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Just Ask Antoine!
Atoms & ions
Energy & change
The quantum theory
Electrons in atoms
The periodic table
Acids & bases
History of chemistry
Why is the anion suffix -ide used to name molecular compounds?
- ...It states in my book that all binary compounds,molecular or ionic, all end in -ide. But why is this true if ONLY ... | <urn:uuid:0845306a-769c-4be7-895b-e9a1c5f300f2> | 3.296875 | 316 | Q&A Forum | Science & Tech. | 35.152988 |
[Home] [Puzzles & Projects] [Delphi Techniques] [Math Topics] [Library] [Utilities]
A program is required to somehow overwrite or modify email addresses in a text file to make them unidentifiable.
Background & Techniques
I recently needed to send the log file from a newsletter mailing to help diagnose a minor problem. ... | <urn:uuid:f5de287c-4698-4c4b-8f5e-4864f3d65386> | 3.046875 | 524 | Documentation | Software Dev. | 38.700812 |
I‘m peppered with emails asking me if articles like this one (which claims there is no Greenhouse Effect at all on Venus) could be right.
Michael Hammer has some 20 patents in spectroscopy, and he explains why the Greenhouse Effect — where CO2 and other gases absorb and emit infra red — is very real, and backed by empi... | <urn:uuid:3cddf73a-a27a-4328-bc54-848ab9d2c4ca> | 3.0625 | 1,347 | Personal Blog | Science & Tech. | 55.420588 |
Name: Matt D Carter
Why do organisms mutate?
Not sure if you mean "how" or "how come." If the second, then it's
because this ensures a variation in the characteristics of the offspring.
Each new generation of cheetahs includes a few who can run faster (but need
to sleep more, say) and a few who can't run as fast (but w... | <urn:uuid:7fce203f-d31d-4da2-b96d-7ab1c901cb41> | 2.796875 | 367 | Q&A Forum | Science & Tech. | 57.925 |
Pair production is not the same as decay of a particle. A particle can decay into two components according to its decay probability without needing an extra interaction. A lamda in its rest frame will decay into a proton and a pion, for example, within a predictable decay time .
There is no rest frame for the photon si... | <urn:uuid:734b5528-8f19-45f6-b536-e3e2e125e5c5> | 3.875 | 275 | Q&A Forum | Science & Tech. | 47.34306 |
This method can be used when simple, unquantified, base call quality values are available. Instead of simply counting base type frequencies it sums the quality values. Hence a column of 4 bases A, A, A and T with confidence values 10, 10, 10 and 50 would give combined totals of 30/80 for A and 50/80 for T (compared to ... | <urn:uuid:fd4916e5-d4ce-4069-be4c-462e8a602a8b> | 2.734375 | 301 | Documentation | Science & Tech. | 57.973171 |
According to astronomers studying background radiation data gathered by the Planck Space probe, the universe is 80-million years older than previously thought. So now when somebody asks you how old the universe is, you can confidently tell them, “80-million years older than previously thought” because you never knew th... | <urn:uuid:9ccf1ddd-f6c1-4bb3-a6f4-0b728c0a48f4> | 2.875 | 3,663 | Comment Section | Science & Tech. | 51.432314 |
The Fried Egg Nebula has cracked open a rare hypergiant star. A telescope in Europe recently captured the best image of the unusual cosmic phenomenon. The reason for the name is because the nebula resembles a fried egg with a yellow, yoke-like center, and a milky white around it.
The yellow hypergiant which makes up th... | <urn:uuid:263acaab-dd73-4977-87c8-ae54d2509bce> | 3.28125 | 282 | Truncated | Science & Tech. | 55.999139 |
We will write our charge distribution as a function and our current distribution as a vector-valued function , though these are not always “functions” in the usual sense. Often they will be “distributions” like the Dirac delta; we haven’t really gotten into their formal properties, but this shouldn’t cause us too much ... | <urn:uuid:2d25a8b0-223a-4af1-a990-b9c1aa83357f> | 3.59375 | 717 | Academic Writing | Science & Tech. | 36.30802 |
Learn more physics!
If there was a way it could be measured,hyphothetically, what would the gravity effect be at absolute center of the earth???
- Billy Mills (age 65)
Wadley, Georgia USA
Since there would be about equal amounts of earth at equal distances in every direction, there wouldn't be any gravitational field. ... | <urn:uuid:ba8d1eda-255a-4df9-9914-473ebc2af1d7> | 3.5 | 144 | Q&A Forum | Science & Tech. | 60.135659 |
2003 Lemelson-MIT Prize Winner
While a student at the California Institute of Technology, Leroy Hood
received words of wisdom from his mentor William Dreyer: "If
you want to practice biology, do it on the leading edge and if you
want to be on the leading edge, invent new tools for deciphering biological
information." W... | <urn:uuid:81022007-125f-4b26-b175-663ea1c670a9> | 3.265625 | 599 | Knowledge Article | Science & Tech. | 34.38 |
Amazing Discoveries in the Amazon
One of the most extraordinary species, the Ranitomeya amazonica, a frog with an incredible burst of flames on its head, and contrasting water-patterned legs. The frog’s main habitat is near the Iquitos area in the region of Loreto, Peru, and is primary lowland moist forest. The frog ha... | <urn:uuid:121b2bac-a2ff-47f9-90cf-fdbe800609e5> | 3.515625 | 524 | Knowledge Article | Science & Tech. | 29.597452 |
The achievement was detailed in the Sept. 7 edition of the journal Nature, then cited in an Oct. 10 article in the New York Times on the soccer-ball-shaped carbon molecules, which some believe may have a host of medical and industrial uses.
