Researchers from Shanghaitech University, Shanghai Institute of Microsystem and Information Technology, Institute of Geology and Geophysics, Chinese Academy of Sciences have conducted measurements of X-ray fluorescence spectra excited by X-rays and electrons based on microcalorimeters. It was demonstrated that there are obvious differences between the fluorescence spectral lines excited by electrons and photons. This is a good example for elemental analysis based on fluorescence spectra in electron scanning microscopes. It also provides clear guidance for choosing X-ray excitation sources (such as Fe55 or X-ray tubes) or electron excitation sources (such as Sr90) in space exploration.

In the exploration of celestial bodies, such as Mars, the Moon, and asteroids, X-ray fluorescence analysis has emerged as a critical tool for elemental analysis. However, the varying selection rules and excitation sources introduce complexity. Specifically, these discrepancies can cause variations in the intensities of the characteristic spectral lines emitted by identical elements. These variations, compounded by the minimal energy spacing between these spectral lines, pose substantial challenges for conventional silicon drift detectors (SDD), hindering their ability to accurately differentiate these lines and provide detailed insights into the material structure. To overcome this challenge, a cryogenic X-ray spectrometer based on transition-edge sensor (TES) detector arrays is required to achieve precise measurements. This study measured and analyzed the K-edge characteristic lines of copper and the diverse L-edge characteristic lines of tungsten using a comparative analysis of the electron and X-ray excitation processes. For the electron excitation experiments, copper and tungsten targets were employed as X-ray sources, as they emit distinctive X-ray spectra upon electron-beam bombardment. In the photon excitation experiments, a molybdenum target was used to produce a continuous spectrum with the prominent Mo Kα lines to emit pure copper and tungsten samples. TES detectors were used for the comparative spectroscopic analysis. The initial comparison revealed no substantial differences in the Kα and Kβ lines of copper across different excitation sources. Similarly, the Lα lines of tungsten exhibited uniformity under different excitation sources. However, this investigation revealed pronounced differences within the Lβ line series. The study found that XRF spectra preferentially excite outer-shell electrons, in contrast to intrinsic spectra, owing to different photon and electron interaction mechanisms. Photon interactions are selection-rule-dependent and involve a single electron, whereas electron interactions can involve multiple electrons without such limitations. This leads to varied excitation transitions, as evidenced in the observed Lβ line series.

A research team has unveiled a groundbreaking study demonstrating the transformative potential of large language models (LLMs) in plant genomics.

A research team demonstrates the potential of root endophytic fungi (EF) from the halophyte Sesuvium portulacastrum to improve salt tolerance and boost maize growth under saline conditions.

A research team has successfully assembled the first high-quality, chromosome-level genome of published findings reveal how specific genes and hormone regulatory networks drive the plant’s exceptional growth rate and stress tolerance, offering insights into its invasive nature, opening new avenues for sweet potato crop improvement.

Chinese researchers have developed an advanced, high-throughput single-cell sorting platform that enables direct isolation of living cells with targeted metabolic profiles from large mutant libraries.

Traditionally, the duration of LOME was estimated at 1–2 million years. However, the use of advanced high-precision zircon U-Pb dating techniques shows that the extinction occurred on a much shorter timescale, spanning hundreds of thousands of years.

An international research team led by Dr. ZHANG Shukang and postdoctoral researcher Dr. CHOI Seung from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, has conducted a comprehensive study of secondary eggshell units (SEUs) in dinosaur eggshells using techniques including electron backscatter diffraction (EBSD), polarized light microscopy (PLM), and scanning electron microscopy (SEM). For comparison, they examined some eggshells of modern birds, turtles, and crocodiles.

Chinese researchers led by Prof. XIAO Jun at the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences have developed a groundbreaking technology that sheds light on how the three-dimensional (3D) organization of plant genomes influences gene expression—especially in photosynthesis.

Researchers from Tsung-Dao Lee Institute (TDLI) & School of Physics and Astronomy (SPA), Shanghai Jiao Tong University (SJTU) have proposed a lutetium yttrium oxyorthosilicate (LYSO) crystal electromagnetic calorimeter (ECAL)^[1], designed for the DarkSHINE experiment^[2-6]. By precisely measuring the energy loss of electrons after their interaction with a target, the ECAL is designed to search for invisibly decay products of dark photons. Featuring excellent energy resolution and strong radiation tolerance, this calorimeter significantly enhances the sensitivity of dark photon detection.