325 mJ and 46 ns 532 nm Q-switched Nd:YAG laser at 500 Hz

Bai

Micro & Optical Tech Letters

et al. 2021

An all-solid-state pulse width adjustable Nd:YAG nanosecond laser at 1064 nm is demonstrated based on the bidirectional voltage supplied Q-switched technology. Continuously adjustable pulse-width from 4.6 to 32.3 ns is generated in a linear cavity, which is laser diode side-pumped at 808 nm at 100 Hz repetition rate. With 27 ns Q-switch duration, the shortest pulse width of 4.6 ns with single pulse energy of 0.77 mJ and a near-Gaussian beam quality (M 2 < 1.6) is obtained. Our results suggest an approach to generating pulsewidth adjustable nanosecond lasers for applications in LIDAR.

Section: Discussionmentioning

confidence: 99%

A pulse‐width adjustable electro‐optic Q‐switched nanosecond laser oscillator

Bai

Micro & Optical Tech Letters

et al. 2021

“…Further characterization of the system revealed that phosphorylated IκB-α actually facilitated DNA exchange by NF-κB (Figure 15), a property that could contribute to its physiological role as a mediator of transcription of numerous cellular genes. 182…”

Section: Modified Ribosomes For Protein Tyrosine Phosphorylationmentioning

confidence: 99%

Expanding the Scope of Protein Synthesis Using Modified Ribosomes

Dedkova

Hecht

2019

J. Am. Chem. Soc.

The ribosome produces all of the proteins and many of the peptides present in cells. As a macromolecular complex comprised of both RNAs and proteins, it employs a constituent RNA to catalyze the formation of peptide bonds rapidly and with high fidelity. Thus the ribosome can be argued to represent the key link between the RNA World, in which RNAs were the primary catalysts, and present biological systems in which protein catalysts predominate. In spite of the well known phylogenetic conservation of ribosomal RNAs through evolutionary history, ribosomal RNAs can be altered readily when placed under suitable pressure, e.g. in the presence of antibiotics which bind to functionally critical regions of rRNAs. While the structures of rRNAs have been altered intentionally for decades to enable the study of their role(s) in the mechanism of peptide bond formation, it is remarkable that the purposeful alteration of rRNA structure to enable the elaboration of proteins and peptides containing non-canonical amino acids has occurred only recently. In this Perspective, we summarize the history of rRNA modifications, and demonstrate how the intentional modification of 23S rRNA in regions critical for peptide bond formation now enables the direct ribosomal incorporation of D-amino acids, β-amino acids, dipeptides and dipeptidomimetic analogues of the normal proteinogenic L-α-amino acids. While proteins containing metabolically important functional groups such as carbohydrates and phosphate groups are normally elaborated by the post-translational modification of nascent polypeptides, the use of modified ribosomes to produce such polymers directly is also discussed. Finally, we describe the elaboration of such modified proteins both in vitro and in bacterial cells, and suggest how such novel biomaterials may be exploited in future studies.

Micro & Optical Tech Letters

“…However, its beam quality ( M 2 = 2.5/3.2) is relatively poor due to its side‐pumped scheme. With a frequency doubling crystal, 32.5 mJ, 4.6 ns of 532 nm laser was obtained 13 …”

Section: Introductionmentioning

confidence: 99%

“…With a frequency doubling crystal, 32.5 mJ, 4.6 ns of 532 nm laser was obtained. 13 Thermal management is an essential issue for high energy laser. Longitudinal pumping is one of the most efficient configurations as it could match the mode of the pump beam to the resonant mode.…”

Section: Introductionmentioning

confidence: 99%

High energy LiDAR source for long distance, high resolution range imaging

Jiang

Yang

et al. 2020

Self Cite

High energy, high repetition rates laser with excellent beam quality are fundamental components for LiDAR. In particular, high pulse energy is benefit for long distance range imaging. Narrow pulse width and high repetition rates are benefit for high resolution and high refresh rate operation of LiDAR. However, increasing the laser repetition rates will cause the pulse energy decreasing and the pulse width expanding. In order to achieve the requirements at the same time, we propose a 885 nm laser diode end-pumped RTP Q-switched Nd:YAG laser. Pulse pumping scheme was used to avoid heat accumulation. With a master oscillator power amplifier (MOPA) system, 40.5 mJ, 7.5 ns of 1064 nm pulses were obtained at 2 kHz. The beam quality factor M 2 was measured as 1.60/1.51. Moreover, by frequency doubling with a LBO crystal, 16.4 mJ, 6.5 ns of 532 nm laser with the M 2 factor of 1.52 and 1.50 was obtained. The 1064 and 532 nm pulses are suitable for avalanche photodiode arrays LiDAR and streak tube imaging LiDAR, respectively. The laser system is shown to accomplish high stability from temperature of −10 C to 30 C and vibration frequency of 10 to 100 Hz.