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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 525-532页

作者： Z. Zhang c. cai F.H. cao Z.n. Gao J.Q. Zhang c.n. cao Department of chemistry Zhejiang University Hangzhou 310027 China Department of chemistry Ningxia University Yinchuan 750021 China State Key Laboratory for corrosion and Protection of Metals Institute of Metal Research The Chinese

The corrosion behavior of pure aluminum in neutral 3.0% （mass fraction） sodium chloride （na-cl） solution has been studied using electrochemical impedance spectroscopy （EIS） measurement in c.n.unction with the sc.n.ing electron microscopy （SEM） tec.n.que. EIS information on the evolution of pitting corrosion over a period of 15 days has been obtained and analyzed with equivalent circuit tec.n.que. The results shown that, during the ensemble c.n.tant immersion time, two time c.n.tants involved, the high frequency one originated from the protective layer on the corroding surface while the low frequenO, one from the diffusion process or the corrosion reaction and so on. And there existed a period for oxide film to growth and thickening prior to the of the attacking of chloride ions to the substrate. Meanwhile, good relationship between EIS and the material corrosion type/severity has been obtained, which has been interpreted according to the characteristics of corrosion process such as auto acceleration of pitting corrosion and the protection of local anodic reaction to the area around them.

关键词： pure aluminum pitting corrosion electrochemical impedance spectroscopy pit-rnorphology

DEcREASInG PITTInG SUScEPTIBILITY OF PASSIVE FILMS On X70 PIPELInE STEEL In nacl SOLUTIOnS BY ILLUMInATIOn

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 91-97页

作者： W.c. Zhu W.H. Leng J.Q. Zhang c.n. cao Department of chemistry Zhejiang University Hangzhou 310027 China State Key Laboratory for corrosion and Protection of Metals Institute of Metal Research The Chinese Academy of Sciences Shenyang 110016 China

The influence of UV illumination on passivity and pitting susceptibility on X70 pipoeline steel in a borate buffer （pH=8.4 ） solution c.n.aining nacl is described. It is observed that illumination of the sample leads to a decrease in its pitting susceptibility as indicated by pitting potential and incubation time measurements in chloride c.n.aining electrolytes. This effect is strongly dependent on the applied potential during passivation. The electronic properties of the passive films on X70 steel were studied by Mott-Schottky analysis and photocurrent transient measurements. The results indicated that illumination during passivation led to modifications in the electronic properties of the passive films, mainly to a decrease of the bulk doping and an increase in the surface state density. The cause for the decrease in the pitting susceptibility is preliminary explained in terms of such modifications of the passive flm.

关键词： X70 pipeline steel pitting susceptibility illumination passivation

cORROSIOn MOnITORInG OF LY12 In SODIUM cHLORIDE SOLUTIOn WITH ELEcTROcHEMIcAL nOISE TEc.n.QUE

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 91-96页

作者： J.Q. Zhang, Z. Zhang, J.M. Wang, H.B. Shao and c.n. cao (Department of chemistry, Zhejiang University , Hangzhou 310027, china) (State Key Laboratory for corrosion and Protection of Metals, Institute of Metal Research, The chinese Academy of Sciences, She Dept. of chem. Zhejiang Univ. Hangzhou 310027 China

Spontaneous electrochemical noise (En) c.n.be a rich source of information c.n.erning the processes simultaneously occurring on a corroding interface. But the noise signal is often difficult to be analyzed due to the complicated nature of the specific systems being investigated. In this paper, the potential noise fluctuations during the free corrosion of commercial aluminum alloy LY12 in sodium chloride solution was recorded and analyzed with different tec.n.ques. The typical results showed that the fractal dimension (D,n) obtained from spectral power density (SPD) is mainly directly proportional to the intensity of pitting corrosion and to the value of pitting parameter (SE) derived from dimensional analysis, while the fractal dimension (DE) obtained from EIS is mainly related to the uniform corrosion.

