text large_stringlengths 148 17k | id large_stringlengths 47 47 | score float64 2.69 5.31 | tokens int64 36 7.79k | format large_stringclasses 13
values | topic large_stringclasses 2
values | fr_ease float64 20 157 |
|---|---|---|---|---|---|---|
Credit: X-ray: G. Rauw et al., 2003,
Astronomy & Astrophysics, vol. 407, pg. 925; optical: Digitized Sky Survey (STScI, ROE, AAO, UK-PPARC, CalTech, National Geographic Society)
Clustering around a Massive Star
Massive stars have short lives and usually move slowly, so they don't move far from where they're born before... | <urn:uuid:878ad6a9-ebdf-46af-b8f7-dc8b5dc68e8e> | 3.09375 | 420 | Knowledge Article | Science & Tech. | 62.494412 |
This is what scientists are supposed to do, find inconsistencies, point them out, and put them right. And so I gave this a little thought.
A favourite teaser in TV and radio quiz programs is to ask contestants which nation contains the point furthest from the Earth’s centre. Most people think the questioner is referrin... | <urn:uuid:5584a1a7-82d5-45bb-934f-6bedbdfd8e0a> | 3.984375 | 514 | Personal Blog | Science & Tech. | 52.601814 |
strtok, strtok_r - string tokens
Standard C Library (libc, -lc)
strtok(char * restrict str, const char * restrict sep);
strtok_r(char *str, const char *sep, char **lasts);
The strtok() function is used to isolate sequential tokens in a null-terminated
string, str. These tokens are separated in the string by at
least on... | <urn:uuid:b7b87d88-e5cf-4be3-ae64-18e6f99b8799> | 3.1875 | 543 | Documentation | Software Dev. | 61.604161 |
A couple of scientific papers recently (see my Del-icio-us bookmarks) has led to some climate sceptics to point to the fact that sea level may indeed be overstated, a fallacy or perhaps not linked to global climate change.
The first paper by Fletcher and company used various scientific techniques to study the role of c... | <urn:uuid:bec76325-9490-4d84-9f78-35ff572034ee> | 3.46875 | 904 | Personal Blog | Science & Tech. | 45.564958 |
Unscramble the Clouds
Drag the misplaced pieces of the picture to where you think they belong.
What are clouds, anyway?
Clouds are the sky's way of moving water from one place to another.
Water on land or in the ocean evaporates, turning from a liquid to a gas called water vapor. The water vapor rises, cools, and then ... | <urn:uuid:dab05537-0491-41a5-a96a-0b959cb0363f> | 3.625 | 417 | Knowledge Article | Science & Tech. | 62.856997 |
Science Fair Project Encyclopedia
Most vole species have rootless molar teeth which fold in to a series of triangles. Unlike most rodents, voles' molars, as well as their incisors, grow continuously.
They range in size from three to seven inches in length.
Voles live in a variety of environments. The North American mea... | <urn:uuid:17890856-6642-491e-8789-0f92e1a60d04> | 3.890625 | 224 | Knowledge Article | Science & Tech. | 55.070066 |
Looking for Cramster? Cramster is now Chegg Homework Help. Learn More
physics help please?
Three portions of the same liquid are mixed in
acontainer that prevents the exchange of heat with the
environment.Portion A has a mass m and a temperature of
94.0 °C,portion B has a mass m and a temperature of 72.0
°C,and portion... | <urn:uuid:c4817748-d222-4160-ad47-2e06baeaabed> | 3 | 118 | Tutorial | Science & Tech. | 76.877466 |
To the naked eye there is nothing to see, and yet the small transparent container holds something never observed before. For the first time, scientists are studying asteroid dust collected by a spacecraft and returned to Earth. Ute Böttger, from the Institute of Planetary Research at the German Aerospace Center (Deutsc... | <urn:uuid:6a96a637-e046-4012-a4bb-6430940aeea2> | 3.03125 | 141 | Truncated | Science & Tech. | 44.849075 |
Mapping the Milky Way Galaxy with LISA
Student: Jose A. McKinnon
University of Texas at Brownsville
Degree Level: Master of Science
Internship Site: NASA Goddard Space Flight Center, Greenbelt, Maryland
Mentors: Dr. John Baker and Dr. Jeffrey Livas
Abstract: Gravitational wave detectors in the mHz band (such as the Las... | <urn:uuid:aaffe57d-597c-4b78-a844-443414cf8e38> | 2.90625 | 271 | Academic Writing | Science & Tech. | 28.647884 |
Actinopterygii (ray-finned fishes) > Perciformes
(Perch-likes) > Cichlidae
(Cichlids) > Pseudocrenilabrinae
Etymology: Lamprologus: Greek, lampros = light + Greek, lagos = hare (Ref. 45335).
Environment / Climate / Range
Freshwater; benthopelagic; pH range: 7.4 - 8.4; dH range: 7 - 30; depth range 3 - 60 m, usually 5 -... | <urn:uuid:0d6f152e-b88f-4c07-940a-009174547994> | 3.015625 | 542 | Knowledge Article | Science & Tech. | 63.090397 |
Where Are the Oldest Rocks on Earth Found?
The oldest rocks in the grand canyon are about 2 billion years old, but they are not even half the age of the oldest known rocks on earth.
CREDIT: The National Park Service
You don't need to go to a museum to find really, really old things. Ordinary rocks, for example, may be ... | <urn:uuid:83bbfdf0-b2e8-4e31-a00f-2aeddd69a72d> | 3.84375 | 516 | Listicle | Science & Tech. | 58.554311 |
Search our database of handpicked sites
Looking for a great physics site? We've tracked down the very best and checked them for accuracy. Just fill out the fields below and we'll do the rest.
