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Super mechanism

Carbon nanotubes (CNTs) are one-dimensional nanomaterials with cylindrical structures consisting of sp carbon bonds [9]. It is believed that CNTs are ideal nanofillers due to its super mechanical [10], thermal [11, 12], and electrical properties. Two main commercial players for PNCs are multiwalled carbon nanotubes (MWCNTs) with a diameter range from 4 to 30 nm and single-walled carbon nanotubes (SWCNTs) with a diameter range from 0.4 to 2-3 nm. This section will follow the in-situ approaches to incorporate CNTs into PU elastomer, solvent-based and waterborne PU. [Pg.170]

Clary D C, Gilbert R G, Bernshtein V and Oref I 1995 Mechanisms for super collisions Faraday Discuss. Chem. Soc. 102 423-33... [Pg.1087]

Equip a 3 litre three-necked flask with a thermometer, a mercury-sealed mechanical stirrer and a double-surface reflux condenser. It is important that all the apparatus be thoroughly dry. Place 212 g. of trimethylene dibromide (Section 111,35) and 160 g. of ethyl malonate (Section 111,153) (dried over anhydrous calcium sulphate) in the flask. By means of a separatory funnel, supported in a retort ring and fitted into the top of the condenser with a grooved cork, add with stirring a solution of 46 g. of sodium in 800 ml. of super dry ethyl alcohol (Section 11,47,5) (I) at such a rate that the temperature of the reaction mixture is maintained at 60-65° (50-60 minutes). When the addition is complete, allow the mixture to stand until the temperature falls to 50-55°, and then heat on a water bath until a few drops of the liquid when added to water are no longer alkaline to phenolphthalein (about 2 hours). Add sufficient water to dissolve the precipitate of sodium bromide, and remove the alcohol by distillation from a water bath. Arrange the flask for steam distillation (Fig. this merely involves... [Pg.858]

Ethyl phenylethylmalonate. In a dry 500 ml. round-bottomed flask, fitted with a reflux condenser and guard tube, prepare a solution of sodium ethoxide from 7 0 g. of clean sodium and 150 ml. of super dry ethyl alcohol in the usual manner add 1 5 ml. of pure ethyl acetate (dried over anhydrous calcium sulphate) to the solution at 60° and maintain this temperature for 30 minutes. Meanwhile equip a 1 litre threenecked flask with a dropping funnel, a mercury-sealed mechanical stirrer and a double surface reflux condenser the apparatus must be perfectly dry and guard tubes should be inserted in the funnel and condenser respectively. Place a mixture of 74 g. of ethyl phenylmalonate and 60 g. of ethyl iodide in the flask. Heat the apparatus in a bath at 80° and add the sodium ethoxide solution, with stirring, at such a rate that a drop of the reaction mixture when mixed with a drop of phenolphthalein indieator is never more than faintly pink. The addition occupies 2-2 -5 hoius continue the stirring for a fiuther 1 hour at 80°. Allow the flask to cool, equip it for distillation under reduced pressure (water pump) and distil off the alcohol. Add 100 ml. of water to the residue in the flask and extract the ester with three 100 ml. portions of benzene. Dry the combined extracts with anhydrous magnesium sulphate, distil off the benzene at atmospheric pressure and the residue under diminished pressure. C ollect the ethyl phenylethylmalonate at 159-160°/8 mm. The yield is 72 g. [Pg.1004]

The mesopores make some contribution to the adsorptive capacity, but thek main role is as conduits to provide access to the smaller micropores. Diffusion ia the mesopores may occur by several different mechanisms, as discussed below. The macropores make very Htde contribution to the adsorptive capacity, but they commonly provide a major contribution to the kinetics. Thek role is thus analogous to that of a super highway, aHowkig the adsorbate molecules to diffuse far kito a particle with a minimum of diffusional resistance. [Pg.254]

