1. Preface - emfadr

simplicitynormalUrban and Civil

Nov 16, 2013 (3 years and 11 months ago)

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Innovative Economy




European Union

National Cohesion Strategy

European Fund for
Regional Development




Project co
-
funded by the European Union under the European F
und

for Regional
Development and Operational Program Innovative Economy



Composite Screens of Electric Field

ADR Technology

Technological expertise of the composites impact on the frequency screening
range and technological aptitude





1. Preface

Human exp
osure to the effects of the electromagnetic field is not a new problem.
However the rapid and uncontrolled increase
are

electric energy usage in 20
th

century coupled with the growth in field of electronics, IT, telecommunication,
and satellite

navigation a
s well as diagnostic and industrial devices brought us
not only to

analyze the
civilization danger
s but also to come out with methods to
screen the electromagnetic radiation.

The alarming American publication implies that the ‘electromagnetic smog is a
cau
se of many
civilization i
llnesses

such as circulation diseases, cancer, diabetes
and affects us much more than the changes in our lifestyle change.

[s. Milham, Medical Hypotheses 74(2010)337, Historical evidence

that electrification
caused the 20
th

centur
y epidemic of “diseases of civilization”]


The negative impact that the electromagnetic radiation (EMR) has on a
human body is mainly the fact that it interferes with its basic vital
functions.

The electric currents in the human body are one of the normal

vital
functions. The nerve signals are based on electric
impulses;

many

biochemical
reactions such as
digestion or b
rain activity are a result of
electric processes.

It is not a surprise that a
long
-
term

exposure to electric fields, even of a small
strength, can make us feel unwell.
[Establishing a Dialogue on Risks from
Electromagnetic Fields, Word Health Organization, Radiation and
Environmental Health

Department of the Human Environment, Geneva, Switze
rland 2002]

During the last

three decades the interest in the negative biological impact of the
electrical, magnetic and electromagnetic fields has raised amongst t
he scientists
and the international
organizations

(
World H
ealth Organization, Internationa
l

Commission on Non
-
Ionizing Radiation Protection
)
, that’s when the need for screening
arouse.








Prof. dr hab. Bozena Hilczer

A material that is supposed to absorb EMR must comply with the following:

Sci. 44(2009)3917, Polymeric nanocomposites for electromagnetic wave
absorption
):

i)

It’s impedance must be suitable with the impedance of the

medium
where the incident wave diverges (to limit the reflection in best
possible way)
,

ii)

The material needs to absorb

the EMR to the biggest degree within its
capacity, it means that it needs to have significant dielectric losses or
magnetic losses or, in the best case, dielectric losses and magnetic
losses.


Composites
-

multiphase systems are the modern screening materi
als. In a
process of integrating of
numerous
mono
-
functional
phases within one
material, we can get a multi
-
functional material of not only a small density
but also carrying the functions suited for the applying needs.

The topological
composition of the
functional extenders has an important role while planning
the properties of composites.

One of the newest
concepts of

the materials engineering is to use nano
-
particles of functional materials as extenders
. Thanks to the reduced linear
size
of such

nano
-
pa
rticles

have a big ratio
of the

area to
its

perimeter
meaning that they have a large number of active atoms on its surface.


The composites are a modern approach to
the planning of the EMR
screens,
because

of

the selection, perimeter ratios

and the way the
component phases are connected, we can design screens with a desired
frequency and efficiency of screening. When designing one should:

i)

Select

a functional ex
tender/extenders to ensure its functionality in
the
simplest

or easiest to impleme
nt composite architecture

ii)

Aim

to ensure compatibility between the extender and the composite
matrix

iii)

Apply

the lowest possible concentration of functional extenders, so
the disturbance caused by them is the smallest.


B
asic concept of the ADR TECHNOLOGY
,

el
ectromagnetic radiation field

screen
is to employ dielectric water absorption. The water is “captured” in a
dielectric

matrix in a form of
micro
-
drops, nano
-
drops and the water joined
in a network of crystalline salt forming hydrates. That makes this scree
n a
composite.

There are

several

t
ypes of screens that employ the ADR

TECHNOLOGY
screening fields ranging from an extremely low frequency electric fields to
radio frequencies up to 1 GHz. They are:
ceramic matrix screens such as
ADR TEX

(3 options)

ADR MAT

screens, ADR SOL and ADR PRIMER
ELECTRO PROTECT

(active impregnating material)

specimens;
high
frequency electromagnetic radiation screens

(developed in 3 versions on a
lab
oratory

scale)
.

The electric field sc
reens that are used commonly employ

conductiv
e
materials. They consist of foil or metallic net,
conductive composites or glass

or mate
rials with woven metal wires with
micron

diameters. These screens
are expensive, stiff and need to be grounded. The ADR TECHNOLOGY
materials do not require grounding, besides they are soft, light and they can
be easily fitted around the screened object.

2. OPINION ON INNOVATIVENESS

OF ADR TECHN
OLOGY SCREENS

The multiphase systems are a modern approach to designing

of

the
EMR screens
, because by selecting of the component phases of the
composite