cssi/SciSciGPT-SciSciNet huggingface dataset:
A bimodal approximation for reacting turbulent flows. I - Description of the model.

21 Winkler, E. M., "Design and calibration of stagnation temperature probes for use at high supersonic speeds and elevated temperature," J. Appl. Phys. 25, 231-232 (February 1954). 22 Danberg, J. E., "The equilibrium temperature probe, a device for measuring temperatures in hypersonic boundary layers/' U. S. Naval Ordnance Lab., White Oak Md., NOL TR 61-2 (February 1962). 23 Hill, F. K., "Turbulent boundary layer measurements at Mach numbers from 8 to 10," Phys. Fluids 2, 668-680 (1959). 24 Bertram, M. H. and Neal, L., Jr., "Recent experiments in hypersonic turbulent boundary layers," NASA Langley Research Center, Langley Station, Va.; also presented at AGARD Specialist Meeting on "Recent Development in Boundary Layer Research," Naples, Italy (May 1965). 25 Cohen, N. B., "A method for computing turbulent heat transfer in the presence of a streamwise pressure gradient for bodies in high-speed flow," NASA Memo. 1-2-59L (March 1959). 26 Walz, A., "Compressible turbulent boundary layers," International Symposium on the "Mechanique de le Turbulence" (Centre National de la Recherche Scientifique, Paris, 1962), pp. 299-350. 27 McLafferty, G. H. and Barrer, R. E., "The effect of adverse pressure gradients on the characteristics of turbulent boundary layers in supersonic stream," J. Aerospace Sci. 29, 1-10(1962). 28 Kepler, C. E. and O'Brien, R. L., "Supersonic turbulent boundary layer growth over cooled walls in adverse pressure gradients," United Aircraft Corp., Aeronautical Systems Div. ASD-TDR-62-87 (October 1962). 29 Burke, A. F., "Turbulent boundary layers on highly cooled surfaces at high Mach numbers," Proceedings of Symposium on Aerothermoelasticity, Dayton, Ohio (1961), pp. 704-741; also U.S. Air Force, Aeronautical Systems Div., Wright-Patterson Air Force Base, Ohio, TR 6-645 (1961). 30 Morkovin, M. V., "Effects of high acceleration on a turbulent supersonic shear layer," Proceeding of the 1955 Heat Transfer and Fluid Mechanics Institute (Stanford University Press, Stanford, Calif., 1955), pp. IV, I-IV, 17. 31 Libby, P. A. and Baronti, P. O., "A transformation theory of the turbulent compressible boundary layer with pressure gradient and heat transfer," General Applied Science Labs., Inc., TR 455 (August 1964).
Oxidatively Responsive Chain Extension to Entangle Engineered Protein Hydrogels

Engineering artificial protein hydrogels for medical applications requires precise control over their mechanical properties, including stiffness, toughness, extensibility, and stability in the physiological environment. Here we demonstrate topological entanglement as an effective strategy to robustly increase the mechanical tunability of a transient hydrogel network based on coiled-coil interactions. Chain extension and entanglement are achieved by coupling the cysteine residues near the N- and C-termini, and the resulting chain distribution is found to agree with the Jacobson–Stockmayer theory. By exploiting the reversible nature of the disulfide bonds, the entanglement effect can be switched on and off by redox stimuli. With the presence of entanglements, hydrogels exhibit a 7.2-fold enhanced creep resistance and a suppressed erosion rate by a factor of 5.8, making the gels more mechanically stable in a physiologically relevant open system. While hardly affecting material stiffness (only resulting in a 1.5-fold increase in the plateau modulus), the entanglements remarkably lead to hydrogels with a toughness of 65 000 J m^(–3) and extensibility to approximately 3000% engineering strain, which enables the preparation of tough yet soft tissue simulants. This improvement in mechanical properties resembles that from double-network hydrogels but is achieved with the use of a single associating network and topological entanglement. Therefore, redox-triggered chain entanglement offers an effective approach for constructing mechanically enhanced and responsive injectable hydrogels.
Synthesis and reactions of chloroazodienes. A new and general synthesis of pyridazines

Abstract The reaction of dichlorohydrazones with Hunig's base gives 4-chloroazodienes, which were found to combine with a variety of electron rich olefins to yield chloro-substituted tetrahydropyridazines. These chloroazodiene cyclizations are best characterized as inverse electron demand, 4+2 hetero Diels-Alder reactions that maintain a high degree of regio- and stereochemical control. The chloro-substituted tetrahydropyridazines that are formed give high yields of substituted pyridazines upon treatment with base. The sequence of a chloroazodiene cyclization to a tetrahydropyridazine followed by an aromatization constitutes a new and general synthesis of substituted pyridazines.
A two-loop test of M(atrix) theory

Abstract We consider the scattering of two Dirichlet zero-branes in M(atrix) theory. Using the formulation of M(atrix) theory in terms of ten-dimensional super Yang-Mills theory dimensionally reduced to (0+1) dimensions, we obtain the effective (velocity-dependent) potential describing these particles. At one loop we obtain the well-known result for the leading order of the effective potential V eff ∼ v 4 / r 7 , where v and r are the relative velocity and distance between the two zero-branes, respectively. A calculation of the effective potential at two loops shows that no renormalizations of the v 4 term of the effective potential occur at this order.
DAMAGE DETECTION IN SMART STRUCTURES THROUGH SENSITIVITY ENHANCING FEEDBACK CONTROL

