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High-Precision 2d-dOA Estimation Method for Millimeter-Wave radar Based on double-Parallel Linear Array and Joint IAA-rIT

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SENSOrS 2025年第8期25卷 2609-2609页

作者： Yu, danyang du, Lei Bai, Jie Chen, Yulin Natl Inst Metrol Div Mech & Acoust Metrol Beijing 100029 Peoples R China

High-precision two-dimensional direction of arrival (2d-dOA) estimation is an important mean of millimeter-wave radar for accurate target location. Aiming at the problems such as limited antenna aperture, signal coherence, and a few snapshots in millimeter-wave radar target detection, this paper proposes a 2d-dOA estimation method by using a joint iterative adaptive approach and rotational invariance technique (IAA-rIT) based on the double-parallel linear array. This method first constructs an iterative adaptive approach spectrum based on subarray 1 in the double-parallel linear array and then calculates the coupling angle estimate with the azimuth and the elevation. Secondly, based on the rotational invariance relationship between the two subarrays, the extended covariance matrices are respectively constructed, and the spatial smoothing technique is employed to decorrelate the signals. Then, the signal direction matrix is reconstructed based on the coupling angle estimate, and the rotational invariance relationship between the two subarrays is calculated to obtain another set of coupling angle estimates. Finally, the azimuth and the elevation are decoupled based on two sets of estimated coupling angles and the spatial geometry relation. Our experimental results show that IAA-rIT can estimate the coherent signal with high-precision 2d-dOA with a few snapshots and no additional angle matching.

关键词： millimeter-wave radar iterative adaptive approach rotational invariance technique double-parallel linear array a few snapshots signal coherence

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Molecular dynamics simulation of retention and bubble formation in tungsten with carbon impurities under high flux deuterium irradiation ∗

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JOUrNAL OF NUCLEAr MATErIALS 2025年 605卷

作者： Xiang, Yuan Shi, Liqun Zhang, Bin Fudan Univ Inst Modern Phys Shanghai 200433 Peoples R China

W is a critical plasma-facing material in fusion reactors. However, extreme conditions subject W to high-flux d plasma irradiation, resulting in d retention and bubble formation. Importantly, C impurities in the plasma can have a complex effect on d behavior in the W. due to experimental limitations, the impact of C on the evolution of irradiated W and the underlying mechanisms remains poorly understood. In this study, we employ molecular dynamics simulations to investigate the effects of C on the retention of d in W. The introduction forms of C include irradiation and direct doping. First, Irradiation can cause C to be retained, at the same time, the structure of W is severely damaged. W atoms in the subsurface are bombarded and displaced to form interstitial atoms and even be sputtered out of the W matrix. Statistical results show that the sputtering of W is primarily determined by the energy of impact C, with temperature having relatively minor effects. C irradiation forms a W-C mixed layer on the W surface. This layer has a disordered structure and is mixed with self-interstitial atoms and C atoms. d atoms incident from above are easily intercepted and captured by this layer and are difficult to migrate deeper. Second, C randomly doped in W significantly promotes the retention of d. The higher the C content, the higher the retention rate. Furthermore, the supersaturated accumulation of retained d leads to the formation of d bubbles. d undergoes an evolutionary process of forming molecules, clusters, and finally d bubbles. This work provides new insights into the W-C-d interaction mechanisms in fusion reactors, offering important theoretical support for the selection of W as a plasma-facing material.

关键词： Molecular dynamics simulation deuterium bubble Carbon deuterium retention Tungsten

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Structural Basis for Monomer-dimer Transition of dri1 Upon Heme Binding

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PrOTEINS-STrUCTUrE FUNCTION ANd BIOINFOrMATICS 2025年第5期93卷 949-956页

作者： Wang, Xiao-Ying Zhang, Jing Li, Hong-Yan dong, Chen-Song dai, Huai-En Wang, Mingzhu Liu, Lin Anhui Univ Sch Life Sci Hefei Anhui Peoples R China Anhui Univ Inst Phys Sci & Informat Technol Hefei Anhui Peoples R China

domain related to iron (drI) contains approximately 90 residues and is involved in iron and heme metabolism. recent discoveries have annotated dri1, a drI-only protein from the cyanobacterium Synechocystis, as a regulator of succinate dehydrogenase in a b-type heme-dependent manner or as a c-type heme oxygenase. Here, we report high-resolution structures of dri1 in complex with b-type and c-type hemes, respectively. Bis-His-ligated heme is located in the middle of the dimeric dri1 complex with heme b, as well as in the complex of monomeric dri1 with c-type heme, but distinct heme binding modes are revealed. Structural analyses suggest that dri1 may participate in the succinate dehydrogenase activity and/or the metabolism of cytochromes.