You searched for
We found 14 results on physics.org and 106 results in our database of sites
105 are Websites,
1 is a Videos,
an... | <urn:uuid:91066a07-4df6-4f42-90d8-5d0f9705ed29> | 2.796875 | 303 | Content Listing | Science & Tech. | 64.59645 |
It might seem intuitively obvious that a layer of dense liquid resting on a less dense liquid is an unstable situation. But what isn't so obvious is the complex way that liquids arranged in this manner tend to move. The Rayleigh-Taylor Instability is a phenomenon that leads to beautiful, and mathematically intricate, s... | <urn:uuid:d5b32e97-50ce-46aa-8907-a58e43e072d5> | 4.125 | 385 | Knowledge Article | Science & Tech. | 33.316389 |
In the applet below, the masses of the small bodies are not all equal. Therefore, they are not evenly spaced around the central body. The smaller bodies (shown in blue) tend to be clumped together whereas the more massive bodies (shown in white) are spaced out. The mass per unit distance is approximately constant (alth... | <urn:uuid:54914504-e209-43c0-9153-69d8dde376bb> | 3.578125 | 121 | Knowledge Article | Science & Tech. | 53.591 |
Apr 19 2012
Last Friday I took the day off and visited Presque Isle State Park. It felt like a mini beach vacation to walk along the shore of Lake Erie and pretend I was at the ocean.
With the waves lapping at my feet I paused to gaze north. I knew that Long Point, Canada was more than 25 miles away but it was beyond t... | <urn:uuid:2764ffbc-32de-421a-884a-f7a07c1d8a71> | 3 | 442 | Personal Blog | Science & Tech. | 65.530435 |
If I see another fruit tree, I’ll throw up!
I guess that most people have seen information about the eco-footprint of different foods. It takes so many litres of water to produce a kilo of this or that food. Or figures about how much energy is consumed in the production of meat, coffee, chocolate or rice. But there are... | <urn:uuid:e0cf5340-bce1-4d6a-9aa0-897735e857c7> | 2.75 | 2,820 | Personal Blog | Science & Tech. | 54.138699 |
Generation IV reactor
Generation IV reactors (Gen IV) are a set of theoretical nuclear reactor designs currently being researched. Most of these designs are generally not expected to be available for commercial construction before 2030. Current reactors in operation around the world are generally considered second- or ... | <urn:uuid:99c8a252-e80b-4bf0-b05d-99358a2ac87a> | 3.609375 | 2,299 | Knowledge Article | Science & Tech. | 34.634658 |
At Geneva International Airport, SRB Energy delivered the first of the solar panels that will form one of the largest solar energy systems of Switzerland. Ultimately, some 300 high-temperature solar thermal panels will cover a surface of 1200 square metres on the roof of the airports main terminal building. The panels,... | <urn:uuid:9e9e687b-9e58-419f-9304-5f58c18dd929> | 2.90625 | 214 | Content Listing | Science & Tech. | 25.16886 |
In the November 21 Proceedings of the National Academy of Sciences, Peterson et al. describe a screen for chemicals that can be used to interfere with, and time, developmental events in zebrafish (Proc Natl Acad Sci USA 2000, 97:12965-12969). Zebrafish eggs were arrayed three to a well in 96-well plates, along with one... | <urn:uuid:4c1da66c-f995-4989-87d5-80791f0c85ec> | 2.96875 | 234 | Truncated | Science & Tech. | 27.2825 |
A SoftReference is a reference that the garbage collector can decide to clear if it is the only reference left to an object, and the GC decides (through some undefined process) that there is enough memory pressure to warrant clearing it. SoftReferences are generally used to implement memory-sensitive caches. A mistake ... | <urn:uuid:3e3badfe-fb24-4db7-a17a-e5acddfcd562> | 2.734375 | 825 | Q&A Forum | Software Dev. | 53.029705 |
Asynchronous programming (Windows Store apps)
Using asynchronous programming helps your apps stay responsive when they do work that might take an extended amount of time. For example, an app that downloads information from the Internet might spend several seconds waiting for the information to arrive. If you use a sync... | <urn:uuid:fee17d2d-432b-4cab-97af-190d7d1b775b> | 3.171875 | 705 | Documentation | Software Dev. | 29.736711 |
A team led by Lawrence Berkeley National Laboratory (Berkeley Lab) scientists hopes to become the first in the world to produce electricity from the Earth’s heat using CO2. They also want to permanently store some of the CO2 underground, where it can’t contribute to climate change.
About a year from now, two nondescrip... | <urn:uuid:4c0294c3-61c3-4206-8224-aedd637e59f4> | 4.1875 | 459 | Truncated | Science & Tech. | 44.476935 |
Copyright © University of Cambridge. All rights reserved.
'Curved Square' printed from http://nrich.maths.org/
A square of side length 1 has an arc of radius 1 drawn from each of its corners, as in the following diagram. The arcs intersect inside the square at four points, to create the shaded region.
What is the area ... | <urn:uuid:7dc7c2be-9262-4faa-8fd6-4e6e89a30de3> | 3.234375 | 151 | Tutorial | Science & Tech. | 68.954135 |
I mean, in the sense that the act of closing curtains would somehow reduce the amount of heat loss of the house to the outside, thus making it warmer for a given supply of heating.
If the inside surface of the window is colder than the air in your room then the room will lose heat to the window. If this is the case the... | <urn:uuid:dce9382f-ee5c-47f7-9a90-2cf087ca4c38> | 2.8125 | 468 | Q&A Forum | Science & Tech. | 55.633617 |
← Geology Midterm Test
5 Written Questions
5 Matching Questions
- 4.5 billion years old
- a A piece of the Earth's crust fragmented by convective motion in the Earth's interior
- b What is Earth's Age
- c What is the layer of rock that forms a thin skin over Earth's surface.
