Notes![what is notes.io? What is notes.io?](/theme/images/whatisnotesio.png)
![]() ![]() Notes - notes.io |
An all-fiber high-power erbium-doped fiber laser (EDFL) source generating optical pulses from 200 µs to 5 ms with a stable rectangular envelope for fractional photo-rejuvenation is proposed and experimentally demonstrated. A master oscillator power amplifier (MOPA) configuration composed of a master oscillator, an acousto-optic modulator (AOM), and a one-stage amplifier is designed and employed in the EDFL to serve as an efficient laser system with excellent output performance. To avoid multistage amplifiers, the master oscillator generates 1.5 W, and a Yb-free Er-doped large-mode-area (LMA) active fiber is used for a one-stage power amplifier. There are two benefits to this approach first, modulation of both pump and seed pulses is used to achieve clear rectangular shaped pulses without amplified spontaneous emission (ASE) growth; and second, there are no power limitations in the amplifier and undesirable 1 µm ASE compared to Er/Yb systems. We have reached 28.6 W of peak power with 26% slope efficiency limited only by available pump power, so the system can be easily scaled for achieving a higher peak power.The detection and discrimination of organic acids (OAs) is of great importance in the early diagnosis of specific diseases. In this study, we established an effective visual sensor array for the identification of OA. This is the first time, to our best knowledge, that metal ions were used to regulate the etching of silver triangular nanoprisms (AgTNPs) in an OA discrimination sensor array. The sensor array was based on the oxidation etching of AgTNPs by three metal ions (Mn2+, Pb2+, and Cr3+) and accelerated etching of AgTNPs by OA. The introduction of metal ions alone led to a slight wavelength shift of the AgTNPs colloid solution, signifying the incomplete etching of the AgTNPs. Nevertheless, when metal ions and OA were introduced simultaneously to the solution, a significant blueshift of the localized surface plasmon resonance peak was detected, and a color change of the AgTNPs was observed, which were the consequences of morphological transitions of the AgTNPs. The addition of different OA accelerated AgTNPs etching in varying degrees, generating diverse colorimetric response patterns (i.e., RGB variations) as "fingerprints" associated with each specific organic acid. Pattern recognition algorithms and neural network simulation were employed to further data analysis, indicating the outstanding discrimination capability of the provided array for eight OA at the 33 µM level. Moreover, excellent results of selective experiments as well as real samples tests demonstrate that our proposed method possesses great potential for practical applications.In this paper, an all-metal metasurface (MS), which can achieve high-efficient reflective circular-polarization conversion and multifunctional terahertz (THz) wavefront manipulation in an ultra-broadband frequency range, is proposed and investigated theoretically. The proposed all-metal MS consists of the periodic array of a gold vertical-split-ring (VSR) structure adhered on gold substrate. Numerical simulation results indicate that the proposed MS structure can convert the incident circular-polarization (CP) wave into its orthogonal component after reflection with a conversion coefficient over 95% from 0.8 to 1.65 THz (relative bandwidth of 68.3%). The full 2π phase shift of the proposed MS in this frequency range can be obtained by changing the rotation angle of the VSR structure along the wave propagation direction. As proof of concept for the multifunctional wavefront manipulation, anomalous reflection, reflective planar focusing, and vortex beam generation are numerically demonstrated based on the Pancharatnam-Berry (PB) phase principle. Our work can provide an effective method of enhancing the performance of reflective-type all-metal MS and show endless potential in wavefront manipulation and communication applications in THz and even optical region.In this paper, a 1064 nm pulsed laser source and a short-wave IR (SWIR) camera are used to measure the total system efficiency associated with a digital holography system in the off-axis image plane recording geometry. At a zero path-length difference between the signal and reference pulses, the measured total system efficiency (15.9%) is consistent with that previously obtained with a 532 nm continuous-wave laser source and a visible camera [Appl. Opt.58, G19 (2019)APOPAI0003-693510.1364/AO.58.000G19]. In addition, as a function of the temporal delay between the signal and reference pulses, the total system efficiency is accurately characterized by a component efficiency, which is formulated from the ambiguity function. Even with multimode behavior from the pulsed laser source and substantial dark current noise from the SWIR camera, the system performance is accurately characterized by the resulting ambiguity efficiency.We propose a method for diagnosis of cirrhosis and hepatocellular carcinoma (HCC) by using a terahertz (THz) metamaterial (MM) biosensor. The biosensor has a resonance frequency at about 0.801 THz and can measure the concentration of alpha-fetoprotein (AFP) in serum. The sensitivity of the sensor is 124 GHz/refractive index unit (RIU), and the quality-factor (Q) is 6.913, respectively. When the surface of the biosensor is covered with healthy serum (AFP≤7ng/mL), the maximum resonance frequency shift is 50 GHz. However, when it is covered with serum from patients with cirrhosis and early HCC (AFP>7ng/mL), the resonance frequency shift is more than 59 GHz. Positive correlation exists between the frequency shift of the biosensor and serum levels of the AFP in the HCC patients. This study provides a method for quick diagnosis and prediction of cirrhosis and HCC.Eddy current pulsed thermography (ECPT) is used to detect rolling contact fatigue (RCF) cracks on the rail. It is observed that some of the cracks disappear in the thermal image with the increase of heating time. Based on the finite element method, with double cracks as the basic unit, three different crack models are established, and the mutual disturbance relationship between the double cracks is discussed based on the eddy current distribution and thermal diffusion process. The simulation and experimental results show that different crack models are affected by thermal diffusion in different heating stages to different degrees, and the time of the crack thermal image disappearance is obtained. According to the above