关键词： crystallography cyanobacteria heme binding heme c monomerization

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The mechanism of OEr activity and stability enhancement in acid by atomically doped iridium in γ-MnO2

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CHINESE JOUrNAL OF CATALYSIS 2025年 69卷 99-110页

作者： Sun, Yimeng Chen, Jun Liu, Lin Chi, Haibo Han, Hongxian Chinese Acad Sci Dalian Inst Chem Phys State Key Lab Catalysis Dalian Natl Lab Clean Energy Dalian 116023 Liaoning Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Univ Sci & Technol China Sch Chem & Mat Sci Hefei 230026 Anhui Peoples R China

Construction of iridium (Ir) based active sites on certain acid stable supports now is a general strategy for the development of low-Ir OEr catalysts. Atomically doped Ir in the lattice of acid stable gamma-MnO2 has been recently achieved, which shows high activity and stability though Ir usage was reduced more than 95% than that in current commercial proton exchange membrane water electrolyzer (PEMWE). However, the activity and stability enhancement by Ir doping in gamma-MnO2 still remains elusive. Herein, high dispersion of iridium (up to 1.37 atom%) doping in the lattice of gamma-MnO2 has been achieved by optimizing the thermal decomposition of the iridium precursors. Benefiting from atomic dispersive doping of Ir, the optimized Ir-MnO2 catalyst shows high OEr activity, as it has turnover frequency of 0.655 s-1 at an overpotential of 300 mV in 0.5 mol L-1 H2SO4. The catalyst also shows high stability, as it can sustainably work at 100 mA cm-2 for 24 h. Experimental and theoretical studies reveal that Ir is preferentially doped into ,fl phase rather than r phase, and the Ir site is the active site for OEr. The OEr active site is postulated to be Ir5+-O(H)-Mn3+ unit structure on the surface. Furthermore, Ir doping changes the potential determining step from the formation of O* to the formation of *OOH, emphasizing the promoting effect toward OEr derived from Ir sites. This work not only demonstrates the possibility of achieving atomic-level doping of Ir on the surface of a support to dramatically reduce Ir usage, but also, more importantly, reveals the mechanism behind accounting for the stability and activity enhancement by Ir doping. These important findings may serve as valuable guidance for further development of more efficient, stable and cost-effective low Ir-based OEr catalysts for PEMWE. Published by Elsevier B.V. All rights reserved.

关键词： Acidic oxygen evolution reaction Low-iridium Mn-based oxides Proton exchange membrane water electrolysis Green hydrogen

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Infrared emission of polycyclic aromatic hydrocarbon molecules in Titan: Cyanonaphthalenes

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MONTHLY NOTICES OF THE rOYAL ASTrONOMICAL SOCIETY 2025年第2期539卷 771-775页

作者： Zhou, Li Li, Kaijun Li, Aigen Zhou, Zheng Nanchang Univ Dept Chem Nanchang 330031 Peoples R China Univ Missouri Dept Phys & Astron Columbia MO 65211 USA Xiangtan Univ Hunan Key Lab Stellar & Interstellar Phys Xiangtan 411105 Hunan Peoples R China Xiangtan Univ Sch Phys & Optoelect Xiangtan 411105 Hunan Peoples R China John L Miller Great Neck North High Sch Great Neck NY 11023 USA

