I remember using polypropylene prusik rope as
well. Tenstron was the preferred brand.
Keith is correct. The physical mechanisms behind
fluorescence and phosphorescence are different. Fluorescence occurs
by quantum-mechanically allowed transitions within the electronic
states of the material and happens essentially
instantaneously. Phosphorescence involves a so-called "forbidden"
electronic transition, which can still happen but is very much slower.
Mark
At 10:04 AM 6/3/2011, Keith Goggin wrote:
The dolphins are safe! A fluorescent material glows under a UV
lamp, but stops glowing as soon as the lamp is turned off. A
phosphorescent material keeps glowing for a while afterwards.
;-)
From: John P Brooks <jpbrook...@sbcglobal.net>
To: Cavers Texas <texascavers@texascavers.com>; Mixon Bill
<bmixon...@austin.rr.com>
Sent: Thu, June 2, 2011 10:59:55 PM
Subject: Re: [Texascavers] fluorescent rope
You better go kill a dolphin...you were wrong:
"Fluorescence is the emission of light by a substance that has
absorbed light or other electromagnetic radiation of a different
wavelength. [1]. It is a form of luminescence. In most cases,
emitted light has a longer wavelength, and therefore lower energy,
than the absorbed radiation. However, when the absorbed
electromagnetic radiation is intense, it is possible for one
electron to absorb two photons; this two-photon absorption can lead
to emission of radiation having a shorter wavelength than the
absorbed radiation.
The most striking examples of fluorescence occur when the absorbed
radiation is in the ultraviolet region of the spectrum, and thus
invisible, and the emitted light is in the visible region.
Fluorescence has many practical applications, including mineralogy,
gemology, chemical sensors (Fluorescence spectroscopy), fluorescent
labelling, dyes, biological detectors, and, most commonly, fluorescent lamps."
--- On Thu, 6/2/11, Mixon Bill <bmixon...@austin.rr.com> wrote:
From: Mixon Bill <bmixon...@austin.rr.com>
Subject: [Texascavers] fluorescent rope
To: "Cavers Texas" <texascavers@texascavers.com>
Date: Thursday, June 2, 2011, 10:26 PM
Something that can be charged up in light and then will glow for six
hours is phosphorescent, not fluorescent. Sheesh!.--Bill Mixon, fussy editor
Please reply to mmin...@caver.net
Permanent email address is mmin...@illinoisalumni.org
