3,742 research outputs found
Balanced-bellows spirometer
Compact balanced-bellows dry type spirometer was designed to be insensitive to acceleration fields along any or all coordinate axes. It provides true indication of respiratory action of test subject without need for calibration in acceleration fields
Impact of Mesh Tracks and Low-Ground-Pressure Vehicle Use on Blanket Peat Hydrology
No abstract available
History of the School of Communication: A Perspective on Communication, Change, and Community, 1985-2008
This departmental history was written on the occasion of the UND Quasquicentennial in 2008.https://commons.und.edu/departmental-histories/1077/thumbnail.jp
Coupled Plasmon/Molecule Dynamics Near Core-Shell Nanoparticles: Synthesis, Ultrafast Characterization, and Quantum/Classical Modeling
In this dissertation, the resonance coupling of chromaphoric dyes adsorbed on the surface of plasmonic nanoparticles (NPs) are investigated using a combined theoretical and experi- mental approach. Colloidal gold, gold-silver core-shell, silver-gold core-shell, and gold-silver- gold core-shell-shell NPs are considered. These NPs are thiolated with mercaptosuccinic acid, and malachite green dyes are adsorbed to the surface of the nanoparticle (NP) via elec- trostatic interactions. Second harmonic generation is used to determine the surface to the isotherm of the molecular dyes to the colloidal nanoparticle surface. Adsorption isotherms show that the SHG intensity increases as the concentration of dye increases, reaching a plateau signal at saturation. These adsorption isotherms are fit with a modified Langmuir equation to determine the best fit parameters corresponding to the free energy and adsorbate population at the surface. However, the molecular orientation and separation from the NP surface is unknown experimentally.
Strong coupling at the NP-molecule interface results in a new quantum state called a polariton. Difference extinction measurements reveal these polaritonic states overlapped in a Fano-like resonance profile. A hybrid quantum/classical theoretical model is presented to model the plasmon-molecule interactions of adsorbed molecules at the surface of a mer- captosuccinic acid capped gold and silver-gold core-shell NP. This model employs classical electrodynamics using a finite-difference time-domain (FDTD) approach for the NP response and a 3-level quantum treatment for the molecules. The coupling at the surface is highly dependent on the adsorbate/NP separation distance and molecule transition dipole angle. Increasing the separation distance or transition dipole angle results in a weaker coupling between the NP and molecule, decreasing the splitting energy. This allows us to predict the most likely separation distance and transition dipole angle for a given dye, capping agent and NP composition
The Changing Economic Status of Disabled Women, 1982–1991: Trends and Their Determinants
This study provides an assessment of the intertemporal economic well-being of a representative sample of women who began receiving Social Security Disability Insurance (SSDI) in 1980–81. We compare their economic circumstances over the 1982–1991 period with those of disabled men who also began receiving SSDI in those years and with those of a matched sample of nondisabled women who had sufficient work experience for benefit eligibility should they have become disabled. In 1982, the new SSDI women beneficiaries were a relatively poor segment of U.S. society: one quarter of them lived in poverty and 48 percent had incomes below 150 percent of the poverty line. As of 1991, over one-half of these disabled women lived in families with income below 150 percent of the poverty line. Social Security benefits to disabled women have played an important, and growing, role in sustaining economic status. Nevertheless, the level of well-being of these women lies substantially below that of the comparison groups. We statistically relate the poverty status of these new female recipients to sociodemographic factors that would be expected to contribute to lower levels of well-being, and we simulate the effect of Social Security benefits in reducing poverty and replacing earnings. We suggest a number of SSDI-related policy changes that could, at low cost, reduce poverty among the poorest women.
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