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Chinese Physics letters 2017年第6期 26-36页

作者： X.-X.Yuan l.he S.-T.Wang D.-l.Deng F.Wang W.-Q.lian X.Wang C.-h.zhang h-l.zhang X.-Y.Chang l.-M.Duan Center for Quantum Information Institute for Interdisciplinary Information SciencesTsinghua University Department of Physics University of Michigan Condensed Matter Theory Center and Joint Quantum Institute Department of PhysicsUniversity of Maryland

MATERIAlS AND METhODS Experimental setup We illuminate the diamond Nitrogen-Vacancy(NV)center and collect its fluorescence with a home-built confocal microscope with a 1.49 NA objective(Olympus 60X,under oil immersion... 详细信息

关键词： Supplementary Materials:Observation of topological links associated with hopf insulators in a solid-state quantum simulator

Advances of ferrous and ferric Mossbauer recoilless fractions in minerals and glasses

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Geoscience Frontiers 2022年第2期13卷 78-89页

作者： hongluo l.zhang State Key laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China

Mössbauer spectroscopy has been used widely to characterize the ferric(Fe^(3+))and ferrous(Fe^(2+))proportions and coordination of solid *** obtain these accurately,the recoilless fraction is *** recoilless fractions(f)of iron-bearing minerals,including oxides,oxyhydroxides,silicates,carbonates,phosphates and dichalcogenides,and silicate glasses were evaluated from the temperature dependence of their center shifts or absorption area with the Debye model ***,the resolved Debye temperature(θ_(D))of ferric iron in minerals,except dichalcogenides,through their center shifts ranging from 400 to 550 K,is significantly larger than ferrous iron ranging from 300 to 400 K,which is consistent with the conclusion from previous *** resolved f(Fe^(3+))RT with the center shift model(CSM)ranges from 0.825 to 0.925,which is larger than that obtained for f(Fe^(2+))RT,which ranges from 0.675 to ***,the θ_(D) and f resolved from temperature-dependence of absorption are generally lower than from center shifts,especially for ferric *** significant difference between f(Fe^(3+))and f(Fe^(2+))indicates the necessity of recoilless fraction correction on the Fe^(3+)/(Fe^(3+)+Fe^(2+))resolved from Mössbauer spectra.

关键词： Mossbauer spectroscopy Recoilless fraction Debye temperature Oxidation states Iron ratio

A stabilized complementarity formulation for nonlinear analysis of 3D bimodular materials

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Acta Mechanica Sinica 2016年第3期32卷 481-490页

作者： l.zhang h.W.zhang J.Wu B.Yan Department of Engineering Mechanics College of AerospaceEngineering Chongqing University State Key laboratory of Structural Analysis for IndustrialEquipment Dalian University of Technology

Bi-modulus materials with different mechanical responses in tension and compression are often found in civil,composite, and biological engineering. Numerical analysis of bimodular materials is strongly nonlinear and convergence is usually a problem for traditional iterative schemes. This paper aims to develop a stabilized computational method for nonlinear analysis of 3D bimodular materials. Based on the parametric variational principle, a unified constitutive equation of 3D bimodular materials is proposed, which allows the eight principal stress states to be indicated by three parametric variables introduced in the principal stress *** original problem is transformed into a standard linear complementarity problem（lCP） by the parametric virtual work principle and a quadratic programming algorithm is developed by solving the lCP with the classic lemke＇s algorithm. Update of elasticity and stiffness matrices is avoided and, thus, the proposed algorithm shows an excellent convergence behavior compared with traditional iterative *** examples show that the proposed method is valid and can accurately analyze mechanical responses of 3D bimodular materials. Also, stability of the algorithm is greatly improved.

关键词： Bimodular materials Non-smooth stressstrain relationship Parametric variational principle Complementarity

DISCOVERY OF lATENT STRUCTURES: EXPERIENCE WITh ThE COIl ChAllENGE 2000 DATA SET

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Journal of Systems Science & Complexity 2008年第2期21卷 172-183页

作者： Nevin l.zhang Department of Computer Science and Engineering The Hong Kong University of Science and Technology

The authors present a case study to demonstrate the possibility of discovering complex and interesting latent structures using hierarchical latent class （hlC） models. A similar effort was made earlier by zhang （2002）, but that study involved only small applications with 4 or 5 observed variables and no more than 2 latent variables due to the lack of efficient learning algorithms. Significant progress has been made since then on algorithmic research, and it is now possible to learn hlC models with dozens of observed variables. This allows us to demonstrate the benefits of hlC models more convincingly than before. The authors have successfully analyzed the CoIl Challenge 2000 data set using hlC models. The model obtained consists of 22 latent variables, and its structure is intuitively appealing. It is exciting to know that such a large and meaningful latent structure can be automatically inferred from data.

关键词： Bayesian networks case study latent structure discovery learning.

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong hou Shuo zhang Jie Dang Jia Guo hanghang Zhou Xuewei lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Force and impulse multi-sensor based on flexible gate dielectric field effect transistor

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 214-220页

作者： Chao Tan Junling lü Chunchi zhang Dong liang lei Yang Zegao Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other ***-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate ***,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of *** we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor *** systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 *** sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on ***,there was almost no performance loss for the device as left in the air for two months.

