2015 개정 교육과정 화학 II 교과서의 상평형 그림에 대한 문제점 분석

황영하,백성혜 대한화학회 2023 대한화학회지 Vol.67 No.1

In this study, six types of 2015 revised curriculum ChemistryII textbooks were analyzed for conditions, defini- tions, whether or not critical points were displayed, and real-life examples of phase diagram. In this study, it was confirmed that the problems pointed out in several previous studies were not reflected in the 2015 revised curriculum ChemistryII text- book. The same as the situation defining the phase diagram, the translation of the phase diagram into a phase equilibrium dia- gram, the distinction between phase and state being unclear, the critical point not being shown in the phase diagram, real life examples are very limited what is being presented as is suggested as a problem. Therefore, it is necessary to reflect the results of various previous studies in the revised curriculum ChemistryII textbook that will be made in the future, specify the condi- tions under which the phase diagram is drawn, newly model the situation defining the phase diagram, and translate the phase diagram as a ‘phase diagram’. It is necessary to use the term, clarify the distinction between phase and state, mark the critical point in the phase diagram, and develop various real-life examples 이 연구에서는 2015 개정 교육과정 화학Ⅱ 교과서 6종을 대상으로 상평형 그림의 조건 , 정의 , 임계점의 표시 유무와 실생활 예시 등을 분석하였다 . 본 연구에서는 여러 선행 연구에서 지적한 문제점들이 2015 개정 교육과정 화학Ⅱ 교과서에 반영되고 있지 않음을 확인했으며 , 상평형 그림이 그려지는 조건이 명시되지 않은 것과 , 상평형 그림을 정의하는 상황이 증기압력을정의하는 상황과 동일한 것, phase diagram을 상평형 그림으로 번역한 것, 상(phase)과 상태 (state)의 구분이 불분명한 것, 임계점을 상평형 그림에서 나타내지 않은 것, 실생활 예시를 매우 한정적으로 제시하고 있는 것 등을 문제로 제안하였다 . 따라서 앞으로 이루어질 개정 교육과정 화학Ⅱ 교과서에서는 여러 선행 연구들의 결과를 반영하는 것이 필요하며 , 상평형 그림이 그려지는조건을 명시하고 , 상평형 그림을 정의하는 상황을 새로이 모델링하고 , phase diagram을 상 도표라는 용어로 번역하고 , 상과 상태의 구분을 명확히 하고, 상평형 그림에서 임계점을 표시하며 다양한 실생활 사례를 개발할 필요가 있다

Dynamic Phase Transition and Multicritical Dynamic Phase Diagrams of The Kinetic Spin-2 Ising Model With Repulsive Biquadratic Coupling under a Time-dependent Oscilating External Field

Mustafa Keskin,Mehmet Ertas,Osman Canko 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.4

We calculate the dynamic phase transition (DPT) temperatures and present the dynamic phase diagrams in the kinetic spin-2 Blume-Emery-Griffiths model with repulsive biquadratic coupling under the presence of a time-dependent oscillating external magnetic eld. First, we employ the Glauber transition rates to construct the set of mean-field dynamic equations. Then, we study the time variation of the average order parameters to nd the phase in the system. We also investigate the behavior of the dynamic order parameters to characterize the nature (continuous or discontinu- ous)of the transition and to obtain the DPT points. We present the dynamic phase diagrams in the plane of the reduced temperature versus magnetic field amplitude. The phase diagrams exhibit the ferrimagnetic, ferromagnetic -1, antiquadrupolar and disordered fundamen- tal phases. In addition to these fundamental phases, depending on the interaction parameters, we find ten coexisting or mixed phases composed of binary and ternary combinations of fundamental phases. The phase diagrams also display many special points, such as a dynamic tricritical point, a zero-temperature critical point, a critical end point, a double critical end point, a multicritical point, a triple point and a tetracritical point.