With Scott on the research team are former BC visiting scientist Marc Gelmont o... | <urn:uuid:c38c4afe-7946-4bff-9e83-e4af27ace496> | 3.40625 | 409 | Nonfiction Writing | Science & Tech. | 42.868757 |
A charge Q = 2.70 x 10-04
C is distributed uniformly
along a rod of length 2L, extending from y = -27.4 cm to y = +27.4
cm, as shown in the diagram above. A charge q = 4.75 x
C, and the same sign as Q, is placed at (D,0),
where D = 89.5 cm.
Consider the situation as described above and the following
If the statement is... | <urn:uuid:1d8eb9c1-8881-40d2-abcc-7030267ff57b> | 3.75 | 286 | Q&A Forum | Science & Tech. | 90.971068 |
I am using Runtime.getRuntime.exec("javac " + path + file) to compile a java file...it works just fine. Then when I use the same code to run it, Runtime.getRuntime.exec("java " + path + class) it comes back with a NoClassDeff error. Doesn't that usually mean that the classpath is not set correctly? But if I can do it w... | <urn:uuid:3a2fa520-2ac0-4d35-8c2b-484c52439e4a> | 2.75 | 245 | Comment Section | Software Dev. | 76.770537 |
© CI/photo by Stephen Richards
A rapid assessment survey of one of the three highest priorities for study in Papua New Guinea. The Muller Range had been recognized as a High Biodiversity Priority area by the Papua New Guinea Conservation Needs Assessment and was included in a World Heritage nomination. The rugged topog... | <urn:uuid:378c67f9-9ff8-477a-9dbf-56818f6e7eca> | 3.796875 | 1,316 | Knowledge Article | Science & Tech. | 29.313773 |
weevil, common name for certain beetles of the snout beetle family (Curculionidae), small, usually dull-colored, hard-bodied insects. The mouthparts of snout beetles are modified into down-curved snouts, or beaks, adapted for boring into plants; the jaws are at the end of the snout. The bent antennae usually project fr... | <urn:uuid:a4aaa30a-727a-4ace-851c-c33d28e27c83> | 3.734375 | 410 | Knowledge Article | Science & Tech. | 51.353337 |
What causes the jet stream that is caused by aircraft? Is
it dependant on the altitude of the aircraft? Do passenger aircraft have
enough speed to cause a vapor trail?
Most jet contrails are produced from passenger aircraft. On a
clear summer day it's not unusual to see the sky criss-crossed
with jet contrails.
The tem... | <urn:uuid:7040e366-b98a-480f-b574-c25d8bd1f937> | 3.890625 | 428 | Q&A Forum | Science & Tech. | 49.40015 |
|Aug3-09, 11:39 AM||#1|
question about conservation of energy/mass
I've been thinking about this problem today. I tried reasoning my way through it and I haven't been able to. I might be totally missing something obvious, so if so please feel free to laugh and point it out, but for me right now this is confusing. It de... | <urn:uuid:11d79626-ec37-4736-b705-2393ee10c472> | 3.046875 | 1,095 | Comment Section | Science & Tech. | 74.587121 |
Posted by greg2213 on May 3, 2010
Never mind that hundreds of peer-reviewed papers have shown that the Medieval Warm Period (MWP) was warmer than the present period, and word-wide, certain groups of people have scoffed at the idea that there is nothing unusual about modern times, climate-wise.
Now, even Jones, Briffa, ... | <urn:uuid:6d422728-9cda-4aa4-895c-c0fa404e2d1f> | 3.03125 | 480 | Personal Blog | Science & Tech. | 57.178421 |
Science Finds Amazing New Uses for Sound (Jul, 1931)
Science Finds Amazing New Uses for Sound
by DR. SERGIUS P. GRACE
Assistant to Vice President, Bell Telephone Laboratories As told to J. EARLE MILLER Thanks to astounding discoveries made recently in the field of sound, you will soon be able to talk around the world, ... | <urn:uuid:cda62c99-c425-4f6b-beff-dc1a7e3ce701> | 3.546875 | 3,047 | Nonfiction Writing | Science & Tech. | 38.84945 |
As if living in Hawaii weren’t a great enough life, scientists have found a kind of caterpillar there that lives the best of both worlds—in water and on land. In the Proceedings of the National Academy of Sciences, Daniel Rubinoff’s team found that 12 species in the Hawaiian moth genus Hyposmocoma are amphibious in the... | <urn:uuid:66e99843-80f2-4a38-81ac-23640d7cbf8d> | 3.515625 | 741 | Personal Blog | Science & Tech. | 41.209058 |
With about 6000 species worldwide, the morphological diversity within the brushfoots is immense. There have been decades of debates about how to classify the group and what traits are important and useful. For our purposes, the uniting characteristic of the brushfoots is the reduction of the front pair of legs into sma... | <urn:uuid:bfcd1cfc-75bf-4302-81fd-46023d71976b> | 3.328125 | 166 | Knowledge Article | Science & Tech. | 22.560923 |
Roll over Einstein: Pillar of physics challenged
Published: September 23, 2011
A startling find at one of the world’s foremost laboratories that a subatomic particle seemed to move faster than the speed of light has scientists around the world rethinking Albert Einstein and one of the foundations of physics.
Now they a... | <urn:uuid:3dccc6db-0283-414c-930b-c55487543ede> | 2.796875 | 1,042 | Truncated | Science & Tech. | 42.993553 |
The popular JUnit test framework is integrated into Android. JUnit, if used properly, brings two major benefits to the test implementation.
- JUnit enforces the hierarchical organization of the test cases
- The pattern JUnit is based on guarantees the independence of the test cases and minimizes their interference.
