutron irradiation. The particle attenuation of several carrier materials was investigated, and the one with the lowest attenuation was selected. The effects of boron compound type, mass, and compound phase state were also investigated. To detect the emitted charged particles, a traditional ZnS(Ag) detector was employed. The neutron beam's interaction with the detector-detecting layer is investigated. Graphite (as a moderator) was employed to change the neutron beam's characteristics. The fast neutron beam was also thermalized by placing a portable fast neutron source in a paraffin container and irradiating the H₃BO₃. The obtained results suggest that the direct measurement approach appears to be insufficiently sensitive for determining the radiation dose committed by the Alpha particles from the ¹⁰B (n,α) reaction. As a result, a new approach must be used.

• 한국토양비료학회지
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• 제16권3호
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• pp.250-255
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• 1983

밤나무에 대(對)한 합리적(合理的)인 시비(施肥)를 목적(目的)으로 밤나무 전용복비(專用複肥)를 관발(關發)하여 1981-1982년(年)에 걸쳐 은기품종(銀寄品種)을 공시(供試)하여 여비시험(旅肥試驗)을 한 결과(結果)는 다음과 같다. 1. 밤나무의 생장량(生長量)은 함붕소복비구(含硼素複肥區)에서 대체(大體)로 양호(良好)하였다. 2. 함붕소구(含硼素區)에서는 낙과방지효과(落果防止效果)가 커서 성숙구(成熟毬) 과수(果數)가 현저(顯著)하게 많았다. 3. 밤수량(收量)은 1982년도(年度) 경우 함붕소복비구(含硼素複肥區)에서 매우 높아 일반복비구(一般複肥區)에 비(比)해 6배(倍)나 되었다. 4. 함붕소복비시용(含硼素複肥施用)으로 토양(土壤) 및 식물체중(植物體中)의 붕소함량(硼素含量)이 높았으며 이는 밤나무의 생장촉진(生長促進), 낙과방지(落果防止)에 영향을 주어 밤 증수(增收)에 기여 하였다고 판단(判斷)된다. 5. 밤의 획기적증수(劃期的增收)를 기(期)하기 위(爲)하여는 밤나무 전용복비(專用複肥)의 시용(施用)은 불가피(不可避)한 것으로 생각된다.

• 대한방사성의약품학회지
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• 제6권1호
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• pp.10-19
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• 2020

Boron Neutron Capture Therapy (BNCT) has the advantage of selectively removing cancer cells ingesting boron compounds. In this study, the benefits for treatment time and boron compound injection dose were compared between current neutron sources and a high current neutron sources to be developed in near future. The time-activity curve (TAC) of GBM (Glioblastoma) for one bolus injection was obtained by applying modified 3 compartment model. The treatment time was determined for an accelerator-based neutron sources at the present time and a high current accelerator based neutron source to be developed in the near future. In the case of the double amount of IAEA-recommended neutron flux, the treatment time was shortened to 15 minutes. In the case of high current accelerators, which are five times the amount of IAEA-recommended neutron flux, the irradiation time is within 5 minutes. The use of a high current accelerator based neutron source in BNCT is advantageous in terms of treatment time. In addition, it can increase the efficiency of use of neutrons and reduce the boron compound injection dose to patients, thus reducing pharmacological toxicity.

• 대한방사성의약품학회지
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• 제8권1호
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• pp.17-23
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• 2022

Boron neutron capture therapy is a precision treatment technology that selectively destroys only tumor cells by irradiating thermal neutrons after accumulating boron drugs in tumor cells. Brain tumor is difficult to diagnose and treat due to the low permeability and targeting of drugs caused by the blood-brain-barrier. Crossing the BBB is essential for drug delivery to the brain. In this study, we designed and synthesized a novel compound incorporating benzothiazole to develop a boron drug with high BBB permeability and selectivity for brain tumor cells. In addition, their potential as a BNCT drugs was evaluated.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.15-15
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• 2011

