• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2016년도 추계학술대회 논문집
• /
• pp.124.2-124.2
• /
• 2016

Corrosion resistance and adhesion of electro-paint (E-paint) with fluoride conversion coating (FCC) on AZ31 Mg alloy were studied. Corrosion resistance and adhesion were studied as a function of FCC-treatment time and concentration of FCC-bath. Aqueous hydrogen fluoride (HF) solutions, with concentrations ranging from 0.5 M to 5 M, were used to form FCC on chemically polished AZ31 Mg alloy samples for six different times; 10, 30, 60, 90, 120, and 180s. The results from salt spray test (SST) showed that corrosion resistance of E-paint appeared to decrease with increasing FCC treatment times in low concentration FCC baths. The number of blisters formed on the FCC-treated samples increased with increasing FCC treatment time of more than 1 min in low concentration (0.5 M to 1 M) solutions. On the other hand, samples treated in the 5 M HF solution for 120s showed no delamination or blistering even after 1200h of SST.

• Child Health Nursing Research
• /
• 제26권1호
• /
• pp.72-81
• /
• 2020

Purpose: This study was conducted to investigate nurses' perceptions and performance of family-centered care (FCC) at a children's hospital in Sri Lanka and to explore the feasibility of implementing FCC in the context of the Sri Lankan healthcare system. Methods: A convergent, parallel, mixed-methods design was applied to understand Sri Lankan nurses' perspectives on FCC. In total, 157 nurses working at a large teritagy children's hospital responded to a self-report survey and 18 nurses participated in focus group interviews. Results: Of the factors of FCC, family participation in caring for children received the highest score (4.09±0.51) for perceptions, and information-sharing received the highest score (3.54±0.55) for performance. The qualitative data revealed the following five themes: (a) importance of the family in caring for children; (b) helping families during children's hospitalization; (c) taking steps to implement FCC, even with imperfect knowledge; (d) barriers in the current situation; and (e) suggested strategies to promote FCC. Conclusion: Participants endorsed the concept of FCC and demonstrated some aspects of it in their day-to-day practice. The results indicate a clear knowledge deficit and several challenges, which need to be addressed to effectively implement FCC.

• Bulletin of the Korean Chemical Society
• /
• 제33권8호
• /
• pp.2642-2646
• /
• 2012

Pretreatment of spent FCC catalyst and its application in remove trace olefins in aromatics were investigated in this research. The most effective pretreatment route of spent FCC catalyst was calcining at $700^{\circ}C$ for 1 h, washing with 5% oxalic acid solution in ultrasonic reactor and dried. Treated spent FCC catalyst was modified with metal halides, then to prepare catalyst to remove trace olefins in aromatics. X-ray diffraction, Pyridine-FTIR, $N_2$ adsorption-desorption and inductively coupled plasma optical emission spectrometer (ICP-OES) were used to investigate the pretreatment process. The result showed that the performance of the treated spent FCC catalyst was much greater than that of the spent FCC catalyst, which indicted the possibility and improvement of this research.

• Applied Microscopy
• /
• 제45권1호
• /
• pp.9-15
• /
• 2015

In the present study, microstructural evolution in CuCrFeNi, CuCrFeNiMn, and CuCrFeNiMnAl alloys has been investigated. The as-cast CuCrFeNi alloy consists of a single fcc phase with the lattice parameter of 0.358 nm, while the as-cast CuCrFeNiMn alloy consists of (bcc+fcc1+fcc2) phases with lattice parameters of 0.287 nm, 0.366 nm, and 0.361 nm. The heat treatment of the cast CuCrFeNiMn alloy results in the different type of microstructure depending on the heat treatment temperature. At $900^{\circ}C$ a new thermodynamically stable phase appears instead of the bcc solid solution phase, while at $1,000^{\circ}C$, the heat treated microstructure is almost same as that in the as-cast state. The addition of Al in CuCrFeNiMn alloy changes the constituent phases from (fcc1+fcc2+bcc) to (bcc1+bcc2).

