21 minutes ago, Sensei said:

The fall of Constantinople took place in 1453.

https://en.wikipedia.org/wiki/Fall_of_Constantinople

 

Sorry typo thanks.

1 hour ago, MigL said:

Rome may have fallen, and sacked numerous times, but the Roman empire assimilated invaders to 'their ways' and flourished, under various guises, well until recent times. Most Germanic empires, up to the Habsbergs of the Austro-Hungarian Empire, fancied themselves as the Holy Roman Empire.
It is no coincidence that Germanic leaders called themselves 'Kaiser' ( even Russian leaders were known as 'Tsars' ), a derivation of Caesar.

See the works of E Gibbon, "The Decline and Fall of the Roman Empire".

Yes but the Holy Roman Emperor was just an honorary title that developed from the coronation of  Charlemagne as emperor by the pope, in return for the protection he provided to Rome against the Lombards etc. Whereas the Roman Empire in the East survived in Constantinople until 1543.   

1 hour ago, Externet said:

Good day.

Is there any found causal or relation between the fall of Rome by the middle of first century and the legalization and rise of christianity ?

The prosper peaceful 'pax romana' era that had abundant reported wealth in many roman citizens...  Where did that people obtained/earned their wealth ?  What business were they involved in those times ?  There were also the not wealthy population; but what activities not tied to government made the rich rich  ?

Yes, can be moved to somewhere else as deserved.  Into politics, history, lounge...

I don't think so. The basic problem, as I understand it, was over-extension of the Empire and consequently increasing reliance of the army on colonised people to man it. I think competition from the Goths, notably Alaric, had something to do with it as well. But that was not until c.4th AD.  I think it was still flourishing in the c.1st. 

On 2/28/2024 at 10:38 PM, swansont said:

“what makes this fee revolutionary is that it will apply to emissions that don’t happen on European soil. The EU already puts a price on many of the emissions created by European firms; now, through the new Carbon Border Adjustment Mechanism, or CBAM, the bloc will charge companies that import the targeted products — cement, aluminum, electricity, fertilizer, hydrogen, iron and steel — into the EU, no matter where in the world those products are made.”

https://knowablemagazine.org/content/article/food-environment/2024/big-boost-europe-carbon-neutral-goals-cbam

This removes incentives to move carbon-intensive industry out of the EU, since that won’t sidestep tariffs any longer. The tariff accounting includes the electricity used for production, so there’s an incentive for business exporting to the EU to use green energy

Sounds good in principle but I can't help wondering how the industries affected are going to calculate the numbers to submit on imported goods, and how the EU will be able to check they are genuine. 

15 hours ago, paulsutton said:

Hi

I am guessing this is the right place to ask this.

I am building a Model of DNA using coloured craft sticks,  which happen to be in 4 colours  Red, Green, Yellow and Blue which is ideal for representing A G C T as the base molecules  Amine, Thymine, Guanine, Cytosine

As I am putting these in pairs, can I have the same molecule connected together? e.g

AA GG CC TT

Looking at the diagram on the compound chemistry

https://www.compoundchem.com/2015/03/24/dna/

I am guessing not,  as this does not show pairs that are the same.

Just asking anyway.

Going Ok so far, I just need some string to tie everything together.   And yes I know I can buy one of these as a kit, but it is fun to do this way but also can help others do the same,  as it is a cheap way of making the model

Thanks

 

Paul

 

No. The pairing is dictated by the way the H bonds line up and this makes only  2 specific pairs fit together, namely A-T and G-C.  This is what ensures that a single strand of DNA, when it has been unzipped, will attract the same sequence of bases as the complementary strand that was unzipped from it, thus making another copy of the previous complementary strand. So your model should have A-T and G-C links only between the strands.

