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Tuning the Johari-Goldstein β-Relaxation and Its Separation from α-Relaxation of Poly(n-alkyl methacrylate)s by Small Molecule-bridged Hydrogen Bonds

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Chinese Journal of Polymer Science 2021年第11期39卷 1459-1469页

作者： Yuan-biao liu Gao-Peng Shi Guo-Zhang Wu Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science&EngineeringEast China University of Science&TechnologyShanghai 200237China

Introducing small molecule-bridged hydrogen bonds(HBs)between polymer chains has been reported to effectively reduce the interchain cooperativity despite of strengthening the intermolecular ***,a systematic investigation on tuning the Johari-Goldsteinβ(βJG)relaxation by adding various low-molecular-weight phenols in poly(n-alkyl methacrylate)s is carried out to further clarify the anomalous *** these small molecules capable of coupling the motion with pendent groups of host polymers due to forming at least two HBs per molecule,poly(n-alkyl methacrylate)mixtures exhibit rich dynamic changes in theβJG-properties andα,βJG *** increased loading of phenols with a small size and strong inter-HB strength(Δυi)clearly benefits for significant retardation and suppression of theβJG-relaxation,narrows theα,βJG separation and converges theβJG-peak with theα-peak,which demonstrates the alleviation of inter-chain topological ***,small molecules with a relatively big size and weakΔυi are found to amplify the magnitude of theα,βJG separation of poly(butyl methacrylate),even though experimental results of changes inα-dispersion and dynamic fragility confirm a reduction of the coupling factor n in all of these *** counterintuitive phenomenon suggests that the crossover time tc in the Coupling Model is no longer a universal quantity if the inter-chain interaction of polymers is strengthened by *** compelling findings shed vital insights into the HBinduced anomalous dynamics,and provide essential guidance for tailoring theβJG behavior and designing glassy polymeric materials.

关键词： Johari-Goldsteinβ-relaxation Hydrogen bond Glass transition Poly(n-alkyl methacrylate) Small molecule

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Persistently Upregulated Hippocampal mTOR Signals Mediated by Fecal SCFAs Impair Memory in Male Pups with SMM Exposure in Utero

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Biomedical and Environmental Sciences 2019年第5期32卷 345-356页

作者： ZHU Yi Tian liu Xin Ji liu Kai Yong ZHANG Qiang YANG Lin sheng WEI Rong ZHANG Jing Jing TAO Fang biao Department of Nutrition and Food Hygiene School of Public HealthAnhui Medical UniversityHefei 230032AnhuiChina Anhui Provincial Key Laboratory of Population Health and Aristogenics Hefei 230032AnhuiChina Hefei Municipal Center for Disease Control and Prevention Hefei 230000AnhuiChina Department of Epidemiology and Biostatistics School of Public HealthAnhui Medical UniversityHefei 230032AnhuiChina

Objective To investigate the molecular mechanisms of the adverse effects of exposure to sulfamonomethoxin(SMM) in pregnancy on the neurobehavioral development of male offspring. Methods Pregnant mice were randomly divided into four groups: control‐(normal saline), low‐[10 mg/(***)], middle‐[50 mg/(***)], and high‐dose [200 mg/(***)] groups, which received SMM by gavage daily during gestational days 1‐18. We measured the levels of short‐chain fatty acids(SCFAs) in feces from dams and male pups. Furthermore, we analyzed the mR NA and protein levels of genes involved in the mammalian target of rapamycin(m TOR) pathway in the hippocampus of male pups by RT‐PCR or Western blotting. Results Fecal SCFA concentrations were significantly decreased in dams. Moreover, the production of individual fecal SCFAs was unbalanced, with a tendency for an increased level of total fecal SCFAs in male pups on postnatal day(PND) 22 and 56. Furthermore, the phosphatidylinositol 3‐kinase(PI3 k)/protein kinase B(AKT)/mTOR or mT OR/ribosomal protein S6 kinase 1(S6 K1)/4 EBP1 signaling pathway was continuously upregulated until PND 56 in male offspring. In addition, the expression of Sepiapterin Reductase(SPR), a potential target of m TOR, was inhibited. Conclusion In utero exposure to SMM, persistent upregulation of the hippocampal mTOR pathway related to dysfunction of the gut(SCFA)‐brain axis may contribute to cognitive deficits in male offspring.

