scholarly journals Note on the boiling-point of sulphur

1908 ◽  
Vol 81 (548) ◽  
pp. 363-366 ◽  
Keyword(s):  
Boiling Point ◽  
Constant Pressure ◽  
Linear Expansion ◽  
Preceding Paper ◽  
Glass Tube ◽  
The Difference

As I have been partly to blame for the delay in the publication of the observations described in the preceding paper by Mr. N. Eumorfopoulos, it seems tight that I should make a brief statement, by way of apology, with regard to the object of the work and the causes which have led to the delay. The determination of the boiling-point of sulphur by Mr. E. H. Griffiths and myself in 1890 was made with the same air thermometer as that employed in my original experiments of 1887, and gave the same value for the difference-coefficient of the platinum thermometer. The result depended, however, on the scale of the constant-pressure air thermometer, and the correction for the expansion of the bulb was deduced from observations of the linear expansion over the range 0° to 500°C. of a piece of glass tube from which the bulb was made. Some uncertainty was introduced also by changes in the volume of the bulb at a temperature of 450°C.

scholarly journals XXVII. On the expansion by heat of metals and alloys

1866 ◽  
Vol 156 ◽  
pp. 861-881 ◽  
Keyword(s):  
Linear Expansion ◽  
Metals And Alloys ◽  
Different Temperatures ◽  
The Difference

In a memoir “On the Expansion by Heat of Water and Mercury”*, I described a method of determining the expansion of bodies by weighing them in water at different temperatures. This method was chosen on account of its yielding accurate results with comparatively small quantities, for to purify large quantities of metal would entail immense labour and expense; so much so, in fact, that to purify sufficient quantities to make bars for the determination of the linear expansion would be practically impossible. On determining the expansion of the metals by this method, I found that they did not expand regularly between 0° and 100°. The difference, however, between the rates of expansion between 0° and 50° and 50° and 100° was found to be so great that part of it might be possibly attributed to errors in the determination of the coefficients of expansion of water, as the coefficients of expansion of the metals are comparatively small when compared with those of water. Now, although the coefficient of expansion of mercury when determined by this method agrees with Regnault's value, yet on account of this value being large, small errors in the water coefficients will not materially influence it ; for the volume of water at 4°=1·0000, at 100°=1·04316, that of mercury at 0°=l·0000, at 100°=1·01815, and that of copper, for instance, at 0°=1·00000, at 100°=1004998, showing that the expansion of copper is very small compared with that of water or mercury.

Determination of heats of vaporization and some other thermodynamic properties for four substituted hydrocarbons

1982 ◽  
Vol 47 (2) ◽  
pp. 543-549 ◽  
Author(s):  
Václav Svoboda ◽  
Vladimíra Charvátová ◽  
Vladimír Majer ◽  
Vladimír Hynek
Keyword(s):  
Thermodynamic Properties ◽  
Temperature Dependence ◽  
Constant Pressure ◽  
Pressure Curve ◽  
Saturated Vapour Pressure ◽  
Vapour Pressure Curve ◽  
The Difference ◽  
Cohesive Energies ◽  
Heats Of Vaporization

The temperature dependence of heats of vaporization and some other derived thermodynamic properties were determined for four substituted hydrocarbons, viz. 2,2,4-trimethylpentane,1-octene, ethylbenzene and n-butylbenzene. The temperature dependence of heats of vaporization was measured and, on the basis of these data, the values of standard heats of vaporization, internal and cohesive energies, entropies of vaporization and the difference of heat capacities of liquid and vapour at constant pressure and along the saturated vapour pressure curve were computed.

scholarly journals On the use of the barometric thermometer for the determina­tion of relative heights

1851 ◽  
Vol 5 ◽  
pp. 597-599
Keyword(s):  
Boiling Point ◽  
Theoretical Foundation ◽  
Barometric Pressure ◽  
Boiling Temperature ◽  
Comparison Of Results ◽  
Boiling Points ◽  
The Alps ◽  
The Mean ◽  
The Difference

