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Insights into host-guest interactions and enhanced MRI contrast applications of water-soluble tetrahedral metal-organic cages

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science China Chemistry 2025年

作者： Yu-Xiao Chen Mao-Song Qiu Jie-Sheng Hu Hua-Liang Yue Meng Yu Shi-Zhen Chen Xin Zhou Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical Engineering Beijing Institute of Technology State Key Laboratory of Magnetic Resonance Spectroscopy and Imaging National Center for Magnetic Resonance in Wuhan Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences University of Chinese Academy of Sciences School of Biomedical Engineering Hainan University

Metal-organic cages （MOCs） are emerging as pivotal components in the design of innovative magnetic resonance imaging （MRI）contrast *** study introduces a novel,water-soluble metal-organic cage,K12[Fe4L4],synthesized using a co-planar triangular ligand,N-{4-[4,6-bis(4-{[（2,3-dihydroxyphenyl）carbonyl]amino}phenyl)-1,3,5-triazin-2-yl]phenyl}-2,3-dihydroxybenzamide （H6L）.This cage represents the first instance of a gadolinium（Ⅲ）-free M4L4structure optimized for T1-weighted *** provide a detailed analysis of its structural attributes,aqueous stability,magnetic properties,and host-guest *** evaluations in vitro reveal that K12[Fe4L4]significantly elevates the longitudinal relaxivity of water protons,achieving a relaxivity of 5.41 mM-1s-1at 33°C and 0.5 *** enhancement increases to 9.24 mM-1s-1in the presence of human serum albumin （HSA）,indicating potent interaction dynamics with binding constant （Ka） of （6.1±1.4）×10～*** studies highlight that even at low doses of 0.010 mmol kg-1,K12[Fe4L4]surpasses the imaging efficacy of the commercial agent ProHance,while also demonstrating prolonged in vivo retention suitable for extended diagnostic *** findings not only underscore the utility of M4L4cages in T1-weighted MRI but also lay foundational insights for the development of multinuclear,gadolinium（Ⅲ）-free contrast agents,paving the way for safer and more effective diagnostic imaging solutions.

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Doping-enhanced robustness of anomaly-related magnetoresistance in WTe_(2±α)flakes

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Chinese Physics B 2023年第4期32卷 634-638页

作者：孟建超陈鑫祥邵婷娜刘明睿姜伟民张子涛熊昌民窦瑞芬聂家财 Department of Physics Beijing Normal UniversityBeijing 100875China College of Science Inner Mongolia University of TechnologyHohhot 010051China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

We study systematically the negative magnetoresistance(MR)effect in WTe_(2±α)flakes with different thicknesses and doping *** negative MR is sensitive to the relative orientation between electrical-/magnetic-field and crystallographic orientation of WTe_(2±α).The analysis proves that the negative MR originates from chiral anomaly and is *** entropy mobility spectrum is used to analyze the electron and hole concentrations in the flake *** is found that the negative MR observed in WTe_(2±α)flakes with low doping concentration is small,and the high doping concentration is *** doping-induced disorder obviously inhibits the positive MR,so the negative MR can be more easily *** a word,we introduce disorder to suppress positive MR by doping,and successfully obtain the negative MR in WTe_(2±α)flakes with different thicknesses and doping concentrations,which indicates that the chiral anomaly effect in WTe_(2)is robust.

关键词： Weyl semimetal WTe_(2±α)flakes doping chiral anomaly robustness

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Noise reduction and periodic signal extraction for GNSS height data in the study of vertical deformation

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Geodesy and Geodynamics 2023年第6期14卷 573-581页

作者： Jingqi Wang Kaihua Ding Heping Sun Geng Zhang Xiaodong Chen School of Geography and Information Engineering China University of GeosciencesWuhan 430074China State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China University of Chinese Academy of Sciences Beijing 100049China

