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A method to Estimate Dynamic Responses of VLFS Based on Multi-Floating-Module Model Connected by Elastic Hinges

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China Ocean Engineering 2021年第5期35卷 687-699页

作者： HUANG Heng CHEN Xu-jun liu jun-yi MIAO Yu-ji JI Song College of Field Engineering Army Engineering University of PLANanjing 210007China China Ship Scientific Research Center Wuxi 214082China

Based on the elastic foundation beam theory and the multi-floating-module hydrodynamic theory,a novel method is proposed to estimate the dynamic responses of VLFS(Very Large Floating Structure).In still water,a VLFS can be simplified as an elastic foundation beam model or a multi-floating-module model connected by elastic *** to equivalent displacement of the two models in static analysis,the problem of rotation stiffness of elastic hinges can be ***,based on the potential flow theory,the dynamic responding analysis of multi-floatingmodule model under wave loads can be computed in ANSYS-AQWA *** assembling the time domain analysis results of each module,the dynamic responses of the VLFS can be *** of the method is conducted through a series of comparison calculations,which mainly includes a continuous structure and a three-part structure connected by hinges in regular *** results of this paper method show a satisfactory agreement with the experiment and calculation data given in relative references.

关键词： Very Large Floating Structure(VLFS) dynamic responses elastic foundation beam multi-floatingmodule model elastic hinge

低温水浴制备BiVO_(4)光催化材料用于可见光降解RhB研究

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陕西科技大学学报 2025年第1期43卷 115-125页

作者：余泽翰曹丽云冯亮亮黄剑锋赵勇刘一军董军乐陕西科技大学材料科学与工程学院陕西省国际科技合作基地陕西西安710021 蒙娜丽莎集团股份有限公司广东佛山528211 广西蒙娜丽莎新材料有限公司广西梧州543000

N型半导体BiVO_(4)是降解有机污染物最具应用前景的可见光光催化材料之一.然而,纯BiVO_(4)由于光生电子-空穴对复合过快,载流子传输速率低等问题限制着其光催化能力.表面活性剂不仅可以调节BiVO_(4)的形貌和粒径大小,还可以通过增大比... 详细信息

N型半导体BiVO_(4)是降解有机污染物最具应用前景的可见光光催化材料之一.然而,纯BiVO_(4)由于光生电子-空穴对复合过快,载流子传输速率低等问题限制着其光催化能力.表面活性剂不仅可以调节BiVO_(4)的形貌和粒径大小,还可以通过增大比表面积来增多反应活性位点,以提高光催化活性.本研究以十二烷基硫酸钠(SDS)为表面活性剂,通过简单的一步水浴法制备出一系列不同摩尔比的SDS/BiVO_(4)光催化剂,并在500 W氙灯下照射降解有机污染物罗丹明B并评价其光催化降解性能.结果表明:10%SDS/BiVO_(4)具有最高的光催化降解效率,BET表征和光电流测试证实了SDS的引入不仅增大了BiVO_(4)的比表面积为光催化反应提供更多的活性位点,而且提高了光生载流子分离和迁移效率.此外,自由基捕获实验表明:·OH和h+在光催化降解罗丹明B过程中是起主要作用的反应基团.该研究方法绿色环保且易于实现,为制备高效可见光光催化剂用于降解有机污染物提供了新思路.

关键词：光催化表面活性剂降解反应有机污染物

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Fabrication and characterization of anodic oxide films on a Ti-10V-2Fe-3Al titanium alloy

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 96-100页

作者： Jian-hua liu jun-lan yi Song-mei Li Mei Yu Yong-zhen Xu School of Materials Science and Engineering Beihang University Beijing 100191 China

Anodic oxide films of the titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate electrolyte without hydrofluoric acid or fluoride were fabricated. The morphology, components, and microstructure of the films were characterized by scanning electron microscopy （SEM）, X-ray photoelectron spectroscopy （XPS）, X-ray diffraction （XRD）, and Raman spectroscopy. The results showed that the films were thick, uniform, and nontransparent. Such films exhibited sedimentary morphology, with a thickness of about 3 μm, and the pore diameters of the deposits ranged from several hundred nanometers to 1.5 μm. The films were mainly titanium dioxide. Some coke-like deposits, which may contain or be changed by OH, NH, C-C, C-O, and C=O groups, were doped in the films. The films were mainly amorphous with a small amount of anatase and rutile phase.

