Nuclear Data Sheets for A = 116

The 1960 version of the Nuclear Data Sheets for A = 116 has been revised on the basis of experimental data received before August 1973, with some later modifications received via private communications. Experimental data concerning the nuclear structure of ten isotopes were compiled and used in the construction of the level schemes and J^π-assignments.     

Synthesis and characterization of poly(keto-amines). 1. Self polycondensation of 4-aminophenacyl chloride

Novel poly(keto-amines), designated as poly(4-iminophenacyls) are prepared by self polycondensation of 4-aminophenacyl chloride under different experimental conditions. These polymers are insoluble in common solvents. The number average molecular weights of the polymer samples have been estimated by conductometric titration of a suspension of the polymer sample in formic acid against a standard perchloric acid. The polymer samples have been characterized by a comparative study of their IR spectra with those of the probable model compounds and by differential thermogravimetric analysis.     

Statistical models for renal micropuncture studies

Statistical issues relating to data analysis of re-collection micropuncture experiments are presented. In the presence of significant animal-treatment interaction, namely, differential response of each animal at different levels of the treatment, the conventional paired or unpaired t testing would not be entirely appropriate. Accordingly, two analysis of variance (ANOVA) models have been derived for the appropriate paired and unpaired designs of micropuncture experiments. Interactive computer programs have been written for both these analyses, and the results are illustrated with experimental data. An example is presented in which the results are statistically significant with paired t testing and by analysis of variance for unequal number of tubules but not when the animal-treatment interaction is included in the analysis of variance model. To investigate linkage in renal transport mechanisms, we propose the use of partial correlation analysis. Experimental results from our laboratory are used to illustrate these techniques.     

Optimization of multi-cell wings for strength and natural frequency requirements

The present work determines the optimal number of cells for minimum weight design of an aircraft wing under strength and natural frequency constraints for the two cases (i) uniform loading and (ii) a tip moment. Two SUMT optimization algorithms with and without parameters have been used and suggestions for faster convergence for one have been given. The importance of different starting design points and convergence criteria in getting the constrained minimum has been shown. The variables considered are length, chord, skin thickness and various spar thicknesses. The natural frequency has been obtained by the use of exact continuum theory of cylindrical tubes, and comparison with elementary theory has been made. The optimization results indicate that increasing the number of cells beyond two does not lead to any substantial reduction or increase in weight. Also, stringent convergence criterion and more than one starting point are necessarry for better results.     

Cognitive Radio and Networking Research at Virginia Tech

More than a dozen Wireless @ Virginia Tech faculty are working to address the broad research agenda of cognitive radio and cognitive networks. Our core research team spans the protocol stack from radio and reconfigurable hardware to communications theory to the networking layer. Our work includes new analysis methods and the development of new software architectures and applications, in addition to work on the core concepts and architectures underlying cognitive radios and cognitive networks. This paper describes these contributions and points towards critical future work that remains to fulfill the promise of cognitive radio. We briefly describe the history of work on cognitive radios and networks at Virginia Tech and then discuss our contributions to the core cognitive processing underlying these systems, focusing on our cognitive engine. We also describe developments that support the cognitive engine and advances in radio technology that provide the flexibility desired in a cognitive radio node. We consider securing and verifying cognitive systems and examine the challenges of expanding the cognitive paradigm up the protocol stack to optimize end-to-end network performance. Lastly, we consider the analysis of cognitive systems using game theory and the application of cognitive techniques to problems in dynamic spectrum sharing and control of multiple-input multiple-output radios.     

Chemical‐looping combustion — an overview and application of the recirculating fluidized bed reactor for improvement

This paper propose recirculating fluidized bed (RCFB) reactor for chemical‐looping combustion (CLC) to overcome some of the issues associated with the existing interconnected reactors arrangements like low residence time of bed material in the air reactor, high attrition of bed material in the cyclone separator, cluster formation in the air reactor, complex operation involving loop seals and high heat losses. RCFB has high solid circulation rate, long residence time, efficient fuel–oxygen carrier contact, low heat losses and low gas leak in between the reactors, as compared to the existing reactor configurations. A cold model study was performed on a Perspex made, semicircular, transparent RCFB reactor. A single RCFB reactor was operated in the alternate oxidation and fuel burning cycles to simulate the interconnected reactors arrangement for CLC. The generated experimental data has been used to predict the optimal RCFB reactor configuration for a RCFB‐based CLC power plant. Copyright © 2014 John Wiley & Sons, Ltd.     

Plasma Start-up in HIT-II and NSTX Using Transient Coaxial Helicity Injection

The method of transient coaxial helicity injection (CHI) has previously been used in the HIT-II experiment at the University of Washington to produce 100 kA of closed flux current. The generation of the plasma current by CHI involves the process of magnetic reconnection, which has been experimentally controlled in the National Spherical Torus Experiment (NSTX) at the Princeton Plasma Physics Laboratory to allow this potentially unstable phenomenon to reorganize the magnetic field lines to form closed, nested magnetic surfaces carrying a plasma current up to 160 kA. This is a world record for non-inductive closed-flux current generation, and demonstrates the high current capability of this method.     

Flame-retardant properties of in situ sol-gel synthesized inorganic borosilicate/silicate polymer scaffold matrix comprising ionic liquid

This paper focuses on the superiority of organic-inorganic hybrid ion-gel electrolytes for lithium-ion batteries (LiBs) over commercial electrolytes, such as 1 M LiPF₆ in 1:1 ethylene carbonate (EC): dimethyl carbonate (DMC) {1 M LiPF₆-EC: DMC}, in terms of their flame susceptibility. These ion-gel electrolytes possess ionic liquid monomers, which are confined within the borosilicate or silicate matrices that are ideal for non-flammability. Naked flame tests confirm that the organic-inorganic hybrid electrolytes are less susceptible to flames, and these electrolytes do not suffer from a major loss in terms of weight. In addition, the hybrids are self-extinguishable. Therefore, these hybrids are only oxidized when subjected to a flame unlike other commercial electrolytes used in lithium-ion batteries. Supplementary analyses using differential scanning calorimetric studies reveal that the hybrids are glassy until the temperature reaches more than 100°C. The current results are consistent with previously published data on the organic-inorganic hybrids.     

Model algorithmic control (MAC); basic theoretical properties

A mathematical framework for the analysis of model algorithmic control is developed and the operations of the main components of the control structure are described. The single input-single output case is treated in detail and results pertaining to the stability and the robustness of such systems are derived, both for deterministic and stochastic (colored output additive noise) environment. The case of the nonminimum phase plant is also considered. The robustness problem is discussed and performance ‘measures’ of robustness are proposed. The results derived in this paper are more generally applicable to optimizing type of control laws. In particular, the paper establishes a close link between the stability and closed loop properties of optimizing type and feedback type of control laws.