• Title/Summary/Keyword: Multicomponent

Search Result 248, Processing Time 0.026 seconds

Molecular Layer Deposition of Organic/Inorganic Nanohybrid Dielectrics for OTFTs

  • Lee, Byeong-Hun;Lee, Gwang-Hyeon;Im, Seong-Il;Seong, Myeong-Mo
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.02a
    • /
    • pp.56-56
    • /
    • 2010
  • We report a low-temperature fabrication of organic/inorganic nanohybrid dielectrics for organic thin film transistors. The self-assembled organic layers (SAOLs) were grown by repeated sequential adsorptions of C=C-terminated alkylsilane and metal (Al or Ti) hydroxyl with ozone activation, which was called "molecular layer deposition (MLD)". The $TiO_2$ and $Al_2O_3$ inorganic layers were grown by ALD, which relies on sequential saturated surface reactions resulting in the formation of a monolayer in each sequence and is a potentially powerful method for preparing high quality multicomponent superlattices. The MLD method combined with ALD (MLD-ALD) was applied to fabricate SAOLs-$Al_2O_3$-SAOLs-$TiO_2$ nanohybrid superlattices on polymer substrates at relatively low temperature. The MLD method is an ideal fabrication technique for various flexible electronic devices.

  • PDF

Optical & Structural Properties of multicomponent fiber fabricated by double crucible method (이중도가니법에 의해 제조된 다성분계 화이버의 광학적ㆍ구조적 특성)

  • 오영석;이회관;이용수;강원호
    • Proceedings of the KAIS Fall Conference
    • /
    • 2001.11a
    • /
    • pp.153-156
    • /
    • 2001
  • 광전자 기술의 발전 및 광 응용 분야의 확대에 따라 광전송치의 개발이 필수적이다. 이에 본 연구에서는 보다 넓은 영역의 광을 투과시키고, UV/VIS/NIR의 파장 영역에서 낮은 광 손실을 갖는 fiber를 제조하기 위하여 SiO₂,PbO를 주성분으로 하고 K₂O, Na₂O, B₂O₃등의 산화물을 적량 배합함으로써 core/clad유리의 제조 및 제조된 유리의 물성을 측정하였다. Core/clad의 match를 고려하여 최적조성을 선정하였으며, 이중도가니법을 이용하여 fiber를 제조하였다. 또한, 제조된 fiber의 구조적 특성을 관찰하였으며, 성형시 조건에 따라 50-200㎛의 직경을 갖는 fiber를 제조할 수 있었다. Fiber의 optical loss는 0.3-1.8㎛에서 측정하였다.

Approximate Nonrandom Two-Fluid Lattice-Hole Theory. General Derivation and Description of Pure Fluids

  • 유기풍;신훈용;이철수
    • Bulletin of the Korean Chemical Society
    • /
    • v.18 no.9
    • /
    • pp.965-972
    • /
    • 1997
  • An approximate molecular theory of classical fluids based on the nonrandom lattice statistical-mechanical theory is presented. To obtain configurational Helmholtz free energy and equation of state (EOS), the lattice-hole theory of the Guggenheim combinatorics is approximated by introducing the nonrandom two-fluid theory. The approximate nature in the derivation makes the model possible to unify the classical lattice-hole theory and to describe correctly the configurational properties of real fluids including macromolecules. The theory requires only two molecular parameters for a pure fluid. Results obtained to date have demonstrated that the model correlates quantitatively the first- and second-order thermodynamic properties of real fluids. The basic simplicity of the model can readily be generalized to multicomponent systems. The model is especially relevant to (multi) phase equilibria of systems containing molecularly complex species.