The... | <urn:uuid:0c4c03de-aaff-4347-9d26-3ea9327e0ff8> | 2.828125 | 679 | Personal Blog | Software Dev. | 41.566308 |
Alas, if anyone had a solid answer to this, we'd publish it and become famous exoplanet scientists.
In our own solar system, certainly most of the planetary mass is in the outer planets. The reason that is often cited has to do with the ice line. Beyond a certain distance, water and methane and other such materials are... | <urn:uuid:c5bd8f24-52df-4f6e-969f-84d5889f1dc1> | 3.375 | 456 | Q&A Forum | Science & Tech. | 36.367357 |
I understand that when you pluck a guitar string, then a bunch of harmonic frequencies are produced rather than just the frequency of the desired note. If this is true, why does C2 sound so different ...
Close ended instruments have twice the wavelength, because the wave must travel twice the distance to repeat itself.... | <urn:uuid:d4d7dbd9-157f-4ec4-a620-57976ddd0ae7> | 3.3125 | 121 | Q&A Forum | Science & Tech. | 59.736432 |
Researchers have constructed a molecular catalyzer that can oxidize water to oxygen very rapidly. In fact, these scientists have managed to reach speeds approximating those of natural photosynthesis. The speed with which natural photosynthesis occurs is about 100 to 400 turnovers per seconds. Scientists have now reache... | <urn:uuid:01382e96-0000-4e6d-84b3-69d552e16af0> | 3.53125 | 191 | Content Listing | Science & Tech. | 20.543467 |
An amazing article from the NYTimes:
Across millions of acres, the pines of the northern and central Rockies are dying, just one among many types of forests that are showing signs of distress these days.
From the mountainous Southwest deep into Texas, wildfires raced across parched landscapes this summer, burning milli... | <urn:uuid:f2417002-eda1-4536-affd-4c064e7f2248> | 3.15625 | 466 | Personal Blog | Science & Tech. | 50.055917 |
We’ll stick with the background vector space with inner product . If we want another inner product to actually work with, we need to pick out a bilinear form (or sesquilinear, over . So this means we need a transformation to stick between bras and kets.
Now, for our new bilinear form to be an inner product it must be s... | <urn:uuid:4daab168-7d7a-499f-b254-599027cca174> | 2.6875 | 555 | Personal Blog | Science & Tech. | 47.867692 |
Science Fair Project Encyclopedia
Inge Lehmann (May 13, 1888 - February 21, 1993), Fellow of the Royal Society (London) 1969, was a Danish seismologist who, in 1936, argued that the Earth must not only have a molten interior, but a solid core at the center, which deflects P waves. She also wrote a book called P, which ... | <urn:uuid:7a7ccfad-e5ea-457c-af04-b9141ed58661> | 3.09375 | 146 | Knowledge Article | Science & Tech. | 58.003173 |
Science Fair Project Encyclopedia
PNA can also refer to the Palestinian National Authority or Pakistan National Alliance .
PNA is peptide nucleic acid, a chemical similar to DNA or RNA but differing in the composition of its "backbone." DNA and RNA have a ribose sugar backbone, whereas PNA's backbone is composed of rep... | <urn:uuid:56fbb378-12b1-4d92-99e0-774de3dcfdb8> | 3.4375 | 569 | Knowledge Article | Science & Tech. | 32.800453 |
Learning Haskell with Chess
1 Exercise 1
1.1 Learning Targets
- recapitulate Haskell types (type, data, product and sum types)
- equality (in particular if using Helium)
- pretty printing pieces, boards, ...
- Define data types that represent boards, squares, positions, pieces and game states.
- Helium: Implement suite... | <urn:uuid:539f6395-8823-49d9-a64a-114a353a538d> | 3.140625 | 120 | Content Listing | Software Dev. | 36.983459 |
Time and again, extreme claims about global warming (aka global climate change) turn out to be lacking in one major aspect. That aspect is truth. Today’s story from the London Telegraph tells how the warmest October on record could be explained, considering the unusual cold, snow, and ice activity around the world duri... | <urn:uuid:b80b7022-4a4f-465b-a889-11fb4c2b0125> | 2.984375 | 207 | Personal Blog | Science & Tech. | 44.431667 |
(PHP 4 >= 4.3.0, PHP 5)
proc_close — Close a process opened by proc_open() and return the exit code of that process
proc_close() is similar to pclose() except that it only works on processes opened by proc_open(). proc_close() waits for the process to terminate, and returns its exit code. If you have open pipes to that... | <urn:uuid:619408ee-f4f4-4d6b-961b-e0e384674044> | 2.71875 | 188 | Documentation | Software Dev. | 59.025997 |
The sun put on quite the display this May Day. It unleashed a colossal wave of super-hot plasma into space. Known as a coronal mass ejection (CME), this spectacular event was caught on camera by NASA scientists.
Are you a poet and you didn't even know it? Well, now you can be. For those of the galactic persuasion, NASA... | <urn:uuid:96df60b3-d6ad-4189-bfb6-28d880fb3e3a> | 2.734375 | 544 | Content Listing | Science & Tech. | 57.91998 |
Do we need to retrench, pull back from the coasts because of sea-level rise or rebuild differently? Where do we go from here?
