scholarly journals IV. On the mechanical stretching of liquids : an experi­mental determination of the volume-extensibility of ethyl alcohol

1892 ◽  
Vol 50 (302-307) ◽  
pp. 423-424

After adverting to the three known methods of subjecting a liquid tension, viz., (i) the method of the inverted barometer, (ii) the centrifugal method devised by Osborne Reynolds, (iii) the method of cooling discovered in 1850 by Berthelot, and pointing out that the first two afford means of measuring stress but not strain, while the third gives a measure of strain but not stress, the author proceeds to describe the manner in which he had used the method of Berthelot in combination with a new mode of determining the stress, and had succeeded in obtaining simultaneous measures of tensile stress and strain for ethyl alcohol up to a tension of more than 17 atmospheres, or 255 lbs. per square inch.

1994 ◽  
Vol 338 ◽  
Author(s):  
L. Maniguet ◽  
M. Ignat ◽  
M. Dupeux ◽  
J.J. Bacmann ◽  
Ph. Normandon

ABSTRACTThe determination by X-ray diffraction of the elastic strain tensors and the corresponding stress tensors in patterned lines of tungsten has been performed to investigate the effect of various passivation. For unpassivated lines, the stresses are biaxial and decrease with decreasing line width. Passivation over patterned lines results in triaxial tensile stress. The stress along the line is not changed by the passivation. The stress across the line decreases as the line width decreases. The third component of stress, perpendicular to the surface, which appears with the passivation, increases with decreasing line width. High compressive intrinsic stress in the passivation does not result in high tensile stress in the metal line.


Three methods are known by which a liquid may be subjected to a bodily tension. (1) The method of the inverted barometer , familiar to most physicists, by which, with care, a mercury column of many times the barometric height may be supported by its adhesion to the top of the tube. In such a column the hydrostatic pressure is negative above the barometric height, or the liquid above this level is in a state of tension. This tension increases with the height and is propagated in all directions to the walls of the tube. When the upper part of the tube is made elliptical in cross-section and of thin glass, its yielding to the inward pull may be easily observed. (2) The centrifugal method , devised by Professor Osborne Reynolds, in which a U-tube, ABCD, of glass, closed at both ends, contains air-free liquid, ABC, and vapour, CD. This tube is fixed to a suitable board and whirled about an axis, O, a little beyond the end, A, and perpendicular to the plane of the board. If CE (see figure) be the arc of a circle described about O, then while rotation continues the liquid between E and A is in a state of tension, increasing from zero (if we ignore the vapour-pressure) at E to a maximum at A. By this method Professor Osborne Reynolds has subjected water to a tension of about 5 atmospheres or 72·5 pounds per square inch, while the author, experimenting in the Cavendish Laboratory in 1886, succeeded in reaching, with alcohol, a tension of 7·9 atmospheres or 116 pounds per square inch, and, with strong sulphuric acid, 11·8 atmospheres or 173 pounds per square inch.


2000 ◽  
Vol 39 (05) ◽  
pp. 121-126 ◽  
Author(s):  
R. Werz ◽  
P. Reuland

Summary Aim of the study was to find out wether there is a common stop of growth of mandibular bone, so that no individual determination of the optimal time for surgery in patients with asymmetric mandibular bone growth is needed. As there are no epiphyseal plates in the mandibular bone, stop of growth cannot be determined on X-ray films. Methods: Bone scans of 731 patients [687 patients (324 male, 363 female) under 39 y for exact determination of end of growth and 44 (21 male, 23 female) patients over 40 y for evaluation of nongrowth dependant differences in tracer uptake] were reviewed for the study. All the patients were examined 3 hours after injection of 99mTc-DPD. Tracer uptake was measured by region of interest technique in different points of the mandibular bone and in several epiphyseal plates of extremities. Results: Tracer uptake in different epiphyseal plates of the extremities shows strong variation with age and good correlation with reported data of bone growth and closure of the epiphyseal plates. The relative maximum of bone activity is smaller in mandibular bone than in epiphyseal plates, which show well defined peaks, ending at 15-18 years in females and at 18-21 years in males. In contrast, mandibular bone shows no well defined end of growing but a gradually reduction of bone activity which remains higher than bone activity in epiphyseal plates over several years. Conclusion: No well defined end of growth of mandibular bone exists. The optimal age for surgery of asymmetric mandibular bone growth is not before the middle of the third decade of life, bone scans performed earlier for determination of bone growth can be omitted. Bone scans performed at the middle of the third decade of life help to optimize the time of surgical intervention.


2019 ◽  
Vol 7 (1) ◽  
pp. 9-20
Author(s):  
Inna Yeung

Choice of profession is a social phenomenon that every person has to face in life. Numerous studies convince us that not only the well-being of a person depends on the chosen work, but also his attitude to himself and life in general, therefore, the right and timely professional choice is very important. Research about factors of career self-determination of students of higher education institutions in Ukraine shows that self-determination is an important factor in the socialization of young person, and the factors that determine students' career choices become an actual problem of nowadays. The present study involved full-time and part-time students of Institute of Philology and Mass Communications of Open International University of Human Development "Ukraine" in order to examine the factors of career self-determination of students of higher education institutions (N=189). Diagnostic factors of career self-determination of students studying in the third and fourth year were carried out using the author's questionnaire. Processing of obtained data was carried out using the Excel 2010 program; factorial and comparative analysis were applied. Results of the study showed that initial stage of career self-determination falls down on the third and fourth studying year at the university, when an image of future career and career orientations begin to form. At the same time, the content of career self-determination in this period is contradictory and uncertain, therefore, the implementation of pedagogical support of this process among students is effective.


