• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.269-269
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• 2012

수산화인회석(Hydroxyapatite)는 뼈와 이빨의 무기물 주성분으로서, 칼슘과 인산염으로 구성된다. 우리는 수산화인회석의 합성에 용융열 합성법(molten salt method), 수열 합성법(hydrothermal method), 용매열 합성법(solvothermal method)을 사용하였으며, pH 조절과 각기 다른 용매를 사용하여 다양한 형태의 수산화인회석을 합성하였다. TEM과 SEM을 이용하여 크기와 모양이 제어된 수산화인회석임을 확인할 수 있었다. 합성된 수산화인회석을 이용하여, 전이금속 Ruthenium cation을 Hydroxyapatite 표면에 ion-exchange 반응을 통하여 도입하였으며, ICP를 통하여 Ru 함양을 정량하였다. 합성된 Ruthenium Hydroxyapatite (Ru-HAP)를 이용하여 dimethylamine borane를 통한 수소 발생을 확인하였다.

• Safety and Health at Work
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• 제3권4호
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• pp.257-267
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• 2012

Occupational neurotoxic diseases have become increasingly common in Taiwan due to industrialization. Over the past 40 years, Taiwan has transformed from an agricultural society to an industrial society. The most common neurotoxic diseases also changed from organophosphate poisoning to heavy metal intoxication, and then to organic solvent and semiconductor agent poisoning. The nervous system is particularly vulnerable to toxic agents because of its high metabolic rate. Neurological manifestations may be transient or permanent, and may range from cognitive dysfunction, cerebellar ataxia, Parkinsonism, sensorimotor neuropathy and autonomic dysfunction to neuromuscular junction disorders. This study attempts to provide a review of the major outbreaks of occupational neurotoxins from 1968 to 2012. A total of 16 occupational neurotoxins, including organophosphates, toxic gases, heavy metals, organic solvents, and other toxic chemicals, were reviewed. Peer-reviewed articles related to the electrophysiology, neuroimaging, treatment and long-term follow up of these neurotoxic diseases were also obtained. The heavy metals involved consisted of lead, manganese, organic tin, mercury, arsenic, and thallium. The organic solvents included n-hexane, toluene, mixed solvents and carbon disulfide. Toxic gases such as carbon monoxide, and hydrogen sulfide were also included, along with toxic chemicals including polychlorinated biphenyls, tetramethylammonium hydroxide, organophosphates, and dimethylamine borane. In addition we attempted to correlate these events to the timeline of industrial development in Taiwan. By researching this topic, the hope is that it may help other developing countries to improve industrial hygiene and promote occupational safety and health care during the process of industrialization.

• Korean Chemical Engineering Research
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• 제56권6호
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• pp.895-900
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• 2018

본 연구에서는 Co-B, Co-W-B 합금 박막 형성을 위한 무전해 전착법을 고안하고, 이를 통해 형성한 합금 박막의 B과 W의 함량이 박막의 경도에 미치는 영향을 살펴보았다. 무전해 전착을 통해 무정형 상태의 Co 합금 박막을 성공적으로 형성할 수 있었으며, 환원제인 dimethylamine borane과 W의 원료인 sodium tungstate dihydrate의 농도를 조절함으로써 Co 합금 박막 내 혼합되는 B과 W의 함량을 조절하였다. 이를 통해 Co 합금 박막 내 전위(dislocation)의 전파(propagation)를 억제하는 B과 W의 함량이 증가할수록 박막의 경도가 증가함을 확인할 수 있었다. 뿐만 아니라, 무전해 전착 시 포기(aeration)를 수행하지 않을 경우에 포기를 수행한 경우보다 Co 합금 박막 내 B과 W의 함량을 대폭 증가시킬 수 있었고 최종적으로 Co-W-B 합금 박막의 경도를 8.9 (${\pm}0.3$) GPa까지 향상시켰다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2013년도 춘계학술대회 논문집
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• pp.137-137
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• 2013

본 연구에서는 반도체 검사 장비인 프로브 카드의 핵심 부품인 프로브 니들의 팁 부분의 내마모성을 향상시키기 위하여 무전해 Ni-B-W 합금 도금 실험을 실시하였다. 무전해 Ni-B-W 합금 도금 실험에서 여러 가지 제어인자 중 도금욕의 pH와 온도 그리고 환원제의 농도 등을 변수로 하였다. 도금욕 pH와 온도에 따른 전착속도 및 물성 변화를 관찰하였으며, 환원제 농도 변화에 의한 open circuit potential의 변화를 측정하였다.

