检索结果-南通市图书馆

Triple reverse order law for the Drazin inverse

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： WANG Hua zhong cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation relations.Moreover,the Drazin invertibility of sum is also obtained for two bounded linea... 详细信息

关键词： Drazin inverse reverse order law space decomposition

Two-dimensional layered In_(2)P_(3)S_(9): A novel superior anode material for sodium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第3期90卷 294-304,I0008页

作者： Longsheng zhong Hongneng chen Yanzhe Sheng Yiting Sun Yanhe Xiao Baochang cheng Shuijin Lei School of Physics and Materials Science Nanchang UniversityNanchang 330031JiangxiChina

Developing reliable and efficient anode materials is essential for the successfully practical application of sodium-ion batteries.Herein,employing a straightforward and rapid chemical vapor deposition technique,two-dimensional layered ternary indium phosphorus sulfide(In_(2)P_(3)S_(9)) nanosheets are prepared.The layered structure and ternary composition of the In_(2)P_(3)S_(9) electrode result in impressive electrochemical performance,including a high reversible capacity of 704 mA h g^(-1) at 0.1 A g^(-1),an outstanding rate capability with 425 mA h g^(-1) at 5 A g^(-1),and an exceptional cycling stability with a capacity retention of88% after 350 cycles at 1 A g^(-1).Furthermore,sodium-ion full cell also affords a high capacity of 308 and114 mA h g^(-1) at 0.1 and 5 A g^(-1).Ex-situ X-ray diffraction and ex-situ high-resolution transmission electron microscopy tests are conducted to investigate the underlying Na-storage mechanism of In_(2)P_(3)S_(9).The results reveal that during the first cycle,the P-S bond is broken to form the elemental P and In_(2)S_(3),collectively contributing to a remarkably high reversible specific capacity.The excellent electrochemical energy storage results corroborate the practical application potential of In_(2)P_(3)S_(9) for sodium-ion batteries.

关键词： Metal thiophosphate In_(2)P_(3)S_(9) Anode material Sodium-ion battery Full cell

Mixing states and secondary formation processes of organic nitrogen-containing single particles in Guangzhou,China

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第4期138卷 62-73页

作者： Lijun Yun Chunlei cheng Suxia Yang Zaihua Wang Mei Li Qi En zhong LiyuanMao Sulin Liu Xiaoya cheng Duanying chen Fan Yang Zhen Zhou Institute of Mass Spectrometry and Atmospheric Environment Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollutionJinan UniversityGuangzhou 510632China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 510632China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy ScienceXi’an 710061China Institute for Environment and Climate Research Jinan UniversityGuangzhou 510632China Guangdong Academy of Sciences Institute of Resources Utilization and Rare Earth DevelopmentGuangzhou 510650China Environmental Monitoring Station of Pudong New District Shanghai 201200China

Organic nitrogen(ON)compounds play a significant role in the light absorption of brown carbon and the formation of organic aerosols,however,the mixing state,secondary formation processes,and influencing factors of ON compounds are still unclear.This paper reports on the mixing state of ON-containing particles based on measurements obtained using a highperformance single particle aerosol mass spectrometer in January 2020 in Guangzhou.The ON-containing particles accounted for 21% of the total detected single particles,and the particle count and number fraction of the ON-containing particles were two times higher at night than during the day.The prominent increase in the content of ON-containing particles with the enhancement of NO_xmainly occurred at night,and accompanied by high relative humidity and nitrate,which were associated with heterogeneous reactions between organics and gaseous NO_(x)and/or NO_(3)radical.The synchronous decreases in ON-containing particles and the mass absorption coefficient of water-soluble extracts at 365 nm in the afternoon may be associated with photo-bleaching of the ON species in the particles.In addition,the positive matrix factorization analysis found five factors dominated the formation processes of ON particles,and the nitrate factor(33%)mainly contributed to the production of ON particles at night.The results of this study provide unique insights into the mixing states and secondary formation processes of the ON-containing particles.

