|
Premium 5
Premium 6
Premium Domains
Premium 2
Premium 3
LLLLL.com
LLLLL.com 2
LLLLL.com 3
Premium 4
Rare domains
cities_realestate
Similar Websites
education_sites
entertainment_sites
games
misc_sites
LLLL.com Site
Acronym 2
Acronym 4
Acronym 5
Acronym 6
Acronym 7
Acronym 8
Acronym 9
Acronym 10
Acronym 3
Brandable sites
Pin Yin sites
service_sites
technology
Acronym sites
Payment Options
About Our Office
| |
BFRP: Boron Fibre-reinforced plastic
A fibre-reinforced plastic (FRP) (also Fibre-reinforced polymer) is a
composite material comprising a polymer matrix reinforced with fibres. The
fibers are usually fiberglass, carbon, or aramid, while the polymer is usually
an epoxy, vinylester or polyester thermosetting plastic. FRPs are commonly used
in the aerospace, automotive, marine, and construction industries.
Boron (IPA: /ˈbɔːrɒn/) is a chemical element with atomic number 5 and the
chemical symbol B. A trivalent compound containing boron occurs abundantly in
the ore borax. Boron is never found free in nature, and is a non-metal.
Several allotropes of boron exist; amorphous boron is a brown powder, though
crystalline boron is black, hard (9.3 on Mohs' scale), and a weak conductor at
room temperature.
Elemental boron is used as a dopant in the semiconductor industry, while boron
compounds play important roles as light structural materials, nontoxic
insecticides and preservatives, and reagents for chemical synthesis.
Boron is an essential plant nutrient, although soil concentrations of > 1.0 ppm
can cause marginal and tip necrosis in leaves as well as poor overall growth
performance. Levels as low as 0.8 ppm can cause these same symptoms to appear in
plants particularly sensitive to boron in the soil. Nearly all plants, even
those somewhat tolerant of boron in the soil, will show at least some symptoms
of boron toxicity when boron in the soil is greater than 1.8 ppm. When boron in
the soil exceeds 2.0 ppm, few plants will perform well. Plants sensitive to
boron in the soil may not survive. When boron levels in plant tissue exceed 200
ppm symptoms of boron toxicity are likely to appear. As an ultratrace element,
boron is necessary for the optimal health of animals, though its physiological
role in animals is poorly understood.
Characteristics
Brown amorphous boron is a product of certain chemical reactions. It contains
boron atoms randomly bonded to each other without long range order.
Crystalline boron, a very hard black material with a high melting point, exists
in many polymorphs. Two rhombohedral forms, α-boron and β-boron containing 12
and 106.7 atoms in the rhombohedral unit cell respectively, and 50-atom
tetragonal boron are the three most characterised crystalline forms.
Optical characteristics of crystalline/elemental boron include the transmittance
of infrared light. At standard temperatures, elemental boron is a poor
electrical conductor, but is a good electrical conductor at high temperatures.
Chemically boron is electron-deficient, possessing a vacant p-orbital. It is an
electrophile. Compounds of boron often behave as Lewis acids, readily bonding
with electron-rich substances to compensate for boron's electron deficiency. The
reactions of boron are dominated by such requirement for electrons. Also, boron
is the least electronegative non-metal, meaning that it is usually oxidized
(loses electrons) in reactions.
Boron is also similar to carbon with its capability to form stable covalently
bonded molecular networks.
Applications
In automobiles: it is proposed that by reacting water with the element, hydrogen
could be produced to be burnt in an internal combustion engine or fed to a fuel
cell to generate electricity.
10B and 11B NMR spectroscopy
Both 10B (18.8 percent) and 11B (81.2 percent) possess nuclear spin; that of
boron-10 has a value of 3 and that of boron-11, 3/2. These isotopes are,
therefore, of use in nuclear magnetic resonance spectroscopy; and spectrometers
specially adapted to detecting the boron-11 nucleus are available commercially.
The boron-10 and boron-11 nuclei also cause splitting in the resonances of
attached nuclei.
B-10 depleted boron
The 10B isotope is good at capturing thermal neutrons from cosmic radiation. It
then undergoes fission - producing a gamma ray, an alpha particle, and a lithium
ion. When this happens inside of an integrated circuit, the fission products may
then dump charge into nearby chip structures, causing data loss (bit flipping,
or single event upset). In critical semiconductor designs, depleted
boron—consisting almost entirely of 11B—is used to avoid this effect, as one of
radiation hardening measures. 11B is a by-product of the nuclear industry.
11boron is also a candidate as a fuel for aneutronic fusion.
B-10 enriched boron
The 10B isotope is good at capturing thermal neutrons, and this quality has been
used in both radiation shielding and in boron neutron capture therapy where a
tumor is treated with a compound containing 10B is attached to a tissue, and the
patient treated with a relatively low dose of thermal neutrons which go on to
cause energetic and short range alpha radiation in the tissue treated with the
boron isotope.
