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Bimetallic CoNi single atoms supported on three-dimensionally ordered mesoporous chromia: highly active catalysts for n-hexane combustion

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Green Energy & Environment 2024年第7期9卷 1122-1137页

作者： Xiuqing Hao Yuxi Liu Jiguang deng Lin Jing jia Wang Wenbo pei Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution Control Key Laboratory of Advanced Functional Materials Education Ministry of China Laboratory of Catalysis Chemistry and Nanoscience Department of Chemical Engineering Faculty of Environment and Life Beijing University of Technology

Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile organic compounds （VOCs）.In this work,we prepared the mesoporous chromia-supported bimetallic Co and Ni single-atom （Co1Ni1/meso-Cr2O3） and bimetallic Co and Ni nanoparticle (CoNPNiNP/mesoCr2O3) catalysts adopting the one-pot polyvinyl pyrrolidone （PVP）-and polyvinyl alcohol （PVA）-protecting approaches,*** results indicate that the Co1Ni1/meso-Cr2O3catalyst exhibited the best catalytic activity for n-hexane (C6H14) combustion (T50%and T90%were 239 and 263℃ at a space velocity of 40,000 mL g-1h-1;apparent activation energy and specific reaction rate at 260℃ were 54.7 kJ mol-1and 4.3×10-7mol g-1cats-1,respectively),which was associated with its higher (Cr5++Cr6+) amount,large n-hexane adsorption capacity,and good lattice oxygen mobility that could enhance the deep oxidation of n-hexane,in which Ni1was beneficial for the enhancements in surface lattice oxygen mobility and low-temperature reducibility,while Co1preferred to generate higher contents of the high-valence states of chromium and surface oxygen species as well as adsorption and activation of n-hexane.n-Hexane combustion takes place via the Mars van Krevelen（MvK） mechanism,and its reaction pathways are as follows:n-hexane→olefins or 3-hexyl hydroperoxide→3-hexanone,2-hexanone or 2,5-dimethyltetrahydrofuran→2-methyloxirane or 2-ethyl-oxetane→acrylic acid→COx→CO2and H2O.

关键词： Three-dimensional ordered mesoporous chromium oxide Supported bimetallic single-atom catalyst Cobalt−nickel single atoms n -Hexane combustion Catalytic reaction mechanism

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Predicting Credit Bond Default with Deep Learning: Evidence from China

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Journal of Social Computing 2024年第1期5卷 36-45页

作者： Ning Zhang Wenhe Li Haoxiang Chen bins.u jia.pei deng School of Information Central University of Finance and EconomicsBeijing 100081China SDIC Taikang Trust Co. Ltd.Beijing 100034China

China’s credit bond market has rapidly expanded in recent ***,since 2014,the number of credit bond defaults has been increasing rapidly,posing enormous potential risks to the stability of the financial *** study proposed a deep learning approach to predict credit bond defaults in the Chinese market.A convolutional neural network(CNN)was selected as the classification model and to reduce the extreme imbalance between defaulted and non-defaulted bonds,and a generative adversarial network(GAN)was used as the oversampling *** on 31 financial and 20 non-financial indicators,we collected Wind data on all credit bonds issued and matured or defaulted from 2014 to *** experimental results showed that our GAN+CNN approach had superior predictive performance with an area under the curve(AuC)of 0.9157 and precision of 0.8871 compared to previous research and other commonly used classification models-including the logistic regression,support vector machine,and fully connected neural network models-and oversampling techniques-including the synthetic minority oversampling technique(SMOTE)and Borderline SMOTE *** one-year predictions,indicators of solvency,capital structure,and fundamental properties of bonds are proved to be the most important indicators.

关键词： credit bond default prediction convolutional neural network imbalanced data processing generative adversarial network

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Deployment analysis of composite thin-walled lenticular tubes with effect of storage time and temperature

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Chinese Journal of Aeronautics 2024年第1期37卷 162-172页

作者： Jinfeng deng Ning AN Qilong jia Xiaofei MA School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China State Key Laboratory for Strength and Vibration of Mechanical Structures School of AerospaceXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Xi’an Institute of Space Radio Technology Xi’an 710100China

Composite Thin-walled Lenticular Tube(CTLT)is increasingly utilized in small satellites missions as a lightweight,foldable,and rollable structural material that facilitates the construction of large deployable *** CTLT is initially flattened and coiled around a central hub for storage before launch,during which elastic energy is stored as deformation energy,allowing it to be self-deployed on demand for use in *** work presents a comprehensive investigation into the coiling,storage and deployment behaviors of CTLT that wraps around a central hub.A nonlinear explicit dynamic finite element model was developed with both deformable CTLT and rigidbodies mechanisms including the central hub and guide rollers,as well as the complex interactions among *** coiling mechanics characteristics such as stored strain energy and rotational moment were presented and validated against experimental data in the ***,the dynamic deployment behaviors were analyzed in terms of two different deployment methods,namely,controlled deployment and free *** effect of material property change during storage was also discussed through numerical experiments.

