Neutral-atom recombination lasers in CO2laser-vaporized target material

Neutral-atom recombination lasers in the vaporized plasmas of 28 different elements are reported. The results, which are consistent with the predictions of a simple model of a plasma-recombination laser, demonstrate the wide applicability of CO2laser-produced plasmas as sources for laser excitation.     

An integrated,intelligent design environment

An integrated, intelligent design environment was designed and implemented. The heart of the environment is a userfriendly, menu-driven CAD system integrated with an information controller. The system allows the engineer to design in a feature-based, object-oriented manner. Designs are stored in a data base and checked for manufacturability and assembly by an expert system. This paper describes the design of the information integration controller and the man-machine interfaces of the intelligent design system.     

In Situ Measurement of Nonlinear Shear Modulus of Silty Soil

A new field test method to evaluate in situ nonlinear shear modulus of soils was developed. The method utilizes a drilled shaft as a cylindrical, axisymmetric source for shear loading of soil at depth. The applicability of the test method was studied by conducting small-scale, prototype experiments at a “calibration” field site in Austin, Texas. Numerous conventional in situ and laboratory measurements were performed to characterize the soil at the field site. The “small-scale” nature of the tests involved using a 381?mm (15?in.) diameter, 3.7?m (12?ft) long drilled shaft. Experimental results from this field study provided an opportunity to compare laboratory and field measurements of the G?log?γ and G/Gmax?log?γ curves. This comparison was used to investigate the accuracy of common procedures relating field and laboratory modulus reduction curves. Nonlinear modulus measurements were performed at depths of 1.8?to?2.1?m (6?to?7?ft) in a silt (ML). The field G/Gmax?log?γ curve for this soil at low confining pressures are in general agreement with the laboratory curve from an intact specimen as well as empirical curves.     

Evaluation of Sonochemical Destruction of PCE in In Situ Flushing Waste Fluids

Remediation of source zones at sites contaminated with dense non-aqueous-phase liquids using aggressive in situ flushing technologies, such as the addition of chemical additives known as cosolvents, have been implemented and successfully demonstrated in recent field tests. However, treatment of the waste fluids generated from such cleanup technologies has not received much attention. The purpose of this laboratory research was to evaluate the feasibility of using sonication as a method for treating waste fluids produced during in situ alcohol flushing at a site contaminated with a dense non-aqueous-phase liquid. Experimental results showed that sonochemical destruction of perchloroethylene (PCE) followed pseudo first-order kinetics and that increasing ethanol cosolvent percentages in the aqueous effluent resulted in decreasing degradation rates of PCE in solution. The energy efficiency (G = degradation∕energy input) of the sonication treatment also decreased as the ethanol volume fraction increased. Overall, sonication was seen to degrade PCE in aqueous solutions, becoming less effective as the cosolvent fraction increased.     

Developing a Simple NMR Interface: WWNMR

We have designed and implemented an automated walkup NMR computer application for use by synthetic chemists. The Wyeth Walkup NMR (WWNMR) application is a TCL/TK graphical user interface front-end to Varian's NMR automation routines. The key feature of WWNMR is that the chemists are isolated from the spectrometer's control program (VNMR) and only enter information to WWNMR windows for a sample to be run. The resulting data can be printed out on paper, or stored on disk for easy access by all users at their desktops. Proton and carbon NMR experiments are available. An overview of the WWNMR application will be presented.     

Fatigue processes in metals—role of aqueous environments

The response of a wide range of metals under the action of an applied stress and in environments spanning an entire range of aggressiveness, from the very inert to aggressive has been the subject of several investigations. Most of these studies have focused on mechanisms governing fatigue crack propagation and little attention has been paid to the effect of environment on fatigue crack initiation. A comprehensive understanding of the influence of aqueous environments has been hampered by the complexity of the problem, the difficulties in understanding the various micromechanisms governing crack initiation and crack propagation and by an absence of a truly interdisciplinary attack of the problem. In this paper, several of the fatigue crack initiation models are presented and the micromechanisms governing fatigue crack initiation are examined. The various processes that control the phenomenon of cracking including aqueous environment enhanced fatigue crack growth are also highlighted in this review.     

Determination of the Impact of Glycolate on Cs,Sr, and Actinide Separations in High-Level Waste

The Defense Waste Processing Facility (DWPF), responsible for vitrifying high-level waste (HLW) at the Savannah River Site (SRS), is planning to introduce glycolic acid as a reductant during chemical conditioning of the waste prior to vitrification. A portion of this glycolic acid may be recycled back to the tank farm as sodium glycolate. Since glycolate can serve as a complexing agent for a variety of metallic ions, recent studies were performed to examine the effect of glycolate on the removal of Sr and actinides by monosodium titanate (MST) and modified MST (mMST) and the separation of Cs by the caustic-side solvent extraction (CSSX) process.     

Analysis‐preserving video microscopy compression via correlation and mathematical morphology

The large amount video data produced by multi‐channel, high‐resolution microscopy system drives the need for a new high‐performance domain‐specific video compression technique. We describe a novel compression method for video microscopy data. The method is based on Pearson's correlation and mathematical morphology. The method makes use of the point‐spread function (PSF) in the microscopy video acquisition phase. We compare our method to other lossless compression methods and to lossy JPEG, JPEG2000, and H.264 compression for various kinds of video microscopy data including fluorescence video and brightfield video. We find that for certain data sets, the new method compresses much better than lossless compression with no impact on analysis results. It achieved a best compressed size of 0.77% of the original size, 25× smaller than the best lossless technique (which yields 20% for the same video). The compressed size scales with the video's scientific data content. Further testing showed that existing lossy algorithms greatly impacted data analysis at similar compression sizes. Microsc. Res. Tech. 78:1055–1061, 2015. © 2015 Wiley Periodicals, Inc.     

Bilateral Laplace Transforms on Time Scales: Convergence, Convolution, and the Characterization of Stationary Stochastic Time Series

The convergence of Laplace transforms on time scales is generalized to the bilateral case. The bilateral Laplace transform of a signal on a time scale subsumes the continuous time bilateral Laplace transform, and the discrete time bilateral z-transform as special cases. As in the unilateral case, the regions of convergence (ROCs) time scale Laplace transforms are determined by the time scale’s graininess. ROCs for the bilateral Laplace transforms of double sided time scale exponentials are determined by two modified Hilger circles. The ROC is the intersection of points external to modified Hilger circle determined by behavior for positive time and the points internal to the second modified Hilger circle determined by negative time. Since graininess lies between zero and infinity, there can exist conservative ROCs applicable for all time scales. For continuous time (ℝ) bilateral transforms, the circle radii become infinite and results in the familiar ROC between two lines parallel to the imaginary z axis. Likewise, on ℤ, the ROC is an annulus. For signals on time scales bounded by double sided exponentials, the ROCs are at least that of the double sided exponential. The Laplace transform is used to define the box minus shift through which time scale convolution can be defined. Generalizations of familiar properties of signals on ℝ and ℤ include identification of the identity convolution operator, the derivative theorem, and characterizations of wide sense stationary stochastic processes for an arbitrary time scales including autocorrelation and power spectral density expressions.