13 minutes ago, StringJunky said:

If an area is repetitively rubbed, as playing an instrument, no lacquer will survive. Look at any well played guitar. It's the price of playing. Does a person want a musical instrument or a museum piece?  You can't have it both ways. The best instruments have the thinnest and most brittle finishes. How long can that last? I've looked into acoustic guitar making for some years and the issues are the same. I've also had one made and insisted on the thinnest finish and bracing. Both are anathema to durability, but are conducive to good tone. Brittleness of the wood and finish determine how clear and resonant the notes are. 

Sure, it makes perfect sense. One wants maximum resonance from the body of the instrument. I would presume the use of drying oils, such as linseed oil, would help repel the moisture from sweat. 

Which reminds me of that joke in the Molesworth books about the boy not paying attention in a biology class about hibernation: 

Master: "Molesworh, what are you doing? Pay attention. Now, what does a bat do in winter?

Molesworth: "Er....er.......It splits if you don't oil it Sir." 

7 minutes ago, Swudu Susuwu said:

All the vaccine does is make you die, you should refuse thus.

The solution is to remove pollution from us.

Global warming causes trillions of dollars of physical damages, and traffic noise worsens spread of COVID (which causes trillions of dollars of healthcare costs,) how long for our leaders to realize the solutions for air traffic is: outlaw, and for land vehicles: subsidizes to switch to fuelless?

Proof that traffic worsens spread of COVID, from our scientist leaders: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8499730/

Proof that COVID causes trillions of dollars of damages: https://healthpolicy.usc.edu/article/covid-19s-total-cost-to-the-economy-in-us-will-reach-14-trillion-by-end-of-2023-new-research/

Proof that global warming causes trillions of dollars of damages: https://climateanalytics.org/publications/carbon-majors-trillion-dollar-damages https://www.nature.com/articles/d41586-022-03573-z

The cost of supercapacitors/ultracapacitors was the purpose that fuelless vehicles had huge prices.
Solar offers abundant power sources for supercapaciters/ultracapaciters.
Scientists now have methods to produce anodes/cathodes from trash (the rest of the capaciter is just carbun, the most abundant of natural resources): https://link.springer.com/chapter/10.1007/978-981-99-9931-6_16
https://www.sciencedirect.com/science/article/abs/pii/S0016236122039497
https://www.nature.com/articles/s41598-017-01319-w

On the contrary, the covid vaccines have saved millions of lives. I have no doubt that air pollution worsens respiratory conditions and will make the symptoms of respiratory diseases worse, or even reduce resistance to infection. However it is mad to suggest that improving air quality is any kind of substitute for vaccines. That really is tinfoil hat territory. 

30 minutes ago, willferral said:

I had not thought of it already being fully polymerised. I thought that was the process of joining the formaldehyde with the urea? Or maybe fully cured is what it is?  Typically when a Urea Formeldhye resin gets catalyzed with an acid it becomes solvent resistant. This Laropal one dissolves in just about anything which is why I like it, I can use ethanol which is fairly low toxicity and it dissolves almost as quick as nitro, but I'm concerned my sweat will burn through it  as 1k topcoats have not been strong enough for my usage which on musical instruments and it gets a lot of wear... I want to mix with shellac based on this recipe I found online https://patents.google.com/patent/US3215655A/en and was hoping to use laropal instead of regular Urea Formelhyde which I'm having a hard time finding and also not need aromatic solvents which give off really strong fumes is a major factor.  

 

I was gonna try sulfuric acid which is used in the making of Laropal, but I would probably be wasting my money buying it, lol

 

Thanks for any help

If you want it for musical instruments I think you maybe ought to consider contacting that Greek outfit and asking. They are in the conservation business, it seems, so pretty close to your sort of application.

But I take your point about sweat when holding an instrument, such as a violin, while performing. You certainly need something that is not weakened or dissolved by sweat. That is a more demanding application than a picture or piece of furniture, certainly.

From looking just now it seems most violin varnishes are traditional, involving things like colophony and linseed oil. There is a lot of stuff about the importance of the varnish not being too rigid or it reduces the sound of the instrument, and issues like that. Well out of my league anyway - I don't play an instrument, only sing. 

