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3 hours ago, msfntor said:

Baba Jaga vibes… Creepy street lamp in Wrocław, Poland…

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Baba jaga is the Polish spelling of the same witch/creature folklore (most languages: Baba yaga). Wrocław is a city in Poland, thus baba jaga is perfectly in context…

Treewraith ?

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PS. The pictures above are from strangesounds topic: https://strangesounds.substack.com/p/you-will-know-them-when-they-come

 

Riddle solved: Why was Roman concrete so durable?

An unexpected ancient manufacturing strategy may hold the key to designing concrete that lasts for millennia.

David L. Chandler | MIT News Office - January 6, 2023

MIT-RomanConcrete-01-press_0.jpg?itok=sp

The ancient Romans were masters of engineering, constructing vast networks of roads, aqueducts, ports, and massive buildings, whose remains have survived for two millennia. Many of these structures were built with concrete: Rome’s famed Pantheon, which has the world’s largest unreinforced concrete dome and was dedicated in A.D. 128, is still intact, and some ancient Roman aqueducts still deliver water to Rome today. Meanwhile, many modern concrete structures have crumbled after a few decades.

Researchers have spent decades trying to figure out the secret of this ultradurable ancient construction material, particularly in structures that endured especially harsh conditions, such as docks, sewers, and seawalls, or those constructed in seismically active locations.

Now, a team of investigators from MIT, Harvard University, and laboratories in Italy and Switzerland, has made progress in this field, discovering ancient concrete-manufacturing strategies that incorporated several key self-healing functionalities. The findings are published today in the journal Science Advances, in a paper by MIT professor of civil and environmental engineering Admir Masic, former doctoral student Linda Seymour ’14, PhD ’21, and four others.

For many years, researchers have assumed that the key to the ancient concrete’s durability was based on one ingredient: pozzolanic material such as volcanic ash from the area of Pozzuoli, on the Bay of Naples. This specific kind of ash was even shipped all across the vast Roman empire to be used in construction, and was described as a key ingredient for concrete in accounts by architects and historians at the time.

Under closer examination, these ancient samples also contain small, distinctive, millimeter-scale bright white mineral features, which have been long recognized as a ubiquitous component of Roman concretes. These white chunks, often referred to as “lime clasts,” originate from lime, another key component of the ancient concrete mix. “Ever since I first began working with ancient Roman concrete, I’ve always been fascinated by these features,” says Masic. “These are not found in modern concrete formulations, so why are they present in these ancient materials?”

Previously disregarded as merely evidence of sloppy mixing practices, or poor-quality raw materials, the new study suggests that these tiny lime clasts gave the concrete a previously unrecognized self-healing capability. “The idea that the presence of these lime clasts was simply attributed to low quality control always bothered me,” says Masic. “If the Romans put so much effort into making an outstanding construction material, following all of the detailed recipes that had been optimized over the course of many centuries, why would they put so little effort into ensuring the production of a well-mixed final product? There has to be more to this story.”

Upon further characterization of these lime clasts, using high-resolution multiscale imaging and chemical mapping techniques pioneered in Masic’s research lab, the researchers gained new insights into the potential functionality of these lime clasts.

Historically, it had been assumed that when lime was incorporated into Roman concrete, it was first combined with water to form a highly reactive paste-like material, in a process known as slaking. But this process alone could not account for the presence of the lime clasts. Masic wondered: “Was it possible that the Romans might have actually directly used lime in its more reactive form, known as quicklime?”

Studying samples of this ancient concrete, he and his team determined that the white inclusions were, indeed, made out of various forms of calcium carbonate. And spectroscopic examination provided clues that these had been formed at extreme temperatures, as would be expected from the exothermic reaction produced by using quicklime instead of, or in addition to, the slaked lime in the mixture. Hot mixing, the team has now concluded, was actually the key to the super-durable nature...

MORE: https://news.mit.edu/2023/roman-concrete-durability-lime-casts-0106

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Risk Map from crisis specialist A3M: Which travel countries are the safest

1/9/2023, 11:25:35 AM

 1fed4210-19a0-436b-af25-e89e8b1ca35e_w94  

...and bigger map here: https://www.global-monitoring.com/wp-content/uploads/2022/12/2022-12-06-A3M-Risk-Map-2023.pdf

Wars, unrest and natural disasters have accompanied us in 2022. Has the world become more dangerous for travelers than ten years ago? A new risk map provides answers.

New risk map: has the world become smaller for travellers?

Photo: A3M Global Monitoring

Here: https://newsrnd.com/business/2023-01-09-(s%2B)-risk-map-from-a3m--which-travel-countries-are-the-safest-and-which-are-the-most-dangerous.B1OMc9Y9s.html

Edited by msfntor
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https://www.ksat.com/news/local/2023/01/04/whataburger-bringing-back-dr-pepper-milkshakes-for-limited-time/ Whataburger bringing back Dr Pepper milkshakes for limited time

SAN ANTONIO – Whataburger is bringing joy to Dr Pepper fans this new year — The Dr Pepper Shake is back.

The San Antonio-based burger chain announced that the shakes will return to stores for a limited time.

The popular shakes consist of a vanilla shake base and Dr Pepper syrup.

“Our Dr Pepper Shake is as unique as Dr Pepper itself,” Rich Scheffler, Whataburger’s senior vice president and chief marketing officer, said in a news release. “This shake lets customers experience their favorite soft drink in a new way.”

The price of the shake varies by market.

Edited by legacyfan
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2 hours ago, legacyfan said:

I'm also on Arcolinux Forum now (I'm working on slowly switching over to linux eventually and want all the knowledge I can get) it's my plan to eventually move all my computers to linux

Good luck, but maybe only a few of your computer and (at least) keep a few with windows just for practice. I use Linux but am not on any forum and just do 'live sessions' from the DVD to RAM with limited functions.

Enjoy what you do and do what you enjoy.

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3 hours ago, legacyfan said:

(I'm working on slowly switching over to linux eventually and want all the knowledge I can get) it's my plan to eventually move all my computers to linux

This is a sad moment for me, whenever I see people who were originally using Windows and then migrate to Linux, it makes me feel sad.

I've personally never used Linux or any other OS in my life, only Windows.

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11 minutes ago, mina7601 said:

This is a sad moment for me, whenever I see people who were originally using Windows and then migrate to Linux, it makes me feel sad.

I've personally never used Linux or any other OS in my life, only Windows.

this has been a 3 years in development project (ive done a lot of planning for it before I decided to move) and I plan to stay on here as long as I'm able to 

Edited by legacyfan
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NinaRicci Retweeted

Native Red CloudMaȟpíya Lúta~Hińhan Wakangli @Native3rd

An elder was asked about afterlife: “You say, you don’t believe in heaven or hell?” After some time the elder finally spoke: “I do believe in these places, they surely exist but not at the end of our lives… … We create these places in each day, in each moment!”

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Here: https://twitter.com/Native3rd/status/1612154180994764800

...and Nina Riccihttps://twitter.com/NinaRicci_us

 

 

Edited by msfntor
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