Diffractometer measurement of low-order powder reflexions

A compact high-resolution X-ray powder diffractometer

A new powder diffractometer operating in transmission mode is described. It can work as a rapid very compact instrument or as a high-resolution instrument, and the sample preparation is simplified. The incident beam optics create pure Cu Kα1 radiation, giving rise to peak widths of ∼0.1° in 2θ in compact form with a sample-to-detector minimum radius of 55 mm, reducing to peak widths of <0.05° i...

Building a high resolution total scattering powder diffractometer – upgrade of NPD at MLNSC

The neutron powder diffractometer NPD at the Manuel Lujan Neutron Scattering Center (MLNSC) at Los Alamos National Laboratory is the neutron powder diffractometer with the highest resolution in the United States. We are currently upgrading NPD by adding a large number of position-sensitive detectors in the backscattering position. The upgraded instrument will make it possible to collect data fr...

A two-circle powder diffractometer for synchrotron radiation on Station 2.3 at the SRS

Measuring Single Crystal Diffuse Neutron Scattering on the Wombat High Intensity Powder Diffractometer

Single crystal diffuse scattering was collected on the Wombat high-intensity powder diffractometer at the OPAL reactor at the Bragg Institute. The difficulty in measuring diffuse scattering comes from its relatively low intensity compared to the Bragg peaks, a factor of 10−10 smaller. Wombat allows collection of diffuse scattering due to its high intensity and large two-dimensional detector. Di...

Reflexions on energy balance.

Calorimetry is the basis of the science of nutrition, a statement I iirst saw as the title of a paper by the chief of the department of medicine at the Mayo Foundation (Wilder, 1959). Our science began when Lavoisier put a guinea pig into a calorimeter, measured the amount of ice melted and showed that this was quantitatively related to the amount of fixed air or carbon dioxide given off by the...