1 hour ago, StringJunky said:

AFAIK, from my interest in photography, acidity is the bane of archiving. Acid-free paper and other substrates are used in museum quality work. UV is another one.

That fits, certainly. I suspect this product is the resin already fully polymerised, i.e. the curing step was done during manufacture.  But let's see if the OP comes back and comments.

I would not characterise it as hubris but I am afraid I do think we are witnessing the end of US dominance of geopolitics, as a result of the possibly terminal dysfunction of its politics. One sees every day authoritarians, in Russia, China and even now Israel, becoming ever bolder, as they see the US weaken. The EU is finding itself suddenly exposed by its tacit and complacent reliance on the US to uphold the rules-based order that has largely held sway since the end of the war. The Chinese are gearing up to retake Taiwan and appropriate the South China Sea. Putin knows if he can hold on for a Trump presidency, he will be assured of success in Ukraine and can turn his sights towards the Baltic States and the Kaliningrad exclave. Israel has embarked on a Final Solution to the Gaza problem, via blatant ethnic cleansing and what looks increasingly like genocide, while the US is impotent to stop it. 

There is every sign that the US Republican party has withdrawn support for the democratic system, taking a large chunk of the electorate along with them, and instead embraced a loathsome personality cult. The USA will be lucky if its judicial system, its free media and its term limits on presidents survive. The country will be consumed with its own internal problems for the next few years at least.  Xi, Putin and others will be rubbing their hands at the prospect. 

So much for "making America great again". 

On 2/28/2024 at 7:26 AM, willferral said:

Hi, I have some laropal A81 which I want to use in a varnish. It is a aldehyde resin synthesized from urea, isobutyraldehyde, and formaldehyde.  I'm wondering if I could catalyze it similar how to Urea Formaldehyde is used in varnish and catalyzed commonly with a acid catalyst.  I've tried  BENZENESULFONIC ACID, 4-METHYL in an amount based of what was used in a conversion varnish product based on it's content of solids of Urea Formaldehyde  and it had very little effect possibly making it softer. It certainly didn't cause  a curing other than by evaporation which you would get with a catalyzed varnish . I tried Phosphoric acid at a much higher amount than would typically be used and it resulted in discoloration and much softer finish ..

 

Does anyone know if this type of resin can be catalyzed and if so, with what?  I've tried contacting the manufacturer but they are an industrial supplier and hard to get ahold of.

 

I hope this is an  appropriate question for this forum? As I'm obviously not a chemist, but I thought  I would give it a try, thanks for any help.

This is not my area of expertise either, but looking on line, it seems to be an already cured resin, for dissolving in a solvent as a varnish, or as a component in paint  formulations etc.

I thought this site was interesting: https://www.insituconservation.com/en/products/synthetic_resins/laropal_A81. They seem to recommend it as a varnish for conservation of paintings. I can't imagine they would want to add acid curing agents for such purposes. So my guess would be you just dissolve it in a suitable polar organic solvent, apply it and let the solvent evaporate. But that site, in Greece, has a contact page so you might consider asking them if you need a curing agent or whether you just dissolve it and if so what solvent they recommend.  

3 hours ago, genio said:

I'd like to create a total mg/dL blood cholesterol table that equates to a percentage of total cholesterol in the blood.

100mg/dL total blood cholesterol in % ?

1dL = 100mL

100mg/1000=0.1mL

0.1mL is 0.1% of 100mL ?

0.1% is 100mg/dL of total blood cholesterol ?

Then to saturate the blood at 100% total cholesterol; total blood cholesterol would need to be x in mg/dL.

100/0.1=1000

100mg/dL x 1000 = 100000mg/dL to 100% saturate the blood with total cholesterol ?

Is this correct or is "mL = mg / 1000" incorrect when applied to total cholesterol?

Since there are 10⁶ ml in one litre of water, there are 10⁵ml in one dL.

Equating 1mg with 1ml is only valid for substances with a density of 1g/ml (or 1000kg/m³ in SI units).

