• 한국전기전자재료학회논문지
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• 제14권6호
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• pp.475-480
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• 2001

Glasses in he system CuO-P$_2$O$_{5}$ -Nb$_2$O$_{5}$ -Nb$_2$O$_{5}$ -V$_2$O$_{5}$ were prepared by a press-quenching method on the copper plate. the glass-ceramics from these glasses were obtained by post-heat treatment, and the crystallization behavior and DC conductivities were determined. The conductivities of the glasses were range from 10$^{-6}$ s.$cm^{-1}$ / at room temperature ,but the conductivities of the glass-ceramics were 10$^{-3}$ s.$cm^{-1}$ / increased by 10$^3$ order. The crystalline product in the glass-ceramics was CuV$_2$O$_{6}$ . the crystal growth of CuV$_2$O$_{6}$ phase increased with heat-treatment conditions. The linear relationship between il($\sigma$T) and T$^{-1}$ suggested that the electrical conduction in the present glass-ceramics would be due to a small polaron hopping(SPH) mechanism.

• 한국식품과학회지
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• 제9권2호
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• pp.138-143
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• 1977

메밀 전분의 이화학적 성질을 살펴본바, 입자의 크기는 4.3-11.4 미크론(평균 7.8미크론)이었다. 전분의 물결합능력은 103.7%, 아밀로스 함량은 25%이었다. 복굴절성 소실의 측정법에 의한 호화개시 및 호화 종료 온도는 각각 $61^{\circ}$ 및 $65^{\circ}C$이었고 아밀로그라프에 의한 초기 호화온도는$64.5^{\circ}C$이었다. 전분의 노화속도는 $21^{\circ}C$에서 밀 전분보다 다소 빨랐다.

• 한국재료학회지
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• 제14권7호
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• pp.477-481
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• 2004

High quality polycrystalline silicon is very critical part of the high quality thin film transistor(TFT) for display devices. Metal induced lateral crystallization(MILC) is one of the most successful technologies to crystallize the amorphous silicon at low temperature(below $550^{\circ}C$) and uses conventional and large glass substrate. In this study, we observed that the MILC behavior changed with abrupt variation of the amorphous silicon active pattern width. We explained these phenomena with the novel MILC mechanism model. The 10 nm thick Ni layers were deposited on the glass substrate having various amorphous silicon patterns. Then, we annealed the sample at $550^{\circ}C$ with rapid thermal annealing(RTA) apparatus and measured the crystallized length by optical microscope. When MILC progress from narrow-width-area(the width was $w_2$) to wide-width-area(the width was $w_1$), the MILC rate decreased dramatically and was not changed for several hours(incubation time). Also the incubation time increased as the ratio, $w_1/w_2$, get larger. We can explain these phenomena with the tensile stress that was caused by volume shrinkage due to the phase transformation from amorphous silicon to crystalline silicon.

• 소성∙가공
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• 제15권3호
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• pp.213-219
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• 2006

To improve the strength of glass is being studied in order to contribute to weight saving of flat panel displays. Generally, the strength achieved of glass-ceramics is higher as is the fracture toughness by the formation of a heterogeneous phase inside glass. In this study, Ag-doped $45SiO_2-24CaO-24Na_2O-4P_2O_5\;and\;70SiO_2-10CaO-24Na_2O-10TiO_2$ glasses were irradiated to strengthen by crystallization using femto-second laser pulse. XRD, Nano-indenter and SEM etc., irradiation of laser pulse without heat-treated samples was analyzed. Samples irradiated by laser had higher value($4.4{\sim}4.56^*10-3Pa$) of elastic modulus which related with strength of glass than values heat-treated samples and these are $1.2{\sim}1.5$ times higher values than them of mother glass. This process can be applicable to the strengthening of thinner glass plate, and it has an advantage over traditional heat-treatment and ion-exchange method.

• 한국세라믹학회지
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• 제17권1호
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• pp.20-26
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• 1980

The crystallization behaviors of slag-based glass in $CaO-MgO-Al_2O_3-SiO_2(-Na_2O)$ system have been studied. The mother glass containing 16.50 CaO, 7.50MgO, 19.70Al2O3, 50.80SiO3 and 2.09wt% $Na_2O$ was prepared by using Korean domestic raw materials such as granulated slag, serpentine, sea sand and etc. The glass-ceramics composed of major crystalline phase diopside was produced by the heat treatment in a temperature range from 850$^{\circ}$ to 9$25^{\circ}C$ for 0-6hr. The composition and morphology of diopside phase formed in the system were examined by X-ray diffraction analysis and electron microscopy. The kinetic measurements such as J.M. A plot and Arrhenius plot indicated that the process of nucleation of the initially formed diopside phase could be described from the view point of instantaneous nucleation. It was also demonstrated that the linear crystal growth of diopside phase was proceeded by short range diffusion of $Mg^{2+}$ and $Ca^{2+}$ ion. The microstructures of the resulting glass-ceramics were consisted of leafroidal shaped crystalline aggregations.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.934-937
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• 2003

Glasses in the system $CuO-P_2O_5-V_2O_5$ were prepared by a press-quenching method on the copper plate. The glass-ceramics from these glasses were obtained by post-heat treatment, and the crystallization behavior and DC conductivities were determined. The conductivities of the glasses were range from $10^{-6}s.Cm^{-1}$ at room temperature, but the conductivities of the glass-ceramics were $10^{-3}s.Cm^{-1}$ increased by $10^3$ order. The crystalline product in the glass-ceramics was $CuV_2O_6$. Heat-treatment conditions influenced the crystal growth of $CuV_2O_6$ and conductivity. The linear relationship between in (${\sigma}T$) and $T^{-1}$ suggested that the electrical conduction in the present glass-ceramics would be due to a small polaron hopping(SPH) mechanism.

