In this paper we developed the Teflon heater which contains a built in temperature sensor and a relay for improved plating equipment system. Teflon heater is improved by using Pt 100Ω sensor which can detect until 600°C. When the bath temperature sensor detects over 60°C or the Teflon heater sensor detects over 240°C they temporarily shut down the heater to control temperature. Also relay completely shuts down main power when detects instant temperature is detected over 5% of 240°C by the heater sensor to prevent teflon melting down and fire spreads. Developed plating equipment system can monitor a real time temperature in the teflon tube and bath water. Therefore we think the proposed plating equipment can eliminate the possibility of fire in plating processes fundamentally.

본 연구에서는 경기도 안산 도금폐수 처리시설에서 총 4 개 시료를 대상으로 국내 생태독성시험 표준 생물 종인 D. magna와 국내서식 종 E. agilis를 이용한 생태독성을 수행 하였다. 시료에 대한 독성원인물질 탐색은 D. magna 급성 독성시험법을 이용하여 1) 시료 내 개별 중금속 농도와 시 료의 독성영향과의 상관분석, 2) 원인물질탐색 실험 (단계적 pH, SS, 중금속, 산화제 Test), 3) 중금속 목적물질에 대한 독 성영향 농도와 시료 내 목적물질의 농도와의 비교 등을 통 해 평가하였다. 도금폐수 시료에 대한 E. agilis 시험법의 적 용 가능성 평가는 E. agilis 실시간 생태독성 모니터링장비 (E-Tox 시스템)를 이용하여 수행하였다. D. magna 시험 결 과, 시료의 독성원인물질군은 부유물질 (SS), 산화제 그리고 중금속으로 예측되었으며 개별 중금속 원인물질은 Cu, Hg, Ag로 판단되었다. E. agilis는 D. magna에 비해 독성 민감도 는 높지 않으나 D. magna에 독성영향을 나타내는 도금폐수 시료에 신속하고 민감하게 반응하였다. 본 연구의 결과 D. magna를 이용한 단계별 독성원인물질 탐색평가과정은 생 태독성기준을 초과하는 도금폐수 시료에 대한 독성 원인물 질을 파악하는데 효과적으로 나타났다. 또한 E-agilis 시험은 향후 도금폐수의 수질을 실시간으로 모니터링 하는데 적용 가능 할 것으로 판단된다.

The metal plating industry produces a large amount of wastewater generally containing heavy metals with various chemical compounds; as such, treating the wastewater is both an environmental and an economic challenge. A vacuum evaporation system has been developed to effectively reduce the volume of plating wastewater. However, the gas stream discharged from the distillation unit of the evaporator is often contaminated with high concentrations of odorous compounds such as ammonia and dimethyl disulfide (DMDS). In this study, a non-thermal plasma process operated in wet conditions was applied to remove the odorous compounds, and it showed high removal efficiencies of greater than 99% for ammonia and 95% for DMDS. However, the gas flowrate more substantially affected the efficiency of ammonia removal than the efficiency of DMDS removal, because the higher the gas flowrate, the shorter the contact time between the odorous compound and the mist particles in the wet plasma reactor. The analyses of the maximum removal capacity indicated that the wet non-thermal plasma system was effective for treating the odorous compounds at a loading rate of less than 20 mg/m3/min even though the lowest amount of electrical power was applied. Therefore, the wet-type non-thermal plasma system is expected alleviate to effectively abate the odor problem of the vacuum evaporator used in the treatment of plating wastewater.

This study was performed to evaluate the alternative improvement plans for removal efficiency of plating wastewater treatment processes with high concentrations of heavy metals and total nitrogen in the influent. The average removal efficiency rates of the existing wastewater treatment plant were 58% of CODcr, 74% of CODmn, 78% of TN, 99% of TP, respectively. However, the concentration of SS (about 250 mg/L) was over the emission standard (120 mg/L). TN and Cu2+ concentrations were over the emission standard; about 62 mg/L and 5.2 mg/L, respectively. Carbon source quantity, fed into the anoxic tank of the biological wastewater treatment process, was controled by calculating the optimum required COD amount for denitrification. The removal efficiency rates of Zn2+, Cu2+, and Ni2+ were achieved using an electrolysis reactor 89%, 89%, and 99%, respectively. Therefore, it was recommended to modify the existing wastewater treatment process including the chemical precipitation to the electrolysis reactor as an efficient and environmentally effective alternative.