The objects of this communication, as stated by the author, are, first, to show the theoretical foundation of the very simple law pointed out by Professor Forbes, according to which the difference of the boiling temperature of water at two stations is connected with their difference of level ; and next, to test the accuracy of this law by a comparison of results deduced from his own observations on the boiling-point of water at different stations among the Alps of Savoy, Piedmont and Switzerland, with the heights of the same stations as determined by other observers and by different means ; and thus to arrive at a just conclusion with respect to the value of the barometric thermometer as an instrument for determining differences of level. Combining DeLuc’s formula reduced to English units, b = 99 log 10 β - 60.804, .899 where b is the variable boiling-point on Fahrenheit’s scale and β the corresponding barometric pressure, with the formula of Laplace for the determination of the difference in level of two stations from barometric observations, he obtains the formula H = 547.99 ( b - b' ) { 1 + ( t - 32°) .00222 } , where b and b' are the boiling-points on Fahrenheit’s scale at-the two stations, t the mean temperature of the air at the stations, and H their difference of level in English feet.

FRACTIONAL DETERMINATIONS OF URINARY 17-KETOSTEROIDS IN HYPEREMESIS GRAVIDARUM

1962 ◽  
Vol 41 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Pentti A. Järvinen ◽  
Sykkö Pesonen ◽  
Pirkko Väänänen
Keyword(s):  
Hyperemesis Gravidarum ◽  
First Trimester ◽  
Control Group ◽  
Before And After ◽  
Daily Urine ◽  
First Trimester Of Pregnancy ◽  
The Difference

ABSTRACT The fractional determination of 17-ketosteroids in the daily urine was performed in nine cases of hyperemesis gravidarum and in four control cases, in the first trimester of pregnancy both before and after corticotrophin administration. The excretion of total 17-KS is similar in the two groups. Only in the hyperemesis group does the excretion of total 17-KS increase significantly after corticotrophin administration. The fractional determination reveals no difference between the two groups of patients with regard to the values of the fractions U (unidentified 17-KS), A (androsterone) and Rest (11-oxygenated 17-KS). The excretion of dehydroepiandrosterone is significantly higher in the hyperemesis group than in the control group. The excretion of androstanolone seems to be lower in the hyperemesis group than in the control group, but the difference is not statistically significant. The differences in the correlation between dehydroepiandrosterone and androstanolone in the two groups is significant. The high excretion of dehydroepiandrosterone and low excretion of androstanolone in cases of hyperemesis gravidarum is a sign of adrenal dysfunction.

THE SUBJECT FIELD OF INSTITUTIONAL EDUCATION: THE SENSE AND PROSPECTS OF DEVELOPMENT IN UKRAINE

2020 ◽  
pp. 25-38
Author(s):  
Irina Mordous
Keyword(s):  
Decisive Role ◽  
Subject Field ◽  
National Education ◽  
Progressive Development ◽  
Separate Area ◽  
Economic Transformations ◽  
The Difference ◽  
The Individual ◽  
Political Economic

The development of modern civilization attests to its decisive role in the progressive development of institutions. They identified the difference between Western civilization and the rest of the world. Confirmation of the institutional advantages of the West was its early industrialization. The genesis and formation of institutionalism in its ideological and conceptualmethodological orientation occurs as a process alternative to neoclassic in the context of world heterodoxia, which quickly spread in social science. Highlighting institutional education as a separate area of sociocultural activity is determined by the factor of differentiation of institutional theory as a whole. A feature of institutional education is its orientation toward the individual and his/her transformation into a personality. The content of institutional education is revealed through the analysis of the institution, which includes a set of established customs, traditions, ways of thinking, behavioral stereotypes of individuals and social groups. The dynamics of socio-political, economic transformations in Ukraine requires a review of the foundations of national education and determination of the prospects for its development in the 21st century in the context of institutionalism.

scholarly journals Possibility of Human Gender Recognition Using Raman Spectra of Teeth

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3983
Author(s):  
Ozren Gamulin ◽  
Marko Škrabić ◽  
Kristina Serec ◽  
Matej Par ◽  
Marija Baković ◽  
...  
Keyword(s):  
Raman Spectra ◽  
Principal Component ◽  
Support Vector ◽  
Gender Recognition ◽  
Proof Of Concept ◽  
Male And Female ◽  
Tooth Type ◽  
Tooth Apex ◽  
The Difference