关键词： flexible gate dielectric transistor force sensor impulse sensor force sensor array

TRANSMISSION ElECTRON MICROSCOPY INVESTIGATIONS OF lOW-PRESSURE CVD GROWTh AND STRAIN RElAXATION OF Ge ISlANDS ON Si(110)

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Acta Metallurgica Sinica(English letters) 2005年第3期18卷 427-432页

作者： E.Spiecker l.zhang h.M.lu W.Jaeger l.Vescan MicroanalysisofMaterials FacultyofEngineeringChrisfian-Albrechts-UniversityKielKaiserstraβe224143KielGermany InstituteofThinFilmsandInterfaces ResearchCenterJiilichGmbH52425JiilichGermany

Shapes, dimensions, arrangements and the microstructure of self-assembled island s fabricated by low-pressure chemical vapour deposition (lPCVD) of Ge at 700℃ o nto Si(110) substrates have been investigated for different nominal Ge coverage by transmission electron microscopy (TEM) of plan-view and cross-section specime ns and have been compared with photoluminescence (Pl) measurements of Si-capped layer samples. The transition from the 2-dimensional layer to the 3-dimensional island growth mode takes place for a Ge deposition of nominally less than 2 mono layers. Upon this transition, many coherent islands and few larger islands with extended defects are observed. The coherent islands possess a dome-like shape an d lateral sizes up to 130nm. Photoluminescence spectra show island-related peaks whose energy positions are shifted towards lower energy with higher Ge coverage .

关键词： Si-Ge heteroepitaxy surface transmission electron microscopy Nanostructure

Distribution of tetraether lipids in surface sediments of the northern South China Sea:Implications for TEX_(86) proxies

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Geoscience Frontiers 2013年第2期4卷 223-229页

作者： huangmin Ge Chuanlun l.zhang hongyue Dang Chun Zhu Guodong Jia State Key laboratory of Marine Geology Tongji University Department of Marine Sciences University of Georgia State Key laboratory of heavy Oil Processing & Centre for Bioengineering and Biotechnology China University of Petroleum(East China) MARUM Center for Marine Environmental Sciences and Department of Geosciences University of Bremen CAS Key laboratory of Marginal Sea Geology Guangzhou Institute of GeochemistryChinese Academy of Sciences

Archaea have unique glycerol dialkyl glycerol tetraether（GDGT） lipids that can be used to develop paleotemperature proxies such as *** research is to validate proposed GDGT-proxies for paleotemperature determination in the South China Sea（SCS）.Samples were collected from core-top sediments （0-5 cm） in the northern *** lipids were extracted to obtain core GDGTs,which were identified and quantified using liquid chromatography-mass spectrometry（lC-MS）.The abundance of isoprenoidal GDGTs（/GDGTs） ranged from 271.5 ng/g dry sediment to 1266.3 ng/g dry sediment,whereas the branched GDGTs（bGDGTs）,supposedly derived from terrestrial sources,ranged from 22.2 ng/g dry sediment to 56.7 ng/g dry *** TEX_（86）-derived sea surface temperatures ranged from 20.9℃in the coast（water depth 〈 160 m） to 27.9℃offshore（water depth 〉 1000 m）.TEX86-derived temperatures near shore（〈 160 m water depth） averaged 23.1±2.5℃（n =4）,which were close to the satellite-derived winter mean sea surface temperature（average 22.6±1.0℃,n = 4）;whereas the TEX_（86）-derived temperatures offshore averaged 27.4±0.3℃（n = 7） and were consistent with the satellite mean annual sea surface temperature（average 26.8±0.4℃,n = 7）.These results suggest that TEX_（86） may record the sea surface mean annual temperature in the open ocean,while it likely records winter sea surface temperature in the shallower water.

关键词： Archaea GDGTs TEX86 Paleotemperature Northern South China Sea

ThE NON-IMPlANTABlE DEVICE OF SKElETAl MUSClE ChRONIC ElECTRICAl STIMUlATION

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Chinese Journal of Biomedical Engineering(English Edition) 1993年第3期2卷 99-99页

作者： W.M.huang~1 l.Yu~1 h.Kong~1 l.zhang~1 Q.Xu~21 Department of BME,Institute of Basic Medical Sciences,CAMS,Beijing 100005,China2 Beijing Institute of Medical Instrument

The clinical exploitation of electrically stimulated skeletal muscle circulation as-sistant(SMCA)is a new technology in later 80’*** is mainly used for advanced stageheart failure and progressive heart *** kind of heart diseases has a higherincidence and its death rate occupies first place in all kinds of heart *** such as heart transplanting is restricted by certain circumstances,so it cannot be used in *** way of SMCA can avoid many disadvantages such as ex-

关键词： disadvantages circumstances restricted electrically exploitation progressive skeletal stimulated looking stimulator

Combining multiple imperfect data sources for small area estimation:a Bayesian model of provincial fertility rates in Cambodia

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Statistical Theory and Related Fields 2019年第2期3卷 178-185页

作者： Junni l.zhang John Bryant Guanghua School of Management Center for Statistical Science and Center for Data SciencePeking UniversityBeijingPeople’s Republic of China Bayesian Demography limited ChristchurchNew Zealand

Demographic estimation becomes a problem of small area estimation when detaileddisaggregation leads to small cell *** usual difficulties of small area estimation are compounded when the available data sources contain measurement *** present a Bayesianapproach to the problem of small area estimation with imperfect data *** overall modelcontains separate submodels for underlying demographic processes and for measurement *** unknown quantities in the model,including coverage ratios and demographic rates,are estimated jointly via Markov chain Monte Carlo *** approach is illustrated usingthe example of provincial fertility rates in Cambodia.

关键词： Measurement error Bayesian hierarchical model coverage errors fertility Cambodia small area estimation