A number of plating companies have been exposed to the risk of fire due to unexpected temperature increasing of water in a plating bath. Since the companies are not able to forecast the unexpected temperature increasing of water and most of raw materials in the plating process have low ignition temperature, it is easy to be exposed to the risk of fire. Thus, the companies have to notice the changes immediately to prevent the risk of fire from plating process. Due to this reason, an agile and systematic temperature monitoring system is required for the plating companies. Unfortunately, in case of small size companies, it is hard to purchase a systematic solution and be offered consulting from one of the risk management consulting companies due to an expensive cost. In addition, most of the companies have insufficient research and development (R&D) experts to autonomously develop the risk management solution. In this article, we developed a real time remote temperature monitoring system which is easy to operate with a lower cost. The system is constructed by using Raspberry Pi single board computer and Android application to release an economic issue for the small sized plating manufacturing companies. The derived system is able to monitor the temperature continuously with tracking the temperature in the batch in a short time and transmit a push-alarm to a target-device located in a remoted area when the temperature exceeds a certain hazardous-temperature level. Therefore, the target small plating company achieves a risk management system with a small cost.

Cu circuits were successfully fabricated on flexible PET(polyethylene terephthalate) substrates using wettability difference and electroless plating without an etching process. The wettability of Cu plating solution on PET was controlled by oxygen plasma treatment and SiOx-DLC(silicon oxide containing diamond like carbon) coating by HMDSO(hexamethyldisiloxane) plasma. With an increase of the height of the nanostructures on the PET surface with the oxygen plasma treatment time, the wettability difference between the hydrophilicity and hydrophobicity increased, which allowed the etchless formation of a Cu pattern with high peel strength by selective Cu plating. When the height of the nanostructure was more than 1400 nm (60 min oxygen plasma treatment), the reduction of the critical impalement pressure with the decreasing density of the nanostructure caused the precipitation of copper in the hydrophobic region.

The monolayer engineering diamond particles are aligned on the oxygen free Cu plates with electroless Ni plating layer. The mean diamond particle sizes of 15, 23 and 50 μm are used as thermal conductivity pathway for fabricating metal/carbon multi-layer composite material systems. Interconnected void structure of irregular shaped diamond particles allow dense electroless Ni plating layer on Cu plate and fixing them with 37-43% Ni thickness of their mean diameter. The thermal conductivity decrease with increasing measurement temperature up to 150oC in all diamond size conditions. When the diamond particle size is increased from 15 μm to 50 μm (Max. 304 W/mK at room temperature) tended to increase thermal conductivity, because the volume fraction of diamond is increased inside plating layer.

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˚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˚C.

We compared between an automated most-probable-number technique TEMPO®TVC and traditional plating methods PetrifilmTM for estimating populations of total aerobic bacteria in various livestock products. 257 samples randomly selected in local retail stores and 87 samples inoculated with E. coli ATCC 25922, Staphylococcus aureus ATCC 12868 were tested in this study. The degree of agreement was estimated according to the CCFRA (Campden and Chorleywood Food Research Association Group) Guideline 29 and the agreement indicates the difference of two kinds methods is lower than 1 log base 10(log10). The samples of hams, jerky products, ground meat products, milks, ice creams, infant formulas, and egg heat formed products were showed above 95% in the agreement of methods. In contrast, proportion of agreement on meat extract products, cheeses and sausages were 93.1%, 92.1%, 89.1%, respectively. One press ham and five sausages containing spice and seasoning, two pork cutlets containing spice and bread crumbs, two meat extract product and two natural cheeses and one processing cheese with a high fat content, and one ice cream containing chocolate of all samples showed the discrepancy. Our result suggest that TEMPO®TVC system is efficient to analyses total aerobic bacteria to compare manual method in time-consuming and laborious process except livestock products having limit of detection.

This paper deals with the effects of the surfactant and preplate process (sensitization and activation) on electroless copper plating on carbon nano-fiber (CNF). Ultrasonic irradiation was applied both during dispersion of CNF and during electroless plating containing preplate process. The dispersion of CNF and flatness of the plated copper film were discussed based on the changes in surfactant concentration and preplate process time. It was clearly shown that high concentration of surfactant and long time of preplate process could promote the agglomeration of CNF and uneven copper plating on CNF.

Silver coated copper composite powders were prepared by electroless plating method by controlling the activation and deposition process variables such as feeding rate of silver ions solution, concentration of reductant and molar ratio of activation solution at room temperature. The characteristics of the product were verified by using a scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic absorption (A.A.). It is noted that completely cleansing the copper oxide layers and protecting the copper particles surface from hydrolysis were important to obtain high quality Ag-Cu composite powders. The optimum conditions of Ag-Cu composite powder synthesis were molar ratio 4, concentration of reductant 15g/l and feeding rate of silver ions solution 2 ml/min.