Abstract Non-destructive damage detection and isolation in structures using modal information is hindered by the sensitivity of modal frequencies to small changes in mass, stiffness, and damping parameters induced by damage. Here, a method of enhancing modal frequency sensitivity to damage using feedback control is introduced. Using state feedback, closed-loop modal frequencies are placed at locations in the complex plane that enhance sensitivity to particular types of damage. The method is intended for smart structures, which embody self-actuation and self-sensing capabilities. A simple example introduces the principle of sensitivity enhancing control for a single-degree-of-freedom structure. Then, the method is applied to finite-element models of a cantilevered beam to demonstrate the magnitude of sensitivity enhancement achievable for modest, local damage. Methods of implementing sensitivity enhancing full state or output feedback using point measurements of strain along the beam are described. Simulation results show that significant enhancement in sensitivity of modal frequencies of vibration to damage can be achieved using a single actuator and multiple strain sensors along the beam. The methodology enables a “dual use” smart structure—one that can be used for both vibration suppression and damage detection.
Progress toward the synthesis of a biomimetic membrane

Abstract Ubiquinone has antioxidant properties and is important in the conversion of products from glycolysis and the citric acid cycle to ATP. We report the synthesis of the necessary components of a biological membrane mimic that can serve as a model system for elucidating the third step in the prokaryotic biosynthesis of ubiquinone.
Auditory Perspective Taking

Effective communication with a mobile robot using speech is a difficult problem even when you can control the auditory scene. Robot self-noise or ego noise, echoes and reverberation, and human interference are all common sources of decreased intelligibility. Moreover, in real-world settings, these problems are routinely aggravated by a variety of sources of background noise. Military scenarios can be punctuated by high decibel noise from materiel and weaponry that would easily overwhelm a robot's normal speaking volume. Moreover, in nonmilitary settings, fans, computers, alarms, and transportation noise can cause enough interference to make a traditional speech interface unusable. This work presents and evaluates a prototype robotic interface that uses perspective taking to estimate the effectiveness of its own speech presentation and takes steps to improve intelligibility for human listeners.
A relational hierarchical model for decision-theoretic assistance

Building intelligent assistants has been a long-cherished goal of AI, and many were built and fine-tuned to specific application domains. In recent work, a domain-independent decision-theoretic model of assistance was proposed, where the task is to infer the user’s goal and take actions that minimize the expected cost of the user’s policy. In this paper, we extend this work to domains where the user’s policies have rich relational and hierarchical structure. Our results indicate that relational hierarchies allow succinct encoding of prior knowledge for the assistant, which in turn enables the assistant to start helping the user after a relatively small amount of experience.
Fusion Frames and the Restricted Isometry Property

We show that RIP frames, tight frames satisfying the restricted isometry property, give rise to nearly tight fusion frames, which are nearly orthogonal and, hence, are nearly equi-isoclinic. We also show how to replace parts of the RIP frame with orthonormal sets while maintaining the restricted isometry property.
Ranked Set Sampling

The most common sampling approach for collecting data from a population with the goal of making inferences about unknown features of the population is a simple random sample (SRS). There is a probabilistic guarantee that each measured observation in an SRS can be considered representative of the population. Despite this assurance, there remains a distinct possibility that a specific SRS might not provide a truly representative picture of the population. With that in mind, statisticians have developed a variety of ways to guard against obtaining such unrepresentative samples. Sampling designs such as stratified sampling, probability sampling, and cluster sampling all provide additional structure on the sampling process to improve the likelihood that the collected sample data do, indeed, provide a good representation of the population. A secondary goal in most data collection settings is to minimize the costs associated with obtaining the data. Ranked set sampling (RSS) is a relatively recent development that addresses both of these issues. It uses additional information from the population to provide more structure to the data collection process and decreases the likelihood of an unrepresentative sample. In addition, it is designed to minimize the number of measured observations required to achieve the desired precision in making inferences. In this article, we provide a general introduction to both balanced and unbalanced RSS, describing the basic approaches for collecting each type of RSS and some of the associated properties. We discuss a number of important factors that affect the performance of RSS procedures. Copyright © 2010 John Wiley & Sons, Inc. For further resources related to this article, please visit the WIREs website.
Stereocontrolled total synthesis of the penicillanate ester (2S,5R)-benzyl 3,3-dimethyl-7-oxo-4-thia-1-azabicyclo [3.2.0] heptane-2-carboxylate

Abstract (3R)-4-Acetoxy-3-trimethylsilyl-2-azetidinone, was converted into optically pure benzyl penicillanate in seven steps (22%) using (benzyloxy)nitromethane as a reagent for ring annulation.
The Limits of Equality: Insights from the Israeli Kibbutz

