462 research outputs found
Phase Equilibrium Calculations by Equation of State v2
Practical methods for phase equilibrium calculations by the equation of state for a perfect solid and liquid (v2) are described using examples of worksheets. Using the Microsoft Excel worksheets, the pressure, Gibbs energy and other thermodynamic quantities of a molecular system are obtained as functions of temperature and volume. Some examples of VBA (Visual Basic for Applications) programs are given to obtain volume and other thermodynamic properties as a function of temperature under a given pressure. The thermodynamic consistency test is performed as a function of temperature at a given pressure, where the difference between the heat capacity under a constant pressure and that under a constant volume should equal to an expression consisting of the thermal expansion coefficient, temperature, volume and isothermal compressibility.完全固体・完全液体の状態方程式に基づいて、相転移を計算する方法を示した。エクセルのワークシートを使って、ギブズエネルギーやその他の熱力学量を温度と体積の関数として得ることができる。VBAプログラムの例も添付した。熱力学的な恒等式を用いて、数値計算に大きな矛盾がないことを確かめた
Numerical Calculations in Phase Equilibrium by Equation of State v3
A practical method for phase equilibrium calculations using the equation of state for a perfect solid and a perfect liquid is shown along with examples of Excel worksheets. The molecular systems of a perfect solid and a perfect liquid are assumed to be composed of single-type spherical molecules. The molecular interaction is expressed by a Lennard-Jones potential function. The pressure and internal energy of the system are expressed as functions of temperature and volume. Other thermodynamic functions such as entropy are also given as functions of temperature and volume. A thermodynamic constancy test is performed.完全固体・完全液体の状態方程式 v3に基づいて、相転移を計算する方法を示した。エクセルのワークシートを使って、ギブズエネルギーやその他の熱力学量を温度と体積の関数として得ることができる。VBAプログラムの例も添付した。熱力学的な恒等式を用いて、数値計算に大きな矛盾がないことを確かめた
Perfect Solid and Liquid
A 3-phase equilibrium in argon is obtained by the thermodynamics of the perfect solid and liquid. The equation of state (EOS) for a perfect solid is obtained for a pure substance of spherical molecules that undergo molecular interaction of the Lennard-Jones form. The primitive internal energy EOS for a perfect solid (referred to as v0 EOS) is the sum of the thermally averaged kinetic energy and the potential energy of the nearest neighbors in a face-centered cubic (FCC) solid at 0 K. The extended internal energy EOS for a perfect solid (v1) includes a long-range effect in the low density region as the internal energy in the van der Waals EOS. The pressure EOS is written as the volume derivative of the potential energy at 0 K to satisfy the EOS with respect to thermodynamics. The temperature effect in the virial term is included in the extended pressure EOS. The EOS for a perfect liquid is the van der Waals EOS with empirical coefficients to explain the 3-phase equilibrium. The change in entropy for a reversible process is calculated by the standard method. The thermodynamic quantities of each phase are written as functions of volume and temperature. In this way, the Gibbs energy per molecule is plotted as a function of pressure for both solid and liquid phases, and the crossing point in the plot is the phase transition point. The p-V-T relations on the equilibrium lines are comparable with the experimental and molecular simulation results. The calculated average potential energy and entropy on the phase boundaries are consistent with the simulations. The thermodynamic quantities under a low pressure are compared with the molecular dynamic simulations. The quantities examined are volume, internal energy, enthalpy, entropy, Helmholtz energy, Gibbs energy, expansion coefficient, isothermal compressibility and heat capacity under a constant pressure.固体についてレナードージョーンズ相互作用と面心立方格子を仮定して、簡単化した状態方程式を示した。これを完全固体の状態方程式と呼ぶ。液体と気体については実験値の解析から得られたファンデルワールス状態方程式を仮定した。これを完全液体の状態方程式と呼ぶ。これらを用いて球形分子系の3相平衡をギブズエネルギーの計算から導いた。その結果をアルゴン系についての実験結果および、モンテカルロ法・分子動力学法シミュレーションと比較して、全体的に良い対応関係を得た
親密確認活動におけるおそろい行動 : 被異質視不安と自尊感情との関連
本研究は青年期女子の友人関係における被異質視不安・異質拒否傾向,自尊感情と「おそろい行動」の関連を明らかにすることを目的とし研究を行った。ここで指す「おそろい」とは,洋服や文具などを友人間で合わせることを意味する。私立女子大学1 年生286名(M=18.4,SD=.75)を対象に質問紙調査を行った。その結果,(1)自尊感情が高いほど被異質視不安は低くなり,(2)被異質視不安が高いほど「おそろい行動」に対して肯定的な感情を持つことが明らかになった。また青年期女子の友人関係において被異質視不安と異質拒否傾向は異なって影響していることが推測された。This study examined the relation of the anxieties of adolescents over being regarded as different from others and their tendency toward uniformity in their friendship groups with self-esteem and the behavior of osoroi. Osoroi refers to friends who have matching clothes and stationary or another accessory or item. The subjects were university freshman at a private women's college (N = 286). The major findings were follows. (1) Anxiety over being regarded as different was found to be related to self-esteem. (2) Self-esteem was associated with anxiety over being regarded as different and the feeling of osoroi. The results show that the tendency toward uniformity in friendship groups affect friendships differently
青年期女子におけるおそろい行動 : 被異質視不安及び異質拒否傾向・適応感との関連
This study examined the relationship between adolescent anxiety about being seen as different from others and the tendency toward friendship group uniformity, subjective adjustment, and“ osoroi” behavior, which is when friends have matching clothes, stationery, and other paraphernalia. The subjects were junior high and high school students at a private women’s school. The findings were as follows: (1) adolescent anxiety over being seen as different from others and the tendency toward friendship group uniformity were related to a sense of solidarity, and (2) few demonstrated “osoroi” behavior. It was also found that “osoroi” was related to an outsider’s perspective