Ti 안경 태 의 nm 부분과 temple 부분을 분리 한 후， temple 부분을 시 료로 사용하 였다. 실험에 사용한 장비는 아크 이온플레이팅 장비이며， 이 장비를 이용하여 TiN과 TiC 이온도금을 하였다. Ti temple의 성분과 TiN, TiN 도금층과 TiC 도금층의 과 밀착성 시험을 행하였다. 그 결과， TiN temple은 Al을 첨가한 알파형 티탄테 temple이었으며， TiN 이온도금 층은 XPS data로부터 TiN으로， Ti와 결합을 잘하는 Oxygen이나 Carbon과의 결합 이 없다는 것을 알 수 있었다. 염수분무시험에서는 10 일이 경과 후에도 “이상없음”으 로 결과가 나왔으며， 이온도금층의 두께는 약 l.9 ]lm 이었다. 밀착성 시험에서 180。굽 혔을 때 도금층의 박리가 육안으로도 없었으며， 색상은 골드색에 가까운 색상이었다. TiC 이온도금층은 주로 TiC로 이루어져 있으며 N과 0가 약간 섞어있는 형태이었 다. 이온도금층의 두께는 약 l.6 jlm로 TíN 도금층보다 약간 작게 나왔으며， 염수분무 시험과 밀착성시험에서도 TiN 도금층과 같이 “이상없음”으로 결과가 나왔으며， 밀착 성 시험에서 도금층의 박리가 육안으로도 없었으며， 색상은 흑색이었다.

Ni-diamond composite powders with nickel layer of round-top type on the surface of synthetic diamond (140/170 mesh) were prepared by the electroless plating method (EN) with semi-batch reactor. The effects of nickel concentration, feeding rates of reductant, temperature, reaction time and stirring speeds on the weight percentage and morphology of deposited Ni, mean particle size and specific surface area of the composite powders were investigated by Atomic Adsortion Spectrometer, SEM-EDX, PSA and BET. It was found that nucleated Ni-P islands, acted as catalytic sites for further deposition and grown into these relatively thick layers with nodule-type on the surface of diamond by a lateral growth mechanism. The weight percentage of Ni in the composite powder increased with reaction time, feeding rate of reductant and temperature, but decreased with stirring speed. The weight percentage of Ni in Ni-diamond composite powder was 55% at 150 min., 200 rpm and 7 .

해양환경의 비저항 변화에 따른 모재, Ni도금 및 Cr도금의 분극저항, 부식전류밀도, 부식억제율 및 분극지배기구에 관하여 연구한 결과 다음과 같은 결론을 얻었다. 1) Cr도금 및 Ni도금의 분극저항은 모재의 분극저항보다 더 높게 나타나고, 이들 재료의 분극저항은 비저항이 감소함에 따라 낮아진다. 2) 비저항이 낮아질수록 Cr도금 및 Ni도금의 부식전류밀도는 모재의 부식전류보다 더 억제됨에 따라 Ni 및 Cr도금의 부식억제율은 더 높게 된다. 3) 해양환경의 비정항에 따른 모재, Ni도금 및 Cr 도금의 부식반응은 음극지배로 판단된다.(이 논문의 결론부분임)

무전해 PCB 도금 공정 수세액을 분리막으로 처리하여 투과수는 공업용수로 재사용하고 유가금속인 금(Au)을 회수하는 방법에 관하여 연구하였다. 역삼투 분리막 테스트 셀을 이용하여 수세액 처리에 적합한 분리막을 선정하였으며 scale-up을 위한 나권형 모듈 투과 실험을 실시하였다. 먼저, (주)새한에서 생산되는 RO-TL(tap water, low pressure), RO-BL(brackish water, low pressure), RO-normal(for water purifier)막으로 투과실험하였으며 그 중 RO-TL막이 soft etching, 촉매 및 Ni 수세액 처리에 우수한 것으로 판명되었다. 따라서 RO-TL막으로 제작한 나권형 가정용 정수기 모듈로 7bar, 25℃에서 scale-up 실험을 수행하였다. Au수세액의 투과 유속은 약 30 LMH로서 가장 높았으나 Au 제거율이 80% 미만이었다. Pd, Ni 및 soft etching 수세액의 투과유속은 각각 약 22, 17, 10 LMH 정도이며 Pd의 제거율은 85% 이상, Ni 및 Cu 제거율은 97% 이상이었다. 또한 Au, Ni 및 Cu 이온이 함유된 수세액 중 유가금속인 Au를 선택적으로 회수하기 위하여 NF막을 사용하였다. Au수세액 중 Ni 및 Cu 이온은 대부분 제거되었으며 투과액 중에 Au이온이 81.9% 존재하였고 계속하여 RO-TL막으로 Au를 농축 회수하였다. 마지막으로 4"직경의 NF 및 RO-TL 나권형 모듈을 연속적으로 사용하여 Au를 효과적으로 회수할 수 있음을 재확인하였다.인하였다.