• 유기물자원화
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• 제3권1호
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• pp.73-83
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• 1995

본 실험은 옥수수에 대한 정수장 슬러지 (Alum 슬러지)의 시용효과와 다양한 pH별로 용출된 alum슬러지 추출물이 옥수수의 유식물 생육에 미치는 영향을 평가하기 위해서 수행되었다. Alum슬러지와 부숙된 Alum슬러지 퇴비를 각각 1500kg/ha를 시용하여 옥수수를 재배한 결과 수량, 엽록소함량, 초장 등의 평가에서 대조구에 비해서 비효가 인정되었으며, 뚜렷한 비해 현상은 나타나지 않았다. 처리구별 옥수수의 종실에 대한 식품화학적 분석에서도 뚜렷한 성분 변화는 발견되지 않았다. pH에 대한 옥수수 유식물의 생육은 pH4 미만에서 지상부와 지하부의 생육저해가 나타났으며 무기이온의 흡수는 pH4 이하에서 크게 장해를 받는것으로 나타났다. 반면 alum슬러지의 추출물에서는 pH가 낮아지면서 지속적인 생육저해와 양이온 흡수저해가 나타났다. 또한 Aluminum함량이 100ppm 이하에서 극심한 생육저해가 나타났다.

• 한국염색가공학회지
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• 제16권1호
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• pp.26-33
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• 2004

Two reactive disperse dyes having $\alpha$-bromoacrylamide or acrylamide group were synthesized and their dyeing properties were compared with a disperse dye. Dyeing properties of reactive disperse dyes were strongly influenced by the chemical structure of reactive group. The amount of absorbed reactive disperse dye containing $\alpha$-bromoacrylamide group on polyester fiber was less than the disperse dye, and that on nylon fiber was much higher. When polyester and nylon fiber were simultaneously dyed in a dye pot, nylon fiber absorbed the reactive disperse dye more than polyester fiber. The reactive disperse dye having acrylamide group could reduces difference in color depth to a large extent, but the application of carrier or variation of dyebath pH were not sufficient for giving the same color depth to both fibers. The N/P union fabric could be dyed with the reactive disperse dye and its wash fastness were good to excellent.

• Journal of Magnetics
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• 제1권1호
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• pp.51-54
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• 1996

The effects of additional P-doping on the magnetic properties, thermal stability and cation distribution of Co-doped ${\gamma}-{Fe_2} {O_3}$have been investigated by means of magnetic annealing and measurements with vibration sample magnetometer and torque magnetometer. It is found that the P-doping promotes the coercivity and its magnetic-thermal stability, which may be attributed to increase of the cubic magneto-crystalline anisotropy constant, $K_1$ and the activation energy, E, for cation rearrangement, respectively. The cation distribution of P and Co-substituted iron oxide was calculated from the variation of the saturation magnetization with P-doping on the basis of the Neel model. It was found that the most of P ions in the iron oxides occupied the B-site of spinel lattice.

• Journal of Genetic Medicine
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• 제6권1호
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• pp.56-61
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• 2009