Global navigation satellite system(GNSS)technique has irreplaceable advantages in the continuous monitoring of surface *** noise to improve the signal-to-noise ratio(SNR)and extract the concerned signals is of great *** an improved algorithm of empirical mode decomposition(EMD),complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN)algorithm has better signal processing *** the CEEMDAN algorithm,the height time series of 29GNSS stations in Chinese mainland were analyzed,and good denoising effects and extraction from periodic signals were *** numerical results showed that the annual signal obtained with the CEEMDAN algorithm was significantly based on Lomb_Scargle spectrum analysis,and large differences in the long-term signals were found between the stations at different locations in Chinese *** respect to data denoising,compared with the EMD and wavelet denoising algorithms,the CEEMDAN algorithm respectively improved the SNR by 29.35% and 36.54%,increased the correlation coefficient by 8.67% and 11.96%,and reduced root mean square error(RMSE)by 44.68% and 43.48%,indicating that the CEEMDAN algorithm had better denoising behavior than the other two *** addition,the results demonstrated that different denoising methods had little influence on estimating the annual vertical deformation *** extraction of periodic signals showed that more components were retained by using the CEEMDAN algorithm than the EMD algorithm,which indicated that the CEEMDAN algorithm had advantages over frequency *** conclusion,the CEEMDAN algorithm was recommended for processing the GNSS height time series to analyze the vertical deformation due to its excellent features of denoising and the extraction of periodic signals.

关键词： Vertical surface deformation GNSS height time series CEEMDAN Denoising Periodic signal extraction

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Oyster studies reveal the duplication and functional diversification of Bivalvia caspase-8 genes

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Journal of Oceanology and Limnology 2023年第3期41卷 1109-1121页

作者： Shaoxi DENG Tao QU Guofan ZHANG Fei XU CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266000China NHC Key Laboratory of Diagnosis and Therapy of Gastrointestinal Tumor Gansu Provincial HospitalLanzhou 730000China

Caspase-8,first classified as a pro-apoptotic caspase,is considered to have arisen from duplication with caspase-10 and involves multiple immune and inflammatory responses in ***,few are known on the phylogeny and function of caspase-8 in molluscs,one of the largest phyla in marine *** this study,we conducted phylogenetic and functional analysis on molluscan caspase-8-like *** indicate that duplication occurred in molluscan caspase-8-like genes,resulting in at least two caspase-8 copies in some groups of *** studies in Pacific oyster Crassostrea gigas showed different spatio-temporal expression patterns and subcellular localizations of CgCaspase-8-1 and *** no interaction was observed between CgCaspase-8-2 and CgFADD,the adaptor molecule in apoptosis,yeast two-hybrid and co-immunoprecipitation assays suggested the interaction between CgCaspase-8-1 and CgFADD,indicating its pro-apoptotic *** addition,CgCaspase-8-1 showed interaction with the CARD domain of *** with two NF-κB subunits(Cgp105 and CgRel),their transcripts were up-regulated in response to poly(I:C)stimuli,supporting the immune function of both pro-and *** results provide insight into the evolution and functional diversification of Bivalvia caspase-8 genes.

关键词： caspase-8 apoptosis metamorphosis inflammation Crassostrea gigas

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The Porous Nanocarbons with Polynuclear Aromatic Cores

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CCS Chemistry 2024年第10期6卷 2427-2438页

作者： Chenxi Zhou Ruoning Li Yan Chen Xinyue Liu Haisong Zhao Xue-Qing Yang Zhongjie Ren Dong Wang Zhaohui Wang Lei Zhang Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Lab of Organic-Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029 CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100190 Key Laboratory of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084

Three porous nanocarbons,1–3 that comprise pyrene,corannulene,and coronene cores encircled by cyclo-meta-phenylene(CMP)interconnections,have been synthesized and *** interconnected CMPs caused different curvatures of the cores and imparted high solubility,large bathochromic shift,strong fluorescence,and low reduction potential to the *** solution,these porous nanocarbons existed as a complex mixture of dynamic processes that certainly influenced one another within any single molecule,leading to a set of rather simple proton nuclear magnetic resonance(^(1)H NMR)*** crystal X-ray diffraction and computational minimum energy analysis revealed the boatand saddle-like conformations of 1–3 in the solid state,significantly deviating from their conformations on the Au(111)***,both 1 and 2 could form 2:1 complexes with C_(60),accompanied by adaptive geometry *** addition,1 served as a sky-blue emitter for an organic light-emitting diode(OLED).This work gives access and insights into a model system consisting of porous nanocarbons with intriguing supramolecular and optoelectronic properties.

