Stress-induced structural changes in La-doped BiFeO3–PbTiO3 high-temperature piezoceramics

High-temperature piezoelectric polycrystalline ceramics of the system (1 ? x)(Bi_1?yLa_y)FeO₃-xPbTiO₃ (BF–PT), which are mixed phase in their consolidated state, have been investigated by in situ neutron diffraction during the application of uniaxial compressive stress. It is suggested that the achievable strain in BF–PT is largely generated by straining of the rhombohedral phase. The results of the neutron diffraction measurements are compared and discussed with respect to the measured macroscopic ferroelastic constitutive behavior for various compositions of BF–PT.     

Progress in the development of a high average power ultra-broadbandinfrared radiation source

This paper describes numerical and analytical studies on the optimization of the ultra-broadband infrared (IR) source, a novel high average-power device. The main objective of current studies was the reduction of weight, size, and cost of the system by devising a scheme to generate the two closely spaced radiation lines with a single laser driver instead of the two CO₂ transversely excited atmospheric pressure (TEA) lasers envisioned in the initial work. By inducing the modulation instability in nonlinear media, we have obtained as good or better results as in our previous studies but with one of the TEA lasers replaced by a very low-power driver that provides the seed radiation for the excitation of the instability. Even more importantly, we have demonstrated that the second high peak-power TEA laser can be replaced by a compact, light weight, low peak-power driver by focusing the radiation to a tighter spot. The average power of the source is maintained at the previous level by operating at higher duty factor. In the new low-peak-power operating regime, the output spectrum is very similar to that of the high-power regime, provided that the ratio of the peak power to the nonlinear length that scales proportionally to the area of the laser spot remains fixed     

Experimental and computational mapping of the binding surface of a crystalline protein

Multiple Solvent Crystal Structures (MSCS) is a crystallographictechnique to identify energetically favorable positions andorientations of small organic molecules on the surface of proteins.We determined the high-resolution crystal structures of thermolysin(TLN), generated from crystals soaked in 50–70% acetone,50–80% acetonitrile and 50 mM phenol. The structures ofthe protein in the aqueous–organic mixtures are essentiallythe same as the native enzyme and a number of solvent interactionsites were identified. The distribution of probe molecules showsclusters in the main specificity pocket of the active site anda buried subsite. Within the active site, we compared the experimentallydetermined solvent positions with predictions from two computationalfunctional group mapping techniques, GRID and Multiple CopySimultaneous Search (MCSS). The experimentally determined smallmolecule positions are consistent with the structures of knownprotein–ligand complexes of TLN.     

A principal components analysis of dynamic spatial memory biases.

Research has shown that spatial memory for moving targets is often biased in the direction of implied momentum and implied gravity, suggesting that representations of the subjective experiences of these physical principles contribute to such biases. The present study examined the association between these spatial memory biases. Observers viewed targets that moved horizontally from left to right before disappearing or viewed briefly shown stationary targets. After a target disappeared, observers indicated the vanishing position of the target. Principal components analysis revealed that biases along the horizontal axis of motion loaded on separate components from biases along the vertical axis orthogonal to motion. The findings support the hypothesis that implied momentum and implied gravity biases have unique influences on spatial memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Graphene synthesis by ion implantation

We demonstrate an ion implantation method for large-scale synthesis of high quality graphene films with controllable thickness. Thermally annealing polycrystalline nickel substrates that have been ion implanted with carbon atoms results in the surface growth of graphene films whose average thickness is controlled by implantation dose. The graphene film quality, as probed with Raman and electrical measurements, is comparable to previously reported synthesis methods. The implantation synthesis method can be generalized to a variety of metallic substrates and growth temperatures, since it does not require a decomposition of chemical precursors or a solvation of carbon into the substrate.     

The dyadic nature of social information processing in boys' reactive and proactive aggression.

