• 미생물학회지
• /
• 제28권3호
• /
• pp.278-282
• /
• 1990

Diffusion and partition of progesterone into the polyacrylamide gel was examined. Diffusion coefficient of progesterone decreased down to an asymptotic value as the concentration of the organic solvents in the diffusing medium increased. However the partition coefficient diminished steadily. Crosslinking density in the gel didn't affected the diffusion coefficient considerably but lowered the partition coefficient due to the contraction of pore volume of the gel. Progesterone showed higher diffusion coefficient as well as partition coefficient in the polyurethane than in the polyacrylamide gel, which seems to be ascribed to the difference in hydrophobicity, pore volume and pore size of the polymer matrix.

• 한국대기환경학회지
• /
• 제2권2호
• /
• pp.41-50
• /
• 1986

Urban aerosol concentrations in the size range of $0.01 \sim 1.0 \mum$ have been measured by using an electrical aerosol analyzer from May through October, 1984. The total diurnal variation of the number concentration indicates that a minimum value is observed at 3 hr and a sharp increase is noticed early in the morning with a subsequent slow and continuous increase from around 7 hr until 20 hr. After that it is decreased to reach its minimum by dawn. However, both surface and volume concentrations have shown that their first maxima at 8 hr and their second at about 20 hr simultaneously. It is found that the aerosol number is mainly governed by the particles in the size range of $0.01 \sim 0.1 \mum$, while most volume is in $0.1 \sim 1.0 \mum$ size range. It is known fact that particles of $0.1 \sim 1.0 \mum$ size range affect the visibility reduction in the atmosphere. The monthly variation of aerosol concentration remarks its minimum in summer. The main factors influencing the aerosol concentration are emission of autoexhausts, various processes of production and removal, and meteorological parameters.

• 대한방사선치료학회지
• /
• 제28권1호
• /
• pp.65-75
• /
• 2016

목 적 : 유방보존술 이후 부분 유방 방사선 치료를 시행한 환자들의 치료 전후 장액종의 체적 변화를 분석하여 방사선 치료 효과 향상에 기여하고자 한다. 대상 및 방법 : 본원에서 ViewRay MRIdian System을 이용하여 부분유방방사선 치료를 시행한 환자 20명을 대상으로 하였다. 대상 환자들의 수술시 제거된 검체 크기를 구하고, 장액종의 체적 변화를 주(week)단위로 획득하였다. 획득한 체적을 바탕으로 나이, 수술 후 첫 치료시작까지의 기간, 체질량지수(BMI), 수술시 적출된 검체 크기 등을 기준으로 하여 비교하였다. 그리고 부분 유방 방사선 치료의 특정용적을 구하기 위해 PTV(=seroma volume + margin)를 기준으로 ViewRay MRIdian RTP System을 이용하여 분석하였다. 결 과 : 모의치료 MRI 촬영 후 첫 치료 시까지 1주일간 나타난 장액종의 체적 변화는 0~5%가 8명, 5~10%가 2명, 10~15%가 3명, 15~20%가 2명, 그리고 20% 이상이 5명 이었다. 가장 큰 변화를 보인 2명의 환자 중, A환자는 기존 치료계획에서 처방선량 100%의 용적이 213.08 cc, PTV는 181.93 cc, 장액종의 체적은 15.3 cc였으나, 보정치료계획에서 장액종의 체적이 5.3 cc로 65.36% 감소하면서, 처방선량 100%의 용적은 205.83 cc, PTV는 102.54 cc로 각각 3.4%, 43.6% 감소하였다. B환자는 장액종의 체적이 20.2 cc에서 11.6 cc로 42.57% 감소하였고, 이로 인해 처방선량 100%용적은 8.1%, PTV는 40% 감소하였다. 결 론 : 장액종의 체적 변화는 고령일수록, 수술 후 치료가 시작되는 기간이 짧을수록, 검체의 크기가 100 cc이하 일수록 큰 것을 확인하였다. 부분유방방사선치료 환자의 경우 전체유방방사선치료의 환자보다 체적 변화에 따른 Dose conformity가 더욱 민감하므로, 지속적인 관찰을 통해 각 환자의 장액종 체적 변화에 따른 보정치료계획을 수립하여 치료하는 것이 바람직하다고 사료된다.

