Dual nature

It does not provide mueh historieal perspeetive on the development of quantum meehanies. Subjeets sueh as the photoeleetrie effeet, blaek-body radiation, the dual nature of eleetrons and photons, and the Davisson and Germer experiments are not even diseussed. 

The process of designing a pyrotechnic mixture begins with the selection of oxidizer and fuel, and proceeds to incorporate additional components to achieve the exact pyrotechnic effect and bum rate desired in the end item. It is at this point that pyrotechnics takes on the dual nature of an art and science, and experience is often the only thing that can be reHed upon for the solution of a difficult problem. 

Silicates in Solutions. The distribution of sdicate species in aqueous sodium sdicate solutions has long been of interest because of the wide variations in properties that these solutions exhibit with different moduli (23—25). Early work led to a dual-nature description of sdicates as solutions composed of hydroxide ions, sodium ions, coUoidal sdicic acid, and so-called crystaHoidal sdica (26). CrystaHoidal sdica was assumed to be analogous to the simple species then thought to be the components of crystalline sdicate compounds. These include charged aggregates of unit sdicate stmctures and sdica (ionic micelles), and weU-defined sdicate anions. 

Powerforming is basically a conversion process in which catalytically promoted chemical reactions convert low octane feed components into high octane products. The key to a good reforming process is a highly selective dual-function catalyst. The dual nature of this catalyst relates to the two separate catalyst functions atomically dispersed platinum to provide... 

Certain of the central pathways of intermediary metabolism, such as the citric acid cycle, and many metabolites of other pathways have dual purposes—they serve in both catabolism and anabolism. This dual nature is reflected in the designation of such pathways as amphibolic rather than solely catabolic or anabolic. In any event, in contrast to catabolism—which converges to the common intermediate, acetyl-CoA—the pathways of anabolism diverge from a small group of simple metabolic intermediates to yield a spectacular variety of cellular constituents. 

ABSTRACT This article concerns various foundational aspects of the periodic system of the elements. These issues include the dual nature of the concept of an "element" to include element as a "basic substance" and as a "simple substance." We will discuss the question of whether there is an optimal form of the periodic table, including whether the left-step table fulfils this role. We will also discuss the derivation or explanation of the [n + , n] or Madelung rule for electron-shell filling and whether indeed it is important to attempt to derive this rule from first principles. In particular, we examine the views of two chemists, Henry Bent and Eugen Schwarz, who have independently addressed many of these issues. 2008 Wiley Periodicals, Inc. Int J Quantum Chem 109 959-971, 2009... 

This chapter explores solutions. Its main emphasis is on aqueous solutions, because water is the most important solvent for life. We first describe the nature of solutions. Then we examine the molecular features that determine whether one substance dissolves in another. We introduce some characteristic properties of solutions, including effects on phase behavior. The chapter concludes by looking more closely at dual-nature molecules such as those present in shampoos. 

Several factors contribute to the dual nature of silicone defoamers. For example, soluble silicones can concentrate at the air-oil interface to stabilize bubbles, while dispersed drops of silicone can accelerate the coalescence process by rapidly spreading at the gas-liquid interface of a bubble, causing film thinning by surface transport [1163]. 

In zinc chloride, zinc is present as the positive cation, Zn2+, whereas in sodium zincate, zinc is present as part of the negative zincate anion, (Zn02)2-. In the present context, reference must be drawn to water. It can accept a proton and can act as a base similarly, it can part with a proton and can act as an acid. Thus, it has an amphoteric (dual) nature. Water can function as a base in the presence of acids stronger than itself and as an acid in the presence of bases stronger than itself. As an example in the former category reference may be drawn to the reaction,... 

Thaller, L.H., and G. Thodos, "The Dual Nature of a Catalytic-Reaction The Dehydrogenation of sec-Buty Alcohol to Methyl Ethyl Ketone at Elevated Pressures", AIChE Journal, 6(3), 369-373, 1960. 

That light has a dual nature and behaves either like a wave or like a stream of particle-like photons is a fact we must accept, although it is nonintuitive. But remember, we have no direct experience of the behavior of very small particles such as electrons. Which model we use depends on the observations we are making. The wave model is appropriate when we are considering diffraction and interference experiments, but the particle (photon) model is essential when we are considering the interaction of light with individual atoms or molecules. 

In 1923 de Broglie made the bold suggestion that matter, like light, has a dual nature in that it sometimes behaves like particles and sometimes like waves. He suggested that material (i.e., non-zero-rest mass) particles with a momentum p = mv should have wave properties and a corresponding wavelength given by... 

The ground water from well 6 (site 1) yielded both the most depleted S13C and most enriched 834S. Isotopic compositions of this dual nature are consistent with methanogenesis and bacterial sulfate reduction, arising form interaction with organic-rich (bog) soils from below. 

Methods for the A-acylation of similar heterocycles, such as simple thiazolidinethiones, have been reported since 1977, namely acyl chlorides in miscellaneous conditions,586 or carboxylic acids under DCC-activation.60,61 However the easiest and most effective method involves acyl chlorides or carboxylic anhydrides in the presence of an amine.47 Applying that procedure on carbohydrate scaffolds Rollin and co-workers62 reported the synthesis of diverse /V-acylated OZTs. The reactions were performed with good yields and the /V-selective acylation was ascertained by NMR— namely the thiocarbonyl 13C chemical shift (Scheme 41). Thanks to the dual nature of the carbanion drifting in the reaction,596 60 no competitive formation of the thioester, as mentioned by Plusquellec el al. in the case of benzothiazole, was observed. 

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