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Nanocrystallization-locked Network of Poly(styrene-6-isobutylene-6-styrene)-g-Polytetrahydrofuran Block Graft Copolymer

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Chinese Journal of Polymer Science 2021年第7期39卷 874-886页

作者： Hang-tian Zhang Zhi-tao Wei Fang Zhang tian Yang Yi-Xian Wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Sciences and EngineeringBeijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China

Poly(styrene-6-isobutylene-6-styrene)triblock copolymer(SIBS),a kind of thermoplastic elastomer with biocompatibility and biostability containing fully saturated soft segments,could be synthesized via living cationic copolymerization.A novel poly[(styrene-co-methylstyrene)-b-isobutylene-b-(styrene-co-methylstyrene)]-g-polytetrahydrofuran(M-SIBS-g-PTHF)block graft copolymer was prepared to increase the polarity and service temperature of SIBS by grafting polar PTHF segments onto SIBS.A series of the above block graft copolymers with average grafting numbers from 2 to 6 and molecular weights of PTHF branches ranging from 200 g·mol^(-1)to 4200 g·mol^(-1)were successfully synthesized via living cationic ring-opening polymerization of tetrahydrofuran(THF)coinitiated by *** introduction of PTHF branches led to an obvious microphase separation due to thermodynamic incompatibility among the three kinds of segments of polyisobutylene(PIB),polystyrene(PS)and ***,the microphase separation promotes the rearrangement of PTHF branches to form the nanocrystallization-locked physically cross-linked network after storage at room temperature for 2 months,leading to insolubility of the copolymers even in good *** melting temperature and enthalpy of PTHF nanocrystallization locked in hard domains of M-SIBS-g5-PTHF-1.1k block graft copolymer increased remarkably up to 153℃and 117.0 J·g^(-1)by 23℃and 11.6 J·g^-1(respectively after storage for long *** modulus(G′)is higher than loss modulus(G″)of M-SIBS-g-PTHF block graft copolymer at temperatures ranging from 100℃to 180℃,which is much higher than those of the SIBS triblock *** the best of our knowledge,this is the first example of high performance M-SIBS-g-PTHF block graft copolymers containing segments of PIB,PS and PTHF with nanocrystallization-locked architecture.

关键词： Poly(styrene-b-isobutylene-b-styrene) Polytetrahydrofuran Living cationic polymerization Block graft copolymers Nanocrystallization-locked network

Experimental and Modeling Study on C_(2)H_(2)Oxidation and Aromatics Formation at 1.2 MPa

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Journal of Thermal Science 2023年第2期32卷 866-880页

作者： tian Zhenyu tian Dongxu jin Kairu CHNE jintao jin Zhihao LI Wang DU Lijun YANG Jiuzhong Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

Oxidation of acetylene(C_(2)H_(2))has been investigated in a high-pressure jet-stirred reactor(HP-JSR)with equivalence ratiosΦ=0.5,1.0,2.0 and 3.0 in the temperature range of 650 K-900 K at 1.2 MPa.18 products and intermediates were analyzed qualitatively and quantitatively by gas chromatography(GC)and gas chromatography-mass spectrometry(GC-MS).Generally,withΦincreasing,the production of intermediates increases ***_(4),C_(2)H_(4),C_(2)H_(6),C_(3)H_(6)and C_(3)H_(8)were important intermediates,which were formed abundantly atΦ=*** light hydrocarbon intermediates could be an important reason for significant formation of cyclopentadiene,benzene,toluene and styrene atΦ=3.0.A detailed kinetic mechanism consisting of 299 species and 2041 reactions has been developed with reasonable predictions against the present data and previous results obtained at 0.1 *** to flux and sensitivity analysis,H and OH radicals play important roles in the consumption of C_(2)H_(2).The combinations among light hydrocarbons and their free radicals are the main generation pathways of aromatics.C_(3)H_(3),IC_(4)H_(5)and AC_(3)H_(5)are important precursors for the formation of *** comparing the results of atmospheric pressure and high pressure,it can be found that increasing the pressure is conducive to fuel consumption and aromatics generation.