conclusions, the RCF cracks are extracted and classified based on the influence of thermal diffusion. The possibility of rail condition assessment and maintenance based on the disappearance time is explained.We put forward a dual-mode photonic crystal nanobeam cavity for simultaneous sensing of the refractive index (RI) and temperature (T) designed with the assistance of artificial neural networks (ANNs). We choose the structure of quadratically tapered elliptical holes with a slot to improve the sensitivities of the two modes. To reduce the time consumption of the design, the ANNs are trained to predict the band structure and to inverse design the geometric structure. For the forward prediction and the inverse design neural networks, low mean square errors of 5.1×10-4 and 1.4×10-2 are achieved, respectively. Through a specific design of band properties by the well-trained neural networks, a dual-mode nanobeam sensor with high quality factors of 9.34×104 and 1.55×105 and a small footprint of 23.8×0.7µm2 are designed. The RI and T sensitivities of the air mode are 405 nm/RIU and 40 pm/K, respectively, whereas those of the dielectric mode are 531 nm/RIU and 27 pm/K, respectively. The present work shows significance in further research on the design and applications for dual-mode cavities.It is known that the phase response of spatial light modulators (SLMs) measured by double-beam interferometers is sensitive to mechanical and environmental disturbances. This paper proposes a Shack-Hartmann wavefront sensor (SHWS) method to measure the phase response characteristics of the SLM. The results show that the phase modulation depth measured by the proposed method is 1.7581λ, and 1.7993λ by the Twyman-Green interferometer method. The difference in the phase modulation depth between the two methods is only 0.0412λ, and its relative error rate is 2.29%. It proves that the phase modulation accuracy obtained by the SHWS with lenslets of 73*73 used in this paper is equivalent to that of the Twyman-Green interferometer. Compared with the interferometer method, the SHWS method is simple, compact, and robust, has good real-time performance, and is relatively vibration insensitive. In the future, the SHWS method will play a more important role in the detection of the SLM's phase response.Aircraft low observables' features are crucial in the long-wave infrared (LW-IR) band, due to imaging sensors used in IR search and track and in the latest generation of IR-guided missiles. Earthshine irradiance on the aircraft bottom surface is an important source; hence, it is derived using data for atmospheric transmission. Emission due to skin-friction heating (important at high εbot) and earthshine reflection (important at low εbot) are compared by a dimensionless ratio for different bottom surface emissivities (εbot). The infrared cross section of aircraft in direct view from below is obtained in the LW-IR band, which shows that aircraft is seen also due to negative contrast.A tunable and switchable multi-wavelength random distributed feedback fiber laser based on cascaded Sagnac loops is proposed and experimentally demonstrated. The random distribution feedback of the laser is provided by the Rayleigh scattering generated by the single-mode fiber (SMF). The cascaded Sagnac loops act as a filter and a reflector in the half-open cavity laser. The single-, dual-, three-, and four-wavelength channels can be realized by adjusting the angle of the polarization controller at the pump power of 300 mW. In the single-, dual-, and three-wavelength channels, the wavelength spacing can be maintained, and the laser wavelength position can be changed at the same time. The maximum wavelength tuning ranges of single-, dual-, and three-wavelength outputs are about 4.5 nm, 2.6 nm, and 1 nm, respectively. The proposed multi-wavelength random fiber laser has the advantages of simple structure and low threshold, and it has good application prospects in remote sensing and imaging systems.We propose an approach to generate tunable terahertz (THz) radiation from an electron bunch passing over the unique graphene metasurface. We not only control the frequency of the THz radiation but also tune the amplitude and direction of the radiation by varying the chemical potential of the graphene. Several new phenomena are observed. The radiation has the same frequency with the resonant frequency of the graphene metasurface at normal incidence. The radiation frequency meets the linear relationship with the chemical potential. The radiation magnitude is the inverse to the reflection magnitude, and the sum of them is close to being a constant. The strong Smith-Purcell radiation on the graphene metasurface is due to the interaction between the electron bunch and periodic surface plasmon polaritons (SPPs). The stronger the SPP, the higher is the radiation magnitude that is obtained. Cell Cycle inhibitor These results would provide a promising way for developing tunable radiation in the THz band.
Read More: https://www.selleckchem.com/products/AZD1152-HQPA.html
![]() |
Notes is a web-based application for online taking notes. You can take your notes and share with others people. If you like taking long notes, notes.io is designed for you. To date, over 8,000,000,000+ notes created and continuing...
With notes.io;
- * You can take a note from anywhere and any device with internet connection.
- * You can share the notes in social platforms (YouTube, Facebook, Twitter, instagram etc.).
- * You can quickly share your contents without website, blog and e-mail.
- * You don't need to create any Account to share a note. As you wish you can use quick, easy and best shortened notes with sms, websites, e-mail, or messaging services (WhatsApp, iMessage, Telegram, Signal).
- * Notes.io has fabulous infrastructure design for a short link and allows you to share the note as an easy and understandable link.
Fast: Notes.io is built for speed and performance. You can take a notes quickly and browse your archive.
Easy: Notes.io doesn’t require installation. Just write and share note!
Short: Notes.io’s url just 8 character. You’ll get shorten link of your note when you want to share. (Ex: notes.io/q )
Free: Notes.io works for 14 years and has been free since the day it was started.
You immediately create your first note and start sharing with the ones you wish. If you want to contact us, you can use the following communication channels;
Email: [email protected]
Twitter: http://twitter.com/notesio
Instagram: http://instagram.com/notes.io
Facebook: http://facebook.com/notesio
Regards;
Notes.io Team