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STRONGLY CONVERGENT INERTIAL FORWARD-BACKWARD-FORWARD ALGORITHM WITHOUT ON-LINE RULE FOR VARIATIONAL INEQUALITIES
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作者 姚永红 Abubakar ADAMU Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期551-566,共16页
This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inerti... This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inertial parameters and the iterates,which have been assumed by several authors whenever a strongly convergent algorithm with an inertial extrapolation step is proposed for a variational inequality problem.Consequently,our proof arguments are different from what is obtainable in the relevant literature.Finally,we give numerical tests to confirm the theoretical analysis and show that our proposed algorithm is superior to related ones in the literature. 展开更多
关键词 forward-backward-forward algorithm inertial extrapolation variational inequality on-line rule
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Stylistic Analysis on English On-line Chat
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作者 别尽秋 闻扬波 《海外英语》 2013年第6X期224-225,227,共3页
Based on the fact that on-line chat has become the most developing language form in the information age, this article point out the stylistic features of on-line English chat. Though in written language form, such lan... Based on the fact that on-line chat has become the most developing language form in the information age, this article point out the stylistic features of on-line English chat. Though in written language form, such language is spoken language in nature, thus it is worthwhile to analyze this special phaenomenon in lexical and grammatical level. 展开更多
关键词 on-line ENGLISH STYLISTIC analysIS LEXICAL grammat
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One-step Eco-friendly Fabrication of Antibacterial Polyester Via On-line Amination Reaction by Melt Coextrusion
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作者 ZHANG Huan ZHAO Qinghua +4 位作者 ZHONG Yaping CAI Ruiyan LIU Ke WANG Dong LU Zhentan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第5期1205-1212,共8页
The work is dedicated to develop a one-step eco-friendly method to prepare antibacterial polyethylene terephthalate(PET).We report a one-step eco-friendly method to manufacture antibacterial PET via on-line amination ... The work is dedicated to develop a one-step eco-friendly method to prepare antibacterial polyethylene terephthalate(PET).We report a one-step eco-friendly method to manufacture antibacterial PET via on-line amination reaction by melt coextrusion.Beside evenly mixing of poly(hexamethylene guanidine)(PHMG)and PET in the melt coextrusion procedure,the amination reaction also occurred between PHMG and PET under high temperature(230-270℃).The antibacterial ability of composite PET showed obvious PHMG concentration dependence,and antibacterial activity reached more than 99%when PHMG content was 2.5 wt%.Moreover,LIVE/DEAD fluorescence test further confirmed that the composite PET could kill bacteria quickly and efiectively(within 30 min);while negligible cytotoxicity was observed to HSF and HUVEC cells.Onestep eco-friendly fabrication of composite antibacterial PET was accomplished by on-line melt coextrusion.The composite antibacterial PET has potential use in multiple fields to combat with pathogenic including textiles,packaging materials,decoration materials and biomedical devices,etc. 展开更多
关键词 antibacterial polyester one-step eco-friendly method on-line amination reaction melt coextrusion cytocompatibility
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Rapid analysis of fifteen sulfonamide residues in pork and fish samples by automated on-line solid phase extraction coupled to liquid chromatography–tandem mass spectrometry 被引量:6
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作者 Junmei Ma Sufang Fan +3 位作者 Lei Sun Liangna He Yan Zhang Qiang Li 《Food Science and Human Wellness》 SCIE 2020年第4期363-369,共7页
The aim of this work was to develop an automated on-line solid phase extraction(SPE)with liquid chromatography-tandem mass spectrometry method for the detection of fifteen sulfonamides in pork and fish samples.Samples... The aim of this work was to develop an automated on-line solid phase extraction(SPE)with liquid chromatography-tandem mass spectrometry method for the detection of fifteen sulfonamides in pork and fish samples.Samples were extracted with 0.2%formic acid acetonitrile solution,purified by on-line SPE device with HLB column,then separated by XBridge C18 column,using 0.1%formic acid solution and acetonitrile as the mobile phase.Mass spectrometric data was acquired under multiple reaction monitoring(MRM)mode using positive ionization electrospray.Internal standard method was used in the quantification,good linear relationship was got in range of 0.1–100 ng/mL and correlation coefficient was higher than 0.9990.The limits of detection were in the range of 0.125–2.00g/kg and the limits of quantitation were in the range of 0.250–5.00g/kg.Recoveries of the method were in range of 78.3%–99.3%,relative standard deviation were lower than 10%.The method was simple,sensitivity,and could be used for routine supervision and analysis of fifteen sulfonamides in pork and fish. 展开更多