As the only moon in the Solar system with a thick atmosphere, Titan is a compelling and enigmatic world containing a complex organic haze. Polycyclic aromatic hydrocarbon (PAH) molecules are believed to play an essential role in the formation of Titan's aerosols and haze layers. The existence of PAHs in Titan's upper atmosphere has been revealed by the detection of the 3.28 mu m emission band with Cassini's Visual and Infrared Mapping Spectrometer (VIMS). However, there is little knowledge about the identity, composition, size, and abundance of PAH molecules in Titan's atmosphere. due to its unprecedented sensitivity and spectral coverage and resolution, the advent of the JWST could possibly enable a full characterization of the chemical makeups of Titan's aerosols. In particular, with a much better spectral resolution than Cassini's VIMS, JWST's Near Infrared Spectrograph (and Mid-Infrared Instrument ) could enable the spectral bands to be better resolved, potentially providing crucial information about which PAHs are really present in Titan's upper atmosphere. To facilitate JWST to search for and identify Titan's PAH molecules, we are performing a systematic study of the photophysics of PAHs in Titan's upper atmosphere. As a pilot study, here we report the infrared emission spectra of vibrationally excited cyanonapthalenes and their ions, which are composed of two fused benzene rings and one nitrile (-CN) group. The calculated emission spectra will help JWST to quantitatively determine or place an upper limit on the abundances of cyanonapthalenes in Titan's upper atmosphere.

关键词： astrochemistry infrared: planetary system planets and satellites: composition planets and satellites: individual: Titan

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Gravitational waves and primordial black holes from axion domain walls in level crossing

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Chinese Physics C 2025年第3期49卷 171-180页

作者： Hai-Jun Li Yu-Feng Zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

In this paper,we investigate the nano-Hertz gravitational wave(GW)emission and massive primordial black hole(PBH)formation from the light QCd axion *** consider the axion domain wall formation from the level crossing induced by the mass mixing between the light Z_(N)QCd axion and axion-like particle.A general mixing case in which the heavy and light mass eigenvalues do not necessarily have to coincide with the axion masses is *** form the domain walls,the axions should start to oscillate slightly before the level *** domain walls must annihilate before dominating the Universe to avoid cosmological ***,we focus our attention on the GW emission from the domain wall annihilation and the PBH formation from the domain wall *** show the predicted GW spectra with a peak frequency~0.2 nHz and peak amplitude~5×10^(-9),which can be tested by future pulsar timing array *** addition,during the domain wall annihilation,the closed walls could shrink to the Schwarzschild radius and collapse into the *** find that PBHs in the mass range of O(10^(5)-10^(8))M_(⊙)could potentially form in this scenario and account for a small fraction(~10^(-5))of the cold dark matter.

关键词： gravitational waves primordial black holes QCd axion

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resonantly Enhanced Hybrid Wannier-Mott-Frenkel Excitons in Organic-Inorganic Van der Waals Heterostructures

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AdVANCEd MATErIALS 2025年第8期37卷 e2411972页

作者： Fu, Shaohua ding, Jianwei Lv, Haifeng Zheng, Yue Liu, Shuangyan Zhao, Kun Bai, Zhiying Shi, Yumeng He, dawei Wang, rui Zhao, Jimin Wu, Xiaojun Tang, dongsheng Qiu, Xiaohui Wang, Yongsheng Zhang, Xiaoxian Beijing Jiaotong Univ Inst Optoelect Technol Key Lab Luminescence & Opt Informat Minist Educ Beijing 100044 Peoples R China Hunan Normal Univ Synerget Innovat Ctr Quantum Effects & Applicat Sch Phys & Elect Key Lab Low Dimens Quantum Struct & Quantum Contro Changsha 410081 Peoples R China Natl Ctr Nanosci & Technol CAS Ctr Excellence Nanosci CAS Key Lab Standardizat & Measurement Nanotechnol Beijing 100190 Peoples R China SUNY Stony Brook Dept Phys & Astron Stony Brook NY 11794 USA Univ Chinese Acad Sci Beijing 100049 Peoples R China Univ Sci & Technol China Hefei Natl Lab Phys Sci Microscale Synerget Innovat Ctr Quantum Informat & Quantum Te CAS Key Lab Mat Energy ConversSch Chem & Mat Sci Hefei 230026 Anhui Peoples R China Univ Sci & Technol China CAS Ctr Excellence Nanosci Hefei 230026 Anhui Peoples R China Shenzhen Univ Inst Microscale Optoelect Int Collaborat Lab 2D Mat Optoelect Sci & Technol Minist Educ Shenzhen 518060 Peoples R China Beijing Informat Technol Coll Beijing 100015 Peoples R China Chinese Acad Sci Beijing Natl Lab Condensed Matter Phys Inst Phys Beijing 100190 Peoples R China

