해캄의 성분분석에 관한 연구

서정목,구길서 공주대학교 사범대학 과학교육연구소 1992 과학교육연구 Vol.23 No.1

As the last treatment of waste water, harvest of algae and the use of the algae as animal feed have been researched in other countries. Spirogira is a sort of green algae. The components of the algae were analysed: moisture, protein, lipid, fiber, sugar, ash (Ca, P, Fe). Especially protein content of the algae was high as sea weed. So, the spirogyra can be used as an animal feed.

다공성 킬레이트 수지의 제조와 우라닐 흡착에 관한 기초연구

서정목 공주대학교 사범대학 과학교육연구소 1999 과학교육연구 Vol.30 No.1

차세대 에너지 원료로 주목받고 있는 우라닐을 해수로부터 효율적으로 회수하기 위하여, 아미드 옥심기가 도입된 graft type, deposition type, spinning type의 다공성 킬레이트 수지를 제조하여 이들의 우라닐 이온의 흡-탈착 실험을 하였다. 본 기초연구에서 deposition type 흡착제 우라닐 회수 효율이 가장 좋은 것으로 나타났다. For economical recovery of the uranyl ion from sea water, we prepared the graft type, the deposition type, and the spinning type of porous chelate resine. And we tested the adsorption-desorption abilities of the adsorbents for the uranyl ion in artificial sea water. From this basic study, we knew that the deposition type polymer is the best one of the adsorbents.

EDPM 가황 고무의 가교 밀도와 파괴 특성

徐延穆,柳百能,孟學永 公州大學校 基礎科學硏究所 1994 自然科學硏究 Vol.3 No.-

가교밀도가 다른 몇가지 EDPM 가환물을 제조하여, 가교밀도가 탄성체의 기계적 성질에 미치는 효과등을 검토하였다. 가교밀도가 증가할수록 유리전이온도가 증가하였다. 팬텀모델이 가교밀도를 결정하는데 최적이었다. 문턱 개열에너지는 29~127J/m2 범위로 판명되었다. Several samples of the EPDM vulcanizates with various crosslink density(XLD) are prepared by changing the addition amounts of surf fur and ENB. The XLD data are obtaned from experiments, such as the swelling and stress, and their effects on the mechanical properties of the elastomer are studied. The XLD is increased as the amount of sulfur and ENB increased and the density of elastomers, the amount of gel, and the glass transition temperature increased accordingly, while the molecular weight between crossllinking points of the network(Mc) decreased. The XLD data obtained from swelling and stress experiments are due to the physical constraints on the juntion position imposed by surrounding chains. It was also found that the phantom model gives better agreement in determining XLD than the affine model with the experimental data. Hysteresis ratio is found to be increasing as the strain rate, tear energy, and Mc increased, and as the XLD decreased. It is also found that the storage modulus increased as the XLD increased in the dynamic mechanical properties. The 100% modulus are also found to be increasing as the XLD increased, and a linear relationship of M100=0.124×10-4N0+0.74 is obtained. The tear energy increased as the tear rate and temperature also found to be a linear function of the XLD, and the threshold tear energy is a range of 29∼127J/m2.

고분자에 고정된 유기주석 촉매의 합성

徐延穆,吉德洙,孟學永 公州大學校 基礎科學硏究所 1994 自然科學硏究 Vol.3 No.-

공중합체 내의 염소 성분의 함량 변화는 methylal을 용매로 사용하였을때 3% 가교도의 공중합체가 최대이었으며 그 이상의 가교도를 지닌 공중합체에서는 거의 동일하였다. 팽윤율은 Methylal 용매중에서 3% 가교화 ST-DVB 공중합체가 최대로 팽윤되었으며 그 이상의 가교도를 지닌 공중합체에서는 자동가교의 영향으로 인하여 거의 일정하였다. ST-DVB 공중합체의 다공도 변화는 가교도가 5%일때 최대였으며 그 이상에서 거의 일정하였다. Crosslinked ST-DVB Copolymer was Chloromethylated, vinylated, and orgnometalated. When degree of crosslinkage was 3%, the chlorine content and the degree of swel ling of the polymer was highest in methylal solvent. The pore volme is highest in 5%-crosselinked polymer.

아크릴계 고분자 - Cu (Ⅱ)착물의 전기전도성

서정목,송해영 공주대학교 사범대학 과학교육연구소 1988 과학교육연구 Vol.20 No.1

Acrylic polymers such as polyacrylonitrile, poly(acryl-onitrile-co-4-vinyl pyridine), poly(acrylonitrile-co-acrylicacid) were prepared. And then the polymers-cu(Ⅱ)complexes were prepared. We studied on the electrical conductivities of the complexes. The results were below. The resistivity of PAN-Cu(Ⅱ) complex was about 10⁴Ω-cm, and it had the lowest value at PH 11. The good Electrical conductivity could be shown when the Iodine amount was above 1 perlent. and cupric chloride amount was above l percent, and cupric chloride amount was above l percent, and cupric chloride amount was above 20 percent. The electrical conductivities of th PAN-4VP-Cu(Ⅱ) complex and the ANAA-Cu(Ⅱ) complex showed all about 10-5 Ω -¹cm-¹.

