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A homopolymolybdate-supported plate-like 2D cobalt network constructed from a new pyrazole-amide-pyridyl ligand: highly electrochemical activity in both capacitive performance and the detection of Cr(Ⅵ)

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Tungsten 2024年第2期6卷 422-427页

作者： Xiu-li Wang Yong-zhen Chen Zhi-Han Chang Yu-chun lin Jing-Yi Ma College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Professional Technology Innovation Center of liaoning Province for Conversion Materials of Solar Cell Jinzhou 121013China

By employing a new semi-rigid pyrazole-amide-derived bis(pyridyl)ligand[N,N'-bis(4-picolylamine)-1-hydropyrazole(4-dpap)],a new homopolymolybdate-based two-dimensional(2D)plate-like complex[Co(4-dpap)(H_(2)O)(β-Mo_(8)O_(2)6)1/2](1)has been prepared under solvothermal condition and structurally characterized.Theβ-Mo_(8)anions are fi xed between the 2D metal–organic networks[Co(4-dpap)(H_(2)O)]n 2n+via hydrogen-bonding interaction.Complex 1 possesses satisfactory specifi c capacitance of 1512.4 F·g^(−1)(current density:1 A·g^(−1))and good cycling stability(90.8%after 1000 cycles).Moreover,1 represents a promising amperometric sensor for measurement of Cr(Ⅵ)with low detection limit(0.042μmol·L^(−1))and high durability.The insertion ofβ-Mo_(8)anions between the unique 2D metal−organic networks improves the active area of polyoxometalates,which further promotes electrochemical performance.

关键词： Homopolymolybdate Metal–organic network Pyrazole-amide-derived bis(pyridyl)ligand Supercapacitor Electrochemical sensor

Research progress on seismic imaging technology

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Petroleum Science 2022年第1期19卷 128-146页

作者： zhen-chun li Ying-Ming Qu School of Geosciences China University of PetroleumQingdaoShandong266580China Shandong Provincial Key Laboratory of Deep Oil&Gas China University of PetroleumQingdaoShandong266580China

High-precision seismic imaging is the core task of seismic exploration,guaranteeing the accuracy of geophysical and geological interpretation.With the development of seismic exploration,the targets become more and more complex.Imaging on complex media such as subsalt,small-scale,steeply dipping and surface topography structures brings a great challenge to imaging techniques.Therefore,the seismic imaging methods range from stacking-to migration-to inversion-based imaging,and the imaging accuracy is becoming increasingly high.This review paper includes:summarizing the development of the seismic imaging;overviewing the principles of three typical imaging methods,including common reflection surface(CRS)stack,migration-based Gaussian-beam migration(GBM)and reverse-time migration(RTM),and inversion-based least-squares reverse-time migration(LSRTM);analyzing the imaging capability of GBM,RTM and LSRTM to the special structures on three typical models and a land data set;outlooking the future perspectives of imaging methods.The main challenge of seismic imaging is to produce high-precision images for low-quality data,extremely deep reservoirs,and dual-complex structures.

关键词： Common reflection surface stack Gaussian-beam migration Reverse-time migration Least-squares reverse-time migration

Clinical analysis of secondary penile cancer:a case series at a tertiary referral center in China

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Asian Journal of Andrology 2024年第2期26卷 225-226页

作者： Xiao-Yu li chun-Ru Xu Xing Ji zhen-Peng Zhu zhen-Ke Guo Tian-Yu Cai Jian lin Department of Urology Peking University First HospitalBeijing 100034China Institute of Urology Peking UniversityBeijing 100034China National Urological Cancer Center Beijing 100034China Beijing Key Laboratory of Urogenital Diseases(Male)Molecular Diagnosis and Treatment Center Beijing 100034China

Dear Editor,Secondary penile cancer is an extremely rare condition that refers to the metastasis of other malignancies to the penis.There are limited reports on secondary penile cancer in Asian populations,and perceptions about this disease are extremely scarce.We reviewed and analyzed the data of patients diagnosed with secondary penile cancer based on the pathological findings at Peking University First Hospital in Beijing,China,aiming to expand the clinical reference for this rare disease.

