The cycling stability of LiNi0.8Co0.1Mn0.1O2 under high voltages is hindered by the occurrence of hybrid anion- and cation-redox processes, leading to oxygen escape and uncontrolled phase collapse. In this study, an interfacial engineering strategy involving a straightforward mechanical ball milling and low-temperature calcination, employing a Se-doped and FeSe2&Fe2O3-modified approach is proposed to design a stable Ni-rich cathode. Se2- are selectively adsorbed within oxygen vacancies to form O─TM─Se bond, effectively stabilizing lattice oxygen, and preventing structural distortion. Simultaneously, the Se-NCM811//FeSe2//Fe2O3 self-assembled electric field is activated, improving interfacial charge transfer and coupling. Furthermore, FeSe2 accelerates Li+ diffusion and reacts with oxygen to form Fe2O3 and SeO2. The Fe2O3 coating mitigates hydrofluoric acid erosion and acts as an electrostatic shield layer, limiting the outward migration of oxygen anions. Impressively, the modified materials exhibit significantly improved electrochemical performance, with a capacity retention of 79.7% after 500 cycles at 1C under 4.5 V. Furthermore, it provides an extraordinary capacity retention of 94.6% in 3-4.25 V after 550 cycles in pouch-type full battery. This dual-modification approach demonstrates its feasibility and opens new perspective for the development of stable lithium-ion batteries operating at high voltages.

Electrosynthesis of urea from CO 2 and NO 3 − is a sustainable alternative to energy-intensive industrial processes. The main challenge hindering the progress of this technology lies in the development of advanced electrocatalysts that efficiently utilize abundant, low-cost CO 2 and nitrogen sources to yield urea with both high Faradaic efficiency (FE) and current density. In this work, we designed and prepared a new two-dimensional metal–organic framework (MOF), namely PcNi−Fe−O , constructed by nickel-phthalocyanine (NiPc) ligands and square-planar FeO 4 nodes, as the electrocatalyst for urea electrosynthesis. PcNi−Fe−O exhibits remarkable performance to yield urea at a high current density of 10.1 mA cm −2 with a high FE(urea) of 54.1 % in a neutral aqueous solution, surpassing those of most reported electrocatalysts. No obvious performance degradation was observed over 20 hours of continuous operation at the current density of 10.1 mA cm −2 . By expanding the electrode area to 25 cm 2 and operating for 8 hours, we obtained 0.164 g of high-purity urea, underscoring its potential for industrial applications. Mechanism study unveiled the enhanced performance might be ascribed to the synergistic interaction between NiPc and FeO 4 sites. Specifically, NH 3 produced at the FeO 4 site can efficiently migrate and couple with the *NHCOOH intermediate adsorbed on the urea-producing site (NiPc). This synergistic effect results in a lower energy barrier for C−N bond formation than those of the reported catalysts with single active sites.

Simultaneously enhancing selectivity and stability on supported propane dehydrogenation (PDH) catalysts remains a formidable challenge. Here, we report a combined static and dynamic strategy to address these issues synergistically. Firstly, we demonstrate a feasible sol‐gel method for preparing atomically‐dispersed Bi‐decorated metal nanoparticle catalysts (MBi/Al2O3, M= Fe, Co, Ni, and Zn). In PDH testing, the total selectivity of by‐products (CH4 and C2H6) significantly decreases to 4% for CoBi catalysts due to the static Bi‐doping, compared with 16% for Co‐supported catalysts. Secondly, to enhance catalytic stability, we introduce a dynamic trace CO2 co‐feeding route. 10CoBi/Al2O3 catalysts exhibit superior durability against coke formation for 330 hours in PDH under a 40% C3H8 atmosphere followed by pure C3H8 conditions at 600 °C while maintaining propylene selectivity at 96%. Notably, introducing trace CO2 leads to a remarkable 6‐fold decrease in the deactivation rate constant (kd). Multiple characterizations and density functional theory calculations reveal that charge transfer from atomically‐distributed Bi to Co nanoparticles benefits lowering the energy of C3H6 adsorption thereby suppressing by‐products. Furthermore, the dynamic co‐feeding of trace CO2 facilitates coke removal, suppressing catalyst deactivation. The static Bi‐doping and dynamic trace CO2 co‐feeding strategy contributes simultaneously to increased selectivity and stability on supported PDH catalysts.