The Emerging Role of Fast MR Techniques in Traumatic Brain Injury

  • Yoo, Roh-Eul;Choi, Seung Hong
    • Investigative Magnetic Resonance Imaging
    • /
    • v.25 no.2
    • /
    • pp.76-80
    • /
    • 2021
  • Post-concussion syndrome (PCS) following mild traumatic brain injury (mTBI) is a major factor that contributes to the increased socioeconomic burden caused by TBI. Myelin loss has been implicated in the development of PCS following mTBI. Diffusion tensor imaging (DTI), a traditional imaging modality for the evaluation of axonal and myelin integrity in mTBI, has intrinsic limitations, including its lack of specificity and its time-consuming and labor-intensive post-processing analysis. More recently, various fast MR techniques based on multicomponent relaxometry (MCR), including QRAPMASTER, mcDESPOT, and MDME sequences, have been developed. These MCR-based sequences can provide myelin water fraction/myelin volume fraction, a quantitative parameter more specific to myelin, which might serve as a surrogate marker of myelin volume, in a clinically feasible time. In this review, we summarize the clinical application of the MCR-based fast MR techniques in mTBI patients.

Sex-Gender Differences in Irritable Bowel Syndrome

  • Kim, Young Sun;Kim, Nayoung
    • Journal of Neurogastroenterology and Motility
    • /
    • v.24 no.4
    • /
    • pp.544-558
    • /
    • 2018
  • Because of the sex-gender differences that are shown in a diversity of physiological and psychological factors, it can be speculated that the clinical presentation of symptoms as well as treatment strategies in women and men with irritable bowel syndrome (IBS) may differ. Studies have revealed that IBS is more common in women than men. As for the IBS subtype, IBS with constipation is significantly more prevalent among women than men. Sex hormones and gender differences may play important roles in the pathophysiology of IBS. However, its pathophysiologic mechanisms still remain largely unknown, and therapeutic implications are limited. Moreover, women IBS patients have been reported to feel more fatigue, depression, anxiety, and lower quality of life than men IBS patients. Furthermore, there has been evidence of differences in the appropriate treatment efficacy to IBS in men and women, although relatively few men are enrolled in most relevant clinical trials. A more sex-gender-oriented approach in the medical care setting could improve understanding of heterogeneous patients suffering from IBS. An individualized and multicomponent approach including sex and gender issues might help improve the treatment of IBS.

Topological Analysis on the Modulus and Network Structure of Miscible Polymer Blends

  • 손정모;박형석
    • Bulletin of the Korean Chemical Society
    • /
    • v.16 no.2
    • /
    • pp.169-180
    • /
    • 1995
  • A topological theory is introduced to extend Tsenoglou's theory to polymer blends having temporary and permanent networks composed of multicomponent polymers which have miscible and flexible chains. The topological theory may estimate the values of free elastic energy, the molecular weight between entanglements, and the equilibrium shear moduli, and it may establish more correctly the topological relations among these physical quantities. Through such introduction of the topological theory, there can be topologically analyzed the mixing law for the rubbery plateau modulus of a fluid polymer blend, and there can be considered the topological relationship to the equilibrium modulus of an interpenetrating polymer network containing trapped entanglements and dangling segments. The theoretically predictive values are compared and show good agreement with the experimental data for several miscible polymer blends.

Rich Phase Separation Behavior of Biomolecules

  • Shin, Yongdae
    • Molecules and Cells
    • /
    • v.45 no.1
    • /
    • pp.6-15
    • /
    • 2022
  • 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.

A Review of Combination Effects and Adverse Effects of Yerba Mate (Ilex paraguariensis) on the Treatment of Obesity (비만치료를 목적으로 마테(Yerba Mate, Ilex paraguariensis)를 함유한 복합투여물의 효과 및 부작용에 대한 고찰)