关键词 Liquid chromatography–tandem mass SPECTROMETRY on-line solid phase extraction SULFONAMIDES Internal standard quantification
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Theory analysis and experimental research on on-line contamination detecting technology in hydraulic oil 被引量:1
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作者 姚成玉 赵静一 张齐生 《Journal of Coal Science & Engineering(China)》 2006年第1期115-118,共4页
A system of on-line contamination detecting in hydraulic oil based on silting principle is accomplished, where, metal filter membrane as detector, solenoid as active force to propel piston to blotter and gain differen... A system of on-line contamination detecting in hydraulic oil based on silting principle is accomplished, where, metal filter membrane as detector, solenoid as active force to propel piston to blotter and gain differential pressure, step motor drives the membrane to filtrate and counter-flush, LabVIEW as detecting software platform, oil's contamination detecting indirectly by gauging differential pressure. Based on theory analysis, accomplished is relation between contamination level and differential pressure, realizing polynomial curve fitting, and calibration experiment. Field experiment is simulated in the condition of experimental laboratory, has credible precision and real-time performance, which can popularize to the field of production. 展开更多
关键词 hydraulic oil on-line detecting silting principle
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Multi-scale Modeling and Finite Element Analyses of Thermal Conductivity of 3D C/SiC Composites Fabricating by Flexible-Oriented Woven Process
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作者 Zheng Sun Zhongde Shan +5 位作者 Hao Huang Dong Wang Wang Wang Jiale Liu Chenchen Tan Chaozhong Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期275-288,共14页
Thermal conductivity is one of the most significant criterion of three-dimensional carbon fiber-reinforced SiC matrix composites(3D C/SiC).Represent volume element(RVE)models of microscale,void/matrix and mesoscale pr... Thermal conductivity is one of the most significant criterion of three-dimensional carbon fiber-reinforced SiC matrix composites(3D C/SiC).Represent volume element(RVE)models of microscale,void/matrix and mesoscale proposed in this work are used to simulate the thermal conductivity behaviors of the 3D C/SiC composites.An entirely new process is introduced to weave the preform with three-dimensional orthogonal architecture.The 3D steady-state analysis step is created for assessing the thermal conductivity behaviors of the composites by applying periodic temperature boundary conditions.Three RVE models of cuboid,hexagonal and fiber random distribution are respectively developed to comparatively study the influence of fiber package pattern on the thermal conductivities at the microscale.Besides,the effect of void morphology on the thermal conductivity of the matrix is analyzed by the void/matrix models.The prediction results at the mesoscale correspond closely to the experimental values.The effect of the porosities and fiber volume fractions on the thermal conductivities is also taken into consideration.The multi-scale models mentioned in this paper can be used to predict the thermal conductivity behaviors of other composites with complex structures. 展开更多
关键词 3D C/SiC composites Finite element analyses Multi-scale modeling Thermal conductivity
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Design,preparation,application of advanced array structured materials and their action mechanism analyses for high performance lithium-sulfur batteries
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作者 Nanping Deng Xiaofan Feng +7 位作者 Yongbing Jin Zhaozhao Peng Yang Feng Ying Tian Yong Liu Lu Gao Weimin Kang Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期266-303,I0007,共39页
Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely comme... Lithium-sulfur battery(LSB)has brought much attention and concern because of high theoretical specific capacity and energy density as one of main competitors for next-generation energy storage systems.The widely commercial application and development of LSB is mainly hindered by serious“shuttle effect”of lithium polysulfides(Li PSs),slow reaction kinetics,notorious lithium dendrites,etc.In various structures of LSB materials,array structured materials,possessing the composition of ordered micro units with the same or similar characteristics of each unit,present excellent application potential for various secondary cells due to some merits such as immobilization of active substances,high specific surface area,appropriate pore sizes,easy modification of functional material surface,accommodated huge volume change,enough facilitated transportation for electrons/lithium ions,and special functional groups strongly adsorbing Li PSs.Thus many novel array structured materials are applied to battery for tackling thorny problems mentioned above.In this review,recent progresses and developments on array structured materials applied in LSBs including preparation ways,collaborative structural designs based on array structures,and action mechanism analyses in improving electrochemical performance and safety are summarized.Meanwhile,we also have detailed discussion for array structured materials in LSBs and constructed the structure-function relationships between array structured materials and battery performances.Lastly,some directions and prospects about preparation ways,functional modifications,and practical applications of array structured materials in LSBs are generalized.We hope the review can attract more researchers'attention and bring more studying on array structured materials for other secondary batteries including LSB. 展开更多
关键词 Array structured materials Preparation methods and structural designs Action mechanism analyses Advanced Li-S batteries Excellent electrochemical performances and safety
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In silico prospective analysis of the medicinal plants activity on the CagA oncoprotein from Helicobacter pylori
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作者 Rafaela Viana Vieira Gabrielle Caroline Peiter +2 位作者 Fabrício Freire de Melo Ana Carla Zarpelon-Schutz Kádima Nayara Teixeira 《World Journal of Clinical Oncology》 2024年第5期653-663,共11页
BACKGROUND Colonization with Helicobacter pylori(H.pylori)has a strong correlation with gastric cancer,and the virulence factor CagA is implicated in carcinogenesis.Studies have been conducted using medicinal plants w... BACKGROUND Colonization with Helicobacter pylori(H.pylori)has a strong correlation with gastric cancer,and the virulence factor CagA is implicated in carcinogenesis.Studies have been conducted using medicinal plants with the aim of eliminating the pathogen;however,the possibility of blocking H.pylori-induced cell differentiation to prevent the onset and/or progression of tumors has not been addressed.This type of study is expensive and time-consuming,requiring in vitro and/or in vivo tests,which can be solved using bioinformatics.Therefore,prospective computational analyses were conducted to assess the feasibility of interaction between phenolic compounds from medicinal plants and the CagA oncoprotein.AIM To perform a computational prospecting of the interactions between phenolic compounds from medicinal plants and the CagA oncoprotein of H.pylori.METHODS In this in silico study,the structures of the phenolic compounds(ligands)kaempferol,myricetin,quercetin,ponciretin(flavonoids),and chlorogenic acid(phenolic acid)were selected from the PubChem database.These phenolic compounds were chosen based on previous studies that suggested medicinal plants as non-drug treatments to eliminate H.pylori infection.The three-dimensional structure model of the CagA oncoprotein of H.pylori(receptor)was obtained through molecular modeling using computational tools from the I-Tasser platform,employing the threading methodology.The primary sequence of CagA was sourced from GenBank(BAK52797.1).A screening was conducted to identify binding sites in the structure of the CagA oncoprotein that could potentially interact with the ligands,utilizing the GRaSP online platform.Both the ligands and receptor were prepared for molecular docking using AutoDock Tools 4(ADT)software,and the simulations were carried out using a combination of ADT and AutoDock Vina v.1.2.0 software.Two sets of simulations were performed:One involving the central region of CagA with phenolic compounds,and another involving the carboxy-terminus region of CagA with phenolic compounds.The receptor-ligand complexes were then analyzed using PyMol and BIOVIA Discovery Studio software.RESULTS The structure model obtained for the CagA oncoprotein exhibited high quality(C-score=0.09)and was validated using parameters from the MolProbity platform.The GRaSP online platform identified 24 residues(phenylalanine and leucine)as potential binding sites on the CagA oncoprotein.Molecular docking simulations were