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Luminescent nanoparticle-arrays synthesized via polymer pen lithography

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Nano Research 2023年第2期16卷 3125-3129页

作者： Ping Wang Shuyi Bao Shuqian Qiao ce Li Zhang Jiang Hao Song Yilin Wang Qiuqiang Zhan Ling Huang Institute of Advanced Materials Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing Tech UniversityNanjing 211816China centre for Optical and electromagnetic Research Guangdong Provincial Key Laboratory of Optical Information Materials and TechnologyNational Centre for International Research on Green OptoelectronicsSouth China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China College of Chemistry State Key Laboratory of the Chemistry and Utilization of Carbon Based EnergiesXinjiang UniversityUrumqi 830046China

We report a high-throughput approach to generating lanthanide-doped upconversion nanoparticle(UCNP)arrays through polymer pen lithography(PPL),where instead of the expensive block co-polymer,two types of polymers are employed with one working as ink carrier,e.g.,polyethylene glycol-400(PeG-400)to facilitate smooth transfer from the tip to the substrate and the other,e.g.,polyvinyl pyrrolidone(PVP),as chelator to ensure successful patterning of metal *** strong coordination of PVP with rare earth ions(Re^(3+))is the key for weakening the interaction between Re3+ions and the carrier PeG-400 so that the good mobility of ink can be *** experimental results have shown that besides PVP,small molecules with functional groups that can coordinate with Re^(3+)ions,such as oleic acid,can also serve the same role as PVP,which greatly enriches the ink library for *** 1 cm^(2)area arrays comprising individual UCNP can be reliably generated with characteristic upconversion *** strategy not only allows reliable production of individual UCNP arrays,it also paves new avenue to the precise synthesis of multifunctional NPs for lasing,imaging,encryption,and anticounterfeiting.

关键词： polymer pen lithography upconversion luminescence nanoparticle array ligand

Stability of Time-Dependent Diffusion Semigroups and Kernels

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Acta Mathematica Sinica,english Series 1999年第4期15卷 575-586页

作者： Weian ZhengDepartment of Mathematics,University of california,Irvine,ca92612,U S ADepartment of Statistics,east China Normal University,Shanghai 200062,P.R.China e-mail:wzhengmath.uci.edu Department of Mathematics University of California Irvine USA Department of Statistics East China Normal University Shanghai P. R. China

The main result of this paper is that when the coefficients of the time-dependent divergence form operators are Hlder continuous in time with order not too much smaller than （1/2）,the distance of the semigroups of t... 详细信息

关键词： Time-dependent diffusion semigroups Stability Hlder continuous

High electrocaloric cooling power of relaxor ferroelectric BaZr_xTi_(1–x)O_3 ceramics within broad temperature range

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Science Bulletin 2018年第6期63卷 356-361页

作者： Jianfeng Qian Penghao Hu Chen Liu Jianyong Jiang Zhenkang Dan Jing Ma Yuanhua Lin ce-Wen Nan Yang Shen School of Materials Science and engineering and State Key Laboratory of New Ceramics and Fine Processing Tsinghua University Institute for Advanced Materials and Technology University of Science & Technology Beijing

electrocaloric effect （ece） is much promising to realize high efficiency and environment friendly solution in solid cooling devices. Relaxor ferroelectrics are good candidates for the materials with high elec-trocaloric cooling power. In this paper, relaxor ferroelectric Ba（ZrxTil_x）O3 （BZT, x = 0.2, 0.21, 0.22, 0.23） ceramics were prepared with their temperature change （AT） induced by the ece and electrocaloric strength （AT/e） measured within broad temperature range. It is found that the BZT21 （x = 0.21) exhibits the largest ATof-4.67 K and a high AT/e value of-0.46 km/MV at 9.9 MV/m and 25℃. BZT21 also exhi-bits apparent relaxor ferroelectric response, showing a very broad eC peak in the temperature interval between 15℃ and 50℃. Moreover, the relationship between eC properties and relaxor features was analyzed by piezoresponse force microscopy test. The results reveal that more dispersed phase structures induce additional configurational entropy, which is in favor for the enhanced eC performance. The inter-play and compromise between the kinetic and thermodynamic mechanisms of domain switching deter-mines the optimal composition for the eC performances of the BZT ceramics.