In nuclear reactors, 10B is used for reactivity control and in emergency
shutdown systems. It can serve either function in the form of borosilicate rods
or as boric acid. In pressurized water reactors, boric acid is added to the
reactor coolant when the plant is shut down for refueling. It is then slowly
filtered out over many months as fissile material is used up and the fuel
becomes less reactive.
In future manned interplanetary spacecraft, 10B has a theoretical role as
structural material (as boron fibers or BN nanotube material) which also would
serve a special role in the radiation shield. One of the difficulties in dealing
with cosmic rays which are mostly high energy protons, is that some secondary
radiation from interaction of cosmic rays and spacecraft structural materials,
is high energy spallation neutrons. Such neutrons can be moderated by materials
high in light elements such as structural polyethylene, but the moderated
neutrons continue to be a radiation hazard unless actively absorbed in a way
which dumps the absorption energy in the shielding, far away from biological
systems. Among light elements that absorb thermal neutrons, 6Li and 10B appear
as potential spacecraft structural materials able to do double duty in this
regard.
Market trend
Estimated global consumption of boron rose to a record 1.8 million tonnes of
B2O3 in 2005 following a period of strong growth in demand from Asia, Europe and
North America. Boron mining and refining capacities are considered to be
adequate to meet expected levels of growth through the next decade. The form in
which boron is consumed has changed in recent years. The use of beneficiated
ores like colemanite has declined following concerns over arsenic content.
Consumers have moved towards the use of refined borates or boric acid that have
a lower pollutant content.
Increasing demand for boric acid has led a number of producers to invest in
additional capacity. Eti Mine opened a new 100,000 tonnes per year capacity
boric acid plant at Emet in 2003. Rio Tinto increased the capacity of its Boron
plant from 260,000 tonnes per year in 2003 to 310,000 tonnes per year by May
2005, with plans to grow this to 366,000 tonnes per year in 2006.
Chinese boron producers have been unable to meet rapidly growing demand for high
quality borates. This has led to imports of disodium tetraborate growing by a
hundredfold between 2000 and 2005 and boric acid imports increasing by 28% per
year over the same period.
The rise in global demand has been driven by high rates of growth in fiberglass
and borosilicate production. A rapid increase in the manufacture of
reinforcement-grade fiberglass in Asia with a consequent increase in demand for
borates has offset the development of boron-free reinforcement-grade fiberglass
in Europe and the USA. The recent rises in energy prices can be expected to lead
to greater use of insulation-grade fiberglass, with consequent growth in the use
of boron.
Roskill Consulting Group forecasts that world demand for boron will grow by 3.4%
per year to reach 21 million tonnes by 2010. The highest growth in demand is
expected to be in Asia where demand could rise by an average 5.7% per year
RuneScape is a Java-based
MMORPG operated by Jagex Ltd. With over nine million active free accounts and
more than one million paid member accounts, RuneScape is rated among the most
popular online games in the world. More than five million unique players access
their accounts to play RuneScape at least once per month. RuneScape offers both
free and subscription content and is designed to be accessible from any location
with an Internet connection and to run in an ordinary web browser without
straining system resources. One of the best website that discussed various
gamers' issues is IJFG.com IJFG.COM
Internet Junction For Gamers Internet Junction
For Gamers, Runescape Market and More IJFG.COM This site has Jokes, Pranks, Runescape and other cool games at IJFG.COM. RuneScape is set in a medieval
fantasy world, similar to "Guild Wars" or "EverQuest", where players control
character representations of themselves. As with most massive multiplayer online roleplaying games (MMORPG), there is no overall objective or end to the game.
Players explore, form alliances, perform optional tasks, and complete quests for
rewards and to build character's skills.
Internet Junction For Gamers, Runescape Market and More. IJFG.com IJFG.com
RuneScape takes place in the fantasy-themed realm of Gielinor, which is divided
into several different kingdoms, regions, and areas. Players can travel
throughout the gaming world on foot, by using magical teleportation spells or
devices, or mechanical means of transportation. Each region offers different
types of monsters, materials, and quests to challenge players. Players are shown
on the screen as customisable avatars. They set their own goals and objectives,
deciding which of the available activities to pursue. There is no linear path
that must be followed. Players can engage in combat with other players or with
monsters, complete quests, or increase their experience in any of the available
skills. Players interact with each other through trading, chatting, or playing
combative or cooperative mini-games.
Internet Junction For Gamers, Runescape Market and More IJFG.COM
IJFG.com
Contact Information
Call our office today to set up an appointment. Learn more about how we can
help you, and learn more about the other services that we can offer you. All
messages we receive will be answered as soon as possible. We look forward to
hearing from you.
- Electronic mail
- General Information:
| |
|