It is crucial to achieve continuous production of highly concentrated and pure C2 chemicals through the electrochemical CO2 reduction reaction (eCO2RR) for artificial carbon cycling, yet it has remained unattainable until now. Despite one-pot tandem catalysis (dividing the eCO2RR to C2 into two catalytical reactions of CO2 to CO and CO to C2) offering the potential for significantly enhancing reaction efficiency, its mechanism remains unclear and its performance is unsatisfactory. Herein, we selected different CO2-to-CO catalysts and CO-to-acetate catalysts to construct several tandem catalytic systems for the eCO2RR to acetic acid. Among them, a tandem catalytic system comprising a covalent organic framework (PcNi-DMTP) and a metal-organic framework (MAF-2) as CO2-to-CO and CO-to-acetate catalysts, respectively, exhibited a faradaic efficiency of 51.2% with a current density of 410 mA cm-2 and an ultrahigh acetate yield rate of 2.72 mmol m-2 s-1 under neutral conditions. After electrolysis for 200 h, 1 cm-2 working electrode can continuously produce 20 mM acetic acid aqueous solution with a relative purity of 95+%. Comprehensive studies revealed that the performance of tandem catalysts is influenced not only by the CO supply-demand relationship and electron competition between the two catalytic processes in the one-pot tandem system but also by the performance of the CO-to-C2 catalyst under diluted CO conditions.

Accurate and efficient extraction of tree parameters from plantations lay foundation for estimating individual wood volume and stand stocking. In this study, we proposed a method of extracting high-precision tree parameters based on airborne LiDAR data. The main process included data pre-processing, ground filtering, individual tree segmentation, and parameter extraction. We collected high-density airborne point cloud data from the large-diameter timber of Fokienia hodginsii plantation in Guanzhuang State Forestry Farm, Shaxian County, Fujian Province, and pre-processed the point cloud data by denoising, resampling and normalization. The vegetation point clouds and ground point clouds were separated by the Cloth Simulation Filter (CSF). The former data were interpolated using the Delaunay triangulation mesh method to generate a digital surface model (DSM), while the latter data were interpolated using the Inverse Distance Weighted to generate a digital elevation model (DEM). After that, we obtained the canopy height model (CHM) through the difference operation between the two, and analyzed the CHM with varying resolutions by the watershed algorithm on the accuracy of individual tree segmentation and parameter extraction. We used the point cloud distance clustering algorithm to segment the normalized vegetation point cloud into individual trees, and analyzed the effects of different distance thresholds on the accuracy of indivi-dual tree segmentation and parameter extraction. The results showed that the watershed algorithm for extracting tree height of 0.3 m resolution CHM had highest comprehensive evaluation index of 91.1% for individual tree segmentation and superior accuracy with R2 of 0.967 and RMSE of 0.890 m. When the spacing threshold of the point cloud segmentation algorithm was the average crown diameter, the highest comprehensive evaluation index of 91.3% for individual tree segmentation, the extraction accuracy of the crown diameter was superior, with R2 of 0.937 and RMSE of 0.418 m. Tree height, crown diameter, tree density, and spatial distribution of trees were estimated. There were 5994 F. hodginsii, with an average tree height of 16.63 m and crown diameter of 3.98 m. Trees with height of 15-20 m were the most numerous (a total of 2661), followed by those between 10-15 m. This method of forest parameter extraction was useful for monitoring and managing plantations.

Given the ecological, cultural and psychological functions of urban vegetation, a growing number of studies have focused on daily accessible greenery visibility. Mobile laser scanning (MLS) can rapidly obtain dense point clouds that can be used to extract vegetation. To address this issue, we propose a novel method for calculating the green view index (GVI) based on MLS three-dimensional (3D) point clouds. In our study, the GVI was specified as the ratio of greenery viewing angles to the total number of viewing angles in view. The GVI calculation procedure was as follows. First, the vegetation points were extracted using the density-based spatial clustering of applications with noise (DBSCAN) algorithm and the PointNet++ deep learning algorithm. Second, based on the GVI specification, a virtual camera was constructed in a 3D point scenario to estimate greenery viewing angles in view and generate depth images, and then, the GVI value was calculated. This method is flexible and can be used to calculate the GVI at any site with any direction where 3D point scene data are available, and thus, it is suitable for evaluating various types of urban greenery. We conducted a case human-centered assessment of road greenery in a partial area of Jinshan District in Fuzhou, China, based on MLS point clouds, evaluating visible greenery and analyzing the relations among the GVI, greening pattern, and road green belt mode. The results showed that the overall visible greenery in the study area was good and that the GVI value of most road sections was more than 15 %. The method has potential for urban green space planning and management.