- d The outer layer of the Earth is called
-... | <urn:uuid:e0ffbacb-cc6f-46e4-a7bd-3e2c67ccc042> | 3.9375 | 283 | Q&A Forum | Science & Tech. | 43.718797 |
After you declare a name for some data, the next thing is usually to do some operation with the data. Microsoft classifies all Visual Basic operators as:
- Arithmetic Operators
- Comparison Operators
- Concatenation Operators
Arithmetic operations include the familiar "+", "*", and "/" but also including interesting va... | <urn:uuid:75496f5d-949e-4f6f-b66c-d9f1583bc78e> | 4.3125 | 576 | Documentation | Software Dev. | 52.8655 |
Hardiness zone warming calculator
The current USDA Plant Hardiness Zone Map is based on average yearly minimum temperatures over 1976-2005 and therefore doesn't fully include recent warming. This calculator estimates the amount by which the average yearly minimum temperature has warmed over points in the coterminous Un... | <urn:uuid:111cef89-6fbf-44ba-89c5-2f8e9015d691> | 3 | 192 | Documentation | Science & Tech. | 42.619757 |
Natron is a white, crystalline hygroscopic mineral salt, primarily a mixture of sodium bicarbonate (common baking soda) and sodium carbonate (soda ash) with small amounts of sodium chloride (table salt) and sodium sulfate. Natron is somewhat antiseptic and is also an exfoliant and a desiccant. In ancient Egypt Natron w... | <urn:uuid:ec4c3c46-2df8-4bd6-ba7b-e90fb3f5e5bb> | 3.109375 | 166 | Knowledge Article | Science & Tech. | 33.55 |
Preparing a Form for Digital Signatures
HTML forms are standard HTML files that contain one pair of <FORM> and </FORM> labels within the body section. In between the form labels one can find several object definitions such as text fields, radio buttons, pull-down menus, and the like. These objects are created with spec... | <urn:uuid:207005c5-d440-47de-a78a-4183f2271a90> | 3.40625 | 932 | Documentation | Software Dev. | 50.107197 |
Buses and Observers
The other code of interest is the Event Bus and Observer classes previously mentioned. The Event Bus class lets you marshal observers for a given event. These are not browser-based events but code-based ones. You can create as many as you want and your observers will contain the code necessary to pr... | <urn:uuid:072ab80c-c151-4265-a5ad-28ca55b996c0> | 2.796875 | 577 | Documentation | Software Dev. | 45.366501 |
Environmental Science: How to Find Fresh Water
To effectively use freshwater resources, people must find ways to control the water flowing on the Earth’s surface or access the groundwater below. There are various ways to access the Earth’s fresh water.
Through the hydrologic cycle, water constantly moves among the ocea... | <urn:uuid:00487b13-3758-4a29-8265-e200c63b13df> | 3.875 | 566 | Tutorial | Science & Tech. | 43.379735 |
First page Back Continue Last page Overview Graphics
Convenient linked-list facility in <linux/list.h>
- Used in thousands of places in the kernel
Add a struct list_head member to the structure whose instances will be part of the linked list. It is usually named node when each instance needs to only be part of a single... | <urn:uuid:025a7e70-eafc-4af2-8573-334d050d0af4> | 3.125 | 197 | Documentation | Software Dev. | 26.925 |
NASA's twin Mars rovers continue to turn up intriguing new rock formations after a combined total of nearly 1120 Martian days on the planet.
After discovering relatively little, other than basaltic lava flows, during its first six months on the Red Planet, Spirit continues to make up for lost time as it ascends Husband... | <urn:uuid:af6ff28f-561d-4559-896e-1d51cd166a56> | 2.71875 | 1,049 | Truncated | Science & Tech. | 48.340821 |
Earth wasn't always the only water-world in the solar system. Mars and Venus also appear to have started out wet but, as conditions changed, they lost their oceans. So how has Earth managed to avoid a similar fate?
Our planet's climate is remarkably stable, and has remained in a narrow, liveable, range for almost 4 bil... | <urn:uuid:e8265d86-89b0-4b2e-8f3a-69162db16cb9> | 4.03125 | 186 | Truncated | Science & Tech. | 54.546766 |
Yes - the emisivity of screen within the wavelength concerned certainly has major impact. The is why we wrap our buildings in foil to reflect some of the infra-red radiation and apply low-e coatings to glass to assist with heat loss/gain. Cardboard = no chance (virtually) metal = high chance of reflecting......microwav... | <urn:uuid:b6960a93-ab76-4c3a-b5fc-ce2aac8ce486> | 2.8125 | 214 | Comment Section | Science & Tech. | 62.73928 |
These two peaks are relatively inactiveit's the double crater between them, Tompaluan, that keeps residents on their toes. Since the mid-19th century, Tompaluan has exploded in phreatic eruptions that are a mix of steam, water, ash, rock, and " volcanic bombs,"hunks of molten rock that cool before landing. Tompaluan al... | <urn:uuid:362110b4-3adb-487b-b0ba-2f7c1aebd211> | 2.921875 | 159 | Listicle | Science & Tech. | 45.699385 |
Space Debris Update
Though numbers vary, it is estimated that there are at least 8,000 trackable objects in near-Earth space. These objects are baseball size or larger and can be tracked by ground-based radars. Of these 8,000 items, only 400-500 are operational spacecraft. The rest is space junk! This space junk or orb... | <urn:uuid:4bd1d92e-a2ff-41ee-a191-4b6de7399d36> | 3.765625 | 667 | Knowledge Article | Science & Tech. | 48.316115 |
NMR & IR Tables
These pages provide data that will help you make crude interpretations of NMR chemical shifts and IR vibration frequencies.
