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Heterogenization of a dinuclear Cobalt Molecular Catalyst in Porous Polymers via Covalent Strategy for CO_(2)Photoreduction with Record CO Production Efficiency

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CCS Chemistry 2024年第12期6卷 3030-3040页

作者： Yun-Nan Gong si-Ya Lv Hao-Yu Yang Wen-Jie Shi Jing-Jing Wang Long Jiang di-Chang Zhong Tong-Bu Lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384 Instrumental Analysis and Research Center Sun Yat-Sen UniversityGuangzhou 510275

Photocatalytic CO_(2)reduction into chemical fuels is a promising route for alleviating the energy crisis and environmental ***,reported catalysts still exhibit low catalytic efficiencies,which hinders the development of this important ***,we report the heterogenization of a dinuclear cobalt molecular catalyst into two porous polymers(Co_(2)-P1 and Co_(2)-P2)using a covalent strategy for photocatalytic CO_(2)*** a result,Co_(2)-P1 with a phenyl group as the linker exhibited high catalytic performance for the photochemical CO_(2)-to-CO conversion with a CO production rate of 568.8 mmol g-1 h-1 and turnover frequency(TOF)of 11.6 min-1(CO selectivity,95.2%).More impressively,by extending the phenyl to biphenyl linker,the resulting Co_(2)-P2 shows obviously enhanced photocatalytic efficiency for CO_(2)reduction to CO,with a record CO production rate of 1063.0 mmol g-1 h-1 and TOF of 23.6 min-1(CO selectivity,94.9%)under a laboratory light ***,Co_(2)-P2 also shows outstanding catalytic activity for photocatalytic CO_(2)reduction under natural sunlight,with a CO production rate of 544.1 mmol g-1 h-1 and TOF of 12.1 min-1(CO selectivity,97.2%).Systematic studies demonstrated that fast electron transfer from the photosensitizer to the catalyst greatly contributes to the superior catalytic activity of Co_(2)-P2.

关键词： molecular catalyst heterogenization covalent strategy polymer photocatalysis CO_(2)reduction

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Influences of Alloying Elements on Oxidation Behavior of Steels and Microstructure of Oxide Scales

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Journal of Iron and Steel Research International 2016年第3期23卷 231-237页

作者： Hui-bin WU di WANG Peng-cheng ZHANG Jin-ming LIANG Sheng LIU di TANG National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing

In order to figure out the oxidation behavior of steels during heating,five micro-alloyed steels were subjected to continuous and isothermal oxidation using the thermo gravimetric analyzer and the Gleeble-3500thermo-mechanical *** microstructure of oxide scales,especially the thickness fractions of Fe2O3,Fe3O4 and FeO layers,was analyzed using the scanning electron microscope（SEM）,electron probe microanalyzer（EPMA）and electron backscattered diffraction（EBSD）*** micro-alloyed steels containing alloying elements（si,Cr,Ni and Cu）show a higher oxidation resistance compared with the low carbon *** is found that alloying elements accumulated at scale/substrate interface during high temperature *** elements function in two ways in the oxidation of steels：one is enhancing the scale/substrate interface and consequently suppressing the blister of scales;and the other is impeding the outward diffusion of iron cations from substrate to scales,resulting in the decrease of oxidation *** the diffusion of iron cations is impeded,the thickness fractions of Fe2O3 and Fe3O4of micro-alloyed steels are more than those of low carbon steels.

关键词： micro-alloyed steel high temperature oxidation oxidation kinetics microstructure oxide scale

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Comparative study on electrocrystallization of calcium phosphate ceramics on commercially pure titanium and selective laser melting titanium

Comparative study on electrocrystallization of calcium phosp...

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中国化学会第二十次全国电化学大会

作者： Xuetong Sun Chunyu Zhang Jian Jin si di Center for Precision Engineering Guangzhou Institutes of Advanced Technology Chinese Academy of Sciences

Commercially pure titanium is widely used in the field of biomedical implants, such as dental and orthopedic implants, but there are still disadvantages, such as poor osseointegration and low wear resistance [1, 2]. Nevertheless, the production of highly complex CP-Ti parts, which could be used as bone substitutes or implants, is challenging due to the poor machinability.