• 한국표면공학회지
• /
• 제53권1호
• /
• pp.1-8
• /
• 2020

Sulfamate-chloride baths were fabricated to study the properties of the electrodeposited Ni and NiCo thin films. The dependences of current efficiency, deposit composition of Ni and Co, residual stress, surface morphology and microstructure of electrodeposited Ni and NiCo thin films on CoCl₂ concentration in sulfamate-chloride baths were investigated. The current efficiency was measured to be more than about 90%, independent of the changes of CoCl₂ concentration in the baths. Residual stress of Ni and NiCo thin films was increased from about 45 to about 250 MPa with varying CoCl₂ concentration from 0 to 0.210 M CoCl₂ in the baths and then reached to a plateau, about 250 MPa above 0.420 M CoCl₂ concentration. Nodular surface morphologies were observed at most CoCl₂ concentrations in the baths except 0.210 M. NiCo thin film electrodeposited from the bath with 0.210 M CoCl₂ concentration showed an acicular surface morphology. Pure Ni thin film consists of FCC(111), FCC(200), FCC(220), and FCC(311) peaks without any preferred orientation. On the other hand NiCo thin films make up of HCP(100), FCC(111), HCP(101), FCC(200), FCC(220) or HCP(110), FCC(311) or HCP(112) and FCC(222) peaks. It was revealed from the analysis of XRD result that FCC(111) peak at the NiCo thin film electrodeposited from the bath with 0.084 M CoCl₂ concentration can be regarded as the preferred orientation. However the peak of the preferred orientation was changed to FCC(220) or HCP(110) above 0.084 M CoCl₂ concentration in the baths. Then the intensity of FCC(220) or HCP(110) peak was gradually decreased with increasing CoCl₂ concentration further. The crystalline size of pure Ni thin film was observed to be about 53 ㎛ and those of NiCo thin films were in the range of 35~45 ㎛.

• 한국동물위생학회지
• /
• 제16권1호
• /
• pp.1-10
• /
• 1993

Samples of bulk herd milk, foremilk, last milk (stripping) and individual cow sample were collected and their somatic cell number were counted with Fossomatic counter (FCC), Coulter counter(CC), direct microscopic somatic cell count(DMSCC) and Califormia mastitis test (CMT), The results were compared and summarized as follows : 1. Mean somatic cell counts of 120 bulk herd milk samples obtained by DMSCC, FCC and CC were 433,203, 481,213 and 676,245 respectively. 2. Mean somatic cell counts of 116 foremilk samples obtained by DMSCC, FCC and CC were 515,035, 611,845 and 725,051 respectively 3. Mean somatic cell counts of 87 last milk samples obtained by DMSCC, FCC and CC were 718,506, 839,874 and 1,041,160 respectively. 4. Mean somatic cell counts of 57 individual cow samples obtained by DMSCC, FCC and CC were 449,258, 491,018 and 521,315 respectively. 5. Mean somatic cell counts of all samples increased with the increasing CMT score, and the cell counts were higher by CC than by FCC. 6. The correlation coefficients between the somatic cell counts by CMT and CC were 0.926 in bulk herd milk, 0.707 in foremilk 0.688 in last milk and 0.675 in individual cow sample, respectively 7. The correlation coefficients between the somatic cell counts by CMT and FCC were 0. 945 in bulk herd milk, 0.705 in foremilk 0.694 in last milk and 0.727 in individual cow sample, respectively. 8. The correlation coefficients between the somatic cell counts by CC and FCC were 0.978 in bulk herd milk, 0.997 in foremilk 0.983 in last milk and 0.985 in individual cow sample, respectively.

• 한국전자파학회지:전자파기술
• /
• 제7권1호
• /
• pp.4-13
• /
• 1996

미국 연방통신위원회(FCC)에서는 1996. 5. 14일 부로 Digital Device에 대한 인증제도를 자기입증방식(DoC)으로 변경한다는 방침을 확정, 발표하였다(FCC 96-206, ET Docket No. 95-19, Report and Order). 이 새로운 자기입증제도는 기존 FCC의 타율규제방식(Certification, Verification, Notification등) 을 탈피하여 제조자 자율에 의한 인증개념을 도입한 것으로서, 어떤 제품(Digital Device에 대해서 FCC가 정한 기술기준에 의거 시험하여 합격하였을 경우, 제조자(인증권자) 스스로 적합선언서 (DoC : Declaration of Conformity)를 채택하고 해당 제품에 인증마크를 부착하여 출하시킨다는 것으로 기존 EU의 CE-Mark 인증제도 중 Module A와 유사한 제도이다. FCC는 이와 같은 제도변경을 위해서 1995년 2월에 이미 기본방침을 발표하여 그동안 관련업계 의 광범위한 의견수렴을 거쳤으며, 필요한 법적보완사항을 위해서 일부 통신법을 개정, 완료하였 고(1996 통신법 403(f), 상무성, NIST 등 관계기관과의 의견조정을 마친 후 본 시행안을 확정, 공표 하였다.

