Stage II B형 골육종에 대한 술전 항암화학요법 및 수술적 치료 결과

김정만,우영균,김형민,김훈교,이승구,강용구 가톨릭중앙의료원 가톨릭암센터 1997 암심포지움 Vol.- No.1

Recent advances in imaging techniques, surgery and combination anti-cancer chemotherapy have brought high survial rates in osteosarcoma. To investigate the survival rate, local recurrence and complications in treatment, we analysed 25 osteosarcoma cases who had been treated with preoperative neo-adjuvant chemotherapy, surgery and post operative chemotherapy at Department of Orthopedic Surgery, Catholic University. From May 1988 to April 1995, 42 cases of stage IIB osteosarcoma were admitted in Department of Orthopedic surgery. Among them, 17 cases who didn't follow our treatment guidance were excluded in this study. The average age were 19 years. There were 21 males and 4 females. The involved sites were 4 humerus, 10 femur, 10 tibia and 1 talus. Eleven cases had received intra-arterial cisplatin and intravenous adriamycin chemotherapy, and 7 T-10 protocol and 7 intravenous ifosfamide, ADR, methotrexate, cisplatin. Among twenty-three cases were treated with limb salvage surgery, and 2 amputation. The average follow-up was 35 months(3-82). There were 14 cases of continuous disease free, 9 cases of died of desease, 1 case of alive with disease, and 1 case of no evidence of disease at final follow-up. There were three cases of local recurrence at 6,8 and 12 months after operation. The Estimated kaplan-Meier's 5 year survival rates for all, ADR-cisloatin group, T-10 protocol group, and ifosfamide regimen group were 66%, 73%, 44% and 72%, respectively.

국산화 개발한 치과용 저금합금의 시효경화 거동

김교한,권오원,김형일 대한치과기재학회 1997 대한치과재료학회지 Vol.24 No.1

To define the optimum heat treatment temperature and time of the developed three types of low karat gold alloys, hardness test, DTA and x-ray diffraction methods were used. The results were as follows. *The optimum temperature of heat treatment was at 400℃ in K-Ⅰ, K-Ⅱ and K-Ⅲ alloys. *The proper time of age-hardening was 10 minute in K-Ⅰ alloy, and 10-30-minutes in K-Ⅱ alloys. *The stable phases of three types of low karat gold alloys were Ag-rich α₁ phase, Cu-rich α₂ phase and AuCuⅠ phase in case of K-Ⅰ alloy, and α1 phase and AuCuⅠ phase were coexisted in K-Ⅱ and K-Ⅲ alloy. *The cause of the decrease of hardness by overageing was the α₁ phase and AuCu Ⅰ phase, which were precipitated in the grain boundary.

치과 주조용 저금합금의 개발에 관한 연구

김교한,김형일 대한치과기재학회 1996 대한치과재료학회지 Vol.23 No.2

The purpose of this study was to develop the dental casting low carat gold alloys based upon Au-Ag-Cu ternary alloy. Three types of low carat gold alloy containing 46, 55 and 66wt. % of gold, content respectively, which were balanced with total amount of Au plus Ag of 74wt. %, were melted and casted to evaluate the mechanical properties, corrosion resistance, melting range and cytotoxicity. The obtained results were summarized follows : ·In mechanical properties, the type K-Ⅱalloys, which was increased in the amount of Pt component, showed 115MPa of yield strength, 400MPa of ultimate tensile strength and 150 of vicker's hardness value and these values are higher than those of K-Ⅰ, K-Ⅲ alloy of 30% in yield strength, 50% in ultimate tensile strength and 10% in hardness value. ·Age hardening effect was confirmed in all three alloys. ·Melting ranges of these alloys were in the range of 910-1050℃ ·Higher corrosion resistance was confirmed in the potential range of oral cavith. ·The cytotoxicity of alloys was evaluated by the cell growth and morphologic changes, Each alloy showed normal growth rate and cellular morphology.

