Search found 1508 matches

by Dennis P Brown
Tue Sep 22, 2020 3:05 pm
Forum: Interesting Links
Topic: 3-D Model of a Stellarator Plasma
Replies: 6
Views: 195

Re: 3-D Model of a Stellarator Plasma

The stellarator design as I have said is never going to provide electric power within orders of magnitude as cheap as fossil fuels assuming it even works. What the W7-X is likely to do is prove that a reactor grade plasma can be heated and held for thirty minutes. Relative to this goal, this propose...
by Dennis P Brown
Mon Sep 21, 2020 3:52 pm
Forum: Interesting Links
Topic: 3-D Model of a Stellarator Plasma
Replies: 6
Views: 195

3-D Model of a Stellarator Plasma

Look's like a successful model used for Tokamak's has been extended to 3-D for stellarators. This model will be used with the Wendelstein 7-X stellarator to test an idea to reduce plasma turbulence by about half. The X-7 will be used to experimentally confirm (or prove otherwise) whether this model ...
by Dennis P Brown
Thu Sep 17, 2020 2:19 pm
Forum: Vacuum Technology (& FAQs)
Topic: IR / Visible ZnSe windows
Replies: 6
Views: 387

Re: IR / Visible ZnSe windows

Wow, looked up the transmission of silicon wafers and it is closer to one micron! While its just 60% over 1.4 microns (high index) it certainly would be a cheap protection plate.
by Dennis P Brown
Thu Sep 17, 2020 1:13 pm
Forum: Announcements and Site Administration Topics
Topic: Coronavirus pandemic
Replies: 177
Views: 32641

Re: Coronavirus pandemic

Again, face masks are our best (and currently, only) defense against Covid even with active spreaders close up and in an enclosed environment; see - https://www.cdc.gov/media/releases/2020/p0714-americans-to-wear-masks.html Anecdotal and unsupported speculation is not worth the risk - masks are prov...
by Dennis P Brown
Wed Sep 16, 2020 10:20 pm
Forum: Vacuum Technology (& FAQs)
Topic: IR / Visible ZnSe windows
Replies: 6
Views: 387

Re: IR / Visible ZnSe windows

Don't know the wavelength your using but if it is above 4 microns, a silicon wafer could be used to protect the ZnS window. Three inch diameter silicon wafers are rather cheap - or use to be; don't know if still avialable but might be worth looking in to if that wavelength is usable.
by Dennis P Brown
Wed Sep 16, 2020 12:43 pm
Forum: Images du Jour
Topic: Caden Burkhardt-Fusor Progress
Replies: 27
Views: 2692

Re: Caden Burkhardt-Fusor Progress

Is your chamber only reaching 100 microns or is that the gauge giving an inaccurate reading? Try the gauge just on the pump head and that will tell you: first, if the gauge is likely accurate; second, whether your chamber is leaking or not.
by Dennis P Brown
Wed Sep 16, 2020 11:27 am
Forum: Vacuum Technology (& FAQs)
Topic: IR / Visible ZnSe windows
Replies: 6
Views: 387

Re: IR / Visible ZnSe windows

Obivously good for the infrared - so I assume that is their purpose? And why so many?
by Dennis P Brown
Mon Sep 14, 2020 6:36 pm
Forum: Items For Sale
Topic: Scientifice Vacuum Item Auction
Replies: 3
Views: 374

Re: Scientifice Vacuum Item Auction

One item (the He leak detector) includes a turbo and auto controller built in. Even if the electrontics don't work for the mass detector, the turbo and controller are worth bidding upon. The lot of stainless steel bellows pipes would be good and I bet are much easier to win in a bid. Do they ship or...
by Dennis P Brown
Mon Sep 14, 2020 6:27 pm
Forum: Interesting Links
Topic: Possible Life in the upper atmosphere of Venus
Replies: 1
Views: 290

Possible Life in the upper atmosphere of Venus

So Phosphine (20 ppb) was found in Venus' atmosphere; there are no known natural processes that create this except life. That does not mean there is life just that until a better process is proposed, or a probe goes there and doesn't find it, then that is the best idea. Of course, I bet NASA and oth...
by Dennis P Brown
Mon Sep 14, 2020 2:05 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Restarting Efforts on Demo Fusor II
Replies: 25
Views: 1831

Re: Restarting Efforts on Demo Fusor II

The key to a useful foreline pipe is that it not collaspe; the vacuum level (as long as plasticizers aren't an issue) capablities are not terribly critical.