So-called  "cholesterol" in blood is not in fact the chemical substance cholesterol, but particles made up of a range of substances including fatty acids, esterified and unesterified cholesterol, proteins etc. From what I can find on the web, these particles have densities ranging from approx 1.05-1.2g/ml. (Blood plasma has a density of 1.006g/ml , apparently.) The chart I found is this one: https://www.nature.com/articles/s41598-021-95451-3/figures/1

Whether these differences in density are significant or not in the context of your enquiry I do not know.  

7 minutes ago, thidmir said:

Sorry I kind of messed up showing the plot, what I meant to show was that there is a strong correlation between CO2 and temperature, so that definitely should be a cause for concern given that a lot of Conservatives have been arguing it may not be worth the cost to deal with climate change. Clearly it is worth a lot, because increasing temperatures by a few more degrees would be very risky, and likely would reflect what happened in the ice ages (sea level rise on the order of 50 - 100 meters given 4 degrees Celsius of temperature increases versus a few inches). My suspicion is that the relatively small amount of sea level rise in the past century was random, and something like this happened also at the beginning of the present ice age 20000 years ago (quadratic sea level rise as shown in the first post, and actually I have reasons to thin that it should actually be cubic) so I wouldn't be too surprised if that's what happened recently. The temperature increase and CO2 increase in the past two centuries since the beginning of the Industrial Revolution  is nonlinear and quadratic, probably due to mass production of fossil burning technologies (in contrast in the ice age the rate of CO2 increase and temperature increase is linear, leading to quadratic increase in sea level). I'm actually publishing a popular science book called Climate Science and Engineering soon with these findings as well as other things. 

I would imagine one difficulty relating the present warming to previous interglacials is the rate of CO2 increase and consequent warming has no parallel in the past. We will be farther from equilibrium as regards melting of ice, isostatic rebound etc. than past warming processes. So any effects that take time to manifest themselves can be expected to lag the warming that causes them.

14 minutes ago, Externet said:

Thanks.  

Surface mounting would take the U straps/brackets, then.  No 'pretty box' as in US at right image.  One in a hundred -or more- US dwellings has masonry walls.

New masonry/european construction foresees piping in walls to use the one at left, and a drain hole.  Found no 'boxes' for additions on masonry.

 

 

Since the pipes and connection will all be behind the appliance, I should have thought there would be little need to worry about the appearance of the piping.  

11 minutes ago, zapatos said:

Where have you found houses made of "paper and sticks"?

Sounds more like Japan.

43 minutes ago, TheVat said:

Surface mounting on concrete or stone is best avoided.  Use an impact drill and masonry screws to attach a couple furring strips,  then run your water lines up those.  If the anchoring degrades you will still have the top of the strips secured to the top plate (assuming this is a basement).  And attaching water pipes like PEX snugly to the wood strips protects them better from pets and small children.  I.e. never have a pipe where it can be easily yanked on, as in the photo shown.

Presumably an operational hazard in the US. 😁

10 minutes ago, Externet said:

Hi. 

In USA, houses made with paper and sticks use flimsy recessed box to connect clotheswasher hoses.  How is it done 'surface-mount' on stone/block/brick walls ?   Looking for such and cannot find in US

I'm in the UK but surely all you need is a couple of U-brackets, like this, isn't it? :-

41 minutes ago, KJW said:

The OP evokes in me a sense of déjà vu. But this was from the other forum, so maybe @exchemist or @geordief could weigh in on this topic.

 

 

I recall similar claims cropping up a number of times. I've always tended to dismiss them as psychological manifestations rather than physical effects, though no doubt they can be real for the sufferer, whatever the cause. 

11 hours ago, Toasted said:

Is it possible to lift lets say a 100 gram kitten using only a singular balloon of a reasonable size - using any methods possible alternatives to helium etc 

(Also for clarification - I am NOT testing on kittens this is purely theoretical haha)

There was a thread on this back in 2005: 

A helium (or hydrogen) balloon can lift of the order of 1g per litre of balloon volume.