Much better tables can be found in the library books on reserve (see Reserve Materials). The reserve books also provide information about other spectral data, such as NMR coupling ... | <urn:uuid:9cbbe97c-8a0d-49bd-8a55-7490c3b828b1> | 2.828125 | 1,375 | Documentation | Science & Tech. | 55.993215 |
by Gregory McNamee
Birds are better known for their sense of sight than for their sense of smell. That does them a disservice, scientists Darla Zelinetsky and her research colleagues hold, writing in a newly published paper on avian olfaction that birds owe their sense of smell to their theropod dinosaurian ancestors, ... | <urn:uuid:b5b78465-492e-4b14-92ea-0799e6740f18> | 3.328125 | 410 | Truncated | Science & Tech. | 33.930478 |
Haskell has a powerful concurrency library which is surprisingly easy to use. The Control.Concurrent library is shipped with the standard installation of ghc and provides everything needed to get started.
As a small test I want to write a programme which reads numbers from stdin, spawns a new process to calculate the F... | <urn:uuid:a5c75e67-4b16-43a8-8751-ebed9bdfbab0> | 2.734375 | 496 | Documentation | Software Dev. | 62.268826 |
In addition to using data manipulation statements directly, as just described, it is also possible to manipulate table data by invoking a procedure. Procedures perform the specific data manipulations laid out in the procedure definition.
Any SQL statement in the grouping procedural-sql-statement, see the Mimer SQL Refe... | <urn:uuid:da8c4482-222a-49b0-bbfb-1f66f7ae7ea0> | 2.96875 | 372 | Documentation | Software Dev. | 20.092143 |
Show: Delphi C++
Developing a Windows Application
From RAD Studio
Go Up to How To Build VCL Forms Applications
The following procedure illustrates the essential steps for building a Windows application.
To create a Windows project
- Select File > New > VCL Forms Application - Delphi. The Windows Designer displays.
- If... | <urn:uuid:9311df96-c468-4647-a9ea-1d82907e8fbf> | 2.828125 | 164 | Tutorial | Software Dev. | 42.86478 |
Family: Lycaenidae, Gossamer-wing Butterflies view all from this family
Description The Atala, Eumaeus atala, is a small colorful butterfly in the family Lycaenidae. It is found in southeastern Florida, the Bahamas, and Cuba. Its coloration and habits are unique among butterflies within its range.
In Florida, the cater... | <urn:uuid:ea01487e-7eee-4c24-9d26-bda2e77480f3> | 3.03125 | 541 | Knowledge Article | Science & Tech. | 42.313702 |
10 Points about Java heap memory
When I started java programming I didn't know what is java heap or heap space in Java, I was even not aware of where does object in Java gets created, it’s when I started doing professional programming I came across error java.lang.OutOfMemoryError in Tomcat then I realized What is Heap... | <urn:uuid:707d7e52-c0cf-4df1-b165-b6c080e97309> | 3.046875 | 2,031 | Personal Blog | Software Dev. | 51.320865 |
What Are Invasive Species?
There are many threats to biodiversity including invasive species. They are species of living things (plants, animals, and microorganisms) that are brought into an area, so they are not native to that ecosystem. Sometimes they can harm the ecosystem by quickly spreading and threatening the bi... | <urn:uuid:bde66ac4-1372-471f-b712-a201a2860653> | 3.46875 | 955 | Knowledge Article | Science & Tech. | 52.018031 |
Sodium Polycarbonate and Salt Water
Date: Fall 2011
Why is it hard for salt water to adsorb into sodium polycarbonate?
Well, you have got me there! I had never heard of "sodium
polycarbonate", and after a thorough search, I was unable to find any
mention of it anywhere.
"Polycarbonate" is the generic name for a type of... | <urn:uuid:ac29926a-b7a3-46ff-a728-432cacb08de5> | 2.875 | 202 | Q&A Forum | Science & Tech. | 42.564602 |
Fall, S., A. Watts, J. Nielsen-Gammon, E. Jones, D. Niyogi, J. Christy, and R.A. Pielke Sr., 2011: Analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends. J. Geophys. Res., in press. Copyright (2011) American Geophysical Union.
has been accepted and is... | <urn:uuid:4abbf3aa-e720-4729-a5e4-e52e465ec428> | 2.75 | 2,289 | Academic Writing | Science & Tech. | 36.975645 |
An anonymous reader writes "NASA has just revealed a new, super-black material, claiming it is the most light absorbent material ever developed, and capable of absorbing 99% of ultraviolet, infrared, far-infrared, and visible light. The super-black material is about 10,000 times thinner than a human hair and created us... | <urn:uuid:2243c72d-d168-49c3-8389-da8486a6e612> | 3.25 | 237 | Comment Section | Science & Tech. | 31.659898 |
Thirsty for Answers: Preparing for the Water-related Impacts of Climate Change in American Cities
In this report the Natural Resources Defense Council (NRDC) has compiled local and regional research findings about the water-related impacts of climate change in 12 U.S. cities. NRDC examined more than 75 scientific studi... | <urn:uuid:2180047a-9a0b-463e-a5ad-6f54182b2a34> | 2.9375 | 239 | Knowledge Article | Science & Tech. | 35.715263 |
Using this graphic and referring to it is encouraged, and please use it in presentations, web pages, newspapers, blogs and reports.
