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SYNTHESIS OF NOVEL THIOPHENEDIMETHYLENE BRIDGED HOMOBINUCLEAR METALLOCENES AND THEIR CATALYTIC PROPERTIES FOR ETHYLENE POLYMERIZATION

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Chinese Journal of Polymer Science 2006年第1期24卷 21-27页

作者： Xi-jie Liu Jun-quan Sun Hai-ying Zhang Xiao-hui Xiao and Feng lin Department of Chemical Engineering,College of Material and Chemical Engineering,zhejiang university,hangzhou 310027,china Department of Chemical Engineering College of Material and Chemical Engineering Zhejiang University Hangzhou 310027 China

By treating disodium（thiophenedimethylene）dicyclopentadienide C4H2S（CH2C5H4Na）2 with two equivalent of CpTiCl3 or CpZrC13 DME at 0℃ in THF, two new thiophenedimethylene bridged binuclear metallocenes [Cl2MC5H5][C5H4CH2C4H2SCH2C5H4][C5H5MCl2] （M = Ti 3, M = Zr 4） were synthesized in high yield and their structures were characterized by ^1H-NMR. These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane （MAO）. The effects of polymerization temperature, time, concentration of catalyst, molar ratio of MAO/Cat on polymerization were studied in detail. The catalytic activities of thiophenedimethylene bridged binuclear metallocene catalysts （3, 4） reached 2.44 × 10^5 g PE mol^-1 cat^-1· h^-1, 9.61 × 10^5 g PE mol^-1 · cat^-1· h^-1 respectively, which are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes （Cp2TiCl2 and Cp2ZrCl2）. The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts （3, 4） and by mononuclear metallocene catalyst have only single peak, but the former （MWD = 3.5-4.7） is obviously broader than the latter （MWD = 2.0-2.2）.

关键词： Binuclear metallocene Thiophenedimethylene bridged Ethylene polymerization.

Emerging role of lncRNAs as mechanical signaling molecules in mechanotransduction and their association with Hippo-YAP signaling:a review

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Journal of zhejiang university-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 280-292页

作者： Siyi lin Xinyu HE Ying WANG Yu CHEN Aifu lin College of Medicine Zhejiang UniversityHangzhou 310058China College of Life Sciences Zhejiang UniversityHangzhou 310058China Cancer Center Zhejiang UniversityHangzhou 310058China Key Laboratory for Cell and Gene Engineering of zhejiang Province Hangzhou 310058China International School of Medicine International Institutes of Medicinethe Fourth Affiliated Hospital of Zhejiang University School of MedicineYiwu 322000China Key Laboratory of Cancer Prevention and Intervention China National Ministry of EducationHangzhou 310058China Future Health Laboratory Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100China

Cells within tissues are subject to various mechanical forces,including hydrostatic pressure,shear stress,compression,and *** mechanical stimuli can be converted into biochemical signals through mechanoreceptors or cytoskeleton-dependent response processes,shaping the microenvironment and maintaining cellular physiological *** studies have demonstrated the roles of Yes-associated protein(YAP)and its homolog transcriptional coactivator with PDZ-binding motif(TAZ)as mechanotransducers,exerting dynamic influence on cellular phenotypes including differentiation and disease *** regulatory function entails the involvement of the cytoskeleton,nucleoskeleton,integrin,focal adhesions(FAs),and the integration of multiple signaling pathways,including extracellular signal-regulated kinase(ERK),wingless/integrated(WNT),and Hippo ***,emerging evidence substantiates the implication of long non-coding RNAs(lncRNAs)as mechanosensitive molecules in cellular *** this review,we discuss the mechanisms through which YAP/TAZ and lncRNAs serve as effectors in responding to mechanical ***,we summarize and elaborate on the crucial signal molecules involved in mechanotransduction.

关键词： YAP/TAZ Long non-coding RNA(lncRNA) Mechanotransduction F-actin

NUMERICAL SIMULATION ON VELOCITIES OF TWO INTERACTING FIBERS IN FIBER SUSPENSION

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Journal of Hydrodynamics 2003年第3期15卷 10-16页

作者： lin Jian-zhong, Bao Fu-bing, Zhang Zhi-chao Department of Mechanics, State Key Laboratory of Fluid Power Transmission and Control, zhejiang university, hangzhou 310027, china, Lab. of Fluid Power Transmission Dept. of Mech. Zhejiang Univ. Hangzhou 310027 China

A mathematical model was put forward to describe the mechanical interactionsof two contacting fibers, then a numerical simulation was carried out. The results of the simulationaccord with experimental results well. It turns out that the initial contacting point and theinitial orientation of the settling fiber have much effect on the translational and rotationalvelocities of the settling fiber, along with the increase in the length or the decrease in theradius of the fiber, the translational and rotational velocities of the settling fiber decrease; thesame trend remains when the viscosity of the solvent increases or the density of the fiberdecreases.

