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Posts Tagged ‘chemistry’

Timeline of biology and organic chemistry

11/07/2018 Σχολιάστε
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Χημικοί έχουν ανακαλύψει μια ευλογοφανή συνταγή για την πρώιμη ζωή στη Γη

02/07/2018 Σχολιάστε

Επιστήμη

11.1.2018

Χημικοί, στο Ερευνητικό Ινστιτούτο Scripps (TSRI) έχουν αναπτύξει μια συναρπαστική νέα θεωρία για το πώς πρέπει να έχει αρχίσει η ζωή στη Γη. Τα πειράματά τους, που περιγράφονται στο περιοδικό Nature Communications, δείχνουν ότι βασικές χημικές αντιδράσεις που υποστηρίζουν την ζωή σήμερα θα μπορούσαν να έχουν πραγματοποιηθεί με συστατικά που πιθανώς να ήταν παρόντα στον πλανήτη πριν από τέσσερα δισεκατομμύρια χρόνια.

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Making Sense of the Chemistry That Led to Life on Earth

24/06/2015 Σχολιάστε

 Gustave Caillebotte: Villers-sur-Mer - 1880

Gustave Caillebotte: Villers-sur-Mer – 1880

 

 

By NICHOLAS WADE, The New York Times, MAY 4, 2015

 

It was the actions of Jupiter and Saturn that quite inadvertently created life on Earth — not the gods of the Roman pantheon, but the giant planets, which once orbited much closer to the sun.

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RNA World 2.0

08/04/2015 Σχολιάστε

    © KEVIN HAND

 

Most scientists believe that ribonucleic acid played a key role in the origin of life on Earth, but the versatile molecule isn’t the whole story.

By Jef Akst | March 1, 2014

The ubiquity and diverse functionality of ribonucleic acid (RNA) in today’s world suggest that the information polymer could well have been the leading player early on in the establishment of life on Earth, and, in theory, it’s a logical basis for primitive life. One can readily imagine that RNA, as a catalytic molecule capable of serving as a template for its own replication, might have reproduced itself and grown exponentially in the primordial environment. Perhaps such an RNA-based proto–life-form even replicated with an appropriate level of fidelity to allow natural selection to begin directing its evolution.

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Five insights challenging science’s unshakable ‘truths’

06/01/2015 Σχολιάστε

 Methyl groups, which affect our genes, often come from what we eat.

Methyl groups, which affect our genes, often come from what we eat. Photograph: Science Photo Library

 

If you thought dying of loneliness was just an old wives’ tale, or that genetic inheritance is fixed – think again. Michael Brooks on science’s most unexpected findings

Michael Brooks, The Observer, Sunday 29 June 2014

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Ideas for Improving Science Education

05/03/2014 Σχολιάστε

IVΑNYI GRάNWALD, Bιla, In the Valley, c. 1900, Magyar Nemzeti Galιria, Budapest

 

 

· By Claudia Dreifus, The New York Times, September 2, 2013

If you could make one change to improve science education in the United States, what would it be? Science Times asked that question of 19 Americans — scientists, educators, students — with a stake in the answer. Their responses follow.

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The Big Squeeze

16/01/2014 Σχολιάστε

 

Photographs by A. Sharma, above right, and from top to bottom, at left, Jinfu Shu, R. E. Cohen and D. G. Isaak, M. Somayazulu and Yue Meng

 

The Carnegie Institution for Science can observe how organic substances, like oxalic acid dihydrate, right, react under pressure, born of a mission to study Earth’s interior. Diamond anvils, top left, were used on ferrous iron oxide, xenon and oxygen, forming different structures.

By KENNETH CHANG, The New York Times, December 16, 2013

WASHINGTON — In a recurring comic bit, David Letterman used to place household items — a plate of jelly doughnuts, a six-pack of beer — in an 80-ton hydraulic press, gleefully watching as the items squirted, exploded and disintegrated.

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Dan Shechtman: ‘Linus Pauling said I was talking nonsense’

24/01/2013 Σχολιάστε

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Ron Freeborn, Harbour – Kyrenia, Cyprus

 

The Israeli Nobel laureate discusses the discovery that caused a furore among fellow scientists

dan shechtman

Professor Dan Shechtman, who discovered quasicrystals, displays a model at his lab in Haifa, Israel. Photograph: David Blumenfeld

To stand your ground in the face of relentless criticism from a double Nobel prize-winning scientist takes a lot of guts. For engineer and materials scientist Dan Shechtman, however, years of self-belief in the face of the eminent Linus Pauling‘s criticisms led him to the ultimate accolade: his own Nobel prize.

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Αγνωστο είδος χημικού δεσμού

07/08/2012 Σχολιάστε

Βαγγέλης Πρατικάκης, ΤΟ ΒΗΜΑ 23.7.12

Ονομάζεται «κάθετος παραμαγνητικός δεσμός» και υπάρχει μόνο σε νεκρά άστρα

Αγνωστο είδος χημικού δεσμού

Οι κανόνες της Χημείας φαίνονται ότι αλλάζουν στους λευκούς νάνους, υπέρπυκνα κατάλοιπα νεκρών άστρων.

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On the Origin of chemical elements

26/11/2011 Σχολιάστε

By Kelly Oakes

| Scientific American

August 2, 2011

We take it for granted that there exists a periodic table with numerous elements (at last count, 118) from which we can construct the world around us. But when the universe began with a big bang, it started out with no elements at all.

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Chemistry as the Language of Life

10/11/2011 Σχολιάστε

By MARK HAY, The New York Times, 14.10.11

A coral rack on the reef at Votua village with a diver monitoring the corals. Insets show (top to bottom): the green seaweed Chlorodesmis in contact with a coral on the reef, the seaweed in contact on our experimental rack, and the effects on the coral (bleached and dead tissue) following 20 days of exposure to the seaweed.

Mark Hay; inset photos by Douglas RasherA coral rack on the reef at Votua Village with a diver monitoring the corals. Insets show (top to bottom): the green seaweed Chlorodesmis in contact with a coral on the reef, the seaweed on our experimental rack, and the effects on the coral (bleached and dead tissue) after 20 days of exposure to the seaweed.

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What is a name? For Chemists, Their fields’soul

09/08/2011 Σχολιάστε

By Carmen Drahl | Scientific American August 2, 2011

By 1992, the Soviet Union was formally dissolved, and the entire world’s political, economic, and military alliances were in the throes of transformation. But you could forgive officials at the International Union of Pure and Applied Chemistry (IUPAC) if they didn’t notice much of a difference.

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