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Transition early

Rostgaard, Tine. 2004. Family Support Policy in Central and Eastern Europe A Decade and a Half of Transition. Early Childhood and Family Policy Series 8. Budapest United Nations Educational, Scientific, and Cultural Organization, Education Sector. [Pg.552]

Micellar structure has been a subject of much discussion [104]. Early proposals for spherical [159] and lamellar [160] micelles may both have merit. A schematic of a spherical micelle and a unilamellar vesicle is shown in Fig. Xni-11. In addition to the most common spherical micelles, scattering and microscopy experiments have shown the existence of rodlike [161, 162], disklike [163], threadlike [132] and even quadmple-helix [164] structures. Lattice models (see Fig. XIII-12) by Leermakers and Scheutjens have confirmed and characterized the properties of spherical and membrane like micelles [165]. Similar analyses exist for micelles formed by diblock copolymers in a selective solvent [166]. Other shapes proposed include ellipsoidal [167] and a sphere-to-cylinder transition [168]. Fluorescence depolarization and NMR studies both point to a rather fluid micellar core consistent with the disorder implied by Fig. Xm-12. [Pg.481]

However, with the advent of lasers, the teclmique of laser-induced fluorescence (LIF) has probably become the single most popular means of detennining product-state distributions an early example is the work by Zare and co-workers on Ba + FLT (X= F, Cl, Br, I) reactions [25]. Here, a tunable laser excites an electronic transition of one of the products (the BaX product in this example), and the total fluorescence is detected as a... [Pg.873]

A consideration of the transition probabilities allows us to prove that microscopic reversibility holds, and that canonical ensemble averages are generated. This approach has greatly extended the range of simulations that can be perfonned. An early example was the preferential sampling of molecules near solutes [77], but more recently, as we shall see, polymer simulations have been greatly accelerated by tiiis method. [Pg.2259]

Arrington C A, Morse M D and Doverstal M 1995 Spectroscopy of mixed early-late transition metal diatomics ScNi, YPd, and ZrCo J. Chem. Rhys. 102 1895... [Pg.2403]

The early MBER spectra were of two types first, pure rotational (microwave) transitions and, secondly, radiofrequency transitions between different hyperfine levels the latter were observable only for Ar-HCl, because... [Pg.2448]

Mashima K, Nakayama Y and Nakamura A 1997 Recent trends in polymerization of a-olefins catalyzed by organometallic complexes of early transition metals Adv. Polym. Sc/. 133 1-54... [Pg.2538]

Most of the ions produced by either thermospray or plasmaspray (with or without the repeller electrode) tend to be very similar to those formed by straightforward chemical ionization with lots of protonated or cationated positive ions or negative ions lacking a hydrogen (see Chapter l).This is because, in the first part of the inlet, the ions continually collide with neutral molecules in the early part of their transit. During these collisions, the ions lose excess internal energy. [Pg.73]

The ubiquitous use of the word Tine to describe an experimentally observed transition goes back to the early days of observations of visible spectra with spectroscopes in which the lines observed in, say, the spectmm of a sodium flame are images, formed at various wavelengths, of the entrance slit. Although, nowadays, observations tend to be in the form of a plot of some measure of the intensity of the transition against wavelength, frequency or wavenumber, we still refer to peaks in such a spectmm as lines. [Pg.34]

Addition of HCN to unsaturated compounds is often the easiest and most economical method of making organonitnles. An early synthesis of acrylonitrile involved the addition of HCN to acetylene. The addition of HCN to aldehydes and ketones is readily accompHshed with simple base catalysis, as is the addition of HCN to activated olefins (Michael addition). However, the addition of HCN to unactivated olefins and the regioselective addition to dienes is best accompHshed with a transition-metal catalyst, as illustrated by DuPont s adiponitrile process (6—9). [Pg.217]

The porous electrodes in PEFCs are bonded to the surface of the ion-exchange membranes which are 0.12- to 0.25-mm thick by pressure and at a temperature usually between the glass-transition temperature and the thermal degradation temperature of the membrane. These conditions provide the necessary environment to produce an intimate contact between the electrocatalyst and the membrane surface. The early PEFCs contained Nafton membranes and about 4 mg/cm of Pt black in both the cathode and anode. Such electrode/membrane combinations, using the appropriate current coUectors and supporting stmcture in PEFCs and water electrolysis ceUs, are capable of operating at pressures up to 20.7 MPa (3000 psi), differential pressures up to 3.5 MPa (500 psi), and current densities of 2000 m A/cm. ... [Pg.578]

Transition-Metal Catalyzed Cyclizations. o-Halogenated anilines and anilides can serve as indole precursors in a group of reactions which are typically cataly2ed by transition metals. Several catalysts have been developed which convert o-haloanilines or anilides to indoles by reaction with acetylenes. An early procedure involved coupling to a copper acetyUde with o-iodoaniline. A more versatile procedure involves palladium catalysis of the reaction of an o-bromo- or o-trifluoromethylsulfonyloxyanihde with a triaLkylstaimylalkyne. The reaction is conducted in two stages, first with a Pd(0) and then a Pd(II) catalyst (29). [Pg.87]

High density polyethylene (HDPE) is defined by ASTM D1248-84 as a product of ethylene polymerisation with a density of 0.940 g/cm or higher. This range includes both homopolymers of ethylene and its copolymers with small amounts of a-olefins. The first commercial processes for HDPE manufacture were developed in the early 1950s and utilised a variety of transition-metal polymerisation catalysts based on molybdenum (1), chromium (2,3), and titanium (4). Commercial production of HDPE was started in 1956 in the United States by Phillips Petroleum Company and in Europe by Hoechst (5). HDPE is one of the largest volume commodity plastics produced in the world, with a worldwide capacity in 1994 of over 14 x 10 t/yr and a 32% share of the total polyethylene production. [Pg.379]


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See also in sourсe #XX -- [ Pg.36 ]

See also in sourсe #XX -- [ Pg.283 ]




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Amido complexes early-transition-metal

CO insertion into early transition metal alkyls

Coordination polymerization early transition metal-based

Copolymers early transition metal catalysts

Crystal Structures of Early Transition Metals

Degenerate Metathesis with Early Transition-Metal Catalysts

Degenerate early transition-metal catalysts

Early Studies of Noninterstitial Transition Metal Ternary Hydrides

Early Transition Metal (Zr, Hf) Catalyzed Dialkylzinc Additions

Early Transition Metal Initiators

Early Transition and Rare Earth Metal Complexes with N-Heterocyclic Carbenes

Early Transition-Metal Systems

Early transition detection

Early transition metal chemistry

Early transition metal complex

Early transition metal halide clusters

Early transition metals polymerizations

Early transition metals, alternate

Early transition metals, syntheses

Early transition states, methane

Early transition-metal catalysts

Early-late transition states

Early-transition elements

Electronic Configuration of Early Transition Metals

Epoxidation early transition metals

Epoxidations of Alkenes Catalyzed by Early Transition Metals

Heterogeneous early transition-metal catalyst

Homogeneous Epoxidation by Early Transition Metals (Lewis Acid Mechanism)

Homogeneous early transition-metal catalyst

Organometallic early transition metals

Oxophilic species, early transition metals

Oxygen early transition metal oxides

Pyridines early transition metal complexes, reaction

Qualifying Leads for Transition to Early Trials

Reactions early transition metals

Sulfoxide complexes via early transition metals

Tetrahydrofuran Complexes of Selected Early Transition Metals

The Early Transition Metals

Transition metal carbonyls, early

Transition metal carbonyls, early catalyst developments

Transition metal early

Transition metals early research applications

Transition state early

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