关键词： porous nanocarbon cyclophenylenes aromatic core structural dynamics crystal packing

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Valence electronic engineering of superhydrophilic Dy-evoked Ni-MOF outperforming RuO_(2) for highly efficient electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2024年第3期90卷 244-252,I0007页

作者： Zhiyang Huang Miao Liao Shifan Zhang Lixia Wang Mingcheng Gao Zuyang Luo Tayirjan Taylor Isimjan Bao Wang Xiulin Yang Guangxi Key Laboratory of Low Carbon Energy Materials School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGulin 541004GuangxiChina State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Saudi Arabia Basic Industries Corporation(SABIC)at King Abdullah University of Science and Technology(KAUST) Thuwal 23955-6900Saudi Arabia

Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) ***,we introduce a novel strategy of dysprosium(Dy) doping,using the unique 4f orbitals of this rare earth element to enhance electrocatalytic activity of *** method involves constructing Dy-doped Ni-MOF(Dy@Ni-MOF) nanoneedles on carbon cloth via a Dy-induced valence electronic perturbation *** and density functional theory(DFT) calculations reveal that Dy doping can effectively modify the electronic structure of the Ni active centers and foster a strong electronic interaction between Ni and *** resulting benefits include a reduced work function and a closer proximity of the d-band center to the Fermi level,which is conducive to improving electrical conductivity and promoting the adsorption of oxygen-containing ***,the Dy@Ni-MOF achieves superhydrophilicity,ensuring effective electrolyte contact and thus accelerating reaction kinetics,Ex-situ and in-situ analysis results manifest Dy_(2)O_(3)/NiOOH as the actual active ***,Dy@Ni-MOF shows impressive OER performance,significantly surpassing ***,the overall water splitting device with Dy@NiMOF as an anode delivers a low cell voltage of 1.51 V at 10 mA cm^(-2) and demonstrates long-term stability for 100 h,positioning it as a promising substitute for precious metal catalysts.

关键词： Dy@Ni-MOF Dy incorporation Electronic interaction Superhydrophilicity Oxygen evolution reaction

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Squeezing More Past Knowledge for Online Class-Incremental Continual Learning

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 722-736页

作者： Da Yu Mingyi Zhang Mantian Li Fusheng Zha Junge Zhang Lining Sun Kaiqi Huang the State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150080China Center for Research on Intelligent System and Engineering Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190 School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Center for Research on Intelligent System and Engineering Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190the School of Artificial IntelligenceUniversity of Chinese Academy of SciencesBeijing 100049 the CAS Center for Excellence in Brain Science and Intelligence Technology Shanghai 200031China IEEE

Continual learning(CL)studies the problem of learning to accumulate knowledge over time from a stream of data.A crucial challenge is that neural networks suffer from performance degradation on previously seen data,known as catastrophic forgetting,due to allowing parameter *** this work,we consider a more practical online class-incremental CL setting,where the model learns new samples in an online manner and may continuously experience new ***,prior knowledge is unavailable during training and *** works usually explore sample usages from a single dimension,which ignores a lot of valuable supervisory *** better tackle the setting,we propose a novel replay-based CL method,which leverages multi-level representations produced by the intermediate process of training samples for replay and strengthens supervision to consolidate previous ***,besides the previous raw samples,we store the corresponding logits and features in the ***,to imitate the prediction of the past model,we construct extra constraints by leveraging multi-level information stored in the *** the same number of samples for replay,our method can use more past knowledge to prevent *** conduct extensive evaluations on several popular CL datasets,and experiments show that our method consistently outperforms state-of-the-art methods with various sizes of episodic *** further provide a detailed analysis of these results and demonstrate that our method is more viable in practical scenarios.

关键词： Catastrophic forgetting class-incremental learning continual learning(CL) experience replay

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Narrowband Tunable Optical Filter with An Arch-Like Configuration Using SOI Platform 6

Narrowband Tunable Optical Filter with An Arch-Like Configur...

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6th IEEE International Conference on Electronic Information and Communication technology, ICEICT 2023

作者： Wang, Haoyan Ye, Yunong Li, Wei Wang, Zhiqiang Liu, Jie Zhang, Lei Information Science Academy China Electronics Technology Group Corporation Beijing China University of Electronic Science and Technology of China Chengdu China Chinese Academy of Sciences State Key Laboratory of Integrated Optoelectronics Institute of Semiconductors Beijing China

ISBN: (纸本)9798350399059

We propose and demonstrate a low-loss optical bandpass filter with a narrow bandwidth and a steep roll-off, which is based on three feed-forward silicon microring resonators (MRRs). Using the scattering matrix method, we elaborate the simulation model and spectral response analysis of our proposed filter, thereby determining the geometric parameters of the proposed optical filter. Moreover, we compare its performance with different MRR-based filters composed of three ring cavities. Our proposed filter exhibits a different spectral line shape, lower insertion loss and a distinct roll-off feature for the same target 3dB bandwidth. As a proof of concept, we fabricate the proposed optical filter on a silicon-on-insulator (SOI) platform. The device exhibits a 3dB bandwidth of ∼ 25 GHz @1550nm and an on-chip loss of -2.5 dB. Additionally, at the transition band points -10 dB and -20 dB lower than the passband center, we observe a roll-off rate of ∼ 45 dB/nm. Compared with traditional high-order MRRs, our scheme has lower fabrication accuracy requirements and produces lower thermal crosstalk. © 2023 IEEE.

