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The study of facile‐synthesis and low‐cost X‐ray scintillators with high light yield, low detection limit and high X‐ray imaging resolution plays a vital role in medical and industrial imaging fields. However, the optimal balance between X‐ray absorption, decay lifetime and excitonic utilization efficiency of scintillators to achieve high‐resolution imaging is extremely difficult due to the inherent contradiction. Here two thermally activated delayed fluorescence (TADF)‐actived coinage‐metal clusters M6S6L6 (M=Ag or Cu) were synthesized by simple solvothermal reaction, where the cooperation of heavy atom‐rich character and TADF mechanism supports strong X‐ray absorption and rapid luminescent collection of excitons. Excitingly, Ag6S6L6 (SC‐Ag) displays a high photoluminescence quantum yield of 91.6 % and scintillating light yield of 17420 photons MeV−1, as well as a low detection limit of 208.65 nGy s−1 that is 26 times lower than the medical standard (5.5 μGy s−1). More importantly, a high X‐ray imaging resolution of 16 lp/mm based on SC‐Ag screen is demonstrated. Besides, rigid core skeleton reinforced by metallophilicity endows clusters M6S6L6 strong resistance to humidity and radiation. This work provides a new view for the design of efficient scintillators and opens the research door for silver clusters in scintillation application. [ABSTRACT FROM AUTHOR]

In this article, the design, simulation, fabrication and measurement of an ultrathin and wide band radar metamaterial absorber (MMA) are introduced. The unit of the MMA consists of two different sizes of L-shaped structure and a perfect electric conductor separated by 2 mm dielectric layer (only 0.074 λ to 0.156 λ at lowest and highest frequencies, respectively). The simulation results show that the proposed MMA has more than 90% good absorption (below −10 dB) in the frequency range of 11.07–23.36 GHz. By adjusting the scale of the unit, the absorption characteristics of the proposed absorber can be adjusted and moved to the frequency range which we are interested in. The absorption mechanism of the proposed absorber is also analyzed by field and surface current distributions. The proposed absorber has been fabricated and experimentally tested for absorbing properties at different angles of incidence and different polarizations. The experimental results show the absorption rates are consistent with the simulation results. The proposed absorber has potential applications in stealth technology. [ABSTRACT FROM AUTHOR]

Taking Yilan Basin which is a typical Cenozoic fault basin for example, the occurrence and forming conditions were studied on shale, oil shale and coal based on field section profiles and comprehensive analysis indoors. Furthermore, the genesis and metallogenic regularities of coal and oil shale were showed by studying on paleoclimte, paleoenvironment and paleotectonic conditions. Coal-bearing beds of coal co-occurring with oil shale easily formed during episodic movement of tectonic subsidence at the beginning of the basin evolution. Coal deposited in shallow lacustrine basin of the fan front, and oil shale directly deposited on the coal interval, while oil shale stable sedimentary time during lake-basin expansion. Coal formed in lake marsh, while oil shale deposited in lake marsh and lacustrine. Coal and oil shale distributions were controlled by the basin-controlling fault of Yilan Basin, and became thicker near the F1 fault. That shows gradually onlapping from the lake level with the increasing depositing range of the lake basin. Coal mainly formed at warm and damp conditions, while the climate of oil shale formation generally tended to mild and a temperature decrease based on spore and pollen analysis. It was the subtropical climate, warm and damp, and the wind was weak at the lake level when the lake of Dalianhe Formation was developing. And that climate favored the formation of deep to semi-deep lake environment which was reducing and stable and easily made for oil shale. The achievements above will shape some theoretical foundations for exploring energy basins which are rich in resources of oil and gas, shale gas and coal-bed gas. [ABSTRACT FROM AUTHOR]

The study of facile-synthesis and low-cost X-ray scintillators with high light yield, low detection limit and high X-ray imaging resolution plays a vital role in medical and industrial imaging fields. However, the optimal balance between X-ray absorption, decay lifetime and excitonic utilization efficiency of scintillators to achieve high-resolution imaging is extremely difficult due to the inherent contradiction. Here two thermally activated delayed fluorescence (TADF)-actived coinage-metal clusters M 6 S 6 L 6 (M=Ag or Cu) were synthesized by simple solvothermal reaction, where the cooperation of heavy atom-rich character and TADF mechanism supports strong X-ray absorption and rapid luminescent collection of excitons. Excitingly, Ag 6 S 6 L 6 (SC-Ag) displays a high photoluminescence quantum yield of 91.6 % and scintillating light yield of 17420 photons MeV -1 , as well as a low detection limit of 208.65 nGy s -1 that is 26 times lower than the medical standard (5.5 μGy s -1 ). More importantly, a high X-ray imaging resolution of 16 lp/mm based on SC-Ag screen is demonstrated. Besides, rigid core skeleton reinforced by metallophilicity endows clusters M 6 S 6 L 6 strong resistance to humidity and radiation. This work provides a new view for the design of efficient scintillators and opens the research door for silver clusters in scintillation application., (© 2023 Wiley-VCH GmbH.)

Two examples of efficient cathode-ray scintillation coordination polymers with good stability at high voltage were prepared by conjugating luminescent groups with d 10 metal ions. The synergistic effect of inorganic metal and organic ligand suppresses the self-quenching of the conjugated luminescent groups and enhances the scintillation performance. This work provides new ideas for the design of new field-emission displays and cathode-ray scintillation materials.