scholarly journals Flame speeds in the “inflammation” and “detonation” of moist carbonic oxide-oxygen mixtures

1931 ◽  
Vol 130 (814) ◽  
pp. 542-551
Keyword(s):  
Initial Phase ◽  
Horizontal Tube ◽  
Complete Data ◽  
The Other ◽  
Explosive Mixture ◽  
Explosion Limits ◽  
Oscillatory Movement ◽  
Set Up

Seeing that hitherto our knowledge of the flame speeds involved in the “inflammation” and “detonation” of carbonic oxide-oxygen mixtures has been mainly confined to those of the theoretical 2CO+O 2 mixture, and that complete data over the whole “explosion range” are needed for the determination of questions relating to the combustion of carbonic oxide, we have lately carried out experiments with a view to suppyling the deficiency; and this paper embodies the results thereof. Experimental. A.-Flame Speeds in the Initial Phase of "Inflammation." It may be recalled that when a quiescent explosive mixture is ignited at the open end of a horizontal tube, the other end being closed, a slow and usually uniform flame movement is initially set up. Except in mixtures very near to one or other of the explosion limits, this initial phase is soon succeeded by an oscillatory movement during which the flame swings backwards and forwards, usually with increasing amplitude, until it is either extinguished, by swinging too far backwards into its own products of combustion, or gives rise to a must accelerated movement, may be ending up in "detonation" if sufficiently accelerated during a forward swing.

Determination of Stresses in Cemented Lap Joints

1953 ◽  
Vol 20 (3) ◽  
pp. 355-364
Author(s):  
R. W. Cornell
Keyword(s):  
Differential Equations ◽  
Infinite Number ◽  
Lap Joints ◽  
The Other ◽  
Complete Analysis ◽  
Stress Distributions ◽  
Lap Joint ◽  
Analogy Method ◽  
Set Up

Abstract A variation and extension of Goland and Reissner’s (1) method of approach is presented for determining the stresses in cemented lap joints by assuming that the two lap-joint plates act like simple beams and the more elastic cement layer is an infinite number of shear and tension springs. Differential equations are set up which describe the transfer of the load in one beam through the springs to the other beam. From the solution of these differential equations a fairly complete analysis of the stresses in the lap joint is obtained. The spring-beam analogy method is applied to a particular type of lap joint, and an analysis of the stresses at the discontinuity, stress distributions, and the effects of variables on these stresses are presented. In order to check the analytical results, they are compared to photoelastic and brittle lacquer experimental results. The spring-beam analogy solution was found to give a fairly accurate presentation of the stresses in the lap joint investigated and should be useful in analyzing other cemented lap-joint structures.

A feedback reactor with continuous injection of one reaction component using spectrophotometric indication I

1988 ◽  
Vol 53 (5) ◽  
pp. 929-938
Author(s):  
František Skopal
Keyword(s):  
Time Dependence ◽  
Rate Constants ◽  
The Other ◽  
Experimental Apparatus ◽  
Set Up ◽  
Continuous Injection ◽  
Reaction Component

The time dependence of the volume of solution of one reaction component injected continuously to the solution of the other reaction component is derived for the case that the injection is controlled by feedback to hold the absorbance of the reaction mixture constant. An experimental apparatus based on this principle has been set up and its function tested on two 2nd order reactions, whereby the theoretical relations derived for the determination of the rate constants have also been verified.

scholarly journals Automation and Software of the Wanschaff Vertical Circle at Goloseevo

1986 ◽  
Vol 109 ◽  
pp. 463-464
Author(s):  
A.S. Kharin ◽  
L.A. Kukharskij ◽  
P.F. Lazorenko ◽  
N.F. Minyajlo ◽  
M.L. Tsesis
Keyword(s):  
Vertical Axis ◽  
Automatic Machine ◽  
The Other ◽  
Vertical Circle ◽  
Other Information ◽  
Set Up

The Wanschaff vertical circle, set up at Goloseevo in 1949 was built in 1914. The instrument was originally equiped with four visual microscopes for reading the circle, with a visual eyepiece micrometer, and with two levels for the determination of the inclination of the vertical axis. After the instrument had been installed in a new pavilion in 1972, the visual microscopes were replaced by photographic devices, and a semi-automatic machine for measuring the circle readings with output on punched tape was developed. In 1973,the eyepiece micrometer was equiped with a precision potentiometer of the type which together with an automatic voltmeter of the type the digitizer micrometer readings punches them on tape. The other information is punched on cards by the operator at the data desk.

scholarly journals The theory of flame motion

1930 ◽  
Vol 126 (802) ◽  
pp. 393-405 ◽  
Keyword(s):  
Detailed Analysis ◽  
Theoretical Aspect ◽  
Horizontal Tube ◽  
Experimental Methods ◽  
The Other ◽  
Uniform Motion ◽  
General Description ◽  
Square Root ◽  
Explosive Mixture ◽  
Original Formula