We need an integrated approach that covers three areas: engineering, ecologically based adaptation and policies. Let's take engineering. There is a whole spectrum of engineering approaches, like... | <urn:uuid:9c274719-d654-465b-979e-36acb20d9dc0> | 2.6875 | 746 | Audio Transcript | Science & Tech. | 53.17338 |
A UVV MAX is a region of lifting air in the atmosphere. This lifting is on the large scale. Some example lifting processes are orographic lifting, low level warm air advection, divergence aloft, frontal lifting, and convergence in the lower troposphere. The region with the greatest amount of lifting will be at the bull... | <urn:uuid:5586622f-217e-4bbe-a4d0-18189e5df7bc> | 3.4375 | 159 | Knowledge Article | Science & Tech. | 49.256178 |
Title: National database for calculating fuel available to wildfires
Author: McKenzie, Donald; French, Nancy H.F.; Ottmar, Roger D.
Source: Eos. 93(6): 57-58
Description: Wildfires are increasingly emerging as an important component of Earth system models, particularly those that involve emissions from fires and their ... | <urn:uuid:93e2fca5-0068-4030-9b0e-73d84f894420> | 2.9375 | 406 | Truncated | Science & Tech. | 33.135065 |
Climate and Global Change
Warm near the equator and cold at the poles
, our planet is able to support a variety of living things because of its diverse regional climates
. The average of all these regions makes up Earth's global climate
. Climate has cooled and warmed throughout Earth history
for various reasons. Rapid... | <urn:uuid:f640adaa-2d33-4c40-bbd7-03ad27b4bcc4> | 3.578125 | 115 | Knowledge Article | Science & Tech. | 37.192545 |
(Note: We discuss carbon dioxide because it contributes to slightly over half of current greenhouse warming, but we must remember that methane, CFCs, ozone, and nitrous oxide together account with slightly less than half).
When I was a graduate student at the University of Washington, learning about weather and climate... | <urn:uuid:49b97676-baaa-4d81-aa44-6be861600bc1> | 3.5 | 643 | Personal Blog | Science & Tech. | 55.507903 |
(a) Time evolution in the proposed experiment for past-future entanglement extraction. In the first time interval, qubit P interacts with the vacuum field. After a certain time with no interaction, qubit F interacts with the field, getting entangled with qubit P. (b) To activate and deactivate qubit-field coupling, the... | <urn:uuid:d131704f-51c5-4812-8d29-d7591fb1b96a> | 3.5625 | 542 | Academic Writing | Science & Tech. | 32.905344 |
Which invasive species is most established in the Bay?
More than 5,000 alien species have become established in North America since the founding of the English Colony at Jamestown. Of these, the Maryland Invasive Species Council has identified about 100 that present a serious threat in our region.
Which one is the wors... | <urn:uuid:b63a1a00-11f5-42f4-8cdf-dbb90f7b7ace> | 3.15625 | 276 | Q&A Forum | Science & Tech. | 46.31027 |
Wellman, C.H., Osterloff, P.L. and Mohiuddin, U. (2003) Fragments of the earliest land plants. Nature, 425 (6955). pp. 282-285. ISSN 0028-0836Full text available as:
The earliest fossil evidence for land plants comes from microscopic dispersed spores. These microfossils are abundant and widely distributed in sediments,... | <urn:uuid:320316fc-ce87-4d42-9884-134148f2296d> | 3.59375 | 406 | Academic Writing | Science & Tech. | 29.009159 |
This is pretty tedious. The IPCC tells us that carbon dioxide actually has very little influence on earth’s greenhouse effect. That’s probably sent a lot of greenhouse hysterics into a dead faint so I’d better explain.
The IPCC provides the formula to demonstrate that CO2 constitutes less than 10% of earth’s greenhouse... | <urn:uuid:fae9ce24-128f-4547-927a-22202318abb0> | 3.28125 | 722 | Personal Blog | Science & Tech. | 61.197102 |
HTML5 has a lot of cool things in it, but the one thing I wish I could remove are data-attributes, because of the crimes against clean front-end code that it seems to encourage.
What is this clean web code you speak of?
This is the language we use to declaratively set the visual properties of our UI. It consists of a p... | <urn:uuid:f27861a8-5dde-4815-989c-25cb1426960b> | 2.71875 | 763 | Personal Blog | Software Dev. | 63.883715 |
The Local Group contains more than 35 galaxies, most of which are dwarf ellipticals and irregulars with low mass; this complicated system may be considered as being formed by two main galaxies, M31 and the Milky Way, with other dynamically less important satellites belonging either to one of them or to the pair.
This p... | <urn:uuid:2837604f-0d28-4c04-a85b-296e5c110e91> | 2.828125 | 3,133 | Academic Writing | Science & Tech. | 51.812223 |
Three children are going to buy some plants for their birthdays. They will plant them within circular paths. How could they do this?
On my calculator I divided one whole number by another whole number and got the answer 3.125 If the numbers are both under 50, what are they?
Have a go at this well-known challenge. Can y... | <urn:uuid:66dcb9a2-704f-40de-a5ba-0a697590b0bd> | 2.765625 | 222 | Q&A Forum | Science & Tech. | 92.29111 |
The fact that ADT are closed makes it a lot easier to write total functions. That are functions that always produce a result, for all possible values of its type, eg.
maybeToList :: Maybe a -> [a]
maybeToList Nothing =
maybeToList (Just x) = [x]
Maybe were open, someone could add a extra constructor and the
maybeToLis... | <urn:uuid:48af348d-5270-4dd2-a24c-8abb3857fdcb> | 2.921875 | 325 | Q&A Forum | Software Dev. | 49.931752 |
How to determine atmospheric extinction
Use this table to refine your comet observing.
October 26, 2009
In the December 2009 issue, I wrote the story, "How to observe comets." In it, I suggest all observers estimate how bright a comet appears. To get the whole picture, however, you must factor in one other thing.
