The mechanism of self-assembly induced by H2O molecules is studied for layered saponite nanoparticles and zeolite with the cage structure by means of positronium (Ps) annihilation spectroscopy together with thermogravimetry and differential thermal analysis (TG-DTA). Prior to hydration the saponite exhibits two kinds of open spaces with their sizes of ∼3 Å and ∼9 Å, whereas open spaces with the...

A vibration-rotation-tunneling (VRT) spectrum of (H2O)4 has been recorded near 2.04 THz (67.9 cm-1). The band origin of this ∆K ) 0 symmetric rotor spectrum is shifted by 0.1 cm-1 to the blue of that of a (D2O)4 band reported previously [Science, 1996, 271, 59]. Similar to that spectrum, each transition in the (H2O)4 spectrum exhibits a regular doublet splitting. The (D2O)4 and (H2O)4 doublet s...

Rotation-tunneling a-type spectra of CH3OH•••H2O and CH3OD•••D2O were recorded between 18 and 60 GHz using direct absorption microwave spectroscopy, and for CH3OH•••H2O, CH3OH•••H2O, CH3OH•••DOH, CD3OH•••H2O, and CH3OD•••D2O between 7 and 24 GHz using a Fourier-transform microwave spectrometer. Because CH3OH and H2O are capable of both accepting and donating hydrogen bonds, there exists some qu...

In response to osmotic perturbation, the Amphiuma red blood cell regulates volume back to "normal" levels. After osmotic swelling, the cells lose K, Cl, and osmotically obliged H2O (regulatory volume decrease [RVD] ). After osmotic shrinkage, cell volume is regulated as a result of Na, Cl, and H2O uptake (regulatory volume increase [RVI] ). As previously shown (Cala, 1980 alpha), ion fluxes res...

Kinetic and isotopic tracer methods led to a simple and unifying mechanistic proposal for reactions of CH4 with CO2 and H2O, for its decomposition on Rh clusters, and for water–gas shift reactions. Kinetic rates for forward reactions were measured by correcting net rates for approach to equilibrium and by eliminating transport artifacts. These rates were proportional to CH4 pressure (5–450 kPa)...

We report the measurement of far-infrared vibration-rotation tunnelling parallel bands of two partially deuterated water trimer isotopomers: (D2O)2DOH and (H2O)2DOH at 97.2607 cm-1 and approximately 86 cm-1, respectively. The hydrogen bond rearrangement dynamics of the two mixed trimers can be described by the simplified molecular symmetry G8, which accounts for both the flipping and bifurcati...

We report the spectrum of Orion-BN/KL between 5.3 and 7.2 mm observed with the Short Wavelength Spectrometer (SWS) on board the Infrared Space Observatory. H2O lines of the –0 bending mode with l ! n 5 1 2 6.3 mm (the R-branch) are observed in absorption, while lines with l 1 6.3 mm (the P-branch) are observed in emission. Radiative transfer models including the (0, 0, 0), (0, 1, 0), and (0, 0,...

In this study we developed LaNixAl1-xO3 perovskite systems using a sol-gelmethod (with propionic acid as solvent) to use in methane-reforming reactions for producing synthesis gas. To understand the roles of the nature of the precursor and calcination conditions on the formation of LaNixAl1-xO3, we carried out identifications using NMR, FT-IR, XRD, SEM, and TEM. The precursor struc...

The title compound, C14H13N3O3·H2O, adopts an E conformation with respect to the azomethine bond and crystallizes in the amide form. An intra-molecular O-H⋯N hydrogen bond occurs. In the crystal, the lattice water molecule plays a major role in the supramolecular architecture by interconnecting adjacent molecules into a three-dimensional netwrok by means of O-H⋯O, O-H⋯N and N-H⋯O hydrogen-bondi...

OBJECTIVE To evaluate the effects of various levels of pressure support (PS) during noninvasive ventilation delivered through a helmet on breathing pattern, inspiratory effort, CO2 rebreathing, and comfort. DESIGN Physiologic study. SETTING University-affiliated hospital. PATIENTS AND PARTICIPANTS Eight healthy volunteers. INTERVENTIONS Volunteers received ventilation through a helmet w...