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Corrosion resistance of biodegradable polymeric layer-by-layer coatings on magnesium alloy AZ31

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Frontiers of Materials Science 2016年第2期10卷 134-146页

作者： Lan-Yue CUI Rong-Chang ZENG xiao-xiao ZHU ting-ting PANG Shuo-Qi LI Fen ZHANG College of Materials Science and Engineering Shandong University of Science and Technology Qingdao 266590 China State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology Qingdao 266590 China

Biocompatible polyelectrolyte multilayers （PEMs） and polysiloxane hybrid coatings were prepared to improve the corrosion resistance of biodegradable Mg alloy AZ31. The PEMs, which contained alternating poly（sodium 4-styrenesulfonate）（PSS） and poly（allylamine hydrochloride）（PAH）, were first self-assembled on the surface of the AZ31 alloy substrate via electrostatic interactions, designated as （PAH/PSS）s/AZ31. Then, the （PAH/PSS）5/AZ31 samples were dipped into a methyltrimethoxysilane （MTMS） solution to fabricate the PMTMS films, designated as PMTMS/（PAH/PSS）5/AZ31. The surface morphologies, microstructures and chemical compositions of the films were investigated by FE-SEM, FTIR, XRD and XPS. Potentiodynamic polarization, electro- chemical impedance spectroscopy and hydrogen evolution measurements demonstrated that the PMTMS/（PAH/PSS）s/AZ31 composite film significantly enhanced the corrosion resistance of the AZ31 alloy in Hank＇s balanced salt solution （HBSS）. The PAH and PSS films effectively improved the deposition of Ca-P compounds including Ca3（PO4）2 and hydroxyapatite （HA）. Moreover, the corrosion mechanism of the composite coating was discussed. These coatings could be an alternative candidate coating for biodegradable Mg alloys.

关键词： magnesium alloy polyelectrolyte polysiloxane corrosion layer-by-layer

Quantifying the effects of long-term news on stock markets on the basis of the multikernel Hawkes process

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Science China(Information Sciences) 2021年第9期64卷 44-56页

作者： xiao DING Jihao SHI Junwen DUAN Bing QIN ting LIU Research Center for Social Computing and Information Retrieval

Recent studies have revealed that long-term financial news can affect stock markets. However,previous research mainly focuses on modeling the short-term effects of financial news and suffers from the weak ability of quantifying the time-decaying influence of financial news. To fill this gap, this study introduces the Hawkes process to estimate the time-decaying influence of long-term financial news. However, the performance of the conventional Hawkes process is sensitive to the choice of kernel functions. Hence, we propose a novel multikernel-powered Hawkes process framework, which uses multiple kernels to model different time-decaying rates, thus alleviating the instability of our proposed Hawkes process based prediction *** results show that the proposed framework yields state-of-the-art stock market prediction accuracies on 515 listed companies and gains more profits in market trading simulation compared with baseline methods. News-based stock prediction can complement studies on price-volume-based stock prediction.

关键词： Hawkes process multikernel function stock market prediction long-term news effects

Comparative studies on promotional effect of Pr_(6)O_(11),Nd_(2)O_(3)and Sm_(2)O_(3)on Ni-SiO_(2) for pressurized carbon dioxide reforming of methane

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Journal of Rare Earths 2023年第6期41卷 830-838,I0002页

作者： Bin Li ting Li Yong-Shan xiao Zhong-Wen Liu Key Laboratory of Syngas Conversion of Shaanxi Province School of Chemistry&Chemical EngineeringShaanxi Normal UniversityXi'an 710119China

The 7 wt%rare earth metal oxide promoted Ni-SiO_(2) catalysts of Ni-7Pr_(6)O_(11)-SiO_(2),Ni-7Nd_(2)O_(3)-SiO_(2),and Ni-7Sm_(2)O_(3)-SiO_(2) were prepared by the complex-decomposition method,and were comparatively evaluated for pressurized carbon dioxide reforming of methane(CRM)under severe conditions of 750℃,1.0 MPa,CH_(4)/CO_(2)=1,and gas hourly space velocity of 53200 mL/(g·h).The addition of rare earth metal oxide does not affect the Ni dispersion,and all of the catalysts show similarly high Ni dispersion of16.0%±0.2%.As a result,all of the catalysts are highly active for pressurized CRM,the initial CH_(4) conversions of which approach the thermodynamic equilibrium(47.0%±0.2%).In contrast,a clearly favorable effect of the added rare earth metal oxide on the stability of Ni-SiO_(2)was revealed from the CRM results for a time-on-stream of 50 h,and the highest stability without an observable decrease in the conversions of CH_(4)and CO_(2)was obtained over Ni-7Sm_(2)O_(3)-SiO_(2).Based on the characterization results of thermogravimetric differential scanning calorimetry(TG-DSC)and transmission electron microscopy(TEM),the improved stability of Ni-7Pr_(6)O_(11)-SiO_(2),Ni-7Nd_(2)O_(3)-SiO_(2),and Ni-7Sm_(2)O_(3)-SiO_(2)for pressurized CRM was manifested mainly as the suppressed formation of carbon nanotubes over the catalyst surface,the extent of which is dependent on the specific rare earth metal ***,the consecutive temperature programmed surface reaction of CH_(4),CO_(2),and O_(2)over Ni-7Sm_(2)O_(3)-SiO_(2)vigorously reveals that the addition of Sm_(2)O_(3)into Ni-SiO_(2)inhibits the CH_(4)decomposition but enhances the oxidization of the carbon species by CO_(2),leading to the well-balanced rates for forming and removing the coke over Ni-7Sm_(2)O_(3)-SiO_(2).These findings are not only beneficial to deeply understanding the promotional effect of rare earth metal oxides on Ni-based catalysts for CRM,but also important for extending the application of

