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The phase diagram of sodium chloride (NaCl) under laser shock compression has been studied at Linac Coherent Light Source (LCLS) at the x-ray free-electron laser facility. Both solid–solid (B1 → B2) and solid–liquid (B2 → liquid) transitions have been observed along the Hugoniot over nanosecond time scales. By combining structural measurements through in situ x-ray diffraction, pressure determination through velocimetry, and a thermal equation-of-state, the shock-compressed data are used to constrain the phase diagram of NaCl. Transformation into the B2 phase is found to occur at 28(2) GPa, and B2–liquid coexistence is observed between 54(4) and 66(6) GPa, with near full melt at 66(6) GPa. Late-time pressure release from an initial shocked B2-state results in a B2 → B1 back transformation. Our results show agreement with previous static compression data, suggesting that the time scale for melting is very rapid and that equilibrium states in NaCl are being accessed over nanosecond time scales. A multiphase equation-of-state description of NaCl incorporated into a one-dimensional hydrocode is used to interpret pressure and temperature evolution over these rapid time scales.

Recent studies show a face-centered cubic (fcc) to body-centered cubic (bcc) transformation along the shock Hugoniot for several metals (i.e., Cu, Au, and Ag). Here, we combine laser-shock compression of Cu foils on nanosecond timescales with in situ x-ray diffraction (XRD) to examine the microstructural changes with stress. We study the fcc phase and the phase transition from fcc to bcc (pressures greater than 180 GPa). Textural analysis of the azimuthal intensities from the XRD images is consistent with transformation into the bcc phase through the Pitsch-distortion mechanism. We use embedded atom model molecular dynamics simulations to determine the stability of the bcc phase in pressure–temperature space. Our results indicate that the bcc phase is stabilized only at high temperatures and remains stable at pressures greater than 500 GPa.

Combining an x-ray free electron laser with a high-power laser driver enables the study of equations-of-state, high strain-rate deformation processes, structural phase transitions, and transformation pathways as a function of pressure to hundreds of GPa along different thermodynamic compression paths. Future high repetition-rate laser operation will enable data to be accumulated at >1 Hz, which poses a number of experimental challenges, including the need to rapidly replenish the target. Here, we present a combined shock compression and an x-ray diffraction study on epoxy (50% vol.)-crystalline grains (50% vol.) slurry targets, which can be fashioned into extruded ribbons for high repetition-rate operation. For shock-loaded NaCl-slurry samples, we observe pressure, density, and temperature states within the embedded NaCl grains consistent with observations from shock-compressed single-crystal NaCl.

The infusion of 10% solutions of glucose, galactose and fructose into normal subjects caused significant increases in the excretion ratios of phosphate and alpha-amino nitrogen. The infusions of 10% xylose solutions at the same rate caused similar hemodynamic and osmotic alterations, but no changes in the excretion of these substances. Column chromatographic analysis revealed that glucose infusion impaired the reabsorption of numerous amino acids. The excretion ratios of phosphate and alpha-amino nitrogen could not be correlated with the plasma hexose concentrations or rate of hexose excretion, but other data are cited to support the thesis that the observed inhibition of phosphate and amino acid reabsorption is due to a toxic effect of the hexoses or their metabolites on the renal tubular transport system.

1. 1. Decreasing the incubation medium Na+ concentration below physiologic levels resulted in decreased transport of Na+ and water in the isolated rabbit jejunum as well as diminution of amino acid transport. 2. 2. Ouabain inhibited the transport of Na+ and amino acids in everted jejunal sacs. 3. 3. Reduction of medium Na+ was associated with decreased tissue Na+ and K+ content while ouabain produced elevated tissue Na+ and reduced tissue K+ concentrations. 4. 4. Kinetic analysis of amino acid-uptake data showed that ouabain and reduction of medium Na+ caused a slowing of both influx and, to a lesser degree, efflux coefficients. 5. 5. The Na+ ion was shown to affect energy-independent (diffusion) as well as energy-dependent (active) transport of amino acids.