Berthelot method

It is common to compare the output of different explosives as their TNT equivalent , this being the weight of TNT that would produce the same explosive effect in similar circumstances. In the Berthelot method, the TNT equivalent is taken as the ratio of the power index of the explosive divided by the power index of TNT. The result is usually expressed as a percentage. 

For serum measurement the sensor system is calibrated with urea dissolved in 0.0185 mol/1 Tris-HCl buffer, pH 7.0 ((3 = 8 mmol/l). In this manner, disturbances caused by individually different sample pH values and variations in the buffer capacity are kept within the noise limits of the measuring system. Comparison with the Berthelot method resulted in the following equation ... 

An amperometric urea sensor based on the pH dependence of the anodic oxidation of hydrazine [365] can be utilized in the Glukometer GKM 02 for hemodialysis monitoring. For urea concentration in dialyzate the following correlation with the Berthelot method was obtained ... 

In this section, we review a method used over more than 150 years, and named after its inventor, Marcellin Berthelot [44]. The Berthelot method consists in the following (Fig. 5c). A vessel is filled with liquid and sealed with a remaining gas bubble. The vessel is then warmed up until the bubble dissolves completely from the dissolution temperature T, the liquid density is deduced. The vessel is then cooled down, the liquid sticks to its walls and the pressure decreases. 

Berthelot method has the advantage of generating tension in a static, macroscopic volume of liquid this characteristic facilitates mechanical and... 

Berthelot method in water inclusions in quartz [45]. The inclusions appear to give a much more negative Pcav But one has to remember that the liquid density only is known (assuming that the inclusions keep a constant volume and remain sealed), and that the pressure is deduced with an extrapolated EoS. Therefore, a direct measurement of the liquid density at the nucleation threshold has been performed in the acoustic experiment [52], thanks to a fiber optic probe hydrophone [51], Figure 8b presents a comparison of the acoustic and inclusion measurements in terms of density. The solid bullets are direct measurements acquired with the hydrophone and they compare well in trend and magnitude with pressure estimates that were converted to density with an EoS, but the major discrepancy with the inclusions is persistent. 

Formic acid [64-18-6] (methanoic acid) is the first member of the homologous series of alkyl carboxyHc acids. It occurs naturally ia the defensive secretions of a number of insects, particularly of ants. Although the acid nature of the vapors above ants nests had been known since at least 1488, the pure acid was not isolated until 1671, when the British chemist John Ray described the isolation of the pure acid by distillation of ants (1). This remained the main preparative method for more than a century until a convenient laboratory method was discovered by Gay-Lussac (2). The preparation of formates using carbon monoxide was described by Berthelot in 1856. 

A new kinetic enzymatic method for the routine determination of urea in semm has been evaluated. This method is based upon an enzymatic reaction and formation of a coloured complex. The method is based on a modified Berthelot reaction. The reaction was monitored specRophotomebically at 700 nm (t = 25 0.1 °C). The optimal pH value, chosen for the investigation of complex, is 7.8. 

In 1869 Berthelot- reported the production of styrene by dehydrogenation of ethylbenzene. This method is the basis of present day commercial methods. Over the year many other methods were developed, such as the decarboxylation of acids, dehydration of alcohols, pyrolysis of acetylene, pyrolysis of hydrocarbons and the chlorination and dehydrogenation of ethylbenzene." ... 

One of the first methods of polymerizing vinyl monomers was to expose the monomer to sunlight. In 1845, Blyth and Hoffman [7] obtained by this means a clear glassy polymeric product from styrene. Berthelot and Gaudechon [8] were the first to polymerize ethylene to a solid form and they used ultraviolet (UV) light for this purpose. The first demonstration of the chain reaction nature of photoinitiation of vinyl polymerization was done by Ostromislenski in 1912 [9]. He showed that the amount of poly(vinyl bromide) produced was considerably in excess of that produced for an ordinary chemical reaction. 

Berthelot showed that the mean compressibility between 1 and 2 atm. does not differ appreciably from that between 0 and 1 atm. in the case of permanent gases, and either may be used within the limits of experimental error. But in the case of easily liquefiable gases the two coefficients are different. According to Berthelot and Guye the value of aJ can be determined from that of aj by means of a small additive correction derived from the critical data, and the linear extrapolation then applied Gray and Burt consider, however, that this method may lead to inaccuracies, and consider that the true form of the isothermal can only be satisfactorily ascertained by the experimental determination of a large number of points, followed by graphical extrapolation. 

The method in use previous to Berthelot s depended on the results of the Porus Plug experiments of Joule and Kelvin. 