关键词： electrocaloric effectRelaxor ferroelectricsPiezoresponse force microscopy Domain structure

Hydroxyl-terminated Polyethylenes Bearing Functional Side Groups:Facile Synthesis and Their Properties

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Chinese Journal of Polymer Science 2021年第8期39卷 994-1003,I0006页

作者： Wan-Bin Zhang Jie Luo Yan-Meng Wang Xiu-Zhong Zhu ce Zhang Jing Liu Mei-Le Ni Guang-Hua Zhang Shaanxi Collaborative Innovation center of Industrial Auxiliary Chemistry and Technology Shaanxi University of Science&TechnologyXi'an 710021China Shaanxi Key Laboratory of Che.ical Additives for Industry College of Chemistry and Chemical EngineeringShaanxi University of Science&TechnologyXi'an 710021China School of Light Industry and engineering Qi Lu University of Technology(Shandong Academy of Sciences)Jinan 250353China

A series of hydroxyl-terminated polyethylenes(HTPe)bearing various functional side groups(***,ester and butane groups)were synthesized by the combination of ring opening metathesis polymerization(ROMP)and visible light photocatalytic thiol-ene *** products are named as a,w-dihydroxyl-polyllpropionyloxythio)methinetrimethylene](HTPecarboxy),a,w dihydroxy-poly(methylpropionatethio)methinetrimethylene](HTPeeser)and a,wdihydroxyl-poly[(butylthio)methinetrimethylene](HTPebutane)*** investigation of ROMP indicated that the molecular weight of resultant hydroxy-terminated polybutadiene(HTPB)can be tailored by varying the feed ratios of monomer to chain transfer agent(CTA).The exploration of the photocatalytic thiol-ene reaction between HTPB precursor and methyl-3-mercaptopropionate revealed that blue light as well as oxygen accelerated the reaction.1H-NMR and 13C-NMR results verified all the double bonds in HTPB can be modified,and the main chain of resultant polymer can be considered as ***,relationship between the structure of side groups and the thermal properties of functional Pes was *** the results suggested that the Tg was in the order of HTPebuaneeesterearboxy+.Greater interaction between side groups resulted in higher ***,all the functional Pe samples exhibited poor thermostability as compared to ***,the promising applications for functional Pes were ***1 can be utilized as a smart material with pH-responsive properties due to its pH-dependent ionization of carboxyl side *** can be employed as a macro-initiator for building the triblock copolymer due to the presence of active hydroxyl end *** can serve as a plasticizer for PVC which can enhance the ductilityt of PVC without obviously sacrificing strength.

关键词： Polyethylene Ring-opening metathesis polymerization Thiol-ene reaction Polybutadiene Structure property relationships

Molten salt as ultrastrong polar solvent enables the most straightforward pyrolysis towards highly efficient and stable single-atom electrocatalyst

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Journal of energy Chemistry 2021年第3期30卷 519-527页

作者： Nannan Li Wei Liu Chao Zhu ce Hao Jingya Guo Hongyu Jing Jinwen Hu Cuncun Xin Danyang Wu Yantao Shi State Key Laboratory of Fine Che.icals Department of ChemistrySchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina SeU-FeI Nano-Pico center Key Laboratory of MEMS of Ministry of EducationCollaborative Innovation Center for Micro/Nano FabricationDevice and SystemSoutheast University2 No.4 PailouNanjing 210096JiangsuChina