Precise regulation of the coordination environment of a metal active center is very important but remains a challenge. Here, single-atom Ni catalysts with a combined N- and C-coordination structure ( Ni-NC3) and N-coordination structure ( Ni-N-4) were prepared by modulating the side groups of organic ligands in the corresponding precursor metal-azolate frameworks. Compared with the Ni-N-4 site, the d-band center of 3d orbitals of the Ni atom in Ni-NC3 was more significantly shifted to the Fermi energy level; thus, the Ni-NC3 catalytic site was superior to activating CO2 molecule into the *COOH intermediate. As a result, Ni-NC3 exhibited an exceptionally high performance for CO2-to-CO conversion with a Faradaic efficiency of 98.4%, an energy efficiency of >50%, as well as an industrial current density of similar to 300 mA cm(-2) in neutral electrolyte. Such high performance could be retained for at least 70 h. This work reveals the importance of modulating the coordination environment in the electrochemical CO2 reduction reaction and provides a possible way to rational design of electrocatalysts for highly efficient conversion of CO2 to target products.

The nuclear resonant scattering (NRS) experiment requires photon-counting detectors with high time resolution, short dead time, large dynamic range, low noise, and large detection area. An 8-channel avalanche photodiode (APD) array detector system with high integrity, flexibility, and reliability has been developed to adapt to the demands of NRS experiments. The detector system mainly consists of four key parts: (i) an array-APD sensor, (ii) 8-channel integrated fast preamplifiers, (iii) the time-to-digital converter readout electronics, and (iv) a data acquisition system and EPICS support software. Remarkably, the system exhibits a time resolution of better than 500 ps and has a sufficiently low noise level, allowing for the lowest detection energy threshold of 4 keV. The performance of the new array-APD system as well as its real application in nuclear forward scattering (NFS) and nuclear resonant inelastic x-ray scattering (NRIXS) experiments was tested in two synchrotron facilities. With the new system, the NFS signal very close to the prompt electronic scattering signal can be extracted. Thanks to the customized EPICS-area Detector-based control software, NRIXS spectra can be readily measured with time and energy information of the NRIXS signal stored in the raw data, which is promising for developing NRIXS data analysis in the time domain. The array-APD detector can be deployed for nuclear resonant scattering experiments at various synchrotron radiation facilities.

Gram scale preparation of carbon-supported single-atom catalysts was achieved via a top-down approach starting from metallic and metalloid constituent-enriched gasification residual carbon, exhibiting superior electrocatalytic performance for CO2-to-CO conversion in both H-type and membrane electrode assembly electrolyzers.

The [NiFe] heterobinuclear hydrogenase active site in nature is responsible for a typical 2e(-) and 2H(+) transformation with extraordinarily efficient H-2 evolution. However, the difficulty in isolating the [NiFe] catalytic center and the sensitivity to air pose great challenges to unravelling the detailed 2e (-)/2H(+) process. Herein, we design and synthesize a [(NiMnBr)-Mn-II-Br-I] ((dppe)Ni-II(m-pdt)(m-Br)MnI(CO)(3)) heterobinuclear mimic to track the reaction processes. Our results reveal that [(NiMnBr)-Mn-II-Br-I] is reduced to form [(NiMnH)-Mn-II-H-I] ((dppe) Ni-II(m-pdt)(m-H)Mn-I(CO)(3)) in the presence of a proton (H+). IR-SEC, NMR, and X-ray crystal-structure analyses identify that the key [(NiMnH)-Mn-II-H-I] intermediate interacts with a strong acid for H2 evolution via Mn ([(NiMnII)-Mn-II/IH]), whereas in the presence of a weak acid, further 1e(-) reduction at the Ni site affords [(NiMnH)-Mn-I-H-I](-)-R species to react with H+. The full 2e( -)/2H(+) H-2 evolution picture of the heterobinuclear mimic relying on different metal centers presents a unique mechanistic understanding of hydrogenase mimics.

