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Effect of irradiation on temperature performance of dispersioncompensation no-core cascade optical-fiber sensor coated with polydimethylsiloxane film

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Nuclear Science and Techniques 2022年第9期33卷 10-20页

作者： Fang Wang Qiu-Feng Wu Yu-Rong Jiang chan Jin Xiao-Hui Wang ben-Shang Zhang chun-Wang Ma college of Electronic and Electrical Engineering Henan Normal UniversityXinxiang 453007China Key Laboratory of Optoelectronic Sensing Integrated Application of Henan Province Xinxiang 453007China School of Physics Henan Normal UniversityXinxiang 453007China Engineering Laboratory of Intelligent Additive Manufacturing of Henan Province Xinxiang 453007China Key Laboratory of Interfacial Physics Technology Project Chinese Academy of SciencesShanghai 201800China Institute of Isotope Research Henan Academy of SciencesZhengzhou 450000China

A temperature measurement device can produce data deviations and can even be damaged in a high-dose radiation *** reduce the radiation damage to such a device and improve the temperature measurement accuracy in a radiation environment,a temperature sensor based on optical-fiber sensing technology is *** sensor has a cascade structure composed of a single-mode fiber(SMF),a dispersion-compensation fiber(DcF),a nocore fiber(NcF),and another SMF(SDNS).The DcF and NcF are coated with a polydimethylsiloxane(PDMS)film,which is a heat-sensitive material with high thermal optical and thermal expansion *** experiments,PDMS was found to produce an irradiation crosslinking effect after irradiation,which improved the temperature sensitivity of the SDNS *** experimental results showed that within a range of 30–100℃,the maximum temperature sensitivity after irradiation was 62.86 pm/℃,and the maximum transmission sensitivity after irradiation was 3.353×10^(-2)dB/℃,which were 1.22 times and 2.267 times the values before irradiation,*** addition,repeated temperature experiments verified that the SDNS sensor coated with the PDMS film had excellent temperature ***,it was found that with an increase in the irradiation intensity,the irradiation crosslinking degree of PDMS increased,and the temperature sensitivity of the sensor was *** proposed sensor could potentially be applied to temperature measurement in a nuclear-radiation environment.

关键词： ^(60)co-γirradiation Optical-fiber sensor Temperature performance PDMS Radiation crosslinking

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Metal-free multicomponent polymerization of activated diyne,electrophilic styrene and isocyanide towards highly substituted and functional poly(cyclopentadiene)

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Science china chemistry 2023年第3期66卷 863-869页

作者： Xinyue Liu Xueqin Yang Xin Li Jianwei Sun benzhao He Jacky W.Y.Lam ben Zhong Tang Department of chemistry and Hong Kong Branch of chinese National Engineering Research center for Tissue Restoration and Reconstruction Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsThe Hong Kong University of Science and TechnologyHong Kong 999077China center for Advanced Materials Research Beijing Normal University at ZhuhaiZhuhai 519085China School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen 518172China center for Aggregation-Induced Emission South China University of TechnologyGuangzhou 510640China

The development of a facile and efficient polymerization to prepare cyclopentadiene-containing polymers is of vital importance and highly desired. In this work, a metal-free multicomponent polymerization of activated diyne, electrophilic styrene and isocyanide for the preparation of highly substituted poly(cyclopentadiene) was established. Soluble and thermally stable polymers with high molecular weights are obtained in high yields under mild conditions. By introducing the tetraphenylethene or triphenylamine moiety into polymer backbones, the resultant polymers show unique aggregation-induced emission(AIE)characteristics. Interestingly, AIE polymers can also be generated in situ from non-AIE monomers. Moreover, the prepared polymers can generate photopatterns to function as photoresists and can also serve as visualizing agents to selectively stain the lipid droplets in live cells. This efficient polymerization will open up enormous opportunities for preparing functional cyclopentadiene-containing polymers applicable in diverse areas.

关键词： multicomponent polymerization activated alkynes highly substituted poly(cyclopentadiene)

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NH_(4)cl-assisted preparation of single Ni sites anchored carbon nanosheet catalysts for highly efficient carbon dioxide electroreduction

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Journal of Materials Science & Technology 2023年第11期142卷 1-9页

作者： Dan Ping Feng Yi Guiwei Zhang Shide Wu Shaoming Fang Kailong Hu ben Bin Xu Junna Ren Zhanhu Guo Henan Provincial Key Laboratory of Surface&Interface Science Henan Engineering Research Center of Chemical Engineering Separation Process IntensificationSchool of Material and Chemical EngineeringZhengzhou University of Light IndustryZhengzhou 450002China School of Materials Science and Engineering Harbin Institute of TechnologyShenzhen 518055China Mechanical and construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle upon Tyne NE18STUK college of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Department of chemical&Biomolecular Engineering Integrated Composites Lab(ICL)University of TennesseeKnoxvilleTN 37996USA