Hybrid excitons formed via resonant hybridization in 2d material heterostructures feature both large optical and electrical dipoles, providing a promising platform for many-body exciton physics and correlated electronic states. However, hybrid excitons at organic-inorganic interface combining the advantages of both Wannier-Mott and Frenkel excitons remain elusive. Here, hybrid excitons are reported in the copper phthalocyanine/molybdenum diselenide (CuPc/MoSe2) heterostructure (HS) featuring strong molecular orientation dependence by low-temperature photoluminescence and absorption spectroscopy. The hybrid Wannier-Mott-Frenkel excitons exhibit a large oscillator strength and display signatures of the Frenkel excitons in CuPc and the Wannier-Mott excitons in MoSe2 simultaneously through the delocalized electrons. The density functional theory (dFT) calculations further confirm the strong hybridization between the lowest unoccupied molecular orbital (LUMO) of CuPc and the conduction band minimum (CBM) of MoSe2. The out-of-plane molecular orientation is further employed to tune the hybridization strength and tailor the hybrid exciton states. The results reveal the hybrid excitons at the CuPc/MoSe2 interface with tunability by molecular orientation, suggesting that the organic-inorganic HS constitutes a promising platform for many-body exciton physics such as exciton condensation and optoelectrical applications.

关键词： hybrid exciton interfacial coupling low-temperature photoluminescence molecular orientation organic-inorganic heterostructure

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development and application of a coal quality intelligent inspection system based on NIrS-XrF technology

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JOUrNAL OF ANALYTICAL ATOMIC SPECTrOMETrY 2025年第4期40卷 1069-1085页

作者： Gao, rui Li, Jiaxuan Han, Hongzhi Song, Jianchao Huo, Jiongyu dong, Lei Ma, Weiguang Wang, Shuqing Zhang, Yan Zhang, Lei Zhang, Peihua Ye, Zefu Zhu, Zhujun Zhao, Yang Yin, Wangbao Jia, Suotang Shanxi Univ Inst Laser Spect State Key Lab Quantum Opt Technol & Devices Taiyuan 030006 Peoples R China Shanxi Univ Collaborat Innovat Ctr Extreme Opt Taiyuan 030006 Peoples R China Sinopec Res Inst Petr Proc Co Ltd Beijing 100083 Peoples R China Xian Technol Univ Sch Optoelect Engn Xian 710021 Peoples R China Shanxi Gemeng US China Clean Energy R&D Ctr Co Ltd Taiyuan 030032 Peoples R China North Univ China Sch Semicond & Phys Taiyuan 030051 Peoples R China

As an important component of industrialization, coking plants require high-quality coking coal. Traditional coal quality analysis methods are cumbersome and inefficient, allowing inferior coal to enter production. In this study, a coal quality intelligent inspection system is developed by combining a fully automatic sampling unit and an analysis control platform, realizing a closed-loop, unmanned process for coal collection, preparation, measurement, and storage, enabling rapid detection of industrial indicators of coal, ensuring every truck's coal quality, distinguishing genuine from fake, and enhancing the ability of coking plants to identify inferior coal. Technologically, we adopt the NIrS-XrF dual-spectral coal quality analysis technique, which combines near-infrared spectroscopy (NIrS) and X-ray fluorescence spectroscopy (XrF). This technique uses NIrS to efficiently and reliably detect organic groups in coal and XrF to accurately and reliably measure inorganic ash-forming components and sulfur elements;consequently, it enables the simultaneous and precise measurement of key indicators such as ash content, volatile matter, and sulfur content in coal. In terms of modeling strategy, we employ a multi-modeling approach to address the complex relationships between different coal quality indicators and spectra, as well as the matrix effects among different coal types. Through analysis and research on different partial least squares regression (PLSr) modeling strategies, we selected the optimal prediction models for each indicator to ensure the accuracy and reliability of the system monitoring results. Specifically, we achieved favorable prediction results for ash content and volatile matter through subtype modeling, while sulfur content attained high accuracy through holistic-segmented modeling, with coefficients of determination (r2) of 0.97, 0.94, and 0.97, respectively, root mean square errors of prediction (rMSEPs) of 0.29%, 0.92%, and 0.06%, respectively, aver

关键词： Near infrared spectroscopy

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Soil Acidification destabilizes Terrestrial Ecosystems via decoupling Soil Microbiome