Author(s):  
E.A. Derkach , O.I. Guseva

Objectives: to compare the accuracy of equations F.P. Hadlock and computer programs by V.N. Demidov in determining gestational age and fetal weight in the third trimester of gestation. Materials: 328 patients in terms 36–42 weeks of gestation are examined. Ultrasonography was performed in 0–5 days prior to childbirth. Results: it is established that the average mistake in determination of term of pregnancy when using the equation of F.P. Hadlock made 12,5 days, the computer program of V.N. Demidov – 4,4 days (distinction 2,8 times). The mistake within 4 days, when using the equation of F.P. Hadlock has met on average in 23,1 % of observations, the computer program of V.N. Demidov — 65,9 % (difference in 2,9 times). The mistake more than 10 days, took place respectively in 51,7 and 8,2 % (distinction by 6,3 times). At a comparative assessment of size of a mistake in determination of fetal mass it is established that when using the equation of F.P. Hadlock it has averaged 281,0 g, at application of the computer program of V.N. Demidov — 182,5 g (distinction of 54 %). The small mistake in the mass of a fetus which isn't exceeding 200 g at application of the equation of F.P. Hadlock has met in 48,1 % of cases and the computer program of V.N. Demidov — 64,0 % (distinction of 33,1 %). The mistake exceeding 500 g has been stated in 18 % (F.P. Hadlock) and 4,3 % (V.N. Demidov) respectively (distinction 4,2 times). Conclusions: the computer program of V.N. Demidov has high precision in determination of term of a gestation and mass of a fetus in the III pregnancy.


Author(s):  
Chakravarthi Ram-Prasad

The Introduction outlines the various chapters. It then situates the question of ‘body’ in the modern Western philosophical tradition following Descartes, and argues that this leaves subsequent responses to come under one of three options: metaphysical dualism of body and subject; any anti-dualist reductionism; or the overcoming of the divide. Describing the Phenomenology of Merleau-Ponty as a potent example of the third strategy, the Introduction then suggests his philosophy will function as foil to the ecological phenomenology developed and presented in the book. Moreover, one approach within the Western Phenomenological tradition, of treating phenomenology as a methodology for the clarification of experience (rather than the means to the determination of an ontology of the subject) is compared to the approach in this book. Since classical India, while understanding dualism, did not confront the challenge of Descartes (for better or for worse), its treatment of body follows a different trajectory.


1936 ◽  
Vol 34 (4) ◽  
pp. 504-505 ◽  
Author(s):  
J. C. Abels
Keyword(s):  

Author(s):  
Sanaa Aljamani ◽  
Callum Youngson ◽  
Fadi Jarad ◽  
Francis O’Neill

Abstract Purpose Recently we described mapping of the lingual nerve clinically in patients using electrical nerve stimulation. This paper reports results of a larger study with inter- and intra-observer reliability and comparison with positional measurements from magnetic resonance imaging (MRI). Methods In 50 healthy participants, measurements were taken when subjects felt a tingling sensation in the tongue induced by a stimulation probe over the lingual nerve. Three positions were measured in relation to the third molar. Measurement reliability was tested for both inter-observer and intra-observer agreement and positional data of the lingual nerve measured clinically was also compared with nerve position as measured from MRI scans. Results Out of 50 participants, 96 nerves (49 = left/47 = right) were included in the study. The lingual nerve was identified in 90% (87) of this sample. The mean of height of the nerve in points A, B and C were 9.64 mm, 10.77 mm and 12.34 respectively. Inter-and intra-observer agreement was considered to be good to excellent (ICC = 0.8–0.96). Agreement between nerve mapping measured values and MRI measured values was good (ICC < 0.6). Conclusion This technique may prove useful for the clinical determination of lingual nerve position prior to procedures in the third molar region.


2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Shilan A. Omer ◽  
Nabil A. Fakhre

In this study, three simple and accurate spectrophotometric methods for simultaneous determination of pyriproxyfen and chlorothalonil residues in cucumbers and cabbages grown in experimental greenhouse were studied. The first method was based on the zero-crossing technique measurement for first and second derivative spectrophotometry. The second method was based on the first derivative of the ratio spectra. However, the third method was based on mean centering of ratio spectra. These procedures lack any previous separation steps. The calibration curves for three spectrophotometric methods are linear in the concentration range of 1–30 μg·mL−1 and 0.5–7 μg·mL−1 for pyriproxyfen and chlorothalonil successively. The recoveries ranged from 82.12–97.40% for pyriproxyfen and 81.51–97.04% for chlorothalonil with relative standard deviations less than 4.95% and 5.45% in all instances for pyriproxyfen and chlorothalonil, respectively. The results obtained from the proposed methods were compared statistically by using one-way ANOVA, and the results revealed there were no significant differences between ratio spectra and mean centering methods with the zero-crossing technique. The proposed methods are successfully applied for the simultaneous estimation of the residue of both pesticides in cucumber and cabbage samples.


1965 ◽  
Vol 20 (4) ◽  
pp. 318-322 ◽  
Author(s):  
Irmgard Ziegler ◽  
M. Feron

In the eyes of male and female flies a quantitative determination of the tetrahydropterin, the corresponding dihydro-compound (Sepiapterin) and of xanthommatin from 0—5 days after hatching was made. The increase of xanthommatin almost stops 24 hours after hatching; about 13 μg are present after that time. The tetrahydropterin, after a drastic increase during the first 24 hours, remains at a level of about 1,1 — 1,2 µg. In contrast the dihydrocompound which is nearly absent at the time of hatching is deposited on the eye-granules between the third and fifth day. At that time, especially in the male the dihydropterin/tetrahydropterin ratio is increased. Starvation during the first 24 hours has essentially no effect on the amount of xanthommation whereas the amount of pterins is markedly reduced.


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