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STRUCTURE EVOluTION OF polymer CHAINS FOR NECKING FORMATION IN HIGH-SPEED FIBER SPINNING PROCESS

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chinese Journal of polymer science 2006年第1期24卷 1-11页

作者： Hong Zheng Wei Yu Hong-bin Zhang and Chi-xing Zhou department of polymer Materials science & engineering,shanghai jiao tong university,shanghai 200240,china department of polymer Materials science & engineering Shanghai Jiao Tong University Shanghai 200240 China

Finite element method is used to simulate the high-speed melt spinning process, based on the equation system proposed by Doufas et al. Calculation predicts a neck-like deformation, as well as the related profiles of velocity, diameter, temperature, chain orientation, and crystallinity in the fiber spinning process. Considering combined effects on the process such as flow-induced crystallization, viscoelasticity, filament cooling, air drag, inertia, surface tension and gravity, the simulated material flow behaviors are consistent with those observed for semi-crystalline polymers under various spinning conditions, The structure change of polymer coils in the necking region described by the evolution of conformation tensor is also investigated. Based on the relaxation mechanism of macromolecules in flow field different types of morphology change of polymer chains before and in the neck are proposed, giving a complete prospect of structure evolution and crystallization of semi-crystalline polymer in the high speed fiber spinning process.

关键词： Semi-crystalline polymer Crystallization High-speed Fiber Spinning Process Conformation Finite Element Method (FEM).

A RHEOLOGICAL MOdeL FOR polymer MELTS WITH INTERNAL STRUCTURE IN FLOW FIELDS

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chinese Journal of polymer science 1999年第2期17卷 151-158页

作者： Chi-Xing Zhou department of polymeric Materials science and engineering, shanghai jiao tong university, shanghai 200240, china 上海交通大学高分子材料科学与工程系上海

Conceptually, an imagined conformation ellipsoid is supposed to represent the shape of a polymer chain for polymer melts in flow fields and to be equivalent to the volume element in a mathematical sense in continuum mechanics. A power law dependence of shear modulus of polymer melts on detC, referred to as envelope volume, is proposed. Based on those assumptions and the non-linear relation of shear modulus, a phenomenological viscoelastic model is derived. The model is tested in simple shear flow, simple elongational flow, oscillatory shear flow, and relaxation process after flow suddenly stopped. The results show that the model works well to predict the change of internal structure and viscoelastic performance of polymer melts in flow fields.

关键词： polymer melts rheological model polymer conformation flow fields

Rational design of vitamin C/defective carbon van der Waals heterostructure for enhanced activity,durability and storage stability toward oxygen reduction reaction

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Journal of Energy chemistry 2024年第1期88卷 103-111,I0003页

作者： Ruiqi Cheng Kaiqi Li Huanxin Li Tianshuo zhao Yibo Wang Qingyue Xue jiao Zhang Chaopeng Fu shanghai key laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Christopher Ingold laboratory Department of ChemistryUniversity College LondonLondon WC1H 0AJUK department of chemistry Physical&Theoretical Chemistry LaboratoryUniversity of OxfordSouth Parks RoadOxford OX13QZUK

Metal-free defective carbon materials with abundant active sites have been widely studied as low-cost and efficient oxygen reduction reaction(ORR)electrocatalysts in metal-air ***,the active sites in defective carbon are easily subjected to serious oxidation or hydroxylation during ORR or storage,leading to rapid degradation of ***,we design a van der Waals heterostructure comprised of vitamin C(VC)and defective carbon(DC)to not only boost the activity but also enhance the durability and storage stability of the DC-VC *** formation of VC van der Waals between DC and VC is demonstrated to be an effective strategy to protect the defect active sites from oxidation and hydroxylation degradation,thus significantly enhancing the electrochemical durability and storage anti-aging ***,the DC-VC van der Waals can reduce the reaction energy barrier to facilitate the *** findings are also confirmed by operando Fourier transform infrared spectroscopy and density functional theory *** is necessary to mention that the preparation of this DC-VC electrocatalyst can be scaled up,and the ORR performance of the largely produced electrocatalyst is demonstrated to be very ***,the DC-VC-based aluminum-air batteries display very competitive power density with good performance maintenance.

关键词： Van der Waals heterostructure Oxygen reduction reaction Stability Scalable production Aluminum-air battery

Preparation of grain size controlled boron-doped diamond thin films and their applications in selective detection of glucose in basic solutions

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science china chemistry 2010年第6期53卷 1378-1384页

作者： zhao JianWen1,2,WANG JinLiang3,ZHI JinFang3 & ZHANG ZhiMing4 1College of chemistry and Chemical engineering,Jishou university,Jishou 416000,china 2Schools of Materials science and engineering,Nanyang Technological university,639798,Singapore 3laboratory of Organic Optoelectronic Functional Materials and Molecular engineering,Technical institute of physics and chemistry & Graduate university of chinese academy of sciences,beijing 100080,china 4Research institute of Micro-Nano science and Technology,shanghai jiao tong university,shanghai 200030,china College of chemistry and Chemical engineering Jishou University Jishou China Schools of Materials science and engineering Nanyang Technological University Singapore Singapore laboratory of Organic Optoelectronic Functional Materials and Molecular engineering Technical Institute of Physics and Chemistry & Graduate University of Chinese Academy of Sciences Beijing China Research institute of Micro-Nano science and Technology Shanghai Jiao Tong University Shanghai China

