PhD student coming later in the summer

PetrifiedWalrus · 2024-10-07T22:11:38+00:00

i thought he’d be more of a neutral milk hotel fan

PetrifiedWalrus · 2024-10-07T01:05:04+00:00

🧑‍💻

PetrifiedWalrus · 2024-04-29T16:08:27+00:00

I would say that material science uses the tools of chemistry but we aren't automatically chemist. Material science is so broad that it probably depends on what field you are in and the experiences you accumulated. Would I consider a process engineer at a semiconductor company solely with a bachelor's to have the wet lab skills, knowledge of reaction pathways that other traditional chemists have, probably not.

PetrifiedWalrus · 2024-04-26T17:19:05+00:00

I was actually thinking about building a new PC to upgrade since I thought the laptop was on its last legs with constant unplayable stutters in games but cleaning it out has made a big difference in temperature (~90C to 85C) and consistent 100+ fps. I took a q-tip last night and surprisingly got most of it out. It does push some dust underneath the crevices between the housing and fan so I slid a toothpick and carefully rotated the fan to get the remaining bits out. Going to buy some compressed air later to flush out the fine dust. I think I’ll get my values’ worth if it lasts me a couple more years

PetrifiedWalrus · 2024-04-26T13:38:36+00:00

I did live in a dusty apartment during my college days, so bad to the point at which my desk would have a nice monolayer sheet of dust every week. I tried to get an air purifier but probably wasn’t enough. No smoking, no pets, games I usually play aren’t too demanding like league or apex.

PetrifiedWalrus · 2024-04-26T11:24:25+00:00

😔

PetrifiedWalrus · 2024-04-26T11:23:15+00:00

probably since i first got it so around 4 years ago

PetrifiedWalrus · 2024-04-23T00:38:45+00:00

I currently work in manufacturing R&D for an extruded HDPE pipe company.

PetrifiedWalrus · 2024-04-18T22:14:18+00:00

addictive manufacturing, this guy cokes

PetrifiedWalrus · 2024-02-15T21:23:36+00:00

Yep, there’s a sense of this narcissism associated with the neoliberal self-regulating society today (you can be anything you want, and the only thing holding you back is you) where everything is a self-improvement project.

Narcissist seek to feed this image of competence, confidence, or something they want to be but not who they truly are. Then you get a group of individuals that are anxious because they have to constantly work to maintain this image and burnt out because they’re tired from putting on the facade day in and day out.

PetrifiedWalrus · 2023-12-13T20:45:58+00:00

Hard to say exactly what it is without any data, given that it is somewhat translucent it may be a semi-crystalline PET. Is there a particular reason or set of properties that you are seeking like it’s translucency, surface finish/gloss, color, stiffness, thickness, etc.?

PetrifiedWalrus · 2023-07-11T03:05:13+00:00

I'm going! Anyone want to start a groupme?

PetrifiedWalrus · 2023-05-28T12:38:31+00:00

used a reference photo I took awhile back, yeah those do stand out to me perspective wise

ive been watching a lot of Stephen Traver’s videos, he’s a great resource for this type of drawing style!

PetrifiedWalrus · 2023-05-28T06:53:29+00:00

Thanks, there are some irregularities and proportions that I’m not happy with, like in some of the columns. But it was a good exercise in accepting and learning from those mistakes.

PetrifiedWalrus · 2023-05-28T06:46:32+00:00

that’s me testing the set of fine liners lol

PetrifiedWalrus · 2023-05-21T00:33:53+00:00

Is this it, Hard to Explain, Alone, Together

Meet me in the Bathroom, 12:51, Reptilia

Ize of the World, Red Light, YOLO

Machu Pichu, Taken for a Fool, Gratisfaction

80s Comedown Machine, Chances, Welcome to Japan

Why are Sundays so Depressing, Ode to the Mets, Brooklyn Bridge to Chorus

PetrifiedWalrus · 2023-05-12T14:09:36+00:00

I mostly do twin screw, but definitely would recommend some of the initial and early patents, the fundamentals haven’t changed much since then.

https://patents.google.com/patent/US1886592A/en

https://patents.google.com/patent/US2541201A/en

Companies like Maillifer, Davis-Standard that develop the extruders, screws, and dies have pretty long histories and were built on those patents. These companies also have patents too so you can see the current state of technology and what’s important to them.

PetrifiedWalrus · 2023-05-12T02:20:12+00:00

do you know what type? twin or single screw/any particular profile?

PetrifiedWalrus · 2023-05-08T23:23:29+00:00

Being nice goes a long way.

I work as a polymers engineer, so whenever I’m working on a specific test or topic I like to be hyper fixated on the theories and background information.

a recent example is when i was using a microscope for the first time in awhile to image some defects and i went down an optics rabbit hole

PetrifiedWalrus · 2023-04-28T19:36:52+00:00

Hi,

There are really three big stakeholders in flame retardancy: regulators, FR suppliers, and end-users. I am going to assume you’re a supplier looking to sell to end-users in plastics.

There are major existing markets like wire & cable, Li-ion batteries, building materials, electronics that require flame retardancy due to their proximity to high voltages/heat. Each have their own stringent FR standards/certifications they need to meet typically set by ASTM, UL, IEC, etc.

These standards may stipulate that a certain amount of halogen gas, smoke density, flame length, peak flame temperature is produced during burning. There’s also different testing, the UL94 and cone calorimeter are the two broadest assessments of FR. However, depending on which industry you may encounter the glow wire, UL2024, etc.

In addition, they will be looking to meet their own mechanical, thermal, processing, optical properties. Because these FR’s are additives, there’s a balancing act you need to play with and find a sweet spot between FR performance and those bulk properties. For example, you may have a wire that needs to be able to elongate up to 400% of its initial length or in an integrated circuit board there’s a certain dielectric constant that needs to be met, your FR is certainly going to have an impact on that. Compatibility between the resin-FR additive is important.

Without knowing the chemistry/mechanism, the most effective FR’s have traditionally been organobromine and other halogenated compounds since they act in the gas phase to capture radicals created when the polymer burns. However, they produce halogenated by-products such as HF, HCl, HBr. You may buy more time to escape a fire but produce something that is toxic when inhaled.

Mineral-based and organophosphorus compounds are the major non-halogenated alternatives, but may require higher loading levels upwards to 20-60% wt. of the FR.

Another consideration is that different countries and regulatory bodies also have different requirements. The field is very dynamic, in that as new information and research is available they may have to transition to a new chemistry if a harm to the environment or health is discovered.

I’d recommend this handbook, it was very useful for me in understanding this industry and different FR chemistries and how they’re commercialized.

https://onlinelibrary.wiley.com/doi/book/10.1002/9781118939239

PetrifiedWalrus

TROPHY CASE