Meissner method

Fig. 51. Lead azide precipitated by Meissner method [111]. Courtesy J. Meissner.

NG for military uses was manufd by the Biazzi method at plants located in Iseleten and Wimmis, and by the Schmid-Meissner method at Gamsen. Other plants which manufd Dynamites also made NG for non-military commercial uses... 

Major uncertainties have to be considered especially when an estimate from the Meissner method (Rechsteiner, 1990) is used instead of an experimental boiling point. Furthermore, these errors are propagated when, for example, calculated p values are used together with calculated data to estimate the Henry s law constant. 

Two techniques for measuring uniaxial extensional viscosity of polymer melts are shown in Figure 3.24. In the first technique (Ballman method) poiymer melt is either glued or clamped at both ends, and then one end is moved in such a manner as to generate either a uniform extension rate, e, or a constant tensile stress. In the Meissner method, both ends of the melt are pulled at a constant velocity either to achieve a uniform extension rate or to provide a constant stress. 

Various methods are available for estimation of the normal boiling point of organic compounds. Lyman et al. review and give calcula-tional procedures for the methods of Meissner, Miller, and Lydersen/ Forman-Thodos. A more recent method that has been determined to be more accurate is the method of Pailhes, which reqmres one experimental vapor pressure point and Lydersen group contributions for critical temperature and critical pressure (Table 2-385). 

NG. Batch-wise production of NG is described in Vol 6, G99-102, and continuous methods such as the Schmid t-Meissner and Biazzi processes are discussed in Vol 3, C501 — 505. The Swedish injector process and the Hercules tubular nitrator will be described below, but before doing this we will discuss certain aspects of glycerin nitration that are common to both batch and continuous methods, and then contrast the main features of the batch process vs the continuous process... 

The pKa value of the equilibrium was found to be equal to 10.2. Meissner and coworkers36 studied also the reaction of OH radicals with DMSO, however, the product of this reaction has no optical absorption in the range 270-800 nm and they measured only the rate of this reaction by a competition method and obtained k = 4.2 x 109m-1s-1. 

The submitters obtained LHS in THF from Callery Chemical Co. and determined its concentration to be 1.15M by titration according to the method of Ireland (Ireland, R. Meissner, R. J. Org. Chem. 1991, 56, 4566-4568). The checkers purchased LHS as a 1M solution in THF from Aldrich Chemical Co. 

At the same time, Meissner, Kucharski and others [56,57] developed the quadratic MR CCSD method in a spin-orbital form which does not exploit the BCH formula. The unknown cluster amplitudes are calculated from the so-called generalized Bloch equation [45-47,49,64,65] (or in our language the Bloch equation in the Rayleigh-Schrodinger form)... 

An EU COST project under action D23 Metachem Metalaboratories for Complex Computational Applications in Chemistry . Project number D23/0001/01 European Metalaboratory for multireference quantum chemical methods (01/02/200118/07/2005). Participants P. Carsky, J. Pittner (J. Heyrovsky Institute, Prague, Czech Republic), 1. Hubac (Comenius University, Slovakia), S. Wilson (Rutherford Appleton Laboratory, UK), W. Wenzel (Universitat Dortmund Germany), L. Meissner (Nicholas Copernicus University Poland), V. Staemmler (Ruhr Universitat Bochum Germany), C. Tsipis (Aristotle University of Thessaloniki, Greece), A. Mavridis (National and Kapodistrian University of Athens, Greece). 

Let us recall, finally, that ec CCSD approaches exploit the complementarity of the Cl and CC methods in their handling of the dynamic and nondynamic correlations. While we use the Cl as an external source of higher than pair clusters, Meissner et al. [10,72-74] exploit the CC method to correct the Cl results (thus designing the CC-based Davidson-type corrections). This aspect will also be addressed below. 

Kontinuierliche Verfahren. Continuous methods, such as those of Schmid, Meissner Biazzi, for the prepn and purification of expls and pro-pints, have been used extensively in Ger. 

