Alternative methods reporting

An alternative method for measuring air permeabiUty is based on measuring differential pressure when a constant rate of air flow passes through the fabric. In this case, air resistance is reported in typical units of kPa-s/m. 

Cl Vat Blue 4 is prepared from 2-arniaoaiitliraquiQoiie (66) by potash fusion in the presence of an oxidising agent such as sodium nitrite or air. An alternative method by dimerization of 1-aminoanthraquinone (17) by using such solvents as dimethyl sulfoxide or tetramethylurea has been reported, and improved methods for this reaction have been cited (135—138). These methods are considered to be advantageous in terms of the yield as well as the availability of starting compounds. 

An alternate method for predicting the flood point of sieve and valve plates has been reported by Kister and Haas [Chem. Eng. Progi , 86(9), 63 (1990)] and is said to reproduce a large data base of measured flood points to within 30 percent. It applies to entrainment flooding only (values of Flc less than about 0.5). The general predictive equation is... 

Two- and three-component Hantzsch reactions using C-glycosylated reagents have been reported as an alternate method for conducting asymmetric syntheses of 1,4-dihydropyridines." ° Reaction of 109, 110 and 97 generate 111 with Ri = sugar. Alternatively, 112 and 113 produce 111 with Ri = sugar. While the yields were acceptable (60-90%), the diastereomeric ratio varied from 30-60%. 

When asymmetric epoxidation of a diene is not feasible, an indirect route based on asymmetric dihydroxylation can be employed. The alkene is converted into the corresponding syn-diol with high enantioselectivity, and the diol is subsequently transformed into the corresponding trans-epoxide in a high-yielding one-pot procedure (Scheme 9.5) [20]. No cpirricrizalion occurs, and the procedure has successfully been applied to natural product syntheses when direct epoxidation strategies have failed [21]. Alternative methods for conversion of vicinal diols into epoxides have also been reported [22, 23]. 

Our group has recently developed an alternative method for alkyl-(hetero)aryl- as well as aryl-heteroaryl cross coupling reactions catalyzed by iron salts.3 4 This methodology was inspired by early reports of Kochi et al.5>6 on iron-catalyzed cross coupling of vinyl halides and is distinguished by several notable advantages. 

Important results and a detailed insight into aqueous chemical deposition processes have been reported and discussed elsewhere for CdSe [248, 249] and ZnS [250, 251] target products. We should note also the work of Davies et al. [252] who described an alternative method for the chemical growth of metal sulfides and selenides on the basis of polysulfide or polyselenide solutions (containing hexa- and tetra-chalcogen anions) formed by the dissolution of sulfur or selenium in hydrazine monohydrate. ... 

Fixed pathlength transmission flow-cells for aqueous solution analysis are easily clogged. Attenuated total reflectance (ATR) provides an alternative method for aqueous solution analysis that avoids this problem. Sabo et al. [493] have reported the first application of an ATR flow-cell for both NPLC and RPLC-FUR. In micro-ATR-IR spectroscopy coupled to HPLC, the trapped effluent of the HPLC separation is added dropwise to the ATR crystal, where the chromatographic solvent is evaporated and the sample is enriched relative to the solution [494], Detection limits are not optimal. The ATR flow-cell is clearly inferior to other interfaces. 

Whereas the use of conventional fast atom bombardment (FAB) in the analysis of polymer/additive extracts has been reported (see Section 6.2.4), the need for a glycerol (or other polar) matrix might render FAB-MS analysis of a dissolved polymer/additive system rather unattractive (high chemical background, high level of matrix-, solvent- and polymer-related ions, complicated spectra). Yet, in selected cases the method has proved quite successful. Lay and Miller [53] have developed an alternative method to the use of sample extraction, cleanup, followed by GC in the quantitative analysis of PVC/DEHP with plasticiser levels as typically found in consumer products (ca. 30 %). The method relied on addition of the internal standard didecylphthalate (DDP) to a THF solution of the PVC sample with FAB-MS quantitation based on the relative signal levels of the [MH]+ ions of DEHP and DDP obtained from full-scan spectra, and on the use of a calibration curve (intensity ratio m/z 391/447 vs. mg DEHP/mg DDP). No FAB-matrix was added. No ions associated with the bulk of the PVC polymer were observed. It was... 

An alternative method of preparing the saturated cyclic amines via cyclopolymerization of diallylamine or diallylammonium chloride was unsuccessful. Common free radical initiators such as 2,2 -azobisisobutyronitrile, ammonium persulfate, benzoyl peroxide were found to be ineffective. Several procedures reported in the literature were followed, and unfortunately all of them have resulted only a small amount of low molecular weight oligomers. Further research for polymerization conditions and types of initiation is still required. 

A special tearing procedure known as diakoptics (K10) was investigated by Brameller et al. (BIO) and by Gay and Middleton (Gl). According to Brameller et al. (BIO), this procedure lends itself very readily to the exercise of engineering judgment. However, computational performance of this method reported by Gay and co-workers (Gl, G2) has not been too impressive. The more recent work of Gay and Preece (G2) indicates that the nodal method of diakoptics is outperformed by an alternative method based on formulation D for problems up to 100 edges and 50 cycles. 

Within the project we also evaluated alternative methods as tools to obtain information on the toxicological and physicochemical profile of the pollutants. In this paragraph, an example of the application of QSARs models is reported a comparison is done between predicted values from different models or between QSARs evaluation and experimental values from internationally recognized databases. 

Isonitrile cyclization provides a useful alternative method of the Knorr type cyclization for pyrrole synthesis. In 1972, Leusen and coworkers reported pyrrole synthesis based on the reaction of tosylmethyl isocyanide (TosMIC) with electron-deficient alkenes (Eq. 10.12).15... 

During the last decades, a large body of structural information has been derived from gas-electron diffraction studies. The corresponding results are nearly exclusively reported in the literature in terms of r distances, or the equivalent thermal average intemuclear distances, which are denoted r. The r distances are defined by the relation, r = r — If. Alternative methods for interpreting gas-electron diffraction data are possible, for example, in terms of -geometries5, but they are currently too complex to apply in routine stmctural analyses, because they require detailed information on the molecular potential energy surface which is not usually available. 

An alternative method of six-membered ring formation has been reported utilizing an SNAr mechanism (Equation 31) <2002J(P1)790>. Chlorine is set up to leave by the electron-withdrawing influence of a group 138. The... 

Rotane 83 was similarly prepared from the olefin 82, albeit by a newly modified Simmons-Smith reaction with silver replacing the copper in the above reaction scheme 28). An alternative method from 79 was also reported 28-30). Deductions have been made as to the strain energy of [3]rotane29K... 

Dye identification is of great interest in textile studies. The classical procedure requires a hydrolysis step and other extraction techniques, followed by identification of the individual compounds present after separation by a chromatographic technique, e.g. high-performance liquid chromatography [Novotna et al. 1999, Szostek et al. 2003]. However, ToF-SIMS can be an alternative method, avoiding the phase of extraction which is always a time consuming and delicate step because of the possible destruction of the molecular structure of the sample [Ferreira et al. 2002]. The development of ToF-SIMS for dye detection has been reported in different studies. 

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