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广东率先基本实现现代化要走多化协调发展之途
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作者 张长生 《岭南学刊》 2002年第6期73-76,共4页
广东率先基本实现现代化 ,要走多化协调之途包括有 :一是以人的现代化为中心目标 ,促进经济现代化、政治现代化、文化现代化和人的现代化的协调发展 ;二是以增创市场化优势为前提 ,促进经济体制与生产力的协调发展 ;三是以信息化为先导 ... 广东率先基本实现现代化 ,要走多化协调之途包括有 :一是以人的现代化为中心目标 ,促进经济现代化、政治现代化、文化现代化和人的现代化的协调发展 ;二是以增创市场化优势为前提 ,促进经济体制与生产力的协调发展 ;三是以信息化为先导 ,促进生产力内部诸化的协调发展 ;四是以区域协调发展为方向 ,促进区域诸化的协调发展。 展开更多
关键词 广东 现代 多化协调发展 经济发展战略
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多化×二化蚕茧煮茧的研究:加压煮茧对缫丝和质量性状的影响(英文) 被引量:3
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作者 G.Hariraj T.H.Somashekar 《蚕业科学》 CAS CSCD 2003年第4期391-398,共8页
对印度多化、二化松驰结构的蚕茧进行了压力煮茧的研究。实验按照正交排列布局L 2 7方法设计。研究了浸渍温度和时间 ,蒸汽渗透时间 ,水渗透时间和煮茧时间对丝质性状的影响。发现浸渍温度与废物率和洁净之间有密切关系 ,而浸渍时间与... 对印度多化、二化松驰结构的蚕茧进行了压力煮茧的研究。实验按照正交排列布局L 2 7方法设计。研究了浸渍温度和时间 ,蒸汽渗透时间 ,水渗透时间和煮茧时间对丝质性状的影响。发现浸渍温度与废物率和洁净之间有密切关系 ,而浸渍时间与清洁百分率和拉伸率有显著相关 ;蒸汽渗透时间与解舒丝长、生丝率、清洁和生丝的抱合有显著相关 ,对生丝强力有显著影响 ;煮茧时间对生丝的清洁性状有重要影响。研究表明 ,经热空气干燥的多化、二化蚕茧能有效地用高压 (压力 )煮茧 。 展开更多
关键词 多化×二 蚕茧 压力煮茧 浸渍 温度 蒸汽渗透 水渗透 丝质性状 清洁百分率 拉伸率
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“一题多化”探析
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作者 董玉亮 《辽宁师专学报(自然科学版)》 2000年第4期34-35,共2页
如何引导学生利用灵活、准确的手法解答物理习题 ,帮助学生巩固加深所学理论 ,发展学生逻辑和综合思维能力以及提高举一反三的能力 ,“一题多化”
关键词 “一题多化 磨擦力 平衡状态 物理习题 物理教学 逻辑思维能力 教学方法
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化工部要求认真搞好“管理年”活动总结
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《化工管理》 1996年第12期37-37,共1页
最近,化工部向各省、自治区、直辖市、计划单列市、化工厅(局、公司)发出“认真搞好‘管理年’活动总结的通知”,通知指出: 今年以来,在化工部统一部署下,全国化工系统认真开展了“管理年”活动。各级化工管理部门对这项活动都很重视,... 最近,化工部向各省、自治区、直辖市、计划单列市、化工厅(局、公司)发出“认真搞好‘管理年’活动总结的通知”,通知指出: 今年以来,在化工部统一部署下,全国化工系统认真开展了“管理年”活动。各级化工管理部门对这项活动都很重视,进行了具体的安排。许多化工企业结合“学吉化。 展开更多
关键词 管理年 工部 管理部门 完成指标 企业结合 计划单列 通知 完成情况 多化 工系统
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浅论施工企业“多化”管理的缺失、成因及对策
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作者 周全 《铁道工程企业管理》 2011年第5期15-17,共3页
随着市场激烈的竞争和企业自身发展的需要,施工企业积极适应形势,果断采取措施,明确提出了以"管理标准化、结构科学化、布局合理化、经营市场化、技术现代化、生产工厂化、队伍专业化、考核精细化"(以下简称"多化"... 随着市场激烈的竞争和企业自身发展的需要,施工企业积极适应形势,果断采取措施,明确提出了以"管理标准化、结构科学化、布局合理化、经营市场化、技术现代化、生产工厂化、队伍专业化、考核精细化"(以下简称"多化")为精髓的新的管理理念,以应对日益激烈的行业竞争。"多化"管理的最终要义, 展开更多
关键词 施工企业 多化 管理措施 技术现代 管理理念 项目经理 缺失 对策 成因 工程项目
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Conjugated microporous polymers-scaffolded enzyme cascade systems with enhanced catalytic activity
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作者 Zhenhua Wu Jiafu Shi +6 位作者 Boyu Zhang Yushuai Jiao Xiangxuan Meng Ziyi Chu Yu Chen Yiran Cheng Zhongyi Jiang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期213-223,共11页
Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs... Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2)) is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2) interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling. 展开更多
关键词 BIOCATALYSIS IMMOBILIZATION Enzyme cascade system Substrate channeling effect Conjugated microporous polymers
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气液驱替法提高燃料电池输出功率初探 被引量:4
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作者 徐献芝 《自然杂志》 北大核心 2001年第4期214-217,共4页
本文介绍了多孔电极的一种新的工作方式 ,在周期性的压力作用下 ,通过气液两相在多孔电极内的驱替运动 ,在多孔电极内表面形成有利于气体参与反应的三相界面 ,并促进反应物的补充和生成物的排泄 ,使电极能在高电流密度下工作 ,最终提高... 本文介绍了多孔电极的一种新的工作方式 ,在周期性的压力作用下 ,通过气液两相在多孔电极内的驱替运动 ,在多孔电极内表面形成有利于气体参与反应的三相界面 ,并促进反应物的补充和生成物的排泄 ,使电极能在高电流密度下工作 ,最终提高燃料电池单位体积的输出功率 . 展开更多
关键词 气液驱替法 气体电极 燃料电池 两相渗流 比表面 输出功率 多化电极
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Ab initio molecular dynamics simulation reveals the influence of entropy effect on Co@BEA zeolite-catalyzed dehydrogenation of ethane
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作者 Yumeng Fo Shaojia Song +8 位作者 Kun Yang Xiangyang Ji Luyuan Yang Liusai Huang Xinyu Chen Xueqiu Wu Jian Liu Zhen Zhao Weiyu Song 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期195-205,共11页