Potts Model with the Simplest Modulated Phase

Nasir Ganikhodjaev,Seyit Temir,Hasan Ak³n,Selman Ugu 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.5

We study the phase diagrams for the Potts model on the Bethe lattice with competing nearest-neighbor interactions J1 and ternary interactions J_p and J_t: A_t vanishing temperature, the phase diagram is fully determined for all values and signs of J_p = J_1 and J_t = J_1; in particular, we show that the phase diagrams contain ferromagnetic, paramagnetic and < 2 > phases only; <i>i.e.</i>, the set of modulated phases consists of the < 2 > phase only for J_1 > 0 and J_p = J_1 < 0: We verify that values of T = J_1 in the very narrow strip -0.11 < T = J_1 < 0 with -J_p = J_1 < 0 favor the modulated phase, which is either a commensurate phase with a very large period or an incommensurate phase. The transition lines are obtained from stability conditions, and characteristic points in the phase diagram are analyzed by using numerical iterations. Also the wavevectors versus temperature are plotted for some critical points in the modulated phases.

Dynamic Phase Transitions in the Kinetic Mixed Spin-1/2 and Spin-1 Ising Ferrimagnetic System under a Time-Dependent Magnetic Field

Mustafa Keskin,Osman Canko,Yasin Polat 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.2

Within a mean-eld approach, the kinetics of a mixed spin-1/2 and spin-1 Ising ferimagnetic system with a crystal-field interaction on a square latice in the presence of a time-dependent oscilatinge xternal magnetic field is studied. We employ the Glauber transition rates to construct the mean-field dynamical equations. The time variations of the average magnetizations and the thermal behavior of the dynamic magnetizations are investigated extensively. The dynamic phase transition points are obtained and the phase diagrams are presented in the reduced temperature (T) and magnetic field amplitude (h) plane. The global phase diagram of this simple mixed spin includes six distinct topologies and one ordered and one mixed phase. The system also displays one or two tricritical points and a rentrant behavior, depending on the values of the interaction parameters. The phase diagrams are also discused in the (d, T) plane, where d is the crystal-field interaction and one interesting phase diagram is presented.

Phase Diagram of a Physisorbed Krypton Monolayer on Graphite Using an Elipsometric Technique

B. I. Choi,H. S. Nham,H. S. Youn 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.6

Vapor presure adsorption of krypton on highly-oriented pyrolytic graphite (HOPG) in the monolayer region has ben studied using a phase-modulated elipsometric technique. The two succesive phase transitions, gas-liquid (or uid)-solid, were observed during build-up of a monolayer and from these, a 2D triple point could be determined. We also observed that as the adsorption amount of an initialy formed 2D solid layer increased, the commensurate - incommensurate structural phase transition progresed. The phase transition from a 2D fluid to a 2D solid was a first order transition, which means that a 2D super-critical fluid can coexist with commensurate solid, which contradicts Berker's theory. Vapor presure adsorption of krypton on highly-oriented pyrolytic graphite (HOPG) in the monolayer region has ben studied using a phase-modulated elipsometric technique. The two succesive phase transitions, gas-liquid (or uid)-solid, were observed during build-up of a monolayer and from these, a 2D triple point could be determined. We also observed that as the adsorption amount of an initialy formed 2D solid layer increased, the commensurate - incommensurate structural phase transition progresed. The phase transition from a 2D fluid to a 2D solid was a first order transition, which means that a 2D super-critical fluid can coexist with commensurate solid, which contradicts Berker's theory.

REBa₂Cu₃O_(7-X) (RE=Nd, Gd, Dy) 초전도체의 열처리에 따른 상변태와 미세구조

오용택,신동찬 조선대학교 생산기술연구소 2003 生産技術硏究 Vol.25 No.2

This study investigated the phase transformation of the REBa₂Cu₃O_(7-x) (RE = Nd, Gd, Dy) superconductor, and CCT (Continuous-Cooling-Transformation) along with the TTT (Time- Temperature-Transformation) diagrams are suggested according to the isothermal and continuous cooling heat-treatments. The peritectic temperature of the RE-123 phases approximately decreased to 30℃ when the ionic radius of the rare-earth elements was reduced. The optimum cooling rate, where BC and Cu-free phases do not exist, was 0.001℃/s. At this cooling rate, the RE-123 phase grew with a c-axis perpendicular to the surface and had a well-distributed RE-211 phase. When the oxygen partial pressure was reduced during isothermal heat-treatment. the formation temperature of the RE-211 phase decreased. In addition, the formation temperature of the RE-123 phases decreased from l000℃ (Nd-123) to 925℃ (Gd-123), and finally 875℃ (Dy-123) according to the decrease in the ionic radius of the rare-earth elements. Compared to Nd-123, Gd- and Dy-123 had a better texture with a well-distributed RE-211 phase.

