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2 posts2 participants0 posts today
I missed International Cave Day because I was actually underground instead of on the Internet.
Welcome to the depths of this abandoned quarry, as we explored this timeless corridor, one detail stood out: a chemical formula written directly on the wall.
CaC₂ + 2H₂O → C₂H₂ + Ca(OH)₂
That’s the reaction inside carbide lamps. Calcium carbide reacts with water to produce acetylene gas, which burns with a bright, warm flame. It feels raw and full of character.
Nikon Z6 | 14-24mm | 2,5s | f/8 | ISO 400
Continued thread
Got to do some biosurvey studies on a gorgeous property recently. It is nice to work with landowners who want to share their places, learn about the life and ecosystems they have, and work to properly maintain the ecology. Today they were also planting some native trees not seen around in recent years, and tackling invasive species. Caring for nature is bipartisan; keep fighting for our home, the Earth.
'Feasibility study and optimal #Coal drawing process for fully mechanized #Caving in close-distance extra-thick coal seams' - a #Research article in the Journal of #MineAutomation on #ScienceOpen: https://www.scienceopen.com/document?vid=b73043b1-94ed-4ec2-ba28-2cc3f1af9e8c
ScienceOpenFeasibility study and optimal coal drawing process for fully mechanized caving in close-distance extra-thick coal seams<p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" dir="auto" id="d107733e122">Research on optimal coal drawing parameters for working faces with significant variation
in seam thickness, where the thickness exceeds the standard mining height in close-distance
coal seams, has been limited. This study focused on the feasibility and optimal coal
drawing process for fully mechanized caving in the 011N1
<sup>-1</sup> working face of the Xilutian Coal Mine, Pingzhuang Coal Industry (Group) Co., Ltd.,
Inner Mongolia. First, theoretical analysis determined that the maximum damage depth
of the floor caused by mining in the overlying 021N2 working face was 3.88 m, which
was less than the distance between the 011N1
<sup>-1</sup> and 021N2 working faces. This finding confirmed the feasibility of fully mechanized
caving for the underlying 011N1
<sup>-1</sup> working face. Subsequently, using a combination of theoretical analysis and field
measurements, the study employed a fuzzy mathematics method to quantify the effects
of uniaxial compressive strength, seam burial depth, seam thickness, coal fracture
development, roof grade, and interlayer gangue thickness on the caving characteristics
of the top coal. Membership function evaluation indicated that the top coal caving
tendency of the 011N1
<sup>-1</sup> working face were at a moderate level. Finally, a coal drawing numerical model was
established using the PFC 2D discrete element particle flow software to analyze the
effects of different cutting-to-drawing ratios and coal drawing methods on the recovery
rate of the top coal. The results revealed that, when the seam thickness exceeded
the standard mining height, setting the cutting-to-drawing ratio to 1:4.5 effectively
accommodated thickness variations with minimal impact on top coal recovery. Moreover,
a three-cycle coal drawing process significantly improved the recovery rate. Field
observations demonstrated that, after optimizing the coal drawing process, increasing
the instantaneous cutting-to-drawing ratio with seam thickness better adapted to geological
conditions and significantly enhanced top coal recovery in the working face.
</p><p xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" class="first" dir="auto" id="d107733e137">
<b>摘要</b>：目前针对近距离煤层厚度变化范围较大、煤层厚度超出正常开采高度的工作面的合理放煤工艺参数研 究较少。以内蒙古平庄煤业(集团)有限责任公司西露天煤矿011N1
<sup>-1</sup>工作面为研究对象，开展了近距离特厚煤 层综放开采可行性及合理放煤工艺研究。首先，通过理论分析计算出近距离特厚煤层上方021N2工作面开采后 底板最大破坏深度为3.88
m，小于011N1
<sup>-1</sup>工作面与 021N2 工作面之间的距离，表明对下煤层011N1
<sup>-1</sup>工作面进 行综放开采是可行的。然后，结合理论分析与现场实测，采用模糊数学方法量化了煤体单轴抗压强度、煤层埋深、 煤层厚度、煤体裂隙发育程度、顶板级别及煤层夹矸厚度对顶煤冒放性的影响，基于隶属度函数评定
011N1-
<sup>1</sup>工 作面顶煤冒放性为中等水平。最后，基于 PFC 2D 离散元颗粒流软件建立了放煤数值模型，分析了不同采放比和 放煤方式对顶煤采出率的影响，发现当煤层厚度超过正常开采高度时，将工作面采放比定为
1:4.5 可有效适应煤 层厚度变化，此时对顶煤采出率的影响较小，且采用三轮放煤工艺可有效提高顶煤采出率。现场放煤效果表明， 优化放煤工艺后，随着煤层厚度的增大，增大采放比能够较好地适应地质条件变化，显著提高工作面顶煤采出量。
</p>
For everyone in the world outside the US starting up the isolation process...remember how well that worked in the 1930's. It left tens of millions to die, turning back refugees sent them to their deaths, and fascism still came for their countries anyway. Isolation & abandonment is not a great policy. The world is even more globalized now than it was 100 years ago. The faster we realize we can rise or fall together, the better off everyone will be.