关键词： Cognitive deficits Sulfamonomethoxine Short-chain fatty acids Mammalian target of rapamycin Sepiapterin reductase

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PdSe_(2)/MoSe_(2) vertical heterojunction for self-powered photodetector with high performance

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Nano Research 2022年第3期15卷 2489-2496页

作者： Jiahong Zhong biao Wu Yassine MADOUNE Yunpeng Wang Zongwen liu Yanping liu School of Physics and Electronics Hunan Key Laboratory for Super-microstructure and Ultrafast ProcessCentral South UniversityChangsha 410083China State Key Laboratory of High-Performance Complex Manufacturing Central South UniversityChangsha 410083China School of Chemical and Biomolecular Engineering The University of SydneyNSW 2006Australia The University of Sydney Nano Institute The University of SydneyNSW 2006Australia Shenzhen Research Institute of Central South University A510aVirtual University BuildingSouthern DistrictHigh-tech Industrial ParkYuehai StreetNanshan DistrictShenzhen 518057China

Van der Waals’two-dimensional(2D)material heterostructure engineering offers an effective strategy for the design of multifunctional and high-performance optoelectronic ***,2D heterostructure photodetectors with a photoconductive effect tend to suffer from high driving source-drain voltages and significant dark noise ***,a self-powered photodetector with high performance was fabricated based on vertically stacked graphene/MoSe_(2)/PdSe_(2)/graphene heterojunctions through a dry transfer *** fabricated device displays current rectification characteristics in darkness(on/off ratio>10^(3))and superior photovoltaic behaviors under *** addition,benefitting from the strong built-in field,the Gr/PdSe_(2)/MoSe_(2)/Gr heterojunction photodetector is able to respond to a broad spectrum from visible to near-infrared(NIR)with a remarkable responsivity of 651 mA·W^(−1),a high specific detectivity of 5.29×10^(11) Jones and a fast response speed of 41.7/62.5μ***,an enhanced responsivity of 1.16 A·W^(−1) has been obtained by a reverse voltage(−1 V)and further evaluation on image recognition has also demonstrated the great application potential of the Gr/MoSe_(2)/PdSe_(2)/Gr heterojunction *** findings are expected to bring new opportunities for the development of highly sensitive,high-speed and energy-efficient photodetectors for comprehensive applications.

关键词： heterostructure MoSe_(2) PdSe_(2) self-powered photodetector high performance

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Observation of interlayer excitons in trilayer type-Ⅱ transition metal dichalcogenide heterostructures

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Nano Research 2022年第10期15卷 9588-9594页

作者： biao Wu Haihong Zheng Junnan Ding Yunpeng Wang Zongwen liu Yanping liu School of Physics and Electronics Hunan Key Laboratory for Super-microstructure and Ultrafast ProcessCentral South UniversityChangsha 410083China State Key Laboratory of High-Performance Complex Manufacturing Central South UniversityChangsha 410083China School of Chemical and Biomolecular Engineering The University of SydneyNSW 2006Australia Shenzhen Research Institute of Central South University Shenzhen 518057China

Vertically stacked transition metal dichalcogenide(TMD)heterostructures provide an opportunity to explore optoelectronic properties within the two-dimensional *** such structures,spatially indirect interlayer excitons(IXs)can be generated in adjacent layers because of strong Coulomb ***,due to the complexity of the multilayered heterostructure(HS),the capture and study of the IXs in trilayer type-Ⅱ HSs have so far remained ***,we present the observation of the IXs in trilayer type-Ⅱ staggered band alignment of MoS_(2)/MoSe_(2)/WSe_(2) van der Waals(vdW)HSs by photoluminescence(PL)*** central energy of IX is 1.33 eV,and the energy difference between the extracted double peaks is 23 *** confirmed the origin of IX through PL properties and calculations by the density functional theory,we also studied the dependence of the IX emission peak on laser power and ***,the polarization-resolved PL spectra of HS were also investigated,and the maximum polarizability of the emission peak of WSe_(2) reached 11.40%at 6 *** findings offer opportunities for the study of new physical properties of excitons in TMD HSs and therefore are valuable for exploring the potential applications of TMDs in optoelectronic devices.

关键词： transition metal dichalcogenides interlayer exciton type-II band alignment trilayer heterostructure

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Characterization of metal doped-titanium dioxide and behaviors on photocatalytic oxidation of nitrogen oxides

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Journal of Environmental Sciences 2007年第12期19卷 1505-1509页

作者： liu Yue WANG Hai-qiang WU Zhong-biao Department of Environmental Engineering Zhefiang University Hangzhou 310027 China.

A series of nanosized ion-doped TiO2 catalysts with different ion content （between 0.1 at.% and 1.0 at.%） have been prepared by wet impregnation method and investigated with respect to their behavior for UV photocatalytic oxidation of nitric oxide. The catalytic activity was correlated with structural, electronic and surface examinations of the catalysts using X-ray diffraction analysis （XRD）, ultraviolet-visible （UV-Vis） absorption spectroscopy, transmission electron microscopy （TEM）, energy disperse spectrometer （EDS） and high resolution-transmission electron microscopy （HR-TEM） techniques. An enhancement of the photocatalytic activity was observed for Zn2＋ doping catalyst ranged from 0.1 at.% to 1.0 at.% which was attributed to the lengthened lifetime of electrons and holes. The improvement in photocatalytic activity could be also observed with the low doping concentration of Cr^3＋（0.1 at.%）. However, the doping of Fe^3＋, Mo^6＋, Mn^2＋ and the high doping concentration of Cr^3＋ had no contribution to photocatalytic activity of nitric oxide.

