C&EN: IT'S ELEMENTAL: THE PERIODIC TABLE - INTRODUCTION National Chemistry Week, October 19-24, 2009 NCW kicks off this week with the theme "Chemistry—It's Elemental!" Visit www.acs.org/ncw for more information. The Periodic Table is nature’s rosetta stone. To the uninitiated, it’s just 100-plus numbered boxes, each containing one or two letters, arranged with an odd, skewed symmetry. To chemists, however, the periodic table reveals the organizing principles of matter, which is to say, the organizing principles of chemistry. That’s not to say, of course, that all of chemistry is obvious from the periodic table. Indeed, as John Emsley notes in his invaluable book, “Nature’s Building Blocks: An A–Z Guide to the Elements,” Mendeleyev never accepted that electrons came from atoms because he was convinced that atoms were indivisible. No matter. The periodic table is so central to chemistry that it seemed natural to devote a special issue to it and the elements that compose it as we celebrate C&EN’s 80th anniversary. Top
Periodic Table - Interactive Periodic Table of the Elements This is an online interactive periodic table of the elements. Click on an element symbol in the periodic table to get facts for that element. Printable periodic tables and a list of elements by increasing atomic number are also available. More Periodic Table Information Introduction to the Periodic Table People have known about elements like carbon and gold since ancient time. What is the Periodic Table? Dmitri Mendeleev was the first scientist to create a periodic table of the elements similar to the one we use today. Why was the Periodic Table Created? Many elements remained to be discovered in Mendeleev's time. Discovering Elements The number of protons determines the atomic number of an element, which is its number on the periodic table. Element Properties and Trends The periodic table helps predict some properties of the elements compared to each other. Today's Periodic Table Periods and Groups Elements in the periodic table are arranged in periods (rows) and groups (columns). Periods
7 Man-Made Substances that Laugh in the Face of Physics | Cracke The universe is full of weird substances like liquid metal and whatever preservative keeps Larry King alive. But mankind isn't happy to accept the weirdness of nature when we can create our own abominations of science that, due to the miracle of technology, spit in nature's face and call it retarded. That's why we came up with... #7. What do you get when you suspend nanoparticles of iron compounds in a colloidal solution of water, oil and a surfactant? A ferrofluid is a liquid that reacts to magnetic fields in trippy ways that make you think that science is both magical and potentially evil. Tell us that didn't look like the birth of the most sinister dildo ever. What happens is that when a magnetic field is applied to the fluid, the particles of iron compound inside align to it. What the Hell is it Used For? Ferrofluids have a lot of pretty mundane uses, from lubricating and protecting hard drives to providing heat conduction in speakers, but their primary use is in looking cool. #6. #5.
Royal Society of Chemistry | Advancing the Chemical Sciences Tip : Locking layers Back to french version... So, what is the problem ? How many times, working on rendering I forgot to display some layers ? Then I throw it away and redo the render. The solution ? A small button which, apparently, the effect is largely unknown or misunderstood. Layers locked Layers unlocked By default, it is like this , locked. But actually what is it ? Let's take an exemple. Objects are distributed on different layers to easily work on each part separately. If I want to work on the selected object, I have several choices: I can zoom in the 3D view in Wire display but then the other objects will disturb me to position the selection. And if I go to Solid , it's worse , I can not see anything . Indeed , hard to work with such visibility. So what we do is displaying only the wanted layer by clicking on it, but there, our set of layer for rendering is lost . So I need to know by heart Lightbox layers to render. Then the unlocking effect ! So I unlock layers in my 3D view. Better ! Summary
La Ligne du Temps de la Chimie Préambule Toute science progresse par la réalisation et l'interprétation d'expériences, par l'introduction de nouveaux concepts, ... Des améliorations et corrections se succèdent alors, dévoilant parfois des erreurs ou des imprécisions du passé. Dans de nombreuses situations, la recherche scientifique induit des interrogations sur l'articulation des travaux actuels par rapport à la masse des connaissances précédentes. La présentation choisie, une ligne du temps, constitue un support chronologique pour une meilleure connaissance de la chimie, basée sur les expériences et découvertes fondamentales qui ont permis l'avancement de la science. L'aspect chronologique est (sera) complété par des hyperliens permettant une approche historique plus thématique. Au-delà de la présentation d'une liste impressionnante de découvertes, on peut trouver dans cette page un moyen d'aborder l'histoire des sciences, sans évidemment remplacer un cours ou un ouvrage spécialisé dans ce domaine. Note de l'auteur
50 Tips for Working with Unity (Best Practices) About these tips (Edit: August 2016. I have revised these tips. You can find the new list here.) These tips are not all applicable to every project. They are based on my experience with projects with small teams from 3 to 20 people.There’s is a price for structure, re-usability, clarity, and so on — team size and project size determine whether that price should be paid.Many tips are a matter of taste (there may be rivalling but equally good techniques for any tip listed here).Some tips may fly in the face of conventional Unity development. Process 1. 2. 3. 4. It makes it unnecessary to re-setup each scene.It makes loading much faster (if most objects are shared between scenes).It makes it easier to merge scenes (even with Unity’s new text-based scenes there is so much data in there that merging is often impractical in any case).It makes it easier to keep track of data across levels. You can still use Unity as a level editor (although you need not). 5. Scene Organisation 6. 7. 8. 9. 10. Art
Game Programming Patterns Hey, Game Developer! Do you struggle to make your code hang together into a cohesive whole? Find it harder to make changes as your codebase grows? Feel like your game is a giant hairball where everything is intertwined with everything else? Wonder if and how design patterns apply to games? I’m here to help! It’s Free and Online! This is the book I wish I had when I started making games, and I want you to have it now! Want to read it on paper/eBook? I’m working on those now! (I post less than once a month. Start Reading! Who Am I? I’m Bob Nystrom. The Gene School - Gene Splicing As of July 1, 2013 ThinkQuest has been discontinued. We would like to thank everyone for being a part of the ThinkQuest global community: Students - For your limitless creativity and innovation, which inspires us all. Teachers - For your passion in guiding students on their quest. Partners - For your unwavering support and evangelism. Parents - For supporting the use of technology not only as an instrument of learning, but as a means of creating knowledge. We encourage everyone to continue to “Think, Create and Collaborate,” unleashing the power of technology to teach, share, and inspire. Best wishes, The Oracle Education Foundation
The Biology Project: Biochemistry Chemistry of Life Chemistry Review the basics of chemistry you'll need to know to study biology. Large Molecules Learn about structures and properties of sugars, lipids, amino acids, and nucleotides, as well as macromolecules including proteins, nucleic acids and polysaccharides. Chemistry of Amino Acids learn the structure and chemistry of the amino acids that are found within proteins. Acids & Bases Learn about the solvent properties of water, pH, pKa and buffering capacity. Clinical Correlates of pH Levels Learn how metabolic acidosis or alkalosis can arise and how these conditions shift the bicarbonate equilibrium. B12/Folate Learn which biological reactions require either B12 or folate (or both); what the consequences of a deficiency in either vitamin are, and the important step in which B12 and folate metabolism overlap. Energy Reactions Metabolism Develop a basic understanding of some of the fundamental concepts of metabolism Biology Mad.
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