The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate.To understand the impact of entropy,we performed ab initio static and molecular dynamics free energy simulati... The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate.To understand the impact of entropy,we performed ab initio static and molecular dynamics free energy simulations of ethane dehydrogenation over Co@BEA zeolite at different temperatures.AIMD simulations showed that a sharp decrease in free energy barrier as temperature increased.Our analysis of the temperature dependence of activation free energies uncovered an unusual entropic effect accompanying the reaction.The unique spatial structures around the Co active site at different temperatures influenced both the extent of charge transfer in the transition state and the arrangement of 3d orbital energy levels.We provided explanations consistent with the principles of thermodynamics and statistical physics.The insights gained at the atomic level have offered a fresh interpretation of the intricate long-range interplay between local chemical reactions and extensive chemical environments. 展开更多
关键词 Ethane dehydrogenation C-H bond activation Ab initio molecular dynamics simulation ENTROPY Heterogeneous catalysis
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Research on the Mechanism of Multi-Sensor Fusion Configuration Based on the Optimal Principle of the Vehicle
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作者 Zhao Binggen Zeng Dong +2 位作者 Lin Haoyu Qiu Xubo Hu Pijie 《汽车技术》 CSCD 北大核心 2024年第10期28-37,共10页
In order to address the issue of sensor configuration redundancy in intelligent driving,this paper constructs a multi-objective optimization model that considers cost,coverage ability,and perception performance.And th... In order to address the issue of sensor configuration redundancy in intelligent driving,this paper constructs a multi-objective optimization model that considers cost,coverage ability,and perception performance.And then,combining a specific set of parameters,the NSGA-II algorithm is used to solve the multi-objective model established in this paper,and a Pareto front containing 24 typical configuration schemes is extracted after considering empirical constraints.Finally,using the decision preference method proposed in this paper that combines subjective and objective factors,decision scores are calculated and ranked for various configuration schemes from both cost and performance preferences.The research results indicate that the multi-objective optimization model established in this paper can screen and optimize various configuration schemes from the optimal principle of the vehicle,and the optimized configuration schemes can be quantitatively ranked to obtain the decision results for the vehicle under different preference tendencies. 展开更多
关键词 Multi-sensor fusion Intelligent driving Multi-objective optimization Vehicle optimization
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SOX2/DRD2 signaling pathway facilitates astrocytic dedifferentiation in cerebral ischemic mice
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作者 YI Xuyang KANG Enming +4 位作者 WANG Yanjin ZHANG Kun LIN Wei WU Shengxi WANG Yazhou 《神经解剖学杂志》 CAS CSCD 北大核心 2024年第3期277-286,共10页
Objective:To explore the effects of dopamine receptor D2(DRD2)on astrocytic dedifferentiation based on SOX2-regulated genes in neural stem cells(NSCs)and astrocytes.Methods:Immunofluorescence staining and SOX2-GFP mic... Objective:To explore the effects of dopamine receptor D2(DRD2)on astrocytic dedifferentiation based on SOX2-regulated genes in neural stem cells(NSCs)and astrocytes.Methods:Immunofluorescence staining and SOX2-GFP mice were used to examine the lineage differentiation of SOX2-positive cells during the development of cerebral cortex.Primary NSCs/astrocytes culture,ChIP-seq and Western Blot were adopted to analyze and verify the expression of candidate genes.Pharmacological manipulation,neurosphere formation,photochemical ischemia,immunofluorescence staining and behavior tests were adopted to evaluate the effects of activating DRD2 signaling on astrocytic dedifferentiation.Results:Immunofluorescence staining demonstrated the NSC-astrocyte switch of SOX2-expression in the normal development of cerebral cortex.ChIP-seq revealed enrichment of DRD2 signaling by SOX2-bound enhancers in NSCs and SOX2-bound promoters in astrocytes.Western Blot and immunofluorescence staining verified the expression of DRD2 in NSCs and reactive astrocytes.Application of quinagolide hydrocholoride(QH),an agonist of DRD2,significantly promoted astrocytic dedifferentiation both in vitro and in vivo following ischemia.In addition,quinagolide hydrocholoride treatment improved locomotion recovery.Conclusion:Activating DRD2 signaling facilitates astrocytic dedifferentiation and may be used to treat ischemic stroke. 展开更多