What limits the capacity of society to redistribute? What determines the structure of compensation in organizations striving for income equality? This paper addresses these questions by investigating the economic and sociological forces underlying the persistence of the Israeli kibbutzim, communities based on the principle of income equality. To do this, I exploit newly assembled data on kibbutzim and a financial crisis in the late 1980s that affected them differentially. The main findings are that (1) productive individuals are the most likely to exit and a kibbutz's wealth serves as a lock-in device that increases the value of staying; (2) higher wealth reduces exit and supports a high degree of income equality; and (3) ideology facilitates income equality. Using a simple model, I show that these findings are consistent with a view of the kibbutz as providing optimal insurance when members have the option of leaving. More generally, these findings contribute to an understanding of how mobility limits redistribution, and to an understanding of the determinants of the sharing rule in other types of organizations, such as professional partnerships, cooperatives, and labor-managed firms.
Ultrathin film magnetic research at the Naval Research Laboratory

Scientists at the Naval Research Laboratory have been using molecular beam epitaxy techniques to grow a variety of high quality magnetic transition metal (TM) films and superlattices having TM thicknesses in the 1–10 monolayer regime. The magnetic and structural properties of these samples have been studied with a wide variety of standard and spin-sensitive techniques, both in vacuo and, when suitably protected, in air. The magnetic behavior of the materials is strongly modified as the TM layers become ultrathin. This work is illustrated with examples involving ultrathin Fe layers on Ag(001), Fe/Ag(001) superlattices containing ultrathin Fe layers, and bcc Co on GaAs(110).
Structural design and mitigation of mirror deformations in lunar-based telescopes

Structural design and analysis of the optical systems for lunar-based telescopes is a challenging task. A driving concern of the Lunar Ultraviolet Telescope Experiment (LUTE) preliminary design study was the degradation of the LUTE optical figure due to thermal deformations, during a temperature cycle of 65 to 265 K at the reference 40 deg latitude, 0 deg longitude landing site. In addressing this task, temperature effects were characterized, and primary-mirror thermal deformations calculated for use in the optical analyses. Trade studies evaluated the qualitative performance of various design schemes. Results indicated that statically determinate mirror supports with bottom-mounted flexures created less optical disturbance under thermal loading than mirror supports at the inner or outer periphery. Another trade indicated that a telescope`s baseplate must be athermalized with respect to the mirrors by matching thermal distortion coefficients. A comparison of three materials for the primary mirror predicted that silicon carbide would be the best material for resisting thermally induced figure deformations on the moon. 15 refs.
DISTRIBUTION OF WATER VAPOR IN MOLECULAR CLOUDS

We report the results of a large-area study of water vapor along the Orion Molecular Cloud ridge, the purpose of which was to determine the depth-dependent distribution of gas-phase water in dense molecular clouds. We find that the water vapor measured toward 77 spatial positions along the face-on Orion ridge, excluding positions surrounding the outflow associated with BN/KL and IRc2, display integrated intensities that correlate strongly with known cloud surface tracers such as CN, C2H, 13CO J = 5-4, and HCN, and less well with the volume tracer N2H+. Moreover, at total column densities corresponding to A V< 15 mag, the ratio of H2O to C18O integrated intensities shows a clear rise approaching the cloud surface. We show that this behavior cannot be accounted for by either optical depth or excitation effects, but suggests that gas-phase water abundances fall at large A V. These results are important as they affect measures of the true water-vapor abundance in molecular clouds by highlighting the limitations of comparing measured water-vapor column densities with such traditional cloud tracers as 13CO or C18O. These results also support cloud models that incorporate freeze out of molecules as a critical component in determining the depth-dependent abundance of water vapor.
UBVI CCD PHOTOMETRY OF THE OLD OPEN CLUSTER BERKELEY 17

Photometric UBVI CCD photometry is presented for NGC 188 and Berkeley 17. Color-magnitude diagrams (CMDs) are constructed and reach well past the main-sequence turnoff for both clusters. Cluster ages are determined by means of isochrone fitting to the cluster CMDs. These fits are constrained to agree with spectroscopic metallicity and reddening estimates. Cluster ages are determined to be 7.0 ? 0.5 Gyr for NGC 188 and 10.0 ? 1.0 Gyr for Berkeley 17, where the errors refer to uncertainties in the relative age determinations. These ages are compared to the ages of relatively metal-rich inner halo/thick-disk globular clusters and other old open clusters. Berkeley 17 and NGC 6791 are the oldest open clusters, with ages of 10 Gyr. They are 2 Gyr younger than the thick-disk globular clusters. These results confirm the status of Berkeley 17 as one of the oldest known open clusters in the Milky Way, and its age provides a lower limit to the age of the Galactic disk.
Ares Launch Vehicle Transonic Buffet Testing and Analysis Techniques