Single-atomic transition metal-nitrogen codoped carbon(M-N-c)are efficient substitute catalysts for noble metals to catalyze the electrochemical cO_(2) reduction reaction(cO_(2)RR).However,the uncontrolled aggregations of metal and serious loss of nitrogen species constituting the M-N_(x) active sites are frequently observed in the commonly used pyrolysis ***,single-atomic nickel(Ni)-based sheet-like electrocatalysts with abundant Ni-N_(4) active sites were created by using a novel ammonium chloride(NH_(4)cl)-assited pyrolysis *** aberration correction electron microscopy and X-ray absorption fine structure analysis clearly revealed that Ni species are atomically dispersed and anchored by N in Ni-N_(4) *** addition of NH_(4)cl optimized the mesopore size to 7-10 nm and increased the concentrations of pyridinic N(3.54 wt%)and Ni-N_(4)(3.33 wt%)*** synergistic catalytic effect derived from Ni-N_(4) active sites and pyridinic N species achieved an outstanding cO_(2) RR performance,presenting a high cO Faradaic efficiency(FE_(cO))up to 98% and a large cO partial current density of 8.5 mA cm^(-2) at a low potential of-0.62 V ***,the FE_(cO) maintains above 80% within a large potential range from -0.43 to -0.73 V *** work provides a practical and feasible approach to building highly active single-atomic catalysts for cO_(2) conversion systems.

关键词： cO_(2)reduction Electrocatalyst Single-atomic ni NH_(4)cl Pyridinic N

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Natural convection in a Horizontal cylinder with Partial Heating: Energy Efficiency Analysis

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Journal of Thermal Science 2020年第6期29卷 1531-1550页

作者： MAZGAR Akram JARRAY Khouloud HAJJI Fadhila ben NEJMA Faycal The Higher Institute of Applied Sciences and Technology of Sousse University of SousseTunisia-Ibn Khaldun StreetTaffala City4003 SousseTunisia The Preparatory Institute for Engineering Studies of Monastir University of MonastirTunisia-Rue Ibn El Jazzar5019 MonastirTunisia

The current study reports a numerical analysis of free convection of air in an isothermal horizontal cylinder,cooled and heated at different wall *** heater sizes are discussed in this *** first heated zone is spread across one-quarter of the sidewall;the second is uniformly distributed over the half of the wall and the third active wall covers three-quarters of the *** various locations are considered and examined for each active zone of the *** computation is carried out for Rayleigh number ranging from 102 to *** results characterizing heat transfer and flow features are achieved using an iterative model developed in cOMSOL *** effect of Rayleigh number on heat transfer and fluid flow characteristics within the cavity are *** attention is paid to the influence of heater location and heater size on energy *** is found that the mean Nusselt number and dimensionless velocity increase when increasing the Rayleigh ***,the optimal level of energy efficiency is achieved if the heating zone is centered at the upper part of the cylinder,regardless of the heater *** is also shown that the optimal configuration providing higher energy efficiency is obtained when three-quarters of the sidewall are locally heated,and more precisely,if the active zone is centered at the top of the cylinder.

关键词： natural convection cylinder partial heating energy efficiency Rayleigh number

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Evaluating the Potentials of PLSR and SVR Models for Soil Properties Prediction Using Field Imaging,Laboratory VNIR Spectroscopy and Their combination

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computer Modeling in Engineering & Sciences 2023年第8期136卷 1399-1425页

作者： Emna Karray Hela Elmannai Elyes Toumi Mohamed Hedi Gharbia Souham Meshoul Hamouda Aichi Zouhaier ben Rabah center of Mapping and Remote Sensing Tunis1073Tunisia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Digital Research centre of Sfax Sfax3021Tunisia Higher School of Agriculture of Mograne LR03AGR02SPADDUniversity of CarthageCarthage1054Tunisia

Pedo-spectroscopy has the potential to provide valuable information about soil physical,chemical,and biological ***,wemay predict soil properties usingVNIRfield imaging spectra(IS)such as Prisma satellite data or laboratory spectra(LS).The primary goal of this study is to investigate machine learning models namely Partial Least Squares Regression(PLSR)and Support Vector Regression(SVR)for the prediction of several soil properties,including clay,sand,silt,organic matter,nitrate NO3-,and calcium carbonate cacO_(3),using five VNIR spectra dataset combinations(%IS,%LS)as follows:c1(0%IS,100%LS),c2(20%IS,80%LS),c3(50%IS,50%LS),c4(80%IS,20%LS)and c5(100%IS,0%LS).Soil samples were collected at bare soils and at the upper(0–30 cm)*** data set has been split into a training dataset 80%of the collected data(n=248)and a validation dataset 20%of the collected data(n=61).The proposed PLSR and SVR models were trained then tested for each dataset *** to our results,SVR outperforms PLSR for both:c1(0%IS,100%LS)and c5(100%IS,0%LS).For Soil Organic Matter(SOM)prediction,it achieves(R^(2)=0.79%,RMSE=1.42%)and(R^(2)=0.76%,RMSE=1.3%),*** data fusion has improved the soil property *** highest improvement was obtained for the SOM property(R^(2)=0.80%,RMSE=1.39)when using the SVR model and applying the second combination c2(20% of IS and 80%LS).

