Talk:2514: Lab Equipment

2021-09-14T09:14:21Z

Dhericean: Added Note about Raman Spectroscopy

What kind of lasers are used in mass spectroscopy? [[Special:Contributions/172.70.110.173|172.70.110.173]] 10:58, 11 September 2021 (UTC)
:SFAIK, none. Electron beams can be used, but not sure laser-ablation is a big thing in this subfeld. So I just edited that detail out and added what a plain (i.e. ''light'') spectrometer is. (More likely, this being a laser-lab perhaps making use of novel materials, not a primarily materials-analysis one)
:Any actual Laser Lab-Persons reading this might know otherwise, of course, if they can stop melting things for fun and bother to explain things to us... [[Special:Contributions/162.158.158.88|162.158.158.88]] 18:09, 11 September 2021 (UTC)
: https://en.wikipedia.org/wiki/Matrix-assisted_laser_desorption/ionization#Laser I don't know any other uses for lasers in mass spectroscopy, but MALDI (Matrix-Assisted Laser Desorption Ionization) is commonly used in biochemistry and polymer chemistry (and chemistry of any other fragile macromolecule) to ionize molecules in the sample without breaking (fragmenting) them. It is called a "soft" ionization method due to it's propensity to leave the ions in one piece - something shared with ElectroSpray Ionization (ESI), which is commonly used for same purposes, but doesn't use lasers. [[Special:Contributions/162.158.88.21|162.158.88.21]] 20:15, 11 September 2021 (UTC)
::So, yeah, your link says that lasers are used for ionization (I think of large molecules?) prior to mass spectrometry. The information removal would have been in error. [[Special:Contributions/108.162.219.123|108.162.219.123]] 20:59, 11 September 2021 (UTC) (addendum:unless mass spectrometers don't look like the drawing?)
:::Why are we even assuming "mass spectroscopy" when it's just a "spectrometer" mention, in the context of laser-light research? If it's not the obvious (to me) application, it could be {{w|Spectroscopy#Other_types|one of many other disparate developments}}. [[Special:Contributions/141.101.107.247|141.101.107.247]] 21:52, 11 September 2021 (UTC)
::::Sorry, that was my fault, I was the one who put "mass spectrometer." This is why we have multiple editors.[[Special:Contributions/172.69.22.13|172.69.22.13]] 00:39, 12 September 2021 (UTC)
This could have been my lab in the late 1980's. We used a Nd:YAG laser as a light source for Raman Spectroscopy with a stepper motor controlled diffraction grating spectrometer (I think that was what it was called - was over thirty years ago) controlled via a GPIB (IEEE-488) bus by an Apricot PC running custom APL code (don't ask).
One issue was that as it was an IR beam it had its own black painted room that was closed before a spectrum was run (took I think maybe half an hour). [[User:Dhericean|Dhericean]] ([[User talk:Dhericean|talk]]) 09:14, 14 September 2021 (UTC)

=== Annealing and Tempering ===
Annealing and tempering are used in wider contexts than chocolate and glass, specifically both copper and iron can be annealed and tempered (and most of their alloys). for more information a good place to start is a knife making video where you anneal the knife and then harden just the edge before final sharpening.[[Special:Contributions/108.162.221.191|108.162.221.191]] 18:09, 12 September 2021 (UTC)
:I don't even know where the glass thing came from. I thought a perfectly good link to annealing (definitely including metal, it even says this in the bit I wrote) might be over-explaining what ''might'' be related to chocolate tempering, and then suddenly we're talking about glass which is ''far'' more complicated (just ask Prince Rupert). But that's amorphous solids for you, right..? [[Special:Contributions/141.101.107.115|141.101.107.115]] 23:14, 12 September 2021 (UTC)

::If you have an example of annealing in scientific research then give one, otherwise the phrase "but more likely Randall means a use of annealing in scientific research" sounds like you are speculating about the existence of annealing in scientific research. [[Special:Contributions/172.70.82.111|172.70.82.111]] 01:18, 14 September 2021 (UTC)

=== Cloudflare ===
This is new:
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...popover on the page. Didn't seem to stop me editing/previewing. Is it in response from all the (other) Cloudflare errors we've been getting recently, someone activiting a safety-net? [[Special:Contributions/162.158.158.88|162.158.158.88]] 18:09, 11 September 2021 (UTC)

Talk:2050: 6/6 Time

2018-09-24T18:15:27Z

Dhericean: Added video explanation of Japanese clocks for variable hours

This is actually how time worked in ancient Greece, minus the 6 o'clock part. Sunrise was at 12, sunset at 12 and the length of each hour varied depending on the part of the year [[Special:Contributions/172.68.189.163|172.68.189.163]] 16:15, 24 September 2018 (UTC)

Not just Greece but most of medeaval Europe. The concept of a fixed length hour only arises with clockwork. that Noon, the ninth hour, now occurs at the sixth hour - that we call 12 - is mainly due to post black death labour shortages. {{unsigned|Arachrah}}

: Also ancient Rome. I ''think'' Romans borrowed this system from Greeks and it later spread along with the Roman Empire's influence. [[Special:Contributions/172.68.10.22|172.68.10.22]] 16:52, 24 September 2018 (UTC)

: Before clockwork (as mentioned above) was created, variable hours/minutes/seconds were necessary (at least during daylight hours) as the sundial obviously <sup>({{w|citation needed}})</sup> is just based off of the sun's angle in the sky.[[User:Rajakiit|Raj-a-Kiit]] ([[User talk:Rajakiit|talk]]) 17:42, 24 September 2018 (UTC)

Some facts: {{w|September equinox}} was at 01:54 UTC on September 23 when in the entire US it still was September 22 as can be seen here: [http://aa.usno.navy.mil/seasons?year=2018&tz=-5&dst=1 U.S. Naval Observatory Astronomical Applications Department (Apsides and Seasons 2018)]. This comic was released two days later. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 16:32, 24 September 2018 (UTC)

Could the timing of this comic be related to the [https://www.bbc.com/news/world-europe-45366390 EU voting to end DST within its borders?] [[Special:Contributions/108.162.241.100|108.162.241.100]] 16:51, 24 September 2018 (UTC)
:This isn't about daylight saving time, which just moves clocks forwards and backwards by one hour in most cases. Cueball refers to an equinox when day and night are both 12 hours. --[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 17:05, 24 September 2018 (UTC)

The hours/minutes/seconds get really short/long in the polar regions. {{unsigned ip|162.158.74.243}}

The caption can also be referring to the alteration of time zones for political reasons, such as China having only one now rather than the five it used to use, or the Republic of Kiribati pushing the International Date Line east of its entire territory.[[Special:Contributions/172.69.22.140|172.69.22.140]] 17:50, 24 September 2018 (UTC)

Here is a YouTube video explaining the Japanese system (and how they created mechanical clocks to support it) - [https://youtu.be/3iclecbIgN0?t=135 Begin Japanology - Clocks and Watches]. -- [[User:Dhericean|Dhericean]] ([[User talk:Dhericean|talk]]) 18:15, 24 September 2018 (UTC)

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Talk:2514: Lab Equipment

Talk:2050: 6/6 Time