목 적: 자간전증은 유전적 환경적 요인에 의해 발생하는 다요인성 질환이다. 최근 네덜란드 산모에서의 자간전증 후보 유전자로 확인된 STOX1 유전자는 태반에서 발현되며 모계 대립유전자의 선택적 유전에 의해 각인된다. 본 연구에서는 STOX1 유전자의 단일염기변이형 부위인 Y153H와 한국인 자간전증의 연관성에 대하여 알아보고자 하였다. 대상 및 방법: 자간전증 산모 202과 임신기간 동안 자간전증이 발생하지 않은 정상 산모 204명의 혈액으로부터STOX1 유전자의 Y153H 변이 양상을 SNapShot assay kit와 ABI Prism 3730 DNA analyzer를 사용하여 분석하였다. 결과: STOX1 Y153H 변이의 유전자형 빈도는 자간전증환자군과 정상 대조군 간에 유의한 차이가 없었다(P>0.05). 또한 자간전증 환자군(87.1%)에서 대립유전자형인 H의 빈도도 정상 대조군(86.5%)과 유사하였다. 다중회귀분석결과 YH, HH, YH/HH 유전자형들은 자간전증 발생 위험에 있어서 연관성이 없었다. 결 론: 본 연구진은 처음으로 한국인 자간전증 환자에서 STOX1 유전자의 Y153H 변이형의 특징을 파악 하였다. 연구결과 자간전증 산모와 정상 산모 간의 유전자형과 대립유전자형의 빈도는 차이가 없었다. 비록 실험 대상군의 수적인 제한이 있지만, 이상의 결과를 통해서 한국인에서 STOX1 유전자의 Y153H 변이형은 자간전증과 연관성이 없는 것으로 사료된다.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제4권3호
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• pp.173-183
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• 2000

This study measured the zeta potential of both latex colloidal particles with carboxylate surface groups and glass beads (collectors) with silanol surface group employing various solution with different chemical characteristics. The results have been compared with the surface chemistry theory. The zeta potential of the particle and collector increased with increasing pH up to 5.0 regardless of the solution chemistry. For a monovalent electrolyte solution(sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (calcium chloride solution). In other words, the more the pH decreases, the larger the effect of neutral salts, such as NaCl and CaCl$_2$, have on the ζ-potential values. In this study, the PZPC(point of zero proton condition) of the particle and collector occurred below a pH of 3.1, H(sup)+ and OH(sup)- acted as a PDI (potential determining ion), and Na(sup)+ acted as an IDI(indifferent ion). The magnitude of the negative ζ-potential values of the particle and collector monotonically increased as the concentrations of Na(sup)+ or Ca(sup)2+([Na(sup)+] or [Ca(sup)2+]) decreased (the values of pNa or pCa increased). In the case of latex particles, the ζ-potential should aproach zero (isoelectric point; IEP) asymptotically as the pNa approaches zero, while in the case of calcium chloride electrolyte, ζ-potential reversal may be expected to occur around 3.16$\times$10(sup)-2MCaCl$_2$(pCa=1.5). pH, valance and ionic strength can be used in various ways to improve the water treatment efficiency by modifying the charge characteristics of the particle and collector. Predictive capability is far less certain when EDL(electrical double layer) repulsive forces exist between the particle and collector.

• 약학회지
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• 제38권3호
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• pp.300-310
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• 1994

Physicochemical properties for the inclusion complex of chenodeoxycholic acid(CDCA) and it's $7{\beta}-hydroxy$ epimer ursodeoxycholic acid(UDCA) with ${\beta}-cyclodextrin({\beta}-CyD)$ were studied. The formation of the complex in the solid state were confimed by polarized microscopy and differential scanning calorimetry(DSC). Proton nuclear magnetic resonance$(^1H-NMR)$spectroscopy showed that CDCA and UDCA form an inclusion complex with ${\beta}-CyD$ in aqueous solution. The 1 : 1 stoichiometry of the complex was dextermined by the continuous variation method. From DSC and $^1H-NMR$ studies, there were not any differences between CDCA and UDCA. Complex of CDCA and UDCA showed increase in solubility and dissolution compared with CDCA and UDCA alone, respectively. Solubility pattern of UDCA complex was pH independent but, CDCA complex was like that of CDCA. Dissolution rate increased markedly in case of UDCA complex compared with CDCA complex, especially in acidic pH value.