关键词： NO photocatalytic oxidation ion doping doped

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Characteristics of microfauna and their relationships with the performance of an activated sludge plant in China

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Journal of Environmental Sciences 2008年第4期20卷 482-486页

作者： ZHOU Kexin XU Muqi liu biao CAO Hong Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China Nanjing Institute of Environmental Sciences State Environmental Protection Administration Nanjing 210042 China

The occurrence and abundance of the microfauna groups were compared with the physico-chemical and operational parameters of the Baoding Lugang Sewage Treatment Plant in China. Attached and crawling ciliates were the dominant groups of ciliates. Crawling ciliates and testate amoebae showed a strong association with effluent BOD5 （biochemical oxygen demand）. Therefore, these two groups are likely to be useful bioindicators since their number decreased as the process produced poor quality effluent. Testate amoebae also had significant negative correlations with effluent TN （total nitrogen）, NH4^＋-N, SS （suspended solids） and SVI （sludge volumetric index）, which means that this group of ciliates may be indicators of good performance of the activated sludge system. Carnivorous ciliates and flagellates had significant positive correlations with SVI, suggesting that these two groups may be indicators of bad settlement conditions of sludge. As identification of the microfauna species is difficult and time-consuming, we recommend using microfauna functional groups to evaluate the performance of the activated sludge system.

关键词： microfauna activated sludge indicators sludge biotic index (SBI)

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Holomorphic Deformations of the Ricci-flat ?-manifolds

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Acta Mathematica Sinica,English Series 2016年第6期32卷 643-658页

作者： Hai sheng liu Center of Mathematical Sciences Zhejiang University Hangzhou 310027 P. R. China

We present a construction of globally convergent power series of integrable Beltrami differentials on the Ricci-flat -manifolds and also a construction of global canonical family of holomorphic （n, 0）-forms on the... 详细信息

关键词： Deformations of complex structures Ricci-flat -manifold

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Improving the Intermittent Discharge Performance of Mg–Air Battery by Using Oxyanion Corrosion Inhibitor as Electrolyte Additive

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Acta Metallurgica Sinica(English Letters) 2016年第11期29卷 1019-1024页

作者： Yan-Chun Zhao Guang-sheng Huang Gui-lin Gong Ting-Zhuang Han Da-biao Xia Fu-sheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University

A widely used oxyanion corrosion inhibitor（Li2CrO4） was used as electrolyte additive（3.5 wt% Na Cl solution was used as electrolyte solution） for Mg–air battery. The potentiodynamic polarization tests showed that the presence of 0.1 wt% Li2CrO4in the Na Cl electrolyte reduced enormously the corrosion current density of the tested AZ31 Mg *** to the intermittent discharge tests, the use of 0.1 wt% Li2CrO4 as electrolyte additive increased the anode efficiency of the Mg–air battery by 28.4%. The addition of 0.1 wt% Li2CrO4reduced the anode self-corrosion rate of the battery in the intermittent stage effectively. The product film after discharge was observed by scanning electron microscope, and the Mg–air battery containing 0.1 wt% Li2CrO4has a loose product film, which is beneficial to its discharge performance. So using Li2CrO4 as electrolyte additive could improve the intermittent discharge performance of Mg–air battery. And the use of oxyanion corrosion inhibitor as electrolyte additive may be an excellent way to improve the intermittent discharge performance of Mg–air battery.

关键词： Mg alloys Corrosion Mg-air battery Intermittent discharge performance Anode efficiency

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Facile synthesis of a 4-anilinoquinazoline dimer by Suzuki cross-coupling reaction

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Chinese Chemical Letters 2011年第9期22卷 1033-1035页

作者： Shao Peng Chen Yue Sun sheng biao Wan Tao Jiang Key Laboratory of Marine Drugs Chinese Ministry of Education Shandong Provincial Key Laboratory of Glycoscience & Glycotechnology School of Medicine and Pharmacy Ocean University of China Qingdao 266003 China

A novel 4-anilinoquinazoline dimer linked by a carbon-carbon bond in the C-7 position was synthesized via a one step Suzuki cross-coupling reaction. All structures of new compounds were characterized by ^1H NMR, ^13C NMR, and HRMS. The inhibition rate of the synthetic 4-anilinoquinazoline dimer 8 against epidermal growth factor receptor-tyrosine kinase enzymes （EGFR） in vitro was 44.4% at the concentration of 5.5 μmol/L.

关键词： Quinazoline Suzuki reaction: Dimer EGFR Synthesis

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Vanishing Theorem for Irreducible Symmetric Spaces of Noncompact Type

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Acta Mathematica Sinica,English Series 2010年第2期26卷 361-368页

作者： Xu sheng liu School of Mathematical Sciences Fudan University Shanghai 200433 P. R. China

We prove the following vanishing theorem. Let M be an irreducible symmetric space of noncompact type whose dimension exceeds 2 and M ≠SO0（2, 2）/SO（2） × SO（2）. Let π ： E →＊ M be any vector bundle. Then any E-valued L2 harmonic 1-form over M vanishes. In particular we get the vanishing theorem for harmonic maps from irreducible symmetric spaces of noncompact type.

关键词： vanishing theorem symmetric space harmonic form

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