For any form of publication, please include the link to this page and give the cartographer/designer credit (in this case Hugo Ahlenius, UNEP/GRID-Arendal)
Circumpolar Arctic Vegetation Ma... | <urn:uuid:fab23554-6ae2-4698-a304-6c4e8daade3a> | 3.5625 | 233 | Knowledge Article | Science & Tech. | 34.818333 |
In addition to the considerations of liquid hydrogen for rockets by Tsiolkovskiy, Goddard, and Oberth, other concurrent activities contributed to hydrogen technology. The largest and best known of these were the development and operation of the large dirigibles in Germany, Italy, Great Britain, and the United States fr... | <urn:uuid:be951017-e5f4-48d3-a245-8242fbbdcdad> | 3.703125 | 3,417 | Knowledge Article | Science & Tech. | 38.676513 |
Mari cure was given loads of plutonium by the poland government and her research on this element lead to the discovery and radium where one night in one of her store room an abandoned box and plutonium was glowing and that led to the invention of radium.
Abhijeet Banerjee said:
(Wed, Jan 12, 2011 05:37:37 AM)
Marie cur... | <urn:uuid:51401901-edab-49b2-9dad-4abe1650a4fb> | 3.390625 | 1,220 | Comment Section | Science & Tech. | 70.164749 |
The Alchemy web site on Levity.com
(ascribed to Trithemius)
Hearupon follows a modern chemical experiment.
Interpretation and testing done by Sam Van Oort, assistance from Adam McLean
Note: if you have laboratory grade sulfur, you can probably skip to step 8 and use it in place of prepared sulfur.
alum (potassium alumi... | <urn:uuid:fd6d6d7b-b9d7-4022-9c7f-0beb1756afea> | 3.109375 | 2,561 | Tutorial | Science & Tech. | 56.868769 |
Save your breath asteroid worriers
2005 YU55 will not strike the Earth or Moon, and if you are lucky at 9:00 PM Eastern time, you might see it streak across the sky just above the horizon. Sorry to disappoint the doomsayers; you will still have to pay your mortgages.
“Near-Earth asteroid 2005 YU55 will pass within 0.85... | <urn:uuid:c3e551a1-9845-4a40-91df-098d757c415e> | 2.8125 | 532 | Comment Section | Science & Tech. | 43.250661 |
wallyg/Flickr Creative Commons License
Generally, wine and fish can be paired quite nicely. In California wine country, however, the relationship between the two has not been so harmonious. New research has found a correlation between markedly higher death rates in steelhead trout with lowered summer water levels and t... | <urn:uuid:66acb208-355d-40e9-863b-71c1aaded609> | 2.8125 | 531 | Content Listing | Science & Tech. | 44.807541 |
> to me that these algae have the same DNA sequence as modern forms.
Foul. You know I can't do that. Prove to me that they are different.
> >There's room enough on the table for more than one theory. As a
> >professional geologist, I agree with Moorad; physics is testable,
> >historical geology is guessable.
> Lets sta... | <urn:uuid:3c04c562-ecd4-45ca-bfe7-9fa8462b79ec> | 3.0625 | 286 | Comment Section | Science & Tech. | 54.30187 |
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2006 March 9
Explanation: This popular group is famous as the Leo Triplet - a gathering of three magnificent galaxies in one field of view. Crowd pl... | <urn:uuid:e8d9966a-680b-4b1e-9497-85497b2753c2> | 3.21875 | 297 | Knowledge Article | Science & Tech. | 54.4105 |
By Chris Steinkamp
Last year was the warmest in recorded history. But now we’re experiencing a sudden shift from the unseasonably warm temperatures of 2012 to below-freezing temperatures as we begin the new year.
We all know that what’s happening out the window is weather, not climate, but these radical shifts in tempe... | <urn:uuid:c33284fb-c447-434c-a865-8968a5b86056> | 3.25 | 1,017 | Personal Blog | Science & Tech. | 38.480884 |
In the constellation Norma
10 to 15 times the mass of the Sun
Diameter roughly 35-55 miles (60-90 km)
In the quarter-century that orbiting X-ray telescopes had been watching the sky, a distant star system in the southern constellation Norma had never made a peep. But in 1998, that changed. On September 7, the Rossi X-R... | <urn:uuid:8b0f5ff0-f7f3-4f48-a204-4466537362b8> | 3.796875 | 728 | Knowledge Article | Science & Tech. | 62.925069 |
26 November 2012
We had a nice display of gravity waves over the Mid Atlantic on Saturday. You have likely seen this type of cloud pattern in the sky many times and the view from the Aqua satellite as it passed over Virginia on Saturday shows it well. In many waves this is the atmospheric equivalent of throwing a rock ... | <urn:uuid:63639756-cbed-412a-91ed-34345ee2fabf> | 3.21875 | 242 | Personal Blog | Science & Tech. | 60.207619 |
The Great Red Spot is a great anti-cyclonic (high pressure) storm akin to a hurricane on Earth, but it is enormous (three Earths would fit within its boundaries) and it has persisted for at least the 400 years that humans have observed it through telescopes. Since it is anti-cyclonic in Jupiter's Southern hemisphere, t... | <urn:uuid:a13ef10b-9024-4c0b-80fc-68922ae6705a> | 4.03125 | 411 | Academic Writing | Science & Tech. | 40.687057 |
Series Reactions in a CSTR with Time-Varying Input
Consider the following series reaction taking place in a CSTR (continuous stirred-tank reactor): . No chemical species (, , or ) are initially present in the reactor. The reactor is fed with only species at the time-varying feed rate .