conducted with the three-dimensional model of the CagA oncoprotein.No complexes were observed in the simulations between the carboxy-terminus region of CagA and the phenolic compounds;however,all phenolic compounds interacted with the central region of the oncoprotein.Phenolic compounds and CagA exhibited significant affinity energy(-7.9 to-9.1 kcal/mol):CagA/kaempferol formed 28 chemical bonds,CagA/myricetin formed 18 chemical bonds,CagA/quercetin formed 16 chemical bonds,CagA/ponciretin formed 13 chemical bonds,and CagA/chlorogenic acid formed 17 chemical bonds.Although none of the phenolic compounds directly bound to the amino acid residues of the K-Xn-R-X-R membrane binding motif,all of them bound to residues,mostly positively or negatively charged,located near this region.CONCLUSION In silico,the tested phenolic compounds formed stable complexes with CagA.Therefore,they could be tested in vitro and/or in vivo to validate the findings,and to assess interference in CagA/cellular target interactions and in the oncogenic differentiation of gastric cells. 展开更多
关键词 CagA oncoprotein Phenolic compounds Helicobacter pylori In silico analyses Medicinal plants Prospective analysis
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Analysis and Application of the Synthetic Relative Measuring Method in On-Line Monitoring for Capacitive Equipment in Power Systems
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作者 Qing Guo Li-Jun Qin Hua-Wei Jin 《Journal of Electronic Science and Technology》 CAS 2011年第3期270-277,共8页
On-line measurement for dielectric loss angle can effectively monitor the insulation condition of capacitive equipment in power systems. Synthetic relative measuring methods not only markedly overcome the shortcomings... On-line measurement for dielectric loss angle can effectively monitor the insulation condition of capacitive equipment in power systems. Synthetic relative measuring methods not only markedly overcome the shortcomings of traditional absolute measuring methods but also greatly improve the accuracy of dielectric loss angle measurement. However, synthetic relative measuring methods based on two or three pieces of capacitive equipment do not have the characteristic of generality. In this paper, a principle of synthetic relative measuring method is presented. The example of application for synthetic relative methods based on three and four pieces of capacitive equipment running in the same phase is taken to present the failure judgment matrices for N pieces of equipment. According to these matrices, the fault condition of N pieces of capacitive equipment can be watched, which is more general. Then some problems needing to be concerned along with two diagnostic methods used in diagnostic system are introduced. Finally, two programmable flow charts for the two methods are given and corresponding examples demonstrate their feasibility in practice. 展开更多
关键词 Index Terms-Capacitive equipment dielectric loss angle on-line monitoring synthetic relative measuring method failure judgment matrix.
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Seismic Assessment of Asymmetric Structures Behaviour by Using Static Non-linear Analysis
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作者 Ivana Marino Luigi Petti 《Journal of Civil Engineering and Architecture》 2011年第5期402-411,共10页
The goal of this work is to investigate the seismic behaviour of plan-asymmetric structures by considering the least seismic-resistant directions and the spatial features of the seismic event. New tools for the analys... The goal of this work is to investigate the seismic behaviour of plan-asymmetric structures by considering the least seismic-resistant directions and the spatial features of the seismic event. New tools for the analysis of the seismic behaviour of plan-asymmetric structures are herein presented and the concepts of "Polar Spectrum" and limit domains are discussed. In particular, the capacity of the structure is described by using the limit domains based on the Non Linear Static Procedures, while the seismic demand is analysed by introducing a new representation of the spectral response. This representation is based on the construction of a spectral surface obtained by the spectral seismic response for different in-plan directions and the in-plan projection of this surface is herein defined "Polar Spectrum". The obtained results for two benchmark structures, verified by means of non-linear incremental dynamic analyses, have pointed out that non-linear static analyses, carried out for different in-plan directions of the incoming seismic action, have allowed us to accurately evaluate the least seismic resistant directions. 展开更多
关键词 Plan-asymmetric structures non-linear analyses polar spectrum.