Low Expansion Alloys. Binary Fe—Ni alloys as well as several alloys of the type Fe—Ni—X, where X = Cr or Co, are utilized for their low thermal expansion coefficients over a limited temperature range. Other elements also may be added to provide altered mechanical or physical properties. Common trade names include Invar (64%Fe—36%Ni), F.linvar (52%Fe—36%Ni—12%Cr) and super Invar (63%Fe—32%Ni—5%Co). These alloys, which have many commercial appHcations, are typically used at low (25—500°C) temperatures. Exceptions are automotive pistons and components of gas turbines. These alloys are useful to about 650°C while retaining low coefficients of thermal expansion. Alloys 903, 907, and 909, based on 42%Fe—38%Ni—13%Co and having varying amounts of niobium, titanium, and aluminum, are examples of such alloys (2). [Pg.122]

Nucleation is initiated by secondary mechanisms involving the seed crystals or low super-saturation and high surface area of seed crystals eliminate or minimize nucleation seed crystals grow... [Pg.354]

Acrylic adhesives cure by a free radical chain growth mechanism. In contrast, epoxy and urethane adhesives cure by a step growth mechanism. This has a major impact on the cure kinetics, as well as the composition of the adhesive during cure ([9], pp. 6-9). Cyanoacrylate adhesives (such as Super Glue ) also cure by chain growth, but the mechanism is ionic with initiation by surface moisture. [Pg.825]

But regardless of these disagreements as to what exactly the term ab initio means I want to presume to define a new term that I shall call super ab initio . In the rest of this article I would like to suggest the kind of explanations which might be possible when we arrive at the point of being able to perform super-ab initio calculations in which no feature whatsoever is introduced by recourse to experimental data. This will be done especially regarding attempts to explain, or reduce, the periodic system of the elements by using quantum mechanics. [Pg.96]

Resistance to DDT has been developed in many insect species. Although there are some cases of metabolic resistance (e.g., strains high in DDT dehydrochlorinase activity), particular interest has been focused on kdr and super kdr mechanisms based upon aberrant forms of the sodium channel—the principal target for DDT. There are many examples of insects developing resistance to dieldrin. The best-known mechanism is the production of mutant forms of the target site (GABA receptor), which are insensitive to the insecticide. [Pg.132]

Indeed, the resistance problem has sometimes been severe enough to threaten a loss of control over the pest. A study of a number of resistant strains from the field has revealed two major types of resistance mechanism. Some individuals possess aberrant forms of the target site, the Na" channel. At least two forms are known that confer either kdr (<100-fold) or super kdr (>100-fold) resistance, which is the consequence of the presence of insensitive forms of the Na+ channel protein (McCaffery 1998, and Chapter 4, Section 4.4 of this book). [Pg.238]

The reaction mechanisms associated with pathways (A) and (B) may share In common such adsorbed Intermediates as peroxide, super-oxide and their corresponding protonated forms. The distinction between pathways (A) and (B) can become therefore a matter of whether an Intermediate such as peroxide (H02 ) desorbs In significant quantities or not for example,... [Pg.536]


See other pages where Super mechanism is mentioned: [Pg.206]    [Pg.212]    [Pg.208]    [Pg.206]    [Pg.212]    [Pg.208]    [Pg.2798]    [Pg.816]    [Pg.913]    [Pg.1002]    [Pg.1005]    [Pg.163]    [Pg.309]    [Pg.369]    [Pg.369]    [Pg.62]    [Pg.192]    [Pg.361]    [Pg.695]    [Pg.47]    [Pg.128]    [Pg.1206]    [Pg.175]    [Pg.716]    [Pg.4]    [Pg.165]    [Pg.166]    [Pg.187]    [Pg.246]    [Pg.148]    [Pg.526]    [Pg.531]    [Pg.115]    [Pg.116]    [Pg.212]    [Pg.89]    [Pg.816]    [Pg.913]    [Pg.1229]   
See also in sourсe #XX -- [ Pg.305 ]




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