The results are reported for a series of measurements of the propagation rate coefficient (k p) of butyl acrylate obtained from pulsed-laser polymerization (PLP). Previous attempts reported in the literature to use PLP for this monomer have failed because the data did not satisfy the internal consistency tests afforded by PLP. The problem was obviated by carrying out measurements at very low temperatures and with very short times between laser pulses. Data for k p were obtained over the range −65 to −7 °C which satisfy PLP consistency tests (invariance of the apparent k p value to laser pulse frequency, etc.). The results fit k p (dm3 mol-1 s-1) = 107.2 exp(−17.3 kJ mol-1)/RT); the confidence ellipse for these parameters is provided. These data extrapolate to a value of k p = 2.7 × 104 dm3 mol-1 s-1 at 50 °C. The higher value of the frequency factor of butyl acrylate compared to that of butyl methacrylate can be rationalized in terms of hindered rotations in the transition states.

A methodology developed to obtain rate coefficients for entry and exit (desorption) in emulsion polymerizations was applied to systems stabilized electrosterically by a copolymer of acrylic acid and styrene embedded in a styrene seed particle. This was grown as a second-stage procedure, by adding styrene and acrylic acid to a styrene seed and then polymerizing. Rate coefficients for entry (ρ) and exit (k) for subsequent homopolymerization of the resulting latices with styrene were obtained from the time dependence of the approach to steady state using both chemical and γ-radiolytic initiation; the latter was used in relaxation mode, which measures k directly. Compared to the same latices with an electrostatic stabilizer, at pH 7 the electrosteric stabilizer greatly reduced both ρ and k. When ionic strength was increased, ρ increased relative to that found for electrosterically stabilized latex in the absence of added electrolyte. For electrostatically-stabilized latices, entry is supposed to occur by aqueous-phase propagation to a critical degree of polymerization z which then undergoes irreversible entry; the present data for electrostatically-stabilized latices support this model, including its prediction that ρ be independent of particle size, all other things being equal. The decrease in ρ in the electrosterically-stabilized latices is ascribed to a “hairy” layer through which diffusion of a z-mer is slow, so that it may be terminated prior to actual entry. For electrostatically-stabilized latices, exit is supposed to occur by transfer, resulting in a monomeric radical which exits by diffusing through the aqueous phase, this event competing with intraparticle propagation; the decrease in k in the electrosterically-stabilized latices (also seen in other polymerically-stabilized systems) can be interpreted by assuming that aqueous-phase diffusion is slower in the hairy layer.

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The number of long, extended-reach wells being drilled in the oil and gas industry continues to increase. These wells present complex challenges in completion and intervention procedures because operators demand the same level of performance achieved on shallower wells while providing a cost-effective and safe solution.To reach deep target depths with coiled tubing (CT), smaller coil must be used because of reel capacity, which limits pumping rates because of pressure and velocity limitations. Many areas have road weight restrictions that will also dictate the size and length of CT that can be used. As an alternative, jointed pipe can be used; however, using jointed pipe reduces the overall efficiency of the process, as continuous pumping cannot be achieved.The new hybrid system uses both CT and jointed pipe in a single workstring. The system incorporates a unique flapper safety valve that enables seamless functioning of the string in a live well. The hybrid system enables larger CT and jointed pipe to be deployed, which results in higher pumping rates and depths. This reduces the overall job time, while improving safety and efficiency for deeper well applications, including multizone stimulation, cleanouts, drilling, and mill-outs. This paper presents the hybrid system design and benefits in multizone stimulation, drillouts, cleanouts, and other wellintervention applications. Also included is a case history to demonstrate the success of the system when applied in a multizone fracture-stimulation treatment. IntroductionCT is a vital tool for oil and gas operators to achieve safe, efficient, and effective well-intervention operations. Typically ranging beyond 25,000 ft in length and from 1 to 2.875 in. in outside diameter (OD), these continuous strings of pipe are uncoiled into live wells to perform milling, drilling, cementing, logging, perforating, fracturing, completion, or maintenance operations. Deeper well completions with extended-reach horizontal laterals have presented some unique problems to those seeking to perform well-intervention operations.

The High Definition Systems Usability Test Tool (HUTT) was developed to demonstrate and assess different human-computer interface (HCI) concepts for generic operator console positions within an advanced naval tactical display environment. To facilitate a “rapid prototyping” approach to interface development, HUTT was developed as a general purpose tool. The HUTT can be used by the human factors engineer as a rapid prototyping tool enabling quick construction and evaluation of alternative interface concepts. Changes to the organization and operation of a prototype can be made quickly, ensuring that more time can be spent on evaluation as compared to development. The demonstration will focus on the uses and operation of the HUTT. Demonstration participants will be shown how to develop, install and modify the OSF/Motif compliant graphics (pull-down menu structure and window contents) and the functionality of the HUTT to reflect changes in interface concepts.