关键词： Soil VNIR field imaging spectroscopy PLSR SVR VNIR data combination

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Zircon U-Pb dating and geochemical study of the Xianggou granite in the Ma'anqiao gold deposit and its relationship with gold mineralization

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Science china Earth Sciences 2010年第2期53卷 220-240页

作者： LEE ben State Key Laboratory of continental Dynamics Department of GeologyNorthwest University

Single zircon LA-IcP-MS U-Pb dating and lithogeochemical studies have been performed on the Xianggou monzonitic granitic porphyry outcropped in the Ma'anqiao gold deposit.A weighted average U-Pb age of 242.0±0.8 Ma for Xianggou monzonitic porphyry has been *** corresponds with the conclusions of previous studies indicating a syn-orogenic age (242±21 Ma) of the Qinling Orogenic Belt,suggesting that the formation of the Xianggou granite should be associated with the collisional event of the North china Plate and the Yangtze Plate in the Indosinian *** Xianggou granite is characterized by the high silicon and alkali of high K calc-alkaline series *** is rich in Al (Al2O3=14.49%-15.61%) and Sr (457.10-630.82 ppm),poor in Y (ctionated REE *** geochemical characteristics suggest the Xianggou granite can be classified as c-type adakitic *** initial Sr isotope ratios for the Xianggou granite vary from 0.70642 to 0.70668,εNd(t) values from -4.54 to -3.98,and TDM values from 1152 Ma to 1220 *** low εNd(t) and ISr and high TDM values,as well as Na2O/K2O ratios of the Xianggou granite are close to 1 (Na2O/K2O=0.95-1.10),indicating that it is not an I-type adakite formed by partial melting of the subducting oceanic crust,nor adakitic rock formed by melting of the underplated basaltic lower crust,but the product of partial melting of the nonunderplated basaltic thickened lower *** from the Xianggou pluton have a homogeneous Hf isotopic composition with negative εHf(t) values (between -9.7 and -5.9,with an average of -6.9),indicating that the rock-forming materials were mostly extracted from the ancient crust,not from the depleted *** Xianggou monzonitic granitic porphyry is rich in LILE and LREE and depleted in HSFE,HREE and Y;the composition of trace element and REE are similar to those of th

关键词： zircon U-Pb dating Xianggou monzonitic granitic porphyry carlin type and carlin-like type gold deposits petrologenic and metallogenic dynamic background

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Memory-enhanced noiseless cross-phase modulation

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Light(Science & Applications) 2012年第1期1卷 6-10页

作者： Mahdi Hosseini Stojan Rebic ben M Sparkes Jason Twamley ben c Buchler Ping K Lam centre for Quantum computation and communication Technology Department of Quantum ScienceThe Australian National UniversityCanberraAustralia centre for Engineered Quantum Systems Department of Physics&AstronomyMacquarie UniversityNorth Ryde NSW 2109Australia

Large nonlinearity at the single-photon level can pave the way for the implementation of universal quantum ***,realizing large and noiseless nonlinearity at such low light levels has been a great challenge for scientists in the past ***,we propose a scheme that enables substantial nonlinear interaction between two light fields that are both stored in an atomic *** and quantum simulations demonstrate the feasibility of achieving large cross-phase modulation(XPM)down to the single-photon *** proposed scheme can be used to implement parity gates from which cNOT gates can be ***,we present a proof of principle experimental demonstration of XPM between two optical pulses:one stored and one freely propagating through the memory medium.

