Researchers find the strongest natural material in the world

The tooth of a limpet, this marine gastropod with a conical shell, is nothing less than the strongest biological material known to date, reveals a new study.

So far, spider silk was considered the strongest natural material in the world (read "soon The body armor products spider silk?" On the Figaro), stronger than steel and kevlar. But spider silk has been dethroned by a new biological material even stronger: the teeth of limpets, these marine gastropods have a conical shell. A discovery made by British scientists from the University of Portsmouth.

In fact, the strength of its teeth is valuable for limpet: it is thanks to them that the limpet can "shred" effectively the surface of the rocks, in order to remove the algae to feed.

In reaching the conclusion that the teeth of the patella is the strongest biological structures in the world, professor of engineering Asa Barber (University of Portsmouth. UK) and colleagues analyzed the mechanical behavior of teeth limpet to using an atomic force microscope, a tool to visualize the surface topography of a sample to the nanometer scale.

In this work, these scientists discovered the secret of solidity teeth limpet: the presence in them of goethite, a mineral that develops gradually as the limpet grows.

This discovery could enable the development of new superhard materials. Indeed, by copying the fibrous tooth structure limpets, it might well be possible to design very solid structures used in the manufacture of cars, aircraft or boat hulls.

This work was published February 18, 2015 in the journal Interface, entitled "Extreme strength Observed in limpet teeth".

Share:

Read More

Scaffolding, the practical guide : Types, Materials, Standards

Need to intervene in height: a gutter cleaning, repainting ceiling or exterior wall, trimming the hedge? The scaffold is the ideal solution. Must still choose the right scaffolding model ...
Types of scaffolding: mobile or fixed?
Scaffolding is a temporary structure made of tubular, usually metal, supporting floors and allowing access to working areas at height. There are two main types of scaffolding: mobile and fixed.
Mobile scaffolding: ideal for small sites
The mobile scaffolding is often used by individuals for the yards of a few days. It can also be used by some artisans like painters.
There are different kinds of mobile scaffolds:
mobile scaffold  : easy, it can be moved easily from one place to another,
folding scaffolding  : very little space for storage, it is also easy to assemble,
scaffolding staircase  : suitable for level differences, this type of scaffold is ideal for stairs, it can be folding or rolling.

Fixed scaffolding: for large construction sites
The fixed scaffold is a facility that aims to stay in one place for several weeks. We find this type of scaffolding on the facades of large city buildings. There are three types of scaffolding like this: the fixed scaffolding is the classic version of the fixed scaffolding, it is mainly for professional use and up to 12 meters high. The suspended scaffold , steering wheel or console, is intended for specific projects where a fixed scaffold may not be installed. The custom scaffolding , made ​​for special projects must respect the regulations in force.
Scaffolding materials: a wide selection
Scaffolds exist in several materials, each with the qualities and drawbacks: the steel scaffold is the most robust. The aluminum scaffold is the lightest and most fre. The scaffold fiber glass is insulating and aesthetic. The bamboo scaffolding is the greenest.
Features of scaffolding: standards and dimensions
Scaffolding must have certain characteristics that make it safe. it must meet certain standards to certify the quality of the material used. All scaffolding element has a standard specific to it and to which it can attach. He must have dimensions suitable for the construction project, the proposed maximum load, the physical setting, etc.

Safety on scaffolding: regulation
The use of scaffolding is essential in the construction sector. Despite regulations to prevent risks and ensure the safety of responders, scaffolding work are still the major cause of serious accidents on construction sites including the scaffold fall .
Some safety precautions have been put in place for the protection of the scaffolding , including side protection (guardrails, solid walls, wood or metal) and devices to stop the free fall of a body on less than one meter (safety harnesses and fall protection net, etc.).
Mounting the scaffold: Tea, console, disassembly ...
For better protection of the user, certain precautions and instructions must be observed when mounting and dismantling the scaffolding and its components: components of the scaffolding (tubes and feet), scaffold platform , scaffolding bracket .
Other ways to work at heights: ladder, ladder
Several other facilities outside scaffolding, allow you to work at heights:
the scale , which provides access to a height of up to 12 m: right scale , double ladder , extension ladder , telescopic ladder or articulated ladder ,
the stool , household item allowing access at lower heights to 3 m,
the individual platform , the ladder in industrial design,
the lifter plate , the hoists , for raising, not the person, but the materials.
Scaffolding Buying Guide
Buy a scaffold is not so simple, because you have to consider many criteria: working height, specific use of scaffolding, frequency of use, requirements, environmental constraints. Besides buying a scaffold, others more economic solutions exist: buy a used scaffolding or scaffolding rental .

Share:

Read More