1 hour ago, eninn said:

 

 

Allah says (Ye who believe intoxicants and gambling, (dedication of) stones, and (divination by) arrows, are an abomination, of Satan's handiwork: eschew such (abomination), that ye may prosper.

- Satan's plan is (but) to excite enmity and hatred between you, with intoxicants and gambling, and hinder you from the remembrance of God, and from prayer: will ye not then abstain?) 90-91].
Allah
forbade about drinking wine

the Prophet Muhammad, peace be upon him forbade drinking wine
even small amounts , this is confirmed by the verses and hadiths by a thousand and four hundred years

But some doctors were claiming that a little wine can be a cure and heal , and some have claimed that a little of it animates Fouad , what says the latest study on the subject of wine?

In a study conducted by Dr Sarah Lewis of the Department of Social Medicine , University of Bristol found a strong relationship between alcohol intake and between high blood pressure , and said that drinking alcohol affects blood pressure much more than we thought previously. Has conducted a study on a specific segment of people who are suffering from their body 's inability to remove the effects of alcohol after eating . But that does not mean that the damage is limited to these , but every day reveals a new scientists about the damage alcohol .

The number of researchers confirmed that a man , even if eating a small amount of wine it would negatively affect the health and gradually lead to a rise in blood pressure , which causes sudden death of its owner , if not get rid of the final alcohol abuse .

Dr. Sarah says :

This study shows that alcohol consumption may increase blood pressure to a very large border more than we thought and even if a person drinking alcohol in small quantities .

And confirms the researchers that
if a person drinking wine , even a small amount of it and then leave it remain in his body, the amount of alcohol does not disappear only after tens of days, did not specify the researchers exactly how much remains of alcohol in human cells after eating , and there is no accurate studies about it, but Prophet him and told us that the drinker does not accept his prayer God forty days ! ! ! Glory to God ! If the Holy Prophet wants us to be every cell of our body pure , pure ,

research has shown medical conducted on sleep, the brain is issued waves slow during sleep rights and these waves contribute to the production and release of growth hormone is essential for humans , researchers have found something surprising is that a man has eaten amount even if a few molecules of the wine , the wine travels through the blood to the brain and remain for long periods of time and work to confuse the brain is not able to launch electromagnetic waves during sleep and therefore the production of growth hormone depends not able to get to sleep naturally .

researchers comes today to the same speech and with confidence : Even small amount harm to humans and preferably permanently left ! ! ! This is science always comes to bear witness of the truth of this true religion, and that the Prophet Muhammad, peace be upon him when he forbade drinking wine or anything intoxicating

We say to those who abuse to

the Prophet Muhammad, peace be upon him
what the non-Muslims say read, and think about it, if you follow the scientific method of thinking is, get this result ....

You may have heard of the book, wrote a researcher from the West on "The one hundred most influential people in history," The 100: A Ranking of the Most Influential Persons in History, and what I noticed is that this classification itself surprised the author, before anyone else!

This author has to stay away great effort from this classification, made, and in particular, because the image of Islam has been distorted in the West bad, and because it could hurt the book, but he was able to escape this truth that Muhammad "peace and blessings of Allah upon Him was the most influential man "in the history of mankind is!

Michael H. Hart, author of the book says:

Dear readers, they may wonder why I have the name "Mohammed" is placed on the top of the list in this book, but there are compelling arguments that Muhammad is the only man who succeeded on both levels, religious and secular is. The influence of Muhammad's still as strak despite the passage of 14 centuries, and Muhammad is the only political leader who has managed to create a sovereign, who was very religious and scientifically successful, so he deserves the single most influential person in history to be:

It is this unparalleled combination of secular and religious influence which i feel entitles Muhammad to be Considered the most influential single figure in human history.

and say to my brothers and sisters in God be with you ! This prophet worth us to publish his miracle to know the whole world is our prophet and what is our religion? ! Therefore , I ask you to publish the miracles of the Holy Prophet,

 

Dr. Zakir Naik Q&A Alcohol, Medicines permissions in Islam

 

Dr.Zakir Naik - Islam The Solution For Problems of Mankind (Full
 

فتاة بريطانية تسافر مسافة طويلة لتسأل حمزة عن الإسلام في نهاية رائعة
 

اندرو تيت : هذا سبب إسلامي ! رأيت الشيطان | لقاء محمد حجاب

 

 

Is what true or false?

