Permian Foraminifera from Tunisia

22 p., 32 pl., 3 fig.http://paleo.ku.edu/contributions.htm

Permian fusulinids from Sicily

16 p., 20 pl., 1 fig.http://paleo.ku.edu/contributions.htm

Permian fusulinids from Pacific northwest and Alaska

114 p., 49 pl., 10 fig.http://paleo.ku.edu/contributions.htm

Bloating characteristics of east Texas clays

Bureau Publication GC6501 - to purchase a print copy please go to: https://store.beg.utexas.edu/geologic-circulars/383-gc6501.htmlIncidence of bloating among approximately 600 clay samples from East Texas, ranging in age from Gulfian (Late Cretaceous) to Recent, correlates principally with clay mineralogy-and pH--together an indication of bulk composition--and to a lesser extent with texture, loss on ignition, and content of nonclay refractory minerals. Clay-mineral and pH data permit prediction of bloating with an accuracy of about 80 percent. Montmorillonitic and illitic clays are the best bloaters; bloating occurs in more than 80 percent of clays consisting of less than 30 percent kaolinite, more than l 0 percent illite, and between 20 and 90 percent montmorillonite. Only 10 percent of the high-alumina clays (more than 50 percent kaolinite) bloat; these generally are plastic and carbonaceous. Value of pH is an index of the amount of certain flux and gas-forming materials in clays; accordingly, bloating incidence generally increases with increase in pH. Incidence of bloating also increases slightly with decrease in grain size, increase in plasticity, increase in loss on ignition, and decrease in content of nonclay refractory minerals.Bureau of Economic GeologyUT Librarie

Simulation of rectangular TE10 to circular TE11 terahertz mode converters

Two designs of fundamental mode rectangular to circular waveguide TE10 to TE11 mode converter are presented. The waveguide transitions are optimized for operation as an input coupler on a 372 GHz gyro-TWA for Dynamic Nuclear Polarization (DNP) enhancement of NMR imaging. A T-junction input coupler and a multiple hole directional coupler were optimized for operation between 360-384 GHz. The T-junction coupler and the multiple hole coupler exhibited bandwidths of 10% and 35% respectively with a high coupling factor of > -1 dB

Incorporating spatial dependence into a multicellular tumor spheroid growth model

Recent models for organism and tumor growth yield simple scaling laws based on conservation of energy. Here, we extend such a model to include spatial dependence to model necrotic core formation. We adopt the allometric equation for tumor volume with a reaction-diffusion equation for nutrient concentration. In addition, we assume that the total metabolic energy and average cellular metabolic rate depend on nutrient concentration in a Michaelis-Menten-like manner. From experimental results, we relate the necrotic volume to nutrient consumption and estimate both the time and nutrient concentration at necrotic core formation. Based on experimental results, we demand that the necrotic core radius varies linearly with tumor radius after core formation and extend the equations for tumor volume and nutrient concentration to the postnecrotic core regime. In particular, we obtain excellent agreement with experimental data and the final steady-state viable rim thickness.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87333/2/124701_1.pd

Measurement of a W-band gyro-TWA experiment based on a helically corrugated interaction region

Measurements of an upgraded W-band gyro-TWA with a helically corrugated waveguide and a cusp electron gun are presented. With upgraded input coupler and output systems a gain of ~37 dB was measured from the experiment with a maximum output power of over 2 kW. The amplification from the gyro-TWA was measured in the frequency range of 90 GHz to 96 GHz

Developments of a W-band gyro-TWA for high PRF operation

Latest developments of a gyrotron travelling wave amplifier (gyro-TWA) with a helically corrugated waveguide and a cusp electron gun for operation over a bandwidth of 90-100 GHz at a high pulse repetition rate (5 kHz) are presented. Performance upgrades of the input coupler, pulsed power system and beam collector with water-cooling capability were realized for the high power wide band gyro-TWA