• 한국재료학회지
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• 제6권10호
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• pp.1007-1016
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• 1996

무전해도금법에 의한 퍼멀로이 박막의 도금 최적조건 규명 및 자기적 특성 향상을 위하여 퍼멀로이 박막의 미세구조 및 자기적 특성 등을 연구하였다. 소지는 알루미나를 사용하였으며, 환원제는 boron을 포함하는 Ni-Fe-B도금막이 형성되는 DMAB(dimethylamine borane)를 사용하였다. 도금시 인가된 도금막이 무자장하에서 도금된 도금막과 비교하여 기공이 적고, 조밀한 막이 형성됨을 SEM을 통하여 확인하였다. 도금속도는 온도, pH, DMAB 농도가 증가할수록 증가하였다. 도금막에 함유되는 boron의 함량은 pH가 감소할수록, 온도와 DMAB농도가 증가할수록 증가하였다. 도금막 보자력값은 30$0^{\circ}C$에서 1시간 열처리하였을 때 약 4.5Oe로 감소하였고, 포화자기유도값은 3-5kG 정도 증가하였다. 이때 포화자기유도값은 자장하에서 도금된 후 열처리한 도금막이 무자장하에서 도금된 후 열처리한 도금막에 비하여 1.7kG 정도 높았다. 또한 열처리 후의 도금막이 열처리 전의 도금막에 비하여 기공이 적고 조밀한 도금막을 형성함을 볼 수 있었다.

• 한국표면공학회지
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• 제32권2호
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• pp.172-181
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• 1999

The effect of the DMAB concentration, temperature, deposition time, and stabilizer concentration on the precipitation reaction of the electroless nickel plating using dimethylamine borane (DMAB) as reducing agent was investigated to by the weight gain and electrochemical method. The deposition rate was dependent with DMAB concentration. The polarization resistance of the precipitation reaction was reduced with DMAB concentration. The precipitation reaction rate of Ni-B deposits was controlled by the oxidation rate of DMAB as the source of electron. The boron content of the deposit was constant at about 5.5wt%, even when DMAB concentration in the solution was increased. The effect of temperature and stabilizer ($Pb(NO_3)_2$) concentration on deposition rate was shown to have co-dependent behaviors.

• 한국재료학회지
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• 제24권11호
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• pp.632-638
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• 2014

We investigated the effects of DMAB (Borane dimethylamine complex, C2H10BN) in electroless Ni-B film with addition of DMAB as reducing agent for electroless Ni plating. The electroless Ni-B films were formed by electroless plating of near neutral pH (pH 6.5 and pH 7) at $50^{\circ}C$. The electroless plated Ni-B films were coated on screen printed Ag pattern/PET (polyethylene terephthalate). According to the increase of DMAB (from 0 to 1 mole), the deposition rate and the grain size of electroless Ni-B film increased and the boron (B) content also increased. In crystallinity of electroless Ni-B films, an amorphization reaction was enhanced in the formation of Ni-B film with an increasing content of DMAB; the Ni-B film with < 1 B at.% had a weak fcc structure with a nano crystalline size, and the Ni-B films with > 5 B at.% had an amorphous structure. In addition, the Ni-B film was selectively grown on the printed Ag paste layer without damage to the PET surface. From this result, we concluded that formation of electroless Ni-B film is possible by a neutral process (~green process) at a low temperature of $50^{\circ}C$.

• 한국표면공학회지
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• 제45권3호
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• pp.97-105
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• 2012

The effects of pH, types of applied current, agitation method and time, additive on the amount of co-deposited $TiO_2$ particles in the matrix were investigated. The deposition rates increased with increasing pH values, while the volume fraction of $TiO_2$ particles and the size of agglomerated $TiO_2$ particles in the composite decreased. The volume fraction of $TiO_2$ particles in the composite decreased when pulsed current of 50% duty cycle was used. And the size of agglomerated $TiO_2$ particles in the nickel matrix of pulsed current was smaller than that of DC current specimen. The volume fraction of $TiO_2$ particles in the matrix decreased with longer time by air agitation, but in case of using magnetic bar, volume fraction in the same range of time was relatively constant. The volume fraction of the electrodeposited Ni-$TiO_2$ composite in the solution containing 0.01 M Dimethylamine borane (DMAB) increased slightly with increasing agitation time regardless of agitation methods. Thermal stability of the electrodeposited Ni-$TiO_2$ composite increased with lower pH at the temperature range of $200{\sim}800^{\circ}C$, and the results showed that the amount of co-deposited $TiO_2$ relies more on the deposition rate than zetapotential of $TiO_2$ particles.