Zinc oxide is used to produce ______________.
A. shampoo
B. sunscreen
C. food
D. weapon
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Ethicsinnanotechnologyofteninvolves:
A. thedefinitionofnanotechnology
B. concerningthescientificconsequencesofnanotechnology
C. concerningitsbearingoncultural,social,economic,environmentalandpoliticalmatters
D. safetyconcerns
Nanomaterialsare at nanoscale, characterizedwith:
A. arelativelylargersurfacearea
B. quantum effect, quantum size effect, quantum tunneling effect, small size effect
C. flexibledimensions
D. easytodegrade
Based on the synthesis process and path, there are 4mainapproaches used innanotechnology. They are:
A. bottom-upapproach
B. top-downapproach
C. functionalapproach
D. biomimeticapproach
Whichofthefollowingstatementsaboutbottom-upapproachesinnanotechnologyarecorrect?
A. DNAnanotechnologyutilizesthespecificityofWatson–Crickbasepairingtoconstructwell-definedstructuresoutofDNA&othernucleicacids(e.g.DNAorigami).
B. Approaches from the field of "classical" chemical synthesis (inorganic & organic synthesis) also aim at designing molecules with well-defined shape (e.g. bis-peptides).
C. More generally, molecular self-assembly seeks to use concepts of supramolecular chemistry, & molecular recognition in particular, to cause single-molecule components to automatically arrange themselves into some useful conformation.
D. Atomic force microscope tips can be used as a nanoscale "write head" to deposit a chemical upon a surface in a desired pattern in a process called 'dip pen nanolithography'. This technique fits into the larger subfield of nanolithography. Molecular beam epitaxy allows for bottom up assemblies of materials, most notably semiconductor materials commonly used in chip & computing applications, stacks, gating, & nanowire lasers.
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