Beamline Operation
Contents:
Part I: Experimental Hutch operation (Personnel safety system, PSS)
PART II: X-ray tomography experiment
(DATA Acquisition system, DAQ)
PART III: Data Processing &
Remote Backup
IMPORTANT: Before operating BL1.2W,
users must acknowledge this local regulation:
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To protect the radiation from the experimental hutch, user must be trained for Beamline Hutch Search and Secure and Breaking Security
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Operation of the beamline must only be undertaken by authorized person
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User must wear a provided radiation controlled badge at all time in the experimental hall
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User should not remain in the experimental hall during beam injection
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No food or drinks are allowed at the beamline station
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Users should clean up beamline on the last day of beamtime
HUTCH & PSS
PERSONNEL SAFETY SYSTEM (PSS)
PPS consist of electrical interlocks and mechanical barriers & locks that prevent personnel from entering beam enclosures and other areas in which the potential for high radiation exposure exists so that they are protected against prompt radiation. The interlocks also serve to shut off the radiation source if any of the interlocked barriers into beam enclosures are breached.
Search & Secure the hutch
Before beam is allowed into an experimental enclosure, a search & secure procedure must be performed by the user to ensure that no individual is in the experimental station during beam transmission through the experimental beamline.
Breaking the security (Emergency exit)
In the unlikely case that somebody is accidentally locked inside an experimental station after a search procedure has
been completed. Emergency exit procedure will break the
security and reset the search & secure.
To protect the radiation from the experimental hutch, user must be trained for Beamline Hutch Search and Secure and Breaking Security
Experiment
Sample Preparation
Fixation
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Using formaldehyde (FA) or glutaraldehyde (GA)
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Typical 4% is used, for 12 hours or more
Dehydration & immerse
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70% EtOH, 2 hours
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80% EtOH, 2 hours
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90% EtOH, 2 hours
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100% EtOH, 2 hours
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Immerse inHexamethyldisilazane (HMDS), 2 hours
Air dry
Make or become dry through contact with unheated air minimum 2 hours
Handling & Mounting
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Available specimen carrier and Goniometer head
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Sample holder options at BL1.2W
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45° Mount, Ø = 6 mm, aluminum
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45° and 90° Mount, Ø = 6 mm, aluminum
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90° Mount , Ø = 6 mm , aluminum
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Ø = 6 mm , aluminum
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Ø = 1.5 mm, brass
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Handling and mounting use container density less than sample density. Often used are small polystyrene tubes
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In order to mount the sample to sample holder use transparent glue, wax or 2-side tape
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User should make sure that the sample is stabilized to the sample holder other wise sample displacement during data collection will affect the CT reconstruction
Other apparatus that may be needed in sample preparation e.g. heat gun, glue gun, and stereo microscope, are also provided at the Sample Station
DATA COLLECTION
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(Filtered) white beam
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Motor control
DATA PROCESSING
Quantitative analysis in tomography is based on binary images. At a given threshold, t generated by applying a threshold to the histogram of reconstructed slices. Binary images is resulting in binary image