Boron-doped diamond (BDD) thin films with different crystal grain sizes were prepared by controlling the reacting gas pressure using hot filament chemical vapor deposition (HFCVD).The morphologies and structures of the prepared diamond thin films were characterized by scanning electron microscopy (SEM) and Raman *** electrochemical responses of K4Fe(CN)6 on different BDD electrodes were *** results suggested that electron transfer was faster at the boron-doped nanocrystalline diamond (BDND) thin film electrodes in comparison with that at other BDD thin film *** prepared BDD thin film electrodes without any modification were used to directly detect glucose in the basic *** results showed that the as-prepared BDD thin film electrodes exhibited good selectivity for detecting glucose in the presence of ascorbic acid (AA) and uric acid (UA).The higher sensitivity was observed on the BDND thin film grown on the boron-doped microcrystalline diamond (BDMD) thin film surface,and the linear response range,sensitivity and the low detection limit were 0.25–10 mM,189.1 μA mmol-1 cm-2 and 25 μM (S/N=3) for glucose in the presence of AA and UA,respectively.

关键词： diamond thin films electrochemical properties selective glucose detection

In-situ transformed Mott-Schottky heterointerface in silver/manganese oxide nanorods boosting oxygen reduction,oxygen evolution,and hydrogen evolution reactions

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Nano Research 2024年第5期17卷 3622-3632页

作者： Ruiqi Cheng Kaiqi Li Huanxin Li Fengzhan Sun Xiaoqian He Tianshuo zhao jiao Zhang Chaopeng Fu shanghai key laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Christopher Ingold laboratory Department of ChemistryUniversity College LondonLondon WC1H 0AJUK department of chemistry Physical&Theoretical Chemistry LaboratoryUniversity of OxfordSouth Parks RoadOxford OX13QZUK Center of Hydrogen science School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The development of non-platinum group metal(non-PGM)and efficient multifunctional electrocatalysts for oxygen reduction reaction(ORR),oxygen evolution reaction(OER),and hydrogen evolution reaction(HER)with high activity and stability remains a great ***,by in-situ transforming silver manganese composite oxide heterointerface into boosted Mott-Schottky heterointerface through a facile carbon reduction strategy,a nanorod-like silver/manganese oxide with superior multifunctional catalytic activities for ORR,OER and HER and stability was *** nanorod-like silver/manganese oxide with Mott-Schottky heterointerface(designated as Ag/Mn_(3)O_(4))exhibits an ORR half-wave potential of 0.831 V(***)in 0.1 M KOH,an OER overpotential of 338 mV and a HER overpotential of 177 mV at the current density of 10 mA·cm^(-2)in 1 M KOH,contributing to its noble-metal benchmarks comparable performance in aqueous aluminum-air(Al-air)battery and laboratorial overall water splitting electrolytic ***,in-situ electrochemical Raman and synchrotron radiation spectroscopic measurements were conducted to further illustrate the catalytic mechanism of Ag/Mn_(3)O_(4)Mott-Schottky heterointerface towards various electrocatalytic *** the heterointerface,the Ag phase serves as the electron donor and the active phase for ORR and HER,while the Mn_(3)O_(4)phase serves as the electron acceptor and the active phase for OER,*** work deepens the understanding of the Mott-Schottky effect on electrocatalysis and fills in the gap in fundamental physical principles that are behind measured electrocatalytic activity,which offers substantial implications for the rational design of cost-effective multifunctional electrocatalysts with Mott-Schottky effect.

关键词： heterointerface electron donor-acceptor pair electrocatalyst Al-air battery water splitting

Prediction of the short-term efficacy of anti-VEGF therapy for neovascular age-related macular degeneration using optical coherence tomography angiography

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Eye and Vision 2024年第3期10卷 21-30页

作者： Huixun Jia Bing lu Zhi zhao Yang Yu Fenghua Wang Minwen Zhou Xiaodong Sun department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong University School of Medicine100 Hai Ning RoadShanghai200080People’s Republic of China shanghai key laboratory of Ocular Fundus Diseases ShanghaiChina National Clinical Research Center for Eye Diseases ShanghaiChina shanghai engineering Center for Visual science and Photomedicine ShanghaiChina shanghai engineering Center for Precise Diagnosis and Treatment of Eye Diseases ShanghaiChina Clinical Research institute Shanghai Jiao Tong University School of MedicineShanghaiChina

