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HR分解的精化扰动界(英文)

Journal of Mathematical Study 2012年第3期45卷 263-270页

作者：赖降周卢琳璋福州大学数学与计算机科学学院贵州师范大学数学与计算机科学学院厦门大学数学科学学院

给出了HR分解的分量型和范数型的一阶扰动界.对于范数型,新的精化扰动界至少优于已有结果,特别的,新的关于R因子的扰动界远远优于已有的扰动界.

关键词：条件估值 HR分解扰动分析

A Study of the Times Planning of the Development of Tin Inlay Art in Weihai, China

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A Study of the Times Planning of the Development of Tin Inla...

4,4’-二甲氧基三苯胺取代偶氮苯开关分子的设计合成、电化学及光化学性质研究

作者： Xiaochen Geng Xiamen Academy of Arts and Design fuzhou university School of Fine Arts Nanjing Normal university

This paper analyzes the characteristics of the era of China's Weihai tin inlay art development. On the basis of a large number of relevant rationalization proposals, it integrates the Chinese Weihai tin inlay art, and reviews in more details from mining culture, introducing mechanism and cultural creative product development and other aspects. Finally, the characteristics of the era of China's Weihai tin inlay development were analyzed and summarized.

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有机化学 2019年第7期39卷 2009-2017页

作者：鄢剑锋张睿祺原野袁耀锋福州大学化学学院福州350116 中国科学院福建物质结构研究所结构化学国家重点实验室福州350002

通过Pd催化的Sonogashira偶联合成了三个以4,4'-二甲氧基三苯胺基团为氧化还原中心的偶氮苯化合物4~6,电化学和光谱电化学的研究表明,该类化合物具有优秀的氧化还原可逆性.光致异构的实验表明,三苯胺基团在偶氮苯上的取代位置对该类化... 详细信息

通过Pd催化的Sonogashira偶联合成了三个以4,4'-二甲氧基三苯胺基团为氧化还原中心的偶氮苯化合物4~6,电化学和光谱电化学的研究表明,该类化合物具有优秀的氧化还原可逆性.光致异构的实验表明,三苯胺基团在偶氮苯上的取代位置对该类化合物的光化学性质有显著的影响.化合物4不仅可以通过光照实现顺式到反式的异构化,也可仅通过改变三苯胺基团的价态高效地实现.

关键词：三苯胺偶氮苯光致异构氧化还原

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基于PSO-BP神经网络的双相不锈钢电弧增材制造焊道成形预测（英文）

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Journal of Marine Science and Application 2023年第2期 311-323页

作者：郑开魁姚传旭牟刚向红亮 School of Advanced Manufacturing Fuzhou University Fujian Science & Technology Innovation Laboratory for Optoelectronic Information School of Mechanical Engineering and Automation Fuzhou University

Duplex stainless steel was formed through welding wire and arc additive manufacturing(WAAM) using tungsten inert gas. The effects of wire feeding speed(WFS), welding speed(WS), welding current, and their interaction on the weld bead width and height were discussed. Back-propagation(BP) neural network algorithm prediction model was established by taking the bead width and height as the output layer, and the network weight and threshold values were optimized using the particle swarm optimization(PSO) algorithm to obtain the prediction model of bead width and height. The predicted results were verified by experiments. Results show that the weld bead width increases with the increase in WFS and the welding current and decreases with WS. The smaller the WFS, the faster the WS, which is beneficial for the generation of equiaxed crystals. The smaller the welding current, the faster the cooling speed of the metal melt, which is conducive to the formation of dendrites. The interaction among WS, wire feed speed, and welding current has a significant effect on the bead width. The weld bead height is positively correlated with the wire feed speed and negatively correlated with the WS and current. The interaction between the wire feed speed and WS is significant. The optimized WAAM process parameters for duplex stainless steel are a wire feed speed of 200 cm/min, WS of 24 cm/min, and welding current of 160 A. The maximum error of the BP neural network in predicting the weld bead width and height is 7.74%, and the maximum error between the predicted and experimental values of the BP-PSO neural network is 4.27%. This finding indicates that the convergence speed is fast, improving the prediction accuracy.

