• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04b
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• pp.134-138
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• 2000

The physical, electrical and piezoresitive characteristics of CrN(chromiun nitride) thin-films on silicon substrates have been investigated for use as strain gauges. The thin-film depositions have been carried out by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-(5~25 %)$N_2$). The deposited CrN thin-films with thickness of $3500{\AA}$nd annealing conditions($300^{\circ}C$, 48 hr) in Ar-10 % $N_2$ deposition atmosphere have been selected as the ideal piezoresistive material for the strain gauges. Under optimum conditions, the CrN thin-films for the strain gauges is obtained a high electrical resistivity, $\rho=1147.65\;{\mu}{\Omega}cm$, a low temperature coefficient of resistance, TCR=-186 ppm/$^{\circ}C$ and a high temporal stability with a good longitudinal gauge factor, GF=11.17.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.135-141
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• 2000

The physical, electrical and piezoresitive characteristics of CrN(chromiun nitride) thin-films on silicon substrates have been investigated for use as strain gauges. The thin-film depositions have been carried out by OC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-(5~25 %)$N_2$). The deposited CrN thin-films with thickness of $3500{\AA}$ and annealing conditions($300^{\circ}C$, 48 hr) in Ar-10 % $N_2$ deposition atmosphere have been selected as the ideal piezoresistive material for the strain gauges. Under optimum conditions, the CrN thin-films for the strain gauges is obtained a high electrical resistivity, $\rho=1147.65\;{\mu}{\Omega}cm$, a low temperature coefficient of resistance, TCR=-186 ppm/$^{\circ}C$ and a high temporal stability with a good longitudinal gauge factor, GF=11.17.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.04a
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• pp.115.3-115
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• 1979

중금속을 함유한 13종의 질산염을 명 농도별로 첨가하여 주정효모 Saccharomyces cerevisine의 주정생산과 발효작용에 미치는 영향을 조사하였다. 1. 일반적으로 중금속을 함유한 질산염은 그 첨가량이 0.0001mo1. 보다 고농도일수록 Saccharo-myces cerevisiae의 발효작용을 점차 억제하였다. 2. Nickel nitrate, chromium nitrate들의 0.0001 moi.의 첨가는 Saccharomyces cerevisiae의 alcohol 발효작용을 약간촉진시켰다. 3. Cadmium nitrate 0.001mo1. 이상, cupric nit-rate, nickel nitrate, cobalt nitrate 0.01mo1. 이상, 그리고 silver nitrate, mercurous nitrate, manganese nitrate, zinc nitrate, lead nitrate, chromiun nitrate, ferric nitrate, bismuth nitrate 0.1mol. 의 농도에서 Saccharomyces cerevisiae 의 발효작용은 완전히 조지되었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.343-346
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• 1997

This paper presents the basic characteristics of Cr thin-film, which were deposited on glass by DC magnetron sputtering. The optimized deposition condition of Cr thin-film strain gauges were input power 7w/cm$^2$and the Ar working pressure was 9mtorr. GF(Gauge Factor), TCR(Temperature Coefficient of Resistance) and TCS(Temperature Coefficient of Sensitivity) of Cr thin-film strain gauges were 5.86, 400 ppm/$^{\circ}C$ and 0 ppm/$^{\circ}C$, respectively.

• Journal of the Korean institute of surface engineering
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• v.21 no.4
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• pp.149-159
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• 1988

Electrodeposition of chromium from low concentration chromjum (III) sulfate complexess in aqueous using sodium formate-glycine mixtures as a complexing agent was studied. In the bath formation, it is found that the optimum again temperature and time for equilibration of the electrolytes are nrcessary for 24 hrs at 45$^{\circ}C$and the optimum elecrical charge for low current electrolysis which might be produced Cr(II) ions in the electrolytes is necessary for minum 2Ah/$\ell$. The optmun concentration off standard electrolyte for main composition is 0.05M chromium(III) sulfate, 0.2M sodium formate-0.2M glycine, and I mMNaSCN as a catalysea, respectivwly. The standard electrolyte is shows good covering, good throwing power, and 6% of current efficiency (Cr(III)basis). The oppearance of electrodeposits shows att active bright chromium. The SEM morphology of the chromjum coating is observed as smooth surfaces and dispersed micro prcro pores. X-ray diffraction analysis shows a bcc structure which the perferred orintation of the chromium electrodeposits is strongin(200)plane.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.692-695
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• 1999

This paper presents annealing characteristics of CrN thin-film strain gauges, which were deposited on glass by DC reactive magnetron sputtering in an argon-nitrogen atmosphere)Ar-(5-~25%)$N_2$. The physical and electrical characteristics of these films investigated with the thickness range 3500$\AA$ of CrN thin films, annealing temperature (100~30$0^{\circ}C$) and annealing time (24-72hr) . The optimized condition of CrN thin-film strain gauges were thickness range of 3500$\AA$ and annealing condition(30$0^{\circ}C$ , 48hr) in Ar-10%$N_2$ deposition atmosphere. Under optimum conditions, the CrN thin-films for strain gauge is obtained a high resistivity, $\rho$=1147.65$\Omega$cm a low temperature coefficient of 11.17. And change in resistance after annealing for the CrN thin film were quitely linear and stable.