Marcellin Berthelot, Legons sur les methodes generates de synthese en chimie organique (Paris Gauthier-Villars, 1864) 453454, n. 5, and 521523. 

Static-bomb combustion calorimetry is particularly suited to obtaining enthalpies of combustion and formation of solid and liquid compounds containing only the elements C, H, O, and N. The origins of the method can be traced back to the work of Berthelot in the late nineteenth century [18,19]. 

The first reported attempt to use fluorine in calorimetric measurements is probably Berthelot and Moissan s study of the reaction between K.2SC>3(aq) and F2(g), in 1891 [ 19,120]. Modem fluorine bomb calorimetry, however, was started in the 1960s by Hubbard and co-workers [110,111,121], while in the same period Jessup and Armstrong and their colleagues [ 109,115-117] developed the method of fluorine flame calorimetry to a high degree of accuracy and precision. 

Prior to the breakthrough by E.Buchner s investigations, Berthelot had tried to demonstrate cell-free (and thus chemical or enzymatic nature of the) conversion of sugar to alcohol in the 1850 s, but indeed his approach could not be successful, as was obvious from Pasteur s clarification of the manifold somces of microbial infection, notably inoculation from the air. It was these findings which were a condition for Buchner s concept to exclude microorganisms (at least to an essential extent, as he was able to show) in his experiments. The progress in understanding and methods thus was necessaiy for the chemical approach, even if Pasteur opposed it himself... 

P) expressed as P 100(1 —cosA)/ (l-cosA0), where (AQ) is the angle of recoil of reference explosive] 25) PATR 2700, Vol 2(1962), p B6-R (Ballistic measuring methods) B105-L (Berthelot Characteristic Product) 26) PATR 2700,... 

Calculation of deton vel by the formula of Berthelot) 92-6 (Exptl detn of deton vel by chronographs of LeBoulenge and Mettegang) 97-8 (Detn by accelograph of Duprez) 98-100 (Detn by. Dautriche method) 33) D.P. MacDougall et al, "The Rate of Detonation of Various Explosive Compounds and Mixtures , OSRD 5611(1946) 34) C.R. Niesewanger 8c... 

Statistical and computational methods have been used to quantify structure-activi relationships leading to quantitative structure-activity relationships (QSAR). The concqpt of QSAR can be dated back to the work of Crum, Brown and Fraser from 1868 to 1869, and Richardson, also in 1869. Many notable papers were published in the period leading up to the twentieth century by men such as Berthelot and Jungfleisch in 1872, Nemst in 1891, Ov ton in 1897 and Meyer in 1899 (7). Professor Corwin Hansch is now regarded by many as the father of QSAR, because of his work in the development of new and innovative techniques for QSAR. He and his co-woikers produced a paper that was to be known as the birtii of QSAR, and was oititled "Correlation of biological activity of phenoxyacetic acids with Hammett substituent constants and partition coefficients" (2). 

In this section and in the rest of the article we will use the notations and results of Berthelot, Breen and Messing from their book Theorie de Dieudonne Cnstalline II. In fact we will use the methods developed there to define a Dieudonne module theory and prove some theorems on it. 

Hess of Austria pointed out in 1873 the defect of both expressions and introduced the concept of 11 brisance" as the work done by a unit of wt of exp] in unit time. He assumed a numerical value for this as the quotient of the Berthelot Characteristic Product and the time consumed by the expln. This period of time was to be ealed from the experimentally detd vel of deton. However, this method of detg the work done by an expl was not satisfactory. Still less satisfactory was the formula of Bichel published in Gliickauf 41, 465(1905) and mentioned in Ref 2, p 153... 

MgCj, tetragonal crysts, which are decompd by w into CaHj and Mg(OH)r Was first prepd in 1866 by Berthelot (Ref 2) by heating Mg pdr in stream of C,Ha. Many other methods are listed in Beil, but it seems that heating of Mg pdr to ca 450° in a stream of acetylene is the simplest method (Ref 3) I was claimed fhar M G. rnnvprfpfl m Utr.G ar i n 00°... 

Less dangerous is the method of combustion in a closed bomb (calorimetric bomb) contg a large amt of compressed oxygen, followed by analysis of resulting gas for the amt of COz formed on combustion of C. This method was first proposed by Berthelot (Ref 1) and modified by Hempel (Ref 2). Badoche (Ref 3) and Burlot (Ref 4) investigated the method and found it to be satisfactory... 

In both Berthelot s method and its modifications, the gases produced on combustion or expln are analyzed after they are removed from the bomb. Thomas (Ref 10) found that it is simpler to analyze the gases directly in the bomb without transferring them to another vessel. This method is essentially as fellows ... 

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