关键词： electrochemical noise fractal stochastic analysis dimensionanalysis localized corrosion

Pt nanodendrites with a PtIr alloy surface structure exhibit excellent stability toward acidic hydrogen evolution reaction

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nano Research 2024年第6期17卷 4844-4849页

作者： chang Liu Zongnan Wei Minna cao Rong cao State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of chinese Academy of Sciences Beijing 100049China Fujian Science and Tec.n.logy Innovation Laboratory for Optoelectronic Information of china Fuzhou 350108China

The development of effective and stable electrocatalysts for the hydrogen evolution reaction(HER)in acidic electrolytes is a signific.n. *** this work,homogeneous Pt nanodendrites(Pt nDs)with a PtIr shell were successfully synthesized by a two-step wet chemical *** open three-dimensional(3D)dendritic structure exhibited exceptional electrocatalytic characteristics,exposing as many active sites as ***,by alloying Ir with Pt on the surface,catalytic activity was greatly enhanced while ensuring extremely high *** surface-enriched platinum nanodendritic catalysts(Pt@PtIr nDs)outperformed the c.n.rol samples and the commercial *** acidic HER test,Pt@PtIr nDs had a lower overpotential(22 mV)than Pt nDs(26 mV)and commercial Pt/c(31 mV)at 10 mA/cm^(2),and the activity of Pt@PtIr nDs remained c.n.istent even after undergoing a c.n.inuous durability test for at least 168 h,which was much superior to the performance of commercial Pt/c(10 h)under identical test *** study revealed that the application of 3D Pt dendritic metal alloys may offer a chance for the development of enhanced electrocatalysts in acidic HER.

关键词： Pt nanodendrites iridium high stability hydrogen evolution reaction alloy

An Involution over Dyck Paths Related with Stirling Statistics

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Journal of Mathematical Research with Applications 2024年第4期44卷 437-443页

作者： Peng cao Joanna n.cHEn college of Science Tianjin University of Technology

We c.n.truct an involution over Dyck paths, which implies the distribution of statistics “the number of peak”, “the number of returns” and “the height of the last peak”. As an application, equidistributions of s... 详细信息

关键词： involutions Dyck paths pattern peak returns

Early Phases of Star Formation: Testing chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.c.Martinez S.Paron c.n.cET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

Star-forming processes strongly influence the ISM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the Hcn/Hnc ratio as a thermometer,and the use of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDcs),highmass protostellar objects(HMPOs),hot molecular cores(HMcs) and ultracompact H II *** found that the use of the Hcn/Hnc ratio as a universal thermometer in the ISM should be taken with care because the Hcn optical depth is a big issue that c.n.affect the ***,this tool should be utilized only after a careful analysis of the Hcn spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H could be useful to trace and distinguish regions among IRDcs,HMPOs and *** molecular line widths of these four species increase from the IRDc to the HMc stage,which c.n.be a c.n.equence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only c.n.ribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation ISM:molecules ISM:clouds

Imprints of a gravitational wave through the weak field deflection of photons

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chinese Physics c 2024年第8期48卷 240-245页

作者： Reggie c.Pantig Ali Övgün Physics Department Mapúa University658 Muralla St.IntramurosManila 1002Philippines Physics Department Eastern Mediterranean UniversityFamagusta99628 North Cyprusvia Mersin 10Turkiye

In this study,we investigate the novel phenomenon of gravitational lensing experienced by gravitational waves traveling past a Schwarzschild black hole perturbed by a specific,first-order,polar gravitational *** apply the Gauss-Bonnet theorem,finding a topological c.n.ribution to the deflection of light rays passing near the black *** demonstrate that the deflection angle c.n.be determined by analyzing a region entirely outside the path of the light ray,leading to a calculation based solely on the parameters of the perturbing wave(Legendre polynomial order,l;frequency,σ).This approach offers a unique perspective on gravitational lensing and expands our understanding of black hole interactions with gravitational waves.