The motion of flame has been extensively investigated by experimental methods. The theoretical aspect of one mode of propagation has been studied by D. L. Chapman and by Jouguet. Their observations are limited to the phenomenon known as detonation. For the slower and more usual propagation of flame there is a well-known formula due to Mallard and Le Chatelier. It refers to the horizontal propagation of flame through a still mixture under such circumstances that the pressure produced by the combustion is freely vented into the atmosphere. That is to say, the explosive mixture is ignited at the open end of a horizontal tube, the tube being closed at the other end to shield the mixture from any external currents. This formula was intended as a tentative and general description, without detailed analysis, of the initial, uniform motion of the flame. It is based on the assumption that the trans­mission of flame depends on a balance between the conduction of heat from layer to layer and the cooling. In Mallard's original formula|| the velocity of the flame was held to be inversely proportional to the square root of the cooling due to the wall of the tube; but this relation disappears in the final, joint result of these authors, who wrote their formula V = K T - t / t -θƒ(T. t ), or, tentatively, V=K.L/ c .T - t / t -θ, which becomes V = K . L .Q/ c 2 ( t -θ),

The Determination of the Expansion Forces in Piping by Model Test

1939 ◽  
Vol 6 (1) ◽  
pp. A21-A24
Author(s):  
Harold W. Semar
Keyword(s):  
Steam Turbine ◽  
Model Test ◽  
The Other ◽  
Inlet Pipe ◽  
Full Size ◽  
Pipe Expansion ◽  
Measured Amount ◽  
Set Up

Abstract The paper describes apparatus for testing models of piping installations to determine the forces set up in the full-size installation due to expansion. The method consists in fixing one end of the model in a slide which can be moved a measured amount, and measuring the forces at the other end by means of a fixture which holds that end rigidly in place and permits measurement of six forces in three coordinate planes, which are the equivalent of forces in coordinate directions plus moments in coordinate planes. The slide of the movable end is placed so that its direction of motion coincides with the direction of the pipe expansion. A complete example is given showing the steps in determining the end reactions of an inlet pipe for a steam turbine.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

Determination of the Burgers vector of a dislocation in a Fe-Mn alloy by weak-beam image in HVEM

1978 ◽  
Vol 36 (1) ◽  
pp. 330-331
Author(s):  
Y. Ishida ◽  
H. Ishida ◽  
K. Kohra ◽  
H. Ichinose
Keyword(s):  
High Order ◽  
Simulation Technique ◽  
The Other ◽  
Image Simulation ◽  
Diffraction Vector ◽  
Burgers Vector ◽  
Weak Beam ◽  
Beam Image ◽  
Edge Component

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.

Procedures for the Quantitative Determination of Autoprothrombin C

1962 ◽  
Vol 08 (03) ◽  
pp. 434-441 ◽  
Author(s):  
Edmond R Cole ◽  
Ewa Marciniak ◽  
Walter H Seegers
Keyword(s):  
Quantitative Determination ◽  
Plasma Sample ◽  
Quantitative Measure ◽  
The Other ◽  
Clotting Time ◽  
Bovine Plasma ◽  
Autoprothrombin C

SummaryTwo quantitative procedures for autoprothrombin C are described. In one of these purified prothrombin is used as a substrate, and the activity of autoprothrombin C can be measured even if thrombin is in the preparation. In this procedure a reaction mixture is used wherein the thrombin titer which develops in 20 minutes is proportional to the autoprothrombin C in the reaction mixture. A unit is defined as the amount which will generate 70 units of thrombin in the standardized reaction mixture. In the other method thrombin interferes with the result, because a standard bovine plasma sample is recalcified and the clotting time is noted. Autoprothrombin C shortens the clotting time, and the extent of this is a quantitative measure of autoprothrombin C activity.

Determination of Factor XIII Activity and of Factor XIII Inhibitors Using an Ammonium-Sensitive Electrode

1983 ◽  
Vol 50 (02) ◽  
pp. 563-566 ◽  
Author(s):  
P Hellstern ◽  
K Schilz ◽  
G von Blohn ◽  
E Wenzel
Keyword(s):  
Factor Xiii ◽  
Normal Subjects ◽  
The Other ◽  
Activity Measurement ◽  
Factor Xiii Deficiency ◽  
Assay Procedure ◽  
Stabilization Factor ◽  
Release Method ◽  
Sensitive Electrode

SummaryAn assay for rapid factor XIII activity measurement has been developed based on the determination of the ammonium released during fibrin stabilization. Factor XIII was activated by thrombin and calcium. Ammonium was measured by an ammonium-sensitive electrode. It was demonstrated that the assay procedure yields accurate and precise results and that factor XIII-catalyzed fibrin stabilization can be measured kinetically. The amount of ammonium released during the first 90 min of fibrin stabilization was found to be 7.8 ± 0.5 moles per mole fibrinogen, which is in agreement with the findings of other authors. In 15 normal subjects and in 15 patients suffering from diseases with suspected factor XIII deficiency there was a satisfactory correlation between the results obtained by the “ammonium-release-method”, Bohn’s method, and the immunological assay (r1 = 0.65; r2= 0.70; p<0.01). In 3 of 5 patients with paraproteinemias the values of factor XIII activity determined by the ammonium-release method were markedly lower than those estimated by the other methods. It could be shown that inhibitor mechanisms were responsible for these discrepancies.

Sign in / Sign up

Export Citation Format

Share Document