The governing equations, obtained... | <urn:uuid:24109c70-eedf-4274-86cb-c2c6fa06a1d7> | 3.09375 | 139 | Tutorial | Science & Tech. | 40.542045 |
This experiment is intended to measure the effect of chemicals used in alternative fuels on plant germination. Students will learn about toxicity and its quantification, LD50 values. To test the toxicity, students will put seeds into petri dishes with filter paper soaked with the biofuel of interest. In the second lab ... | <urn:uuid:73497d74-cdd1-4644-b1d1-d83e4edb2e90> | 3.046875 | 253 | Knowledge Article | Science & Tech. | 31.811074 |
Driver Installation Ubuntu kernel 2.6.17 Basic Help
bryan at kadzban.is-a-geek.net
Thu Apr 5 12:45:52 EDT 2007
On Thu, Apr 05, 2007 at 09:43:47AM -0400, Bob Beers wrote:
> (I think bash has deprecated that usage in favor of "$()", but I don't know
> which way is more portable across different shells.)
Backticks are def... | <urn:uuid:83c50fdd-34a8-4d04-831b-5aea0d7458b5> | 2.6875 | 597 | Comment Section | Software Dev. | 75.89985 |
Tonight & Tomorrow night -- the Geminid Meteor Shower, and it should be good!
The radiant is the perspective point where a shower's meteors would all appear to be coming from if you could see them approaching from the far distance. In reality they flash into view only when they hit Earth's atmosphere -— which can happe... | <urn:uuid:d7b87541-0ec3-40f1-ab9e-d8febfb17dd3> | 2.96875 | 837 | Personal Blog | Science & Tech. | 66.582658 |
Do homing pigeons find their way home more quickly at different times of the day?
The flight time of the homing pigeon is not affected by the time of the day.
Homing pigeons are a type of domesticated pigeons that are selectively bred from Rock pigeons. These pigeons have an innate ability to find their way home to the... | <urn:uuid:4e8849b3-60a9-4db1-a289-953588542f1c> | 3.4375 | 303 | Knowledge Article | Science & Tech. | 60.609633 |
Rocks at the Mars Pathfinder Landing Site
The content you've requested is available without charge only to active Sigma Xi members and affiliates.
If you are an active member, affiliate or individual subscriber, please log in now in order to access this article. Be sure you've entered your member or subscriber number o... | <urn:uuid:b6696006-baec-47e3-8def-322d9edc0846> | 2.9375 | 218 | Truncated | Science & Tech. | 26.917545 |
Use The Icons To Guide You
Earth Changes Calendar
Color Rows show:
Color Vertical Bands show:
All events are dated as of UTC time. Dates of your time zone may have to be adjusted occasionally for some events, which may occur the previous or next day. See Time Conversion Table below. There are a few dates which have mor... | <urn:uuid:c692db99-66f7-4c65-8832-04bee9964caf> | 3.25 | 1,835 | Structured Data | Science & Tech. | 48.719375 |
THE discovery of ancient fossils in Australia has strengthened the evidence that life began in "black smokers" deep beneath the sea.
These hydrothermal vents would have been ideal for nurturing life, some researchers have argued, as they provided a constant supply of nutrients and were protected from the ultraviolet ra... | <urn:uuid:5ea580eb-227b-4243-b34e-7d31c7547cc8> | 3.703125 | 147 | Truncated | Science & Tech. | 28.08 |
POLLEN from maize genetically modified to produce the Bt insecticide does not harm all butterflies. Lab tests last year showed the caterpillars of monarch butterflies died when they ate leaves dusted with the pollen. But field trials with an unrelated butterfly have revealed no toxic effects.
Entomologist May Berenbaum... | <urn:uuid:9789040e-78f2-4af5-9c14-0c880c907f38> | 3.109375 | 188 | Truncated | Science & Tech. | 38.741409 |
The study of past climates is important to gain an understanding of the range of natural climatic variability prior to human influences. This knowledge can help to develop more accurate computer models to predict future climate changes. Most instrumental climate records, however, only go back about 150 years, so scient... | <urn:uuid:aa4371d4-3458-4886-b5eb-5cc155911e56> | 4.0625 | 571 | Knowledge Article | Science & Tech. | 31.500707 |
|Jan4-13, 02:15 PM||#1|
omega of the second hand??
Consider a second hand in the watch. What is the constqant angular velocity.
Logicaly, i would say it travels through 1 rev in 1 min so, it is 2∏/60
However, if we look it on the other way, it has angular acceleration
so theta= (w node + w final)/2 * t gives 2∏/30 .. W... | <urn:uuid:afcbca2c-a8e2-4956-9f38-a69ffe3f4738> | 2.6875 | 249 | Comment Section | Science & Tech. | 82.827375 |
is know about the behaviors and activity within the
roosting cavities of the eastern screech owl (Otus
asio). In this live study we will observe the
behavior of the eastern screech owl inside several
roosts using artificial nest cavities fitted with
small video cameras.
Traditional methods of monitoring roosting caviti... | <urn:uuid:b1dcab82-f534-47fb-b909-839546d6f43e> | 3.234375 | 1,120 | Knowledge Article | Science & Tech. | 46.271795 |
The link between a mother and child is profound, and new research suggests a physical connection even deeper than anyone thought. The profound psychological and physical bonds shared by the mother and her child begin during gestation when the mother is everything for the developing fetus, supplying warmth and sustenanc... | <urn:uuid:1d48fab0-073e-4390-a75c-b4602b135759> | 3.21875 | 819 | Truncated | Science & Tech. | 36.969296 |
Jargon Watch: Committed Warming
Photo via Gregory Moine via Flickr CC
Committed warming - it's not necessarily a brand new idea, but rather one that makes logical sense yet we too often gloss over it. And it's important we take it into account since it impacts the way we approach combating the effects of global warming... | <urn:uuid:992698e0-12dd-4fd7-b885-e62d4583e49b> | 3.625 | 552 | Personal Blog | Science & Tech. | 51.119584 |
Let me explain.