This ... | <urn:uuid:0e0a6393-e952-4af9-89ce-1ff9f7151ccd> | 3.25 | 259 | Truncated | Science & Tech. | 43.75674 |
Radiation Induced Chemical Reactions 1947-67
Brookhaven over the last twenty years has taken a leading role in the
study of chemical effects of radiation and in the conversion of this subject
from empirical groping to a sophisticated branch of chemical science. The
aim in this field is, first, to infer what reactions a... | <urn:uuid:e3aa125e-02da-46ea-a191-005d124fa3d8> | 3.28125 | 894 | Knowledge Article | Science & Tech. | 48.226414 |
MakefilesMakefiles are something of an arcane topic--one joke goes that there is only one makefile in the world and that all other makefiles are merely extensions of it. I assure you, however, that this is not true; I have written my own makefiles from time to time. In this article, I'll explain exactly how you can do ... | <urn:uuid:15f954cd-52fa-47cb-98bd-c02ecd5950b1> | 3.140625 | 1,543 | Tutorial | Software Dev. | 44.178618 |
lightning, electrical discharge accompanied by thunder, commonly occurring during a thunderstorm. The discharge may take place between one part of a cloud and another part (intracloud), between one cloud and another (intercloud), between a cloud and the earth, or earth and cloud; more rarely observed is the electrical ... | <urn:uuid:44337ccc-89bb-4dfa-8020-ae6a141e4ca9> | 3.671875 | 378 | Knowledge Article | Science & Tech. | 27.375409 |
Western Bark Beetle Strategy Glossary
Aggregating pheromone - chemical compound released by an insect (male or female) to attract others of its species.
Bark beetles - group of beetles, mainly of the family Scolytidae, whose adults bore through the bark of host trees to lay their eggs, and whose larvae tunnel and feed ... | <urn:uuid:199f2436-a019-441c-b9c5-078a9c960ada> | 3.4375 | 569 | Structured Data | Science & Tech. | 23.326452 |
The 20 Hottest Years on Record
Global Warming 101
Global average surface temperatures pushed 2005 into a virtual tie
with 1998 as the hottest year on record. For people living in the Northern
Hemisphere—most of the world's population—2005 was the hottest year
on record since 1880, the earliest year for which reliable i... | <urn:uuid:04bf35e3-2665-4368-b3a7-15c6057e2aec> | 3.78125 | 2,919 | Content Listing | Science & Tech. | 58.821431 |
Exploring Mars Image Center
Most of these image collections are based on Lunar and Planetary Institute slide sets and include explanatory captions, a locator map, a glossary, and suggested references for further study.
|The Red Planet: A Survey of Mars
An overview of Mars, including its volcanos, the Valles Marineris c... | <urn:uuid:43130bc8-810d-43ce-baee-f2c9f032c373> | 3.140625 | 322 | Content Listing | Science & Tech. | 36.174346 |
Our voyage through the solar system, in search of conditions in which life could originate, has encountered an enormous diversity of habitats--from the dry soils of Mars to the sulphurous geysers of Io and the ocean of Europa. Several space missions are planned for the coming decade that may shed more light on the issu... | <urn:uuid:f94020cb-1a34-47a8-ac10-85a8486a3dc1> | 4.0625 | 1,280 | Knowledge Article | Science & Tech. | 36.148228 |
Bryozoans can be found in the following collections that may be useful for ocean acidification studies:
The Discovery collections originate from a number of different expeditions that took place from 1901-1999. The collection of pteropods may be of particular importance for ocean acidification research, and there are a... | <urn:uuid:a909ca8d-4c5e-42d4-9a36-ede251c7cd4c> | 3.359375 | 207 | Knowledge Article | Science & Tech. | 25.317424 |
Opening a new window into the mysteries of animal design and the nature of life, biologists described here today how they had decoded almost the entire genetic rule book for making the Drosophila fruit fly, an organism whose study is deeply interwoven with the progress of modern biology.
The achievement closes a cycle ... | <urn:uuid:7d4025ce-aa6d-4036-a12b-9d9345a78647> | 3.15625 | 717 | Truncated | Science & Tech. | 44.027688 |
An Introduction to WSIL
Pages: 1, 2
Locating WSIL Files
Once an inspection document has been created, a consumer needs to be able to find it. WSIL's decentralized document-based model would make locating these files difficult if it were not for a couple of simple conventions defined in the specification.
The first conv... | <urn:uuid:2f170692-cb4d-49b6-b9c6-01ac28727c0b> | 2.78125 | 2,404 | Nonfiction Writing | Software Dev. | 39.759259 |
Eight Weeks of Prototype: Week 1, Beginning with Prototype
DOM Traversal Methods
In addition to being able to select elements in the DOM using
select(), Prototype also allows you to select elements using the
down(), next() and
previous() methods. These methods help you to easily find elements relative to a given elemen... | <urn:uuid:5600b974-3dc8-44d7-b800-a6ad46a841f5> | 3.796875 | 1,151 | Tutorial | Software Dev. | 50.74732 |
Although there is substantial evidence that Northern Hemisphere species have responded to climatic change over the last few decades, there is little documented evidence that Southern Hemisphere species have responded in the same way. Here, we report that Australian migratory birds have undergone changes in the first ar... | <urn:uuid:10332d17-c836-4593-8b7e-60c3ae4f8e6a> | 3.28125 | 576 | Academic Writing | Science & Tech. | 35.073248 |
In the 1970s, Apollo-era astronauts left a seismic experiment on the moon. Now, new analysis of 30-year-old data from the Apollo Passive Seismic Experiment may give new insights into the lunar core. Researchers report that the lunar core may be much like the core of the Earth, with a solid inner core and molten outer c... | <urn:uuid:9b6d0aa4-6993-49ab-8e2b-eea1e106e70f> | 3.15625 | 120 | Truncated | Science & Tech. | 49.681816 |
Have you ever wondered how clouds form? We all learn the water cycle in school – water falls from the clouds in the form of rain or snow and collects on the ground. The water on the ground heats up and turns to vapor and the vapor travels up into the atmosphere and creates clouds.
