Abstract: Described are very high molecular weight (e.g., over 2 million, such as 3-20 million g/mol) starch-based materials, and formulations including such, which can be spun in spunbond, melt blown, yarn, or similar processes. Even with such very high molecular weights, the formulations can be processed at commercial line speeds, with spinneret shear viscosities of 1000 sec?1, without onset of melt flow instability. The starch-based material can be blended with one or more thermoplastic materials having higher melt flow index value(s), which serve as a diluent and plasticizer, allowing the very viscous starch-based component to be spun under such conditions. The particular melt flow index characteristics of the thermoplastic diluent material can be selected based on what type of process is being used (e.g., spunbond, melt blown, yarn, etc.). The starch-based material may exhibit high shear sensitivity, strain hardening behavior, and/or very high critical shear stress (e.g., at least 125 kPa).

Abstract: Described are very high molecular weight (e.g., over 2 million, such as 3-20 million g/mol) starch-based materials, and formulations including such, which can be spun in spunbond, melt blown, yarn, or similar processes. Even with such very high molecular weights, the formulations can be processed at commercial line speeds, with spinneret shear viscosities of 1000 sec?1, without onset of melt flow instability. The starch-based material can be blended with one or more thermoplastic materials having higher melt flow index value(s), which serve as a diluent and plasticizer, allowing the very viscous starch-based component to be spun under such conditions. The particular melt flow index characteristics of the thermoplastic diluent material can be selected based on what type of process is being used (e.g., spunbond, melt blown, yarn, etc.). The starch-based material may exhibit high shear sensitivity, strain hardening behavior, and/or very high critical shear stress (e.g., at least 125 kPa).

Abstract: A method for recording and pre-processing high fidelity vibratory seismic data includes measuring the motion of the vibrator which is related to the vibrator applied force times a transfer function of minimum phase, causal, linear system relating the actual vibrator output with the measured vibrator motion, determining a ratio by dividing the vibratory seismic data by the measured motion of the vibrator to remove the unknown applied force leaving the earth reflectivity times a time derivative divided by a minimum phase function, minimum phase band pass filtering the resulting ratio and performing minimum phase deconvolution to remove the time derivative divided by the transfer function of minimum phase. The method may also include the steps of receiver ensemble deconvolution, statics correction, F-K filtering for noise, zero phase spiking deconvolution and model dephasing. The actual signal that the vibrator is sending into the ground is used in pre-processing.

Abstract: In marine seismic exploration, measurements of reflectivity and water depth are made from seismograms produced by the firing of a seismic energy source towed by a marine vessel. The measurements are made by generating the auto-correlation coefficients of a window of the seismogram and combining these coefficients for different time lags. The time lag producing the minimum energy in the combined autocorrelation coefficients represents water depth. The reflectivity of the water bottom is obtained by generating an estimate of the reflectivity from the values of the auto-correlation function of the window, and modifying this estimate by a factor which converts the estimate to the reflectivity. The measured water depth and reflectivity are converted into an inverse operator. A linear array of sources is then fired in a sequence such that the acoustic pulses combine to produce a resultant acoustic pressure wave having the inverse time domain operator characteristics.