关键词 cerebral ischemia ASTROCYTE DEDIFFERENTIATION SOX2 dopamine D2 receptor(DRD2) mouse
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In-situ building of multiscale porous NiFeZn/NiZn-Ni heterojunction for superior overall water splitting
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作者 Ya-xin LI Hong-xiao YANG +4 位作者 Qiu-ping ZHANG Tian-zhen JIAN Wen-qing MA Cai-xia XU Qiu-xia ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2972-2986,共15页
The development of efficient nonprecious bifunctional electrocatalysts for water electrolysis is crucial to enhance the sluggish kinetics of the oxygen evolution reaction(OER)and hydrogen evolution reaction(HER).A sel... The development of efficient nonprecious bifunctional electrocatalysts for water electrolysis is crucial to enhance the sluggish kinetics of the oxygen evolution reaction(OER)and hydrogen evolution reaction(HER).A self-supporting,multiscale porous NiFeZn/NiZn-Ni catalyst with a triple interface heterojunction on nickel foam(NF)(NiFeZn/NiZn-Ni/NF)was in-situ fabricated using an electroplating-annealing-etching strategy.The unique multiinterface engineering and three-dimensional porous scaffold significantly modify the mass transport and electron interaction,resulting in superior bifunctional electrocatalytic performance for water splitting.The NiFeZn/NiZn-Ni/NF catalyst demonstrates low overpotentials of 187 m V for HER and 320 mV for OER at a current density of 600 mA/cm^(2),along with high durability over 150 h in alkaline solution.Furthermore,an electrolytic cell assembled with NiFeZn/NiZn-Ni/NF as both the cathode and anode achieves the current densities of 600 and 1000 m A/cm^(2) at cell voltages of 1.796 and 1.901 V,respectively,maintaining the high stability at 50 mA/cm^(2) for over 100 h.These findings highlight the potential of NiFeZn/NiZn-Ni/NF as a cost-effective and highly efficient bifunctional electrocatalyst for overall water splitting. 展开更多
关键词 NiFeZn alloy multiple interface porous structure DEALLOYING overall water splitting
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Enhancing zinc storage performance of Mn_(3)O_(4)cathode through Ag-doping and-crosslinking dual-modification strategy
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作者 Xin-yuan WANG Tian-zhen JIAN +5 位作者 Ya-ting YANG Jian-ping MA Xian-hong LI Zi-long XUE Wen-qing MA Cai-xia XU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第11期3693-3706,共14页
Octahedral Mn_(3)O_(4)nanoparticles with an Ag-doping and nanoporous Ag(NPS)framework was simply fabricated through an alloying-etching engineering.The dual-modified Mn_(3)O_(4)(denoted as Ag−Mn_(3)O_(4)/NPS)consists ... Octahedral Mn_(3)O_(4)nanoparticles with an Ag-doping and nanoporous Ag(NPS)framework was simply fabricated through an alloying-etching engineering.The dual-modified Mn_(3)O_(4)(denoted as Ag−Mn_(3)O_(4)/NPS)consists of Ag-doped Mn_(3)O_(4)nanoparticles crosslinked with three dimensional nanoporous Ag framework.The incorporated Ag dopant is effective in improving the intrinsic ionic and electronic conductivities of Mn_(3)O_(4),while the NPS framework is introduced to improve the electron/mass transfer across the entire electrode.Profiting from the dual-modification strategy,the Ag−Mn_(3)O_(4)/NPS exhibits admirable rate capability and cycling stability.A high reversible capacity of 88.7 mA·h/g can still be retained for over 1000 cycles at a current density of 1 A/g.Moreover,a series of ex-situ experimental techniques indicate that for Ag−Mn_(3)O_(4)/NPS electrode during the zinc ion storage,Mn_(3)O_(4)is electrochemically oxidized into various MnOx(e.g.,Mn_(2)O_(3),MnO2)species in the initial charging,and the subsequent battery reaction is actually the intercalation/deintercalation of H+and Zn2+into MnOx. 展开更多
关键词 Ag-doped Mn_(3)O_(4) zinc ion battery nanoporous Ag DEALLOYING
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Catalytically altering the redox pathway of sulfur in propylene carbonate electrolyte using dual-nitrogen/oxygen-containing carbon
