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3.2. For questions 1-13, read the text below. Use the word given in capitals at the end of the lines to form a word that fits in the same line. Neutron Scattering

Neutron scattering from materials allows scientists to (1)_________ the structure and (2)____________ of materials down to atomic (3) _______ scales. Materials can be studies that are of interest to scientists in many fields including materials science and engineering, physics, chemistry, earth science and biology. Because neutrons are (4) _________ they can penetrate deeply into materials and it is possible to obtain the bulk properties of large samples, or to scan at (5) ________ for the residual stress in engineering components to ensure they will perform safely in operation. It is also possible by low-angle (6) __________ to explore the properties of surfaces, buried interfaces and (7) ________ layered structures. The structure of membranes and materials of biological (8) ___________ can also be determined. The magnetic moment of the neutron allows (9)______ of magnetic properties and highly correlated systems.

Since the 1950s many hundreds of neutron scattering experiments have been carried out at the NRU reactor at Chalk River, solving (10) _________ problems for industry sometimes with substantial economic impact and pushing back the frontiers of human (11) ________ of the world around us. Those experiments have contributed to the (12) _________ of many hundreds of highly qualified people across the spectrum of science. The NRC Canadian Neutron Beam Centre enjoys a strong international reputation, and connects Canadian scientists to international (13) __________ with over a 100 institutions in more than 20 countries during a typical five-year period.

EXPLORATION

DYNAMIC

LONG

CHARGE

DEEP

REFLECT

synthesis

SIGNIFICANT

STUDY

PRACTICE

UNDERSTAND

EDUCATE

collaborate

3.3. Read the text below and fill in the gaps with a suitable word (verb, preposition, conjunction or article) Materials Science and Engineering

The high penetration depth and characteristic wavelength of neutrons make neutrons well suited (1) ___ investigations of materials. Specimens can (2) ____ studied (3) ___ temperatures as high as 2000°C or as low as 1.5 K (-272°C). Specimens can also be studied under tensile and compressive loads ((4) ___ to 45 kN), for standard dog-bone specimens as (5) ___ as u-bends and compact tension specimens. It is possible to study specimens under load and at elevated temperatures (up to 550°C).

Other environments (6) ___ as electro-chemical potential and hostile environments have been developed. We also have the ability to examine radioactive samples. We develop new environments to meet user needs, for example (7) ___ furnace for determining crystallographic texture at elevated temperatures is currently (8) _____ development, as is an in-situ welding system.

In most cases, measurements can be made non-destructively, leaving the specimen intact for subsequent measurement (9) ____ other techniques. Special surface preparation is typically (10) ___ required. Due to the high penetration depth of neutrons, it is relatively easy to create a variety of specimen environments for in-situ experiments.