Continuous methods using the same installations as for manuf of NG are used now in Europe. Two of these installations, Schmid-Meissner and Biazzi, are described in Vol 3 of Encyci, pp C502—C504. We also know that continuous method of Schmid-Meissner is installed in Argentina at the Naval Explosives Plant. The same plant employs Bofors Continuous Method for manuf of TNT. Accdg to Ref 24, nearly 100% conversion of Gc to NGc is achieved by mixed acid nitration in liquid sulfur dioxide... 

THE CONTINUOUS METHOD OF LEAD AZIDE MANUFACTURE (ACCORDING TO MEISSNER [110, 111])... 

The continuous method for the manufacture of lead styphnate (according to Meissner [58, 59])... 

The following methods of manufg Normal LSt are briefly described by Urbanski (Ref 21, pp 218-20) l) Method used at Wolfrats-hausen, Germany and 2) Continuous Method of J. Meissner. In both methods starting materials are MgO, TNR Pb nitrate. In the 1st part of manuf, a suspension of Mg reacts with TNR in w to form soluble Mg Styphnate, while in the 2nd part MgSt reacts... 

Herz succeeded in preparing RDX by direct nitration of hexamine, but the yields were low and the process was expensive and unattractive for large scale production. Hale, at Picatinny Arsenal in 1925, developed a process for manufacturing RDX which produced yields of 68%. However, no further substantial improvements were made in the manufacture of RDX until 1940 when Meissner developed a continuous method for the manufacture of RDX, and Ross and Schiessler from Canada developed a process which did not require the use of hexamine as a starting material. At the same time, Bachmann developed a manufacturing process for RDX (1.5) from hexamine which gave the greatest yield. 

Note This modern plant (1955) may be considered among the best in the Americas. It was constructed by Bofors AB(Sweden) and by other European firms. Manuf of TNT is continuous (by the method of Bofors) and so is the manuf of NG (method of Meissner). Stainless steel is used for all apparatus. 

The process invented by Schmid and improved and developed by Meissner [40] has since been adopted in many factories. A distinctive feature of the improved method consists in the extensive use of metering devices and rotameters. 

In other experiments, the opposite method of fractionation by dissolution was applied. In this way G. Meissner [107] prepared a soluble fraction with a nitrogen content of 10.28%, in quantity about 4% by extracting a specimen of nitrocellulose with 12.17% N using 50 50 ether-alcohol. The insoluble part was composed of nitrocellulose of 12.32% N. 

A low second law efficiency is not always realistically improvable. Thus Weber and Meissner (Thermodynamics for Chemical Engineers, John Wiley, New York, 1957) found a 6% efficiency for the separation of ethanol and water by distillation which is not substantially improvable by redesign of the distillation process. Perhaps this suggests that more efficient methods than distillation should be sought for the separation of volatile mixtures, but none has been found at competitive cost. 

To estimate the boiling point with Meissner s method [6]... 

After Schmid s accidental death in 1930, Meissner extented the application of continuous method to nitration of substances like benzene, toluene, etc, The,FirmaMeissner", Koln,... 

Continuous Schmid-Meissner process for NG DEGN manufg, as used in Germany during WWII Continuous method for manufg PETN) 23)R.Ashcroft et al, BIOS Final Report 833orPB Rept 63877 (1946), Item 2,... 

Review of literature on nitration, including continuous method .) 29)Kirk Othmer 6 (1951), 29-30 9(1952, 324-27(Continuous methods of Schmid, Schmid Meissner Biazzi) 30)Stettbacher, Polvoras (1952), 81-3 (Continuous method of Biazzi) 31)W. deC. Crater,... 

At the time of writing this article, there are only two instruments in the market in the U.S.A. - the Rheometrics Extensional Rheometer, the RFX, and the Rheometrics Elongation Melt Rheometer, based on Meissner s rotary clamp method. The RFX is based on the opposing jet method. 

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