关键词： Composite deployable structures Deployment dynamics Finite element method Stress relaxation Thin-walled booms

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Large isolated fibrous tumors in the upper esophagus: A case report

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 543-549页

作者： jia-jia Yu Huan-Shuang pei Yu Meng Department of Anesthesiology The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROuND Solitary fibrous tumors(SFT)are rare spindle cell tumors that are usually benign.A total of 10 cases of SFTs in the upper esophagus have ever been ***,we report the anesthetic management of a patient with a large isolated fibrous tumor of the upper esophagus compressing the tracheal *** also provide a literature review of the current *** SuMMARY We report the case of a 49 year old male with“cough aggravation and wheezing after exercise”,who underwent esophagectomy for a large isolated fibrous tumor compressing the tracheal membrane in the upper *** advise the use of a single-lumen tube with a blocker in patients with difficult airways to reduce the incidence of airway injury and fibrinoscopy at all stages of the perioperative period to guide airway *** case study is the first report of the anesthetic management of a large,isolated fibrous tumor compressing the tracheal membrane in the upper *** This rare case emphasizes the importance of perioperative management of anesthesia in patients with large isolated fibrous tumors of the upper esophagus that compress the tracheal *** use of blocker reduce the incidence of airway injury and fibrinoscopy at the perioperative period to guide airway mana-gement.

关键词： upper esophagus Isolated fibrous tumor Tracheal membrane Peak airway pressure Case report

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The Perturbed Compound Poisson Risk Model with Proportional Investment

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 109-128页

作者： Nai-dan deng Chun-wei Wang jia-en Xu School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang471023China

In this paper, the insurance company considers venture capital and risk-free investment in a constant proportion. The surplus process is perturbed by diffusion. At first, the integro-differential equations satisfied by the expected discounted dividend payments and the Gerber-Shiu function are derived. Then, the approximate solutions of the integro-differential equations are obtained through the sinc method. Finally, the numerical examples are given when the claim sizes follow different distributions. Furthermore, the errors between the explicit solution and the numerical solution are discussed in a special case.

关键词： expected discounted dividend payments lognormal distribution proportional investment perturbed risk model sinc numerical method

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Electrochemical Oxygen Evolution Performance of Nitrogen-Doped ultra-Thin Carbon Nanosheets Composite Ru1Co Single Atom Alloy Catalysts

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Chinese Journal of Chemistry 2024年第9期42卷 973-979页

作者： Ziwei deng Zhiyi Sun Yaqiong Li jiajing pei Wenxing Chen Energy&Catalysis Center Schoolof Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 00049China

Energy transformation is imminent,and hydrogen energy is one of the important new energy *** of the keys to increasing the rate of hydrogen evolution during electrolysis is the use of high-performance catalysts for oxygen evolution reactions(OER).Single-atom alloys(SAAs)have garnered significant attention because they partially reduce costs and combine the advantages of both single-atom catalysts(SACs)and alloy ***,an efficient pyrolysis strategy based on a mixing and drying process is designed to anchor ultra-small Co cluster particles,combined with Ru single atoms dispersed on nitrogen-doped ultra-thin carbon nanosheets(Ru_(1)Co SAA/NC).The prepared electrocatalyst exhibits superior OER activity and superb stability,demonstrating an overpotential of 238 mV for OER with a current density of 10 mA·cm^(-2) in 0.5 mol/L H_(2)SO_(4).And we also utilized in-situ XAS to detect the oxidation state of Ru sites during *** in all,this method achieves cost reductions and efficiency improvements through the design of SAAs,offering new prospects for the structural transformation of clean energy.

关键词： Oxygen evolution reaction Single alloy catalyst ultra-thin carbon nanosheets Electrocatalyst Pyrolysis RuiCo SAA/NC

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Implementation of integrated nonlocal sensing for object shape and rotational speed

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 6-12页

作者： Zhenyu Guo Yunlong Wang Zehong Chang jiawei Wang Junliang jia.pei Zhang Ministry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Quantum Information and Quantum Optoelectronic DevicesSchool of PhysicsXi’an Jiaotong UniversityXi’an 710049China

The expeditious acquisition of information pertaining to objects through the utilization of quantum technology has been a perennial issue of *** far,the efficient utilization of information from dynamic objects with limited resources remains a significant ***,we realize a nonlocal integrated sensing of the object's amplitude and phase information by combining digital spiral imaging with the correlated orbital angular momentum *** amplitude information is utilized for object identification,while the phase information enables us to determine the rotational *** demonstrate the nonlocal identification of a rotating object's shape,irrespective of its rotational symmetry,and introduce the concept of the correlated rotational Doppler effect,establishing a fundamental connection between this effect and the classical rotational Doppler effect,i.e.,that both rely on extracting crucial information from the spiral spectrum of *** present study highlights a promising pathway towards the realization of quantum remote sensing and imaging.