It is necessary to define the launch vehicle buffet loads to ensure that structural components and vehicle subsystems possess adequate strength, stress, and fatigue margins when the vehicle structural dynamic response to buffet forcing functions are considered. In order to obtain these forcing functions, the accepted method is to perform wind-tunnel testing of a rigid model instrumented with hundreds of unsteady pressure transducers designed to measure the buffet environment across the desired frequency range. The buffet wind-tunnel test program for the Ares Crew Launch Vehicle employed 3.5 percent scale rigid models of the Ares I and Ares I-X launch vehicles instrumented with 256 unsteady pressure transducers each. These models were tested at transonic conditions at the Transonic Dynamics Tunnel at NASA Langley Research Center. The ultimate deliverable of the Ares buffet test program are buffet forcing functions (BFFs) derived from integrating the measured fluctuating pressures on the rigid wind-tunnel models. These BFFs are then used as input to a multi-mode structural analysis to determine the vehicle response to buffet and the resulting buffet loads and accelerations. This paper discusses the development of the Ares I and I-X rigid buffet model test programs from the standpoint of model design, instrumentation system design, test implementation, data analysis techniques to yield final products, and presents normalized sectional buffet forcing function root-mean-squared levels.
Stereo- and Regioselectivity of Reactions of Siliranes with Aldehydes and Related Substrates

Siliranes undergo stereoselective and regioselective insertions of benzaldehyde to provide oxasilacyclopentane products. The thermal reaction (>100 °C) leads to more decomposition and side products, whereas the catalyzed variant (t-BuOK, 95%). Treatment of siliranes with enolizable aldehydes leads to silyl enol ethers. The reaction of a silirane at high temperatures with an imine leads to reductive dimerization, presumably by way of intermediate-free silylene. The mechanism for the catalyzed insertion of benzaldehyde is discussed.
Universal GRB Jets from Jet-Cocoon Interaction in Massive Stars

We consider the time-dependent evolution of a relativistic jet following its breakout through the surface of a massive compact star, as envisaged in the collapsar model of gamma-ray bursts. At breakout, the jet is tightly collimated by the pressure of its hot cocoon, which is created as the jet traverses the star. After breakout, the cocoon pressure drops, and the jet expands toward its natural opening angle. We show that the evolving opening angle of the jet produces a stratification of the total energy with the off-axis angle, resulting in a universal morphology. The angular structure is largely independent of the initial beam pattern and depends only on the luminosity of the central engine. With the minimal assumption of a constant energy release we reproduce the θ-2 profile required to explain observations of afterglows.
On the long-period lunisolar effect in the motion of the artificial satellite

This article contains two systems of formulas for the determination of the long-period perturbations caused by the sun and the moon in the motion of an artificial satellite. The first system can be used for the determination of the lunar effect for all satellites. The second method is more convenient for finding the lunar effect for close satellites and the solar effect for all satellites. The knowledge of these effects is essential for the determination of the stability of the orbit of the satellite. The basic equations of both systems are arranged in a form that permits the use of numerical integration. The two theories are more accurate and more adaptable to the use of electronic machines than are the analytical developments obtained previously.
Lifetime of Imidazolium Salts at Elevated Temperatures

This report summarizes progress to date on the thermal stability of imidazolium salts being considered for application as heat transfer and thermal storage fluids in solar parabolic trough power systems. Imidazolium salts are a subset of the general class of molten salts. They are termed ionic liquids because many have freezing points at or below room temperature. This class of salts was selected for initial study because there were many examples that were reported to be stable at high temperatures. These reports were usually based on the results of standard thermal gravimetric analysis (TGA) methods. Work by our subcontractor at the University of Alabama and at NREL showed that slow heating rates or when the temperature is held constant for long times resulted in decomposition temperatures that are much lower than those found with the usual TGA methods. We have used a TGA technique that allows calculation of the rates of thermal decomposition as a function of temperature. The results lead us to the conclusion that the imidazolium salts known to be the most thermally stable would not have useful lifetimes above about 200°C. At present this determination is based on the rough approximation that the fluid in a solar trough system experiences a constant, high temperature. Better estimates of the useful lifetime will require a system model that takes into account the time at temperature distribution of a fluid moving through the different components in a solar plant.
Preparation of 3-amino-1,4-benzodiazepin-2-ones via direct azidation with trisyl azide

Abstract An efficient synthesis of 3-amino-1,4-benzodiazepin-2-ones utilizing triisopropylbenzenesulfonyl azide (trisyl azide) for the direct azidation of 1,4-benzodiazepin-2-ones is described.
Nontrivial velocity distributions in inelastic gases

We study spatially homogeneous inelastic gases using the Boltzmann equation. We consider uniform collision rates and obtain analytical results valid for arbitrary spatial dimension d and arbitrary dissipation coefficient . In the unforced case, we find that the velocity distribution decays algebraically, P(v,t)~v-σ, for sufficiently large velocities. The exponent σ(d,) exhibits nontrivial dependence on the spatial dimension and the dissipation coefficient.
The JPDAF in practical systems: approximations

In this paper we look at various algorithms for approximating the target-measurement association probabilities of the Joint Probabilistic Data Association Filter (JPDAF). We consider their computational complexity and compare their performance with respect to the Mean Optimal Subpattern Assignment (MOSPA) statistic in a scenario involving closely-spaced targets.
Aryl ketone synthesis via tandem orthoplatinated triarylphosphite-catalyzed addition reactions of arylboronic acids with aldehydes followed by oxidation