Rich Phase Separation Behavior of Biomolecules

신용대 한국분자세포생물학회 2022 Molecules and cells Vol.45 No.1

Phase separation is a thermodynamic process leading to the formation of compositionally distinct phases. For the past few years, numerous works have shown that biomolecular phase separation serves as biogenesis mechanisms of diverse intracellular condensates, and aberrant phase transitions are associated with disease states such as neurodegenerative diseases and cancers. Condensates exhibit rich phase behaviors including multiphase internal structuring, noise buffering, and compositional tunability. Recent studies have begun to uncover how a network of intermolecular interactions can give rise to various biophysical features of condensates. Here, we review phase behaviors of biomolecules, particularly with regard to regular solution models of binary and ternary mixtures. We discuss how these theoretical frameworks explain many aspects of the assembly, composition, and miscibility of diverse biomolecular phases, and highlight how a model-based approach can help elucidate the detailed thermodynamic principle for multicomponent intracellular phase separation.

REBa₂Cu₃O_7-x (RE=Nd, Gd, Dy) 초전도체의 열처리에 따른 상변태와 미세구조

오용택,한용희,한병성,한상철,성태현,홍광준,신동찬 한국전기전자재료학회 2003 전기전자재료학회논문지 Vol.16 No.12

This study investigated the phase transformation of the REBa$_2$Cu$_3$$O_{7-x}$ (RE=Nd, Gd, Dy) superconductor, and CCT (Continuous-Cooling-Transformation) along with the TTT (Time-Temperature-Transformation) diagrams are suggested according to the isothermal and continuous cooling heat-treatments. The peritectic temperature of the 123 phases decreased approximately 3$0^{\circ}C$ when the ionic radius of the rare-earth elements was reduced. The optimum cooling rate where BC and Cu-free phases do not exist was 0.001$^{\circ}C$/s. At this cooling late, the 123 phase grew with a c-axis Perpendicular to the surface and had a well-distributed 211 phase. When the oxygen partial pressure was reduced Outing isothermal heat-treatment, the formation temperature of the 211 phase decreased. In addition, the formation temperature of the 123 phases decreased from 100$0^{\circ}C$ (Nd-123) to 9$25^{\circ}C$ (Gd-123), and finally 875$^{\circ}C$ (Dy-123) according to the decrease in the ionic radius of the tare-earth elements. Compared to Nd-123, Gd- and Dy-123 had a better texture with a well-distributed 211 phase.e.