But how do those clouds form? Here’s a... | <urn:uuid:224eea93-acbc-4445-9488-4248b4d2a6c1> | 3.34375 | 728 | Personal Blog | Science & Tech. | 58.237566 |
In this section...
7.2.1 Predefined Numeric Types
7.2.2 Ada Model
7.2.4 Accuracy Constraints
7.2.6 Precision of Constants
7.2.7 Subexpression Evaluation
7.2.8 Relational Tests
|Summary of Guidelines from this section|
Standard. Use range and digits declarations and let the implementation do the derivation implicitly fr... | <urn:uuid:8c554dc4-0b31-4ee8-b5f6-4e070144bdf9> | 2.859375 | 1,104 | Documentation | Software Dev. | 51.444411 |
Glenn Chaple's observing basics: A star by any other name
February 2005: What is the identity of the star BD +88°8? How about HD 8890, BS 424, or SAO 308? If you're still shaking your head, I have a surprise for you.
February 1, 2005
|Quick trivia question: What is the identity of the star BD +88°8? Never heard of it? ... | <urn:uuid:55996e6f-32e8-4b49-8560-ec52a9d5d807> | 2.6875 | 320 | Truncated | Science & Tech. | 60.430034 |
Nature: Thanks to their ability to switch on and off and amplify signals, transistors are a key component of electrical devices. Several projects have demonstrated the possibility of creating transistors that are controlled by photons instead of electrical signals. The most recent, created by Wenlan Chen of MIT and her... | <urn:uuid:65fcca32-625c-4464-97d5-5f2848eb28ae> | 3.859375 | 1,927 | Content Listing | Science & Tech. | 38.152936 |
Part 14 - Exceptions
A mechanism designed to handle runtime errors or other problems (exceptions) inside a computer program.
Exceptions are very important, as they are raised whenever an error occurs in the system. (Or at least they should be.)
An exception stops the program if it is not caught.
Which stopped the progr... | <urn:uuid:9af48e83-d256-49d7-87b4-bea6a1ee8f1e> | 4.1875 | 276 | Documentation | Software Dev. | 52.097727 |
Not nearly as spectacular as astrophysical or planetary missions, magnetospheric studies are nevertheless closer to the Earthling's wellbeing, since plasma environment in the immediate vicinity of the Earth is far greater factor than distant supernovae explosions or methane in the Martian atmosphere. Earth’s magnetosph... | <urn:uuid:2daef1c8-4c6b-496c-ac99-3f66e9f86586> | 3.625 | 876 | Knowledge Article | Science & Tech. | 20.551684 |
See also the
Dr. Math FAQ:
Browse High School Euclidean/Plane Geometry
Stars indicate particularly interesting answers or
good places to begin browsing.
Selected answers to common questions:
Pythagorean theorem proofs.
- The Role of Postulates [03/29/2003]
Who decided what were postulates and what were theorems? Why is... | <urn:uuid:b922b552-1a0e-4674-8915-f62f8c5c757d> | 3.125 | 1,851 | Q&A Forum | Science & Tech. | 69.50813 |
Plants and Freezing
I'd like to know is it possible to freeze a plant
and revive it? If so, what mechanisms are involved?
While this might be possible with some rare species of plants, in general it
is not viable to do this. When you freeze a plant the water in each of the
cells freezes, which expands and lyses the cel... | <urn:uuid:8ab6ded3-78b3-4991-ae82-d13354161d09> | 2.6875 | 296 | Q&A Forum | Science & Tech. | 55.464725 |
Pomona College Magazine
Volume 40, No. 3
Sidebar: Pluto or Bust
Three billion miles.
Nine years of rocket-powered space flight, just to get to a place where the sun is merely the brightest star in the sky.
Ask Colleen Hartman why she fought so hard to help sell NASA on the upcoming "Pluto mission," and the former direc... | <urn:uuid:25c2e9a3-73ae-4f3a-94f8-195a0969e015> | 2.921875 | 752 | Truncated | Science & Tech. | 53.871881 |
SchrodingerZ writes "Though solar eclipses are fairly common on Earth (much more in the southern hemisphere), yesterday the Mars Curiosity Rover caught sight of a partial solar eclipse in Gale Crater on the Red planet. The martian moon Phobos took a small bite out of the sun on the 37th day (Sol 37) of the rover's mart... | <urn:uuid:fddc18d3-9e81-4b12-aed2-eb1e9a8c04b8> | 3.0625 | 174 | Comment Section | Science & Tech. | 49.024643 |
Launch Date: August 30, 1991
Mission Project Home Page - http://www.lmsal.com/SXT/
The Yohkoh Mission is a Japanese Solar mission with US and UK collaborators. It was launched into Earth orbit in August of 1991 and provided valuable data about the Sun's corona and solar flares. The satellite carried four instruments - ... | <urn:uuid:12e0f5ac-eebf-4764-8df2-e10d6b669934> | 3.34375 | 588 | Knowledge Article | Science & Tech. | 52.344466 |
Added 1 new A* page:A lot of what NASA does isn't just looking out at space, but looking back at Earth *from* space. For instance, how 'bout them forests?|
A map released in 2010 showed forest heights around the world, with a particular focus on the continental United States. Using readings from reflected laser pulses ... | <urn:uuid:e2dcbd00-19a3-427b-a752-22623c09b00c> | 4.03125 | 895 | Knowledge Article | Science & Tech. | 50.999276 |
Summary for Ozyptila nigrita (Araneae)
Explore Regional Distribution
Please log on and add a note on this species
About this speciesDistribution
The species is confined to southern England. It is widespread in north-western and central Europe as far north as Sweden, but has not been recorded from Ireland.