关键词： cancer rare finding

Configuring single-layer MXene nanosheet onto natural wood fiber via C–Ti–C covalent bonds for high-stability li-S batteries

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Journal of Energy Chemistry 2024年第8期95卷 701-711页

作者： Yangyang Chen Yu liao Ying Wu Lei li zhen Zhang Sha Luo Yiqiang Wu Yan Qing College of Materials Science and Technology Central South University of Forestry and Technology

lithium-sulfur batteries（LSBs） are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and cost-effectiveness. However, the low conductivity and polysulfide shuttling effect of S cathodes severely hamper the practical performance of LSBs. Herein, in situ-generated single layer MXene nanosheet/hierarchical porous carbonized wood fiber（MX/PCWF） composites are prepared via a nonhazardous eutectic activation strategy coupled with pyrolysis-induced gas diffusion. The unique architecture, wherein single layer MXene nanosheets are constructed on carbonized wood fiber walls, ensures rapid polysulfide conversion and continuous electron transfer for redox reactions. The C–Ti–C bonds formed between MXene and PCWF can considerably expedite the conversion of polysulfides, effectively suppressing the shuttle effect. An impressive capacity of 1301.1 m A h g-1at 0.5 C accompanied by remarkable stability is attained with the MX/PCWF host, as evidenced by the capacity maintenance of 722.6 m A h g-1after 500 cycles. Notably, the MX/PCWF/S cathode can still deliver a high capacity of 886.8 m A h g-1at a high S loading of 5.6 mg cm-2.The construction of two-dimensional MXenes on natural wood fiber walls offers a competitive edge over S-based cathode materials and demonstrates a novel strategy for developing high-performance batteries.

关键词： C–Ti–C bonds lithium-sulfur batteries MXene nanosheets S cathodes Wood fiber

Prediction of contact resistance of electrical contact wear using different machine learning algorithms

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Friction 2024年第6期12卷 1250-1271页

作者： zhen-bing CAI chun-lin li Lei YOU Xu-dong CHEN li-ping HE Zhong-qing CAO Zhi-nan ZHANG Tribology Research Institute Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

H62 brass material is one of the important materials in the process of electrical energy transmission and signal transmission,and has excellent performance in all aspects.Since the wear behavior of electrical contact pairs is particularly complex when they are in service,we evaluated the effects of load,sliding velocity,displacement amplitude,current intensity,and surface roughness on the changes in contact resistance.Machine learning(ML)algorithms were used to predict the electrical contact performance of different factors after wear to determine the correlation between different factors and contact resistance.Random forest(RF),support vector regression(SVR)and BP neural network(BPNN)algorithms were used to establish RF,SVR and BPNN models,respectively,and the experimental data were trained and tested.It was proved that BP neural network model could better predict the stable mean resistance of H62 brass alloy after wear.Characteristic analysis shows that the load and current have great influence on the predicted electrical contact properties.The wear behavior of electrical contacts is influenced by factors such as load,sliding speed,displacement amplitude,current intensity,and surface roughness during operation.Machine learning algorithms can predict the electrical contact performance after wear caused by these factors.Experimental results indicate that an increase in load,current,and surface roughness leads to a decrease in stable mean resistance,while an increase in displacement amplitude and frequency results in an increase in stable mean resistance,leading to a decline in electrical contact performance.To reduce testing time and costs and quickly obtain the electrical contact performance of H62 brass alloy after wear caused by different factors,three algorithms(random forest(RF),support vector regression(SVR),and BP neural network(BPNN))were used to train and test experimental results,resulting in a machine learning model suitable for predicting the stable mean resistance of H62 brass alloy after wear.The pr

关键词： electrical contact wear contact resistance machine learning(ML) neural network

Management of triplet excitons transition:fine regulation of Förster and dexter energy transfer simultaneously

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light(Science & Applications) 2024年第2期13卷 302-315页

作者： Jiaqiang Wang Yujie Yang Xinnan Sun Xiaoning li liyao Zhang zhen li Institute of Molecular Aggregation Science Tianjin UniversityTianjin300072China School of life Sciences Tianjin UniversityTianjin300072China Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhan430072China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430072China Joint School of National University of Singapore Tianjin UniversityInternational Campus of Tianjin UniversityBinhai New CityFuzhou350207China