Currently,pyrolysis as the most widely used method still has some key issues not well resolved for synthesis of carbon-supported single-atom catalysts(C-SACs),e.g.,the sintering of metal atoms at high temperature as well as the high cost and complicated preparations of *** this report,molten salts are demonstrated to be marvellous medium for preparation of C-SACs by pyrolysis of small molecular precursors(ionic liquid).The ultrastrong polarity on one hand establishes robust interaction with precursor and enables better carbonization,resulting in largely enhanced *** the other hand,the aggregation of metal atoms is effectively refrained while no nanoparticle or cluster is *** this strategy,a C-SAC with atomically dispersed Fe-N_(4) sites and a high specific area over 2000 m^(2) g^(-1) is obtained,which illustrates high ORR activity in both acid and alkaline ***,this SAC exhibits superior methanol tolerance and stability after acid soaking at 85℃ for 48 *** is believed that the molten-salts-assisted pyrolysis can be developed into a routine strategy as it not only can largely simply the synthesis of C-SACs,but also can be extended to prepare other types of SACs.

关键词： Ultrastrong polar solvent Molten salts one-pot pyrolysis carbon-supported single atom catalysts Oxygen reduction reaction

Gallic Acid/2-Hydroxypropyl-β-cyclodextrin Inclusion Complexes electrospun Nanofibrous Webs:Fast Dissolution,Improved Aqueous Solubility and Antioxidant Property of Gallic Acid

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Che.ical Research in Chinese Universities 2021年第3期37卷 450-455页

作者： SONG Yudong HUANG Hui He Dayong YANG Mei WANG Hao ZHANG Hao LI Jiali LI Yongxin WANG ce College of Food Science and engineering Jilin UniversityChangchun130025P.R.China Key Lab of Groundwater Resources and environment of Ministry of education College of New Energy and EnvironmentJilin UniversityChangchun130021P.R.China Alan G.MacDiarmid Institute College of ChemistryJilin UniversityChangchun130012P.R.China

Gallic acid(GA)is a kind of natural polyphenolic compound,but its low aqueous solubility restricts its application in the fields of food and *** can form inclusion complexes with guest molecules(e.g.,essential oils,food supplements)through cavities with special properties to improve aqueous solubility,thermal stability,and bioavailability of guest *** this research,gallic acid/2-hydroxypropyl-β-cyclodextrin inclusion complexes(GA/2-HP-β-CD/ICs)were formed in a highly concentrated solution of 2-HP-β-***-free and uniform nanofibrous webs(GA/2-HP-β-CD/IC-NWs)were produced successfully by electrospun GA/HP-β-CD/IC aqueous *** initial molar ratio(GA:2-HP-β-CD=1:1)of GA/2-HP-β-CD/IC in the solutions was largely maintained in GA/2-HP-β-CD/*** aqueous solubility of GA was enhanced and GA/2-HP-β-CD/IC-NW has displayed fast dissolution ***,in comparison with GA powder,GA/2-HP-β-CD/IC-NW demonstrated improved antioxidant *** results suggested that GA/2-HP-β-CD/IC-NW have broad application prospects as orally fast dissolution systems for food supplements.

关键词： Gallic acid 2-Hydroxypropyl-β-cyclodextrin Inclusion complex electrospun Fast dissolution

Shear strength behavior of geotextile/geomembrane interfaces

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Journal of Rock Mechanics and Geotechnical engineering 2015年第6期7卷 638-645页

作者： Belén M.Bacas Jorge caizal Heinz Konietzky Terrasolum S.L.Geotechnical engineering Technology Development Center of University of Cantabria(CDTUC) School of Civil engineering University of Cantabria Geotechnical Institute TU Bergakademie Freiberg

This paper aims to study the shear interaction mechanism of one of the critical geosynthetic interfaces,the geotextile/geomembrane, typically used for lined containment facilities such as landfills. A largedirect shear machine is used to carry out 90 geosynthetic interface tests. The test results show a strainsoftening behavior with a very small dilatancy （〈0.5 mm） and nonlinear failure envelopes at a normalstress range of 25e450 kPa. The influences of the micro-level structure of these geosynthetics on themacro-level interface shear behavior are discussed in detail. This study has generated several practicalrecommendations to help professionals to choose what materials are more adequate. From the threegeotextiles tested, the thermally bonded monofilament exhibits the best interface shear strength underhigh normal stress. For low normal stress, however, needle-punched monofilaments are *** the regular textured geomembranes tested, the space between the asperities is an important *** closer these asperities are, the better the result achieves. For the irregular textured geomembranestested, the nonwoven geotextiles made of monofilaments produce the largest interface shear strength.