When you define a type Integer you say that you will need at least 4 bytes to store its value. By itself Integer is just a type - you cannot store actual values in it.
But when you declare a variable:
- you say that you need a place in your app's memory heap to store the values for this variable.
the sa... | <urn:uuid:419ff4b2-2f6a-4360-8fce-0faf4f7dc621> | 2.859375 | 548 | Comment Section | Software Dev. | 36.872238 |
A man stands beside his house as smoke is seen billowing from a thermoelectric power plant in Changchun, China on April 12, 2010. China still faces challenges in the transition to a low-carbon economy and needs integrated solution systems.
"Advancing Carbon Capture and Sequestration in China: A Global Learning Laborato... | <urn:uuid:aa4d5f68-3218-4aae-bc19-284485b5b0ff> | 3.34375 | 597 | Truncated | Science & Tech. | 25.04449 |
In topology and related areas of mathematics, a metrizable space is a topological space that is homeomorphic to a metric space. That is, a topological space is said to be metrizable if there is a metric
Metrizable spaces inherit all topological properties from metric spaces. For example, they are Hausdorff paracompact ... | <urn:uuid:dc5ff856-d3bb-40a6-a00c-bb11d0251cad> | 3.1875 | 886 | Knowledge Article | Science & Tech. | 24.324513 |
TinyIDS is a distributed intrusion detection system (IDS) for Unix systems. It is based on the client/server architecture and has been developed with security in mind. The client, tinyids, collects information from the local system by running its collector backends. The collected information may include anything, from ... | <urn:uuid:8333be0d-9a03-4328-8d83-bd976151c414> | 2.9375 | 188 | Knowledge Article | Software Dev. | 39.390126 |
Lava Flows on Tolbachik|
June 14, 2013 | NASA Earth Observatory
NASA’s Earth Observatory has interesting satellite images of lava flows on Tolbachik, a volcano on the Kamchatka Peninsula. The images use visible light and shortwave infrared and near-infrared to enhance the visibility of volcanic features.
Understory Fir... | <urn:uuid:bc22ccba-f288-4799-bf9a-3a323d0cc7df> | 3.4375 | 2,140 | Content Listing | Science & Tech. | 37.331352 |
A module contains specifications and definitions that can be used by one or more program units. For the module to be accessible, the other program units must reference its name in a USE statement, and the module entities must be public.
A module takes the following form:
An automatic object must not appear in a specifi... | <urn:uuid:4da5031f-91ad-4fbe-96a2-06e7c4fd8f81> | 3.328125 | 869 | Documentation | Software Dev. | 29.805946 |
Following the recent furore about volcanic ash in the atmosphere, the UK’s Civil Aviation Authority has decided that 2mg/ m^3 is the airborne ash density below which it’s ok to fly.
Military aviators are a lot less cautious about air quality. They also have a range of countermeasures they can employ when being pursued ... | <urn:uuid:6cf9f8df-8126-4084-9150-962edc303acf> | 3.3125 | 204 | Personal Blog | Science & Tech. | 40.8725 |
The Gelechiidae is one of the largest families of microlepidoptera in the world and includes more than 4,600 described species referred to about 500 genera. About 865 named species in 94 genera occur in Western Hemisphere north of Mexico, although it has been estimated that this represents less than half of the total n... | <urn:uuid:49f02fac-668f-4ad9-a34f-c0ca299624aa> | 3.65625 | 329 | Knowledge Article | Science & Tech. | 26.812863 |
x^y gives x to the power y.
Mathematical function (see Section A.3.10).
Exact rational number results are given when possible for roots of the form .
For complex numbers and , Power gives the principal value of .
(a b)^c is automatically converted to a^c b^c only if c is an integer.
(a^b)^c is automatically converted t... | <urn:uuid:0460ac2c-61e4-4164-9280-6f0cac06ae36> | 2.8125 | 136 | Documentation | Science & Tech. | 84.325066 |
Liquid Water on Mars and the Search for Life
life on other planets? For decades this question
has been on the minds of scientists and regular people alike. Countries have sent missions to explore
space, our moon, and most recently Mars.
Picture 1 Credit to: pusillanimous.squarespace.com/ (This is a dead link I found th... | <urn:uuid:f1f8bb03-2721-4f01-8942-d219ab093f98> | 3.1875 | 1,532 | Knowledge Article | Science & Tech. | 57.473314 |
You may want to be careful about leaving the faucet running as you brush your teeth, because there might not be quite as much of that wet stuff around as you thought. An interesting graphic from the US Geological Survey provides a surprising view of just how much water there is on our little blue planet.
The image abov... | <urn:uuid:6dd23669-547a-4c08-a35a-a8adeec7f3af> | 3.140625 | 310 | Personal Blog | Science & Tech. | 60.220767 |
The movements of the wing in flight
Calliphora vicina] during flight, seen from below the horizontal plane passing through the wing-roots.
The anatomy, physiology, morphology and development of the blow- fly (Calliphora erythrocephala) A study in the comparative anatomy and morphology of insects; with plates and illust... | <urn:uuid:9fd5c784-8b0d-471a-a1ee-7a3471289716> | 2.890625 | 454 | Content Listing | Science & Tech. | 25.91017 |
y = mx + c
x = at + b, y = ct +d
Click below to see one of the Associated curves.
|Definitions of the Associated curves||Evolute|
|Involute 1||Involute 2|
|Inverse curve wrt origin||Inverse wrt another circle|
|Pedal curve wrt origin||Pedal wrt another point|
|Negative pedal curve wrt origin||Negative pedal wrt another... | <urn:uuid:0708bf12-3108-423d-bc57-37e8869cfd60> | 3.453125 | 306 | Knowledge Article | Science & Tech. | 33.544912 |
Science Fair Project Encyclopedia
It provides an accurate graphical representation of the night sky, from any location on Earth, at any date and time. The display includes up to 126,000 stars, 13,000 deep sky objects, all 88 constellations, all 8 planets, the Sun and Moon, and thousands of comets and asteroids. It has ... | <urn:uuid:d4a563bd-bde7-4934-a2fa-4368b76bcb52> | 3.390625 | 128 | Truncated | Science & Tech. | 45.258974 |
Arsenic sits right beneath phosphorus in the periodic table of the elements and shares many of its chemical properties. Indeed, that chemical closeness is what makes it toxic, Dr. Wolfe-Simon said, allowing it to slip easily into a cell’s machinery where it then gums things up, like bad oil in a car engine.