SJO¨GREN'S SYNDROME 환자에게 즉시 임프란트 술식을 행한 치험례

최정환,손동석,이지연,이윤서,안선희,이재목 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.5

The old edentulous patients experience xerostomia commonly. They have considerable difficulty in wearing tissue-supported prosthesis and high risk rate of caries. One of them is Sj□gren's syndrome patient. Sj□gren's syndrome is a chronic inflammatory autoimmune disorder that results in a lymphocyte-mediated destruction of exocrine glands. We planned to place implants immediately after extraction in this case of autoimmune disease. The advantages of immediate implant placement include considerable decrease in time from tooth extraction to placement of the final prosthesis, fewer surgical procedures, and better acceptance of the overall treatment plan. We present a case of Sj□gren's syndrome patient treated with immediate implant placement & immediate loading in anterior region and immediate implant placement in posterior region.

B -NSF계 & 빈졸계 고분자로 변성된 인조석의 물성에 관한 기초 연구

조헌영,서정목,박성기 공주대학교 방재연구센터 1998 공주대학교 방재연구센터 논문집 Vol.2 No.-

In the recent years, artificial stone has been used as exterior finishing materials of bullding. Artificial stone is manufactured with mixture of cement, stone powder and light-weight aggregate. In this research, we tried to find a way of inceasing the properties needed for better quality artificial stone. So, we used β-NSF modifier and vinsol modifier to improve the physical properties of artifical stone. Through this research, we found that the optimum dosage of the β-NSF & the vinsol polymer is 0.1 wt% and 0.05wt% of cement.

Poly-(acrylic acid-co-methylacrylate)합성조건에 따른 시멘트계 재료의 물성

조헌영,서정목,이효진,이기환,김진만,맹학영 공주대학교 생산기술연구소 2000 論文集 Vol.8 No.-

The water soluble polymers based on polycarboxlates are come into the spot-light in the detergent fields of CaCO_3, Al(OH)_3 and leather industries. In this research, we synthesized molecular weights(Mn) by changing the concentrations of monomer(acrylic acid-methylacrylate mixture), chain transfer agent(butanethiol) and initiator(ammoniumpersulfate). We investigated the influences on the fluidities(the flow & the mini slump) and the setting times of cement material admixtured with the copolymers by the statistical method. The optimum synthesis formulation of the poly-(AA-co-MA) for cement materials is at the concentrations of monomer 50 M%, chain transfer agent 6.0 M% and initiator 2.0 M%. The number-average molecular weight of that was decided on 7,600 by the viscosity method.

피혁 분으로 변성된 석고계 재료의 물성

조헌영,서정목,전기석,이기환 공주대학교 생산기술연구소 2000 論文集 Vol.8 No.-

Gypsum materials have strong mechanical strengths and great resistance to fire. Also these one are very cheap because of the gypsum is a byproduct from chemical plants. But, these materials have some demerits ; weak water-resistance, heavy specific gravity and low physical properties in bending and tensile strengths. While, leather shaving dust(LSD) is very much produced from leather manufacturing process. The LSD is composed of collagen fibers which is a kind of protein. This one has strong tear and tensile strengths because of the collagen fibers are cross linked during the tanning process of leather. Also the dust has the properties of the high hygroscopic and the superior thermal insulation, but is not degraded any more in neutral condition such as gypsum slurry. In this paper, we have reinforced the physical properties of gypsum with LSD as a filler. From this research, it is decided that the optimum dosage of LSD to gypsum is below 5%(w/w) of the gypsum, and the specific gravity of LSD-gypsum mixture is reduced to 30% relative to gypsum alone.

멜라민-페놀 수지와 폐 피혁 분으로 만든 복합체의 물성

조헌영,서정목 공주대학교 자원재활용 신소재 연구센터 2002 센터사업 성과집 Vol.- No.1

The leather-resin(ST-MP) composites were made with leather shaving dust(ST) and melamine-phenol resin(MP) by hot pressing method. The mixing ratio of MP:ST, the hot pressing time and the hot pressing temperature for the composites were selected to the experimental factors in this experiment. The physical properties, such as the tensile and the flexural strengths and the extension at maximum of the composite, were tested. From L_9(3^4) orthogonal test, it is found that the ST-MP composites which have tensile strength : 5.8∼12.4 MPa, flexural strength : 20.2∼33.8 MPa, extension at maximum : 0.23∼0.44% are made in this conditions of MP mixing ratio : 150∼200%, hot pressing time : 7∼9 min, and hot pressing temperature : 179∼190℃.