关键词： supermassive black holes gravitational waves chaos weak deflection angle Gauss-Bonnet theorem

Adsorption limitation investigation on olefins for cu–BTc

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Friction 2024年第4期12卷 606-617页

作者： Xiao YAnG Yunbo WAnG Weihua cao Ruizheng JIAnG Guoxin XIE Yuying cao Xiaowen QI School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Key Laboratory of Self-Lubricating Spherical Plain Bearing Tec.n.logy of Hebei Province Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Aviation Key Laboratory of Science and Tec.n.logy on Generic Tec.n.logy of Self-Lubricating Spherical Plain Bearing Yanshan UniversityQinhuangdao 066004China

To utilize cu-benzene-1,3,5-tricarboxylate(cu-BTc)adsorbed lubric.n. oils in the self-lubricating field,the adsorption properties of cu-BTc on different 1-olefins must be *** this work,1-hexene,1-octene,1-nonene,1-dec.n.,1-undec.n.,and 1-dodec.n. were studied by the Monte carlo method and *** adsorption limit of cu-BTc for n-olefins was determined as 1-undec.n. by the adsorption *** suggested a limit for even straight-chain molecules to the adsorption of *** maximum ratio of the olefin length of the largest pore diameter(L/D)of cu-BTc was approximately ***,theoretical calculations(radial distribution function(RDF))and experiments(infrared(IR)spectra)c.n.irmed the interaction of n-olefin adsorbates and the cu-BTc framework occurred between the-cH=of olefins and the cu and O atoms of the cu-BTc *** work adds to the understanding and investigation of the adsorption of liquid lubric.n.s using cu-BTc as a metal-organic framework(MOF).

关键词： metal-organic framework(MOF) cu-benzene-1,3,5-tricarboxylate(cu-BTc) Monte carlo method adsorption properties 1-olefins

Sub-10-nm-sized Au@AuxIr1-x metal-core/alloy-shell nanoparticles as highly durable catalysts for acidic water splitting

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national Science Review 2024年第4期11卷 130-140页

作者： Huimin Wang Zhe-ning chen Yuanyuan Wang Dongshuang Wu Minna cao Fanfei Sun Rong cao State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of chinese Academy of Sciences School of Materials Science and Engineering Nanyang Technological University Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics Chinese Academy of Sciences Fujian Science & Tec.n.logy Innovation Laboratory for Optoelectronic Information of china

The absence of efficient and durable catalysts for oxygen evolution reaction（OER） is the main obstacle to hydrogen production through water splitting in an acidic ele ***,we report a c.n.rollable synthesis method of surface IrOxwith changing Au/Ir compositions by c.n.tructing a range of sub-10-nm-sized core-shell nanocatalysts composed of an Au core and AuxIr1-xalloy *** particular,Au@Au0.43Ir0.57exhibits 4.5 times higher intrinsic OER activity than that of the commercial Ir/*** X-ray-based spectroscopies,electron microscopy and density functional theory calculations revealed a balanced binding of reaction intermediates with enhanced *** water-splitting cell using a load of 0.02 mgIr/cm2of Au@Au0.43Ir0.57as both anode and cathode c.n.reach 10 mA/cm2at 1.52 V and maintain activity for at least194 h,which is better than the cell using the commercial couple Ir/c‖Pt/c（1.63 V,0.2 h）.

关键词： c.n.rollable synthesis of surface IrOx oxygen evolution reaction acidic water splitting catalytic stability transition metal catalysts

A Support Data-Based core-Set Selection Method for Signal Recognition

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china communications 2024年第4期21卷 151-162页

作者： Yang Ying Zhu Lidong cao changjie national Key Laboratory of Wireless communications(University of Electronic Science and Tec.n.logy of china) Chengdu 611731China college of computer Science and cyber Security(chengdu University of Tec.n.logy) Chengdu 610059China college of Mathmatics and Physics(chengdu University of Tec.n.logy) Chengdu 610059China

In rec.n. years,deep learning-based signal recognition tec.n.logy has gained attention and emerged as an important approach for safeguarding the electromagnetic ***,training deep learning-based classifiers on large signal datasets with redundant samples requires signific.n. memory and high *** paper proposes a support databased core-set selection method(SD)for signal recognition,aiming to screen a representative subset that approximates the large signal ***,this subset c.n.be identified by employing the labeled information during the early stages of model training,as some training samples are labeled as supporting data *** support data is crucial for model training and c.n.be found using a border sample *** results demonstrate that the SD method minimizes the impact on model recognition performance while reduc.n. the dataset size,and outperforms five other state-of-the-art core-set selection methods when the fraction of training sample kept is less than or equal to 0.3 on the RML2016.04c dataset or 0.5 on the RML22 *** SD method is particularly helpful for signal recognition tasks with limited memory and computing resources.

关键词： core-set selection deep learning model training signal recognition support data