Tandem orthoplatinated triaryl phosphite-catalyzed addition reactions of arylboronic acids with aldehydes followed by oxidation to yield aryl ketones is described. 3-Pentanone was identified as a suitable oxidant for the tandem aryl ketone formation reaction. By using microwave energy, aryl ketones were obtained in high yields with the catalyst loading as low as 0.01%.
Packet voice communicatins over PC based local area networks

This paper presents actual implementations of packet voice communication systems over two types of PC based local area networks. One is a token-passing ring network and the other is an Ethernet network. The system configuration, system operation and system performance analysis is described for both networks. A formula for the maximum allowable number of active voice stations is presented for both systems.The last part of the paper describes a proposed design for a distributed packet voice communications protocol. The protocol presented deals with the higher levels of the communication system. The purpose of the protocol is to establish and maintain a telephone conversation between two users by using the underlying network services.
On the flexibility of allylic azides as synthetic intermediates

Summary Asymmetric synthesis of an allylic azide combined with the facility of the [3.3]sigmatropic rearrangement provides a simple strategy for the synthesis of conduramine E.
The future of amorphous silicon photovoltaic technology

Amorphous silicon modules are commercially available. They are the first truly commercial thin-film photovoltaic (PV) devices. Well-defined production processes over very large areas (>1 m{sup 2}) have been implemented. There are few environmental issues during manufacturing, deployment in the field, or with the eventual disposal of the modules. Manufacturing safety issues are well characterized and controllable. The highest measured initial efficiency to date is 13.7% for a small triple-stacked cell and the highest stabilized module efficiency is 10%. There is a consensus among researchers, that in order to achieve a 15% stabilized efficiency, a triple-junction amorphous silicon structure is required. Fundamental improvements in alloys are needed for higher efficiencies. This is being pursued through the DOE/NREL Thin-Film Partnership Program. Cost reductions through improved manufacturing processes are being pursued under the National Renewable Energy Laboratory/US Department of Energy (NREL/DOE)-sponsored research in manufacturing technology (PVMaT). Much of the work in designing a-Si devices is a result of trying to compensate for the Staebler-Wronski effect. Some new deposition techniques hold promise because they have produced materials with lower stabilized defect densities. However, none has yet produced a high efficiency device and shown it to be more stable than those from standard glow dischargemore » deposited material.« less
Analysis of polycyclic aromatic hydrocarbon metabolites in cow's milk by liquid–liquid extraction and synchronous room-temperature fluorescence spectroscopy

We present the first application of synchronous room-temperature fluorescence spectroscopy to the analysis of monohydroxy-polycyclic aromatic hydrocarbons in milk samples. Metabolites are extracted from milk samples by a two-step liquid–liquid extraction procedure. The small sample (400 μl) and extracting solvent (1.4 ml) volumes facilitate the simultaneous extraction of numerous samples via an environmentally friendly procedure, which is well-suited for routine monitoring of numerous samples. Quantitative analysis is carried out in the sample extract without the need for previous chromatographic separation. Excellent recoveries and limits of detection at the parts-per-billion level were obtained for 2-hydroxyfluorene, 6-hydroxychrysene, 1-hydroxypyrene and 3-hydroxybenzo[a]pyrene. The non-destructive nature of the new method provides ample opportunity for metabolite confirmation via chromatographic techniques.
Preparation of Ethyl 5-Iodo-1H-indole- 2-carboxylate

A facile, two step procedure for the preparation of ethyl 5-iodo-1H-indole-2-carboxylate (1) from commercially available ethyl 1H-indole-2-carboxylate is described herein, employing a regioselective C3, C5-bisiodination followed by zinc-mediated C3-dehalogenation.
ECONOMIC EVALUATION AND OPTIMIZATION OF SOLAR HEATING SYSTEMS

A procedure is developed for assessing the economic viability of a solar heating system in terms of the life cycle savings of a solar heating system over a conventional heating system. The life cycle savings is expressed in a generalized formby introducing two economic parameters, P1 and P2, which relate all life cycle cost considerations to the first year fuel cost or the initial solar system investment cost. Using the generalized life cycle savings equation, a method is developed for calculating the solar heating system design which maximizes the life cycle savings. A similar method is developed for determining the set of economic conditions at which the optimal solar heating system design is just competitive with the conventional heating system. The results of these optimization methods can be presented in tabular or graphical form. The sensitivity of the economic evaluation and optimization calculations to uncertainties in constituent thermal and economic variables is also investigated.
Connectivity properties of a packet radio network model

A model of a packet radio network in which transmitters with range R are distributed according to a two-dimensional Poisson point process with density D is examined. To ensure network connectivity, it is shown that pi R/sup 2/D, the expected number of nearest neighbors of a transmitter, must grow logarithmically with the area of the network. For an infinite area there exists an infinite connected component with nonzero probability if pi R/sup 2/D>N/sub 0/, for some critical value N/sub 0/. It is shown that 2.195 >
Diazirines in carbenoid reactions catalyzed by rhodium(II) carboxylates

