NM_e2_23

Steve Jobs introduced the first "smart phone" in 2007. Which sensor was not included?

• ambient light sensors.
• proximity sensor.
• accelerometer sensor.
• magnetometer.

Nanoscale catalysts are attractive since

• their surface/volume ratio scales with 1/radius ^2.
• nanosize could lead to novel chemical properties.
• they are less toxic.
• their production is cheaper.

The resolution of an electron microscope is

• diffraction limited.
• limited by elastic interaction with the sample.
• limited by interaction volume size.
• is limited by the imperfect capacitive lenses.

Electrons kicked out from core orbits

• are the main source of secondary detector signal.
• create X ray emission, the source of secondary e detection.
• result backscattered electrons.
• used for composition analysis by EDS detector

Focused ion beam…

• is a technique to engineer surfaces at the atomic level.
• bombards the surface with ions which allow to mill atoms out.
• uses different principle of focusing than electron microscopes.
• has no pactical application.

Nanotechnology

• is a multidiciplinary field including physics, chemisty and biology.
• was overadvertised around 2000, but has no influence on science today.
• started with the realization Scanning Electron Microscope.
• focuses on objects which are smaller than 1μm.

The resolution of a Fourier transform infrared spectrometer depends on

• the maximal path length difference.
• the spectral width of the source.
• the sampling interval.
• the speed of the moving mirror.

X-ray absorption does NOT sensitive to

• the composition
• the local environment
• the charge state
• the mass number

The number of vibrational modes in a diatomic molecule is

• 3
• 2
• 1

GaAs is a valuable material for photonics because

• it has indirect band gap
• it has direct band gap
• emits blue light
• has large spin-orbit coupling