• 한국세라믹학회지
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• 제21권4호
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• pp.349-354
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• 1984

The purpose of present study is to find the structure crystallization mechanism and physical properties in $TiO_2$ containing lead zinc borosilicate glass system. The experiments such as differential thermal analysis infrared spectral analysis. X-ray diffraction analysis and thermal expansion measurements have been done. Differential thermal analysis of coarse and fine glass powder showed bulk nucleating mechanism for high $TiO_2$ containing glasses and surface nucleation mechanism for low $TiO_2$ containing glasses. The prepared glasses crystallized to crystalline mixture of PbO.2ZnO. $B_2O_3$ .4PbO.2ZnO.$5B_2O_3$and 2PbO.ZnO.$B_2O_3$ when heat-treated in the range of 480 and 51$0^{\circ}C$ and crystallized to PbTiO3 when heat-treated at $600^{\circ}C$. Obtained crystalline phase of $PbTiO_3$ in glass matrix strongly affects to thermal expansion coefficient and the value of crystallized glass varied 68.0 to $107.1{\times}10-7$/$^{\circ}C$ depending on the amount of $TiO_2$added. Infrared spectral analysis showed that [$BO_3$] triangle and [$BO_3$] tetrahedral units were coexisted in the glass with high content of PbO.

• Korean Chemical Engineering Research
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• 제55권2호
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• pp.180-189
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• 2017

난용성 약물의 용해도를 증가시키고 안정성을 향상하기 위한 제약 공결정은, 미국 FDA가 지난 2016년 8월에 공결정을 solvate의 특별한 경우라고 정의를 수정하면서, 개량신약의 개발에 더욱 박차를 가할 것으로 추측된다. 본 연구에서는 모델 조합으로 잘 알려진 indomethacin-saccharin 공결정을 반용매 방법으로 제조할 때, 인라인 모니터링 기법을 적용하여, 반용매의 주입속도에 따른 indomethacin 준 안정상의 일시적인 생성 및 indomethacin-saccharin 공결정의 생성을 관찰하고 메커니즘을 제안하고자 하였다. 그간 인라인 모니터링을 위해서 매우 다양한 분석도구가 연구되어 왔는데, 본 연구에서는 PVM (particle vision measurement)와 FBRM (focused beam reflectance measurement)를 조합하여 공결정화 공정에서의 변화를 실시간으로 측정하였다. 공결정화 결과물의 오프라인 분석은 PXRD (powder x-ray diffraction)와 DSC (Differential scanning calorimeter)를 이용하여 수행하였다. 반용매의 주입 속도에 따라서 공결정이 생성되는 경로에 분명한 차이가 있음을 관찰하였으며, 이러한 상관 관계의 이해를 통해서 제약학적 특성이 더욱 일정하고 품질이 보증된 indomethacin-saccharin Co-crystal을 얻는 조건을 확립하였다. 본 연구결과, PVM과 FBRM을 조합한 인라인 모니터링은 제약 공결정 제조공정에서 활용성이 매우 높은 기술이라고 할 수 있다.

• 태양에너지
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• 제19권2호
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• pp.57-65
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• 1999

[ $H_2O$ ]-NaCl혼합물을 냉축열재로 선택하였으며, 이 혼합물의 상변화온도를 몰농도 변화에 의하여 조절하였다. 그리고 고농도와 저농도의 NaCl과 $H_2O$가 ion-dipole interaction으로 결합하는 구조를 그림으로 가시화하고 가열, 냉각과정에서 $H_2O$-NaCl이 동결, 융해하는 현상을 도시하므로서 융해와 동결과정에서 상변화온도가 2단계로 나타나는 구조적 원인을 구명하였으며, NaCl의 농도변화에 따른 상변화온도를 이론적으로 분석하므로서 실험 및 이론분석 결과의 타당성을 증명할 수 있도록 하였다.

• Biodesign
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• 제6권4호
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• pp.100-102
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• 2018

Autophagy is a degradation pathway that targets many cellular components and plays a particularly important role in protein degradation and recycling. This process is very complex and several proteins participate in this process. One of them, P62/SQSTM1, is related to the N-end rule and induces protein degradation through autophagy. The P62/SQSTM1 makes a huge oligomer, and this oligomerization is known to play an important role in its mechanism. This oligomerization takes two steps. First, the PB1 domain of P62/SQSTM1 makes the base oligomer, and then, when the ligand binds to the ZZ domain of P62/SQSTM1, it induces a higher oligomer by the disulfide bond of the two cysteines. To understand the oligomerization mechanism of P62/SQSTM1, we need to know the dimerization of the PB1 domain. In this study, crystals of PB1 dimer were made and the crystals were diffracted by X-ray to collect usable data up to 3.2A. We are analyzing the structure using the molecular replacement (MR) method.