Gender determination of the human remains can be very challenging, especially in the case of incomplete ones. Herein, we report a proof-of-concept experiment where the possibility of gender recognition using Raman spectroscopy of teeth is investigated. Raman spectra were recorded from male and female molars and premolars on two distinct sites, tooth apex and anatomical neck. Recorded spectra were sorted into suitable datasets and initially analyzed with principal component analysis, which showed a distinction between spectra of male and female teeth. Then, reduced datasets with scores of the first 20 principal components were formed and two classification algorithms, support vector machine and artificial neural networks, were applied to form classification models for gender recognition. The obtained results showed that gender recognition with Raman spectra of teeth is possible but strongly depends both on the tooth type and spectrum recording site. The difference in classification accuracy between different tooth types and recording sites are discussed in terms of the molecular structure difference caused by the influence of masticatory loading or gender-dependent life events.

scholarly journals Influence of Erythrocytes on Direct Potentiometric Determination of Sodium and Potassium

1983 ◽  
Vol 20 (2) ◽  
pp. 116-120 ◽  
Author(s):  
P Bijster ◽  
H L Vader ◽  
C L J Vink
Keyword(s):  
Whole Blood ◽  
Potassium Concentration ◽  
Reference Electrode ◽  
Sodium Concentration ◽  
General Phenomenon ◽  
Liquid Junction ◽  
Direct Potentiometry ◽  
The Difference ◽  
Sodium And Potassium

We have shown that the sodium concentration in whole blood measured by direct potentiometry is higher than in plasma. The ‘erythrocyte-effect’, already described by Siggaard Andersen, is most pronounced for instruments equipped with a reference electrode with an open static liquid junction and is thus a general phenomenon. Instruments with a modified liquid junction show less interference. The same phenomenon appears for the determination of the potassium concentration, although the difference between whole blood and plasma, when measured with instruments equipped with a modified liquid junction, can be neglected in practice.

Method for the simultaneous quantification of n-hexane metabolites: application to n-hexane metabolism determination

1996 ◽  
Vol 15 (6) ◽  
pp. 497-503 ◽  
Author(s):  
T. Soriano ◽  
M. Menéndez ◽  
P. Sanz ◽  
M. Repetto
Keyword(s):  
Similar Pattern ◽  
Analytical Procedure ◽  
Daily Basis ◽  
Practical Application ◽  
Simultaneous Quantification ◽  
Exposed Workers ◽  
Before And After ◽  
Time Requirements ◽  
The Difference

1 The described analytical procedure permits the simultaneous determination of the main n-hexane meta bolites in urine. 2-Hexanone, 2-hexanol, 2, 5-hexanediol and 2, 5-hexanedione, were chosen to dose the rats used in this study. All urine samples were collected and analysed on a daily basis, before and after acidic hydrolysis (pH 0.1) by GC/MS. 2-Hexanone, 2, 5-dimethylfurane, γ-valerolac tone and 2, 5-hexanedione were determined before hydro lysis ; 2-hexanol and 2, 5-hexanediol, after hydrolysis; and 5-hydroxy-2-hexanone and 4, 5-dihydroxy-2-hexanone were calculated by the difference between γ-valerolactone and 2, 5-hexanedione with and without hydrolysis, respectively. 2 A metabolic scheme was proposed reflecting the biotransformations undergone by the four compounds assayed. We consider 2, 5-dimethylfurane as a 'true metabolite' because the quantities detected were always greater before hydrolysis. 3 It has been reported that human and rat n-hexane metabolism follow a similar pattern. Therefore, as a practical application and without increasing either sample or time requirements, the simultaneous quantifi cation of the different metabolites and their excretion profile could provide better information about the metabolic situation of exposed workers than the determi nation of 2, 5-hexanedione alone. According to our experimental results, 4, 5-dihydroxy-2-hexanone itself would be a good toxicity indicator.

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