• 한국전기전자재료학회논문지
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• 제27권6호
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• pp.394-398
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• 2014

We fabricated the electrolyte-dielectric-metal (EDM) sensor on the base of AAO (anodic aluminum oxide) template with variation of the anodizing temperature. When a surface is immersed or created in an aqueous solution, a discontinuity is formed at the interface where such physicochemical variables as electrical potential and electrolyte concentration change significantly from the aqueous phase to another phase. Because of the different chemical potentials between the two phases, charge separation often occurs at the interfacial region [1]. This interfacial region, togeter with the charged surface, is usually known as the electrical double layer (EDL) [2]. The structural and electrochemical properties of AAO sensor were investigated for applications in capacitive pH sensors. To change the thickness of the AAO template, the anodizing temperature was varied from $5^{\circ}C$ to $20^{\circ}C$, the thickness of the AAO template invreased from 300 nm to 477 nm. The pH sensitivity of sensors with the anodizing temperature of $20^{\circ}C$ showed the highest value of 56.4 mV/pH in the pH range of 3 to 11. The EDM sensor with the anodizing temperature of $20^{\circ}C$ exhibited the best long-term stability of 0.037 mV/h.

• Parasites, Hosts and Diseases
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• 제46권2호
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• pp.77-82
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• 2008

Fishborne zoonotic metacercariae have not been reported from brackish water and marine fish from Vietnam waters although these parasites are common in the country's freshwater fish. Both wild-caught and cultured grouper (Epinephelus coioides and Epinephelus bleekeri), and mullet (Mugil cephalus) from brackish and marine waters located in Khanh Hoa province in central coastal Vietnam were examined, and found positive for zoonotic trematode metacercariae. From grouper, Heterophyopsis continua and Procerovum varium were recovered. The prevalence of H. continua ranged from 2.0 to 6.0% and that for P. varium ranged from 11.6 to 15.8%. Mullet were infected with Pygidiopsis summa and H. continua; both of these species are new records for Vietnam. The prevalence of P. summa in mullet was generally high, ranging from 17.6 to 75.5%, and was significantly higher than the prevalence of H. continua (2.5 to 32.4%). There were no significant differences in the prevalence of metacercariae between grouper from natural or cultured habitats, indicating that the highest risk of infection occurs in the wild-caught state prior to their placement in culture. Further, there was no difference in metacercarial prevalence between the 2 species of grouper. Infected wild-caught seed were only observed from January to October. Monthly variation in prevalence suggests seasonal variation in mullet infections occurs in this region with the highest transmission taking place from October to December. Basic investigations on the ecology and epidemiology of these intestinal flukes need to be carried out to determine their significance as a public health problem and the aspects of their biology that may be vulnerable to control interventions.

• Macromolecular Research
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• 제17권5호
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• pp.307-312
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• 2009

Core-shell hydrogel nanocomposite was fabricated by encapsulating a silica-gold nanoshell (SGNS) with poly(N-isopropylacrylamide-co-acrylic acid) (PNIPAM-co-AAc) copolymer. The oleylamine-functionalized SONS was used as a nanotemplate for the shell-layer growth of hydrogel copolymer. APS (ammonium persulfate) was used as a polymerization initiator to produce a hydrogel-encapsulated SGNS (H-SGNS). The amounts of NIPAM (N-isopropylacrylamide) monomers were optimized to reproduce the hydrogel-encapsulated SGNS. The shell-layer thickness was increased with the increase of polymerization time and no further increase in the shell-layer thickness was clearly observed over 16 h. H-SGNS exhibited the systematic changes of particle size corresponding to the variation of pH and temperature, which was originated from hydrogen-bonding interaction between PNIPAM amide groups and water, as well as electrostatic forces attributed by the ionization of carboxylic groups in acrylic acid.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.266-269
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• 2003

This paper is concerned with a forming analysis of front side members and the application of the forming effect in crash analysis of auto-body. Drawbead restraining forces are calculated with ABAQUS/Strandard in order to identify the boundary condition in forming process. Forming analysis with equivalent drawbead is carried out with LS-DYNA3D. In order to demonstrate the validity of the forming analysis, quantitative comparison of the thickness variation between the real product and the numerical simulation result is carried out. Forming histories obtained from the forming analysis are utilized as the initial condition of the crash analysis for accurate assessment of the crashworthiness.