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Effects of Holding Temperature for Austempering on Mechanical Properties of si-Mn TRIP Steel

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Journal of Iron and Steel Research International 2004年第6期11卷 40-44页

作者： LI Zhuang WU di Northeastern University Shenyang Institute of Aeronautical Engineering

A new type of high strength steel containing a significant amount of stable retained austenite was obtained by austempering immediately after intercritical *** sort of low carbon steel only contains alloying elements of silicon and manganese rather than nickel and *** mechanical properties were enhanced considerably due to strain-induced martensite transformation and transformation-induced plasticity(TRIP)of retained austenite when it was strained at temperatures between Msand Md,because retained austenite was moderately stabilized due to carbon enrichment by *** was carried out at different temperatures and 400 ℃ was found to be *** strength,total elongation and strength-ductility balance reached the maximum values and the product of tensile strength and total elongation exceeded 30 135 MPa % when the TRIP steel was held at 400 ℃ and strained at 350 ℃.

关键词： austempering intercritical annealing retained austenite strain-induced martensite transformation transformation-induced plasticity(TRIP) mechanical property

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土石坝渗流安全监测的遗传支持向量机方法

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水利学报 2007年第11期38卷 1341-1346页

作者：司春棣练继建郑杨天津大学建筑工程学院天津300072

为了有效地根据土石坝地原型观测资料来分析坝体和坝基中存在的渗流问题,本文在对建模因子进行分析的基础上,充分利用支持向量机的结构风险最小化原则和遗传算法快速全局优化的特点,通过支持向量机模型对非线性监测数据进行拟合,并利用... 详细信息

为了有效地根据土石坝地原型观测资料来分析坝体和坝基中存在的渗流问题,本文在对建模因子进行分析的基础上,充分利用支持向量机的结构风险最小化原则和遗传算法快速全局优化的特点,通过支持向量机模型对非线性监测数据进行拟合,并利用遗传算法优化支持向量机的模型参数,建立了基于GA-SVM的土石坝渗流监测模型。实例分析表明,该模型与传统的多元线性回归模型和神经网络模型相比,具有预测精度高、泛化能力强等优点,对土石坝安全监控具有实用价值。

关键词：土石坝渗流安全监测支持向量机遗传算法

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Chemical constituents from Gnaphalium affine and their xanthine oxidase inhibitory activity

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Chinese Journal of Natural Medicines 2018年第5期16卷 347-353页

作者： ZHANG Wei WU Chun-Zhen FAN si-Yang Department of Traditional Chinese Medicine Shanghai Institute of Pharmaceutical Industry Innovation Center of Traditional Chinese Medicine China State Institute of Pharmaceutical Industry sinopharm Health Industry Research Co. Ltd.

Gnaphalium affine D. Don, a medicinal and edible plant, has been used to treat gout in traditional Chinese medicine and popularly consumed in China for a long time. A detailed phytochemical investigation on the aerial part of G. affine led to the isolation of two new esters of caffeoylquinic acid named(-) ethyl 1, 4-di-O-caffeoylquinate(1) and(-) methyl 1, 4-di-O-caffeoylquinate(2), together with 35 known compounds(3-37). Their structures were elucidated by spectroscopic data and first-order multiplet analysis. All the isolated compounds were tested for their xanthine oxidase inhibitory activity with an in vitro enzyme inhibitory screening assay. Among the tested compounds, 1(IC_(50) 11.94 μmol·L^(-1)) and 2(IC_(50) 15.04 μmol·L^(-1)) showed a good inhibitory activity. The current results supported the medical use of the plant.

关键词： Gnaphalium affine Compositae Caffeoylquinate Flavonoid Xanthine oxidase inhibition

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核磁共振波谱查询数据库

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波谱学杂志 2007年第2期24卷 119-123页

作者：谢狄霖陈忠邓思珊福建省医学测试重点实验室(福建省医学科学研究所) 福建福州350001 厦门大学物理系和化学系福建厦门361005

介绍了核磁共振波谱信息查询系统的程序设计和应用方法.系统数据库包含化合物核磁共振氢谱6万多张,核磁共振碳谱4万多张.可通过光谱编号、原子数、分子式进行查询,结果得到所要查询化合物的有关信息及其标准谱图.系统程序还允许用户将... 详细信息

介绍了核磁共振波谱信息查询系统的程序设计和应用方法.系统数据库包含化合物核磁共振氢谱6万多张,核磁共振碳谱4万多张.可通过光谱编号、原子数、分子式进行查询,结果得到所要查询化合物的有关信息及其标准谱图.系统程序还允许用户将本研究领域一些常用化合物的标准谱信息和图谱添加进数据库以供日后查询.