关键词： digital spiral imaging orbital angular momentum correlated rotational Doppler effect

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Single-cell RNA sequencing to understand host-virus interactions

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Virologica Sinica 2024年第1期39卷 1-8页

作者： jia-Tong Chang Li-Bo Liu pei-Gang Wang Jing An Department of Microbiology School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China

Single-cell RNA sequencing(scRNA-seq)has allowed for the profiling of host and virus transcripts and host-virus interactions at single-cell *** review summarizes the existing scRNA-seq technologies together with their strengths and *** applications of scRNA-seq in various virological studies are discussed in depth,which broaden the understanding of the immune atlas,host-virus interactions,and immune ***-seq can be widely used for virology in the near future to better understand the pathogenic mechanisms and discover more effective therapeutic strategies.

关键词： Single-cell RNA sequencing(scRNA-seq) Host-virus interaction COVID-19 Flavivirus

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Effects of combustion temperature on the optical properties of brown carbon from biomass burning

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Journal of Environmental Sciences 2024年第3期137卷 302-309页

作者： Peng Gao Rule deng Song jia Yue Li Xuefei Wang Qian Xing School of Chemistry Sciences University of Chinese Academy of SciencesBeijing 100049China College of Chemistry and Materials Engineering Beijing Technology and Business UniversityBeijing 100048China

Biomass burning has been known as one of main sources of Brown Carbon(BrC)in *** this study,by controlling the combustion temperature at 250℃,350℃,and 450℃,the methanol soluble organic carbon(MSOC)and methanol insoluble carbon(MISC)from pine wood burning was collected by ***–Vis,excitation emission matrix(EEM),TEM and FTIR spectra were applied to investigate the properties of BrC *** MSOC at 250℃ and 350℃,all the spectral profiles of uV–Vis absorption and excitation emission matrix are almost the same,while the EEM of MSOC at 450℃ are different from that of the other *** MISC fuorescence was observed only in the case of 450℃.In the FTIR spectra,with the temperature increasing the peaks associated to the oxygen-contained functions was weakened,indicating the formation of the fuorophores with larger conjugated system,especially aromatic *** results show that biomass combustion at low temperature produces more oxygen-riched BrC,which possesses relatively lower light absorption,while at high temperature produces more aromatics hydrocarbons with relatively strong light *** results of this work are helpful to trace the source of brown carbon and optimize biomass energy utilization.

关键词： Biomass burning Combustion temperature Methanol-soluble brown carbon EEM Impinger

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Slow magnetic relaxation and photoluminescence behaviors of dilanthanide complexes bearing N_(8)O_(2)donor macrocyclic ligand

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Journal of Rare Earths 2024年第7期42卷 1298-1303,I0004页

作者： pei-Yu Liao Yu-Quan Qi Zhen Li jian-Hua jia Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou510006China

On account of the complicated magnetic exchange interactions between lanthanide ions,binuclear lanthanide complexes have broad application prospect in the field of single-molecule ***,it is necessary to develop reasonable bridging ligands to manipulate the directional assembly of binuclear lanthanide ***,we selected the macrocyclic ligand L^(N_(8)O_(2))to build up two new dilanthanide complexes[Ln_(2)(LN_(8)O_(2))(OpyO)_(2)(H_(2)O)2](NO_(3))_(2)(1-Ln,Ln=Dy,Tb;LN_(8)O_(2)=hexamethyl-tetraaza-dioxe-dipyrazolacycloicosaphane-2,9,12,19-tetraene;OpyOH=2-pyridinol-1-oxide).Dynamic magnetic studies show that 1-Dy exhibits slow relaxation behavior under a 1 kOe applied *** fitting analysis of relaxation times gives the effective energy barrier of 38.2 cm^(−1),and reveals that the slow magnetic relaxation behavior is dominated by the Orbach and Raman ***-resolution luminescence emission spectrum indicates the energy gap of 36.8 cm^(−1)between the ground state and the first excited state,consistent with the magnetic measurement results.1-Tb exhibits brilliant characteristic green light emission under uV light *** absolute quantum yield of 1-Tb is 44.8%,and its first-order fitted decay lifetime is 779.21μs at room *** study provides the way for directional construction of high-performance molecular materials with magnetic and optical dual-function.

关键词： Dilanthanide complexes Single-molecule magnets Macrocyclic ligand Photoluminescence behavior Rare earths

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