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A cryo scanning transmission X-ray microscope, the cryo-STXM, has been designed and commissioned at the Canadian Light Source synchrotron. The instrument is designed to operate from 100 - 4000 eV (lambda = 12.4 - 0.31 nm). Users can insert a previously frozen sample, through a load lock, and rotate it plus minus 70 degrees in the beam to collect tomographic data sets. The sample can be maintained for extended periods at 92 K primarily to suppress radiation damage, and a pressure on the order of 10-9 Torr to suppress sample contamination. The achieved spatial resolution (30 nm) and spectral resolution (0.1 eV) are similar to other current soft X-ray STXMs, as demonstrated by measurements on known samples and test patterns. The data acquisition efficiency is significantly more favorable for both imaging and tomography. 2D images, 3D tomograms and 4D chemical maps of automotive hydrogen fuel cell thin sections are presented to demonstrate current performance and new capabilities, namely cryo-spectrotomography in the soft X-ray region., 56 pages

A new scanning transmission X-ray microscope (STXM) optimized for cryo-spectro-tomography with soft X-rays has been designed, built and commissioned at Canadian Light Source (CLS) beamline 10ID1 (130-2700 eV). It is controlled via a new python-based software package, pySTXM. A liquid N2 goniometer (Gatan 630, -80° to 80°), mounted on a computer controlled (x,y,Theta) tilt stage allows for spectro-tomographic measurements at cryogenic temperatures (-180°C) which reduces radiation damage. The CLS cryo-STXM is unique among the set of soft X-ray STXMs currently installed around the world. Details of the cryo-STXM design and examples of its performance will be presented.

This paper describes the creation and validation of a computer model of a liquid helium transfer line located at the Canadian Light Source (CLS) in Saskatoon, Canada. This line transfers liquid helium to a cryostat, which contains a superconducting radio frequency (RF) cavity, and requires precise pressure and level modulation to ensure proper RF control. A detailed mathematical model of the transfer line is created based on mass, momentum, and energy continuity along with pressure-volume-temperature relations. The model is discretized and solved, and model results are compared with experimental data taken from the actual cryostat at the CLS to validate of the simulation. The validated model is found to reasonably predict flow rates through the transfer line at the CLS from a process perspective.

This work includes the creation and validation of a computer model of a liquid helium cryostat located at the Canadian Light Source (CLS) in Saskatoon, Canada. This cryostat contains a superconducting radio frequency (RF) cavity, and requires careful pressure and level modulation to ensure proper RF control. A detailed mathematical model of the cryostat is generated based on gas and liquid mass balances for a boiling vessel, along with pressure–volume–temperature relations. The model is discretized and solved, and model results are compared with experimental data taken from the actual cryostat at the CLS to determine the accuracy of the simulation. The model is found to reasonably represent the cryostat at the CLS from a process perspective.

A new soft X-ray scanning transmission X-ray microscope (STXM) optimized for cryo spectro-tomography was designed and commissioned at the Canadian Light Source (CLS). The instrument was required to achieve ultra high vacuum and be compatible with in-situ plasma cleaning. It also required a scintillator detector, and the design of this detector had to evolve to meet these environmental requirements. The scintillator deposition technique, and the suppression of background by introduction of an edge filter are also presented.

The Canadian Light Source (CLS) is a third-generation synchrotron located inSaskatoon, Canada. A superconducting radio frequency (SRF) cavity contained in a 4.43 Kliquid helium I cryostat is used at the CLS to replenish energy loss in the electron beam. Adynamic simulation of this cryostat has been generated to examine pressure and levelfluctuations due to variations in heat loading or other system parameters. This simulatorhas led to some interesting observations in system behavior, which have been shown tooccur in the actual system as well. For example, mass rates of vaporization appear to dropas heat loading increases under certain conditions. Also, the relationship between pressureand SRF tuning characteristics is examined, and the abilities and limitations of thesimulator are presented.

Fast changing global markets demand that manufacturers quickly develop products that are simultaneously cost-effective and meet stakeholder needs. To survive in the hyper competitive environment of the information society, innovative product design is essential. However, it can be difficult for designers to identify whether the design is a “good” design before a product is manufactured and marketed. This paper develops a model to quantify the impor-tance of good design characteristics. Through the use of cluster-fuzzy inference algorithm, quantified design “goodness” weights are generated based on surveys of rank ordered “goodness” characteristics. The cluster-fuzzy weights are compared with weights obtained from statistical analysis and found to have similar trends, but provides better insight to the relationship with rest of the characteristics. A cluster-fuzzy approach is an effective tool to de-termine important design parameters in the early stages of design.

This work includes the creation of a computer model of the superconducting radio frequency cryostat located at the Canadian Light Source (CLS) in Saskatoon, Canada. This cryostat requires careful pressure and level modulation to ensure proper radio frequency control. A detailed mathematical model of the cryostat is generated based on gas and liquid mass balances for a boiling vessel, along with pressure–volume–temperature relations. Model results are compared with experimental data taken from the actual cryostat at the CLS to determine the accuracy of the simulation. Finally, cryostat performance is explored using the model, and it is demonstrated that there are no significant advantages in pressure modulation when reducing the level operating point, and in fact a reduction in operating level slightly increases the maximum value of pressure spikes due to heat loading.