关键词： titanium alloys anodic oxide films titanium dioxide pulse current method

The synthesis of porphyrin-anthraquinone dyad via an azo-rearrangement

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Chinese Chemical Letters 2011年第5期22卷 539-542页

作者： Cheng Jie Li Ya Qing Feng Xiu jun liu Tian yi Zhang School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

One novel porphyrin P-Q2 is planned to be synthesized by condensation between ATPP and ***,after separation by chromatography and characterization with IR,~1H NMR,HR-MS and X-ray,P-Q1 is obtained *** the structure of P-Q1 with that of P-Q2,it is realized that an intramolecular cyclization rearrangement takes place when the azo group is situated in the O-position to the amido *** rearrangement offers a new way to prepare indazole *** addition,the spectral properties of P-Q1 have been studied by UV-vis and steady state fluorescence *** fluorescence quenching is observed in the preliminary emission spectrum due to the proposed electron transfer from the excited porphyrin to the anthraquinone moieties.

关键词： Porphyrin Anthraquinone Azo-rearrangement Fluorescence quenching

Regioselective Deprotection of 1,3-Dibenzyl-5-(N,N-dimethylamino)-6-phenylethyluracil

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Chemical Research in Chinese Universities 2008年第6期24卷 735-738页

作者： LI A-min WANG Xiao-wei ZHANG Zhi-li CHENG Zhi-jian liu jun-yi Department of Chemical Biology State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Beijing 100083 P R. China Department of Chemistry College of Jiujiang Jiujiang 33200 P R. China

The deprotection of 1,3-dibenzyl-5-（N,N-dimethylamino）-6-phenyl-ethyluracil I was investigated. A practical, regioselective N3 deprotection of compound I was performed with excellent yield using cyclohexene as a hyd... 详细信息

关键词： 1,3-Dibenzyl-5-(N,N-dimethylamino)-6-phenylethyluracil Benzylprotecting Deprotection

In vivo study of extracellular matrix coating enhancing fixation of the pedicle screw-bone＇s interface

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Chinese Medical Journal 2011年第23期124卷 3945-3952页

作者： liu Guo-min ZHANG Xing-yi XU Chuan-jie ZHU Xiao-min WANG jun liu yi Department of Ortiaopedics Department of Thoracic Surgery Changchun Jilin 130041 China

Based on in vivo research on the effect of the coating of the extracellular matrix composition of pedicle screws on the conduction and induction of bone formation in young sheep, the aim of this study was to investigate the application of coated pedicle screws in sheep with scoliosis whose spines are under constant development. Methods Four groups of pedicle screws were randomly implanted into bilateral L2-L5 pedicles of 2.5- to 3-month-old sheep. A static experiment was performed on one side and a loading test was performed on the other side by implanting connecting rods at the L2-L3 and L4-L5 segments. The changes in the force on the coated screws and the combination of the surface of the coated screws with the surrounding bone in the growth process of young sheep＇s spines with aging were observed. After 3 months, the lumbar vertebrae with the screws were removed and examined by micro-CT, histological, and biomechanical analyses. Results Under nonloading conditions, there is bone formation around the surfaces of coated screws. The bone forming on the surface of collagen/chondroitin sulfate/hydroxyapatite coating of pedicle screws is the most, the one of the collagen / chondroitin sulfate coating and hydroxyapatite coating is followed, and no significant difference between the two groups. In terms of the trabecular bone morphology parameters of the region of interest around the surface of the pedicle screws, such as bone mineral content, bone mineral density, tissue mineral content, tissue bone mineral density, bone volume fraction, and connection density, those associated with collagen/chondroitin sulfate/hydroxyapatite coatings are largest and those unassociated with coatings are smallest. Under nonloading conditions, the pullout strength of the collagen/chondroitin sulfate/hydroxyapatite-coated screws was largest, and that of the uncoated screws was minimal （P 〈0.01）. Under loading conditions, the maximum pullout strength of each group of pedicle screws was less

关键词： hydroxyapatite collagen chondroitin sulfate micro-CT biomechanics

Compensation mechanism for ecological interests of Erhai Lake tourist destination in Dali, Yunnan province

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Ecological Economy 2021年第1期17卷 70-74页