성담 송환기『태극도설』해석의 우주론적 의의

이종성 ( Jong-sung Lee ) 한국공자학회 2015 공자학 Vol.29 No.-

이 논고는 성담 송환기의 역학사상에 초점을 맞추고, 특히 성담 송환기가 지향하고자 한 철학적 의의를 우주론적 방면에서 구명하고자 한 의의가 있다. 이 글의 논의 대상은 『태극도설』에 대한 성담의 역학적 관점이다. 그 논의자료는 성담 송환기가 자신의 문인이던 남치태에게 보낸 서간문 한 편에 제한된다. 그럼에도 이 서간문에는 『태극도설』에 대한 성담의 입장이 명시적으로 드러나 있기 때문에 제한된 양에 비하여 그 철학적 의의는 자못 크다. 성담은 『태극도설』의 문제를 크게 우주론적 문제와 인간학적문제로 나누어 살펴본 특징이 있다. 이 글은 논의의 방편 상 전자에 대해서 주목한 것이다. 이 글은 다음과 같은 세 가지 내용을 다룬다. (1)『태극도설』의 첫 번째 주제이기도 한 무극과 태극의 관계이다. 성담은 무극과 태극이 별개의 존재가 아니라고 보고, 그발생론적 전개의 과정을 통해 우주론적 의의에 관해 구명한 특징이 있다. (2) 음양의 움직임과 고요함의 문제이다. 성담은 음양이 ‘성(誠)’의 원리에 의하여 전개되는데, 움직임은 양에 속하고 고요함은 음에 속한다고 본다. 음양의 움직임과 고요함에 의하여 만물의 변화가 일어난다. 다만 음양의 움직임과 고요함은 상호 보완적인 관계에 있다. (3) 성담은 오행생성의 전개방식에 세 가지가 있다고 본다. 그하나는 수열을 통해 보는 것으로 ‘수-화-목-금-토’의 순서이다. 두 번째는 오행상생을 통해 보는 것으로 ‘목-화-토-금-수’의 순서이다. 세 번째는 오행의 형질을 통해 보는 것으로 ‘금-목-수-화-토’의 순서이다. 이상의 내용이 성담이 본 『태극도설』에 대한 우주론적 해석의내용이다. 성담은 철저히 주자학의 사유방식 안에서 『태극도설』을 해석함으로써, 자신의 학문적 근거가 주자학에 있음을 대내외적으로 천명한다. 요컨대 성담의 『태극도설』에 대한 우주론적 해석의 입장은 철저히 주자학적인 특징을 갖는다는 점에 그 의의가 있다. This paper studied the philosophy of Song, Hwan-Gi(宋煥箕) in terms of cosmology, looking at the Yi(易) of Song, Hwan-Gi. This paper investigated the perspective of Song Hwangi on the Diagram of the Superme Ultimate through the letter which is sent to his disciple Nam, Chi-Tae(南致泰). This letter is the only available source today. However, This short letter contains the clear interpretation on the Diagram of the Superme Ultimate. Therefore the value of this letter should not be underestimated. Song, Hwan-Gi divided and studied the Diagram of the Superme Ultimate into the cosmological and human matter. This paper focused on the cosmological interpretation by Song, Hwan-Gi of the Diagram of the Superme Ultimate. This paper contains the next followings: 1) the relationship of Wuji(無極) and Taiji(太極), which is the most important subject of the Diagram of the Superme Ultimate. He did not think that Wuji(無極) and Taiji(太 極) are different existence, and investigated the cosmological aspect; 2) the matter of Yinyang(陰陽). He thought Yinyang follows the principle of Cheng(誠), and movement is the character of Yang and the tranquility is the character of Yin. Yin and Yang are interdependent; 3) He divided the types of change of Five Phases into three. The sequence of the first type is Water(水)-Fire (火)-Wood(木)-Metal(金)-Earth(土), in terms of symbolic number. The sequence of the second type is Wood(木)-Fire(火)-Earth (土)-Metal(金)-Water(水), in terms of the Yellow River Chart. The sequence of the third type is Metal(金)-Wood(木)-Water(水)-Fire (火)-Earth(土), in terms of character of Five Phases. Song, Hwan-Gi showed his study originated from Zhuzi by interpreting the Diagram of the Diagram of the Superme Ultimate based on the study of Zhuzi. In a word, his standpoint on the matter of cosmological interpretation has completely followed Zhuzi’s.

Phase Stability Diagrams of Ti–M–O–C (M = Zr, Hf, Nb, and Ta) Systems at 1800 K

권한중,Ahram Moon,Jiwoong Kim 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.2

Phase stability diagrams of Ti–M–O–C (M = Zr, Hf, Nb, and Ta) systems at 1800 K were constructed as a function of thecarbon activity, oxygen partial pressure, and solution formation characteristics, in order to determine the optimum conditionsfor the formation of (Ti0.75M0.25)C via carbothermal reduction of oxide mixtures. The tendency to form (Ti0.75M0.25)Cwas predicted on the basis of the standard Gibbs free energies of formation (ΔG◦f) of (Ti0.75M0.25)C solid-solution carbides,calculated by first-principles simulations. It was concluded that at 1800 K, the (Ti0.75Nb0.25)C and (Ti0.75Ta0.25)C phases aremore stable than the TiC–NbC and TiC–TaC mixtures, whereas the (Ti0.75Zr0.25)C and (Ti0.75Hf0.25)C phases are less stablethan the corresponding TiC–ZrC and TiC–HfC mixtures. The phase stability diagrams of the Ti–M–O–C systems were thendrawn using the calculated ΔG◦f values and used to predict the tendencies to form solid-solution phases. The validity of thetheoretical predictions was then verified using experimental results.