42 minutes ago, HarvianRoid said:

Hi, currently I also do some experiments with NaOH, just looking for info here and found this topic. About a year ago, I also disassembled fireworks, so that silvery stuff in your fireworks that reacts with NaOH is probably an alkali metal, like strontium or lithium or more likely aluminum. These guys are famous for their shiny look, how they react with bases like NaOH, and for making fireworks light up in different colors. The black stuff left behind? That could be an oxide. As for the gas, it might be hydrogen or something with sulfur in it. If you're still not sure, I'd say hit the books or read some online materials like https://edubirdie.com/docs/harvard-university/chem-40-inorganic-chemistry you're never too old to learn, trust me! Just remember to be careful when messing around with chemicals and stick to the safety rules. It is better to be more careful with flammable substances (unfortunately, I know this from my own experience) But I think in general it's a problem to find information about it on the Internet, because fireworks are easily accessible and therefore become a great material for research

Not an alkali metal, as all of these react pretty violently with oxygen in the air. 

5 hours ago, user801028 said:

 

Thanks both. Your information made me see it is probably better to just go for the glass made for the job. I also learned a new thing in thermal expansion. When I was looking at the ads for the stove glass again I suddenly did notice thermal expansion mentioned for one and lauded at "nearly 0%".

0% is interesting. There may I suppose be special "stove glass" with an expansion coefficient even lower than Pyrex. Anyway yes, thermal expansion of a part in the middle of a plate, that is hotter than the periphery, will tend to make it bow up or down, or twist, to relieve the strain  - i.e. warp. One other thing: glass is a good thermal insulator. So the glass top may also protect whatever is underneath from getting too hot. 

Anyway, glad you found the comments helpful and good luck with the repair.

7 hours ago, Chemysrylation said:

What data banks do they use when they mix perfumes and use acids so they know how high they can go in their concentrations?

What data banks do they use when they make prank sprays that smell bad?

Is there anybody here who knows anything about it or who else could I ask?

Grateful for any hints because I am currently clueless. ❔❓

Well I suppose you could get the MSDS for a start. There will generally be information about eye irritation and inhalation on those. But you may have already done that.  

17 minutes ago, Silverstreak said:

I know that there is Einstein's equation that relates energy and matter. However, I was curious about what would occur if there was a universe where light didn't exist. Assuming that's even possible, would there be any relationship between matter and energy or would they be completely separated? Would they fail to exist in such a place? Thank you for indulging my curiosity.

The relationship would still exist, I think, since both energy and mass are properties of matter that do not depend on light. By the way the equation does not relate energy with matter: it relates energy with mass. That distinction is important.

7 minutes ago, Sensei said:

You have AOSP. You can download, install, compile, upload your own OS, and modify it the way you want it to work..

 

Are you living under a rock?

https://www.google.com/search?q=siri+listens+to+everyone

 

Say "Hey, Siri" or "Hello, Google," etc.

If the app is open, the microphone has to listen to everything to detect your words.

You don't have Siri or equivalent, permanently active,  in your TV though, do you? 

Obviously if you have Siri active, you have chosen to have it listen to your voice for commands. What this is about is having an IT system listen to (and send data on) your voice without your consent.

6 minutes ago, StringJunky said:

Some TVs have 5 or more microphones in them, listening for keywords. Ditto other devices.

Do you know that ? I should have though that could be grounds for a lawsuit for invasion of privacy. Can I read about this somewhere? (As it happens, I don't have a TV, but I think it would be scandalous if true.)