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Green long-after-glow luminescence of Tb^(3+)in Sr_2SiO_4

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Chinese Physics B 2014年第6期23卷 266-270页

作者：王齐邱建备宋志国周大成徐旭辉 College of materials Science and Engineering Kunming University of Science and Technology Research center for analysis and Measurement Kunming University of Science and Technology

The green long-after-glow luminescence from Tb3＋-doped Sr2SiO4 phosphors, which are synthesized by the high temperature solid state reaction in a reductive atmosphere, is observed in this paper. The results show that under ultraviolet excitation, the obtained phosphors produce an intense green-lighting-emission from the Tb3＋, and the green-lighting long- after-glow luminescence related to Tb3＋ can last half an hour after the irradiation source has been removed. Moreover, the effects of co-doping Li＋, Dy3＋, Er3＋, Gd3＋, and Yb3＋ with Tb3＋ on the decay properties and thermoluminescence properties are investigated to confirm the long-after-glow mechanism.

关键词： long-after-glow luminescence Tb3+ Sr2SiO4

Self-healing anti-icing coatings prepared from PDMS polyurea

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Science China(Technological Sciences) 2021年第7期64卷 1535-1543页

作者： ZHAO XueWei PENG Jie GAO ShuHui ZHU KongYing ZHAO YunHui LI XiaoHui YUAN XiaoYan School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350China analysis and Measurement center Tianjin UniversityTianjin300072China

With the help of double hydrogen bonds between urea groups, a self-healing anti-icing coating was prepared from polydimethylsiloxane(PDMS)-based polyurea(PDMSPU) that was synthesized from bis(3-aminopropyl)-terminated PDMS and2,4-toluene diisocyanate. Furthermore, by incorporating a lubricant of inert silicone oil and the cross-linking agent of 1,3,5-tris-(4-aminophenoxy)benzene(TAPOB), the anti-icing coatings exhibited elastic, slippery and durable properties. The wettability,ice shear strength, abrasion-resistance, mechanical and self-healing properties of the prepared anti-icing coatings were systematically investigated. Results showed that the ice shear strength of the PDMSPU anti-icing coating with 150 wt% silicone oil was 7.9±2.9 kPa, significantly lower than that of pristine PDMSPU(74.7±7.2 kPa). The additional introduction of 2 wt%TAPOB could effectively counteract the adverse effect of the lubricant so that the tensile strength(~1 MPa) of the coating could be comparable to pristine PDMSPU(855±96 kPa). The PDMSPU coating containing 150 wt% silicone oil and 2 wt% TAPOB could maintain the ice shear strength below 50 kPa against 10 icing/deicing cycles and at 12.0±3.3 kPa after 5000 abrasion cycles, and exhibit self-healing properties after treating at 60°C for 10 or 15 h. The slippery self-healing PDMSPU anti-icing coatings could be suitable for anti-icing surfaces in low temperature environments.

关键词： polydimethylsiloxane polyurea coatings anti-icing self-healing

Melittin enhanced intracellular trehalose with synergistic membrane stabilization of macromolecular protectants for cell cryopreservation

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Science China(Technological Sciences) 2024年第4期67卷 1160-1169页

作者： NIU QingJing GAO ShuHui ZHU KongYing REN LiXia YUAN XiaoYan School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China analysis and Measurement center Tianjin UniversityTianjin 300072China

Cryopreservation plays an essential role in biobanking and cell therapy,but the physiological toxicity of traditional cryoprotectants such as glycerol and dimethyl sulfoxide(DMSO)has raised safety issues for biomedical ***,a nonreducing disaccharide that accumulates in desiccation-or cold-tolerant organisms,has been considered as a biocompatible ***,a naturally occurring membrane-active cationic peptide,melittin,was utilized to facilitate membraneimpermeable trehalose entry into cells for effective cell ***(ethylene glycol)and poly(vinyl pyrrolidone)were applied as macromolecular protectants to improve the stabilization of cell *** the optimal protocol,the postthaw recovery of human red blood cells in freezing bags at a hematocrit of~50%could achieve 82.9%with favorable cell morphologies and physiological ***,the cryosurvival of L929 fibroblasts reached 84.3%compared to the conventional method using 10%(v/v)*** short,this work by using trehalose and melittin provides a biocompatible solvent-free approach for long-term cryostorage of cells.