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On-line Batch Process Monitoring and Diagnosing Based on Fisher Discriminant Analysis
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作者 赵旭 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第3期307-312,316,共7页
A new on-line batch process monitoring and diagnosing approach based on Fisher discriminant analysis (FDA) was proposed. This method does not need to predict the future observations of variables, so it is more sensi... A new on-line batch process monitoring and diagnosing approach based on Fisher discriminant analysis (FDA) was proposed. This method does not need to predict the future observations of variables, so it is more sensitive to fault detection and stronger implement for monitoring. In order to improve the monitoring performance, the variables trajectories of batch process are separated into several blocks. The key to the proposed approach for on-line monitoring is to calculate the distance of block data that project to low-dimension Fisher space between new batch and reference batch. Comparing the distance with the predefine threshold, it can be considered whether the batch process is normal or abnormal. Fault diagnosis is performed based on the weights in fault direction calculated by FDA. The proposed method was applied to the simulation model of fed-batch penicillin fermentation and the resuits were compared with those obtained using MPCA. The simulation results clearly show that the on-line monitoring method based on FDA is more efficient than the MPCA. 展开更多
关键词 batch process on-line process monitoring fault diagnosis Fisher discriminant analysis (FDA) multiway principal component analysis (MPCA)
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Mechanics Analysis of Overhead Transmission Lines Based On-line Monitoring
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作者 Lili Dai Yongli Zhu Zehui Liang 《Open Journal of Applied Sciences》 2013年第2期1-4,共4页
At present, the on-line monitoring is widely applied to the power line monitoring. In this paper, a new mechanical calculation model is established according to the on-line monitoring. And this model is based on the p... At present, the on-line monitoring is widely applied to the power line monitoring. In this paper, a new mechanical calculation model is established according to the on-line monitoring. And this model is based on the parameters that tension sensors and angle sensors on suspended points detect, and combines with the parameters of the wire itself, and also considers the deflection angel of wires due to wind. In this model, mechanics parameters of wires are turned into the new coordinate plane after deflection angel of wires due to wind, or windage yaw plane. A statics tension balance equation is built in the vertical direction of the new windage yaw plane. According to the theoretical analysis and algorithm, we verify the accuracy of this newly developed mechanical calculation model. 展开更多
关键词 OVERHEAD Transmission Line on-line Monitoring Mechanical analysIS Tension ANGLE ICING Windage Yaw
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Multi-Sensor Intelligent System for On-Line and Real-Time Moneitoring Tool Cutting State in FMS 被引量:1
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作者 徐春广 王信义 +1 位作者 邢济收 杨大勇 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期258-266,共9页
The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sens... The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sensor (AE) with motor current sensor was presented. The parallel communication between control system of machine tools, the monitoring intelligent system,and several decision-making systems for identifying tool cutting state was established It can auto - matically select the sensor way ,monitoring mode and identifying method in machining process- ing so as to build a successful and effective intelligent system for on -line and real-time moni- toring cutting tool states in FMS. 展开更多
关键词 tool cutting state on-line monitoring intelligent system acoustic emission sensor
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On-line机行血液透析滤过两种稀释模式效果的临床观察 被引量:2
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作者 易铁钢 祁爱蓉 程淑碧 《中国血液净化》 2004年第1期41-42,47,共3页
关键词 on-line 血液透析滤过 稀释模式 HDF 治疗 血液净化
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On-line hemodiafiltration技术和临床应用 被引量:25
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作者 谢红浪 季大玺 《肾脏病与透析肾移植杂志》 CAS CSCD 2005年第4期377-381,共5页
关键词 血液净化 肾脏疾病 临床 on-line 临床应用 肾脏替代治疗 终末期肾脏疾病 血液透析滤过 常规血液透析 生物相容性
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On-line血液透析滤过对移植肾功能延迟恢复的影响 被引量:1
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作者 余权星 刘强 +2 位作者 杜艺 李宓 彭莉 《中国血液净化》 2004年第4期192-193,200,共3页