• 한국표면공학회지
• /
• 제51권1호
• /
• pp.62-70
• /
• 2018

Sulfamate plating solution containing a small amount of chloride bath was fabricated to study the properties of the electrodeposited Ni thin films. Effects of the changes of current density and additive concentration on current efficiency, residual stress, surface morphology and microstructure of Ni thin films electrodeposited from Ni sulfamate-chloride baths were investigated. The current efficiency was measured to be more than about 95%, independent of the changes of current density and saccharin concentration in the baths. Residual stress of Ni thin film was appeared to be the compressive stress modes in the range of $5{\sim}30mA/cm^2$ current density. Maximum compressive stress was observed at the current density of $10mA/cm^2$. Compressive stress values of Ni thin/thick films were increased to be about -85~-100 MPa with increasing saccharin concentration from 0 to 0.0195 M(4 g/L). Surface morphology was changed from smooth to nodule surface appearance with increasing the current density. Smooth surface morphology of Ni thin films electrodeposited from the baths containing saccharin was observed, independent of the saccharin concentration. Ni thin/thick films consist of FCC(111), FCC(200), FCC(220), FCC(311) and FCC(222) peaks. It was revealed that the FCC(200) peak of Ni thin films is the preferred orientation in the range of $5{\sim}30mA/cm^2$ current density. The intensity of FCC(200) peak was gradually decreased and the intensity of FCC(111) peak was increased with increasing saccharin concentration in the baths.

• 한국자기학회지
• /
• 제19권5호
• /
• pp.165-170
• /
• 2009

준안정 상태인 덩치 fcc Fe는 반강자성 상태가 기저 상태인 것으로 알려져 있고 적절한 fcc 금속 표면 위에 fcc Fe를 성장시킬 수 있음이 보고된 바 있다. 본 연구에서는 fcc 금속 (001) 표면 위의 Fe 원자층의 자성을 연구하기 위해 Cu(001), Rh(001), Pd(001), Ag(001) 표면 위의 Fe 단층의 자성을 제일원리계산 방법 중 자성 연구에 가장 적합한 총퍼텐셜선형보강평면파(fullpotential linearized augmented plane wave; FLAPW) 방법을 사용하여 연구하였다. 고려한 계 중에서 2차원 격자상수가 가장 작은 Cu(001) 표면과 가장 큰 Ag(001) 표면 위의 Fe 단층은 강자성이 비교적 큰 에너지 차이로 Fe-fcc 금속 층간 거리에 관계없이 안정적이었고, 중간 크기의 2차원 격자상수를 가진 Rh(001)과 Pd(001) 표면 위의 Fe 단층은 반강자성 상태가 안정적이었으나, 층간 거리가 커짐에 따라 강자성 상태가 안정적일 수도 있는 것으로 계산되었다. 계산된 자기모멘트는 1Fe/Cu(001), 1Fe/Rh(001), 1Fe/Pd(001), 1Fe/Ag(001)의 강자성 상태에서 2.811, 2.945, 2.987, 2.990 $_{{\mu}B}$이었고, 반강자성 상태에서는 2.624, 2.879, 2.922, 3.001 $_{{\mu}B}$이었다.

• 공업화학
• /
• 제8권4호
• /
• pp.679-684
• /
• 1997

석유화학공업에서 사용된 유동접촉분해(FCC) 폐촉매의 주성분은 Si와 Al이며, 그외에 Fe, Zn, Ti 등의 기본금속과 알칼리금속 및 Ce, Nd, Ni, V 등의 희유금속이 함유되어 있다. $0.25mo1/dm^3-H_2SO_4$를 침출제로 폐촉매를 침출하였을 때 Ce가 640, Nd가 310, 그리고 V가 $450mg/dm^3$ 함유된 pH 1.0의 침출액을 얻었고, 아미노인산형 킬레이트수지에 의하여 Ce와 Nd를 선택흡착시킨 후, $4.0mol/dm^3-HCl$로 용리시켜 $1.2g/dm^3$의 Ce와 $0.75 g/dm^3$의 Nd 농축액을 얻었다. 농축액을 다시 옥살산 침전 및 공기산화법으로 처리하여 Ce와 Nd의 분리가 가능하였으며, 염소이온 공존하에 추출제 TOPO를 이용한 용매추출법으로 V와 Al을 각각 분리시켜, FCC 폐촉매로부터 순도가 99%인 Ce, Nd 및 V의 분리정제가 가능하였다.