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Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song he li li Sai Wang Shao-jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of fundamental Physics and mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(foPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this foPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Preparation of Co/S co-doped carbon catalysts for excellent methylene blue degradation

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International Journal of minerals,metallurgy and materials 2025年第1期32卷 169-181页

作者： haixu li haobo he Tiannan jiang yunfei Du Zhichen Wu liang xu xinjie Wang xiaoguang liu Wanhua yu Wendong xue School of materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Beijing Jinyu Tongda Refractory Technologies Co. Ltd.Beijing 100085China

S and Co co-doped carbon catalysts were prepared via pyrolysis of mOf-71 and thiourea mixtures at 800℃at a mass ratio of mOf-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PmS)for methylene blue(mB)*** effects of two different mixing routes were identified on the mB degradation ***,the catalyst obtained by the alcohol solvent evaporation(mOf-AEP)mixing route could degrade 95.60%mB(50 mg/l)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(mOf-DGP,80.97%,K=0.39 min^(-1)).x-ray photoelectron spectroscopy revealed that the Co-S content of mOf-AEP(43.39at%)was less than that of mOf-DGP(54.73at%),and the proportion of C-S-C in mOf-AEP(13.56at%)was higher than that of mOf-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PmS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PmS compared with ***,the degradation parameters,including ph and mOf-AEP dosage,were ***,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading mB.

关键词： advanced oxidation process alcohol solvent evaporation hydrogen bond S and Co co-doped carbon catalysts wastewater remediation

Deep learning-based software engineering: progress,challenges, and opportunities

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Science China(Information Sciences) 2025年第1期68卷 57-144页

作者： xiangping CheN xing hU yuan hUANG he jiang Weixing JI yanjie jiang yanyan jiang Bo liu hui liu xiaochen lI xiaoli lIAN Guozhu mENG xin PENG hailong SUN lin ShI Bo WANG Chong WANG Jiayi WANG Tiantian WANG Jifeng xUAN xin xIA yibiao yANG yixin yANG li ZhANG yuming ZhOU lu ZhANG School of Journalism and Communication Sun Yat-sen University School of Software Technology Zhejiang University School of Software Engineering Sun Yat-sen University School of Software Dalian University of Technology School of Computer Science and Technology Beijing Institute of Technology Key laboratory of high Confidence Software Technologies (Peking University) Ministry of EducationSchool of Computer Science Peking University State Key laboratory for Novel Software Technology Nanjing University School of Computer Science and Engineering Beihang University Institute of Information Engineering Chinese Academy of Sciences School of Computer Science Fudan University State Key laboratory of Complex & Critical Software Environment (CCSE) School of Software Beihang University School of Computer and Information Technology Beijing Jiaotong University School of Computer Science and Technology Harbin Institute of Technology School of Computer Science Wuhan University huawei Technologies

Researchers have recently achieved significant advances in deep learning techniques, which in turn has substantially advanced other research disciplines, such as natural language processing, image processing, speech recognition, and software engineering. Various deep learning techniques have been successfully employed to facilitate software engineering tasks, including code generation, software refactoring, and fault localization. many studies have also been presented in top conferences and journals, demonstrating the applications of deep learning techniques in resolving various software engineering tasks. however,although several surveys have provided overall pictures of the application of deep learning techniques in software engineering,they focus more on learning techniques, that is, what kind of deep learning techniques are employed and how deep models are trained or fine-tuned for software engineering tasks. We still lack surveys explaining the advances of subareas in software engineering driven by deep learning techniques, as well as challenges and opportunities in each subarea. To this end, in this study, we present the first task-oriented survey on deep learning-based software engineering. It covers twelve major software engineering subareas significantly impacted by deep learning techniques. Such subareas spread out through the whole lifecycle of software development and maintenance, including requirements engineering, software development, testing, maintenance, and developer collaboration. As we believe that deep learning may provide an opportunity to revolutionize the whole discipline of software engineering, providing one survey covering as many subareas as possible in software engineering can help future research push forward the frontier of deep learning-based software engineering more systematically. for each of the selected subareas,we highlight the major advances achieved by applying deep learning techniques with pointers to the available datasets i

关键词： deep learning software engineering software benchmark software artifact representation survey

hard yet tough and self-lubricating(CuNiTiNbCr)C_(x) high-entropy nanocomposite films:Effects of carbon content on structure and properties

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Journal of materials Science & Technology 2024年第6期173卷 20-30页

作者： y.T.li x.m.Chen x.K.Zeng m.liu x.jiang y.x.leng Key laboratory of Advanced Technologies of materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Key laboratory of Noise and Vibration Research Institute of AcousticsChinese Academy of SciencesBeijing 100190China State Key laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China School of mechanical and Electrical Engineering Mianyang Teachers’CollegeMianyang 621000China

The single-phase high-entropy alloy film is difficult to meet severe friction conditions due to its low hardness and high friction ***-composite structure film is composed of at least two separated phases,showing the properties of strength and toughness integration and excellent wear *** design of nanocomposite structures can effectively improve the mechanical properties and tribological properties of high-entropy alloy *** this study,the(CuNiTiNbCr)C_(x) nanocomposite high-entropy films(hefs)integrated with high hardness,high toughness,and self-lubrication were synthesized by the double-target co-sputtering *** effect of carbon content on microstructure,mechanical properties,and tribological properties of(CuNiTiNbCr)C_(x) films was *** the increase of carbon content in the hefs,the carbon atoms preferentially react with Ti,Nb,and Cr to form a(TiNbCr)C ceramic-reinforced phase,and then the excess carbon atoms precipitate in the form of amorphous carbon(a-C)lubricating phase in the *** structure of the hefs changes from an amorphous structure to a nanocomposite structure of amorphous(amorphous CuNiTiNbCr phase+a-C phase)/nanocrystalline(TiN-bCr)C *** the carbon content is about 21.2 at.%,the carbide phase in the film reaches saturation and the hardness and modulus of the films are highest,which are 18 GPa and 228 GPa,*** hefs with a carbon content of 44.0 at.%show the best toughness and tribological properties with a friction coefficient of 0.16 and a wear rate of 2.4×10^(-6) mm^(3)/(N m),which is mainly attributed to the excellent resistance to fatigue crack growth and the interfacial lubricating layer formed in the friction *** nanocomposite(CuNiTiNbCr)C_(x) hefs show very promising application prospect in the field of friction protection.

