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Chinese Chemical Letters 2006年第8期17卷 1061-1064页

作者： Wen long zhang Yan mei WANG Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026

Quasi-interpenetrating network formed by polyacrylamide and poly （N-hydroxymethylacrylamide） was designed, synthesized, and tested for DNA sequencing by capillary electrophoresis. The performance of quasi-IPN on DNA... 详细信息

关键词： Capillary electrophoresis DNA sequencing quasi-interpenetrating network.

食品检测实验室数字化转型和物联网技术应用标准化的探讨

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中国标准化 2024年第9期 183-187页

作者：巩泽龙杨悦严烨屠锦娣彭辉李丁一张美龙西安市质量与标准化研究院西安悟空检测科技有限公司陕西科仪阳光检测技术服务有限公司西安中检科测试认证技术有限公司

为提升食品检测实验室数字化水平,加快信息化建设,将物联网技术应用到传统实验室流程中,在采样阶段、受理阶段、检测阶段、报告阶段及实验室安全的关键环节,通过USB、RS 232、LAN、WIFI、GPRS等扩展接口将检测仪器、监测设备和智能终端... 详细信息

为提升食品检测实验室数字化水平,加快信息化建设,将物联网技术应用到传统实验室流程中,在采样阶段、受理阶段、检测阶段、报告阶段及实验室安全的关键环节,通过USB、RS 232、LAN、WIFI、GPRS等扩展接口将检测仪器、监测设备和智能终端同LIMS相结合,基于ADAS、Internet、RTSP、ONVIF、NLP等协议进行数据的传输和利用,构建食品检测实验室物联网系统。该系统降低了人员参与度,提高了数据安全性和准确性,实现实验室标准化规范管理流程,提升了管理水平和效率,保障实验室运行安全,为实验室数字化转型奠定了基础。

关键词：实验室数字化物联网标准化食品

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地理标志产品临潼石榴标准化发展研究

中国标准化 2024年第8期 97-100页

作者：张星刘欣刘志千聂娉舒惠蕙朱玉帆张美龙西安市质量与标准化研究院

本文以标准化为研究视角,梳理临潼石榴标准化现状,以及标准化对临潼石榴实现产业化发展、提升产品质量、促进区域经济效益的作用,分析当前面临标准体系不健全、标准化意识不强、标准实施应用率较低和标准信息化共享度较低等问题,提出建... 详细信息

本文以标准化为研究视角,梳理临潼石榴标准化现状,以及标准化对临潼石榴实现产业化发展、提升产品质量、促进区域经济效益的作用,分析当前面临标准体系不健全、标准化意识不强、标准实施应用率较低和标准信息化共享度较低等问题,提出建立健全标准体系,提高标准化意识,加强标准实施的监督检查,加快完善标准信息服务等对策建议,对完善临潼石榴标准化工作,促进产业发展具有一定的借鉴意义。

关键词：地理标志产品临潼石榴标准化

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Difluoromethyl phenoxathiinium salt: A new general and versatile difluoromethylating reagent with divergent ·CF_(2)H, CF_(2)H^(+), and :CF_(2) reactivities

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Science China Chemistry 2024年第3期67卷 953-962页

作者： Yuan-Qing Gu Hong-Xin long Dan-Dan zhang mei-Feng Ruan Guo-Kai Liu School of Pharmacy Shenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China

Development of practical and versatile electrophilic difluoromethylating reagent is still a grand challenge so far due to its inherent instability or low ***,we report the design and synthesis of difluoromethyl phenoxathiinium tetrafluoroborate(PT-CF_(2)H^(+)BF_(4)^(-)) as a novel difluoromethylating reagent,which proves to be a bench-stable,general,powerful and versatile reagent with divergent·CF_(2)H,CF_(2)H^(+),and:CF_(2) *** use of this reagent,we demonstrated a vast array of difluoromethyl radical transfer reactions via diverse pathways involving photocatalyst-free visible-light induction,visible-light photoredox catalysis and visible-light mediation single electron transfer of EDA ***,the green and highly effective CF_(2)H^(+) and:CF_(2) transfer reactions were also readily accomplished.

关键词： difluoromethyl phenoxathiinium salt versatile difluoromethylating reagent difluoromethyl radical difluoromthyl cation difluorocarbene

Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： zhang long ZHAO Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

True-temperature inversion algorithm for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization

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Nanotechnology and Precision Engineering 2024年第1期7卷 55-62页

作者： mei Liang Zhuo Sun Jiasong Liu Yongsheng Wang Lei Liang long zhang School of Electromechanical and Automotive Engineering Yantai UniversityYantai 264005China Liangshan Mining Co. Ltd.Huili 615141China

Herein,a method of true-temperature inversion for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization is proposed for difﬁcult inversion problems with unknown ***-order calculus has the inherent advantage of easily jumping out of local extreme values;here,it is introduced into the particle-swarm algorithm to invert the true *** improved adaptive-adjustment mechanism is applied to automatically adjust the current velocity order of the particles and update their velocity and position values,increasing the accuracy of the true temperature *** results of simulations using the proposed algorithm were compared with three algorithms using typical emissivity models:the internal penalty function algorithm,the optimization function(fmincon)algorithm,and the conventional particle-swarm optimization *** results show that the proposed algorithm has good accuracy for true-temperature *** experimental results from a rocket-motor plume were used to demonstrate that the true-temperature inversion results of this algorithm are in good agreement with the theoretical true-temperature values.