The electrolyte cations-dependent kinetics have been widely observed in many fields of electrocatalysis, however, the exact mechanism of the influence on catalytic performance is still a controversial topic of considerable discussion. Herein, combined with operando X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM), we verify that the electrolyte cations could intercalate into the layer of pristine CoOOH catalyst during the oxygen evolution reaction (OER) process, while the bigger cations lead to enlarged interlayer spacing and increased OER activity, following the order Cs+ >K+ >Na+ >Li+ . X-ray absorption spectroscopy (XAS), in situ Raman, in situ Ultraviolet-visible (UV/Vis) spectroscopy, in situ XAS spectroscopy, cyclic voltammetry (CV), and theoretical calculations reveal that the intercalation of electrolyte cations efficiently modify the oxidation states of Co by enlarging the Co-O bonds, which in turn enhance the d-band center of Co, optimize the adsorption strength of oxygen intermediates, facilitate the formation of OER active Co(IV) species, and reduce the energy barrier of the rate-determing step (RDS), thereby enhancing the OER activity. This work not only provides an informative picture to understand the complicated dependence of OER kinetics on electrolyte cations, but also sheds light on understanding the mechanism of other electrolyte cation-targeted electrocatalysis.

This article presents the development of small sized piezoelectric micromachined ultrasound transducer (PMUT) with cost effective fabrication process. Improved ultrasound imaging quality requires small sized, high frequency and high performance PMUT cell and further high density arrays. Fabrication with currently well developed and cost effective sacrificial process benefits their mass production and application. To determine small sized AlN PMUT cell, commonly reported elastic layer materials including Si, Si3N4, SiO2 are compared by mathematic derivation under the same stack thickness and device frequency. SiO2 has the smallest Young modulus and it serving as elastic layer can yield the expected one. Arranging SiO2 layer at the top of the device is compatible with phosphor silicate glass (PSG) sacrificial manufacturing process for cost effective fabrication. This fabrication strategy further downsizes cell size since extra device protection layer is omissible. We make 12MHz PMUT linear arrays with cell diameter, thickness and element pitch to be $40~\mu \text{m}$ , $1.9~\mu \text{m}$ and $120~\mu \text{m}$ . Their electrical and ultrasound results are quite uniform at both device and wafer levels. One PMUT line with 20 parallelly connected units can produce pulse-echo signal with over 25dB SNR at 10mm distance. Lateral and axial ultrasound imaging resolutions of ~1 mm and ~0.3 mm are obtained in practical verification. These indicate the good ultrasound performance of our developed PMUT array. Plus the advantages of small size and cost effective fabrication, using SiO2 elastic layer and arranging it at the top of the device is a competitive strategy to develop phased array PMUTs. [2022-0184]

It is challenging and important to achieve high performance for an electrochemical CO2 reduction reaction (eCO2RR) to yield CH4 under neutral conditions. So far, most of the reported active sites for eCO2RR to yield CH4 are single metal sites; the performances are far below the commercial requirements. Herein, we reported a nanosheet metal-organic layer in single-layer, namely, [Cu2(obpy)2] (Cuobpy-SL, Hobpy = 1H-[2,2']bipyridinyl-6-one), possessing dicopper(I) sites for eCO2RR to yield CH4 in a neutral aqueous solution. Detailed examination of Cuobpy-SL revealed high performance for CH4 production with a faradic efficiency of 82(1)% and a current density of ∼90 mA cm-2 at -1.4 V vs. reversible hydrogen electrode (RHE). No obvious degradation was observed over 100 h of continuous operation, representing a remarkable performance to date. Mechanism studies showed that compared with the conventional single-copper sites and completely exposed dicopper(I) sites, the dicopper(I) sites in the confined space formed by the molecular stacking have a strong affinity to key C1 intermediates such as *CO, *CHO, and *CH2O to facilitate the CH4 production, yet inhibiting C-C coupling.

Lunar radiometric calibration is used to solve the problem of consistent radiometric calibration for multiple satellite platforms and remote sensors. However, the dark level will fluctuate when observing the Moon with the short-wave infrared spectrometer, which seriously affects the accuracy of the lunar radiation data. In this work, we proposed a dynamic spatial-time dark level correction approach to address the fluctuation of the dark level. This method employs the cold space signals in space and time dimensions to estimate the dark level for each frame individually and to reduce errors due to environmental variations. Experiments on lunar observations at multiple phase angles were conducted and the dark level correction results demonstrate that our proposed method is effective even in the short-wave infrared, and is also superior to currently existing techniques. For the single-band (1700 nm) image of the full moon, the mean background proportion of the proposed method is 1.00%, which is better than that of static dark correction method (2.25%) and linear dark correction method (5.93%).

