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Hydrides activity

Hydrogen may also be determined by both electrochemical and diffusion meters. The electrochemical meter is a hydride-activated concentration cell that employs an electrolyte consisting of a CaH2-CaCl2 mixture. The diffusion meter is based on the equilibrium pressures attained on either side of a thin membrane, usually nickel. [Pg.337]

Figure 15-13. Hysteresis during formation and decomposition of hydrides activity aH vs. mole fraction. VH (schematic). Figure 15-13. Hysteresis during formation and decomposition of hydrides activity aH vs. mole fraction. VH (schematic).
Hydrogen forms three types of binary hydrides. Active metals give ionic hydrides, such as LiH and CaFF nonmetals give covalent hydrides, such as NH3, H2O, and HF and transition metals give metallic, or interstitial, hydrides, such as PdH,.. Interstitial hydrides are often nonstoichiometric compounds. [Pg.602]

Cholic acid and 3-phenylcarbamoyl cholic acid allyl esters were grafted to hydride-activated silica gel and the developed CSPs were used for the chiral resolution of derivatized amino acids, amines, alcohols, hydantoins, and 2,2 -... [Pg.325]

The precipitated brown / -TiCl3 undergoes, in certain spots of its surface, an alkylation reaction with the organoaluminium compound present in the reaction system, which results in the formation of active species with a Ti-C bond (or with a Ti-H bond in the case of a metal hydride activator (in these spots, scheme (8) shows the activation of a catalyst precursor such as TiCl3 with AIR3 as the catalyst activator ... [Pg.57]

Homogeneous Catalysts without a Metal Alkyl (or Hydride) Activator... [Pg.81]

Table 5.1 Polymerisation of 1,3-butadiene with aluminium alkyl or hydride-activated Ziegler-Natta catalysts... Table 5.1 Polymerisation of 1,3-butadiene with aluminium alkyl or hydride-activated Ziegler-Natta catalysts...
Catalysts Based on Transition Metal Salts without an Organometallic or Metal Hydride Activator... [Pg.295]

Metal hydrocarbyl or hydride-activated catalysts are in principle susceptible to deactivation by reactions with traces of moisture and other protic compounds however, the activity of soluble catalysts can be enhanced in some instances by the addition of a protic compound as the third component [107], It is also worthy noting that soluble catalyst precursors can give, after activation with organometallic compounds, soluble or finely divided heterogeneous catalysts. [Pg.351]

Interesting features in the polymerisation of acetylenic monomers are displayed by rhodium-based catalysts they may be applied in metal akyl or hydride-activated systems, e.g. RhCl3-LiBH4 [49] and [(Cod)Rh]1 [[BPh4]... [Pg.382]

It has been demonstrated recently that conventional metathesis catalysts, used as a combination of aryloxytungsten-based precursor and tetramethyltin, tetrabutyltin or tributyltin hydride activator, are capable of promoting acyclic diene metathesis polycondensation [27] ... [Pg.403]

One might, of course, argue that this statement is only valid for the chemical system while everything might be quite different in enzymes. On the other hand, what an apoprotein does to a cofactor is not magic, but chemistry. Apparently, nature overcomes the 2e"-only-limitation of its unique hydride activator, nicotinamide, by a mandatory transformer,... [Pg.327]

Handling, Storage, and Precautions air sensitive, reacting instantaneously with protic solvents to liberate hydrogen must be handled under an inert atmosphere (N2 or Ar) can be stored at 0 °C under inert atmosphere for several months without loss of hydride activity. ... [Pg.225]

A coordinatively unsaturated osmium hydride activates the H-Si bond in HSiEt3 ... [Pg.451]


See other pages where Hydrides activity is mentioned: [Pg.300]    [Pg.311]    [Pg.403]    [Pg.43]    [Pg.285]    [Pg.292]    [Pg.112]    [Pg.113]    [Pg.114]    [Pg.370]    [Pg.370]    [Pg.454]    [Pg.420]    [Pg.106]    [Pg.195]    [Pg.53]    [Pg.116]    [Pg.282]    [Pg.283]    [Pg.287]    [Pg.341]    [Pg.350]    [Pg.351]    [Pg.382]    [Pg.577]    [Pg.420]    [Pg.120]    [Pg.403]   
See also in sourсe #XX -- [ Pg.503 ]




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Activation energy hydride transfer reactions

Activation of hydrides

Active metals metal hydrides

Activity alkali metal hydride

Aluminium Alkyl or Hydride-activated

Diisobutylaluminum hydride activation

Hydride activation

Hydride activation

Hydride transfer activation

Hydride transfer coenzyme activation

Hydrides activated

Hydrides and Dihydrogen Activation

Hydrides, Hydrogen Bonding and Dihydrogen Activation

Hydrogen activation hydride oxidation

Metal hydrides activity

Optically active compounds reduction with chiral hydrides

Some Recent Developments in Hydrogenation Activation of Hydrides by Transition Metal Derivatives

Spectroscopic Probes of Hydride Transfer Activation by Enzymes

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