치과 임플란트용 순 Ti의 접촉부식 거동

김교한,허만수,김형일,황운석,高田 雄京,奧野 攻 대한치과기재학회 1999 대한치과재료학회지 Vol.26 No.4

One of the fields in which titanium(Ti) is becoming increasingly valuable is the field of biomaterials. Ti had shown its good corrosion resistance, high strength to weight ratio, and compatibility with human tissues. Such applications of Ti in this area involve replacing stainless steel and cobalt-chromium alloy implant which are used in skull, shoulder joint, spine, and dental implant. In dental field, titanium has been used as dental implant, so it becomes necessary to examine and estimate the anti-corrosion ability of Ti and its alloys at the severe conditions such as crevice corrosion and galvanic corrosion. The purposes of this study was to examine the corrosion mechanisms of the pure Ti showing good corrosion resistance under an oral corrosion environment when it is coupled with dental casting Type Ⅱ and Type Ⅳ gold alloys. These coupling corrosion mechanisms were studied in three conditions. First was by measuring the resting potential of pure Ti, when it was uncoupled and coupled with Type Ⅱ and Type Ⅳ alloys. Second was by measuring anode polarization behavior of pure Ti, Type Ⅱ and Type Ⅳ alloys, and third was by detecting dissolved ions from the pure Ti, uncoupled and coupled with Type Ⅱ and Type Ⅳ gold alloys which were immersed in 0.9% NaCl solution for 7 days. The resting potential showed a low potential value at the initial stage but increasing into a high value (to 0.18 V) with time elapse and reached a stable value. On the contrary, the potentials of Type Ⅱ and Type Ⅳ gold alloys were in their values at the initial stage of immersion, then decreased with the time and reached stable values, being higher than the value of pure Ti. When pure Ti coupled with Type Ⅱ and Type Ⅳ gold alloys, the resting potential of coupled one was between the values of each one. When Type Ⅱ and Type Ⅳ gold alloys were coupled with pure Ti, there was an increase in Ag, Cu, and Zn. Also, Zn ions released the high potential precious metal alloys, compared to the uncoupled case. Ti ion was not detected at any cases of pure Ti or coupled with gold alloys. It was thought that one of the causes of the increase in Ag, Zn, and Cu ions when Ti was coupled with dental gold alloys was that Ag, Zn, and Cu ions were selectively dissoluted from the Ag rich regions around grain boundary and the casting defects. In conclusions, the results of this study suggest that the pure Ti was very stable when coupled with the gold alloys in oral cavity.

치과용 Au-Ag-Cu-Pd 합금의 시효경화특성

김형일,김영근,장명익,김교한 대한치과기재학회 1997 대한치과재료학회지 Vol.24 No.1

The relationship between the isothermal age-hardening behavior and the phase transformation process in a dental casting Au-Ag-Cu-Pd alloy was investigated by means of hardness test, X-ray diffraction study. 1. The isothermal age-hardening behavior in the 350∼450℃ temperature range showed a similar tendency in the changes. However, the initial hardening was faster and the maximum hardness was higher and the overaging with softening was slower on aging at the lower temperature. 2. By the isothermal aging at 350∼450℃, the metastable Ag-rica α₁’and AuCu Ⅰ’orderd phases were formed from the supersaturated α phase prior to the final formation of the equilibrium Ag-rich α₁’and AuCu Ⅰordered phases. 3. By aging at 450℃, the age-hardening was attributed to the lattice strains of the parent phases resulting from the transformation of the αphase resulting from the transformation to the metastable phases. The X-ray diffraction peaks of the αphase showed a distinct shift toward both the high and low diffraction angles during transformation.

TiO₂가 코팅된 Polyethylene 입자를 이용한 페놀과 톨루엔의 광분해

김동주,최상근,조준형,김교선 江原大學校 産業技術硏究所 2004 産業技術硏究 Vol.24 No.B

The photodegradation of phenol and toluene with the Ti0₂-coated polyethylene (PE) particles were investigated in the slurry type photocatalytic reactor, changing the Ti0₂ particle sizes, initial phenol and toluene concentrations, and the oxygen flow rate. The nano-sized Ti0₂ photocatalyst particles were prepared by the diffusion flame reactor and they were coated onto PE particles by using the hybridization system for the efficient recollection of Ti0₂- coated particles after photodegradation experiments. The degradation efficiencies of phenol and toluene with the Ti0₂-coated PE particles were more than 90% after photodegradation of 80 minutes for most cases. The efficiencies of photodegradation with the Ti0₂-coated PE particles were found to be lower than those by the pure Ti0₂ particles by 50%, because of the decrease in specific surface area of Ti0₂ particles in PE particles.

치과주조용 저카라트 금합금의 시효경화

김형일,김종렬,안호경,장명익,설효정,김교한 대한치과기재학회 1997 대한치과재료학회지 Vol.24 No.2

The age-hardening behavior of a commercial dental casting low-carat gold alloy was investigated by means of differential thermal analysis, hardness test, optical microscopic observation and X-ray diffraction study. The following results were obtained. 1. By the isothermal aging of this alloy at 300∼400℃, the hardness increased markedly at the initial stage and continued to increased gradually for the time, and then decreased dractically after longer aging time. 2. The hardening was attributed to the formation of the metastable AuCu I' ordered phase from the α matrix. 3. The overaging with softening was attributed to the precipitation of the fine lamellar structure which was composed of the Ag-rich α1 and AuCu I ordered phases.