Prevention of Image Quality Degradation in Wider Field Optical Coherence Tomography Angiography Images Via Image Averaging
Purpose: To evaluate the mutual effect of widening the field of view and multiple en face image averaging on the quality of optical coherence tomography angiography (OCTA) images. Methods: This prospective, observational, cross-sectional case series included 20 eyes of 20 healthy volunteers with no history of ocular or systemic disease. OCTA imaging of a 3 × 3-mm, 6 × 6-mm, and 12 × 12-mm area centered on the fovea was performed nine times using the PLEX Elite 9000. We acquired averaged OCTA images generated from nine en face OCTA images. The corresponding areas in the three scan sizes were evaluated for the original single-scanned OCTA images and averaged OCTA images both qualitatively and quantitatively. Quantitative measurements included vessel density (VD), vessel length density (VLD), fractal dimension (FD), and contrast-to-noise ratio (CNR). Results: Significant differences in VD, VLD, FD, and CNR (P < 0.001) were observed due to the mutual effect of averaging and differences in scan size. Both qualitative and quantitative evaluations indicated that the quality of 6 × 6-mm averaged images was equal to or better than that of 3 × 3-mm single-scanned images. However, the quality of 12 × 12-mm averaged images did not reach that of 3 × 3-mm single-scanned images. Conclusions: To some extent, multiple en face OCTA image averaging can compensate for the deterioration in image quality caused by widening the field of view. Translational Relevance: Multiple en face OCTA image averaging can be a technique for acquiring wider field OCTA images with good quality
Is oral food challenge useful to avoid complete elimination in Japanese patients diagnosed with or suspected of having IgE-dependent hen's egg allergy? A systematic review
Background: IgE-mediated egg allergy is a common food allergy worldwide. Patients with egg allergy are known to easily achieve tolerance compared to other allergens such as nuts. Oral food challenge (OFC) is often performed on patients diagnosed with or suspected of having IgE-mediated food allergy, but whether hen's egg OFC is useful in IgE-dependent egg allergy patients to avoid complete elimination remains unknown.
Methods: We identified articles in which OFCs were performed in Japanese patients diagnosed with or suspected of having IgE-mediated egg allergy. We evaluated whether the OFCs were useful to avoid the complete elimination of eggs by assessing the following: (1) the number of patients who could avoid complete elimination; (2) the number of patients who experienced serious adverse events (SAEs); or (3) adverse events (AEs); (4) improvement in quality of life (QOL); and (5) immunological changes.
Results: Fifty-nine articles were selected in the study; all the references were case series or case studies in which OFC was compared to pre-challenge conditions. The overall negative ratio against egg OFC was 62.7%, but an additional 71.9% of OFC-positive patients could take eggs when expanded to partial elimination. Of the 4182 cases, 1146 showed AEs in the OFC, and two cases reached an SAE. Two reports showed an improvement in QOL and immunological changes, although the evidence was weak.
Conclusions: OFCs against eggs may be useful to avoid complete elimination, but medical professionals should proceed with the test safely and carefully
Malignant Mesothelioma in the Thoracic Cavity of a Crj:CD(SD) Rat Characterized by Round Hyalinous Stroma
Spontaneous malignant mesothelioma was found in a 104-week-old male Crj:CD(SD)
rat. The tumor was scattered on the surface of the lung, heart, mediastinal
pleura and thoracic wall and metastasized to the alveolar septa.
Histopathologically, small flattened or cuboidal tumor cells proliferated with
stroma, formed almost normal papillary structures and reacted positively to
colloidal iron stain and immunohistochemical staining for mesothelin. Round
hyalinous stromata were pronounced, which is a characteristic feature, and the
possible reason for this is as follows; at first, a small amount of collagen
fibers was formed in the center of the clusters of several tumor cells, and then
the cell clusters expanded like balloons with an increase in the collagen
fibers
ECCD Experiment Using an Upgraded ECH System on LHD
Electron cyclotron current drive (ECCD) is an attractive tool for controlling plasmas. In the large helical device (LHD), ECCD experiments have been performed by using an EC-wave power source, gyrotron, with a frequency of 84 GHz. The maximum driven current was ?9 kA with 100 kW injection power to plasma and 8 s duration of EC-wave pulse. These years, high-power and long-pulse 77 GHz gyrotrons were newly installed. An ECCD experiment with 775 kW injection power was performed. The 77 GHz waves of 8 s pulse duration sustained the plasmas. The EC-wave beam direction was scanned toroidally, keeping the beam direction aiming at the magnetic axis in X-mode polarization. In spite of the change in the EC-wave beam direction, plasma parameters such as the line-average electron density, the central electron temperature and the plasma stored energy were kept nearly the same values for the discharges, ?0.3 × 1019 m?3, ?3 keV and ?30 kJ, except for the plasma current. The plasma current showed a systematic change with the change in the beam direction for ECCD, and at an optimum direction with N// ? ?0.3, the plasma current reached its maximum, ?40 kA. Also, current drive efficiency normalized with density and power was improved by 50% compared with that at the former 84 GHz ECCD experiment
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