关键词： melittin intracellular trehalose membrane stabilization macromolecular protectants cell cryopreservation

A systematic review of progenitor survival and maturation in Parkinsonian models

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Neural Regeneration Research 2025年第11期20卷 3172-3178页

作者： Giulia Comini Eilís Dowd Pharmacology&Therapeutics and Galway Neuroscience center University of GalwayGalwayIreland

Stem cell-based brain repair is a promising emergent therapy for Parkinson's disease based on years of foundational research using human fetal donors as a cell *** current therapeutic options for patients,this approach has the potential to provide longterm stem cell–derived reconstruction and restoration of the dopaminergic input to denervated regions of the brain allowing for restoration of certain functions to *** ultimate clinical success of stem cell–derived brain repair will depend on both the safety and efficacy of the approach and the latter is dependent on the ability of the transplanted cells to survive and differentiate into functional dopaminergic neurons in the Parkinsonian *** the pre-clinical literature suggests that there is considerable variability in survival and differentiation between studies,the aim of this systematic review was to assess these parameters in human stem cell-derived dopaminergic progenitor transplant studies in animal models of Parkinson's disease.A defined systematic search of the PubMed database was completed to identify relevant studies published up to March *** screening,76 articles were included in the analysis from which 178 separate transplant studies were *** these,graft survival could be assessed in 52 studies and differentiation in 129 ***,we found that graft survival ranged from<1% to 500% of cells transplanted,with a median of 51%of transplanted cells surviving in the brain;while dopaminergic differentiation of the cells ranged from 0% to 46% of cells transplanted with a median of 3%.This systematic review suggests that there is considerable scope for improvement in the differentiation of stem cell-derived dopaminergic progenitors to maximize the therapeutic potential of this approach for patients.

关键词： cell replacement therapy differentiation embryonic stem cells graft induced pluripotent stem cells Parkinson's disease survival transplant

Synthesis and Crystal Structure of Diethyl-2,6-dimethyl-3,5-diyl-(1-(2-chlorobenzoyl)-1H- pyrazole-3-diethyl-carboxylate)-pyridine

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Chinese Journal of Structural Chemistry 2008年第10期27卷 1163-1166页

作者：钱群张敏李志芬曹卫国张军邵敏夏义本 Department of Chemistry Shanghai University Instrumental analysis and Research center Shanghai University School of materials Science and Engineering Shanghai University

The reaction of hydrazine hydrate with a new α,γ-diketone ester 3, derived from the reaction of 2,6-dimethyl-3,5-diacetyl-pyridine 2 with diethyl oxalate in the presence of sodium ethoxide, afforded the pyrazole derivative 4. Treatment of 4 with 2-chlorobenzoyl chloride gave diethyl 2,6-dimethyl-3,5-diyl-（1-2（chlorobenzoyl）-1H-pyrazole-3-diethyl-carboxylate） pyridine 5. Fine crystal of 5 suitable for XRD analysis was obtained form recrystalization in ethyl acetate. The crystal belongs to the triclinic system, space group P1^-, with a = 1.0342（11）, b = 1.2211（12）, c = 1.5013（15） nm, α = 82.5190（10）,β = 85.7960（10）,γ = 85.3150（10）°, V= 1.8697（3） nm^3, Dc= 1.173 g/cm^3, μ = 0.219 mm^-1, F（000） = 684, Z = 2, the final R = 0.0720 and wR = 0.2211.

关键词： pyridine pyrazole N-acylation crystal structure

Phonon Characterization of Raman Spectra in High T_(c) Superconductors Y_(1-x)Gd_(x)Ba_(2)Cu_(3)O_(7-δ)

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Chinese Physics Letters 1994年第1期11卷 31-34页

作者： ZHANG Mingsheng CHEN Qiang JIN Xin YIN Zhen YAO Xixian center for materials analysis National Laboratory of Solid State Microstructures Department of Physics Nanjing UniversityNanjing 210008

Concentration-dependent Raman spectra of Y_(1-x)Gd_(x)Ba_(2)Cu_(3)O_(7-δ)(x=0.4,0.6,0.8 and 1.0)show that the Raman mode from O(4)bridging shifts upward due to the increased symmetry of crystal *** linewidth and intensity of 508cm^(-1)mode are decreased and increased with increasing x,respectively which is attributed to the charge transfer from the CuO basal planes to the CuO_(2)*** second-order Raman modes at 798 and 896cm^(-1)have been observed and confirmed.