关键词： cNOT gate cross-phase modulation electromagnetically induced transparency parity gate quantum memory

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淤泥改性土力学强度研究

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公路工程 2024年第3期49卷 162-169页

作者：陈建民胡杰吴帅峰刘奔刘峥嵘湖南省交通规划勘察设计院有限公司湖南长沙410200 湖南省衡永高速公路建设开发有限公司湖南长沙410004

道路工程中淤泥资源化利用是目前存在的技术难题,为此将淤泥改性成路基填料,以SM-c型改性剂对淤泥改性土的性能影响为研究主体,进行击实试验、无侧限抗压强度试验和cBR试验分析淤泥改性土力学性能的演变规律,进行干湿循环试验研究改性... 详细信息

道路工程中淤泥资源化利用是目前存在的技术难题,为此将淤泥改性成路基填料,以SM-c型改性剂对淤泥改性土的性能影响为研究主体,进行击实试验、无侧限抗压强度试验和cBR试验分析淤泥改性土力学性能的演变规律,进行干湿循环试验研究改性土抵抗水损坏的能力,进行微观试验研究淤泥改性土的改性机理。研究成果如下:①随改性剂掺量增加,改性土最佳含水率提高,最大干密度下降。②添加改性剂能显著提升淤泥改性土的无侧限抗压强度、cBR值,8%掺量的淤泥改性土可满足各等级道路路基填料cBR值要求。③随改性剂掺量的增加,淤泥改性土水稳性能提升明显。④微观试验结果表明,改性剂拌合淤泥发生水化反应,生成的碳酸钙及水化硅酸钙等水化产物填充在颗粒孔隙间,使土颗粒粒径增加,土体力学强度得到提升。

关键词：路基工程淤泥改性土力学强度改性机理固废利用

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基于完形填空的方面级情感四元组预测

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计算机学报 2024年第8期47卷 1744-1768页

作者：彭文忠夏家莉万齐智刘德喜万本庭曹重华夏池玉江西财经大学信息管理学院南昌330032 江西财经大学软件与物联网工程学院南昌330032 江西财经大学财经数据科学重点实验室南昌330013 江西财经大学数据与知识工程江西省高校重点实验室南昌330013

方面情感四元组预测(ASQP)任务旨在从给定的评论语句中提取所有方面词以及相应的方面类别、观点表达和情感极性,有助于全面了解用户对产品或服务不同方面的评价情况.现有情感四元组预测方法主要存在以下局限:(1)判别式模型没有利用promp... 详细信息

方面情感四元组预测(ASQP)任务旨在从给定的评论语句中提取所有方面词以及相应的方面类别、观点表达和情感极性,有助于全面了解用户对产品或服务不同方面的评价情况.现有情感四元组预测方法主要存在以下局限:(1)判别式模型没有利用prompt捕获情感元素之间的语义关系;(2)生成式模型要么简单地将情感元素类型标签组合形成prompt,缺乏理解标签类型涵义的语境;要么将离散模板作为解码器的输入,而编码器则无法捕获到模板中情感元素之间的语义关系.为了缓解这些问题,本文首先基于完形填空思想研制离散和连续2类prompt,提供理解4个情感元素类型涵义的语境,帮助模型更好地捕获情感元素之间的语义关系;然后,基于设计的prompt,提出c-ASQP框架,包含判别式模型Dc-ASQP和生成式模型Gc-ASQP.在Dc-ASQP中,采用2阶段策略,先预测4个情感元素中2个较为容易的情感元素,再将预测结果嵌入到设计的prompt中,帮助模型理解情感元素类型的涵义,从而有效预测另外2个情感元素.在Gc-ASQP中,将设计的prompt作为编码器的输入,借助预训练模型的学习模式,充分利用预训练模型蕴含的知识提升四元组的生成效果.实验结果显示,Dc-ASQP模型在4个常用数据集上的F1值相比同类判别式最优模型分别提高4.70%、6.48%、6.97%和2.60%,Gc-ASQP模型的F1值比最优基准模型分别提高0.86%、1.67%、0.15%和1.02%,验证了将ASQP建模为完形填空任务的有效性,所设计的2类prompt以及c-ASQP框架是有效的.

关键词：方面情感四元组预测完形填空离散和连续prompt 判别式和生成式模型 c-ASQP框架

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Audit pricing and nature of controlling shareholders:Evidence from France

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china Journal of Accounting Research 2013年第1期6卷 21-34页

作者： chiraz ben Ali cdric Lesage IPAG Business School France HEc Paris France

This study examines whether auditors are employed as a monitoring mechanism to mitigate agency problems arising from different types of controlling shareholders. In a context of concentrated ownership and poor investor protection, controlling shareholders can easily expropriate wealth from minority shareholders and profit from private benefits of control. However, this agency conflict has been rarely studied, as the most commonly assumed agency conflict occurs between managers and shareholders. Using an audit fee model derived from Simunic(1980), we study the impact of the nature of controlling shareholders on audit fees in French listed firms. Our results show:(1) a negative relationship between audit fees and government shareholdings;(2) a positive relationship between audit fees and institutional shareholdings; and(3) no relationship between audit fees and family shareholdings. These results illustrate the mixed effects of the nature of ownership on audit fees.

关键词： Audit fees controlling shareholder identity Minori

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