Abstract Diazo compounds formed by thermal or photolytic rearrangement of 3-alkyl-3-phenyl-diazirines in the presence of catalytic amounts of rhodium(II) perfluorobutyrate are effectively directed to metal carbenoid products with minimal competition from processes which are dominant when the diazo compound is used directly or when the diazirine is decomposed in the absence of the catalyst.
The design of a corporate planning system simulator

The integration of various functional activities in an organization can be accomplished by using a hierarchical data model based on the firms chart of accounts. Viewing the entire accounting system as a schema and the information requirements of each decision-making unit as a subschema, modularity in planning can be achieved. Once the total configuration of the system and the accounting transactions are stored in a data base, a simpler planning language can be developed to simulate the performance of the total system or any subsystem.
Determination of a new structure type in the Sc–Fe–Ge–Sn system

Abstract A new structure type has been discovered in the system Sc–Fe–Ge–Sn by employing Sn as a flux medium. According to single crystal X-ray diffraction, the new structure has a composition of Sc4Fe5Ge6.10(3)Sn1.47(2) and crystallizes in the space group Immm (No. 71, oI144) with lattice parameters of a = 5.230(1) A, b = 13.467(3) A, and c = 30.003(6) A. The structure is composed of square anti-prismatic clusters that are condensed into zig-zag chains along the [0 1 0] direction. These chains are further condensed through a split Sn/Ge position, forming a three-dimensional network. Magnetization measurements indicate an antiferromagnetic phase transition near 240 K. Electronic structure calculations identified the most favorable bonding network in this new system. Using crystal orbital Hamilton population (COHP) curves and their integrated values (ICOHP), a polar intermetallic bonding network involving Sc–Ge as well as Fe–Sn and Fe–Ge contacts can be assigned to this new structure type.
An X-Ray Temperature Map of the Merging Cluster Abell 2255

We present a spatially resolved map of intracluster gas temperatures in the rich cluster Abell 2255, using ROSAT PSPC data. The intracluster gas is strongly nonisothermal and the temperature distribution supports the conclusions of Burns and coworkers that Abell 2255 is currently undergoing a merger. The hottest regions are near the core, northwest of the center. A map of the ratio of softer to harder X-ray photons reveals an anomalously soft region northeast of the center, coincident with a radio ridge discovered by Burns and coworkers in 1995. We suggest that this cooler region is associated with an infalling group of galaxies that is giving rise to the radio ridge. Meanwhile, a much more substantial recent merger between comparably sized subcluster components can account for the more global merger signatures, which include the extensive central radio halo, the large-scale gas temperature variations, the pair of central-dominant ellipticals, elliptical X-ray isophotes offset from these dominant galaxies, and the very high velocity dispersion of galaxies in the cluster.
Resistance across an interface, and that measured far from it

We solve the linearized Boltzmann equation for currents perpendicular to the planes of the layers for two semi-infinite metallic layers in the presence of diffuse and specular scattering at the interface. In particular, the variation of chemical potential within a mean-free path of the interface is investigated. The difference between the potential drop associated with the interface farfrom it and that at the interface depends on the amount of diffuse scattering and can change sign. In the case of the same metal from both sides of the boundary, we classify different forms of diffuse scattering according to whether the measured resistance is bigger or smaller than that across the interface. For certain forms of diffuse scattering, the chemical potential remains constant outside the interfacial region. We show that the interface resistance in the presence of the diffuse scattering in the bulk of the layers is less than that calculated in the ballistic transport regime. For the Cr-Fe system, we calculate the difference between interface resistance of the majority and minority electrons as a function of the amount of diffuse scattering at the interface, and show that this difference, relative to the interface resistance of the majority electrons, grows as the amount of diffuse scattering decreases.
Aperiodic dynamics and the self-organization of cognitive maps in autonomous agents

When we look at the dynamics produced by biological neuronal populations, we are immediately struck by the fact that aperiodic, chaotic-like dynamics appear to be the normal operating state of such systems. Recent work has shown that such aperiodic dynamics, at least in perceptual systems, may not only be the result of random perturbations experienced by the system from external stimulation, but that the brain itself generates aperiodic dynamics to deal more flexibly and reliably with noisy environmental stimulation. Complex systems concepts are helping us to understand the properties of nonlinear systems that are fundamental for the emergence of complex spatiotemporal patterns in natural and biological systems. Advances in neuroscience and computational neurodynamics are applying these concepts of self-organization to understanding the spatiotemporal patterns observed in biological brains. In this article, we introduce a neural population model that is capable of replicating the generation of these types of aperiodic dynamics observed in biological brains. We use the model to self-organize cognitive maps in an autonomous agent through the agent's interaction with its environment. We show how such high-dimensional spatiotemporal dynamics may be shaped by environmental input and learning to form chaotic attractors that come to represent “meanings” for the agent. We discuss how the internal generation of such aperiodic dynamics may aid in the formation and recognition of such noisy environmental stimuli in biological organisms in general and in our simulated agents specifically. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 955–971, 2006.
The Effects of Prior Beliefs and Learning on Consumers' Acceptance of Genetically Modified Foods