The correlation between boys' social cognitions and their aggressive behavior toward peers was examined as being actor driven, partner driven, or dyadic relationship driven. Eleven groups of 6 familiar boys each (N?=?165 dyads) met for 5 consecutive days to participate in play sessions and social-cognitive interviews. With a variance partitioning procedure, boys' social-cognitive processes were found to vary reliably across their dyadic relationships. Furthermore, mixed models regression analyses indicated that hostile attributional biases toward a particular peer were related to directly observed reactive aggression toward that peer even after controlling for actor and partner effects, suggesting that these phenomena are dyadic or relationship oriented. On the other hand, the relation between outcome expectancies for aggression and the display of proactive aggression appeared to be more actor driven and partner driven that dyadic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fluorescent tissue site-selective lanthanide chelate, Tb-PCTMB for enhanced imaging of cancer.

In-vivo and in-vitro investigations indicate that a newly developed polyazamacrocyclic chelate of Tb(III) has superior properties for use as an abnormal tissue marker. In addition to tissue selectivity, this molecule is unique because of its low toxicity, attractive fluorescent properties, rapid pharmokinetics, and relatively high water solubility. The complex Tb-3,6,9-tris(methylene phosphonic acid n-butyl ester)-3,6,9,15-tetraazabicyclo[9.3.1]-pentadeca-1(15),11,13 -triene (Tb-PCTMB) has also been shown to exhibit strongly shifted emission (delta lambda--280 nm), moving the detection frequency away from autofluorescence backgrounds, and good quantum efficiencies (phi = 0.51), providing high brightness. Fluorescence imaging was used to quantify Tb-PCTMB at the picomolar level in tissues and to show the significant difference in affinity for the chelate by adenocarcinoma cells HT-29 versus normal epithelial cells (IEC-6). Topical application, or lavage introduction, under endoscopy was used to instill a millimolar aqueous solution of Tb-PCTMB into a dimethylhydrizene-treated Sprague Dawley rat large intestine containing a suspect growth. Subsequent in vitro fluorescence detection and standard histological evaluation confirmed enhanced uptake by adenocarcinoma tissue. Semiquantitative signal interrogation was employed to show the potential for using Tb-PCTMB as a contrast enhancement marker for disease detection.     

The use of simulation modeling and factorial analysis as a method for process flow improvement

Over the past quarter century, much effort has been devoted to the design and development of simulation modeling languages, and to methods for the development of simulation models themselves. Less effort, however, has been expended on the design of the experimental models upon which simulation studies are based. This paper describes a methodology for the determination of near optimal solutions considering experimental design and simulation modeling. Using this methodology, simulation scenarios are created and analyzed using an analysis of variance (ANOVA)-based experimental design. This paper also presents an application of this method in analyzing a manufacturing system design problem.     

Thermal and chemical stabilization of ethylene/vinyl acetate/vinyl alcohol (EVA‐OH) terpolymers under nitroplasticizer environments

In this study, we compare the aging behaviors of cross‐linked ethylene/vinyl acetate/vinyl alcohol terpolymers, also referred to as EVA‐OH, when they are either immersed in nitroplasticizer (NP) liquid or exposed to NP vapor at different temperatures. While thermogravimetric analysis and differential scanning calorimetry are used to probe the thermal stability of aged NP and polymers, Fourier transform infrared, gel permeation chromatography, ultra‐violet/vis, and nuclear magnetic resonance are used to probe their structural changes over the aging process. The study confirms that NP degrades through C? N cleavage, and releases HONO molecules at a slightly elevated temperature (<75°C). As these molecules accumulate in the vapor phase, they react among themselves to create an acidic environment. Therefore, these chemical constituents in the NP vapor significantly accelerate the hydrolysis of EVA‐OH polymer. When the hydrolysis occurs in both vinyl acetate and urethane groups and the scission at the cross‐linker progresses, EVA‐OH becomes vulnerable to further degradation in the NP vapor environment. Through the comprehensive characterization, the possible degradation mechanisms of the terpolymers are proposed. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41450.     

Tea seed oil—A test for its detection in olive oil

The test presented permits detection of as little as 5% of tea seed oil in 95% olive oil. Cottonseed oil or sesame oil interfere with the test. The interference of sesame oil can be overcome to a great extent through the modification recommended. Rancid olive oil interferes with the test. Heated oils may interfere. However, such oils are not likely to be present in olive oil sold for food purposes.