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Influence of Replacement Level of Coal-series Kaolin on Hydration of Ordinary Portland Cement by X-ray Diffraction/Rietveld Method

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Journal of Wuhan University of Technology(Materials Science) 2019年第3期34卷 614-621页

作者： liu yuanyuan LEI Shaomin School of Civil and Architectural Engineering Yangtze Normal UniversityChongqing408100China School of Resource and vironment Engineering Wuhan University of TechnologyWuhan430070China Yichang Huilong Science and Technology Co. Ltd.Yichang443004China

The influence of replacement level of calcined coal-series kaolin(CCK) on hydration of ordinary Portland cement(OPC) was studied by X-ray diffraction(XRD)/Rietveld method. X-ray diffraction/Rietveld method was used to quantify the crystalline phase composition of the hydrated samples. Additionally, the morphology of hydrated samples was observed by scanning electron microscopy(SEM). The results showed that, calcium hydroxide(CH), ettringite(AFt) and amorphous phase content in hydrated samples decreased as the replacement level of CCK increased, while AFm and str?tlingite increased, which was caused by the combination of dilute, physical and pozzolanic effects. The hydration of anhydrous cement phases was accelerated by physical effect but hindered by the retardation effect of CCK. The role of each effects was discussed in detail to analyze the mechanism of OPC hydration with CCK addition. The SEM images showed that the shortening of AFt at 1 day and the denser texture at 28 days was observed with CCK addition, which was caused by the physical and pozzolanic effects, respectively.

关键词： calcined coal-series kaolin X-ray diffraction/rietveld method hydration cement paste morphology

Fucoidans from Thelenota ananas with 182.4 kDa Exhibited Optimal Anti-Adipogenic Activities by Modulating the Wnt/β-Catenin Pathway

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Journal of Ocean University of China 2021年第4期20卷 921-930页

作者： liu yuanyuan WANG Na TIAN Yingying CHANG Yaoguang WANG Jingfeng College of Food Science and Engineering Ocean University of ChinaQingdao 266003China Marine Biomedical Research Institute of Qingdao Qingdao 266061China

In this study,fucoidans were extracted from the sea cucumber Thelenota ananas(Ta-FUCs)by enzymatic *** products with molecular weights of 1380.3,524.0,182.4,and 110.3 kDa were obtained,and the Ta-FUC showing optimal anti-adipogenic activities was *** of MTT and Oil red O staining analyses showed that the Ta-FUCs inhibited the proliferation and differentiation of 3T3-L1 ***,Ta-FUCs significantly downregulated the key transcriptional factors,such as SREBP-1c,PPARγ,and C/EBPαof *** Ta-FUCs also activated Wnt/β-catenin pathway-related genes,such asβ-catenin,LRP5,and *** Ta-FUCs suppressed lipid accumulation in 3T3-L1 adipocytes possibly by decreasing the expression of genes ACC,FAS,ME,GPAT,DGAT,and PILN,which are important in the synthesis of fatty acids and triglycerides;and by increasing the expression of genes PPARα,CPT-1α,and ACOX,which are crucial in fatty acidβ-*** anti-adipogenic activities initially increased and then declined with decreasing molecular *** the Ta-FUCs,the 182.4 kDa Ta-FUC exhibited optimal *** study reports for the first time that Ta-FUCs can prevent obesity by regulating the differentiation and lipid accumulation of adipocytes.

关键词： fucoidan from Thelenota ananas molecular weight anti-adipogenic activities adipocyte differentiation lipid accumulation Wnt/β-catenin pathway

Genesis of Highly Fractionated I-Type Granites from Fengshun Complex:Implications to Tectonic Evolutions of South China

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Journal of Earth Science 2016年第3期27卷 444-460页

作者： Zuomin Zhou Changqian Ma Caifu Xie Lianxun Wang yuanyuan liu Wei liu State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China School of Earth Sciences East China University of TechnologyNanchang 330013China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 611756China Tianjin Research Institute for Water Transport Engineering M.O.T.Tianjin 300456China

