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Open stable

LR White resin Store at 4°C let the bottle come to room temperature before opening stable for 1 yr. [Pg.321]

WAVE Optimized Buffer A (Transgenomic, Inc., Omaha, NE, cat. no. 553401) or equivalent, 100 mM TEAA. Store at room temperature stable up to 1 mo opened, stable up to 1 yr unopened. [Pg.78]

Fig. 5 S-SPl(left) and protonated open stable TCCOHa" (right) calculated at CAM-B3LYP/6-311+G(d,p). Note that the SP-O-protonated form is not stable... Fig. 5 S-SPl(left) and protonated open stable TCCOHa" (right) calculated at CAM-B3LYP/6-311+G(d,p). Note that the SP-O-protonated form is not stable...
Thus they have been replaced with elements with a martensite structure mixture fully transformed by the zero processing and mounted in openings with insens of austenite steel (Fig.3). Thus prepared elements for caUbration. will be stable with time and will not cause any indication changes during exploitation. [Pg.22]

Most chemically reacting systems tliat we encounter are not tliennodynamically controlled since reactions are often carried out under non-equilibrium conditions where flows of matter or energy prevent tire system from relaxing to equilibrium. Almost all biochemical reactions in living systems are of tliis type as are industrial processes carried out in open chemical reactors. In addition, tire transient dynamics of closed systems may occur on long time scales and resemble tire sustained behaviour of systems in non-equilibrium conditions. A reacting system may behave in unusual ways tliere may be more tlian one stable steady state, tire system may oscillate, sometimes witli a complicated pattern of oscillations, or even show chaotic variations of chemical concentrations. [Pg.3054]

For solids which melt above 100° and are stable at this temperature, drying may be carried out in a steam oven. The crystals from the Buchner funnel should then be placed on a clock glass or in an open dish. The substance may sometimes be dried in the Buchner funnel itself by utilising the device illustrated in Fig. 77, <33, 1. An ordinary Pyrex funnel is inverted over the Buchner funnel and the neck of the funnel heated by means of a broad flame (alternatively, the funnel may be heated by a closely-fltting electric heating mantle) if gentle suction is applied to the Alter flask, hot (or warm) air will pass over the crystalline solid. [Pg.132]

The key initiation step in cationic polymerization of alkenes is the formation of a carbocationic intermediate, which can then interact with excess monomer to start propagation. We studied in some detail the initiation of cationic polymerization under superacidic, stable ion conditions. Carbocations also play a key role, as I found not only in the acid-catalyzed polymerization of alkenes but also in the polycondensation of arenes as well as in the ring opening polymerization of cyclic ethers, sulfides, and nitrogen compounds. Superacidic oxidative condensation of alkanes can even be achieved, including that of methane, as can the co-condensation of alkanes and alkenes. [Pg.102]

Alkene synthesis via alcohol dehydration is complicated by carbocation rearrangements A less stable carbocation can rearrange to a more sta ble one by an alkyl group migration or by a hydride shift opening the possibility for alkene formation from two different carbocations... [Pg.222]

This suggests that as water attacks the bromonium ion positive charge develops on the carbon from which the bromine departs The transition state has some of the character of a carbocation We know that more substituted carbocations are more stable than less substituted ones therefore when the bromonium ion ring opens it does so by breaking the bond between bromine and the more substituted carbon... [Pg.260]

Compounds that contain both carbonyl and alcohol functional groups are often more stable as cyclic hemiacetals or cyclic acetals than as open chain compounds Examples of several of these are shown Deduce the structure of the open chain form of each... [Pg.748]

The sp hybridized carbon of an acyl chloride is less sterically hindered than the sp hybridized carbon of an alkyl chloride making an acyl chloride more open toward nude ophilic attack Also unlike the 8 2 transition state or a carbocation intermediate m an Stvfl reaction the tetrahedral intermediate m nucleophilic acyl substitution has a stable arrangement of bonds and can be formed via a lower energy transition state... [Pg.841]

Nitration and halogenation of furfural occurs under carehiUy controlled conditions with introduction of the substituent at the open 5-position (24,25). Nitration of furfural is usually carried out in the presence of acetic anhydride, resulting in the stable compound, 5-nitrofurfuryhdene diacetate (26,27). The free aldehyde is isolated by hydrolysis and must be used immediately in a reaction because it is not very stable. [Pg.77]

The Vanderbilt process involves the mechanical frothing of air into a plastisol containing proprietary surfactants by means of an Oakes foamer or a Hobart-type batch whip. The resulting stable froth is spread or molded in its final form, then gelled and fused under controlled heat. The fused product is open-ceUed with fine cell size and density as low as 160 kg/m (10 lbs/fT). [Pg.420]

Because of the rapid ring opening by the nucleophile, ayiridinium salts cannot usually be isolated. However, in a few cases it is possible to isolate such compounds (54), eg, at low temperatures, when the ayiridinium salts ate sparingly soluble or where there is steric hindrance to substitution. Stable ethyleneiminium salts can be prepared by reaction of ethyleneimine with acids not containing nucleophilic anions, for example HBF (55). [Pg.3]

Although reasonably stable at room temperature under neutral conditions, tri- and tetrametaphosphate ions readily hydrolyze in strongly acidic or basic solution via polyphosphate intermediates. The hydrolysis is first-order under constant pH. Small cycHc phosphates, in particular trimetaphosphate, undergo hydrolysis via nucleophilic attack by hydroxide ion to yield tripolyphosphate. The ring strain also makes these stmctures susceptible to nucleophilic ring opening by other nucleophiles. [Pg.339]

Sediment Volume. If the dispersion is unstable, the sediment bed will be quite deep and sedimenting particles will stick together where they first strike the sediment bed, thus forming an open stmcture with considerable occluded Hquid. If the dispersion is stable to reagglomeration, the particles will move freely past one another to avoid contact as long as possible. The result is a thin sediment bed with maximum soHds packing and minimum occluded hquid (12). Since dispersed particles setde more slowly than docs, centrifugation maybe needed to force sedimentation of small particles within a reasonable analysis time. [Pg.549]

Primary cycloaUphatic amines react with phosgene to form isocyanates. Reaction of isocyanates with primary and secondary amines forms ureas. Dehydration of ureas or dehydrosulfuri2ation of thioureas results in carhodiimides. The nucleophilicity that deterrnines rapid amine reactivity with acid chlorides and isocyanates also promotes epoxide ring opening to form hydroxyalkyl- and dihydroxyalkylaniines. Michael addition to acrylonitrile yields stable cyanoethylcycloalkylarnines. [Pg.208]


See other pages where Open stable is mentioned: [Pg.58]    [Pg.599]    [Pg.58]    [Pg.599]    [Pg.1096]    [Pg.2608]    [Pg.3055]    [Pg.345]    [Pg.54]    [Pg.423]    [Pg.1046]    [Pg.200]    [Pg.57]    [Pg.211]    [Pg.319]    [Pg.387]    [Pg.293]    [Pg.311]    [Pg.17]    [Pg.271]    [Pg.24]    [Pg.10]    [Pg.200]    [Pg.22]    [Pg.13]    [Pg.145]    [Pg.389]    [Pg.110]    [Pg.551]    [Pg.563]    [Pg.460]   
See also in sourсe #XX -- [ Pg.19 ]




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