关键词： high-entropy films Nanocomposite double-target co-sputtering Strengthening-toughening Tribological properties

On Temperature and Strain Rate Dependent Strain localization Behavior in Ti-6.5Al-3.5mo-1.5Zr-0.3Si Alloy

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Journal of materials Science & Technology 2013年第3期29卷 273-278页

作者： B.Zhang l.m.lei x.l.jiang Z.m.Song x.huang G.P.Zhang Key laboratory for Anisotropy and Texture of materials(ministry of Education) Northeastern University Titanium Alloys laboratory Beijing Institute of Aeronautical Materials AVIC commercial Aircraft Engine Co. Ltd. Shenyang National laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences

Deformation behaviors of Ti-6.5Al-3.5mo-1.5Zr-0.3Si alloys with α/β lamellar structure were investigated systematically at different temperatures from room temperature to 950 ~C and different strain rates. Results reveal that when the deformation temperature is higher than a critical temperature of 600℃, an evident transition of deformation behavior from localized shear banding to α/β lamella kinking, flow softening and temperature/strain rate-dependent peak flow stress occurred in the alloy. The critical conditions for the occurrence of internal cracking and strain localization behavior associated with temperature and strain rate were determined.

关键词： Titanium alloy hot working Temperature Strain rate Shear band

Enhanced mechanical performance of grain boundary precipitation-hardened high-entropy alloys via a phase transformation at grain boundaries

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Journal of materials Science & Technology 2021年第27期86卷 271-284页

作者： y.l.Qi l.Zhao x.Sun h.x.Zong x.D.Ding f.jiang h.l.Zhang y.K.Wu l.he f.liu S.B.Jin G.Sha J.Sun State Key laboratory for mechanical Behavior of materials Xi’an Jiaotong UniversityXi’an710049China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an710072China School of materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China

Grain-boundary(GB)precipitation has a significant adverse effect on plasticity of alloys,which easily leads to catastrophic intergranular failure in safety-critical applications under high external ***,we report a novel strategy that uses the local stress concentration induced by GB precipitates as a driving force to trigger phase transformation of preset non-equiatomic high-entropy solid-solution phase at *** in situ deformation-induced phase transformation at GBs introduces a well-known effect:transformation-induced plasticity(TRIP),which enables an exceptional elongation to fracture(above 38%)at a high strength(above 1.5 GPa)in a GB precipitation-hardened high-entropy alloy(heA).The present strategy in terms of"local stress concentration-induced phase transformations at GBs"may provide a fundamental approach by taking advantage of(rather than avoiding)the GB precipitation to gain a superior combination of high strength and high ductility in heAs.

关键词： Non-equiatomic Grain-boundary precipitation high-entropy alloys Ductility Transformation-induced plasticity

Synthesis of morphology-controlled silver nanostructures by electrodeposition

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Nano-micro letters 2010年第1期2卷 6-10页

作者： C.l.liang K.Zhong m.liu l.jiang S.K.liu D.D.xing h.y.li y.Na W.x.Zhao y.x.Tong P.liu Instrumental Analysis & Research Center Sun Yat-sen University School of Chemistry and Chemical Engineering Sun Yat-sen University

Nanostructured silver was obtained by potentiostatic *** effects of ionized surfactant(sodium dodecanesulphonate)and the substrate(Cu and Ti)on the morphology of depositions were *** is found that morphologies of silver nanostructures can be simply controlled via change of the *** Ag nanoparticles with narrow size distribution were obtained by electrodeposition in Ag NO3-SDS aqueous solution on copper *** the case of titanium substrate,silver dendrite structures were *** of different morphologies,xRD and TEm results showed that the as-prepared samples belong to face-centered cubic silver structure with good *** formation mechanism of different silver nanostructures was discussed.

关键词： Electrodeposition Silver nanopartilces Silver nano dentrites

Beginning from the end:the presynaptic terminal as a pathomechanism hub in frontotemporal dementia and amyotrophic lateral sclerosis

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Neural Regeneration Research 2025年第11期20卷 3217-3218页

作者： laura huggon Emma l.Clayton UK Dementia Research Institute at King’s College london LondonUK Department of Basic and Clinical Neuroscience Institute of Psychiatry Psychology&NeuroscienceKing’s College LondonLondonUK

frontotemporal dementia and amyotrophic lateral sclerosis:frontotemporal dementia(f T D)and amyo t rophic lateral sclerosis(AlS)are neurodegenerative diseases with significant overlapping *** these neurodegenerative diseases affect different neuronal populations(with fTD affecting neurons of the frontal and temporal lobes,and AlS affecting upper and lower motor neurons),these two diseases are complexly *** and AlS exist on a disease spectrum,with shared genetic causes,clinical presentations,and pathologies.

关键词： diseases amyotrophic sclerosis

The Quantum Dots Characteristics of hydrogenated Nanocrystalline Silicon films

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The Quantum Dots Characteristics of Hydrogenated Nanocrystal...