Habitat and e... | <urn:uuid:be8d6a24-37b7-4808-832d-51e818ef38ae> | 2.953125 | 260 | Knowledge Article | Science & Tech. | 44.963865 |
First results from a new instrument:
Greenland--Greenland's ice sheets are melting extensively, even in some inland areas, according to an image generated from data obtained by a Japanese climate-observation satellite.That picture is astounding. Here's a picture of melting days in 1992, and again ten years ago in 2002:... | <urn:uuid:b9ad016d-f6d7-4df4-8608-9ef0663eb557> | 3.421875 | 307 | Personal Blog | Science & Tech. | 51.040085 |
Further to Greenland's current warming & melting glacier's, I bring you this analysis of a paper published in Nature Geoscience:
model simulations show that "ice acceleration, thinning and retreat begin at the calving terminus and then propagate upstream through dynamic coupling along the glacier." What is more, they f... | <urn:uuid:ba74f3a5-6e9c-4a12-bdab-a2df6d379adb> | 2.84375 | 1,972 | Comment Section | Science & Tech. | 36.031847 |
is not a new phenomenon, nor is extinction. Many times in Earths history,
the climate has changed sometimes rapidly and drastically and
species have become extinct. At least five times, more than 50 percent of species
inhabiting the planet have died out, and as few as 2 to 4 percent of the species
that have ever lived ... | <urn:uuid:9673532a-e17a-43d6-a5ea-30ed37b1765e> | 3.9375 | 1,682 | Knowledge Article | Science & Tech. | 32.367554 |
Revision Control with Arch: Introduction to Arch
Arch quickly is becoming one of the most powerful tools in the free software developer's collection. This is the first in a series of three articles that teaches basic use of Arch for distributed development, to manage shared archives and script automated systems around ... | <urn:uuid:7d39614a-a9e2-4b5f-b07c-e5a7b42cfaf5> | 2.8125 | 1,471 | Content Listing | Software Dev. | 36.629154 |
When a car ignition coil increases the voltage from 12v DC
to 10,000v DC, what happens to the value of the current? Voltage and
current have a direct relationship. Does the current increase also?
Nope. As voltage is increased, current DEcreases. What stays the same is power,
which is voltage times current.
Richard Barr... | <urn:uuid:b2f20f11-b3a5-4b73-81d1-14375c0b9159> | 2.90625 | 1,195 | Q&A Forum | Science & Tech. | 53.035269 |
Animals and Homing
Name: Belle M.
How do birds like homing pigeons know where to go to a
place that is hundreds of miles away? Cats and dogs can do this to does
it have to do with the earth's magnetic fields
This is one of the great mysteries of the animal world. I don't think anyone knows the
answer for sure yet, desp... | <urn:uuid:9d0ac0f9-071c-4a5a-8ddb-921c1805be0b> | 3.1875 | 214 | Knowledge Article | Science & Tech. | 52.535698 |
6. Recent HRIBF Research - Use of 7Be Beam in Wear
Studies (Proof-of-Principle Experiment)
[U. Greife (Colorado School of Mines), spokesperson]
Currently in the United States, about 200,000 hip-joint replacement surgeries are performed each year. Worldwide, the number is nearly 1 million [DeG04, Feh00]. Unfortunately, ... | <urn:uuid:8e675e81-1382-4634-a4ab-abff95c02e61> | 2.921875 | 1,167 | Academic Writing | Science & Tech. | 44.731244 |
Fick Calendar Home
A Near Miss
On August 18, 2002, asteroid 2002 NY40 passed within 325,000 miles of Earth.
If this fact doesn't scare you just a little bit, it should. This is a
near-miss - it passed just 1.3 times farther from the Earth than the distance
to the Moon.
2002 NY40 is an example of a Near-Earth Object, or... | <urn:uuid:8ff2f07b-8477-43e8-a40d-d762876714af> | 3.484375 | 307 | Knowledge Article | Science & Tech. | 79.411857 |
Atlas recording spawning and nursery areas of fish in the Great Lakes and associated rivers listed by area and then by species. A 14-volume atlas in PDF format. Published in 1982 by the U.S. Fish and Wildlife Service.
Manual for research program on the nesting habits of sea turtles of the Virgin Islands, with descripti... | <urn:uuid:24fabb3d-f5d5-49de-938b-8025a10ee86e> | 2.6875 | 192 | Content Listing | Science & Tech. | 39.136429 |
This is an image of Saturn in false color.
Click on image for full size
Saturn's Belts and Zones
The striped cloud bands on Saturn, like Jupiter, are divided into belts and zones.
In a belt, the wind flows very strongly in one direction only. In a zone, the wind flows very strongly in exactly the opposite direction. Th... | <urn:uuid:57793021-10a4-432b-b3be-5f3a713f9c5a> | 3.5 | 535 | Content Listing | Science & Tech. | 66.320458 |
An Open Universe
Click on image for full size
An Eternal Universe
If the universe does not contain enough matter to stop its expansion it will continue to expand forever.