关键词： acetylene high pressure oxidation jet-stirred reactor aromatics mechanism flux analysis sensitivity analysis

The synthesis,characterization and X-ray diffractometry structure of fluorine-containing cyclobis(paraquat-p-phenylene) tetracation

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Chinese Chemical Letters 2010年第6期21卷 633-636页

作者： Hai tao Xi tian tian Yi Xiao Qiang Sun Key Laboratory of Fine Petrochemical Engineering Jiangsu Polytechnic UniversityChangzhou 213164China

Two novel fluorine-containing cyclophanes 1 and 2 incorporating a 1,4-bismethylfluorophenylene subunits have been synthesized via the template-directed clipping methodology and their structure was characterized by ~1H NMR,^(13)C NMR, MALDI-TOF-MS and elemental analysis.X-ray diffraction analysis of the solid state molecular structure showed that the complex units are linked by non-classical C-H…F hydrogen bonding.

关键词： Fluorine-cotiaining cyclophanes 1,4-Bis(bromomethyl)-2-fluorobenzene Crystal structure Synthesis

Multi-Domain Decomposition Pseudospectral Method for Nonlinear Fokker-Planck Equations

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Communications on Applied Mathematics and Computation 2019年第2期1卷 231-252页

作者： tao Sun tian-jun Wang School of Statistics and Mathematics Shanghai Lixin University of Accounting and FinanceShanghai 201209China School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang 471003China

Results on the composite generalized Laguerre-Legendre interpolation in unbounded domains are established. As an application,a composite Laguerre-Legendre pseudospectral scheme is presented for nonlinear Fokker-Planck equations on the whole line. The convergence and the stability of the proposed scheme are proved. Numerical results show the efficiency of the scheme and conform well to theoretical analysis.

关键词： Composite generalized Laguerre-Legendre pseudospectral approximation Nonlinear Fokker-Planck equations defined on unbounded domains Multi-domain decomposition pseudospectral method

Friction identification and compensation design for precision positioning

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Advances in Manufacturing 2017年第2期5卷 120-129页

作者： Feng-tian Li Li Ma Lin-tao Mi You-Xuan Zeng Ning-Bo jin Ying-Long Gao School of Mechatronic Engineering and Automation Shanghai University Shanghai 200072 People's Republic of China

Precision positioning systems driven by linear motors are vulnerable to force disturbances owing to the reduction of gear transmission. The friction, included in the disturbance, can be modeled and compensated to improve the servo performance. This paper proposes a modified Stribeck friction model （SFM） and an optimization algorithm for consistency with the positioning platform. The compensators based on the friction model and disturbance observer （DOB） are simulated. The simulation results show that as compared with the DOB compensator （the velocity recovers by 5.19%）, the friction model based compensator （the velocity recovers by 10.66%） exhibits a better performance after adding the disturbance. Moreover, compensation comparisons among the Coulomb friction, traditional SFM, and modified SFM are performed. The experimental results show that the following error with modified SFM compensation improves by 67.67% and 51.63% at a speed of 0.005 m/s and 0.05 m/s, compared with the Coulomb friction compensation. This demonstrates that the proposed model, optimization algorithm, and compensator can reduce the following error effectively.

关键词： Precision positioning Friction compensation Identification Modeling

Effects of Mo Contents in Matrix on Microstructure and Properties of Vanadium Carbide Coating Formed by Thermal Diffusion Treatment

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Journal of Iron and Steel Research International 2014年第1期21卷 104-108页

作者： Zhi-tao HUANG Wen-huai tian School of Materials Science and Engineering University of Science and Technology Beijing

Thermal diffusion salt-bath vanadizing was finished for Crl2MoV die steel, in order to investigate the properties of vanadium carbide coatings related with the Mo contents in Crl2MoV die steel. Scanning electron micro- scopic observation reveals that Mo can decrease the growth rate of coating as a carbide forming element. Besides, Mo element can promote grain refinement of the coating. X-ray diffraction analysis shows that the different Mo contents have no influence on the phase structure of the coatings. Energy dispersive spectrum analysis and mechanical properties test show that Mo can diffuse into the coating and make a strengthening effect on the coating.