레진접착제를 도포한 상아질에 대한 합착용 시멘트의 전단결합강도

김교철,우이형,이성복,최부병 慶熙大學校 齒科大學 1995 慶熙齒大論文集 Vol.17 No.2

The purpose of this study was to confirm the formation of hybrid layer and resin tags in dentin tissue and the possibility of bonding between luting cements used for the prosthesis and the resinous surface coated with resin bonding agents to prevent the dentin hypersensitivity after abutment preparation. Some resin bonding agents, which may have the possibility of bonding with polyacrylic acid as a liquid ingredient of polycarboxylate and glass ionomer cements, were selected. All-Bond desensitizer containing NTG-GMA and BPDM, Scotch-Bond Multipurpose plus containing HEMA, and XR-bond containing organophosphate were selected as a coating agent. Dental cements were zinc phosphate, polycarboxylate, and glass ionomer cement. After the exposed dentin surface of premolars was ethced with 10% phosphoric acid and coated with resin bonding agents, the morphology of treated surfaces and the resin tags and hybrid layers on sectioned surfaces were observed by SEM. Shear bond strength between the resin bonding agents and 3 kinds of cements was measured 24 hours after bonding. On the debonded surfaces of the shear bond strength tested specimens, the cement tags and the bonding sites between the resin materials and cements were examined by SEM. Following conclusions were drawn 1. Coating of dentin with resin bonding agents had no effect on the shear bond strength of zinc phosphate cement. 2. Both of polycarboxylate and glass ionomer cements showed the increased shear bond strength by the dentinal coating with Scotch-Bond Multipurpose plus containing HEMA. However, in the case of dentinal coating with some agents containing NTG-GMA and BPDM or organophosphate, polycarboxylate cement exhibited the lowered shear bond strength, and glass ionomer cement showed the unchanged shear bond strength. 3. Complete obstructions of dentinal tubules were observed on the dentin coated with All-Bond desensitizer or XR-bond, but distinct shape of the orifices of dentinal tubules was observed consistently on the dentin coated with Scotch-Bond Multipurpose plus. 4. The hybrid layer was thickest on the dentin coated with Al1'Bond desensitizer, and the length of resin tags was longest on the dentin coated with Scotch-Bond Multipurpose plus. 5. On the debonded specimens which had been bonded with polycarboxylate cement or glass ionomer cement after coating with Scotch-Bond Multipurpose plus, the cement tags and the bonding sites between the resinous surface and the cements could be examined.

선박용 유배출 감시 장치(ODME)를 위한 유분 농도계 설계

손교훈,이승희,김재형 國立 昌原大學校 産業技術硏究所 1998 産技硏論文集 Vol.12 No.-

본 논문에서는 태형 탱커선의 의무 장비인 유배출 감시 장비 (Oil Discharge Monitoring Equipment)를 위한 유분 농도계의 설계에 대하여 연구하였다. ODME는 국제해사기구(IMO)에서 규정된 ton 이상의 대형 선박에 의무적으로 설치하도록 규정하고 있으며 이는 날로 심각해지는 해양 오염을 방지하는데 목적이 있다. ODME의 구성요소 중 가장 중요한 것은 유분 농도계이며 이는 선박에서 배출되는 물에 포함된 유 성분을 ppm 단위로 계측하는 것이다. 본 연구에서는 선박에서 사용이 용이한 산란방식의 유분 농도계의 설게에 대한 농도 계산 알고리즘에 대하여 고찰하였으며 0~100ppm 범위에서 ±5%의 오차 이내로 측정이 가능함을 보였다. 이는 IMO의 규격에 만족하는 수치이다.

구상흑연주철들의 기지조직과 피로파면에 관한 연구

이종형,김교광 金烏工科大學校 2000 論文集 Vol.21 No.-

This study was carried out rotary bending fatigue test experiment with nodular cast iron, measured the hardness value of it and explained characteristic of the matrix structure. In GCD45 ferrite area ratio was roughly 40% and the fatigue limit value was 24kgf/㎟. In GCD60 ferrite area ratio was approximately 45% and fatigue limit value was roughly 31kgf/㎟, graphite grain size of GCD45 was roughly 17㎛ and GCD60 was roughly 23㎛, ferrite grain size of GCD45 was roughly 51㎛ and GCD60 was roughly 66㎛, so that the fatigue limit depended upon graphite grain size and ferrite grain size. it was found that when cracks approached near to graphite in fatigue crack occurring process, not went through it, but separated graphite and ferrite grain boundary and combined with other cracks to form large one.