Linear relationship between reactivity and the reciprocal of uranium concentration in thermal-spectrum molten salt reactors
Peer-Reviewed Publication
Updates every hour. Last Updated: 6-May-2026 01:15 ET (6-May-2026 05:15 GMT/UTC)
Through theoretical derivation, researchers have concluded that a simple linear relationship exists between the reactivity of molten salt reactors and the reciprocal of uranium concentration in the fuel salt. This relationship has been validated through numerical simulations, demonstrating its general applicability, which is expected to have a far-reaching impact on the theoretical development of reactor physics.
Life begins with a single fertilized cell that gradually transforms into a multicellular organism. This process requires precise coordination; otherwise, the embryo could develop serious complications. Scientists at ISTA have now demonstrated that the zebrafish eggs, in particular their curvature, might be the instruction manual that keeps cell division on schedule and activates the appropriate genes in a patterned manner to direct correct cell fate acquisition. These insights, published in Nature Physics, could help improve the accuracy of embryo assessments in IVF.
Researchers at Kumamoto University, in collaboration with colleagues in South Korea and Taiwan, have discovered that a unique cobalt-based molecule with metal–metal bonds can function as a spin quantum bit (spin qubit)—a fundamental unit for future quantum computers. The findings provide a new design strategy for molecular materials used in quantum information technologies.
Researchers able to track for the first time how a particularly active region of the sun develops over three solar rotations using two space probes.
Such observations help to better predict space weather.
The super -active region triggered the strongest solar storm observed in the last twenty years in May 2024.
Solar storms have the potential to cause significant disruption to modern technologies, including navigation, communication, and power systems.
Exciton polaritons are hybrid light-matter quantum states arising from strong coupling, offering a unique platform for exploring macroscopic quantum phenomena. However, how the coherence of external driving laser field is transferred to polaritons has remained an open question. Recently, the team of Prof. Jian Wu at East China Normal University achieved a critical breakthrough in this area. By combining femtosecond angle-resolved spectroscopic imaging with interferometry, they directly observed the transfer of laser coherence to resonantly excited exciton polaritons within hundreds of femtoseconds at room temperature. They further uncovered the physical mechanism by which non-resonant polaritons lose coherence under high pump power due to a decoherence process mediated by the exciton reservoir. These findings have been published under the title "Femtosecond coherence dynamics of exciton polaritons" in National Science Review. Haoyuan Jia, a PhD candidate at East China Normal University, is the first author, with co-corresponding authors including Prof. Jian Wu and Prof. Hui Li (East China Normal University), Dr. Junhui Cao (Moscow Institute of Physics and Technology), and Prof. Tim Byrnes (NYU Shanghai).
An international team of researchers have developed a novel hybrid detection system HALIMA at the Institute of Modern Physics to facilitate the measurement of the sub-nanosecond lifetimes of neutron-rich nuclei produced via fission. This system is composed of eight BGO-shielded HPGe detectors and 20 fast LaBr3(Ce) detectors, each shielded with CsI(Tl), offering high-resolution γ-ray energy and timing capabilities. To enhance event selectivity, two specialized ancillary detector arrays were incorporated: a solar cell detector array for detecting fission fragments (FFs) and a fast plastic scintillator array for β-particle detection. These additions enable advanced coincidence techniques, such as FFs/β-GeLaBr3(Ce)-LaBr3(Ce), significantly improving the spectral quality and peak-to-background, thereby allowing precise lifetime measurements. A commissioning experiment using a 252Cf source was conducted to validate the performance of the HALIMA setup. By applying combined gating to FFs and fast plastic scintillators, the lifetimes of three excited nuclear states in 134Te, 138Ba, and 132Te were measured, covering a range from a few picoseconds to several hundred nanoseconds.The results were in good agreement with the literature values, demonstrating the capability and precision of the HALIMA setup. Furthermore, several excited states with previously unmeasured lifetimes produced by 252Cf fission were identified for the first time, thereby opening new avenues for nuclear structure studies of neutron-rich nuclei.