Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Methods complementary

An alternative to the synthesis of epoxides is the reaction of sulfur ylide with aldehydes and ketones.107 This is a carbon-carbon bond formation reaction and may offer a method complementary to the oxidative processes described thus far. The formation of sulfur ylide involves a chiral sulfide and a carbene or carbenoid, and the general reaction procedure for epoxidation of aldehydes may involve the application of a sulfide, an aldehyde, or a carbene precursor as well as a copper salt. This reaction may also be considered as a thiol acetal-mediated carbene addition to carbonyl groups in the aldehyde. [Pg.249]

The main objective of this review article is to demonstrate the analytical capability of SFM techniques in areas of research where SFM gives the most unique and valuable information not accessible by other methods. Complementary to other reviews [65-69], we will focus on recent developments in SFM instrumentation which are particularly useful for polymer systems (Sect. 2) on quantitative characterisation of material properties and structure manipulation on the nanometer scale (Sect. 3) and on visualisation and probing of single macromolecules (Sect. 4). The interested reader can find the theoretical background as well as instrumentation of SFM in text books [52-54,70-72]. [Pg.66]

In such a situation, the only clear cut strategy that leads to a definite answer concerning the valence state of the iron is not only to apply spectroscopic methods complementary to Mossbauer spectroscopy but also to investigate complexes with similar ligands but different electronic configurations. In order to clarify the electronic configuration of [(Me3cy-ac)FeN](PF6)2, X-ray absorption spectroscopy (XAS) has... [Pg.2836]

Analytical determinations based on DNA recognition events can be carried out with various transducers - e.g., see review on optical transducers,151 and they can be treated as biosensing methods complementary to immunochemical methods and those utilizing molecular and whole cell receptors. [Pg.53]

A method complementary to the palladium-catalyzed reaction has been reported. A cobalt-phosphine complex catalyzes a Heck-type reaction of alkyl halides with styrenes in the presence of Me3SiCH2MgCl [174]. Trimethylsilylmethylmag-nesium chloride was added to a mixture of styrene and bromocyclohexane in ether in the presence of a catalytic amount of CoCl2(dpph) at O C. Heating the reaction mixture under reflux (35°C) provided 163a in 91% yield (Scheme 3.158). [Pg.142]

The IR-spectroscopy yields detailed information on the surface covering of the material under test. Therefore, it constitutes a method complementary to those analytical techniques chiefly characterizing the bulk properties. [Pg.354]

It should be noted that, in many cases, the use of only a single thermal analysis technique may not provide sufficient information about a given system. As with many other analytical methods, complementary or supplementary information, as can be furnished by other thermal analysis techniques, may be required. For example, it is fairly common to complement all DTA or DSC data with thermogravimetry. If one or more gaseous products result, evolved gas analysis may prove useful in solving the problem at hand. Simultaneous thermal techniques are helpful in this respect in that several types of data are obtained from the same sample under identical pyrolysis conditions. [Pg.832]

Thus, a method complementary to silylation of hydroxy acids is available. [Pg.98]

In Equation 12 the ionic intermediate is unspecified as to structure since it is not possible to distinguish in this experiment between a cyclic or open adduct. This chemistry, however, is thought to be identical to conventional thermal ion chemistry and raises the prospect that thermal carbonium ion intermediates can be generated and studied in this way at high dilution and very low energy in the gas phase. This exciting result provides a welcome new method complementary to ion cyclotron resonance and ion beam techniques. [Pg.144]

Regarding the FACE method, complementary frontal analysis might be used to check the determined isotherms at the breakthrough concentration. [Pg.391]

The diffusion description, elaborated by Christiansen around 1935 (Christiansen 1936) and fully systematised in 1940 by Kramers (Kramers 1940), was an interesting and successful method complementary to transition state theory (TST). It received, however, little or no attention in chemistry circles for a long time (Zambelli 2010). [Pg.22]

Analogues of 2-deoxy-p-KDO and 2-deoxy-a-NeulVAc continue to attract attention. A range of compounds has been reported which involve modification of 2-deoxy-p-KDO at C-8, including the chain extended analogues of type (IS), " and the same group has also prepared the C-glycosidic analogues (19) by methods complementary to those used earlier by other... [Pg.176]

Simultaneous methods are those that permit determination of two or more physical parameters using a single sample at the same time. However, the determination of a parameter and its difference with a reference site is not considered as a simultaneous method. Complementary methods are those where the same sample is not used during simultaneous or consecutive measurements. Coupled simultaneous techniques cover the application of two or more techniques to the same sample when several instruments are connected through an interface. Discontinuous methods generally include the application of two or more simultaneous techniques on the same sample, where the sampling for the second technique is discontinuous. Oscillatory and jumps methods cover dynamic procedures where the controlling parameter is time-temperature modulated. [Pg.381]


See other pages where Methods complementary is mentioned: [Pg.496]    [Pg.17]    [Pg.416]    [Pg.317]    [Pg.21]    [Pg.454]    [Pg.12]    [Pg.796]    [Pg.315]    [Pg.165]    [Pg.676]    [Pg.2836]    [Pg.676]    [Pg.58]    [Pg.3]    [Pg.372]    [Pg.2835]    [Pg.11]    [Pg.362]    [Pg.291]    [Pg.676]    [Pg.117]    [Pg.4817]    [Pg.306]    [Pg.562]    [Pg.79]   
See also in sourсe #XX -- [ Pg.356 ]




SEARCH



Chemical monitoring complementary methods

Complementariness

Complementary

Complementary pest control methods

Surface waters complementary methods

Survey on complementary spectroscopic methods

© 2024 chempedia.info