Politics can be complicated, but empathy is not. Empathy demands that we look at what is going on and bear witness. And no one with empathy can then refuse to help. This is why empathy is being made to be the enemy. This is why individualism is being touted.
So. Let's all climb out of this pit now, and together, as the people of the Earth.
I think I am going to get some stickers made. IYKYK. Don't spoil it in comments. Any interest? I'm trying to determine if I need to do a really low volume or if I should just go for 50 or something. I'd ask for $2-$3 which should cover cost + mailing. Vinyl, quality, 3" circle. Pls comment if interested so I have a decent way to get an idea of interest. Thanks!
Keep fighting for the Earth, it is our only home.
Caves are a space highly at risk, and many species in them can be "canaries in the coal mine". The water in them tells the tale of the surface above: pollution, fertilizer, pesticides, microplastics, and more. Too bad wealth doesn't trickle down like pollution into ecosystems. We should really swap those two...
Ce coup ci, on ne devrait pas trop frotter le ciel avec les casques.
#karst #speleo #cave #caving #spelunking #espeleologia #underground #hiking
#karst #speleo #cave #caving #spelunking #espeleologia #underground #hiking
I made a spring!
The torsion spring in my Petzl Stop fatigued recently, and Petzl have stopped making spares. I borrowed from a friend for a while, but finally got round to making a replacement today. Surprisingly easy once I’d made a bit of tooling to hold one end of the spring wire while pulling.
Today went out to an Alabama cave preserve my husband manages and put up some new signs at the parking area then hiked around to look at the cave entrances. One entrance with a waterfall was really nice. There's a 400+ foot pit not too far inside. We ran into some guys who had just rappelled to the bottom and climbed back up. #Caving #Hiking
A year ago this week I was with a team conducting research in the Scărişoara Ice Cave, #romania. This spectacular place contains #ice dating back more than 10,000 years! This unique archive holds valuable information about past #climate variability in this region. Some of the interesting work that has been done in this cave is reported here: https://www.nature.com/articles/s41598-017-01397-w Photo by M. Blatnik. #caves #caving #geology #earthscience #environment
Seems I missed #WomenInSTEM day. Let's support each other, okay? Diversity is our strength.
No big deal, just out here finding new locales and new species all the time...but sure, fuck over our funding. If we don't know they exist we don't have to worry about protecting them, duuuuuh.
(This pseudoscorpion today was quite the surprise! Identification TBD.)
Black Adventure Crew goes caving! Good start for #BlackHistoryMonth - making new memories :)
I approached this group about caving what now feels like a lifetime ago...an outdoor group focused on getting Black and Brown people outside into nature. They were interested in trying it, and now they do trips every year.
While it sucks that DEI is getting canned federally and in some states (why trying to equally include everyone is a bad thing I'll never understand), that doesn't mean we as individuals can't pick up the slack. There are so many stories from folk who say their white friends just never ask them to join for xyz activity...so check yourself. Ask your friends to join you. If you don't have diverse friendships, ask yourself why that is.
Looking forward to presenting about the Ashley Caves Project in Vernal, #Utah next week. #caves #caving #geology #libraries #scienceoutreach
Well since I could use some money now, the whole scientist-without-funding-now thing thanks to stupid executive orders, I got out my prints I have from back when I did art shows and maybe people will...buy some? :) I can sign them if you like. I can also drop ship prints of any of my photography, just DM to ask! It would be nice if I could at least make a couple hundred as my dog had another seizure and I have bills to pay.
To not "spam" ya'll I am going to post each as a reply to this. So, you can just mute this thread if you don't want to see.
Please reply with DM on the photo you'd like to purchase, I can send an invoice to pay. Shipping will be about $10 within the US, $20-$50 for outside the US.