关键词： Geotextiles Geomembranes Landfills Fiber length Roughness Shear strength Friction angle

Ordered coalescence of nano-crystals in alkaline niobate ceramics with high remanent polarization

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Journal of Materiomics 2017年第4期3卷 267-272页

作者： Zhijian Shen Daniel Gruner Mirva eriksson Lyubov M.Belova ce-Wen Nan Haixue Yan Department of Materials and environmental Chemistry Arrhenius LaboratoryStockholm University10691StockholmSweden Department of Materials Science and engineering Royal Institute of Technology10044StockholmSweden School of Materials Science and engineering Tsinghua UniversityBeijing100084China School of engineering and Materials Science Queen Mary University of LondonMile End RoadLondonE14NSUK

Lead-free alkali niobates Na_(0.5)K_(0.5)NbO_(3)(NKN)ceramics,with significantly enhanced ferroelectric remanent polarization(Pr),were prepared using Spark Plasma Sintering(SPS).Three types of boundaries were observed in the ceramics,being grain boundaries between faceted grains,domain boundaries that separate ferroelectric domains inside individual grains,and nanoscale sub-grain boundaries that reveal the nano-scale mosaicity of individual *** of the sub-grain boundaries were from initial powder *** other sub-grain boundaries were built by ordered coalescence of nano-crystals during rapid SPS *** was worthwhile to emphasize that the ordered coalescence of nano-crystals in bulk ceramics during sintering takes place and completes within *** sub-grain features would disappear at higher temperature by long time *** Spark Plasma Sintering allowed us to capture this transient *** significantly enhanced ferroelectric Pr of NKN was attributed to nanoscale sub-boundaries,which stimulated the dynamics of ferroelectric domain formation and switching.

关键词： Lead-free NKN SPS Remanent polarization Ordered coalescence

Induction of IgA and sustained deficiency of cell proliferative response in chronic hepatitis C

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World Journal of Gastroenterology 2008年第44期14卷 6844-6852页

作者： Yalena Amador-caizares Liz Alvarez-Lajonchere Ivis Guerra Ingrid Rodríguez-Alonso Gillian Martínez-Donato Julián Triana eddy e González-Horta Angel Pérez Santiago Dueas-carrera centro de Ingeniería Genética y Biotecnología Ave 31e/ 158 and 190PlayaP.O. Box 6162HavanaCuba

AIM： In the present study, antibody and peripheral blood mononuclear cells （PBMC） proliferative responses against hepatitis C virus （HCV） antigens were evaluated in HCV chronically infected patients. MeTHODS： Paired serum and PBMC samples were taken six months apart from 34 individuals, either treated or not, and tested by enzyme-linked immunosorbent assay （eLISA） and carboxyfluorescein succinimidyl ester staining. RSULTS： Over 70% of the patients showed specific IgG and IgM against capsid, e1 and NS3, while HVR-1 was recognized by half of the patients. An increase in the levels of the anti-capsid IgM （P = 0.027） and IgG （P = 0.0006） was observed in six-month samples, compared to baseline. Similarly, a significantly higher percent of patients had detectable IgA reactivity to capsid （P = 0.017） and NS3 （P = 0.005） after six months, compared to baseline. Particularly, IgA against structural antigens positively correlated with hepatic damage （P = 0.036）. IgG subclasses evaluation against capsid and NS3 revealed a positive recognition mediated by IgG1 in more than 80% of the individuals. On the contrary, less than 30% of the patients showed a positive proliferative response either of CD4＋ or CD8＋ T cells, being the capsid poorly recognized. CONCLUSION： These results confirm that while the cellular immune response is narrow and weak, a broad and vigorous humoral response occurs in HCV chronic infection. The observed correlation between IgA and hepatic damage may have diagnostic significance, although it warrants further confirmation.

关键词： Hepatitis C Antibody response Lymphoproliferation Core envelope