关键词： Carbon dioxide Methane Pressurized reforming Rare earth metal oxide Nickel

电极电位对L-蛋氨酸分子吸附构型影响的表面增强拉曼光谱

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上海师范大学学报（自然科学版） 2009年第1期38卷 75-82页

作者：张婷婷曹晓卫田培培张丹钱庆庆章宗穰上海师范大学生命与环境科学学院上海200234

利用电化学现场表面增强拉曼光谱技术研究了在粗糙化金电极和银电极表面吸附的L-蛋氨酸自组装单分子膜结构随电位改变的特征.实验结果表明:在外加电位0^-0.6V范围内,L-蛋氨酸主要是通过硫原子和去质子化羧基2个吸附位点与银电极表面产... 详细信息

利用电化学现场表面增强拉曼光谱技术研究了在粗糙化金电极和银电极表面吸附的L-蛋氨酸自组装单分子膜结构随电位改变的特征.实验结果表明:在外加电位0^-0.6V范围内,L-蛋氨酸主要是通过硫原子和去质子化羧基2个吸附位点与银电极表面产生相互作用的;而在金电极表面表现为分子中的氨基、去质子化羧基和硫原子3个吸附位点随电位负移而改变的特征;另外,对于金电极表面吸附的L-蛋氨酸单分子膜而言,还伴随着吸附物分子由于分子内旋转等而引致的分子构型的转变.

关键词： L-蛋氨酸自组装单分子膜表面增强拉曼光谱电极电位

AN IMPROVED ARC-LENGTH METHOD AND APPLICATION IN THE POST-BUCKLING ANALYSIS FOR COMPOSITE STRUCTURES

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Applied Mathematics and Mechanics(English Edition) 2002年第9期23卷 1081-1088页

作者： ZHU Ju-fen(朱菊芬) CHU xiao-ting(初晓婷) Department of Engineering Mechanics Dalian University of Technology Dalian116023 PR China Department of Engineering Mechanics Dalian University of Technology Dalian116023 PR China

Based on the conventional arc-length method, an improved arc-length method with high-efficiency is proposed. The weighted modifications with respect to the variation of structural stiffness and extra-interpolation modification by using the information of known equilibrium points are introduced to improve the incremental arc-length. An approximate expansion method for the accumulated and expected arc-length is used to ensure the convergence at given load levels in large range of applications. Numerical results show that the improved arc-length method has well adaptability and higher efficiency in the post-buckling analysis of plates and shells structures for tracing whole load-deflection path and obtaining the convergence values at any specified load levels.

关键词： nonlinear finite element analysis arc-length method

Spatial channel pairing based coherent combining for relay networks

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 938-945页

作者： Feng SHU xiao-hui HUANG Jin-song HU ting-ting LIU Ri-qing CHEN xiao-hu YOU Jun LI Jin WANG College of Computer and Information Sciences Fujian Agriculture and Forestry University School of Electronic and Optical Engineering Nanjing University of Science and Technology National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave Propagation National Mobile Communications Research Laboratory Southeast University

In this paper, spatial channel pairing(SCP) is introduced to coherent combining at the relay in relay networks. Closed-form solution to optimal coherent combining is derived. Given coherent combining, the approximate SCP solution is presented. Finally, an alternating iterative structure is developed. Simulation results and analysis show that, given the symbol error rate and data rate, the proposed alternating iterative structure achieves signal-to-noise ratio gains over existing schemes in maximum ratio combining(MRC) plus matched filter,MRC plus antenna selection, and distributed space-time block coding due to the use of SCP and iterative structure.