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作者 Linghui Yu Heng Zhang +9 位作者 Luyuan Paul Wang Samuel Jun Hoong Ong Shibo Xi Bo Chen Rui Guo Ting Wang Yonghua Du Wei Chen Ovadia Lev Zhichuan J.Xu 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期224-233,共10页
Carbonate electrolytes are one of the most desirable electrolytes for high-energy lithium-sulfur batteries(LSBs)because of their successful implementation in commercial Li-ion batteries.The low-polysulfide-solubility ... Carbonate electrolytes are one of the most desirable electrolytes for high-energy lithium-sulfur batteries(LSBs)because of their successful implementation in commercial Li-ion batteries.The low-polysulfide-solubility feature of some carbonate solvents also makes them very promising for overcoming the shuttle effects of LSBs.However,regular sulfur electrodes experience undesired electrochemical mechanisms in carbonate electrolytes due to side reactions.In this study,we report a catalytic redox mechanism of sulfur in propylene carbonate(PC)electrolyte based on a compari-son study.The catalytic mechanism is characterized by the interactions between polysulfides and dual N/O functional groups on the host carbon,which largely prevents side reactions between polysulfides and the carbonate electrolyte.Such a mechanism coupled with the low-polysulfide-solubility feature leads to stable cycling of LSBs in PC electrolyte.Favorable dual N/O functional groups are identified via a density functional theory study.This work provides an alternative route for enabling LSBs in carbonate electrolytes. 展开更多
关键词 Energy storage Lithium-sulfur battery Catalytic redox reaction Porous carbon Carbonate electrolyte
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对中国高校影视艺术教育现状的思考 被引量:5
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作者 邓进 《电影评介》 2011年第7期66-68,71,共4页
影视艺术的发展直接影响着社会的进步与精神文明的建设,也影响着民族思想文化的集中与传统文化的传承。高校影视艺术教育在办学主体多元化的"功利性"因素驱动下呈现空前繁荣的假象,导致影视艺术人才培养被泛化等一系列问题,... 影视艺术的发展直接影响着社会的进步与精神文明的建设,也影响着民族思想文化的集中与传统文化的传承。高校影视艺术教育在办学主体多元化的"功利性"因素驱动下呈现空前繁荣的假象,导致影视艺术人才培养被泛化等一系列问题,我们必须通过对现象的反思与分析,全面探讨影视艺术教育的发展模式,才能实现影视艺术教育的和谐均衡发展,推动社会的进步与精神文明的建设。 展开更多
关键词 影视艺术教育 多化 商业 功利
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High-resolution reconstruction of the ablative RT instability flowfield via convolutional neural networks
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作者 Xia Zhiyang Kuang Yuanyuan +1 位作者 Lu Yan Yang Ming 《强激光与粒子束》 CAS CSCD 北大核心 2024年第12期42-49,共8页
High-resolution flow field data has important applications in meteorology,aerospace engineering,high-energy physics and other fields.Experiments and numerical simulations are two main ways to obtain high-resolution fl... High-resolution flow field data has important applications in meteorology,aerospace engineering,high-energy physics and other fields.Experiments and numerical simulations are two main ways to obtain high-resolution flow field data,while the high experiment cost and computing resources for simulation hinder the specificanalysis of flow field evolution.With the development of deep learning technology,convolutional neural networks areused to achieve high-resolution reconstruction of the flow field.In this paper,an ordinary convolutional neuralnetwork and a multi-time-path convolutional neural network are established for the ablative Rayleigh-Taylorinstability.These two methods can reconstruct the high-resolution flow field in just a few seconds,and further greatlyenrich the application of high-resolution reconstruction technology in fluid instability.Compared with the ordinaryconvolutional neural network,the multi-time-path convolutional neural network model has smaller error and canrestore more details of the flow field.The influence of low-resolution flow field data obtained by the two poolingmethods on the convolutional neural networks model is also discussed. 展开更多
关键词 convolutional neural networks ablative Rayleigh-Taylor instability high-resolutionreconstruction multi-time-path pooling
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Oxidation behavior of RE-modified nickel-based superalloy between 950℃ and 1150℃ in air 被引量:8
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作者 刘龙飞 吴树森 +1 位作者 陈阳 吕书林 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1163-1169,共7页
