摘要:

A simple technique has been found for rendering visible the shock wave formed by an exploding wire after the shock has separated from the luminous contact surface. A small, plane mirror is placed just behind the wire so as to be perpendicular to the axis of the optical system. Thus the reflected image of the wire explosion coincides with the disturbance itself when seen through the slit by the camera lens. Rotating mirror pictures taken under these conditions show very clear outlines of the parabolic shock wave as it propagates ahead of the luminous contact surface. The separation of the shock and contact surface is complete by about one &mgr;sec. Beyond this time the shock is clearly nonluminous and ordinarily would not be visible. Comparison of shock trajectories with predictions from the similarity solutions for strong shock waves obtained by S. C. Lin may be interpreted as showing that the shock is receiving additional energy while traversing the early part of its path. After this phase both shock and contact surface accurately obey a parabolic law over intervals of several microseconds.

ISSN:0031-9171    

DOI:10.1063/1.1705893

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

To help put a lower limit on the sensitive time of organic liquids commonly used in bubble chambers a static electric field of 15 kv/cm was applied across a small propane bubble chamber which was then expanded in the conventional manner when a beam of 450 Mev protons was passed through it. The bubble density along the tracks was measured with both field on and field off. Within statistics (±4&percent;) no difference in bubble density was observed for the two cases.To interpret this result it is assumed that &dgr; rays produce bubbles if they deposit a certain minimum amount of energy within a critical volume of the liquid. It is then concluded from this experiment that either recombination effects are not important in bubble formation or that the recombination time of ions in a critical volume of propane is ≲ 10−11sec. This figure appears to represent a reasonable theoretical estimate of the sensitive time of propane, liquid hydrogen, and liquid helium.

ISSN:0031-9171    

DOI:10.1063/1.1705894

出版商:AIP    

年代:1958

数据来源: AIP

摘要:

The evaporation rate of a solid or liquid into a stream of gas flowing across its surface is considered as a function of surface temperature and of material and gas properties neglecting chemical reactions. One of the boundary conditions to be used at the interface between the gas and the solid (or liquid) is derived.

ISSN:0031-9171    

DOI:10.1063/1.1705895

出版商:AIP    

年代:1958

数据来源: AIP

ISSN:0031-9171    

DOI:10.1063/1.1705896

出版商:AIP    

年代:1958

数据来源: AIP

ISSN:0031-9171    

DOI:10.1063/1.1705897

出版商:AIP    

年代:1958

数据来源: AIP