Oleg Zabluda's blog
Thursday, April 12, 2018

Stuffed Niffler looking a pictures in a tattoo book
Stuffed Niffler looking a pictures in a tattoo book

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The History of San Francisco Place Names
The History of San Francisco Place Names
An interactive map showing the history of street and landmark names in San Francisco. Use the controls to browse, search, and filter by theme.
http://sfstreets.noahveltman.com/
http://sfstreets.noahveltman.com/

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Enriched uranium - Wikipedia

Let's calculate the minimum amount of energy needed to completely separate U235 from U238.

Consider one mole of natural Uranium (238.03 grams). It's 6.022e23 atoms. When isotopes are completely separated, the entropy is 0. When mixed (0.711% U235, 99.284% U238 by weight), entropy (in nits) is

ΔS = ln(C(6.022e23, 6.022e23*0.00711)) = 2.544e22 nits

entropy in SI:

ΔS = k_B * 2.544e22 nits = 1.380e-23 J/K * 2.544e22 nits = 0.3511 J/K

At room temperature (300 K) the energy to reduce entropy by that much is

ΔE = TΔS = 0.3511 J/K * 300 K = 105 J (i.e. negligible)

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

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Fully ionized hydrogen/Helium seems to emit blackbody radiation
Fully ionized hydrogen/Helium seems to emit blackbody radiation

1.
"""
Temperature Dependence

The key to understanding stellar spectra is that the degree of ionization for various atoms depends strongly on the temperature, as illustrated in the adjacent figure for hydrogen and helium. These plots show the relative abundance of different ionization states of these two atoms as a function of temperature. Thus, hydrogen is present almost entirely in the form of neutral hydrogen (H I) for temperatures below about 7000 K, but above that temperature there is a rapid transition so that above about 10,000 K the hydrogen is present almost completely as ionized hydrogen (H II). In the region 7000 - 10,000 K the gas is a mixture of H I and H II.

Similar considerations hold for helium, but now there are three possibilities. Below about 12,000 K, helium is present primarily as neutral helium (He I). From that temperature up to about 29,000 K, helium is primarily in the first ionized state (He II), and above about 29,000 K most helium is completely ionized (He III).
"""
http://csep10.phys.utk.edu/OJTA2dev/ojta/c2c/ordinary_stars/harvard/ionization_tl.html

2.
"""
Main-sequence stars vary in surface temperature from approximately 2,000 to 50,000 K, [OZ: O-class main sequence stars are >30,000K and they are blackbody]
"""
https://en.wikipedia.org/wiki/Stellar_classification#Harvard_spectral_classification
https://en.wikipedia.org/wiki/Stellar_classification#Harvard_spectral_classification

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Web of Stories | Edward Teller

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П.Л. Капица и Л.Д. Ландау --- ФИЗИЧЕСКИЕ ОСНОВЫ МЕХАНИКИ
П.Л. Капица и Л.Д. Ландау --- ФИЗИЧЕСКИЕ ОСНОВЫ МЕХАНИКИ
"""
Публикуются обработанные тексты лекций по физическим ос- новам механики, прочитанных в 1947 г. академиками П.Л. Капицей и Л.Д. Ландау студентам-первокурсникам Физико–технического фа- культета МГУ [SV: Так начинался физтех]
"""
https://mipt.ru/education/chair/physics/S_I/method/FTF_Meh1.pdf
https://mipt.ru/education/chair/physics/S_I/method/FTF_Meh1.pdf

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"""
"""
From a thermodynamic point of view, a firearm is a special type of piston engine, or in general heat engine where the bullet has a function of a piston. The energy conversion efficiency of a firearm strongly depends on its construction, especially on its caliber and barrel length. However, for illustration, here is the energy balance of a typical small firearm for .300 Hawk ammunition:

Barrel friction 2%
Projectile motion 32%
Hot gases 34%
Barrel heat 30%
Unburned propellant 1%.

which is comparable with a typical piston engine.
"""
https://en.wikipedia.org/wiki/Physics_of_firearms#Firearm_energy_efficiency
https://en.wikipedia.org/wiki/Physics_of_firearms#Firearm_energy_efficiency

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Redwood City elementary school faces closure amid charter growth
Redwood City elementary school faces closure amid charter growth
"""
In June 2014, the Redwood City School District voted unanimously to approve two new charter schools within its boundaries, bringing the total to three. Hundreds of largely immigrant parents had demanded the choice[...] most of its funding comes from the state and is tied to average daily attendance.
[...]
The school board is expected to vote on April 25 to shutter Fair Oaks Elementary School, where enrollment is half of what it was five years ago.
"""
http://kalw.org/post/redwood-city-elementary-school-faces-closure-amid-charter-growth
http://kalw.org/post/redwood-city-elementary-school-faces-closure-amid-charter-growth

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В космос, не отрываясь от земли: космодром Байконур
В космос, не отрываясь от земли: космодром Байконур
"""
четверо авантюристов встречаются в Москве и рассаживаются по машине. Предстоит долгий путь: [...] В программе: посещение цехов с настоящими космическими аппаратами легендарной программы «Энергия-Буран», просмотр запуска ракеты с космонавтами с расстояния почти 2 км, а также море приключений (ну куда же без них!) — и все это: собственными силами, без туров и экскурсий, пропусков и разрешений.
"""
http://www.unexploredworld.ru/blog/1138
http://www.unexploredworld.ru/blog/1138

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Секретная премия Юрия Гагарина
Секретная премия Юрия Гагарина
"""
Снят гриф “секретно” и “сов. секретно” с документов, посвященных истории развития советской космонавтики. Спецкор “МК” изучила вышедший недавно сборник “Советская космическая инициатива в государственных документах 1946—1964 годов”.
"""
http://www.mk.ru/social/article/2010/04/11/466015-sekretnaya-premiya-yuriya-gagarina.html
http://www.mk.ru/social/article/2010/04/11/466015-sekretnaya-premiya-yuriya-gagarina.html

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"""
Hey, a-baby, wake up from your asleep
We have arrived onto the future
And the whole world is become

Elektronik supersonik
Supersonik elektronik

Hey, baby, ride with me away
We doesn't have much time
My blue jeans is tight
So onto my love rocket, climb
Inside tank of fuel is not fuel, but love
Above us, there is nothing above
But the stars, above

All systems gone!
Prepare for downcount!

Five, four, three, one!
Off blast!
"""

Fly away, my space rocket
You no need put money in my pocket
The door is closed, I just lock it
(Ha, ha, ha ha ha)
I put my port plug in your socket

The sonic sky is bright like fire
You and me gets higher and higher
Cut communication wire
Only thing can stop us is flat tire

Ha, ha, ha ha ha ha

For you I will descend the deepest moon crater
I is more stronger than Darth Vapor
Obey me I is your new dictator
For you is Venus, I am Mars
With you I is more richer than all the tzars
Make a wishes on a shooting stars
Then for you I will play on my cosmic guitars!

We has commenced our decent
I trust you enjoy this flight
As much as you enjoy this accent

Now back on Earth its time for downsplash
Into sea of eternal glory my spaceship crash
People have arrived for cheer me from near and far
And as I float, I open door and shout
"I am world's biggest, washed-up superstar!"

(Supersonik elektronik)

As for sure as the sun rises in the west
Of all the singers and poets on Earth I am the bestest
Come, let me put ring of Jupiter on your finger
Then like a smell around you I will forever linger
Okay, is time for end, no more will I sang
Let me take you back in time
I want for you to experience big bang

Long live space race
Long live Molvanîa
"""