|
A choice of three detectors is offered –
two types of photomultiplier and an avalanche
photodiode (APD); the latter offers improved sensitivity,
mainly to longer wavelengths e.g. the red of a
He-Ne laser. A second detector can be mounted
at a fixed angle of 900 if required. Mounts can
be tailored to suit virtually any type of laser,
the most popular being solid state DPSS (usually
532nm) or tuneable argon ion devices.
A variety of glass or quartz
cells can be accommodated within the sample holder
which is surrounded by refractive index matching
fluid contained in the ultra-high quality, temperature
controlled vat. Purity of the fluid is ensured
by the recirculating filtration system. A similar
accessory is available for filtering the sample
solution / suspension, especially for SLS applications
or when working with very small particles in DLS.
The BI-200SM has been designed for ease of use
and, for an instrument of this kind, offers unmatched
ease of alignment and maintenance. Brookhaven’s
BI-IST Alignment Software aids this process, providing
easy, automatic testing procedures which can be
used as a routine check on performance or following
maintenance operations.
Applications of BI-200SM based light scattering
systems are many and varied. They include submicron
particle size distribution analysis of colloids,
micelles, emulsions etc., study of nucleation,
crystallisation and aggregation processes, determination
of molecular weight, radius of gyration and second
virial coefficient of polymers in solution.
For SLS applications in which
the specific refractive index increment as a function
of polymer concentration (dn/dc) is required,
the Brookhaven BI-DNDC
is the ideal complement to a BI-200SM system.
Software for light scattering applications is
listed under the BI-9000AT
Correlator section.
|