The South China Block is characterized by the large-scale emplacement of felsic magmas and giant ore deposits during the Yanshanian. We present zircon Hf isotopic compositions, whole-rock major and trace element compositions of the Fengshun complex, located in eastern Guangdong Province, South China. The Fengshun complex is a multi-stage magmatic intrusion. It is composed of two main units, i.e., the Mantoushan（MTS） syeno-monzogranites, alkali feldspar granites and the Hulutian（HLT） alkali feldspar granites. LA-ICPMS zircon dating shows that the complex emplaced in 166–161 and 139±2 Ma, respectively. Geochemically, the MTS granites show relatively various geochemical compositions with low REE contents（87.76×10-6–249.71×10-6）, Rb/Sr ratios（1.19–58.93）, pronounced Eu negative anomaly（0.01–0.37） and low Nb/Ta ratios（2.40–6.82）. In contrast, the HLT granites exhibit relatively stable geochemical characteristics with high REE contents（147.35×10-6– 282.17×10-6）, Rb/Sr ratios（2.05–10.30） and relatively high Nb/Ta ratios（4.45–13.00）. The isotopic data of the MTS granites display relatively enriched values, with ISr varying from 0.708 2 to 0.709 7, εNd（t） from-7.8 to-6.9 and εHf（t） from-7.4 to-3.2, in comparison with those of the HLT which are ISr=0.703 05–0.704 77, εNd（t）=-5–-3.4 and εHf（t）=-0.7–1.8）. The two-stage model ages of the MTS granites（T2DM（Nd）=1.51–1.59 Ga and T2DM（Hf）=1.26–1.48 Ga） are also higher than those of the HLT granites（T2DM（Nd）=1.21–1.34 Ga and T2DM（Hf）=0.96–1.10 Ga）. Thus the MTS and HLT granites might originate from different sources. The former is more likely derived from partial melting of Meso-Proterozoic basement triggered by upwelling of asthenosphere and/or underplate of the basaltic magma and then extensive fractional crystallisation, similar to the genesis of Early Yanshanian granitoids of the EW-trending tectono-magmatism belt in the Nanling range. In comparison, the latter might have involved with asthenosphere component, similar to the Earl

关键词： Sr-Nd-Hf isotopes Late Mesozoic magmagtism highly fractionated I-type granite post-orogeny roll-back South China

Generation of arbitrary vector vortex beams on hybrid-order Poincaré sphere

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Photonics Research 2017年第1期5卷 15-21页

作者： Zhenxing liu yuanyuan liu Yougang Ke Yachao liu Weixing Shu Hailu Luo Shuangchun Wen Laboratory for Spin Photonics School of Physics and Electronics Hunan University

We propose theoretically and verify experimentally a method of combining a q-plate and a spiral phase plate to generate arbitrary vector vortex beams on a hybrid-order Poincaré sphere. We demonstrate that a vector vortex beam can be decomposed into a vector beam and a vortex, whereby the generation can be realized by sequentially using a q-plate and a spiral phase plate. The generated vector beam, vortex, and vector vortex beam are verified and show good agreement with the prediction. Another advantage that should be pointed out is that the spiral phase plate and q-plate are both fabricated on silica substrates, suggesting the potential possibility to integrate the two structures on a single plate. Based on a compact method of transmissive-type transformation, our scheme may have potential applications in future integrated optical devices.

关键词： Generation of arbitrary vector vortex beams on hybrid-order Poincar sphere

High-efficiency and safe synthesis of tonalid via two Friedel-Crafts reactions in continuous-flow microreactors

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Chinese Journal of Chemical Engineering 2022年第12期52卷 126-135页

作者： Yang Han yuanyuan liu Shiwei Wang Xuehui Ge Xiaoda Wang Ting Qiu Engineering Research Center of Reactive Distillation Fujian Province Higher Education InstitutesCollege of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou 362801China

Tonalid,an important fragrance ingredient with widespread applicatio n,was synthesized via two FriedelCrafts reactions,which were catalyzed by AlCl_(3).The traditional tonalid production was conducted in batch stirring tank reactors,suffering from low production capacity and the safety hazard of temperature *** solve these problems,the continuous-flow technologies were developed for the highefficiency and intrinsically safe synthesis of tonalid in *** AlCl_(3)was neatly homogenized in proper solvents by forming complex with reactant,which was a necessary step for the continuous synthesis in *** reaction conditions,including reactant molar ratio,catalyst concentration,temperature,and microchannel hydrodynamic diameter,were investigated for the two Friedel-Crafts reactions in micro *** optimized conditions,the yields of the two Friedel-Crafts reactions were 44.15%and 97.55%,*** comparison with the batch reactors,the reaction times of these two reactions could both be reduced by nearly two thirds in microreactors at the similar yield.