A new Ni-based superalloy Ni48Cr28W5Co3Mn1Si1.6 was developed and the influence of a trace amount of rare earth (RE) metal addition on the oxidation resistance of this alloy was investigated. Isothermal oxidation beha... A new Ni-based superalloy Ni48Cr28W5Co3Mn1Si1.6 was developed and the influence of a trace amount of rare earth (RE) metal addition on the oxidation resistance of this alloy was investigated. Isothermal oxidation behavior was investigated at 950?1150 °C in air, and then analyzed using scanning electronic microscopy and X-ray diffraction. The results showed that oxidation mass gain kinetics of the samples with and without RE elements follow the parabolic law. The effect of 0.20% RE on oxidation resistance is relatively small, and the oxidation rate constant of the alloy modified with 0.20% RE addition decreases by 5.9%?9.0%. Oxidation at 950?1150 °C for 100 h results in the formation of MnCr2O4, Cr2O3 and SiO2. A continuous and protective MnCr2O4 spinel layer forms as outer layer. The continuous middle oxide layer is confirmed to be Cr2O3, and the innermost layer consists of discontinuous SiO2. 展开更多
关键词 Ni-based superalloy rare earth element high temperature oxidation multi-layered oxides
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A fracture enhancement method based on the histogram equalization of eigenstructure-based coherence 被引量:7
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作者 窦喜英 韩立国 +3 位作者 王恩利 董雪华 杨庆 鄢高韩 《Applied Geophysics》 SCIE CSCD 2014年第2期179-185,253,共8页
Eigenstructure-based coherence attributes are efficient and mature techniques for large-scale fracture detection. However, in horizontally bedded and continuous strata, buried fractures in high grayscale value zones a... Eigenstructure-based coherence attributes are efficient and mature techniques for large-scale fracture detection. However, in horizontally bedded and continuous strata, buried fractures in high grayscale value zones are difficult to detect. Furthermore, middleand small-scale fractures in fractured zones where migration image energies are usually not concentrated perfectly are also hard to detect because of the fuzzy, clouded shadows owing to low grayscale values. A new fracture enhancement method combined with histogram equalization is proposed to solve these problems. With this method, the contrast between discontinuities and background in coherence images is increased, linear structures are highlighted by stepwise adjustment of the threshold of the coherence image, and fractures are detected at different scales. Application of the method shows that it can also improve fracture cognition and accuracy. 展开更多
关键词 FAULT FRACTURE histogram equalization COHERENCE ENHANCEMENT
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New immune multiobjective optimization algorithm and its application in boiler combustion optimization 被引量:4
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作者 周霞 沈炯 +1 位作者 沈剑贤 李益国 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期563-568,共6页
In order to meet the requirements of combustion optimization for saving energy and reducing pollutant emission simultaneously,an immune cell subsets based multiobjective optimization algorithm(ICSMOA)is proposed.In ... In order to meet the requirements of combustion optimization for saving energy and reducing pollutant emission simultaneously,an immune cell subsets based multiobjective optimization algorithm(ICSMOA)is proposed.In the ICSMOA,the subset division operator and the immunological tolerance operation are defined.Preference can be easily addressed by using the subset division operator,and the distribution of the solutions can be guaranteed by the immunological tolerance operation.Using the ICSMOA,a group of Pareto optimal solutions can be obtained.However,by the traditional weighting method(WM),only one solution can be obtained and it cannot be judged as Pareto optimal or not.In contrast to the solutions obtained by the repeatedly performed WM,the simulation results show that most solutions obtained by the ICSMOA are better than the solutions obtained by the WM.In addition,the Pareto front obtained by the ICSMOA is not as uniform as most classical multiobjective optimization algorithms.More optimal solutions which meet the preference set by the decision-maker can be obtained and they are very useful for industrial application. 展开更多
