1

Guest Book / Problems with personal messages.

« on: 09/08/2007 18:23:54 »

I do not know if it is related to our internetconnection, or to our LAN, or if it is a problem that others also have.
When I receive a personal message, there is a warning with the question if I want to open it in a new window.  I click "yes", but it does not open in a new window.  In fact, it does not open at all.
I can not open them by clicking in the message "you have ... messages" either.  What I have to do is start the procedure for sending somenone (anyone) a personal message.  Then I can get in my in-box and in my outbox.
Am I the only one with this problem, or am I forgetting some essential step or what ?

2

General Science / Why do we see things as blue in darkness ?

« on: 05/03/2007 16:40:09 »

I do not know if this is a question of physics or a question of physiology, so I choose "general science"?

The question struck me (again) on occasion of the lunar eclipse a couple of nights ago.  We had a guided walk in the park and adjacent wasteland, with a biologist and an astronomer as guides. 
I remarked that, while all things seem reddish at sunset, they appear blue as the sun is completely down.  I hoped the astronomer would be able to give me an answer, but that was not the case.

Anyway, it must be a well known phenomenon.  Filmmakers used a procedure called "American night" to shoot night scenes in daylight using blue filters on their lenses.

So here is the question :  do we see things in darkness as blue because blue light has more energy than e.g. red light (which would be physics) or because the cones that are receptors for blue are simply more sensitive than those that are receptors for red or those that are receptors for green (which would be physiology) ?  Or is it still something else ?

3

General Science / Alternative motorcar engines

« on: 12/02/2007 19:18:46 »

I have posted the question as a sideline in the topic about diesel fuel and petrol (gasoline), but to no effect.

In the late sixties and/or early seventies the rotary engine (Wankel-engine) was heralded as the engine of the future.  NSU had one model, Mazda had two or three models equipped with them.  There were also two motorbike models :  one by Suzuki (chain driven and axis of the engine transversal) and an other by Hercules (shaft driven, axis of the engine lenghtwise).
NSU became part of the Volkswagen-Audi-Group, and the Ro80 disappeared.  As far as I know, Mazda does not market Wankel-engine driven cars any more. And the motorbikes I mentioned are becoming collector's items.

A simmilar story for the gasturbine.  I remember - it must have been around 1970 - a gasturbine driven racing car at Le Mans, making the full 24 hours.  But it did not appear again.  The only occasions where you can see a moving gasturbine other than in a plane are tractor pulling events.  I suppose the noise is a problem here, an maybe it is difficult to make a gasturbine small enough to fit in a car.

Anyone around who has information about either of this (or both) ?

 

4

Guest Book / Thank you for a great forum.

« on: 05/08/2006 20:21:06 »

In Belgium we had a science show on the radio (Radio 1)(Dutch-speaking part of Belgium) up to a couple of years ago.  It was broadcasted from Monday to Friday, from 9 to 11 a.m.  and treated 2 questions every day.  The public participated by phone, by e-mail and by the forum.  Each afternoon, the questions for next day appeared on the forum, so often there was already a already quite a discussion before actual broadcasting started.
But the questions did not remain on the forum indeffinitely, as in your case.  On occasion, some "members" posted their e-mail adres on the forum in order to continue the discussions by e-mail, using a newsgroup format.
What I do miss here is forums on history or language.
Anyway, I think I'll enjoy it very much, and already posted some replies on subjects where I thought I had something to say.
The show in Belgium was called "Jongens en Wetenschap" (roughly "Boys and Science"), a title borrowed from a series of books from the eraly 1950's.  This was not meant to exclude either the female sex or the elderly, but was indicating that a scientific mind helps to keep you young.
So keep up the good work, and may you be forever young !