关键词： Microreactor Continuous synthesis Process intensification Tonalid Friedel-Crafts reaction

A discussion on evaluation criteria for crevice corrosion of various stainless steels

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Journal of Materials Science & Technology 2021年第5期64卷 29-37页

作者： Xuan Wu yuanyuan liu Yangting Sun Nianwei Dai Jin Li Yiming Jiang Department of Materials Science Fudan UniversityShanghai 200433China

In this study,crevice corrosion performances of a newly developed LDSS 2002 and three commercial stainless steels(AISI 304,AISI 316L and DSS 2205)were investigated and *** repassivation potential(ER,CREV),which was measured by the potentiodynamic-galvanostatic-potentiodynamic(PDGS-PD)test,was applicable to crevice corrosion evaluation of 304 and 316 L stainless ***,much lower(ER,CREV values were obtained for DSS 2205 and LDSS *** abnormal(ER,CREV values for duplex stainless steels may be related to the selective attack of the less corrosion-resistant phase,the lower corrosion potential in the crevice-like solution,and more crevice corrosion sites in the PD-GS-PD test.A critical chloride concentration of crevice corrosion(CCCCREV)measurement was introduced for crevice corrosion evaluation of various stainless *** derived CCCCREVwas proved to be a valid criterion for crevice corrosion evaluation of both the austenitic and duplex stainless *** order of crevice corrosion resistance of AISI 304≈LDSS 2002

关键词： Stainless steel Crevice corrosion Crevice repassivation potential Critical chloride concentration

Tuning the crystalline and electronic structure of ZrO_(2)via oxygen vacancies and nano-structuring for polysulfides conversion in lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第1期88卷 82-93,I0003页

作者： Shengnan Fu Chaowei Hu Jing Li Hongtao Cui yuanyuan liu Kaihua liu Yanzhao Yang Meiri Wang Shandong Key Laboratory for Chemical Engineering and Processing School of Chemistry&Chemical EngineeringYantai UniversityYantai 264000ShandongChina Key Laboratory for Special Functional Aggregate Materials of Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100ShandongChina

The recent emergence of tetragonal phases zirconium dioxide(ZrO_(2))with vacancies has generated significant interest as a highly efficient and stable electrocatalyst with potential applications in trapping polysulfides and facilitating rapid conversion in lithium-sulfur batteries(LSBs).However,the reduction of ZrO_(2)is challenging,even under strong reducing atmospheres at high temperatures and ***,the limited presence of oxygen vacancies results in insufficient active sites and reaction interfaces,thereby hindering practical ***,we successfully introduced abundant oxygen vacancies into ZrO_(2)at the nanoscale with the help of carbon nanotubes(CNTs-OH)through hydrogen-etching at lower temperatures and *** introduced oxygen vacancies on ZrO_(2-x)/CNTs-OH can effectively rearrange charge distribution,enhance sulfiphilicity and increase active sites,contributing to high ionic and electronic transfer kinetics,strong binding energy and low redox barriers between polysulfides and ZrO_(2-x).These findings have been experimentally validated and supported by theory *** a result,LSBs assembled with the ZrO_(2-x)/CNTs-OH modified separators demonstrate excellent rate performance,superior cycling stability,and ultra-high sulfur ***,at high sulfur loading of 6 mg cm^(-2),the area capacity is still up to 6.3 mA h cm^(-2).This work provides valuable insights into the structural and functional optimization of electrocatalysts for batteries.

