An x-ray framing camera based on pulse-dilation technology is reported. This first dilates the electron signal generated from a pulsed photo-cathode (PC), and then detects dilated pulse by using gated microchannel plate (MCP). While PC only applied with direct current (DC) voltage, camera's temporal resolution without about 81 ps. It MCP's resolution. an excitation PC, pulse's width dilated, improved to 14 Furthermore, uniformity measured simulated. The results show 3.5 × drop in along...

Abstract Fabry Perot interferometer (FPI) is an essential ground‐based passive optical observation device to detect middle and upper atmospheric information. Three FPIs are located at Kunming (103.8°E, 25.6°N), Xinglong (117.4°E, 40.2°N), Mohe (122.3°E, 53.5°N), China. The diurnal annual variation of night wind 87, 97, 250 km investigated from 2019 2021, compared Horizontal Wind Model 14 (HWM14) check the prediction accuracy for local field. Our results as follows: (a) At 87 km, zonal winds...

Using version 1.0 of TIMED/SABER nighttime O(3P) density data in the mesosphere and lower thermosphere (MLT) retrieved from 2.0 1.6 μm radiances, we conducted a study on semiannual oscillation (SAO), annual (AO) quasi-biennial (QBO) atomic oxygen volume mixing ratio at 96 km, 40° S to N, for 2002–2019. We first analyzed altitude profiles kinetic temperature, chose daily average km. For analysis SAO AO, fitted two sinusoidal functions with periods 6 12 months mean obtain amplitude. The...

Non-line-of-sight (NLOS) tracking has drawn increasing attention in recent years, due to its ability detect object motion out of sight. Most previous works on NLOS rely active illumination, e.g., laser, and suffer from high cost elaborate experimental conditions. Besides, these techniques are still far practical application oversimplified settings. In contrast, we propose a purely passive method track person walking an invisible room by only observing relay wall, which is more line with real...

An x-ray detector using a pulse-dilation technology to achieve high temporal resolution is reported. The electron pulse generated from the photo-cathode (PC) first dilated by device and then imaged onto microchannel plate (MCP) magnetic lens imaging system. Finally, detected gated MCP. A of 14 ps achieved. In addition, synchronous gating studied in dilation without 1:1 image ratio. results show that while time flight (TOF) electrons identical, MCP can be timed relative PC excitation gate...

Abstract Polymeric materials with antibacterial properties hold great promise for combating multidrug‐resistant bacteria, which pose a significant threat to public health. However, the synthesis of most polymers typically involves complicated and time‐consuming procedures. In this study, we demonstrate simple efficient strategy synthesizing functional poly(vinylpyridinium salt)s via pyridinium‐yne click polymerization. This polymerization could proceed high atom economy under mild conditions...

Abstract Polymeric materials with antibacterial properties hold great promise for combating multidrug‐resistant bacteria, which pose a significant threat to public health. However, the synthesis of most polymers typically involves complicated and time‐consuming procedures. In this study, we demonstrate simple efficient strategy synthesizing functional poly(vinylpyridinium salt)s via pyridinium‐yne click polymerization. This polymerization could proceed high atom economy under mild conditions...

Numerical relativity simulations predict that coalescence of supermassive black hole (SMBH) binaries leads not only to a spin flip but also recoiling the merger remnant SMBHs. In literature, X-shaped radio sources are popularly suggested be candidates for SMBH mergers with jet-ejecting Here we investigate spectral and spatial observational signatures SMBHs in undergoing flip. Our results show most spin-flip have mass ratio q ≳ 0.3 minimum possible value qmin ≃ 0.05. For major mergers, can...

In this paper, we proposed an ultrafast 3-D imaging system based on phase-shifting method and a hybrid dispersion scanning technique. The is capable of acquiring the shape object at scan rate. A theoretical model built to describe operation principle analyze performance system. demonstration, designed with practical devices components. has rate 25 MHz frame 100 kHz. field view 50 μm × μm, number pixels one 260 pixel 1000 pixel. reconstructed image peak signal-to-noise ratio (PSNR) 30.11 dB....

We present for the first time a surface plasmon-enhanced dark-field microsphere-assisted microscopy in imaging both low-contrast dielectric objects and metallic ones. demonstrate, using an Al patch array as substrate, resolution contrast are improved compared to that of metal plate substrate glass slide (DFM). 365-nm-diameter hexagonally arranged SiO nanodots assembled on three substrates can be resolved, with varied from 0.23 0.96, 300-nm-diameter close-packed polystyrene nanoparticles only...

A pulse dilation photomultiplier tube (PD-PMT) has been developed. The photoelectrons energy is modulated by a time-dependent electric field between photocathode and ground mesh. Then, the photoelectron dilated as it transits in relatively long drift region from mesh to microchannel plate (MCP). electron gained MCP then detected output collector. Because temporal width magnified, resolution of better than that collector alone. result shows detector improved be 25 ps using pulse-dilation...

A two-dimensional ultrafast X-ray imager (UXI) composed of a time-dilation device, an electron-beam imaging unit, gated microchannel plate (MCP) framing tube, and pulser was developed. The device extends the time spread electron signal generated by pulsed photocathode (PC), unit images pulse from PC to MCP. Finally, MCP tube samples dilated pulse. resolution image size UXI were measured with terawatt laser targeting device. When driving 2 V/ps slope is applied PC, 21 ps, 12 mm × 3.9 mm....

The vertically integrated emission rate, centroid altitude, peak and height of the OH airglow were calculated from TIMED/SABER observations to study seasonal interannual variations in intensity location emission. rate is inversely proportional emission, with semi-annual oscillation (SAO) dominating at low latitudes annual (AO) higher latitudes. modulated by quasi-biennial (QBO) equator QBO signal weak other We represent vertical transport atomic oxygen using concentrations obtained a global...

Abstract The Gas Microchannel plate Pixel Detector (GMPD) is purposefully designed and manufactured for astrophysical X-ray polarization detection, slated use in various space missions such as the Cosmic Polarization (CXPD) CubeSat, Low Energy Polarimeter (LPD/POLAR-2), Chasing All Transients Constellation Hunters (CATCH). Past research has explored spectral performance of GMPD. This study, first time, experimentally investigates its imaging characteristics to validate capabilities....

Abstract The geopotential height observations from the Aura Microwave Limb Sounder show that quasi‐6‐day wave (Q6DW) events with westward zonal wavenumber 1 (W1) in Northern Hemisphere (NH) mesosphere and lower thermosphere (MLT) during September 2013 2014 had a prolonged lifetime of ∼45–50 days reached their maximum amplitudes after equinox, while climatological Q6DW‐W1 is completely dissipated background atmosphere before equinoxes. Eliassen‐Palm flux diagnostic results indicate obtained...

Large-scale generative models have achieved remarkable advancements in various visual tasks, yet their application to shadow removal images remains challenging. These often generate diverse, realistic details without adequate focus on fidelity, failing meet the crucial requirements of removal, which necessitates precise preservation image content. In contrast prior approaches that aimed regenerate shadow-free from scratch, this paper utilizes diffusion and refine residuals. This strategy...