关键词： Organic nitrogen compounds Single particles Mixing state Secondary formation Nighttime chemistry

Microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents during heat treatments

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第4期43卷 1786-1792页

作者： Yuan-Feng Xie Xing-cheng Xie zhong-Wu Li Rui-Jun Cao zhong-Kun Lin Qing Li chen-Guang Lin Powder Metallurgy and Special Materials Research Department General Research Institute for Nonferrous Metals

The effects of cryogenic treatment（CT） and tempering-cryogenic treatment（TCT） on the microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents were researched.The binder phase,WC mean grain sizes,W solubility in the binder,relative magnetic s aturation,densities,hardness,wear resistance and second phase precipitation of cemented carbides with different heat treatments were discussed.The results show that there are significant changes of microstructure and properties in the samples with CT and TCT,especially due to the precipitation of metastable nanoparticles WxCoyCzin the binder during the heat treatments of CT and TCT.With the simultaneous combination of microstructure and nanoparticle-reinforced binder,a dramatically improved combination of hardness and wear resistance of the samples after TCT has been achieved.

关键词： Cryogenic treatment Tempering Coarse-grained cemented carbide Carbon content Nanoparticle-reinforced binder

A Possible X-ray Quasi-periodic Oscillation in the Narrow-line Seyfert 1 Galaxy Mrk 142

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第6期24卷 193-202页

作者： Xiao-Gu zhong Jian-cheng Wang Yong-Yun chen Xiao-Ling Yu College of Physics and Electronic Engineering Qujing Normal University Yunnan Observatories Chinese Academy of Sciences

A possible quasi-periodic oscillation（QPO） at frequency 7.045 × 10-5Hz is found in the narrow-line Seyfert 1galaxy Mrk 142 in the data of XMM-Newton collected on 2020 April 11. We find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3–10 keV band by using the method of the Lomb–Scargle Periodogram, the Weighted Wavelet Z-transform and the REDFIT.We analyze the data in 0.3–0.6 keV, 0.6–1 keV, 1–3 keV and 3–10 keV energy bands, and find obvious QPO signals at 0.3–0.6 keV and 1–3 keV bands. We then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10-5Hz, and use a model to fit them. We find that the QPO signal mainly comes from the X-ray hot corona.

关键词： accretion accretion disks galaxies: Seyfert radiation mechanisms: general X-rays: galaxies

Probing the electric double layer structure at nitrogen-doped graphite electrodes by constant-potential molecular dynamics simulations

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第6期93卷 299-305,I0008页

作者： Legeng Yu Nan Yao Yu-chen Gao zhong-Heng Fu Bo Jiang Ruiping Li cheng Tang Xiang chen Tsinghua Center for Green Chemical Engineering Electrification(CCEE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Ordos Carbon Neutral Research and Application Co. Ltd.Ordos 017010Inner Mongoli1China Institute for Carbon Neutrality Tsinghua UniversityBeijing 100084China Center for Next-Generation Energy Materials and School of Chemical Engineering Sungkyunkwan University2066 Seobu-roJangan-guSuwon-siGyeonggi-do 16419Republic of Korea

Electric double layer(EDL)is a critical topic in electrochemistry and largely determines the working performance of lithium batteries.However,atomic insights into the EDL structures on heteroatom-modified graphite anodes and EDL evolution with electrode potential are very lacking.Herein,a constant-potential molecular dynamics(CPMD)method is proposed to probe the EDL structure under working conditions,taking N-doped graphite electrodes and carbonate electrolytes as an example.An interface model was developed,incorporating the electrode potential and atom electronegativities.As a result,an insightful atomic scenario for the EDL structure under varied electrode potentials has been established,which unveils the important role of doping sites in regulating both the EDL structures and the following electrochemical reactions at the atomic level.Specifically,the negatively charged N atoms repel the anions and adsorb Li~+at high and low potentials,respectively.Such preferential adsorption suggests that Ndoped graphite can promote Li~+desolvation and regulate the location of Li~+deposition.This CPMD method not only unveils the mysterious function of N-doping from the viewpoint of EDL at the atomic level but also applies to probe the interfacial structure on other complicated electrodes.