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V205纳米棒的软化学法合成

功能材料 2007年第A6期38卷 2266-2268页

作者：陈玉珍罗海燕高绍康江莉龙叶炳火魏明灯福州大学化学化工学院福建福州350002 福州大学新能源材料研究所福建福州350002 福州大学化肥催化剂工程研究中心福建福州350002

采用一种简单的软化学法制备出直径大约为50nm的V2O5纳米棒。此方法无需添加表面活性剂或催化剂，只使用原料和水。合成的产物经XRD、SEM、TEM、FT-IR等分析手段进行表征。另外基于实验结果，进一步提出了可能的形成机理。

关键词： V205 纳米棒软化学法形成机理

Sm-Fe GMFs的组织结构与静态磁致伸缩性能(英文)

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Sm-Fe GMFs的组织结构与静态磁致伸缩性能(英文)

Windows隔离用户FTP技术的应用研究与实现方案

第九届真空冶金与表面工程学术会议

作者：周白杨骆汉彬材料科学与工程学院

采用离子束溅射沉积(IBSD)、铸造合金靶材技术,在水冷金属衬底上溅射制备Sm-Fe超磁致伸缩薄膜材料(Sm-Fe GMFs);并对薄膜样品进行了不同温度的真空加热处理。结果表明:采用实验拟定的IBSD工艺可获得表面平整光滑、膜层组织均匀致密、与... 详细信息

采用离子束溅射沉积(IBSD)、铸造合金靶材技术,在水冷金属衬底上溅射制备Sm-Fe超磁致伸缩薄膜材料(Sm-Fe GMFs);并对薄膜样品进行了不同温度的真空加热处理。结果表明:采用实验拟定的IBSD工艺可获得表面平整光滑、膜层组织均匀致密、与衬底材料结合良好的非晶态Sm-FeGMFs,随加热温度升高,膜材组织结构发生了非晶→非晶+微晶→纳米多晶的转变过程(晶化温度约为400℃),其静态磁致伸缩性能也随之发生变化;经过适当温度的真空加热处理,能有效改善Sm-Fe膜材的静态磁致伸缩性能、大幅度提高其低场磁敏性(λ约为350×10-6)。

关键词： Sm-Fe GMFs 组织结构静态磁伸性能

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计算机光盘软件与应用 2011年第20期14卷 72-73页

作者：熊建辉陈琼亮余庚福州海峡职业技术学院福州350003 福建工程学院国脉信息学院福州350003 福州捷盈计算机技术有限公司福州350004

FTP技术在各行各业中应用广泛。方便了信息资源的共享和访问。但Windows中系统自带FTP功能一般被认为存在一定安全风险和不便之处，甚至被认为存在着功能缺陷。本文主要针对这一问题对工作组模式及域服务模式下隔离用户FTP技术进行应用... 详细信息

FTP技术在各行各业中应用广泛。方便了信息资源的共享和访问。但Windows中系统自带FTP功能一般被认为存在一定安全风险和不便之处，甚至被认为存在着功能缺陷。本文主要针对这一问题对工作组模式及域服务模式下隔离用户FTP技术进行应用研究，并给出具体解决方案。

关键词：隔离用户 FTP技术活动目录

Moisture Absorption and Diffusion of a Carbon Composite Structure

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Sustainable Marine Structures 2019年第2期1卷 12-18页

作者： Bing Wang School of Mechanical Engineering&Automation Fuzhou UniversityFuzhou 350108China

Composite materials are lightweight structures and have been wildly used in marine applications.A carbon composite structure usually absorbs moisture while in-service,which can significantly affect its properties,and detriments the overall *** perform a detailed study on moisture absorption and diffusion of a carbon fibre reinforced vinyl ester resin composite *** samples are immersed directly in four different solutions at a temperature of 37±0.5℃for *** moisture diffusion is analysed through the Fickian diffusion model;the diffusion parameters are subsequently determined from the gravimetric *** moisture absorption and interaction with the composite constituents are then *** indicate the fundamentals of the moisture absorption and diffusion within the carbon composite structure.

关键词： Composite Moisture Absorption Degradation Fickian diffusion

Preparation of guanidine-modified starch for antimicrobial paper

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Journal of Bioresources and Bioproducts 2016年第1期1卷 3-6页

作者： Kai Liu Xinxing Lin Lihui Chen Liulian Huang College of Material Engineering Fujian Agriculture and Forestry UniversityFuzhou 350002China

Normal paper does not have antimicrobial *** impart antimicrobial properties to paper for medical applications,a guanidine-modified starch was prepared via two reaction steps using guanidine hydrochloride(GH)as a modifier,and added to the paper coating ***-IR demonstrated that the GH was successfully grafted onto the starch via the Schiff base *** coating with the modified starch,the antimicrobial performance of the paper against *** and *** was evaluated by the disc diffusion *** results indicated that the paper treated with the guanidine-modified starch exhibited excellent antimicrobial properties against the *** and *** addition,the dry and wet strength indexes of the coated paper increased by 25%and 100%,respectively,as compared to the control paper.

关键词： Starch Guanidine hydrochloride Medical paper Antimicrobial activity Tensile strength