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GLOBAL CHANGE BIOLOGY 2025年第4期31卷 e70174页

作者： duan, Yulong Zhang, Junbiao Petropoulos, Evangelos Zhao, Jianhua Jia, rongliang Wu, Fasi Chen, Yun Wang, Lilong Wang, Xuyang Li, Yulin Li, Yuqiang Chinese Acad Sci Northwest Inst Ecoenvironm & Resources Key Lab Ecol Safety & Sustainable Dev Arid Lands Lanzhou Peoples R China Chinese Acad Sci Naiman Desertificat Res Stn Northwest Inst Ecoenvironm & Resources Tongliao Peoples R China Univ Chinese Acad Sci Beijing Peoples R China Shanghai Majorbio Biopharm Technol Co Ltd Shanghai Peoples R China Stantec UK Ltd Newcastle Upon Tyne England Chinese Acad Sci Shapotou Desert Res & Expt Stn Northwest Inst Ecoenvironm & Resources Zhongwei Peoples R China Dunhuang Acad Natl Res Ctr Conservat Ancient Wall Paintings & Ea Dunhuang Gansu Peoples R China

Soil microbiome is essential for terrestrial ecosystem preservation. beta-diversity information on the former, although dynamic due to its sensitivity to environmental conditions driven by climate change, is limited. Our knowledge becomes poorer for microbiomes subjected to environmental gradients, especially for those across multiple ecosystems-information important for biological conservation management. In this study, using next generation sequencing and machine learning at samples from 207 locations among 4300 km of transects that spanned among six typical terrestrial ecosystems of china, we established the divergent distance-decay relationships between bacterial and eukaryotic communities in response to soil pH (pH as proxy of climate and edaphic conditions). The findings, pH-decrease results in lower beta-diversity (convergent tendency) among the bacterial communities opposite to the eukaryotic ones (low pH-high beta-diversity (divergent tendency)). Meanwhile, competition between bacteria and eukaryotes intensifies at lower pH while the predominant genera and communities are re-structured. Under these circumstances, potential soil acidification due to climate change or other factors could alter soil bacteria and eukaryotes into decoupling directions influencing ecosystems' stability. Thus, soil pH is a pivotal environmental variable that not only describes, but also controls, soil microbiome dynamics at a large scale under ongoing global changes;hence, a cornerstone variable for the biodiversity conservation of china's nature protected areas and not only.

关键词： alpha-diversity beta-diversity bacteria biodiversity conservation eukaryota protected areas

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Simultaneous Profiling of Multiple Phosphorylated Metabolites in Typical Biological Matrices via Ion-Pair reversed-Phase Ultrahigh-Performance Liquid Chromatography and Mass Spectrometry

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ANALYTICAL CHEMISTrY 2025年第3期97卷 1681-1687页

作者： Wang, Huan Chen, Qinsheng Wu, Yuanpeng Xu, Li Wang, Qi Hu, Qingyu Tang, Huiru Fudan Univ State Key Lab Genet Engn Sch Life Sci Human Phenome InstZhangjiang Fudan Int Innovat Ct Shanghai 200032 Peoples R China

Simultaneous analysis of multiple phosphorylated metabolites (phosphorylated metabolome) in biological samples is vital to reveal their physiological and pathophysiological functions, which is extremely challenging due to their low abundance in some biological matrices, high hydrophilicity, and poor chromatographic behavior. Here, we developed a new method with ion-pair reversed-phase ultrahigh-performance liquid chromatography and mass spectrometry using BEH C18 columns modified with hybrid surface technology. This method demonstrated good performances for various phosphorylated metabolites, including phosphorylated sugars and amino acids, nucleotides, NAd-based cofactors, and acyl-CoAs in a single run using standard LC systems. Specifically, the method showed good retention (capacity factor > 2) and reproducibility (delta t r < 0.09 min, n = 6), peak symmetry (tailing factor < 2), and sensitivity (limit-of-detection < 238 fmol-on-column with QTOFMS) for all tested analytes especially for the medium- and/or long-chain acyl-CoAs. The method demonstrated reproducible applicability across numerous biological matrices, including tissue (liver), human biofluids (urine, plasma), cells, and feces, and revealed significant molecular phenotypic differences in phosphorylated metabolite composition.

关键词： Metabolites

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