Abstract New food products using genetically modified crops appeared in U.S. supermarkets starting in 1996, and consumers’ perceived some risks. This paper examines the role of consumers prior beliefs about genetic modification and of diverse, new information on their willingness to pay for foods that might be genetically modified. We use data from economics experiments and show that participants who had informed prior beliefs discounted GM-labeled food products more highly than those who had uninformed prior beliefs. Uninformed participants were especially susceptible to information from interested and third parties. In contrast, informed participants were generally not affected significantly by new information.
Z-Selective ring opening of vinyl oxetanes with dialkyl dithiophosphate nucleophiles

Dialkyl dithiophosphates selectively ring open vinyl oxetanes in excellent yields under mild reaction conditions to form useful allylic thiophosphate products with high Z-selectivity.
Structure and dynamics in modified electrodes

Abstract Modified electrodes are usually created either to facilitate the delivery of charge from an electrode to a substrate in solution or to transfer information within themselves. Thus they are intended for dynamic purposes. In this paper, the elements of dynamics in modified electrodes are reviewed. Emphasis is placed on the influence of microstructure on these elements, particularly on the diffusivities of the substrate and the electrons within a modifying layer. The effective diffusion of electrons is critical to the success of most modifying layers thicker than a monolayer. Ideas about the manner in which this process can occur are explored and their experimental implications are discussed. The concepts are illustrated with results from this laboratory.
Ferromagnetic Resonance Linewidth in Cobalt-Substituted Ferrites

The effect of small concentrations of substitutional ions on the ferromagnetic resonance linewidth of a host ferrite is calculated. The resonance linewidth arises from magnon scattering induced by the variation from ion-to-ion of the spin-orbit interaction. This interaction is uniquely large for cobalt ions because of the orbital degeneracy of the ground state of the ion in a trigonally-symmetric crystalline field. The resultant contribution to the linewidth is found to be isotropic and of the order of 20-30 oersteds for each percent of cobalt in normal (i.e., noninverse) ferrites or in ferrous ferrite. In other ferrites the effect is diminished by the lifting of the ground-state orbital degeneracy at some of the cobalt sites; this diminution is calculated as a function of the degree of inversion.
Weak approximation for linear systems of quadrics

We give local conditions at ∞ ensuring that the intersection of n quadrics in PN, N≫n, satisfies weak approximation.
Inductively coupled high-density plasma-induced etch damage of GaN MESFETs

Abstract The fabrication of a wide variety of GaN-based photonic and electronic devices depends on dry etching, which typically requires ion-assisted removal of the substrate material. Under conditions of both high plasma flux and energetic ion bombardment, GaN etch rates greater than 0.5 μm min −1 and anisotropic etch profiles are readily achieved in inductively coupled plasma (ICP) etch systems. Unfortunately, under these conditions, plasma-induced damage often occurs. Attempts to minimize such damage by reducing the ion energy or increasing the chemical activity in the plasma often result in a loss of etch rate or profile control which can limit dimensional control and reduce the utility of the process for device applications requiring anisotropic etch profiles. It is therefore necessary to develop plasma etch processes which couple anisotropy for critical dimension and sidewall profile control and high etch rates with low-damage for optimum device performance. In this study, we report changes in source resistance, reverse breakdown voltage, transconductance, and drain saturation current for GaN MESFET structures exposed to an Ar ICP plasma. In general, plasma-induced damage was more sensitive to ion bombardment energies as compared to plasma flux.
Duality, quantum vortices and anyons in Maxwell-Chern-Simons-Higgs theories

Abstract The order-disorder duality structure is exploited in order to obtain a quantum description of anyons and vortices in: (a) the Maxwell theory; (b) the Abelian Higgs model; (c) the Maxwell-Chern-Simons theory; (d) the Maxwell-Chem-Simons-Higgs theory. A careful construction of a charge bearing order operator (σ) and a magnetic flux bearing disorder operator (vortex operator) (μ) is performed, paying attention to the necessary requirements for locality. An anyon operator is obtained as the product φ = σμ. A detailed and comprehensive study of the euclidean correlation functions of σ, μ, and φ is carried on in the four theories above. The exact correlation functions are obtained in cases a and c. The large distance behavior of them is obtained in cases b and d. The study of these correlation functions allows one to draw conclusions about the condensation of charge and magnetic flux, establishing thereby an analogy with the Ising model. The mass of vortex and anyon excitations is explicitly obtained wherever these excitations are present in the spectrum. The independence between the mechanisms of mass generation for the vortices and for the vector field is clearly exposed.
Public Information and Electoral Bias

Abstract We present a theory of voting that predicts that elections are more likely to be close, and voter turnout is more likely to be high when citizens possess better public information about the composition of the electorate. These findings suggest that providing more information to potential voters about aggregate political preferences (e.g., through pre-election polls or expert forecasts) may undermine the democratic process. Our analysis reveals that if the distribution of political preferences is common knowledge, then the unique type-symmetric equilibrium leads to a stark neutrality result in which each alternative is equally likely to win the election. By contrast, when citizens are ignorant about the preference distribution, the majority is more likely to win the election and expected voter turnout is lower. Welfare is, therefore, unambiguously higher when citizens possess less information about the preference distribution.
The effect of education on religion: Evidence from compulsory schooling laws