As you know, boron compounds, borax ($Na_2B_4O_5(OH)_4{\cdot}8H_2O$) etc. were known thousands of years ago. As for natural boron, it has two naturally occurring and stable isotopes, boron 11 ($^{11}B$) and boron 10 ($^{10}B$). The neutron absorption $^{10}B$ is included about 19~20% with 80~81% $^{11}B$. Boron is similar to carbon in its capability to form stable covalently bonded molecular networks. The mass difference results in a wide range of ${\beta}$ values between the $^{11}B$ and $^{10}B$. The $^{10}B$ isotope, stable with 5 neutrons is excellent at capturing thermal neutrons. For example, it is possible to decrease a thermal neutron required for the nuclear reaction of uranium 235 ($^{235}U$). If $^{10}B$ absorbs a neutron ($^1n$), it will change to $^7Li+^1{\alpha}$ (${\alpha}$ ray, like $^4He$) with prompt ${\gamma}$ ray from $^{11}B$ $^{11}B$ (equation 1). $$^{10}B+^1n\;{\rightarrow}\;^{11}B\;{\rightarrow}\; prompt \;{\gamma}\;ray (478 keV), \;^7Li+4{\alpha}\;(4He)\;\;\;\;{\cdots}\; (1)$$ If about 1% boron is added to stainless steel, it is known that a neutron shielding effect will be 3 times the boron free steel. Enriched boron or $^{10}B$ is used in both radiation shielding and in boron neutron capture therapy. Then, $^{10}B$ is used for reactivity control and in emergency shutdown systems in nuclear reactors. Furthermore, boron carbide, $B_4C$, is used as the charge of a nuclear fission reaction control rod material and neutron cover material for nuclear reactors. The $B_4C$ powder of natural B composition is used as a charge of a control material of a boiling water reactor (BWR) which occupies commercial power reactors in nuclear power generation. The $B_4C$ sintered body which adjusted $^{10}B$ concentration is used as a charge of a control material of the fast breeder reactor (FBR) currently developed aiming at establishment of a nuclear fuel cycle. In this study for new boron compound, silicon boride ceramics for capturing thermal neutrons, preparation and characterization of both silicon tetraboride ($SiB_4$) and silicon hexaboride ($SiB_6$) and ceramics produced by sintering were investigated in order to determine the suitability of this material for nuclear power generation. The relative density increased with increasing sintering temperature. With a sintering temperature of 1,923 K, a sintered body having a relative density of more than 99% was obtained. The Vickers hardness increased with increasing sintering temperature. The best result was a Vickers hardness of 28 GPa for the $SiB_6$ sintered at 1,923K for 1 h. The high temperature Vickers hardness of the $SiB_6$ sintered body changed from 28 to 12 GPa in the temperature range of room temperature to 1,273 K. The thermal conductivity of the SiB6 sintered body changed from 9.1 to 2.4 W/mK in the range of room temperature to 1,273 K.

• 한국화재소방학회논문지
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• 제32권3호
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• pp.19-26
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• 2018

붕산과 5붕산암모늄으로 처리한 편백목재 시험편의 연소특성에 관한 실험을 ISO 5660-1 표준에 따른 콘칼로리미터를 이용하여 수행하였다. 그 결과 붕소화합물로 처리한 시험편의 화재성능지수(FPI)는 공시편보다 1.2~2.1배 증가하였고, 화재성장지수(FGI)는 공시편보다 1.6~8.4% 증가하였다. 또한 총연기발생률(TSR)은 공시편보다 9.0~28.3.% 낮았다. 이것은 붕소화합물로 처리한 시험편이 난연효과로 탄화층을 생성하기 때문으로 이해된다. 공시편은 418 s에서 가장 높은 CO농도인 0.01112%를 보였으나 붕소화합물로 처리한 시험편은 공시편보다 13.2~37.5% 감소하였다. 따라서 붕소화합물로 처리한 목재는 화재위험성과 위해성이 낮아질 것으로 예상된다.

• 한국대기환경학회지
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• 제26권6호
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• pp.649-656
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• 2010

Boron-doped $TiO_2$ photocatalysts were synthesized by a modified sol-gel method and their photocatalytic activities were performed and compared with those of pure synthetic and commercial $TiO_2$ catalysts under UV or visible light conditions. Pure $TiO_2$ itself exhibited very negligible photocatalytic performance under visible light conditions in the aspects of toluene decomposition reactions, although significant decomposition potential was observed as expected with UV light conditions. However, boron doping over $TiO_2$ significantly improved photocatalytic activity particularly under visible conditions, where over 95% degradation of toluene was achieved with 1wt% $B-TiO_2$ within 2 hrs. All the decomposition reactions seemed to follow pseudo first-order kinetics. The effects of boron-doping and its characteristics are further discussed through the kinetic studies and comparison of results.