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Many attractors are found in Chua’s oscillator by varying the parameters. Figure 2 shows a geometric model of Chua’s double-scroll chaotic attractor which is observed in Chua’s oscillator. By coupling several Chua’s oscillators in an array even more complicated phenomena can be observed. Figure 6 a shows spiral waves and target waves interacting in an array of Chua’s oscillators. Figure 6 b shows a Turing pattern which is observed in an array of Chua’s oscillators.
Hydroxycinnamate coenzyme A (CoA) thioesters are substrates for biosynthesis of lignin and hydroxycinnamate esters of polysaccharides and other polymers. Hence, a supply of these substrates is essential for investigation of cell wall biosynthesis. In this study, three recombinant enzymes, caffeic acid 3-O-methyltransferase, 4-coumarate-CoA ligase 1, and 4-coumarate-CoA ligase 5, were cloned from wheat, tobacco, and Arabidopsis, respectively, and were used to synthesize 14C-feruloyl-CoA, caffeoyl-CoA, p-coumaroyl-CoA, feruloyl-CoA, and sinapoyl-CoA. The corresponding hydroxycinnamoyl-CoA thioesters were high-performance liquid chromatography purified, the only extraction/purification step necessary, with total yields between 88â95%. Radiolabeled 14C-feruloyl-CoA was generated from caffeic acid and S-adenosyl-14C-methionine under the combined action of caffeic acid 3-O-methyltransferase and 4-coumarate-CoA ligase 1. About 70% of 14C-methyl groups from S-adenosyl methionine were incorporated into the final product. The methods presented are simple, fast, and efficient for the preparation of the hydroxycinnamate thioesters.
Many highly nonlinear devices have been invented over the past two decaded and are becoming increasingly important in the design of modern electronic systems. The behaviors of these systems can be extremely complex and any circuit theory for analyzing such exotic phenomena must necessarily be nonlinear. In particular, some recent research on the modeling of nonlinear devices has demonstrated the dire need for developing a foundation for nonlinear circuits.
We describe the construction and operation of a liquid-phase reaction cell designed in our laboratory that is attached to an ultrahigh-vacuum (UHV) chamber equipped with the traditional surface science techniques for structure and composition analysis. The sample surface can be prepared and characterized in the UHV chamber prior to transfer in the liquid-phase reaction cell. The transfer has been designed so that there is no loss of the UHV chamber vacuum integrity, as few parts as possible come into contact with the liquid, the surface stays clean during the transfer. The liquid-phase reaction cell itself is designed to study liquid-phase hydrogenation reactions at pressures up to 2 atm and temperatures up to 70 °C. A 1-mm-diam liquid jet with a velocity up to 6 m/s is produced by a gear pump that is incident on the sample surface to allow good mass transfer at the liquid-solid interface. The progress of the reaction is followed by gas chromatography. We report the reaction rate data for the hydrogenation of cyclohexene on a platinum foil.
The controlled functionalization of polystyrene using a process of metalation with a potassium superbase followed by reaction with electrophiles is described. The method is advantageous because metalation is extremely efficient, occurring rapidly even at room temperature, and the degree of functionalization can be controlled over a very broad range. Functionalization with trimethylsilyl groups allows effective monitoring and quantification of the metalation process. Other examples of modification include the introduction of small dendritic fragments by reaction with a dendron having an aldehydic focal point or the introduction of carboxylic acid pendant groups. This method, which has little effect on the polydispersity of the polymer, has broad applicability for the functionalization of a wide spectrum of polymers containing active hydrogens and may also be used to prepare randomly branched or star structures.
Hemorrhage in dogs to 30 mm. Hg did not produce platelet aggregation. Significant platelet aggregation was shown in stored blood delivered through the standard blood administration set, in the splanchnic circulation in endotoxic shock, and in the inferior vena cava following three hours of aortic cross-clamping. Pulmonary trapping of platelet aggregates could not be shown by serial screen filtration pressure measurements.
Abstract Durch zyklische Voltammetrie, galvanostatische Aufladung und Gleichgewichts‐ Polarisationsuntersuchungen wird gezeigt, daß sich bei 22°C auf Fe in LiOH zunächst Fe 3 O 4 und Fe(OH) 2 bilden und danach Fe zu 7‐Fe2O3 oder F e(OH)3.
This article seeks to illumine the street-level, internal, meshing of social structure, strategy and experience in the contemporary black American ghetto by dissecting the practices of a professional `hustler' who works the streets of Chicago's South Side. A socioanalytic interpretation of Rickey's life - his background, worldview and social attachments, as well as his techniques of coping and methods of predatory entrepreneuralism - shows how individual strategies of survival at the core of today's `dark ghetto' can aggregate into a trajectory of collective destruction that gives all appearances of being self-inflicted, even as it is (over)determined by the twofold retrenchment of market and state and by the social entropy that these determine. Through an ironic historical reversal, it is whites who, having vanished from the social universe and consciousness of ghetto residents, have become the `invisible men' of the new sociospatial structure of relegation that consigns poor urban blacks to an internecine war with neither victors nor end. The analysis of a single individual lifeworld thus serves to illumine the whole system of material and symbolic relations, visible and invisible, local and societal, that compose the late 20th-century ghetto as instrument of relegation and lived reality.