Using the currently understood laws of physics we can project into the future what the Universe may look like in very distant eras. Two astrophysicis... | <urn:uuid:581ba702-b04c-422b-a719-a38ab41cc327> | 3.59375 | 702 | Content Listing | Science & Tech. | 54.986409 |
In a brief review regarding the nature of supernovae, Italian astronomer Nino Panagia highlights the major issues associated with the current understanding of supernovae. Panagia points out that while supernovae of Type Ia are used as perfect “standard candles” (that is, distance markers), they are not so perfect. Type... | <urn:uuid:e7d35175-60ea-405b-ae67-b0fac487dc4d> | 3.0625 | 848 | Content Listing | Science & Tech. | 51.333865 |
Yesterday morning, when scanning the news at spiegel online, a headline in the science section made me curious: Bleistift statt schwarzer Löcher, pencils instead of black holes. That short piece turned out to be a quite sensible description of a recent experiment on the Klein paradox in single layers of graphite. There... | <urn:uuid:d7343616-d905-48a4-b41f-8cad14562c8c> | 2.984375 | 1,099 | Personal Blog | Science & Tech. | 40.996807 |
An experiment aimed at recreating the domestication of wolves and their subsequent evolution into the modern dog has yielded an unexpected benefit for anyone who has ever wished to be the owner of a pet fox.
|Tod from ''The Fox and The Hound'|
The experiment was begun in 1959 by biologist Dmitry Belyaev, and continues ... | <urn:uuid:4254c73e-5c01-4811-b70c-627144f74b69> | 3.515625 | 806 | Knowledge Article | Science & Tech. | 42.151618 |
Tuesday, April 6, 2010
The Ethiopean Amber
Image courtesy PNAS/ Matthias Svojtka
This is really neat: the American Museum of Natural History reports the discovery of a nice chunk of Cretaceous amber from Ethiopia. While pieces of the translucent golden fossilized tree resin are well known from other parts of the world,... | <urn:uuid:c2a1bd43-7b72-486a-9c89-c14693b19fb7> | 3.09375 | 526 | Personal Blog | Science & Tech. | 43.911 |
An electrolyte which gives ions of which at least one is of colloidal
size. This term therefore includes hydrophobic sols
, ionic association colloids
, and polyelectrolytes.
PAC, 1972, 31, 577
(Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols... | <urn:uuid:ab0f91ae-00ef-48b8-b83a-8eb47812197d> | 3.046875 | 202 | Structured Data | Science & Tech. | 58.49886 |
Credit: Image courtesy of K. Iwasawa, G. Miniutti and A. Fabian and ESA.
What must it be like near a black hole? The intense gravity generated by the singularity at the heart of the black hole should produce all sorts of strange behavior, as predicted by Einstein's Theory of Relativity. We probably won't ever have a fi... | <urn:uuid:d9e00aa4-33e3-4608-8fe8-a3a46367e337> | 3.71875 | 320 | Truncated | Science & Tech. | 57.582591 |
Simply begin typing or use the editing tools above to add to this article.
Once you are finished and click submit, your modifications will be sent to our editors for review.
...centimetres in width, while the butterfly Ornithoptera victoriae of the Solomon Islands has a wing span exceeding 30 centimetres. One of the lo... | <urn:uuid:9ba3da42-942b-4257-b542-43006477c9ba> | 2.84375 | 154 | Knowledge Article | Science & Tech. | 48.493821 |
In fluid dynamics, turbulence or turbulent flow is a fluid regime characterized by chaotic, stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time. Flow that is not turbulent is called laminar flow. The (dimensionless) ... | <urn:uuid:7b797acf-95bb-40c4-8dd0-10c27b6a57ed> | 3.640625 | 440 | Knowledge Article | Science & Tech. | 36.620712 |
|MadSci Network: Evolution|
I'll assume from your mention of dentition that you are sticking with mammals only. I think this is fine because this is the group that is most easily identifiable to a class of first year students and they show the most divergence. Eyesight and dentition are good starts and can be easily sh... | <urn:uuid:91d5ba3d-812c-4459-b19c-393965bb6ff1> | 3.296875 | 461 | Comment Section | Science & Tech. | 27.466853 |
A somewhat derogatory term “bourbakism” proliferates in many public
discussions about mathematics and the ways of teaching mathematics. We hear many funny
anecdotes about commutativity as a method of calculation
as well as separate addition of nominators and denominators.
Professional mathematicians and teachers divide... | <urn:uuid:d9d3d89b-05f3-407d-8af2-92e1cdbc9e5c> | 3.171875 | 2,264 | Nonfiction Writing | Science & Tech. | 26.964448 |
The world's second largest ice cap may be melting three times faster than indicated by previous measurements, according to newly released gravity data collected by satellites.
The Greenland Ice Sheet shrank at a rate of about 239 cubic kilometres per year from April 2002 to November 2005, a team from the University of ... | <urn:uuid:1cbc8d05-4e31-4b1d-98cf-7236e61728c0> | 3.890625 | 1,392 | Comment Section | Science & Tech. | 54.718559 |
Last updated 05 April 2013, created 20 March 2012, viewed 660
Use these pictures from the Encyclopaedia Britannica to learn about volcanoes. A volcano is an opening in Earth's crust. When a volcano erupts, hot gases and melted rock from deep within Earth find their way up to the surface. This material may flow slowly o... | <urn:uuid:f011e68b-2ab4-4df1-9f0d-8b52f5fc39d8> | 3.6875 | 129 | Knowledge Article | Science & Tech. | 61.205 |
The Science Guys
Science Guys > June 2001
Why does a stream of water from a faucet become smaller at it falls?
Everyone has seen this phenomenon in their home. Turn on the water and adjust it so that the water flows in a steady, smooth manner (called laminar flow). You will observe that the stream narrows as it falls t... | <urn:uuid:e143d54e-0fa0-4d4c-a26e-80cc19266ab7> | 3.953125 | 750 | Tutorial | Science & Tech. | 67.900078 |