All-inorganic perovskite CsPbBr3 quantum dots (QDs) with an emission peak of around 520 nm were synthesized by a hot-injection method, and systematically studied as green phosphor for light-emitting diodes (LEDs). Highly pure light 534 full-width at half-maximum (FWHM) about 20 was achieved using QDs GaN LEDs. Commission Internationale Ed I'Eclairage coordinate the fabricated LEDs (0.203, 0.757). Compared to LEDs, current-voltage characteristic LED did not show any degradation. Moreover,...

The Raman spectra of nanometer-sized particles SnO2 (3–90 nm) at room temperature are reported. In the SnO2, which quite different from that single-crystal there appear two new characteristic peaks, and their intensities decrease gradually with increase crystal size. It is concluded peaks can be explained by surface phonon modes nanometer consequently a relation between structures layers bulk. believed it possible to determine exact positions atoms in some crystals laser spectra.

Two-dimensional digital microfluidic platforms, on which droplets are actuated by electrowetting dielectrics, have merits such as dynamic reconfigurability and ease for automation. However, concerns platforms based low-cost printed circuit boards, the scalability of electrode array reliability device operation, should be addressed before high throughput fully automatic applications can realized. In this work we report progress in addressing those issues using active-matrix circuitry to...

Utilizing the periodicity of rotating machinery, dynamic clearance measurement can be achieved with a single swept light source without any additional auxiliary devices, which has advantages simplicity and reliability. However, there is shortcoming that previous algorithm not fast enough to achieve real-time when machinery rotates at high speed. Aiming this shortcoming, utilizing correlation between mimic signal signal, combined information for multiple periods, algorithms corrected model...

The fabrication of high quality and low cost microlenses on a glass substrate using simple, rapid, precise direct microplotting technique is shown in this paper. method based the use microplotter system, which significantly different from existing inkjet, roll-to-roll printing, reactive ion etching technology could work with higher viscosity materials. By optimizing parameters voltage, dispense time, concentration polymer solution, diameter 20 μm be obtained. geometrical optical...

Stress-induced birefringence can lead to distortion in the reflection spectra of fiber Bragg grating (FBG) sensors, thereby resulting loss accuracy and stability strain measurements. The bonding layer is a direct factor producing stress within FBGs. To assess impacts quantitatively, theoretical model that links spectrum was established. At same time, finite element method, based on model, used study relationships between characteristics detail. analytical results indicate high elastic...

The performance and reliability of the high-power light-emitting diodes (HP LEDs) are closely related to quality die attach adhesive (DAA) layer, because voids or delaminations in layer may cause higher junction temperature, even result break chip. In this paper, a dynamic compact thermal model is constructed for an independent HP LED without being attached on cold plate. time-constant spectrum method based applied characterize transient behavior DAA other layers along heat flow path....

Frequency-sweep interferometry (FSI) technology enables high-speed axial clearance measurements but is subject to errors caused by the Doppler effect. Adding auxiliary paths eliminate effect may cause slower measurement speed and low accuracy. In this article, characteristics of variations are analyzed. Subsequently, a correlation-changed empirical mode decomposition (Cor-CEMD) algorithm developed. The optimal construction value coarsely located correlation algorithm, minimizing amount...

X-ray powder diffraction and high-resolution transmission electron microscopy (HRTEM) have found coexistence of three structures GaN: wurtzite, zinc blende, rocksalt in the samples prepared through benzene thermal process at 280–300 °C under pressure about 5 MPa. Previously, GaN with structure only appeared high more than 37 GPa. HRTEM showed that there was a transitional region between two cubic phases blende rocksalt. photoelectron spectra analysis sample gave average composition Ga0.95N.

A fast real-time demodulation method based on the coarsely sampled spectrum is proposed for transient signals of fiber optic extrinsic Fabry-Perot interferometers (EFPI) sensors. The feasibility phase using a coarse theoretically analyzed. Based spectrum, Fourier transform (FFT) algorithm used to roughly estimate cavity length. According rough estimation, maximum likelihood estimation (MLE) applied calculate length accurately. dense wavelength division multiplexer (DWDM) split broadband into...

The common-source noise-canceling (CSNC) and the gyrator are known for alleviating trade-off between NF S11 in wideband LNAs. Moreover, departure of input-matching stage signal-amplifying CSNC facilitates design gyrator. Cascode configuration is exploited to boost feedback gain, enhancing gyrator-C effect broadening bandwidth. Therefore, large transistors can be used noise reduction while maintaining a wide operating Post-layout simulation results 40 nm CMOS technology show that circuit...

Abstract Fiber optic sensors have been gradually used in aerospace, petrochemical, electronic power, civil engineering, and biomedical fields because of their many advantages such as the anti-electromagnetic interference, corrosion resistance, light weight, small size, high accuracy, easy reuse. In recent years, sensing demodulation technologies based on microwave photonics attracted widespread attention. Optical fiber combined with has higher sensitivity flexibility, which is important for...

In situ temperature near the chips in a multiple-chip power semiconductor module is important information for thermal design validation, condition monitoring, and overheat protection. Due to compact packaging structure clamping force, online detection of challenging press-pack module. This study attempts achieve measurement by integrating optical fiber Bragg grating (FBG) sensors into device. Different integration schemes are examined using experiments theoretical analysis show effects on...

The wavelength of microwave is longer than that lightwave, causing the interferometric optical path difference induced by measurand changes to be relatively smaller microwave, which results in lower sensitivity sapphire fiber Fabry-Perot interferometer (FPI) sensor band. To improve sensitivity, a parallel FPI sensing system constructed, section connected single-mode transmission used as FPI, and (SMF) with slightly different from utilized reference FPI. By connecting two FPIs parallel,...

This paper proposes an adaptive Particle Swarm Optimization(APSO) global search algorithm and Spiking Neural Network(SNN) surrogate model-based optimization design method for analog integrated circuits performance enhancement. The initial parameters are calculated by numerical computation. space is extended explored using APSO in the main loop, with constraint testing ensuring transistor works right conditions. A Network (SNN) model aids predicting circuit during local searches, which...

Most of the lighting designs are based on far-field characteristics light sources. It is important to know whether measurement distance far enough simulate source as a point source. In this paper, we deduce conditions for surface sources with continuous luminous area. The relative several typical flat and curved sources, such round, rectangular, annular, hemispherical, semi-cylindrical calculated. Results show that classical five times rule not applicable arc-shaped semi-cylindrical, narrow...

The optical path length (OPL) of the Fabry-Perot cavity may change during spectrum acquisition; it introduces demodulationerror or even causes demodulation failure based on traditional algorithms. To address this problem, relationship between dynamic OPL and instantaneous frequency is investigated. Demodulation analysis proposed. By combining spectrogram (SP) Wigner-Ville Distribution (WVD), an effective time-frequency (TF) method investigated to calculate at each sampling point in a period...