Molecular dynamics simulations have been carried out for liquid–vapor interface of water and also Lennard-Jones system. Surface tension surface excess energy are calculated, from which entropy is evaluated. These thermodynamic quantities suggest the existence some liquid-structural change near water, not seen in For orientational structuring studied two types orientation found. In vapor side, a molecule has tendency projecting one hydrogen atom toward vapor, liquid prefers to lie down on...

Molecular dynamics computer simulation was carried out to investigate the of vapor phase homogeneous nucleation at triple point temperature under supersaturation ratio 6.8 for a Lennard-Jones fluid. To control system temperature, 5000 target particles were mixed with soft-core carrier gas particles. The observed rate is seven orders magnitude larger than prediction classical theory. kinetically defined critical nucleus size, which growth and decay rates are balanced, 30–40, as large...

Molecular-dynamics simulations of liquid methanol have been carried out at two temperatures (T=300 and 200 K) to investigate the dynamics hydrogen bonding. The mean lifetime bonds (defined in terms a time-averaged pair energy) is calculated found be 5–7 ps 300 K, through results depend on averaging time used bond definition. At K becomes much longer, by one order magnitude or more. A bonding state defined for each molecule according number bonds, states rate constants transition between are...

Hydrogenated amorphous silicon (a-Si:H) films, used for light absorbers of p-i-n solar cells, were deposited at various deposition rates (Rd) ranging over two orders magnitude (Rd ∼ 2 × 10−3–3 10−1 nm/s) by using diode and triode plasma-enhanced chemical vapor (PECVD). The impact varying Rd on the light-soaking stability cells has been investigated. Although a reduction mitigates light-induced degradation in typical range (>10−1 nm/s), it remains present even very low (<10−2...

Homogeneous nucleation process in the vapor phase of water is investigated with a molecular dynamics computer simulation at 350 K under supersaturation ratio 7.3. Using method similar to Lennard-Jones fluid (Part I), rate three orders magnitude smaller than prediction classical theory. The kinetically defined critical nucleus size 30–45, much larger thermodynamically value 1.0 estimated Free energy cluster formation from distribution steady state time region. predicted this free agrees...

Results of molecular dynamics computer simulation are presented for liquid–vapor interface water–methanol mixture various compositions at room temperature. The composition dependence calculated surface tension is typical aqueous solutions organic compounds. outermost layer saturated with methanol even low bulk concentrations methanol. density profile each component seems oscillatory some compositions.

Computer simulations with molecular dynamics technique were carried out to investigate properties of liquid–vapor interface methanol for a wide temperature range 160–350 K. The estimated surface excess thermodynamic quantities, especially entropy, are characteristic strongly hydrogen-bonding liquids, but the density profile resembles that simple fluids. Orientational structuring near was also studied, and one apparent tendency, much stronger than water, observed; molecule projects its methyl...

The Young–Laplace (Y–L) equation describes the difference between inside pressure and outside of a spherical bubble due to surface tension. Y–L is simply deduced from mechanical stability bubble, but it still controversial whether can be used for tiny bubbles, such as "nano bubble", because divergently increases radius R decreases. We investigated vapor in Lennard-Jones liquid with molecular dynamics simulation, mainly looking into its stabilities. generated various sizes (R≃1.7–5 nm argon...

We investigated the initial stage of nucleate boiling on ideally smooth surface with a molecular dynamics simulation technique. Lennard-Jones (LJ) model liquid was confined in rectangular cell, contacting flat solid wall. The wall consists fcc crystal LJ-like particles. After system thermally equilibrated, temperature particles raised to transfer thermal energy liquid. examined two cases, overall heating where is kept constant all over area, and partial (spot) regions cooling are placed. In...

We report that thin-film silicon solar cells exhibiting high stabilized efficiencies can be obtained by depositing hydrogenated amorphous (a-Si:H) absorbers using triode-type plasma-enhanced chemical vapor deposition. The improved light-soaking stability and performance of are also realized optimizing the device design, such as p p–i buffer layers. As a result, we attain independently confirmed 10.1–10.2% for a-Si:H single-junction (absorber thickness: ti = 220–310 nm) 12.69% an (ti 350...

A magnetoplumbite type of hexagonal Ba-ferrite films, whose c-axis crystallites is well oriented perpendicularly to the film plane, have been prepared by means a conventional rf diode sputtering system. Morphological and crystallographic characteristics sputtered films depend strongly on preparation conditions such as distance between target substrate d <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T-S</inf> partial pressure oxygen gas P...

Microstructural changes of single-crystal 4H silicon carbide (SiC) induced by nanoindentation under various conditions were investigated. It was found that at different crystal orientations Raman spectroscopic characteristics. Cross-sectional observation transmission electron microscopy indicated a very deep subsurface damage region formed where dislocations occurring along the basal planes, grains rotation and micro-cracks observed. The microstructures regions strongly affected conditions....

Molecular dynamics computer simulations were carried out to investigate the of evaporation and condensation for argon at temperature 80 100 K. From decrease survival probability vapor molecules, ratio self reflection collision is estimated be 12%–15%, only weakly dependent on temperature. This suggests that molecules are in condition almost complete capture, considered a barrierless process. The total which evaluated with flux correlation 20% both difference between these two ratios ascribed...

The absorption spectra, ethidium bromide fluorescent spectra and circular dichroism (CD) indicate that six β-carboline derivatives, norharman, harman, harmol, harmine, harmalol harmaline intercalate into DNA. This result is supported by unwinding experiments using the superhelical plasmid pBR322 DNA, magnitude of intercalation except for decreased in order harmol>harmine>harmaline>harman>norharman. potency interactions was further determined spectrophotometric titration. Scatchard plots were...

The rates of evaporation and condensation methanol under the vapor–liquid equilibrium condition at temperature 300 350 K are investigated with a molecular dynamics computer simulation. Compared argon system (reported in part I), ratio self-reflection is similar (∼10%), but molecule exchange several times larger than argon, which suggests that conventional assumption as unimolecular process completely fails for associating fluids. resulting total coefficient 20%–25%, has quantitative...

Ba 0.5 Sr Co x Fe 1-x O 3-δ (BSCF) has garnered considerable attention as a promising catalyst for the alkaline oxygen evolution reaction (OER). However, intrinsic roles of and at active sites during...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPeriodic Motion of Large DNA Molecules during Steady Field Gel ElectrophoresisHidehiro Oana, Yuichi Masubuchi, Mitsuhiro Matsumoto, Masao Doi, Yukiko Matsuzawa, and Kenichi YoshikawaCite this: Macromolecules 1994, 27, 21, 6061–6067Publication Date (Print):October 1, 1994Publication History Published online1 May 2002Published inissue 1 October 1994https://doi.org/10.1021/ma00099a019RIGHTS & PERMISSIONSArticle Views137Altmetric-Citations51LEARN ABOUT...

Direct numerical simulation is employed to study the behaviors of droplets impinging a surface with wettability difference. Unlike four stages droplet passing through on homogeneous surfaces, results illustrate that undergoes asymmetric spreading, retracting, detaching, and self-migrating phases when it impacts nonuniform decorations. This happens because unbalanced Young's force acting three-phase contact line around drop periphery, which points toward direction increasing wettability, or...