At a confer... | <urn:uuid:e76c6ff6-0a81-401f-a070-10cacbe665fa> | 3.109375 | 265 | Personal Blog | Science & Tech. | 41.60911 |
lewis dot structure h2cch2?Advertisement
I think: H2CCH2 H H | | C _ C | | H H H2NNH2: H-H-:N-N:-H-H Two Nitrogen atoms connected by single bond with a lone pair and 2 Hydrogen atoms at each ends - read more
Can You Write The Lewis Structure Of H2cch2,a Simple Hydrocarbon With C To C Double Bond? 2 Answers. Order By. V... | <urn:uuid:8a14c4a8-ecb5-4db2-ac25-cbe7d641c9f7> | 2.75 | 170 | Q&A Forum | Science & Tech. | 81.792299 |
Is there a natural solution to our carbon emissions problem?
A recent newsarticle indicated to the world that apparently the worlds plants are processing our CO2 at faster rate than previously thought and this prompted me to think, what about the concept of a carbon sink?
A carbon sink is "a natural or artificial reser... | <urn:uuid:1d2c1bbd-4939-494d-a4a8-b071c381be97> | 2.9375 | 183 | Personal Blog | Science & Tech. | 44.202941 |
42.1 Evaporation from storages
|Storage||Volume 2010–11 (ML)||Volume 2009–10 (ML)|
|Arthurs Creek Dam||22,949||25,696|
Evaporation from storages was estimated using monthly open water evaporation data produced by the Bureau. It is a Penman evaporation estimate based on daily gridded climate data and is available on a 0... | <urn:uuid:4c3e9a72-03d8-4b88-8f85-2d7fdd457b6f> | 2.90625 | 569 | Documentation | Science & Tech. | 22.595115 |
NGC4449: an Irregular Galaxy, Jeff Olivero
NGC4449 is a irregular galaxy with many regions of star formation. This galaxy is not located in the Virgo cluster like many Messier galaxies but is located in the Canes Venatici constellation. NGC4449 is 9.8 million light years away and has a magnitude of 9.4. It was discover... | <urn:uuid:0cad33d6-cfb2-4a22-af87-d2f478eae3bd> | 3.5 | 903 | Academic Writing | Science & Tech. | 63.469633 |
The human impact on the global climate is an undisputed issue. However, the fact is often ducked by political figures and special interest groups. They claim that the increases in global temperatures are not unprecedented, but very normal, and that there is no proof of the extent to which it is human actions that have ... | <urn:uuid:73a29cf5-b5d7-4a5d-9eb9-90f25eea9556> | 3.953125 | 1,115 | Personal Blog | Science & Tech. | 36.102769 |
| Moose are large and heavy, with massive heads and long noses. They have short tails, a hump on the shoulders, and large ears they can rotate. Adult males have a long, floppy dewlap - its purpose unknown - that hangs below the throat, and they grow enormous antlers each summer and shed them each winter. Moose can move... | <urn:uuid:1f0d37af-d1e1-42dc-947a-403d78ae566e> | 3.46875 | 320 | Knowledge Article | Science & Tech. | 75.569623 |
Degrees Of Certainty
Fri Feb 13 16:46:51 GMT 2009 by Vendicar Decarian
"I'm a physicist" - Genetic
Ho, Hooo.... Physicist are you? Lets check...
I have a tube that is 10 meters long and a pole that has an outside diameter that is just a fraction smaller than the inside of the tube so that the pole can be passed through... | <urn:uuid:b69d0b65-2863-42be-bfed-eb09a1a83d96> | 2.6875 | 201 | Comment Section | Science & Tech. | 72.106333 |
A common skeptic argument is that climate has changed naturally in the past, long before SUVs and coal-fired power plants, so humans can't be the cause of the current global warming. Peer-reviewed research shows this is not the case.
It's important to know there are a number of different forces acting on the Earth’s cl... | <urn:uuid:b670f2aa-df36-4eba-b319-ef5155e43c1d> | 3.984375 | 429 | Knowledge Article | Science & Tech. | 47.619266 |
Thought I'd start a new thread on this. Sugars, chemical structures and it kind of shows why they take longer/shorter to break down.
Check this out...
Maltodextrin (2-20 glucose equivalents per molecule/breaks down more slowly)
Sucrose (basically two glucose bound together, a disacride, should break down rapidly in the... | <urn:uuid:1ec31711-d365-4f61-b3d7-4eb66012c7d3> | 2.984375 | 295 | Comment Section | Science & Tech. | 52.775599 |
A fascinating study out of the University of Guelph has documented changes over time in the songs of Savannah Sparrows. Studying 800 individual birds over the course of three decades, the researchers found that certain parts of the song did not change, but others were subject to strong pressures of cultural evolution. ... | <urn:uuid:18ec3453-d3ff-457b-a5a7-46976b472939> | 3.203125 | 2,354 | Personal Blog | Science & Tech. | 51.037592 |