The performance of photocatalysts is affected not only by the surface structure but also by the atomic arrangement of the subsurface. Guided by first-principle simulation, Pt(Pd) single atoms are introduced into hexagonal ZnIn2S4 to substitute the middle In site, and dual S vacancies in the vicinity of the dopant are subsequently created. This unique subsurface dopant-vacancy pair brings a new defect level and higher hole concentration, resulting in enhanced charge separation efficiency and superior electronic conductivity. More importantly, it could also modulate the p -band center of neighboring surface S atoms, thus optimizing the balance between H adsorption and desorption. As a consequence, the subsurface -engineered ZnIn2S4 delivers an H2 evolution rate of 165.4 mmol h-1 under visible-light irradiation, and a great number of H2 bubbles are released under natural solar light. This work provides a new perspective on the development of solar-to-H2 conversion through artful subsurface engineering.

Electroreduction of CO2 to acetate provides a promising strategy to reduce CO2 emissions and store renewable energy, but acetate is usually a by-product. Here, we show a stable and conductive two-dimensional phthalocyanine-based covalent-organic framework (COF) as an electrocatalyst for reduction of CO2 to acetate with a single-product Faradaic efficiency (FE) of 90.3(2)% at -0.8 V (vs. RHE) and a current density of 12.5 mA cm(-2) in 0.1 M KHCO3 solution. No obvious degradation was observed over 80 hours of continuous operation. Combined with the comparison of the properties of other catalysts with isolated metal active sites, theoretical calculations and in situ infrared spectroscopy revealed that the isolated copper-phthalocyanine active site with high electron density is conducive to the key step of C-C coupling of *CH3 with CO2 to produce acetate, and can avoid the coupling of *CO with *CO or *CHO to produce ethylene and ethanol.

Piezoelectric Micro machined Ultrasonic Transducer (PMUT) has been studied a lot in the past decades since the merit of easily integrating with IC to develop 2-D array for 3-D imaging applications. However, there are tremendous work and high costs in both time and investment to establish the final goal. In this paper, we propose a low cost approach to achieve 3-D imaging using two 1-D arrays by introducing binocular stereo vision method. The imaging system with two PMUTs is designed to conduct 3-D reconstruction of the vessel in vitro, and the flow velocity can be measured much more accurately comparing to traditional 2-D method. To decrease the requirement of imaging system, especially the number of independence T/R channels, B-mode imaging of the vessel is performed by analogy with Synthetic Aperture Focusing Technique (SAFT) technique. Two images in different directions are collected individually, and then combined and compensated into 3-D imaging. After that, the blood flow velocity is measured using pulsed Doppler. With the combination of 3-D imaging of the vessel and Doppler measurement, the position and morphology of vessel could be obtained, and then the flow velocity can be calculated accurately.

In situ transient synchrotron Laue x-ray diffraction based on high-energy and broadband x rays under high strain-rate tensile loading was developed at a superconducting wiggler beamline at the Beijing Synchrotron Radiation Facility. A split-Hopkinson tensile bar is utilized to realize this dynamic loading condition, while the transient Laue x-ray diffraction captures the transient internal structure of monocrystalline materials. Plastic deformation of a monocrystalline nickel specimen was investigated to prove the ability of this instrumentation in the characterization of a dynamic response of monocrystalline materials during a high strain-rate impact process with 5 µs time resolution.

Herein, a novel strategy has been proposed to design a hollow structure via post-modified N sites coordinating to metal species. As a result, an atomically dispersed Co site catalyst with high loading has been obtained and has shown superb performance in CO2 cycloaddition to ethylene carbonate. This novel avenue can be extended to other atomically dispersed metal catalysts with high loading.

To realize the long-period and automated data collection of lunar radiation and eliminate the geometric errors of the lunar hyperspectral image during the observation process, this paper proposes a slit-type spectrometer observation method based on the rotating table of the equatorial mount. This method uses a wide field finder-scope to realize automatic moon tracking and positioning; at the same time, it corrects the drift angle and oversampling of the collected raw data. The results show that the full moon situation is the same as the non-full moon situation. This method can effectively find and track the position of the moon's sphere center, and it also corrects the drift and over-sampling of the moon image, realizes accurate and automated long-term observation of the moon, reduces observation errors, and saves observation costs.