关键词： Lithium batteries Graphite N-doping Electric double layer Molecular dynamics Constant potential method Electrode potential

Market Equilibrium Based on Cloud-edge Collaboration

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2024年第1期10卷 96-104页

作者： Tong cheng Haiwang zhong Qing Xia the State Key Laboratory of Power Systems the Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

Market participants can only bid with lagged information disclosure under the existing market mechanism,which can lead to information asymmetry and irrational market behavior,thus influencing market efficiency.To promote rational bidding behavior of market participants and improve market efficiency,a novel electricity market mechanism based on cloudedge collaboration is proposed in this paper.Critical market information,called residual demand curve,is published to market participants in real-time on the cloud side,while participants on the edge side are allowed to adjust their bids according to the information disclosure prior to closure gate.The proposed mechanism can encourage rational bids in an incentive-compatible way through the process of dynamic equilibrium while protecting participants’privacy.This paper further formulates the mathematical model of market equilibrium to simulate the process of each market participant’s strategic bidding behavior towards equilibrium.A case study based on the IEEE 30-bus system shows the proposed market mechanism can effectively guide bidding behavior of market participants,while condensing exchanged information and protecting privacy of participants.

关键词： Cloud-edge collaboration market mechanism residual demand curve strategic bidding

Recent Advances in Nickel Catalyzed Carbonylative Reactions via the Insertion of Carbon Monoxide

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第2期42卷 177-189页

作者： Xinzhou chen Gang chen zhong Lian Department of Dermatology State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610041China

Carbonyl compounds have attracted considerable attention due to their extensive applications in drug discovery.Furthermore,they are important synthetic intermediates for the construction of carbon-carbon and carbon-heteroatom bonds.Transition-metal-catalyzed carbonylation via the insertion of co is one of the most efficient and straightforward strategies to access carbonyl compounds.However,most of the transition-metal-catalyzed carbonylative reactions require expensive and toxic noble-metal catalysts.Therefore,there is a growing demand for the exploration of nickel-catalyzed carbonylative reactions via the insertion of CO due to the earth abundance and low cost of nickel.Compared with the well-established palladium-catalyzed carbonylative reactions,nickel-catalyzed analogous transformations have been relatively underdeveloped.This is primarily because CO strongly binds to nickel,often resulting in catalyst poisoning.In recent years,some research groups have focused on using CO surrogates or NN_(2) pincer nickel catalyst to circumvent the formation of Ni(CO)_(4).Nickel-catalyzed carbonylation has been applied in the construction of carbonyl-containing compounds,such as ketones,carboxylic acids,thioesters,acyl chloride and carboxamides.

关键词： Carbonylation Nickel catalysis Carbon monoxide C1 chemistry Carbonyl-containing compounds

In vivo label-free measurement of blood flow velocity symmetry based on dual line scanning third-harmonic generation microscopy excited at the 1700 nm window

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Innovative Optical Health Sciences 2024年第1期17卷 61-68页

作者： Hui cheng Jincheng zhong Ping Qiu Ke Wang Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University Shenzhen 518060 P.R.China

Measurement of bloodflow velocity is key to understanding physiology and pathology in vivo.While most measurements are performed at the middle of the blood vessel,little research has been done on characterizing the instantaneous bloodflow velocity distribution.This is mainly due to the lack of measurement technology with high spatial and temporal resolution.Here,we tackle this problem with our recently developed dual-wavelength line-scan third-harmonic generation(THG)imaging technology.Simultaneous acquisition of dual-wavelength THG line-scanning signals enables measurement of bloodflow velocities at two radially symmetric positions in both venules and arterioles in mouse brain in vivo.Our results clearly show that the instantaneous bloodflow velocity is not symmetric under general conditions.

关键词： 1700 nm-Window third-harmonic generation imaging blood flow velocity