关键词 combustion optimization multiobjective optimizat-ion immune cell subsets
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Anti-oxidation Activity in Vitro of Polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme 被引量:30
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作者 汪曙 魏凤娟 +1 位作者 蔡永萍 林毅 《Agricultural Science & Technology》 CAS 2009年第6期121-124,共4页
[ Objective ] The aim was to study the effects of polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme on oxygen free radicals and lipid peroxidation in vitro. [ Method] The scavenging action on .OH of... [ Objective ] The aim was to study the effects of polysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme on oxygen free radicals and lipid peroxidation in vitro. [ Method] The scavenging action on .OH of polysaccharides, the inhibition action on O2^- of polysaccharides, MDA production of lipid peroxidation were measured by Fenton reaction, self oxidation system of C6H3( OH)3 and TBA method respectively. [ Result] The half scavenging concentration on ·OH of potysaccharides of Dendrobium Huoshanense and Dendrobium moniliforme was 6.79 and 6.75 mg/ml respectively. As to their half inhibition concentration on O2 , the data was 3, 04 and 3.44 mg/ml respectively. Two kinds of Dendrobium polysaccharides bothhad inhibitory actions on lipid peroxidation of liver homogenate induced by auto-oxidation and inducedoxidation, and they could alleviate oxidation damages of mice liver mitochondria induced by Vc-Fe2+ system. [Conclusion] Two kinds of Dendrobium polysacchaddes both had remarkable anti-oxidation activity in vitro. 展开更多
关键词 Dendrobium Huoshanense Dendrobium moniliforme Lipid peroxidation .OH O2^- POLYSACCHARIDES
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The Role of Polyamine Oxidative Degradation in the Process of Lettuce Seed Germination 被引量:5
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作者 王立伟 孙娜 +1 位作者 张凤芝 苏国兴 《Agricultural Science & Technology》 CAS 2010年第1期86-89,共4页
[Objective]The aim of this study was to understand the role of polyamine oxidative degradation in the process of lettuce seed germination. [Method]After lettuce seed soaking treatments with aminoguanidine (AG,a speci... [Objective]The aim of this study was to understand the role of polyamine oxidative degradation in the process of lettuce seed germination. [Method]After lettuce seed soaking treatments with aminoguanidine (AG,a specific inhibitor of polyamine oxidases),seed germination rate,activities of polyamine oxidase (PAO) and diamine oxidase (DAO),change of endogenous polyamine and H2O2 content were determined. [Result]Compared with the control,AG treatment strongly inhibited the seed germination,which also had an extremely significant difference in seed germination rate after incubation for 12 h. During the seed germination,activities of PAO and DAO significantly changed,while their activities firstly increased and then decreased,then DAO and PAO reached peaks at 24 h and 48 h respectively. AG treatment was strongly inhibitory for activities of DAO and PAO,whose activities even disappeared after incubation with AG for 24 h and 36 h. During the seed germination,endogenous Put reduced sharply in the first 24 h,then reduced slowly in 24-60 h,while Spd decreased slowly in the early stage of germination,and then sharply declined after 48 h. However,Spm content was low but slightly increased,and the total polyamine gradually decreased. AG treatment could significantly increase endogenous polyamines,especially Put and Spd contents. During the seed germination,H2O2 content gradually increased,and had a peak from 36 to 48 h,then kept a high level at last. AG treatment could significantly reduce H2O2 content. [Conclusion]During the seed germination,the changes of endogenous polyamine and H2O2 content correspond with the changes of PAO and DAO activities,which indicate that there is an active polyamine metabolism of oxidative degradation during the lettuce seed germination. 展开更多
关键词 LETTUCE Seed germination Polyamine degradation Polyamine oxidases
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