关键词： Lithium-sulfur batteries Oxygen vacancies Zirconium dioxide/carbon nanotubes with–OH Improved redox kinetics Superior cycling stability

Synthesis and in vitro Evaluation of Manganese（Ⅱ）-porphyrin Modified with Chitosan Oligosaccharides as Potential MRI Contrast Agents

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Chemical Research in Chinese Universities 2014年第4期30卷 549-555页

作者： liu Yun HUANG Yan BOAMAH Peter Osei ZHANG Qi liu yuanyuan HUA Mingqing School of Chemistry and Chemical Engineering Jiangsu University Zhenjiang 212013 P. R. China Hainan Provincial Key Lab of Fine Chemistry Hainan University Haikou 570228 P. R. China

Mn-TCPP-CSn（n=6,1 1,20） as a type of potential magnetic resonance imaging（MRI） contrast agents were synthesized via manganese（Ⅱ） meso-tetra（4-carboxyphenyl） porphyrin（Mn-TCPP） modified with chitosan oligosaccharides（CSn）.Experimental data of infared（IR）,UV-Vis,MS,inductively coupled plasma-atomic emission spectrometer（ICP-AES） and size exclusion chromatography evidenced the formation of Mn-TCPP-CSn-The stability results show that Mn-TCPP-CSn in aqueous solution was stable enough to prevent Mn（Ⅱ） ions from *** magnetic properties in vitro indicate that Mn-TCPP-CS20 possesses higher longitudinal relaxivity（r1=10.38 L·mmol^-1·s^-1） in aqueous solution than unmodified porphyrin Mn-TCPPNa4[manganese（Ⅱ） meso-tetra（4-carboxyphenyl） porphyrin,tetrasodium salt]（r1=5.10 L·mmol^-1·s^-1） and the commercial contrast agent Gd-DTPA（r1=4.05 L·mmol^-1·s^-1）.The preliminary T1-weighted flash image studies in vitro show that the contrast and the imaging signal of Mn-TCPP-CSn were superior to those of Mn-TCPPNa4 and Gd-DTPA under the same *** 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay shows that Mn-TCPP-CSn has a good *** addition,the thermodynamical parameters（ΔH〈0,ΔS〈0,ΔG〈0） of Mn-TCPP-CSn bound to bovine serum albumin（BSA） show that Mn-TCPP-CSn could bind to BSA spontaneously,where the binding complex was stabilized mainly by van der Waals interactions and hydrogen *** results suggest that Mn-TCPP-CSn have the advantage of becoming a potential MRI contrast agent.

关键词： MRI contrast agent Porphyrin Chitosan oligosaccharide Relaxivity T1-Weighted flash image

Studies on Intestinal Transport of Ginsenoside Compatibility with Veratrum nigrum via Caco-2 Cell Monolayer Model Coupled with UPLC-ESI-MS Method

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Chemical Research in Chinese Universities 2015年第6期31卷 914-918页

作者： MA Yinghui liu yuanyuan WEI Mengying SONG Fengrui liu Zhongying PI Zifeng College of Pharmacy Jilin University Changchun 130021 P. R. China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

The Caco-2 cells have been recognized as effective tools to be applied to imitating the drug absorption in human intestine for the transport of drug. Herein, Caco-2 cell monolayer model was used to study the transport of the ginsenoside compatibility with Veratrum nigrum in different proportions. A specific high performance liquid chro- matography-electrospray ionization-mass spectrometry（HPLC-ESI-MS） method was developed for the semiquantita- tive determination of ginsenoside in intestinal transport with Dioscin as an internal standard. For the Caco-2 model constructed, two influencing factors were investigated, including time and concentration. The results suggest that the absorption of ginsenoside Re, Rgl, Rbl, Rc, Rb2 and Rd are time- and concentration-dependent and the excretions of Rbl, Rc, Rb2 and Rd have a relatronship with some transport proteins. The bioavailability of the ginsenosides has reduced compared to the single Panax ginseng extract when compatibility with a certain amount of Veratrum nigrum.

关键词： High performance liquid chromatography-electrospray ionization-mass spectroscopy(HPLC-ESI-MS) Panax ginseng Ginsenoside Veratrum nigrum Transport Caco-2 cell monolayer model