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Journal of Materials Science & Technology 1999年第2期15卷 169-177页

作者： song, ms Zhou, W Hu, GX Hu, LJ Beijing Univ Chem Technol Inst Polymer Mat Beijing 100029 Peoples R China Harbin Inst Technol Dept Appl Chem Harbin 150001 Peoples R China

A double-network model is established, which consists of the segments, E and A-constituent chains, the polymeric chains entangled with other ones by multi-entanglement and polymeric chains connected to a great number of destructible particles by multi-adsorption, based on which the E and A-constituent chains can be recreated and released dynamically. The distribution function of the end-to-end vector, the statistical distribution function of conformation for two kinds of chains in the multi-entanglement and multi-adsorption states and their number of polymeric chains are calculated by the combination of statistical mechanics and kinetics. Then the viscoelastic free energies of deformation for two kinds of the networks and suspensions are calculated by Boltzmann's statistical theory. Also, elastic modulus and memory function for two kinds of the network and suspensions are derived. Consequently, a new molecular theory df the non-linear viscoelasticity for polymeric suspensions is proposed, and the constitutive equation and material function with yielding and thinning for the polymeric suspensions in different flow fields are derived from this theory.

关键词： Polymers

Rheological Behaviors of Polymer Melts and Concentrated Solutions Part VI: Comparison of the Material Functions with Yielding and Thinning for Polymeric Suspensions with Their Experimental Values

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Journal of Materials Science & Technology 1999年第3期15卷 251-252,523-262页

作者： song, ms Zhou, W Hu, GXX Hu, LJ Beijing Univ Chem Technol Res Inst Polymer Mat Beijing 100029 Peoples R China Harbin Inst Technol Dept Appl Chem Harbin 150001 Peoples R China

The memory function and elastic modulus were introduced into the O-W-F type of constitutive equations with the Cauchy-Green and Finger tensors for simple fluid, and then the concrete constitutive equation and material function for polymeric suspensions in the different flow fields were formulated: 1) Viscosity and first normal-stress difference coefficient in the shear flow field; 2) Tensile viscosity at the uni-axial elongation flow field; and 3) Dynamic viscosity and modulus in the dynamic field. Then the dependence of the material function on the deformation rate and weight fraction of fillers was discussed, and the shear flow curves with four characteristic regions ( I-low shear rate plateau region, II- apparent yielding region, ill-intermediate rate plateau region, and lV-shear thinning region.) were explained theoretically. Finally, it was verified by a number of experimental values for the rheological suspensions and the viscoelastic and mechanical behaviors can be predicted by the molecular theory of non-linear viscoelasticity for polymeric suspension;.

关键词： VISCOSITY LIQUIDS

P-wave velocities of alkaline olivine basalt at high pressure and temperature and its controlling factors

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Chinese Science Bulletin 1997年第9期42卷 761-764页

作者： song, ms Xie, HS Zhang, YM Hou, W Xu, J Xu, YS Earth’s Interior Material Laboratory Institute of Geochemistry Chinese Academy of Sciences Guiyang China Institute of Earth Science Academia Sinica Taibei China

SEISMIC wave inversion is one of the most important means for us to recognize the compositionand structure of the Earth’s *** the experimental techniques of elastic wave ve-locity measurement at in situ high pressure... 详细信息

关键词： high pressure and temperature alkaline olvine basalt P-wave velocity softening effect phase transformation.

Measurement of electrical conductivity of 0.001 mol NaCl solution under high pressures

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Chinese Science Bulletin 1997年第18期42卷 1563-1566页

作者： Zheng, HF Xie, HS Xu, YS song, ms Guo, J Zhang, YM Department of Geology Peking University Beijing China Institute of Geochemistry Chinese Academy of Sciences Guiyang China

The experiments were carried out in a YJ-3000 ton press fitted with a wedge-type cubic anvil. The samples were pressed using pyropgyllite as the pressure medium. The conductance cell for the experiments was made of Te... 详细信息

关键词： electrical conductivity high pressure NaCI solution.

The Persistence and Zonal Scale of Atmospheric Dipolar Modes

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Advances in Atmospheric Sciences 2024年第3期41卷 478-492页

作者： Jie song State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(Dms). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric Dms with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric Dms with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric Dms have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral Dms are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term

Identification of Linear Systems Using Binary Sensors with Random Thresholds

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Journal of Systems Science & Complexity 2024年第3期37卷 907-923页

作者： HUANG Zhiyong song Qijiang School of Mathematics Renmin University of ChinaBeijing 100872China School of Mathematics Sino-French InstituteRenmin University of ChinaBeijing 100872China

In this paper,the problem of identifying autoregressive-moving-average systems under random threshold binary-valued output measurements is *** the help of stochastic approximation algorithms with expanding truncations,the authors give the recursive estimates for the parameters of both the linear system and the binary *** reasonable conditions,all constructed estimates are proved to be convergent to the true values with probability one,and the convergence rates are also established.A simulation example is provided to justify the theoretical results.