关键词：核磁共振波谱数据库查询

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Reliable resource allocation with RF fingerprinting authentication in secure IoT networks

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Science China(Information Sciences) 2022年第7期65卷 51-66页

作者： Weiwei WU Su HU di LIN Gang WU National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China

The unprecedented growth of the Internet of Things(Io T) has led to a huge amount of wireless resource consumption in a network. Due to limited wireless resources, a network can only guarantee the quality of service(QoS) of authenticated users rather than that of all users. By acknowledging this limitation,we realise that user authentication would be a big issue in Io T networks. Although traditional authentication methods can enhance network security to a certain extent, their vulnerability to malicious attacks and the relevant complicated computations restrict Io T deployments. In this paper, a radio frequency(RF)fingerprinting based authentication scheme is proposed under the architecture of convolutional neural network(CNN). It can effectively prevent unauthenticated users from consuming valuable wireless resources and significantly improve QoS performance for legitimate users. By solving an NP-hard optimization problem with the objective of minimizing efficient energy density, we demonstrate an approximate optimal resource allocation scheme in consideration of an RF-fingerprinting based authentication process. The analytic results show that our proposed scheme can dramatically reduce the efficient energy density compared with traditional cryptography based authentication schemes.

关键词： user authentication Internet of things convolutional neural network RF fingerprinting NP-hard optimization problem

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基于情感从属和最大熵模型的细粒度观点挖掘

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计算机工程与科学 2015年第10期37卷 1952-1958页

作者：马长林谢罗迪司琪王梦华中师范大学计算机学院湖北武汉430079

目前许多观点挖掘方法挖掘粒度过大,导致反馈信息不足。为解决该问题,对标准LDA模型进行改进,提出主题情感联合最大熵LDA模型进行细粒度观点挖掘。首先,考虑到词的位置和语义信息,在传统LDA模型中加入最大熵组件来区分背景词、特征词和... 详细信息

目前许多观点挖掘方法挖掘粒度过大,导致反馈信息不足。为解决该问题,对标准LDA模型进行改进,提出主题情感联合最大熵LDA模型进行细粒度观点挖掘。首先,考虑到词的位置和语义信息,在传统LDA模型中加入最大熵组件来区分背景词、特征词和观点词,并对特征词和观点词进行局部和全局的划分;其次,在主题层和单词层之间加入情感层,实现词语级别的细粒度情感分析,并引入情感转移变量来处理情感从属关系,同时获取整篇评论和每个主题的情感极性,实验验证了所提模型和理论的有效性。

关键词： LDA模型细粒度观点挖掘最大熵情感从属

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Comparative study between swept-source and spectraldomain OCTA for imaging of choroidal neovascularization in age-related macular degeneration

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International Journal of Ophthalmology(English edition) 2024年第11期17卷 2067-2073页

作者： Ji-Xian Ma Zhuo-Yi Zhang Rong di Jia-Jie Yang si-Wen Tian Ya-Zhou Qin Wan-Hu Zhang Jian-Qin Lei Qiu-Ping Liu Jing-Ming Li Department of Ophthalmology the First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina Affiliated Eye Hospital of Nanchang University Nanchang 330006Jiangxi ProvinceChina Department of Ophthalmology First Affiliated Hospital of Nanhua UniversityHengyang 421005Hunan ProvinceChina

AIM:To compare the dif ferences of choroidal neovascularization(CNV)measurements between sweptsource and spectral-domain optical coherence tomography angiography(SS-OCTA and SD-OCTA)in neovascular agerelated macular degeneration(nAMD)and the imaging reliability of the two ***:Prospective comparative ***-OCTA and SD-OCTA were used to scan the same eye with the modes of 3×3 and 6×6 mm2 centered on the *** qualified images were chosen and the border of CNV was manually delineated by two graders *** area of CNV(ACNV),vascular perfusion density(PD),and vessel length density(VLD)within the delineation were calculated using Image *** differences of CNV measurements between the two OCTA devices were compared using Bland-Altman *** agreement between the two graders on the measurements of each device was compared using the intraclass correlation coefficient(ICC).RESULTS:A total of 18 patients(22 eyes)with nAMD were *** measurements of ACNV,PD,and VLD were 7.247±4.586 and 4.901±3.741 mm^(2),43.202±9.636 and 34.904±10.489,6.339±1.228 and 5.908±1.741 mm^(-1) for SS-OCTA and SD-OCTA,*** differences between the two devices were 2.346±3.030 mm^(2)(Z=-3.782,Psignal strength.

关键词： neovascular age-related macular degeneration swept-source spectral-domain optical coherence tomography angiography

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