关键词： fiber suspension mechanical interaction numerical simulation

Local times of N-parameter Gaussian processes

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Progress in Natural Science:Materials International 2005年第2期 13-19页

作者： lin Zhengyan1* and CHENG Zongmao 1,2(1. Department of mathematics, zhejiang university, hangzhou 310028, china 2. hangzhou Institute of Electronics and Engineering, hangzhou 310012, china) Department of mathematics Zhejiang UniversityHangzhou 310028China Department of mathematics Zhejiang UniversityHangzhou 310028China hangzhou Institute of Electronics and Engineering Hangzhou 310012China

An N-parameter Gaussian stationary process X=｛X(t): t∈RN+｝ is introduced and the existence and joint continuity of its local times is presented. And the moments of local times are estimated. Furthermore moduli of c... 详细信息

关键词： N-parameter Gaussian process local time moduli of continuity large increments.

Recent progress in self-propelled particles

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Journal of Hydrodynamics 2024年第1期36卷 61-77页

作者： Zhen-yu Ouyang Jian-zhong lin Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo315201China Department of Mechanics State Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou310027China

Self-propelled particles are commonly found in a large number of planktonic organisms such as bacteria,fungi,and algae in nature,and researchers have taken a long interest in exploring their swimming mechanisms for more than a *** in the past 20 years,with the development of computational fluid dynamics and flow display technology,as well as the need for the design of synthetic self-propelled particles and micro-swimming devices,self-propelled particles have become the forefront and hotspot of current research in the field of fluid *** paper first introduces the swimming characteristics of common self-propelled particles,leading to a classic“squirmer”type self-propelled particle *** this basis,a systematic introduction and summary of the theoretical and numerical simulation research of“squirmer”will be ***,the main challenges and opportunities faced by the current research will be summarized.

关键词： Self-propelled particles multiphase flow hydrodynamic interaction

A Review on the Mullins Effect in Tough Elastomers and Gels

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Acta Mechanica Solida Sinica 2024年第2期37卷 181-214页

作者： lin Zhan Shaoxing Qu Rui Xiao MOE Key Lab of Disaster Forecast and Control in Engineering College of Mechanics and Construction EngineeringJinan UniversityGuangzhou510632China State Key Laboratory of Fluid Power and Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceDepartment of Engineering MechanicsZhejiang UniversityHangzhou310027China

Tough elastomers and gels have garnered broad research interest due to their wide-ranging potential ***,during the loading and unloading cycles,a clear stress softening behavior can be observed in many material systems,which is also named as the Mullins *** this work,we aim to provide a complete review of the Mullins effect in soft yet tough materials,specifically focusing on nanocomposite gels,double-network hydrogels,and multi-network *** first revisit the experimental observations for these soft *** then discuss the recent developments of constitutive models,emphasizing novel developments in the damage mechanisms or network *** phenomenological models will also be briefly *** attention is then placed on the anisotropic and multiaxial modeling *** is demonstrated that most of the existing models fail to accurately predict the multiaxial data,posing a significant challenge for developing future anisotropic models tailored for tough gels and elastomers.

关键词： Mullins effect Double-network hydrogels Nanocomposite gels Multi-network elastomers Anisotropic damage model Multiaxial model

Delivery of surface-mediated non-viral gene nanoparticles from ultrathin layer-by-layer multilayers

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Science china Chemistry 2010年第3期53卷 508-513页

作者： WANG XueFei,REN KeFeng,lin QuanKui & JI Jian Key Laboratory of Macromolecule Synthesis and Functionalization,Ministry of Education Department of Polymer Science and Engineering,zhejiang university,hangzhou 310027,china Key Laboratory of Macromolecule Synthesis and Functionalization Ministry of Education Department of Polymer Science and Engineering Zhejiang University Hangzhou China

An efficient and safe gene delivery system remains a challenge in the development of gene ***-based gene nanoparticles are a typical non-viral gene delivery system,which are able to transfect cells in vitro and in *** paper reported a facile method for constructing biodegradable multilayers via layer-by-layer self-assembly,in which the polycation-based gene nanoparticles were *** this surface-mediated delivery system,adherent cells on the multilayer could be transfected in *** nanoparticles-loaded multilayers transfect cells with higher efficiency than naked DNA-loaded multilayers because of the complex configuration of the *** nanoparticles/PGA multilayers constructed on the scaffold surface could also realize in situ transfection on the adherent *** well-structured,easy-processed multilayers may provide a novel approach to precisely controlled delivery of gene nanoparticles,which may have potential applications for gene therapy in tissue engineering and medical implants.