关键词： α-mixing binary sensor quantized system stochastic approximation stochastic thresh-old strongly consistent system identification

Self-healing Ga-based liquid metal/alloy anodes for rechargeable batteries

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Nano Research 2024年第3期17卷 1366-1383页

作者： Meijia song Zhonghua Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212000China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJingshi Road 17923Jinan 250061China

With the rapid development of electronics,electric vehicles,and grid energy storage stations,higher requirements have been put forward for advanced secondary *** metal/alloy electrodes have been considered as a promising development direction to achieve excellent electrochemical performance in metal-ion batteries,due to their specific advantages including the excellent electrode kinetics and self-healing ability against microstructural electrode *** conventional liquid batteries,high temperatures are needed to keep electrode liquid and ensure the high conductivity of molten salt electrolytes,which also brings the corrosion and safety ***-based metal/alloys,which can be operated at or near room temperature,are potential candidates to circumvent the above *** this review,the properties and advantages of Ga-based metal/alloys are ***,Ga-based liquid metal/alloys as anodes in various metal-ion batteries are reviewed in terms of their self-healing ability,battery configurations,working mechanisms,and so ***,some views on the future development of Ga-based electrodes in batteries are provided.

关键词： metal-ion batteries Ga-based liquid metal/alloy anodes self-healing capability room temperature

The learning curve for transurethral enucleation with bipolar energy for benign prostate hyperplasia:a single-surgeon experience of 494 patients

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Asian Journal of Andrology 2024年第3期26卷 288-294页

作者： Byeongdo song Sang Hun song Seong Jin Jeong Department of Urology Seoul National University Bundang HospitalSeongnam 13620Korea Department of Urology Seoul National University College of MedicineSeoul 03080Korea

This study was performed to investigate the learning curve of transurethral enucleation with bipolar energy(TUEB)for benignprostatic *** study involved 494 consecutive patients who underwent TUEB for benign prostatic hyperplasia fromAugust 2018 to March 2022 by one surgeon(SJJ,Seoul National University Bundang Hospital,Seongnam,Korea).The patientswere followed up at 1 week,1 month,3 months,and 6 months *** evaluate the learning curve of TUEB,perioperativeparameters including the enucleation ratio(enucleated tissue weight/transitional zone volume),TUEB efficiency(enucleatedtissue weight/operation time),and enucleation efficiency(enucleated tissue weight/enucleation time)were *** and postoperative complications were also assessed,including the International Prostate Symptom Score(IPSS),IPSSquality-of-life(QoL)score,and uroflowmetry *** patients’median age was 72(interquartile range[IQR]:66–78)years,and the estimated prostate volume and transitional zone volume were 63.0(IQR:46.0–90.6)ml and 37.1(IQR:24.0–60.0)ml,*** enucleation ratio,TUEB efficiency,and enucleation efficiency were 0.60(IQR:0.46–0.54)g ml−1,0.33(IQR:0.22–0.46)g min−1,and 0.50(IQR:0.35–0.72)g min−1,respectively,plateauing after 70 *** functional outcomes,including total IPSS,IPSS QoL score,and uroflowmetry outcomes,significantly improved at 6 months after TUEB(all P<0.05),but without significant differences over the learning ***-five(13.2%)patients developed complications after TUEB,21.5%of whom experienced major complications(Clavien–Dindo grade≥3).The rate of major complications declined as the number ofTUEB cases increased(P=0.013).Our results suggest that the efficiency of TUEB stabilized within 70 procedures.

关键词： benign prostate hyperplasia learning curve perioperative efficiency prostate transurethral enucleation with bipolar energy

Optimizing multi-parameter distributed fiber sensors:a hybrid Rayleigh-Brillouin-Raman System approach

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Light(Science & Applications) 2024年第3期13卷 393-395页

作者： Kwang Yong song Dept.of Physics Chung-Ang University84 Heukseok-roDongjak-guSeoul 06974Korea

An optimized single-end hybrid Rayleigh,Brillouin,and Raman distributed fiber sensing system has been developed for simultaneous measurement of multiple *** system integrates 3-bit pulse coding for the Raman signal and the Brillouin amplification of the Rayleigh-backscattered signal,discriminating strain,temperature,and vibration using a single sensing fiber.

关键词： fiber Rayleigh signal

Berry-Esseen bounds for self-normalized sums of locally dependent random variables

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Science China Mathematics 2024年第11期67卷 2629-2652页

作者： Zhuo-song Zhang Department of Statistics and Data Science Southern University of Science and Technology

The Berry-Esseen bound provides an upper bound on the Kolmogorov distance between a random variable and the normal *** this paper,we establish Berry-Esseen bounds with optimal rates for self-normalized sums of locally dependent random variables,assuming only a second-moment *** proof leverages Stein's method and introduces a novel randomized concentration inequality,which may also be of independent interest for other *** main results have applied to self-normalized sums of m-dependent random variables and graph dependency models.

关键词： Berry-Esseen bounds self-normalized sums localdependence $m$-dependence graph dependency

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