Category: Uncategorized

Links for November 2022

A Tale of Two Telescopes: WFIRST and Hubble

How much economic growth is necessary to reduce global poverty substantially? by Max Roser
“Adjusted for the purchasing power in each country, 85% of the world population live on less than $30 per day.

Why Does It Take So Long to Count Mail Ballots in Key States? Blame Legislatures: The slow count of mail ballots has been used to cast doubt on election results, but these delays are a deliberate choice by lawmakers in battleground states.

Garage siding replacement

Order:
15? of 4’x8′ SmartSide 38 Series Cedar Texture 8″ OC Panel Engineered Treated Wood Siding
1 of 9’x 100′ Housewrap, $129
staples, have
3 of 2″x4″x8′

JELD-WEN 36 in. x 80 in. 6-Panel Primed Steel Prehung Left-Hand Inswing Front Door w/Brickmould, $270
shims, $2
liquid nails, caulk

DEWALT 2-3/8″ x 0.113″ Ring Shank Galvanized Metal Framing Nails 2000 per Box, $60
Nail gun, rental, DEWALT 20V Framing Nailer, 21-degree, battery

Pavers for water barrel
garden hose nozzle


Finish boards


Terrifying SF stories

A Deepness in the Sky (1999) by Vernor Vinge. The Emergent mindrot virus, a tech of neurotoxins and a device that induces obsession with a single idea or specialty, called Focus, turning people into brilliant appliances.

I Have No Mouth, and I Must Scream” (1967) is a post-apocalyptic science fiction short story by American writer Harlan Ellison. The AI “AM” tortures the last surviving humans.

The Jesus Incident (1979) by Frank Herbert and Bill Ransom. Sequel to is Destination: Void. Ship develops super intelligence, the ability to manipulate space and time, and demands WorShip.

Stand on Zanzibar (1968) and The Sheep Look Up (1972) by John Brunner. Overpopulation and resource depletion have degraded life. Explores all the little ways the breakdown affects the characters and compounds.

Venus of Dreams (1986) and sequels by Pamela Sargent. The world government, a bureaucracy that sees social order as its prime goal, is a bleak but depressingly plausible future. The government suppresses individuality, initiative, and change. Strong resonance with the historic Chinese empire and current Chinese efforts to use technology to control and channel society.

The Space Merchants (1952) by Frederik Pohl and Cyril M. Kornbluth. Also The Merchants’ War (1984). Hyper-consumerism and advertising have destroyed society. Businesses run everything, run the political system as a product line. Through advertising, the public is deluded into thinking that the quality of life is improved by all the products placed on the market. Some products are highly addictive. The most basic elements of life are incredibly scarce, including water and fuel.

Broken Earth series: The Fifth Season (2015), The Obelisk Gate (2016), The Stone Sky (2017) by N.K. Jemisin. The system used to control the orogenes is brutal.

Xenogenesis / Lilith’s Brood series: Dawn (1987), Adulthood Rites (1988), Imago (1989) by Octavia E. Butler. Dystopic series starts with Lilith is held captive by strange aliens and interbreed with an alien of the ‘third sex’.

Classic stories

Make Room! Make Room! (1966) by Harry Harrison.

Can a waterjet be made from a centrifuge?

A waterjet is fast moving water:
waterjet water speed at 40,000 psi = 680 m/s
waterjet water speed at 60,000 psi = 1021 m/s

A pressure washer gives water a speed of 110 m/s.

How fast can a centrifuge spin? Ultracentrifuge speed:
centrifuge spins at 1e5 rpm, has a 10 cm radius rotor.
This give a speed at the rim of:
45 cm rotor circumference at the bottom of the tube
1e5/60 rotations / sec
0.45m/60 x 1e5 = 7.5e2 m/s
So a centrifuge does get water moving fast enough to act as a waterjet.

To turn the rotor spin into a line of water drops, open a door in the bottom of the rotor as the rotor passes a certain point in every spin (1000-2000 times / sec).

If the door is open for 10 us, the rotor will spin 1.5mm.
If the door is open for 1 us, the rotor will spin 0.15 mm.
The water stream will come out in a line, so the resolution in the other dimension can be finer, with the waterjet spread out along the direction of the cut.

A door can’t be mechanically opened and closed that fast, 1 ms is likely the limit.

But a reasonable solution is a rotating (or vibrating) plate with a hole, say spinning 1000/s (or 100/s, opening only every tenth pass), and synchronized with the main rotor spin so opening appeared at the same point along the edge. This would tend to torque the main rotor, but it might be tolerable.

This would give a waterjet with slower cutting–the drop density is 1:1000 or 1:10,000 of a stream.

The rotor would need to be refilled and have enough power to accelerate the new water, and solidly built enough to overcome vibration/torque. And fast centrifuges are expensive.

A micofuge will only give a water speed of 125 m/s.