Background To evaluate whether the specific choroidal neovascularization(CNV)characteristics measured using optical coherence tomography angiography(OCTA)can predict the 6-month prognosis of neovascular age-related macular degeneration(nAMD)after anti-vascular endothelial growth factor(anti-VEGF)*** Patients with type 1,type 2,or mixed-type neovascularization(NV)were prospectively *** underwent an initial loading phase of three consecutive monthly intravitreal injections of Conbercept(0.5 mg)and were switched to a pro re nata(PRN)treatment *** images were evaluated for eyes that underwent follow-up assessments for more than 6 *** lesions were manually segmented,and the CNV area,vessel area,greatest vascular caliber(GVC),and greatest linear dimension(GLD)were compared between responders and *** masked graders independently measured the above-mentioned parameters using OCTA,and consistency was assessed using the intraclass correlation coefficient(ICC)*** logistic regression analysis was performed to evaluate the effect of a 3-month change in the CNV area,GLD,and GVC on the 6-month response to anti-VEGF *** Among the 60 eyes of 60 patients with nAMD,39 were responders and 21 were *** proportion of CNV types was significantly different between responders and non-responders(P=0.009).Patients with type 2 or mixed NV seemed more likely to respond to the treatment(28.2%vs.0.0%,and 30.8%vs.23.8%,respectively).The change in GVC showed a significant difference between responders(−4.98±17.17μm)and non-responders(11.01±14.10μm)after three monthly intravitreal anti-VEGF *** logistic regression analysis showed that only the change in GVC remained significant after controlling for baseline GVC,injection number,and CNV type(adjusted OR=1.083;P=0.008).Conclusions Type 2 and mixed-type NV were significantly associated with a better response to anti-VEGF *** i

关键词： Age-related macular degeneration Choroidal neovascularization Optical coherence tomography angiography Anti-VEGF

Conditional Entropy of Partitions on Quantum Logic

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Communications in Theoretical physics 2007年第7期48卷 11-13页

作者： zhao Yue-Xu institute of Applied Mathematics and engineering Computation,Hangzhou Dianzi university,Hangzhou 310018,chinaMA Zhi-Hao department of Mathematics,shanghai jiao tong university,shanghai 200240,china institute of Applied Mathematics and engineering Computation Hangzhou Dianzi University Hangzhou 310018 China department of Mathematics Shanghai Jiao Tong University Shanghai 200240 China

A construction of conditional entropy of partitions on quantum logic is given,and the properties ofconditional entropy are investigated.

关键词： state density operator projector conditional entropy quantum logic lattice

AI for science: Predicting infectious diseases

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Journal of Safety science and Resilience 2024年第2期5卷 130-146页

作者： Alexis Pengfei zhao Shuangqi Li Zhidong Cao Paul Jen-Hwa Hu jiaojiao Wang Yue Xiang Da Xie Xi lu institute of Automation Chinese Academy of SciencesUniversity of Chinese Academy of SciencesBejing 100090China Systems engineering Cornll UniversityIthacaNY 14853USA David Eccles School of Business the University of UtahUtahUSA Collge of Electrical engineering Sichuan UniversityChina department of Electrical engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Electrical engineering Southeast UniversityNanjing 210096China

The global health landscape has been persistently challenged by the emergence and re-emergence of infectious *** epidemiological models,rooted in the early 2oth century,have provided foundational in-sights into disease ***,the intricate web of modern global interactions and the exponential growth of available data demand more advanced predictive *** is where AI for science(AI4S)comes into play,offering a transformative approach by integrating artificial intelligence(Al)into infectious disease *** paper elucidates the pivotal role of AI4s in enhancing and,in some instances,superseding tradi-tional epidemiological *** harnessing AI's capabilities,AI4S facilitates real-time monitoring,sophisticated data integration,and predictive modeling with enhanced *** comparative analysis highlights the stark contrast between conventional models and the innovative strategies enabled by *** essence,Al4S represents a paradigm shift in infectious disease *** addresses the limitations of traditional models and paves the way for a more proactive and informed response to future *** we navigate the complexities of global health challenges,Al4S stands as a beacon,signifying the next phase of evolution in disease prediction,characterized by increased accuracy,adaptability,and efficiency.

关键词： AI for science(AI4S) Data integration Global healthchallenges Infectious disease prediction Predictive modeling Real-timemonitoring

Modeling the Interaction between Vacancies and Grain Boundaries during Ductile Fracture

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Computer Modeling in engineering & sciences 2024年第8期140卷 2019-2034页

作者： Mingjian Li Ping Yang Pengyang zhao department of engineering Mechanics School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

The experimental results in previous studies have indicated that during the ductile fracture of pure metals,vacancies aggregate and form voids at grain ***,the physical mechanism underlying this phenomenon remains not fully *** study derives the equilibrium distribution of vacancies analytically by following thermodynamics and the micromechanics of crystal *** derivation suggests that vacancies cluster in regions under hydrostatic compression to minimize the elastic strain ***,a finite element model is developed for examining more general scenarios of interaction between vacancies and grain *** model is first verified and validated through comparison with some available analytical solutions,demonstrating consistency between finite element simulation results and analytical solutions within a specified numerical accuracy.A systematic numerical study is then conducted to investigate the mechanism that might govern the micromechanical interaction between grain boundaries and the profuse vacancies typically generated during plastic *** simulation results indicate that the reduction in total elastic strain energy can indeed drive vacancies toward grain boundaries,potentially facilitating void nucleation in ductile fracture.

关键词： Ductile fracture vacancy grain boundary micromechanical finite element method