• 소성∙가공
• /
• 제11권8호
• /
• pp.682-690
• /
• 2002

The formation of adiabatic shearband in tungsten heavy alloys(WHA) was studied in this investigation. Five prismatic specimens were loaded by high velocity impacts and treated as plane strain problems. To find out the effect of particle's volume ratio, specimens containing 81%, 93% and 97% volume percents of tungsten particles were used. Also the effects of particle's geometry and size on the formation of shearband were studied for 81% volume percent alloys by small size particle model, large size particle model and undulated particle models, and the results were discussed.be used to diagnose the causes of necking and fracture in industrial practice and to investigate whether these defects were caused by material property variation, changes in lubrication, or incorrect press settings. In non-axisymmetric deep drawing, three modes of forming regimes are found: draw, stretch, plane strain. The stretch mode for non-axisymmetric deep drawing could be defined when the major and minor strains are positive. The draw mode could be defined when the major strain is positive and minor strain is negative, and plane strain mode could be defined when the major strain is positive and minor strain is zero. Through experiments the draw mode was shown on the wall and flange are one of a drawn cup, while the plane strain and the stretch mode were on the punch head and the punch corner area respectively, We observed that the punch load of elliptical deep drawing was decreased according to increase of die corner radius and the thickness deformation of minor side was more large than major side.

• Bulletin of the Korean Chemical Society
• /
• 제5권3호
• /
• pp.112-117
• /
• 1984

The association constants (K) of 3,5,N-trimethyl pyridinium iodide in 95 volume percent ethanol-water mixed solvent were determined by a modified UV and conductance method at $25^{\circ},\;30{\circ},\;40{\circ}\;and\;50{\circ}C$ over the pressure range 1 to 2000 bars. The association process is enhanced with increasing pressure and decreasing temperature. From K values, we obtained the total partial molar volume change (${\Delta}V$) and some thermodynamic parameters. The electrostriction volume (${\Delta}V_{el}$) and intrinsic volume (${\Delta}V_{in}$) were also evaluated. The values of ${\Delta}V,\;{\Delta}V_{el},\;{\Delta}V_{in}$ are negative, negative and positive, respectively, and the absolute values of all these three decrease with increasing pressure and temperature. The ion-pair size (a) were varied 3 to 6 ${\AA}$, with pressure and temperature. The solvation number (n) decreased from 2 to 0.5 with increasing temperature.

• 동력기계공학회지
• /
• 제11권1호
• /
• pp.115-120
• /
• 2007

The effect of grain size on the damping capacity of Fe-26Mn-2Al alloy studied in this paper has been investigated after changing the microstructure by cold rolling and changing grain size. Micro structures in Fe-26Mn-2Al at room temperature consist of a large quantity of austenite and a small quantity of ${\varepsilon}\;and\;{\alpha}'$ martensite. And ${\varepsilon}\;and\;{\alpha}'$ martensite was increased by increasing the degree of cold rolling. The content of deformation induced martensite was increased with increasing the degree of cold rolling. Damping capacity was linearly increased with increasing ${\varepsilon}$ martensite content, which suggests that stacking faults and ${\varepsilon}$ martensite variant boundaries are the principle damping sources. With increasing the grain size in Fe-26Mn-2Al alloy, the damping capacity was increased due to increasing the volume fraction of ${\varepsilon}$ martensite by decrement in stability of austenite phase. With decreasing the grain size, the content of deformation induced martensite was decreased and the damping capacity was decreased.

• 한국관개배수논문집
• /
• 제17권2호
• /
• pp.57-70
• /
• 2010

This study was performed to analyze the affect of water supply capacity followed by allocating flood control volume in heightening reservoir, of which Baekgog reservoir was selected as a case study in here. Baekgog reservoir is located in Jincheon county, Chungbuk province, of which full water level will be heightened from EL. 100. 1m to EL. 102.1m, and total storage from 21.75M $m^3$ to 26.67M $m^3$. Flood inflow with 200year frequency was estimated to 997 $m^3$/s in peak flow and 22.54M $m^3$ in total volume. Reservoir flood routing was conducted to determine flood limited water levels, which was determined to have scenarios such as EL 97-98-99m in periods of 6.21.-7.20., 7.21.-8.20., and 8.21.-9.20., respectively, EL 97-97-97m, EL 98-98-98m in present reservoir, and EL 99-100-101m, EL 99-99-99m, and EL 100-100-100m in heightened reservoir. Reservoir inflow was simulated by DAWAST model. Annual paddy irrigation requirement was estimated to 33.19M $m^3$ to 2,975ha. Instream flow was allocated to 0.14mm/d from October to April. Operation rule curve was drawn using inflow, irrigation and instream flow requirements data. In case of withdrawal limit reservoir operation using operation rule curve, reduction rates of annual irrigation supply before and after flood control by reservoir were 2.0~4.3% in present size and 1.5~3.6% in heightened size. Reliability on water supply was decreased from 77.3% to 63.6~68.2% in present size and from 81.6% to 72.7~79.5% in heightened size. And reduction rates of water storage at the end of year before and after flood control by reservoir were 7.3~16.5% in present size and 7.7~16.9% in heightened size. But water supplies were done without any water deficiency through withdrawal limit reservoir operation in spite of low flood regulating water level.