• Journal of the Korean institute of surface engineering
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• v.30 no.2
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• pp.104-110
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• 1997

Conventional hexavlent chromium electroplating baths deposit the matal at low cathode efficiency and have poor covering and throwing power. The processs also generate hazardous wastes. To overcome many of the disadvantages of hexavalent chromium plating the use of trivalent chromium has advocted. After Yoshida, who first studied trivalent chromium plating, using ammonium sulfate and urea, there are numerous report describing the trivalent chromium electropating process using complexing agents. This study investigaten trivalent chromium plating electrolyte solutious containing formate as a complexing agent and ammouim chloride for conducting agent. The effects of composition and operating conditions on deposits and current efficiencies were investigated in trivalent chromium plating baths by analyzing the relationship pulse conditions and surface morphology The surface morphology of the deposits was observed by SEM. pulse electrolysis has been effective on obtaining a smooth with high current efficiency comparing with D.C. electrolysis in trivalent chromium solution.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1989-1991
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• 1999

This paper presents characteristics of CrN thin-film strain gauges, which were deposited on glass by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-$(5{\sim}25%)N_2$). The physical and electrical characteristics of these films investigated with the thickness range $3500{\AA}$ of CrN thin films, annealing temperature $(100{\sim}300^{\circ}C)$ and annealing $(24{\sim}72hr)$. The optimized condition of CrN thin-film strain gauges were thickness range of $3500{\AA}$ and annealing condition($300^{\circ}C$, 48 hr) in Ar-10 %$N_2$ deposition atmosphere. Under optimum conditions, the CrN thin-films for strain gauge is obtained a high resistivity, ${\rho}=1147.65{\mu}{\Omega}cm$, a low temperature coefficient of resistance, TCR=$-186ppm/^{\circ}C$ and a high temporal stability with a good longitudinal, 11.17. And change in resistance after annealing for the CrN thin-films were quitely linear and stable.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.573-576
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• 2000

The physical, electrical and piezoresitive characteristics of CrN(chromium nitride) thin-films on silicon substrates have been investigated for use as strain gauges. The thin-film depositions have been carried out by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-(5∼25 %)Na$_2$). The deposited CrN thin-films with thickness of 3577${\AA}$ and annealing conditions(300$^{\circ}C$, 48 hr) in Ar-10 % N$_2$deposition atmosphere have been selected as the ideal piezoresistive material for the strain gauges. Under optimum conditions, the CrN thin-films for the strain gauges is obtained a high electrical resistivity, $\rho$=1147.65 ${\mu}$$\Omega$cm, a low temperature coefficient of resistance, TCR=-186 ppm/$^{\circ}C$ and a high temporal stability with a good longitudinal gauge factor, GF=11.17.

• Journal of Korean Public Health Nursing
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• v.16 no.1
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• pp.190-200
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• 2002

This study was carried out to investigate and analyze TSP of the PC rooms. The concentration of the total suspended particulate and heavy metals contained in the total suspended particulate of the 15 PC rooms located in one local city were measured. The statistical correlation coefficients between the total suspended particulate and factors of the indoor condition (number of fan or size of pc room, illumination), between the heavy metals and factors of the indoor condition were studied. The results are as follows: 1. The factors of the indoor condition of the 15 PC rooms are as follows. Average illumination was 24 luxes. Average number of computers installed were 37. Average number of the fans was 7. and the size of investigated PC rooms was $139.94m^2$. 2. The mean age of the subjects was 21.8 years old. they $(51.5\%)$ used the 15 pc rooms for fewer than 2 hours per one day. 3. The mean concentration of total suspended particulate (TSP) is lower in the evening ${139.085\;(2.462)\;{\mu}g/m^3}$ than the night ${166.216(2.609){\mu}g/m^3}$. 4. The mean concentration of total suspended particulate was industrial work area) residential area) commercial area. 5. The distribution of heavy metals were indicated as Zn>Cr>Pb>Cd in the indoor air at PC rooms. and the concentration rate of Zn was the highest among heavy metals. but this increase didn't show any relationship with many factors of indoor condition (number of fan or size of pc room, lighting) 6. The concentration of TSP & heavy metals didn't have any relationship between the factors of indoor environment (number of fans, size of pc room, lighting).