  • Ahn, Jae Hyun;Lee, Min Ho;Lee, Seung Hoon;Choi, Do Young;Lee, Jae Dong
    • Journal of Acupuncture Research
    • /
    • v.33 no.2
    • /
    • pp.135-150
    • /
    • 2016
  • Objectives : The aim of this study is to review the combination effects and adverse effects of Yerba Mate (Ilex paraguariensis) on the treatment of obesity. Methods : Four databases were searched, including Pubmed, National assembly library, RISS4u, and NDSL, for studies published before March 31, 2016 using the keywords 'yerba mate', 'Ilex paraguariensis', and those related to 'obesity'. Clinical trials, and both in vivo and in vitro studies were classified according to the following categories: publication year, nationality, types and composition of test compounds, combination effects, adverse effects, and safety. Results : A total of 16 articles (14 clinical trials, one in vivo, one in vitro) were included in the analysis. Combination effects were reported from six YGD (Yerba Mate, Guarana, Damiana, Zotrim), five Meltdown, one Shred-matrix, one DBX (DymaBurn Xtreme), one XSIII research study, and adverse effects were reported from two YGD (Zotrim), four Meltdown, one Shred-matrix and one MetEF research study. YGD and Shred-matrix increased satiety while YGD and MetEF had adverse gastrointestinal effects potentially due to guarana. Meltdown and Shred-matrix increased energy expenditure and fat oxidation and had the adverse effects of increased heart rate and blood pressure due to the thermogenic effect of caffeine and yohimbine. DBX increased resting energy expenditure but no difference was observed in respiratory exchange ratio. XSIII reduced body weight gain and food intake more than each of the extracts did on their own. Conclusion : Taken together, the combination effects and adverse effects differed according to the composition of test compounds and the ratio of ingredients. Multicomponent approaches should be used for treating multifactorial diseases such as obesity. As a general conclusion, there is a place for a combination of herbal components including yerba mate, based on the principle of Kun-Shin-Choa-Sa for the treatment of obesity.

Measurement and Analysis on the Physical Properties of Multi Lithium Salts Solution in Absorption Heat-Pumps (흡수식냉난방기용 다성분 리튬염 작동매체의 증기압 및 용해도 측정)

  • Ju, Woo-Sung;Kim, Hee-Taik;Oh, Young-Sam;Baek, Young-Soon
    • Applied Chemistry for Engineering
    • /
    • v.9 no.1
    • /
    • pp.82-88
    • /
    • 1998
  • In an effort to obtain high efficiency in air cooled absorption heat pump, a new working fluid has developed with the addition of $LiNO_3$ and LiCl to the conventional solution of $LiBr-H_2O$. The solubility and vapor pressure of the multicomponent salts solution developed in this work were measured and compared with the results of $LiBr-H_2O$ solution. It was observed that there exists an optimal molar ratio of the inorganic salts in terms of solubility. The molar ratio of LiBr, $LiNO_3$ and LiCl was found to be about 5:1 in the $LiBr-LiNO_3$ mixture, and in the case of $LiBr-LiNO_3-LiCl$ mixture, the molar ratio of LiBr, $LiNO_3$ and LiCl was found to be around 5:1:2. The vapor pressure of the multicomponent salts solution of the optimal molar ratio was increased with adding $LiNO_3$, while decreased with adding LiCl.

  • PDF

Characteristics of Thermoluminescence and Electron Spin Resonance and Organoleptic Quality of Irradiated Raisin and Dried Banana During Storage (건포도와 건바나나의 감마선 조사와 저장기간에 따른 열발광 및 전자스핀공명 특성과 관능적 품질)

  • Jo, Deok-Jo;Kwon, Joong-Ho
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.31 no.4
    • /
    • pp.609-614
    • /
    • 2002
  • The characteristics of thermoluminescence (TL) and electron spin resonance (ESR) and organoleptic qualities of gamma-irradiated raisin and dried banana were investigated during storage at 4$^{\circ}C$ for 6 months. The minerals separated from non-irradiated raisins showed TL glow curve (TL$_1$) with very low intensity around 200~30$0^{\circ}C$, while the irradiated samples at 1 kGy or more showed glow curves with higher intensity around 18$0^{\circ}C$, with linear increase by irradiation dose ($R^2$=0.9684), which made it possible to identify irradiated samples during 6 months. Moreover, TL ratios (TL$_1$/TL$_2$) through the reirradiation step at 1 kGy enhanced confidence in the identification of irradiated raisins. The ESR signals of multicomponent lines resulted from crystalline sugar radicals were shown in irradiated banana, identifying irradiated samples. The ESR signal intensity was dependent on irradiation doses ($R^2$=0.8977) and the signals were stable enough to be detected by 6th month after storage. Considering tile marketability of irradiated dried fruits during 6 months at low temperature TL and ESR analyses were shown suitable for the identification of irradiated raisins and dried banana, respectively.