作者： liu yi-jun XIANG Xiao-ming Dianchi College of Yunnan University Kunming 650000CHINA

Erhai Lake in Dali,Yunnan province,is the"Mother Lake"of the Bai *** has superior location advantages,remarkable comprehensive functions and profound historical *** is the cradle of Dali’s politics,economy and culture,and also the foundation of the sustainable economic development of the Autonomous *** the government put great efforts to govern Erhai Lake,the original interest demand structure of the surrounding residents was broke down,and the problems of interest friction and interest conflict became the practical problems faced by the *** paper will analyze the compensation mechanism of Erhai Lake’s ecological interests from the aspects of ecological damage,stakeholders,interests,tourism transformation and so on,so as to provide a reference for the transformation and upgrading of national tourism destinations and tourism industry.

关键词： ecological civilization interest demand compensation mechanism

Application of Computed Tomography Virtual Noncontrast Spectral Imaging in Evaluation of Hepatic Metastases： A Preliminary Study

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Chinese Medical Journal 2015年第5期128卷 610-614页

作者： Shi-Feng Tian Ai-Lian liu Jing-Hong liu Mei-Yu Sun He-Qing Wang yi-jun liu Department of Radiology First Affiliated Hospital of Dalian Medical University Dalian Shenyang 116011 China

Objective：The objective was to qualitatively and quantitatively evaluate hepatic metastases using computed tomography （CT） virtual noncontrast （VNC） spectral imaging in a retrospective ***：Forty hepatic metastases patients underwent CT scans including the conventional true noncontrast （TNC） and the tri-phasic contrast-enhanced dual energy spectral scans in the hepatic arterial,portal venous,and equilibrium *** tri-phasic spectral CT images were used to obtain three groups of VNC images including in the arterial （VNCa）,venous （VNCv）,and equilibrium （VNCe） phase by the material decomposition process using water and iodine as a base material *** image quality and the contrast-to-noise ratio （CNR） of metastasis of the four groups were compared with ANOVA *** metastasis detection rates with the four nonenhanced image groups were calculated and compared using the Chisquare ***：There were no significant differences in image quality among TNC,VNCa and VNCv images （P 〉 0.05）.The quality of VNCe images was significantly worse than that of other three groups （P 〈 0.05）.The mean CNR of metastasis in the TNC and VNCs images was 1.86,2.42,1.92,and 1.94,respectively; the mean CNR of metastasis in VNCa images was significantly higher than that in other three groups （P 〈 0.05）,while no statistically significant difference was observed among VNCv,VNCe and TNC images （P 〉 0.05）.The metastasis detection rate of the four nonenhanced groups with no statistically significant difference （P 〉 0.05）.Conclusions：The quality of VNCa and VNCv images is identical to that of TNC images,and the metastasis detection rate in VNC images is similar to that in TNC *** images obtained from arterial phase show metastases more ***,VNCa imaging may be a surrogate to TNC imaging in hepatic metastasis diagnosis.

关键词： Contrast-to-noise Ratio Hepatic Metastasis Virtual Noncontrast Imaging

有关社会焦点问题的群体研讨实验——定性综合集成的一种实践

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系统工程理论与实践 2007年第3期27卷 42-49页

作者：唐锡晋刘怡君中国科学院数学与系统科学研究院北京100080

社会生活中的一些焦点问题可视为非结构问题或者恶劣问题(wicked problem),其问题的解决过程本质上是寻找或者探测出问题的结构,在向结构化问题的转化过程重点通过对结构问题的解决而综合得到对原问题的一些解决方案.此类工作大多体现... 详细信息

社会生活中的一些焦点问题可视为非结构问题或者恶劣问题(wicked problem),其问题的解决过程本质上是寻找或者探测出问题的结构,在向结构化问题的转化过程重点通过对结构问题的解决而综合得到对原问题的一些解决方案.此类工作大多体现为群体活动.为此,介绍了基于自主研制的支持发散型群体思考的群体研讨环境(GAE)所进行的一个有关日本入常问题的群体研讨的一个试验.通过对试验结果的分析,阐述了GAE对于非结构化问题求解过程中如何支持人们感悟或者获取一些潜在线索乃至结构,在此基础上开展深入研究如定量建模,此即为综合集成方法求解复杂问题中的一种定性综合集成的实践.

关键词：群体研讨定性综合集成社会焦点问题 GAE