Light Wavelength
Light Wavelength - Related Videos
02:32
The de Broglie Wavelength
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2020
In the macroscopic world, objects that are large enough to be seen by the naked eye follow the rules of classical physics. A billiard ball moving on a table will behave like a particle; it will continue traveling in a straight line unless it collides with another ball, or it is acted on by some other force, such as friction. The ball has a well-defined position and velocity or well-defined momentum, p = mv, which is defined by mass m and velocity v at any given moment. This is the typical...
10:32
Sample Preparation and Transfer Protocol for In-Vacuum Long-Wavelength Crystallography on Beamline I23 at Diamond Light Source
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Cited by 2 •
2021
Here, we present a protocol for cryogenic sample preparation and transfer of crystals into the vacuum endstation on beamline I23 at Diamond Light Source, for long-wavelength macromolecular X-ray crystallography experiments.
08:16
Method for the Assessment of Effects of a Range of Wavelengths and Intensities of Red/near-infrared Light Therapy on Oxidative Stress In Vitro
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Cited by 11 •
2015
Non-coherent Xenon light was passed through narrow-band interference and neutral density filters to deliver light of varying wavelength and intensity to cultured cells. This protocol was used to assess the effects of red/near-infrared light therapy on production of reactive species in vitro: no effects were observed using the tested parameters.
01:33
Synergistic Photobiomodulation with a Dual-Wavelength Laser in an In Vitro Disease Model
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2025
Divide the transwell system into five groups that undergo various treatments.The first group serves as the control and consists of a co-culture of neuroblastoma and microglia cells.In the second group, treat the co-culturer with fibrillar β-amyloid (fAβ) alone. fAβ induces damage in neuroblastoma cells.In the third group, treat neuroblastoma cells with an 808-nanometer laser, then co-culture them with untreated microglia.The laser reduces oxidative stress, improving neuronal survival.In the...
02:12
The Wave Nature of Light
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2020
The nature of light has been a subject of inquiry since antiquity. In the seventeenth century, Isaac Newton performed experiments with lenses and prisms and was able to demonstrate that white light consists of the individual colors of the rainbow combined together. Newton explained his optics findings in terms of a "corpuscular" view of light, in which light was composed of streams of extremely tiny particles traveling at high speeds according to Newton's laws of motion. Others in the...
FAQs
Changing the wavelength changes both frequency and photon energy: shorter wavelengths correspond to higher values, whereas longer wavelengths correspond to lower values. A molecule can absorb the incident light when the photon energy matches an allowed transition between its energy levels. This matching condition determines which portions of a spectrum carry chemical information and helps explain selective absorption.
Different wavelength regions can probe different molecular motions or electronic changes. Absorption may arise from electronic, vibrational, or rotational transitions, and each produces characteristic spectral information. The resulting pattern is more informative than intensity alone because the positions of absorbed wavelengths reflect the energy-level structure of the molecule, supporting identification and structural investigation.
Method selection depends on the type of molecular information required. Ultraviolet-visible spectroscopy uses wavelength-dependent absorption for chemical analysis, including concentration measurements and reaction monitoring, while infrared spectroscopy supports identification and investigation of molecular structure. Comparing these approaches shows why no single wavelength region provides every kind of chemical evidence.
In ultraviolet-visible analysis, chemists examine how a substance absorbs selected wavelengths and relate that wavelength-dependent response to concentration. The method can also follow changes while a reaction proceeds, making it useful for monitoring reactions rather than only characterizing a final sample. The measured spectral response therefore connects molecular absorption behavior with quantitative chemical analysis.
An unknown can be examined through its characteristic spectrum, which records the wavelengths associated with its absorption. Matching the observed pattern to wavelength-dependent chemical behavior helps distinguish substances and can reveal structural information. Because electronic, vibrational, and rotational transitions contribute differently, the spectral pattern provides a chemical signature rather than a single yes-or-no measurement.
In materials research, wavelength-dependent measurements help investigate how materials interact with light and provide information relevant to their chemical behavior. For photochemical process design, choosing wavelengths that correspond to useful molecular transitions can influence which species absorb energy. This connection between wavelength, energy levels, and absorption helps researchers develop and study light-driven chemical processes.