Multi-step methods

However, as regards the conventional method, a linearity exists only in the case when the fan was off, and the track densities T in the turbulent atmosphere were higher than those in the still atmosphere. The calibration coefficients K and K were calculated with a multi-step method of linear regression analysis (Skinner and Nyberg,... 

Noteworthy is a recent multi-step method for the production of molecular [ F]F2 of considerable higher specific radioactivity (100-925 Ci/mmol or 3.7-34 TBq/ mmol) starting from aqueous [" Fjfluoride produced with the 0(p,n) F reaction [38], The dried and activated [ F]fluoride is reacted with methyl iodide to yield methyl [ F]fluoiide (CHsf FjF) which is isolated by gas chromatography. The latter is then subjected to an electrical discharge (20-30 kV, 280 pA, 10 s) in the presence of small amounts of carrier fluorine (150 nmol) resulting in about 30% conversion of the original [ F]fluoride into molecular [ F]F2. 

The following multi-step method may be used for calculating the required orifice area for SRVs on vessels containing liquids that are potentially exposed to fire. (Reference API Recommended Practice 521, Fourth Edition.)... 

These organozincs, 1 (n = 2, 3, and 4), react with diverse acid chlorides to yield y. 5. and e-keto esters, respectively, in good yields. Two typical examples are shown in eq 3 and 4. The product of eq 3, ethyl 5-oxo-6-heptenoate, may be prepared by laborious, multi-step methods. The title compound, ethyl 5-oxo-6-methyl-6-heptenoate, is a new compound. 

In contrast, if all proteins have to be extracted, e.g. for the study of the grape biology, it is necessary to adopt a multi-step method in order to minimize protein losses occurring with rupture of the cells and proteins interaction with phenolic compounds. 

Liniger, W., Odeh, F. A-Stable Accurate Averaging Multi-step Methods for Stiff Differential Equations. IBM J. Res. Develop. 16, 335 (1972). 

Bohlmann and his co-workers have described the synthesis of polyacetylenes from l-bromo-2-phenylacetylene and butadiyne in the presence of copper(i) chloride503 and by a multi-step method from bromopropiolic acid.504... 

One can produce 6-ohloro-2(IH)-quinoxalinone, via the N-oxide by, a multi-step method by condensing 4-chloro-2-nitroaniline, (111), and diketene,(IV), to produce 4-ohloro-2 -nitroacetoacet-anilide, (V). Patents and literature - reveal the reaction is carried out in the presence of a nucleophillic amine (Figure 3). 

For the integration of the differential equations a number of numerical standard methods exist, such as Runge-Kutta or multi step methods [31]. In the... 

In this direct method number of hapten was much greater than Rgl-BSA conjugate synthesized by multi-step method[8] though the binding site is different(Table 1). In this direct method ginsenoside Rbl showed much greater number of hapten than solamargine(Table 1). Hapten density may affect antibody formation. 

Based on the number of points tn used in the formula one-step or multi-step methods. 

Although the integration step changes are rather difficult to perform in multi-step methods, they are quite easy with the midtivalue methods. In fact, you only need to scale the elements of z to adapt it to the new step ... 

Therefore, in order to obtain 1,5-PeD selectively, the multi-step method has been reported (4) [25]. This system is composed of three separated steps including dehydration of THFA to dihydropyran, hydration of dihydropyran to 5-hydroxyvaleraldehyde, and hydrogenation of 5-hydroxyvaleraldehyde to 1,5-PeD. The system requires the isolation and purification of the intermediates and the overall yield was 70%. Hydrogenolysis of THFA to 1,5-PeD also seems to be simple judging from the reaction formula (3), just like the case of the glycerol hydrogenolysis however, the selective synthesis of 1,5-PeD from THFA had not been realized. 

There are of course more elaborate ways to study the electrochemistry - one way is to have a system in total balance without removing electrons out of the system. Creating a thermo-dynamic Born-Haber cycle (TD cycle. Fig. 9.2) for the system of interest is the most common example of such an approach [10, 11, 28, 29]. The main advantage is the reduced need for adjustments for the precise chemistry involved experimentally, as all components treated in the computational model do more or less have exactly the same physical surrounding as in the experiment compared with. Indeed, the TD cycle multi-step method is often quite... 

Multi-step Method Independent Fe or Co precursors, N and C sources Pyrolyzed at -1000 °C in argon CNCo Onset potential 790-800 mv (vs. RHE) [41]... 

Ynamide preparation via oxidative coupling of amides and alkynes represents an efihcient alternative to known multi-step methods, such as alkyne halogenation or the synthesis of alkynyliodonium salts followed by C-N formation. The only shortcoming of this system is that 5 equiv of the amide are necessary to achieve satisfactory yields. 

What characterizes multi-step methods, and why are they often nsed ... 

Abstract Amines are important organic compounds with a wide range of application in the synthesis of fine chemicals. Although many multi-step methods have been well developed for their synthesis, one step methods for the synthesis of amine, especially, aliphatic primary amine via direct C-H or C-C bond nitrogention are less developed and full of challenge. 

MirabaUes-Martinez, 1., Martm-MoUna, A., Galisteo-Gonzalez, F., and Forcada. J. 2001. Synthesis of amino functionalized latex particles by a multi-step method. J. Polym. Sci. Part A Polym. Chem. 39 2929-36. 

The above section considered anionic cyclization of enediynes and related molecules in a one-pot process, in contrast to the known classical multi-step methods [260, 327-329]. One-step anionic cycloaromatization of enediynes is also an effective method for the synthesis of biarenes [328]. Depending on the reaction conditions and substrate structure, the process can go by two routes. For example, when a methoxide ion attacks the nitrile function of enediyne 3.691, there follows a cascade of cycloaromatization reactions by an anionic pathway, affording phenanthridinones 3.692 in 50% yield after chromatographic purification. On the other hand, reaction of enediyne 3.691 with sodium methoxide in methanol in the presence of two equivalents of tetra-butylammonium iodide at reflux leads to biaryl derivative 3.693 in 56-64% yield. Diynes 3.691 were synthesized in 40-98% yield by the Pd-catalyzed coupling reaction of 2-ethynylbenzonitrile 3.689 with 2-alkynyliodbenzenes 3.690 (Scheme 3.72) [327]. A similar procedure was applied to the cycloaromatization of a series of (Z)-l-aryl-3-decene-l,5-diynes 3.694 to produce biphenyls 3.695 in yields from 14% to 34% (Scheme 3.73) [327]. 

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