Abstract For over a century, social scientists have debated how educational attainment impacts religious belief. In this paper, I use Canadian compulsory schooling laws to identify the relationship between completed schooling and later religiosity. I find that higher levels of education lead to lower levels of religious affiliation later in life. An additional year of education leads to a 4-percentage-point decline in the likelihood that an individual identifies with any religious tradition. This is a reasonably large effect: extrapolating the results to the broader population would suggest that increases in schooling could explain most of the large rise in non-affiliation in Canada in recent decades.
Quenching of weak interactions in nucleon matter

We have calculated the one-body Fermi and Gamow-Teller charge-current and vector and axial-vector neutral-current nuclear matrix elements in nucleon matter at densities of 0.08, 0.16, and $0.24{\mathrm{fm}}^{\ensuremath{-}3}$ and proton fractions ranging from 0.2 to 0.5. The correlated states for nucleon matter are obtained by operating on Fermi-gas states by a symmetrized product of pair correlation operators determined from variational calculations with the Argonne-v18 and Urbana-IX two- and three-nucleon interactions. The squares of the charge- current matrix elements are found to be quenched by 20\char21{}25 % by the short-range correlations in nucleon matter. Most of the quenching is due to spin-isospin correlations induced by the pion exchange interactions which change the isospins and spins of the nucleons. A large part of it can be related to the probability for a spin-up proton quasiparticle to be a bare spin-up/down proton/neutron. Within the interval considered, the charge-current matrix elements do not have significant dependence on the matter density, proton fraction, and magnitudes of nucleon momenta; however, they do depend on momentum transfer. The neutral-current matrix elements have a significant dependence on the proton fraction. We also calculate the matrix elements of the nuclear Hamiltonian in the same correlated basis. These provide relatively mild effective interactions that give the variational energies in the Hartree-Fock approximation. The calculated two-nucleon effective interaction describes the spin-isospin susceptibilities of nuclear and neutron matter fairly accurately. However terms greater than or equal to three-body terms are necessary to reproduce the compressibility. Realistic calculations of weak interaction rates in nucleon matter can presumably be carried out using the effective operators and interactions studied here. All presented results use the simple two-body cluster approximation to calculate the correlated basis matrix elements. This allows for a clear discussion of the physical effects in the effective operators and interactions.
Preparation and reactions of a disilyne synthon, 7,7′‐bis(7‐methyl‐1,4,5,6‐tetraphenyl‐7‐sila‐2,3‐benzo‐norbornadiene)

The title compound (2) was prepared by condensing a bis(silole) 1 with benzyne. Thermolysis of 2 in the presence of anthracene, 9,10-dimethylanthracene (DMA), 2,3-dimethylbutadiene, and two acetylenes is described in detail. X-ray structures for the anthracene and DMA adducts are reported.
A circuit set characterization of antimatroids

Abstract Antimatroids generalize the notion of convexity in much the same way as matroids generalize the notion of linear dependence. Definitions and examples of antimatroids are presented. Rooted circuits of anitmatroids are defined, and a new characterization of antimatroids is given. This characterization involves a rooted circuit elimination property that is reminiscent of the matroid circuit elimination property.
Maximum screening fields of superconducting multilayer structures

It is shown that a multilayer comprised of alternating thin superconducting and insulating layers on a thick substrate can fully screen the applied magnetic field exceeding the superheating fields Hs of both the superconducting layers and the substrate, the maximum Meissner field is achieved at an optimum multilayer thickness. For instance, a dirty layer of thickness ∼0.1 μm at the Nb surface could increase Hs ≃ 240 mT of a clean Nb up to Hs ≃ 290 mT. Optimized multilayers of Nb3Sn, NbN, some of the iron pnictides, or alloyed Nb deposited onto the surface of the Nb resonator cavities could potentially double the rf breakdown field, pushing the peak accelerating electric fields above 100 MV/m while protecting the cavity from dendritic thermomagnetic avalanches caused by local penetration of vortices.
Simulation of hypersonic flows using a detailed nitric oxide formation model

In this paper the extensive quasiclassical trajectory (QCT) study recently concluded [J. Chem. Phys. 104, 2825 (1996)] is used to model the kinetics of the primary NO formation reaction, N2+O→NO+N, in hypersonic nonequilibrium flows. The QCT data are used to obtain expressions for the thermal rate constant, reactant energy removal, and product energy disposal rates of this reaction. The QCT results are coupled with the continuum conservation flow equations, and these equations are used to simulate the Bow-Shock UltraViolet2 (BSUV2) flow at altitudes between 75 to 87.5 km. It is found that the use of the Macheret and Rich [Chem. Phys. 174, 25 (1993)] vibration–dissociation coupling model along with the QCT rates gives improvements in the NO concentration predictions at altitudes between 80 and 85 km. Also, it is found that the vibrational and rotational temperatures of NO are much higher than that of the N2 and O2 in the gas, in accordance with the BSUV2 measurements. The amount of NO produced in the flow fields at 87.5 km and above is found to be strongly dependent on the free-stream density of atomic oxygen.