Understanding and management of triplet excitons transition in the same molecule remain a great challenge.Hence,for the first time,by host engineering,manageable transitions of triplet excitons in a naphthalimide derivative NDOH were achieved,and monitored through the intensity ratio(ITADF/IRTP)between thermally activated delayed fluorescence(TADF)and room-temperature phosphorescence(RTP).Energy differences between lowest triplet excited states of host and guest were changed from 0.03 to 0.17 eV,and ITADF/IRTP of NDOH decreased by 200 times,thus red shifting the afterglow color.It was proposed that shorter conjugation length led to larger band gaps of host materials,thus contributing to efficient Dexter and inefficient Förster energy transfer.Interestingly,no transition to singlet state and only strongest RTP with quantum yield of 13.9%could be observed,when PBNC with loosest stacking and largest band gap acted as host.This work provides novel insight for the management and prediction of triplet exciton transitions and the development of smart afterglow materials.

关键词： materials transition transitions

Layered niobium carbide enabling excellent kinetics and cycling stability of li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： li-Wen Lu Hui Luo Guang-Xu li Yun li Xin-Hua Wang Cun-Ke Huang Zhi-QiangLan Wen-zheng Zhou Jin Guo Mohammad Ismail Hai-zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State Key Laboratory of Featured Metal Materials and life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The li-Mg-B-H composite(2liBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage material.However,the slow kinetics and poor cycling stability severely restrict its practical applications.In this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the li-Mg-B-H composite.The milled 2liH+MgB_(2)composites were initially hydrogenated to obtain the 2liBH_(4)+MgH_(2)composites.The 2liBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2liBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and liBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2liBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th cycle.Nb_(2)C keeps stable in the composite and acts as an efficient catalyst for the li-Mg-B-H composite.It is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the li-Mg-B-H composite.This work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage lithium borohydride Magnesium hydride Nb_(2)C MXene

Efficacy and safety of Nafamostat mesylate in patients with endstage renal failure

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World Journal of Clinical Cases 2024年第1期12卷 68-75页

作者： Kun liu zhen-Hua li Department of Critical Care Medicine The Third People's Hospital Of Hubei ProvinceWuhan 430030Hubei ProvinceChina Department of Critical Care Medicine General Hospital of The Yangtze River ShippingWuhan Brain HospitalWuhan 430015Hubei ProvinceChina

BACKGROUND Recent studies on dialysis anticoagulation therapy in patients with renal failure have shown that Nafamostat mesylate,a broad-spectrum potent serine protease inhibitor,has strong anticoagulation and anti-fiber activity.AIM To evaluate the efficacy and safety of Nafamostat mesylate in patients with end-stage renal failure.METHODS Seventy-five patients with end-stage renal failure who received hemodialysis at our hospital between January 2020 and August 2021 were selected and divided into the observation group(Nafamostat mesylate for injection,n=33)and control group(heparin sodium injection,n=32).General patient data,indicators of clinical efficacy,dialyzer hemocoagulation parameters,coagulation function indices,and hemoglobin concentration and platelet count before and after treatment,and the occurrence of adverse reactions after treatment were compared between the two groups.RESULTS The two groups showed no significant differences in general patient data(P>0.05).The post-treatment effectiveness rate in the control group was lower than that in the observation group(P0.05),while the number of patients in grade 0 was lower in the control group,and the number of patients in grades II and III was higher in the control group(Plized ratio values in the control group were higher than those in the observation group,while the fibrinogen level in the control group was lower than that in the observation group(P0.05).The total number of post-treatment adverse reactions in the observation group was lower than that in the control group(P<0.05).CONCLUSION Treatment of patients showing end-stage renal failure with Nafamostat mesylate can significantly improve therapeutic efficacy and ha

关键词： End-stage renal failure Nafamostat mesylate Effectiveness Safety study Chronic kidney diseases

For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology

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China Communications 2024年第2期21卷 85-95页

作者： Chengjie li lidong Zhu zhen Zhang The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key Laboratory of Science and Technology on Communications(University of Electronic Science and Technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction