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About druS

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  1. Iceberg to Capetown

    Thermal storage for air-conditioning is not new, it's a little more complex than your scheme but essentially you've covered the basics. There needs to be a method of moderating the temperature of the air being cooled - it may be a more efficient to use very cold air but there are limitations around thermal comfort and people reacting to cold drafts. I haven't seen systems which bring in external ice though there is no reason not to - short of materials handling logistics. Generally the way that commercial systems work is to use cheap electricity in off peak (night time) when there is a lessor requirement for cooling, to produce ice in stead. And then us the ice for cooling during peak (day time). It does help emissions/carbon etc as it reduces peak load and helps flatten power consumption. The generators are more efficient when closer to peak than at low load. Alternatives are storing chilled water and also "phase change" systems - typically CO2/dry ice.
  2. Condensation Help!

    Nitrogen is roughly 80% of air. Changing from air to nitrogen isn't going to have any material impact. As the sole contributor. However if the nitrogen is dry that would solve the problem. So would using dry air. Removing the air also solves the issue. I'd suggest doing the packaging in a very dry environment. BTW why would you take a tablet from a hot truck to a fridge? Oh another way would be to pack the product in a refrigerated environment to start with. When it goes to a hot truck humidity in the residual air get's smaller, and when it is re-refrigerated you are simply back where you were in packaging.
  3. Engineering Degree Questions

    Wartec, I'd look to a bachelor in Science, and a math major. In my course subjects can be chosen in that background within computing. You are likely to have covered mechanics by that point, but if you need the paper look to a post-grad engineering degree with a computing specialist. If you need it. Depends on the university and the courses offered. Look into it.
  4. Help with college pursuits

    Sean Carrol (my favourite physicist who is alive) suggests that only 1 in 4 of his PhD students get a job in theoretical physics. AP I am 56 years old and there is no way I have a likelihood of being one of Sean's 1:4. I'm chasing it anyway, bloke. You, you at 14 asking these questions, hell I'm jealous. Just go for it. In terms of tertiary study, I can only speak from my limited experience. High school fills a background for tertiary study. So compared to the course I am doing right now, if you do Physics at school with advanced math - you'll take about a year (part time) off my bachelor. Then you want to do a bachelor in science (physics). I'd suggest you need work in maths and physics. So a dual major might appeal. Or not. My current study is problematic as I can't fit all my interests into a double major. At the moment my solution is to focus on a math major and get very broad with everything else. I'm not sure it will last. Ultimately you will want post grad (the bachelor is just a start point) and in partical physics it is likely to be a PhD in theoretical physics. Huh! That's a mouthfull of possibilities. In the mean time my advice is to stick, seriously stick, to the stuff that you find interesting. If it is interesting at 14 it will be also at 56, don't fricking loose time. God I'd love to be hitting this right now at 14. Ultimately, just do it.
  5. The Measure Problem

    Before this discussion may be shut down, I just wanted to say just how much I have enjoyed the responses to OP, especially to the "long termers" here. I'm nothing but a novice but increasingly intrigued by math, for once a discussion I could largely follow. Cheers people.
  6. Flood-related engineering...

    Or the building is old and built to old standards. Or they had not worked to best practice modern design. Or the US is behind in building standards. Or they the systems worked which is why emergency teams were there etc etc . Who knows. Having an emergency does not in itself mean a failure of design. The 1:100 benchmarks should be under review pretty much everywhere - a basic tool of adaptation. Though in my experience it tends to happen through Green Building Ratings Systems - such as LEEDS in the US. Legislation and the Standard writers tend to lag the latest thinkers such as adaptation measures in LEEDS (or GreenStar in Australia, or BREAM in the UK). Generally (as I mentioned) this particular issue would be handled through entries to the basements rising to a 1:100 (or other design) level before ramping down. But it won't stop every eventuality. On the whole there have been few experiences like the one under discussion. Not something that is going to suddenly impact building standards around the globe. Where say, something like Grenfell Tower fire in London - certainly impacting local building standards here in Sydney, and I suspect a rolling impact around the world.
  7. Flood-related engineering...

    Building rules on lifts (elevators) differ around the world, I speak from experience in Australia and the UK - not USA. Cell/Mobile reception Lift cars can and are sometimes made of glass. The core that lifts sit inside are mostly made of structural concrete, though sometimes lightweight infill cores are used. Generally it is a matter for efficiency of structural engineering and you would lose an aweful lot of space to sit the lift outside of the shaft. This is sometimes done in lobbies etc where a steel structure is used with glass, and a glass lift car. You can then see through. But that does not necessarily give you mobile/cell reception. External glass curtain walls contribute most of the interference issue to mobile/cell reception in city towers. This is overcome by DAS (Digital Antennae System) systems - essentially a repeater system plugged into cable and distributed through the building. Most Premium grade buildings are briefed to maintain reception in lift cars (granted that from personal experience it is not easy to achieve 100%). But mobile/cell is not an emergency call out system. Lifts are required to have handsets which call back to a central point - generally the lift service provider. AND a stopped lift should be noted back in the control system anyway so that a call out should be alerted. "Airholes"/Lift Shaft ventilation This generally depends on the size of shaft and speed of the lift, but most lift shafts will have vents to reduce pressure build up as the cars move up and down. It isn't really for fresh air for human breathing - there should be enough air in a shaft that this is not a problem anyway. Lift "flood measures" The lift pit will generally have a sump which in normal circumstances should be dry. You would normally expect a float system in that sump that is linked to the building control system. This is primarily for equipment protection, but should also set off alarms in this scenario. I note that far and away the most likely reason behind lift shaft flooding is a burst pipe or some similar internal issue. And this too should have already alerted on the building control systems. External flooding would be something you would expect the building management to step in on. Though if this is "flash" flooding possibly not quick enough. But someone should know what is going on and be calling in assistance. In flood prone areas, design would usually involve unseen barriers at street level to keep extrernal water out on the basements - up to a limit anyway. If there is catastrophic flash flooding you wont keep the water out. As others have said, it isn't common. In general existing building design and should be enough, if implemented reasonably.
  8. We seem to have forgotten about the quoll. I've never sighted one in the bush (not for want of looking in areas they are meant to exist) and wish the researchers all the best in their endeavours.
  9. D Block electron arrangements

    Loving it - plenty for me to cogitate here. Give me a moment or two. Thanks so far hyper
  10. D Block electron arrangements

    Hypervalent_iodine - thanks - i did expect responses that required more thinking on my part! 1. Can we start with why the d-block electron arrangement is 3d in the fourth period. 2. Thence to the specifics with Cr and Cu. In this case the stability issue seems like an observation rather than information behind why it is this way. Full valence electrons create a stable arrangement before we consider the d block. SOmething changes here where all of a sudden there is stability mid-period. 3. The exact cause can get fairly involved. I guess that I want to nudge that issue. Maybe I don't know enough to follow, but at the moment I haven't been able to find anything. Note that I have posited this thread under chemistry - I'm hoping to not end up too deep in quantum. 3. With Fe I need to look at the orbital diagrams or electronic configurations? Does that not take us back to my initial query? Perhaps though this is something that is not what I have learned yet? I'm comfortable with electron configuration up to Argon, and the step through d block doesn't look that hard. But maybe I'm missing something? Cheers Dru
  11. I'm between study periods at the moment and have gone back to something that I noted as interesting during the last study period. Here is a quote: "...the transition metals have the general configuration [Ar]4s23dn except chromium (4s13d5) and copper (4s13d10). The reasons for these exceptions are complex" [Zumdahl et al - Introductory Chemistry: A Foundation] ps I had to edit the super scripts and trust I have it correct. Digging through the various web based tutorials I can work out writing the electron configurations (with cheat notes) but so far nothing to explain why, just "it gets complex". The half shell and complete shell being stable isn't really it either - why is that? OR at least what is the background? Why are the electron configurations for Cu and Cr the way they are? It would be great if I could grasp, or at least be a little clearer, why and when Fe forms the cation iron(II) or iron(III). Let alone what is going on in something like Fe3O4. [I believe a mix of iron(II) and Iron(III) is happening but have no logic behind it.] How does this relate to the concept of noble metals? Why are Cu, Ag and Au noble, but Zn, Cd and Hg not always considered noble?
  12. Confused about resonance structures

    studiot, I doubt I am the only one who wont miss your posts. Plenty goes over my head, but I learn a little bit every time. It is never imo wasted effort.
  13. Scaling up a chemical process

    I am utterly astonished that there was no form of back up cooling. Astonished. Likewise at construction standards in the control room which I would hope would be designed as a safe house under emergency conditions.
  14. beecee This force, I couldn't follow where it is. Between the quarks, or inside the quarks?
  15. humans

    I'm astounded that you haven't seen a funnel web. And I wont run through sharks as it is a thing that perhaps I will cut across more often than people who don't spend much time on the water. Nor how far south irukaji actually travel. In the mean time - can't see how it impacts the human genome, which is where we started.