目的 研究On -line血液透析滤过 (HDF)在移植肾功能延迟恢复患者中的应用。方法 我院2 0 0 2年 1月至 2 0 0 3年 7月肾移植术后发生移植肾功能延迟恢复患者 38例 ,2 9例采用Freseniuson -lineHDF透析机 ,F6 0透析器 ,透析滤过时间 3~... 目的 研究On -line血液透析滤过 (HDF)在移植肾功能延迟恢复患者中的应用。方法 我院2 0 0 2年 1月至 2 0 0 3年 7月肾移植术后发生移植肾功能延迟恢复患者 38例 ,2 9例采用Freseniuson -lineHDF透析机 ,F6 0透析器 ,透析滤过时间 3~ 4h ,血流量在 180~ 2 5 0ml/min ,置换液采取前稀释法 ,9例行HD治疗 ,采用GambroAK2 0 0透析机 ,F7透析器。结果  38例移植肾功能延迟恢复患者 ,2 9例用联机血液透析滤过 ,平均肾功能恢复时间为 ( 11.2± 5 .6 )天 ,治疗期间收缩压变化在 110~ 170mmHg,透析期间低血压发生率为 2 .6 % ,9例HD治疗者平均肾功能恢复时间为 ( 2 2 .3± 15 .7)天 ,透析期间低血压发生率为 13.2 %。结论 与HD比较 ,On -lineHDF对血压影响较小 ,可缩短移植肾功能恢复的时间。 展开更多
关键词 on-line血液透析 肾功能 肾移植 HDF
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Development and Application of On-Line Corrosion Monitoring Device for Condenser Tube 被引量:1
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作者 曹杰玉 宋敬霞 +2 位作者 汪德良 龙国军 孙本达 《Electricity》 2004年第2期31-35,共5页
This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current te... This paper introduces the development and industrial application of an on-line corrosion monitoring device for condenser tubes. Corrosion sensors are made up of representative condenser tubes chosen by eddy current test, which enable the monitoring result to be consistent with the corrosion of actual condenser tubes. Localized corrosion rate of condenser tubes can be measured indirectly by a galvanic couple made up of tube segments with and without pits. Using this technology, corrosion problems can be found in time and accurately, and anticorrosive measures be made more economic and effective. Applications in two power plants showed the corrosion measurements are fast and accurate. 展开更多
关键词 condenser tube CORROSION on-line monitoring INSTRUMENTATION
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平行机的实时到达on-line算法下界的改进 被引量:1
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作者 陈仕平 姚恩瑜 《高校应用数学学报(A辑)》 CSCD 北大核心 1999年第3期315-318,共4页
本文考虑了平行机实时到达的在线问题.模型中,工件是陆续到达的,工件的个数、到达时间是事先未知的,而且只有当工件到达,才知其加工时间,目标是使所有工件都加工完的时间达到最小.Chen与Vestjens(1996年)证明... 本文考虑了平行机实时到达的在线问题.模型中,工件是陆续到达的,工件的个数、到达时间是事先未知的,而且只有当工件到达,才知其加工时间,目标是使所有工件都加工完的时间达到最小.Chen与Vestjens(1996年)证明了该在线问题不存在性能比小于1.3473的on-line算法.本文将此界改进为(5-5)/2. 展开更多
关键词 排序 on-line算法 平行机 组合最优化 实时到达
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Effects of on-line solution and off-line heat treatment on microstructure and hardness of die-cast AZ91D alloy 被引量:1
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作者 徐玉磊 张奎 +3 位作者 李兴刚 雷健 袁海波 刘正 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2652-2658,共7页
The effects of on-line solution, off-line solution and aging heat treatment on the microstructure and hardness of the die-cast AZ91D alloys were investigated. Brinell hardness of die-cast AZ91D alloy increases through... The effects of on-line solution, off-line solution and aging heat treatment on the microstructure and hardness of the die-cast AZ91D alloys were investigated. Brinell hardness of die-cast AZ91D alloy increases through on-line solution and off-line aging treatment but decreases after off-line solution treatment. By X-ray diffractometry, optical microscopy, differential thermal analysis, scanning electron microscopy and X-ray energy dispersive spectroscopy, it is found that the microstructures of the die-cast AZ91D magnesium alloy before and after on-line solution and off-line aging are similar, consisting of α-Mg and β-Al12Mg17. The precipitation of Al element is prevented by on-line solution so that the effect of solid solution strengthening is enhanced. The β-Al12Mg17 phases precipitate from supersaturated Mg solid solution after off-line aging treatment, and lead to microstructure refinement of AZ91D alloy, so the effect of precipitation hardening is enhanced. The β-Al12Mg17 phases dissolve in the substructure after off-line solution treatment, which leads to that the grain boundary strengthening phase is reduced significantly and the hardness of die cast AZ91D is reduced. 展开更多
关键词 die-cast magnesium alloy AZ91D alloy on-line solution off-line solution treatment aging treatment β-Al12Mg17 phases microstructure refinement precipitation hardening
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On-line血液透析滤过对维持性血液透析患者心率变异性的影响 被引量:5
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作者 侯丹丹 王淑领 尚赛男 《临床和实验医学杂志》 2017年第17期1761-1764,共4页
目的探讨On-line血液透析滤过技术对维持性血液透析患者心率变异性(HRV)的影响。方法 50例维持性血液透析(MHD)患者随机分为常规血液透析治疗组(HD组)和On-line血液透析滤过治疗组(OL-HDF组),每组各25例。患者每周行3次、每次4 h的血液... 目的探讨On-line血液透析滤过技术对维持性血液透析患者心率变异性(HRV)的影响。方法 50例维持性血液透析(MHD)患者随机分为常规血液透析治疗组(HD组)和On-line血液透析滤过治疗组(OL-HDF组),每组各25例。患者每周行3次、每次4 h的血液透析治疗或OL-HDF,治疗24个月。比较两组常规的实验室检查和24h动态心电图监测结果。结果治疗24个月后,OL-HDF组的β2-微球蛋白(β2-MG)由基线值30.1±7.2 mg/dl降至21.7±6.1 mg/dl(P<0.05),HD组的β2-MG则无明显下降。OL-HDF组HRV的时域性和频域性指标均值高于基线值(P<0.05),HD组的HRV指标则无显著性变化(P>0.05)。结论与普通血液透析比较,OL-HDF能更好地改善MHD患者的HRV,改善自主神经功能。 展开更多
关键词 维持性血液透析 on-line血液透析滤过心率变异性
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