关键词： Fractional-order particle swarm True-temperature inversion algorithm Multi-wavelength pyrometer

Experimental Study on Wire Melting Control Ability of Twin-Body Plasma Arc

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 184-194页

作者： Ruiying zhang Fan Jiang long Xue School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Beijing Academy of Safety Engineering and Technology Beijing 102617China College of Mechanical and Energy Engineering Beijing University of TechnologyBeijing 100124China

The twin-body plasma arc has the decoupling control ability of heat transfer and mass transfer,which is beneficial to shape and property control in wire arc additive *** this paper,with the wire feeding speed as a characteristic quantity,the wire melting control ability of twin-body plasma arc was studied by adjusting the current separation ratio(under the condition of a constant total current),the wire current/main current and the position of the wire in the arc axial *** results showed that under the premise that the total current remains unchanged(100 A),as the current separation ratio increased,the middle and minimum melting amounts increased approximately synchronously under the effect of anode effect power,the first melting mass range remained constant;the maximum melting amount increased twice as fast as the middle melting amount under the effect of the wire feeding speed,and the second melting mass range was *** the wire current increased,the anode effect power and the plasma arc power were both factors causing the increase in the wire melting amount;however,when the main current increased,the plasma arc power was the only factor causing the increase in the wire melting *** average wire melting increment caused by the anode effect power was approximately 2.7 times that caused by the plasma arc *** minimum melting amount was not affected by the wire-torch distance under any current separation ratio *** the current separation ratio increased and reached a threshold,the middle melting amount remained constant with increasing wire-torch *** the current separation ratio continued to increase and reached the next threshold,the maximum melting amount remained constant with the increasing wire-torch *** effect of the wire-torch distance on the wire melting amount reduced with the increase in the current separation *** this study,the decoupling mechanism and ability of this innovative

关键词： Twin-body plasma arc Melting control ability Melting amount Current separation ratio

Chien-physics-informed neural networks for solving singularly perturbed boundary-layer problems

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1467-1480页

作者： long WANG Lei zhang Guowei HE The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

A physics-informed neural network(PINN)is a powerful tool for solving differential equations in solid and fluid ***,it suffers from singularly perturbed boundary-layer problems in which there exist sharp changes caused by a small perturbation parameter multiplying the highest-order *** this paper,we introduce Chien's composite expansion method into PINNs,and propose a novel architecture for the PINNs,namely,the Chien-PINN(C-PINN)*** novel PINN method is validated by singularly perturbed differential equations,and successfully solves the wellknown thin plate bending *** particular,no cumbersome matching conditions are needed for the C-PINN method,compared with the previous studies based on matched asymptotic expansions.

关键词： physics-informed neural network(PINN) singular perturbation boundarylayer problem composite asymptotic expansion

Characterizations of semihoops based on derivations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 291-310页

作者： WANG mei zhang Xiao-hong School of Electrical and Control Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Arts and Sciences Shaanxi University of Science and TechnologyXi'an 710021China School of Mathematics and Statistics Weinan Normal UniversityWeinan 714099China

In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of ***,we prove that every Heyting algebra is isomorphic to the algebra of all multiplicative derivations and show that every Boolean algebra is isomorphic to the algebra of all implicative ***,we show that the sets of multiplicative and implicative derivations on bounded regular idempotent semihoops are in oneto-one correspondence.

关键词： (prelinear)semihoop derivation Heyting algebra Galois connection

Study on carbon emission calculation method and carbon reduction indexes of urban building stock

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Science China(Technological Sciences) 2024年第9期67卷 2706-2726页

作者： YANG Liu zhang Nan LU mei LUO ZhiXing DOU mei State Key Laboratory of Green Building Xi’an University of Architecture and TechnologyXi’an 710055China School of Architecture Xi’an University of Architecture and TechnologyXi’an 710055China School of Language Literature and LawXi’an University of Architecture and TechnologyXi’an 710055China School of Management Xi’an University of Architecture and TechnologyXi’an 710055China China Southwest Architectural Design and Research Institute Corp.Ltd. Chengdu 610041China

Carbon emissions associated with buildings are a major source of urban emissions. To put forward the methods and strategies to curb carbon emissions from urban building stock, it is not only necessary to establish a carbon emission calculation method for fine statistical analysis, but also to evaluate carbon emissions of urban planning schemes with applicable indexes. Currently,researches mainly focus on carbon emissions of individual buildings. When expanded to urban building stock, the calculation faces the lack of basic data, inadequate spatial analysis and unspecific carbon reduction indexes. Therefore, this study proposes a bottom-up calculation method for urban building stock, conducts spatial analysis based on carbon balance of urban grids, reveals the coupling mechanism between urban carbon reduction indexes and grid carbon emissions, and systematically establishes a carbon-reduction-oriented urban planning method that comprises calculation, analysis and evaluation, which is applied to Xi'an,China. This study provides a theoretical reference for cities to formulate carbon reduction targets and implement planning strategies by evaluating and predicting carbon emissions from urban building stock.

关键词： carbon emissions urban building stock calculation method carbon reduction index