Thermo Nicolet IR200 Spectrometer

Thermo Nicolet IR200 Spectrometer investigation

Requires a custom power brick, multiple pins. Could not find power specifications. Power bricks do not seem to be available.

Laser was removed from this unit. This is a HeNe laser used “provies the reference signal for triggering data collections and measuring the stroke of the moving mirror.”

Dessicant spot indicates that the dessicant was exhausted. Dessicant appears to be a standard pack. Recharged dessicant in 250F oven for three hours. I’ll try to preserve the optics, I may be able to reuse them.

Requires ENCOMPASS or OMNIC software. I was able to find an OMNIC iso. Untested.

“The interferometer window in your spectrometer is made of KRS-5…” KRS-5 is thallium bromoiodide (TlBr-TlI). KRs-5 (TlBr-TlI) is a gorgeous red crystal commonly used for attenuated total reflection prisms for IR spectroscopy. It is also used as an infrared transmission window in gas and liquid sample cells used with FTIR spectrophotometers in place of Potassium Bromide (KBr) or Cesium Iodide (CsI) for analysis of aqueous samples that would attack KBr or CsI optics. It has a wide transmission range and is virtually insoluble in water. It is a useful alternative to AgCl since it is not photo-sensitive and for ATR applications it will transmit well beyond the 18 micron useful range of ZnSe.

Background on FT-IR:
wikipedia
Nicolet brochure

Unit with case removed:

IR mirror on the left. The right side module looks like a detector:

Back of detector module:

Dry optics compartment:

Dry optics compartment:

Laser diode?:

Corner mirror and flat mirror:

Second corner mirror on solenoid:

Nicolet IR100 and Nicolet IR200 User’s Guide
Nicolet 4700 or Nicolet 6700 User’s Guide
OMNIC User’s Guide, v7.4Transport Kit User’s Guide
Also have “OMNIC- for TIR.iso”
Could not find a service manual.

Beckman DB-G Grating Spectrophotometer teardown

Beckman DB-G Grating Spectrophotometer, Cat NO. 1403.

Links: Grating Spectrophotometer DB GT (1961), University of Queensland Physics Museum

Bulbs:
E 871 (3 leads, HID, for UV)
GE 2331 (visible, 5.9V, 4.66A, 25W)

photomultiplier RCA IP28A, 69-04 (Anode supply: 1250V. Voltage between dynode No9 and anode: 250V. D-C anode current: 2.5ma. Ambient temperature: 75 Deg C. Package: 1-5/16″ D x overall length 3-11/16″ long. Seated height 3-1/8″ long. base: 11 pin plug-in with socket and 30″ cable. Note: Specification sheet available. Maybe replaced with 931A, average anode characteristics are the same.)

Photomultiplier board:
Vacuum tubes:
5654
12BH7A

Main board:
Adams and Westlake Mercury Wetted Contact Relay – MWSL-15093-1B
Vacuum tubes (all filaments lighted):
12BH7a
6973
6EM5
6AX5
85A2/0G3
12AX7

2014 Hugos

Nominations

These look interesting:

Best Novel (1595 nominating ballots)
Ancillary Justice, Ann Leckie (Orbit US/Orbit UK)
Neptune’s Brood, Charles Stross (Ace / Orbit UK)
Parasite, Mira Grant (Orbit US/Orbit UK)

Best Short Story (865 nominating ballots)
“If You Were a Dinosaur, My Love”, Rachel Swirsky (Apex Magazine, Mar-2013)
“The Ink Readers of Doi Saket”, Thomas Olde Heuvelt (Tor.com, 04-2013)
“Selkie Stories Are for Losers”, Sofia Samatar (Strange Horizons, Jan-2013)
“The Water That Falls on You from Nowhere”, John Chu (Tor.com, 02-2013)

Best Related Work (752 nominating ballots)
“We Have Always Fought: Challenging the Women, Cattle and Slaves Narrative”, Kameron Hurley (A Dribble of Ink)

The John W. Campbell Award for Best New Writer
Wesley Chu
Max Gladstone*
Ramez Naam*
Sofia Samatar*
Benjanun Sriduangkaew

Winners

Idea: make a microcentrifuge using RC motors

The motors made for RC planes and cars are high speed and high power.

For example, the Turnigy Trackstar 1/10 12.0T 3300KV Brushless Motor, $23 specs are:
Kv: 3300
Max Voltage: 15v
Max current: 35amps
Watts: 550
Resistance: 0.0221Ohms
Max RPM: 50000

The load on a microfuge will be greater–22 tubes x 1.5 ml can be roughly 44g, figure a 100g total load with the rotor. So slower than max, but still quite fast.

High power ESC modules are sold to run these motors. So they take DC power, and a servo like signal (PWM), +5, GRD.

So a 10k RPM microfuge can be made with one of these motors + ESC, a servo for locking the lid, and a microcontroller to run it, take speed / time settings, and monitor and show the RPMs on a display.

Power could be from a PC power supply or a dedicated supply.