hpea

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Contents
Windows
®
is a registered trademark of the Microsoft Corporation.
Copyright © Hansatech Instruments Ltd. 1996 - 2001.
 Introduction to Handy PEA
Continuous Excitation Fluorescence Measurements.
If a healthy leaf is suddenly illuminated after a period of darkness, a time-dependent fluorescence
induction (Kautsky Effect) is observed, the amplitude of which is proportional to the incident light level.
Typically, illumination of a healthy leaf after 10 - 30 minutes dark adaptation results in an immediate rise
to level (O or Fo) followed by a rapid polyphasic rise to a peak level (P or Fp). If sufficient light is used
the primary electron acceptor from PSII (Qa) becomes fully reduced, transiently inhibiting
photochemistry. In such circumstances the maximum fluorescence level is observed (Fm). The time to
reach the fluorescence peak is very short (500 msec). Hence it is useful to plot the fluorescence rise on a
logarithmic scale to view the polyphasic kinetic.
In addition to the
the Handy PEA offers the flexibility to analyse
intermediate fluorescence data points at specific times within the fluorescence induction for further
analysis. The analysis of these intermediate data points forms the basis of
(Strasser R.J.,
Srivasatava A. and Govindjee,1995 Polyphasic chlorophyll a fluorescence transient in plants and
cyanobacteria, Photochemistry and Photobiology, 61, 32-34.) more commonly now referred to as the JIP
test.
Windows
®
is a registered trademark of the Microsoft Corporation.
Copyright © Hansatech Instruments Ltd. 1996 - 2001.
 Introduction to Handy PEA
General Information.
Select a link from the following:
Windows
®
is a registered trademark of the Microsoft Corporation.
Copyright © Hansatech Instruments Ltd. 1996 - 2001.
 Parameters Measured
Fo - fluorescence level when plastoquinone electron acceptor pool (Qa) is fully
oxidised.
Fm - fluorescence level when Qa is transiently fully reduced.
Fv - variable fluorescence (Fm-Fo).
Fv/Fm - maximum quantum efficiency of photosystem II.
Tfm - time at which Fm occurs.
Area - area over the curve between Fo and Fm, relates to the pool size of PSII electron transport
acceptors.
OJIP analysis (Strasser R.J., Srivasatava A. and Govindjee,1995 Polyphasic chlorophyll a
fluorescence transient in plants and cyanobacteria, Photochemistry and Photobiology, 61, 32-34.).
Follow this link for information on the
Windows
®
is a registered trademark of the Microsoft Corporation.
Copyright © Hansatech Instruments Ltd. 1996 -2001.
  Technical Specifications
Dimensions - 170 x 85 x 40mm
Weight - 565gms
Operating Conditions - 0 - 40°C Non condensing humidity.
Battery - 3 rechargeable (Ni-MH) 3.6V 1.8Ahr.
Battery Life - Typically 8 - 9 hours when performing 1 second recordings at 120 measurements/hr.
Integral switch mode battery charger 8-13.5V input (nominal 12V input)
Display - 8 line x 20 character LCD display.
Illumination -
Focused array of ultra-bright red LED's with NIR short pass cut-off filters.
Peak wavelength 650 nm. Spectral-line half width 22 nm.
Max. intensity at leaf surface >3000µmol m
-2
s
-1
.
Detector - Fast response PIN photodiode with RG9 long pass filter.
Electronics - 16 bit microprocessor, 12 bit resolution, A/D 10µsec acquisition rate, 8 bit DAC for
light source control, real time clock.
Record Length - 1 millisecond - 300 seconds
Memory - 512K battery backed RAM (sufficient for up to 1000 one second duration recordings with
full trace data).
In the interests of updating and improving our equipment Hansatech Instruments Ltd. reserve the right to
alter specifications without prior notice.
Windows
®
is a registered trademark of the Microsoft Corporation.
Copyright © Hansatech Instruments Ltd. 1996 -2001.
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