Techniques for the production of short wavelengths in the extreme ultraviolet wavelength range aredescribed, spanning low-order harmonic generation in the perturbative regime for narrow bandwidth XUV productionto the plateau-regime with the three-step collisional model for the generation of high harmonics with broadband ultrafastpulses. In addition, the intermediate regime is discus...

We combine different wavelengths from an intense high-order harmonics source with variable delay at the focus of a split-mirror interferometer to conduct pump-probe experiments on gas-phase molecules. We report measurements of the time resolution (<44 fs) and spatial profiles (4 μm × 12 μm) at the focus of the apparatus. We demonstrate the utility of this two-color, high-order-harmonic techniqu...

cupric oxide nanostructures were synthesized via a simple reaction between copper nitrate and sodium hydroxide using a sonochemical-assisted method. the synthesized cuo was then characterized using x-ray diffraction, scanning electron microscopy, transmission electron microscopy, fourier transform infrared, ultraviolet-visible and photoluminescence spectroscopy. our studies show that the cuo na...

The recent spectroscopy of water vapour in the ground electronic state is reviewed. Experimental advances from the microwave to the near ultraviolet spectral regions are surveyed. On the theoretical front, new approaches to the calculation of vibration–rotation energy levels are covered. Water spectroscopy finds extensive application in astronomy, atmospheric science and combustion research. An...

The photodynamics in symmetric and unsymmetric β-diketones are studied with transient absorption in the deep-UV. Excitation leads to ultrafast ESIPT while further relaxation and isomerization processes depend on the molecular symmetry and solvent environment. OCIS codes: (320.7150) Ultrafast spectroscopy; (300.6540) Spectroscopy, ultraviolet; (190.7110) Ultrafast nonlinear optics

We have obtained HST/STIS data for a total of eleven polars as part of a program aimed to compile a homogeneous database of high-quality far-ultraviolet (FUV) spectra for a large number of cataclysmic variables (CVs). Of the eleven polars, eight were found in a state of low accretion activity (V347Pav, VVPup, V834Cen, BLHyi, MRSer, STLMi, RXJ1554.2+2721 and V895Cen) and three in a state of high...

altitude distributions of CS2 , H2S, and NH3 suggest that CS2 was created by chemistry in the plume but that H2S and NH3 We present a comprehensive analysis of spectra in the 175– were injected into the stratosphere from below by upwelling 230 nm wavelength region obtained by the Faint Object Spectroover spatial scales of thousands of kilometers associated with graph of the Hubble Space Telesco...

introduction the concentration of substances, including urea, creatinine, and uric acid, can be used as an index to measure toxic uremic solutes in the blood during dialysis and interdialytic intervals. the on-line monitoring of toxin concentration allows for the clearance measurement of some low-molecular-weight solutes at any time during hemodialysis.the aim of this study was to determine the...

We present and discuss near-ultraviolet and optical ground-based spectra of the 20 brightest Seyfert 2 nuclei, and HST ultraviolet images and ultraviolet spectroscopy for a few of them. The goal is to study the starburst-AGN connection and the origin of the featureless continuum. The results indicate that half of the nuclei in the sample harbor a young and/or intermediate age population. These ...

We study the relaxation dynamics of pyrrole after excitation with an 8 eV pump pulse to a state just 0.2 eV below the ionization potential using vacuum ultraviolet/ultraviolet pump probe spectroscopy. Our measurements in conjunction with electronic structure calculations indicate that pyrrole undergoes rapid internal conversion to the ground state in less than 300 fs. We find that internal conv...