关键词： Optical filters

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Improving Satellite-Retrieved Cloud Base Height with Ground-Based Cloud Radar Measurements

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Advances in Atmospheric sciences 2024年第11期41卷 2131-2140页

作者： Zhonghui TAN Ju WANG Jianping GUO Chao LIU Miao ZHANG Shuo MA College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration School of Atmospheric PhysicsNanjing University of Information Science&TechnologyNanjing 210044China National Satellite Meteorological Center(National Center for Space Weather) China Meteorological AdministrationBeijing 100081China

Cloud base height(CBH) is a crucial parameter for cloud radiative effect estimates, climate change simulations, and aviation guidance. However, due to the limited information on cloud vertical structures included in passive satellite radiometer observations, few operational satellite CBH products are currently available. This study presents a new method for retrieving CBH from satellite radiometers. The method first uses the combined measurements of satellite radiometers and ground-based cloud radars to develop a lookup table(LUT) of effective cloud water content(ECWC), representing the vertically varying cloud water content. This LUT allows for the conversion of cloud water path to cloud geometric thickness(CGT), enabling the estimation of CBH as the difference between cloud top height and CGT. Detailed comparative analysis of CBH estimates from the state-of-the-art ECWC LUT are conducted against four ground-based millimeter-wave cloud radar(MMCR) measurements, and results show that the mean bias(correlation coefficient) is0.18±1.79 km(0.73), which is lower(higher) than 0.23±2.11 km(0.67) as derived from the combined measurements of satellite radiometers and satellite radar-lidar(i.e., Cloud Sat and CALIPSO). Furthermore, the percentages of the CBH biases within 250 m increase by 5% to 10%, which varies by location. This indicates that the CBH estimates from our algorithm are more consistent with ground-based MMCR measurements. Therefore, this algorithm shows great potential for further improvement of the CBH retrievals as ground-based MMCR are being increasingly included in global surface meteorological observing networks, and the improved CBH retrievals will contribute to better cloud radiative effect estimates.

关键词： cloud base height passive radiometer ground-based cloud radar remote sensing

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Revealing interfacial charge redistribution of homologous Ru-RuS_(2) heterostructure toward robust hydrogen oxidation reaction

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Journal of Energy Chemistry 2024年第7期94卷 332-339页

作者： Yi Liu Lianrui Cheng Shuqing Zhou Yuting Yang Chenggong Niu Tayirjan Taylor Isimjan Bao Wang Xiulin Yang Guangxi Key Laboratory of Low Carbon Energy Materials School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004GuangxiChina State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Saudi Arabia Basic Industries Corporation(SABIC)at King Abdullah University of Science and Technology(KAUST) Thuwal 23955-6900Saudi Arabia

Precisely tailoring the surface electronic structures of electrocatalysts for optimal hydrogen binding energy and hydroxide binding energy is vital to improve the sluggish kinetics of hydrogen oxidation reac-tion(HOR).Herein,we employ a partial desulfurization strategy to construct a homologous Ru-RuS_(2) heterostructure anchored on hollow mesoporous carbon nanospheres(Ru-RuS_(2)@C).The disparate work functions of the heterostructure contribute to the spontaneous formation of a unique built-in electric field,accelerating charge transfer and boosting conductivity of ***,Ru-RuS_(2)@C exhibits robust HOR electrocatalytic activity,achieving an exchange current density and mass activity as high as 3.56 mA cm^(-2) and 2.13 mAμg_(Ru)^(-1),*** those of state-of-the-art Pt/C and most contemporary Ru-based HOR ***,Ru-RuS_(2)@C can tolerate 1000 ppm of cO that lacks in Pt/*** analysis reveals that the directional electron transfer across Ru-RuS_(2) heterointerface induces local charge redistribution in interfacial region,which optimizes and balances the adsorption energies of H and OH species,as well as lowers the energy barrier for water formation,thereby promoting theHoR performance.

关键词： Heterostructure Hollow spherical structure Hydrogen oxidation reaction Charge redistribution Density functional calculation

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