关键词： DNA nanoparticles layer-by-layer self-assembly biodegradability in situ transfection poly(lactic acid) scaffold

Determination of gemcitabine and its metabolite in human plasma using high-pressure liquid chromatography coupled with a diode array detector

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Acta Pharmacologica Sinica 2004年第12期25卷 18-23页

作者： Neng-ming lin2,3, Su ZENG2,4, Sheng-lin MA3, Yun FAN3, Hai-jun ZHONG3, Luo FANG3 2Collegeof Pharmaceutical Sciences, zhejiang university, hangzhou 310031 3zhejiang Cancer Hospital, hangzhou 310022, china College of Pharmaceutical Sciences Zhejiang University Hangzhou 310031 zhejiang Cancer Hospital Hangzhou 310022

AIM: To establish a high pressure liquid chromatography (HPLC) method for determination of the concentration of gemcitabine (dFdC) and its metabolite(dFdU) in human plasma. METHODS: Plasma 1.0 mL spikedwith floxuridine as an internal standard was extracted with 3.0 mL of methanol-acetonitrile (v/v, 1:9). The supernatant was evapo- rated at 60 oC and the residue was reconstituted with 0.5 mL of the solution used as the mobile phase. After centrifugation, 50 μL of the supernatant was injected into the HPLC system. Separation was achieved on a C18 (4.6 mm×250 mm, 5 μm) column at 25 oC with the flow rate of the mobile phase set to 0.8 mL/min. The compounds were detected at 268 nm. The mobile phase consisted of 40.0 mmol/L acetate ammonium buffer solution (pH 5.5) and acetonitrile (v/v, 97.5:2.5). RESULTS: The linear range was 0.20-10.0 mg/L(r=0.9999) for dFdC and 0.50-50.0 mg/L(r=0.9999) for dFdU. The limit of detection (LOD) was 0.10 mg/L for dFdC and 0.25 mg/L for dFdU, while the limit of quantification (LOQ) was 0.20 mg/L (RSD<10 %) for dFdC and 0.50 mg/L(RSD <3 %) for dFdU. The average recovery of dFdC and dFdU by this method were 103.3 % and 98.7 %, respectively. For intra-day and inter-day, the corresponding standard deviations of the measurements of dFdC and dFdU were both less than 5.5 %. CONCLUSION: An analytical method was established to measure the concentrations of dFdC and dFdU in human plasma and was effectively applied to the dFdC and dFdU pharmacokinetic studies of 8 Chinese patients with malignant tumors.

关键词： high pressure liquid chromatography gemcitabine deoxycytidine floxuridine

FIBER ORIENTATION DISTRIBUTIONS IN SLIT CHANNEL FLOWS WITH ABRUPT EXPANSION FOR FIBER SUSPENSIONS

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Journal of Hydrodynamics 2008年第6期20卷 696-705页

作者： KU Xiao-ke lin Jian-zhong State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China china Jiliang university Hangzhou 310018 China

The lattice Boltzmann method was used to investigate numerically the fiber orientation distributions in slit channel flows with abrupt expansion for fiber suspensions even in the concentrated regime. The channels have a thin slit geometry with 1：4 and 1：3 expansions. Both the interactions between fibers and that between fibers and channel walls were taken into consideration. Some of numerical results are qualitatively in agreement with the experiment data. It is found that most of fibers are aligned in the flow direction in all the suspensions in the entrance region of the expansion. Fiber orientation distributions, having different patterns in different regions of the flow, depend on the expansion ratio of the channel. The mechanical fiber-fiber interaction largely affects the fiber orientation in the downstream of the expansion and in the salient corner for the cases of concentrated suspensions. The hydrodynamic interaction plays an important role on the fiber orientation in the dilute suspension.

关键词： fiber suspension orientation distributions lattice Boltzmann method slit channel flows with abrupt expansion