关键词： Spatial channel pairing Coherent combining Alternating iterative structure Symbol error rate Distributed space-time block coding

Pre-and post-pollination barriers between two exotic and five native Sagittaria species:Implications for species conservation

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Plant Diversity 2023年第4期45卷 456-468页

作者： ting-ting Zou Sen-Tao Lyu Qi-Lin Jiang Shu-He Shang xiao-Fan Wang Laboratory of Plant Systematics and Evolutionary Biology College of Life SciencesWuhan UniversityWuhan 430072China

Anthropogenic introduction of species has resulted in a breakdown of geographical barriers and hybridization in previously allopatric ***,examining hybridization proneness of exotic species contributes to revealing its potential ***,reproductive barriers may be strengthened or weakened due to long-term geographical isolation for these newly sympatric ***,few studies have evaluated multiple barriers between alien and native *** this study,we quantified the importance of four pre-pollination barriers(phenological,floral traits,pollen production,and floral constancy)and four post-pollination barriers(pollen-pistil incompatibility,seed set,seed viability,and seedling survival)between two introduced and five native Sagittaria *** showed that introduced *** was cross-compatible with two native species,whereas introduced *** was incapable of hybridizing with any native *** barriers were asymmetric within species pairs and multiple barriers acted in concert to maintain species *** barriers contributed more to total reproductive isolation in native species,whereas prepollination barriers played a stronger role in total reproductive isolation for two introduced *** set was the only barrier that was positively correlated with genetic *** results provide a perspective to better understand reproductive barriers for secondary contact *** highlight the importance of monitoring hybridization events before human introduction and the possible conservation strategies to remove invasive species with hybridization proneness.

关键词： Alismataceae Introduced species Conservation Hybridization Reproductive isolation Sagittaria

Network Pharmacology in Research of Chinese Medicine Formula: Methodology, Application and Prospective

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Chinese Journal of Integrative Medicine 2020年第1期26卷 72-80页

作者： LUO ting-ting LU Yuan YAN Shi-kai xiao Xue RONG Xiang-lu GUO Jiao Institute of Traditional Chinese Medicine Guangdong Pharmaceutical UniversityGuangzhou 510006China Guangdong Metabolic Diseases Research Center of Integrated Chinese and Western Medicine Guangzhou 510006China School of Pharmacy Shanghai Jiao Tong UniversityShanghai 200240China

Chinese medicine(CM) is usually prescribed as CM formula to treat disease. The lack of effective research approach makes it difficult to elucidate the molecular mechanisms of CM formula owing to its complicated chemical compounds. Network pharmacology is increasingly applied in CM formula research in recent years, which is identified suitable for the study of CM formula. In this review, we summarized the methodology of network pharmacology, including network construction, network analysis and network verification. The aim of constructing a network is to achieve the interaction between the bioactive compounds and targets and the interaction between various targets, and then find out and validate the key nodes via network analysis and network verification. Besides, we reviewed the application in CM formula research, mainly including targets discovery, bioactive compounds screening, toxicity evaluation, mechanism research and quality control research. Finally, we proposed prospective in the future and limitations of network pharmacology, expecting to provide new strategy and thinking on study for CM formula.

关键词： network pharmacology Chinese medicine formula targets discovery mechanism research quality control research

Clinical outcomes of transcatheter selective superior mesenteric artery urokinase infusion therapy vs transjugular intrahepatic portosystemic shunt in patients with cirrhosis and acute portal vein thrombosis

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World Journal of Gastroenterology 2017年第41期23卷 7470-7477页

作者： ting-ting Jiang xiao-Ping Luo Jian-Ming Sun Jian Gao Department of Gastroenterology and Hepatology Second Affiliated HospitalChongqing Medical University Department of Radiology Second Affiliated HospitalChongqing Medical University Department of Vascular Surgery Second Affiliated HospitalChongqing Medical University

AIM To compare the outcomes of transcatheter superior mesenteric artery(SMA) urokinase infusion and transjugular intrahepatic portosystemic shunt(TIPS) for acute portal vein thrombosis(PVT) in *** From January 2013 to December 2014, patients with liver cirrhosis and acute symptomatic PVT who met the inclusion criteria were randomly assigned to either an SMA group or a TIPS group. The two groups accepted transcatheter selective SMA urokinase infusion therapyand TIPS, respectively. The total follow-up time was24 mo. The primary outcome measure was the change in portal vein patency status which was evaluated by angio-computed tomography or Doppler *** outcomes were rebleeding and hepatic *** A total of 40 patients were enrolled, with 20 assigned to the SMA group and 20 to the TIPS group. The symptoms of all patients in the two groups improved within 48 h. PVT was improved in 17(85%) patients in the SMA group and 14(70%) patients in the TIPS group. The main portal vein(MPV) thrombosis was significantly reduced in both groups(P < 0.001), and there was no significant difference between them(P= 0.304). In the SMA group, superior mesenteric vein(SMV) thrombosis and splenic vein(SV) thrombosis were significantly reduced(P = 0.048 and P = 0.02),which did not occur in the TIPS group. At 6-, 12-,and 24-mo follow-up, in the SMA group and the TIPS group, the cumulative rates free of the first episode of rebleeding were 80%, 65%, and 45% vs 90%, 80%,and 60%, respectively(P = 0.320); the cumulative rates free of the first episode of hepatic encephalopathy were 85%, 80%, and 65% vs 50%, 40%, and 35%,respectively(P = 0.022).CONCLUSION Transcatheter selective SMA urokinase infusion and TIPS are safe and effective for acute symptomatic PVT in cirrhosis.

关键词： Cirrhosis Portal vein thrombosis Superior mesenteric artery Urokinase Transjugular intrahepatic portosystemic shunt