关键词： vanadium carbide salt-bath carbide forming element grain refinement mechanical property

Deterministic generation of multi-photon bundles in a quantum Rabi model

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Science China(Physics,Mechanics & Astronomy) 2023年第2期66卷 1-12页

作者： Cheng Liu jin-Feng Huang Lin tian Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China School of Natural Sciences University of CaliforniaMerced 95343USA

Multi-photon bundle states are crucial for a broad range of applications such as quantum metrology,quantum lithography,quantum communication,and quantum *** we propose a scheme that generates multi-photon bundles via virtual excitations in a quantum Rabi *** approach utilizes a Ξ-type three-level atom,where the upper two levels are coupled to a cavity field to form a quantum Rabi model with ultrastrong coupling,and the transition between the lower two levels is driven by two sequences of Gaussian *** show that the driving pulses induce deterministic emission of multiple photons from the eigenstates of the quantum Rabi model via the stimulated Raman adiabatic passage technique,and hence can create bundles of multiple photons on-demand in the cavity output *** calculate the generalized second-order correlation functions of the output photons,which reveal that the emitted photons form antibunched multi-photon bundles.

关键词： field quantum bundles

Brain organoids are new tool for drug screening of neurological diseases

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Neural Regeneration Research 2023年第9期18卷 1884-1889页

作者： jin-Qi Zhou Ling-Hui Zeng Chen-tao Li Da-Hong He Hao-Duo Zhao Yan-Nan Xu Zi-tian jin Chong Gao School of Medicine Institute of Brain and Cognitive ScienceHangzhou City UniversityHangzhouZhejiang ProvinceChina Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province School of MedicineHangzhou City UniversityHangzhouZhejiang ProvinceChina

At the level of in vitro drug screening,the development of a phenotypic analysis system with highcontent screening at the core provides a strong platform to support high-throughput drug *** are few systematic reports on brain organoids,as a new three-dimensional in vitro model,in terms of model stability,key phenotypic fingerprint,and drug screening schemes,and particula rly rega rding the development of screening strategies for massive numbers of traditional Chinese medicine *** paper reviews the development of brain organoids and the advantages of brain organoids over induced neurons or cells in simulated *** paper also highlights the prospects from model stability,induction criteria of brain organoids,and the screening schemes of brain organoids based on the characteristics of brain organoids and the application and development of a high-content screening system.

关键词： brain organoids disease modeling high-content system multiple omic analysis network pharmacology neurodegeneration phenotypic fingerprint psychiatric diseases stem cells traditional Chinese medicine drug screening

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水稻软盘毯状苗分离机设计与试验

农机化研究 2025年第2期47卷 86-90页

作者：赵语轩毛欣衣淑娟陶桂香田永久黑龙江八一农垦大学程学院黑龙江大庆163319 黑龙江省水稻生态育秧装置及全程机械化工程技术研究中心黑龙江大庆163319

目前,水稻种植环节中育秧环节与移栽环节之间的水稻苗盘分离环节的机械化程度相较于其他环节较为薄弱。为提高水稻全程机械化作业水平,降低生产成本,设计了一种适用于水稻毯状苗与塑料软盘分离的机械装置,主要由输送机构、分离机构、扶... 详细信息

目前,水稻种植环节中育秧环节与移栽环节之间的水稻苗盘分离环节的机械化程度相较于其他环节较为薄弱。为提高水稻全程机械化作业水平,降低生产成本,设计了一种适用于水稻毯状苗与塑料软盘分离的机械装置,主要由输送机构、分离机构、扶苗机构、集苗机构、动力系统和机架组成。对装置的结构及工作原理进行了描述,分析确定各个机构的结构参数。以分离率、茎叶损伤率、基质损伤率为试验指标进行苗盘分离试验,结果表明:水稻软盘毯状苗分离机作业效果较好,分离成功率在95%以上,能够降低生产成本,提高生产效率;茎叶损伤率及基质损伤率均在3%以下,保证后续水稻毯状苗移栽工作的顺利进行,较小的茎叶损伤与基质损伤也保证了后续水稻生长过程中不会受到较大的影响,满足水稻育秧农艺要求和水稻工厂化技术规范要求。

关键词：水稻毯状苗分离机机械化生产