关键词： mode Superconductor

Base-Promoted Synthesis of 3-Alkenyl-2-pyridones from N-Propargyl-β-enaminones and Aryl Aldehydes

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Chinese Journal of Chemistry 2021年第10期39卷 2781-2788页

作者： Qingyu Tian Shangyun Xiao Guolin Cheng Xiamen Key Laboratory of Optoelectronic materials and Advanced Manufacturing College of Materials Science and EngineeringInstrumental Analysis CenterHuaqiao UniversityXiamenFujian361021 China

Main observation and conclusion In this article,we report a base-promoted sequential cyclization/aldol-type condensation/isomerization cascade reaction of N-propargyl-β-enaminones with aryl *** key step in this protocol is the generation of 1,4-oxazepine anions from N-propargyl-β-enaminones under basic conditions,which are captured by aryl *** method allows the formation of one pyridone core and one C—C double bond in“one pot”,and the preparation of a variety of densely decorated pyridone derivatives in moderate to good yields with broad functional group tolerance.

关键词： Domino reactions Aldehydes Alkenes Enaminone Pyridones

Enhanced anti-icing properties of branched PDMS coatings with self-regulated surface patterns

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Science China(Technological Sciences) 2020年第6期63卷 960-970页

作者： PENG Jie LIU Bo GAO ShuHui ZHU KongYing ZHAO YunHui LI Xiao Hui YUAN XiaoYan School of materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China analysis and Measurement center Tianjin UniversityTianjin 300072China

Adverse impact of icing,on either infrastructures or facilities,is the great impulsion for seeking anti-icing coatings with high *** this work,durable icephobic coatings with self-regulated surface patterns were developed from branched polydimethylsiloxane(PDMS)co-crosslinked with fluorinated polyhedral oligomeric silsesquioxane(POSS)through a breath figure *** prepared coatings with patterned microstructures on the surfaces exhibited excellent anti-icing performance ascribed to micro-crack generation between ice and coating surface under a small external *** stable cross-linked network composed of branched PDMS and fluorinated POSS endowed the coatings with durability and abrasion *** ice shear strength was achieved at approximate 19.7±2.5 kPa on coating surface with self-regulated honeycomb *** experiencing 30 icing/deicing cycles,the ice shear strength of the coating varied ***,owing to dedication of fluorinated POSS,the coating showed merely a little increase in ice shear strength after more than 1600 abrasion cycles,which was still in the icephobic range below 50 ***,the prepared coatings with remarkably enhanced anti-icing performance and superior mechanical stability would be promising for the practical applications.

关键词： branched PDMS fluorinated POSS patterned surfaces icephobic coatings durability

analysis of crack opening stresses for center- and edge-crack tension specimens

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Chinese Journal of Aeronautics 2014年第2期27卷 291-298页

作者： Tong Di-Hua Wu Xue-Ren AVIC Beijing Institute of Aeronautical materials

Accurate determination of crack opening stress is of central importance to fatigue crack growth analysis and life prediction based on the crack-closure model. This paper studies the crack opening behavior for center- and edge-crack tension specimens. It is found that the crack opening stress is affected by the crack tip element. By taking the crack tip element into account, a modified crack opening stress equation is given for the center-crack tension specimen. Crack surface displace- ment equations for an edge crack in a semi-infinite plate under remote uniform tension and partially distributed pressure are derived by using the weight function method. Based on these displacements, a crack opening stress equation for an edge crack in a semi-infinite plate under uniform tension has been developed. The study shows that the crack opening stress is geometry-dependent, and the weight function method provides an effective and reliable tool to deal with such geometry depen- dence.

关键词： center- and edge-crack Crack closure Crack opening stresses Crack surface displacements Weight function method