• 대한영상의학회지
• /
• 제82권6호
• /
• pp.1534-1544
• /
• 2021

목적 전산화단층촬영에서 호흡에 의한 폐 용적의 변화가 폐 반고형결절의 크기와 용적에 미치는 영향을 알아보고자 한다. 대상과 방법 총 31명의 환자에서 42개의 반고형결절이 연구에 포함되었다. 먼저 총 폐활량 상태에서 전산단층화촬영을 시행 받은 후, 결절이 포함된 부분만 일호흡용적 상태에서 추가로 촬영하였다. 각각의 반고형결절의 직경과 용적을 측정하였고, 전체 폐 용적은 결절의 중심이 있는 동측 폐의 단면적으로 추정하였다. 동일한 개인 내에서 총 폐활량과 일회 호흡량 간 측정값 변화의 유의성을 통계적으로 평가하였다. 결과 총 폐활량 상태와 비교하였을 때, 일회 호흡용적 상태에서 폐 단면적은 평균 12.7 cm², 반고형결절의 직경 및 용적은 평균적으로 각각 0.5 mm와 46.4 mm³ 감소하였다(p < 0.001). 총 폐활량 상태와 일호흡량 상태 간 폐 면적 변화는 반고형결절의 직경 변화(rho = 0.341; p = 0.027) 및 부피 변화(rho = 0.401; p = 0.014)와 유의한 양의 상관관계를 보였다. 그러나 폐 용적의 변화를 고려하여 보정한 후에는 반고형결절의 평균 직경과 부피가 총 폐활량 상태와 일호흡량 상태 간 유의한 차이가 없었다(각각 p = 0.062, p = 0.124). 결론 전산화단층촬영에서 측정한 반고형결절의 크기와 용적은 동일한 환자 내에서도 촬영 당시의 폐 용적에 유의한 영향을 받는다.

• 펄프종이기술
• /
• 제34권3호
• /
• pp.53-58
• /
• 2002

This paper was performed to investigate the effect of pore structure on ink residual behavior. To prepare different coating structures as substrates against inks, fine, medium and coarse calcium carbonate were used in the coating color. It is well known ink properties can affect to print qualities. After printing on the coated paper, ink layer can consider as third structure addition to paper and coating layer. To compare effect of ink properties on the surface structure and print qualities, several properties of ink were also adopted as raw material. Particle size of pigment effect on gloss evaluation of coated paper increased with calendering. It was shown that ink transfer rate increased as surface of the sample was smooth. The ink contained low viscosity resin evaluated more print gloss. Finer pigment particle size, smaller pore size and higher porosity. Pore volume of coated paper was slightly decreased with printing as the coating was prepared with the finest particle size. However, it founded that ink resin could not affect on pore volume and distribution of printed paper

• Biomolecules & Therapeutics
• /
• 제20권2호
• /
• pp.239-244
• /
• 2012

This study examined the inhibitory effects of 4-guanidinobutyric acid (4GBA), an alkaloid, against gastric lesions by assessing the inhibition of Helicobacter pylori (H. pylori) and gastric cancer cells. Acute and chronic gastritis were also observed using HCl/ethanol (EtOH) and indomethacin-induced gastric lesion models, respectively. 4GBA inhibited the growth of H. pylori in a dose dependent manner, and showed acid-neutralizing capacity. In the pylorus ligated rats, 4GBA decreased the volume of gastric secretion and gastric acid output slightly, and increased the pH. 4GBA at a dose of 100 mg/kg reduced the size of HCl/EtOH-induced gastric lesions (70.8%) and indomethacin-induced gastric lesions (38.8%). The antigastritic action of 4GBA might be associated with the acid-neutralizing capacity, anti-H. pylori action, and decreased volume of gastric secretion. These results suggest that 4GBA might be useful in the treatment and/or protection of gastritis.