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固定边界布图规划；修正的模拟退火算法；全局搜索；溢出面积模型；B*-tree表示法 1

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Short-term effects of excessive anaerobic reaction time on anaerobic metabolism of denitrifying polyphosphate

Gang GUO, Yayi WANG, Chong WANG, Hong WANG, Mianli PAN, Shaowei CHEN

《环境科学与工程前沿（英文）》 2013年第7卷第4期页码 616-624 doi: 10.1007/s11783-013-0505-4

摘要： The short-term effect of anaerobic reaction time (AnRT) (i.e., 90, 120 and 150 min) on the denitrifying phosphorus (P) removal performance and N O production was examined using a denitrifying enhanced biologic phosphorus removal (EBPR) sludge acclimatized with mixed acetate (HAc) and propionate (Pro) (in the molar ratio 3∶1) as carbon sources. The results showed that when the AnRT was prolonged from 90 to 150 min, the anaerobic polyhydroxyalkanoate (PHA) synthesis was decreased by 15.3%. Moreover, the ineffective PHA consumption occurred in anaerobic phases and contributed to an increased accumulation and higher free nitrous acid (FNA) concentrations (≥0.001–0.0011 mg HNO -N/L) in the subsequent anoxic phases, causing a severe inhibition on anoxic P-uptake and denitrification. Accordingly, the total nitrogen (TN) and total phosphorus (TP) removal efficiencies dropped by approximately 6.3% and 85.5%, respectively; and the ratio of anoxic N O-N production to TN removal increased by approximately 3.8%. The fluorescence in situ hybridization (FISH) analysis revealed that the sludge was mainly dominated by (62.0% (SE = 1.5%)). In conclusion, the short-term excessive anaerobic reaction time negatively impacted denitrifying P removal performance and stimulated more N O production, and its effect on P removal was more obvious than that on nitrogen removal.

关键词： Denitrifying phosphorus removal anaerobic reaction time nitrous oxide polyhydroxyalkanoate free nitrous acid fluorescence in-situ hybridization

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Analysis of load transfer stability control strategy in hydraulic synchronized continuous slippage

LIU Yan-bo, WU Jian-zhong, ZHANG Xuan

《机械工程前沿（英文）》 2006年第1卷第2期页码 222-226 doi: 10.1007/s11465-006-0007-1

摘要： Hydraulic synchronized continuous slippage technique, which integrates mechanical, electrical and hydraulic control, is introduced in this paper for the practical requirements of some construction projects. The core of this technique (the stability of the load transfer) is illustrated in detail. Three speed control strategies to transfer the load excessive, lower and same speed are presented to accomplish the smoothness and stability in the process of slippage. An optimization of the speed control strategy (same speed) is deduced from the modeling analysis and its validity and maneuverability are tested by practical application, which provides evidence for similar engineering in theory and practice.

关键词： excessive slippage technique optimization continuous slippage engineering

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Fluid damping clearance in a control valve of injector

ZHANG Jianming, ZHANG Weigang, YANG Bing, WANG Yawei

《机械工程前沿（英文）》 2007年第2卷第4期页码 439-441 doi: 10.1007/s11465-007-0075-x

摘要： A force model of a control valve of injector is set up, and the changes of the fluid damping clearance are investigated on the basis of the results of the computational fluid dynamics (CFD) and the experiments of control valve of injector. Results indicate that a damping clearance of 0.02–0.03 mm between the poppet and the valve guide is the most sufficient to dampen any excessive control valve poppet bouncing.

关键词： control computational bouncing CFD excessive control

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Effects of EGR on combustion process of DI diesel engine during cold start

PENG Haiyong, CUI Yi, SHI Lei, DENG Kangyao

《能源前沿（英文）》 2008年第2卷第2期页码 202-210 doi: 10.1007/s11708-008-0038-x

摘要： Experiments on the effects of external and internal exhaust gas recirculation (EGR) on combustion and emission performance during a cold start process were investigated in a 135 single-cylinder DI diesel engine. Combustion was improved during the initial ignition cycles by introducing internal or external EGR. The addition of an appropriate amount of internal or external EGR can promote the combustion stability significantly. However, excessive amounts of external EGR could lead to extremely unstable combustion or even misfiring. An appropriate amount of internal or external EGR decreased smoke opacity effectively during a cold start. External EGR reduced NO emissions effectively while internal EGR led to an increase in NO emissions due to thermal effects.

关键词： opacity combustion excessive NO process

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Control concept and countermeasures for shallow lakes' eutrophication in China

JIN Xiangcan, LU Shaoyong, HU Xiaozhen, JIANG Xia, WU Fengchang

《环境科学与工程前沿（英文）》 2008年第2卷第3期页码 257-266 doi: 10.1007/s11783-008-0063-3

摘要： Research on lake eutrophication in China began in the early 1970s, and many lakes in China are now known to be in meso-eutrophic status. Lake eutrophication has been showing a rapidly increasing trend since 2000. Investigations show that the main reasons for lake eutrophication include a fragile lake background environment, excessive nutrient loading into lakes, excessive human activities, ecological degeneration, weak environmental protection awareness, and lax lake management. Major mechanisms resulting from lake eutrophication include nutrient recycling imbalance, major changes in water chemistry (pH, oxygen, and carbon), lake ecosystem imbalance, and algal prevalence in lakes. Some concepts for controlling eutrophication should be persistently proposed, including lake catchment control, combination of pollutant source control with ecological restoration, protection of three important aspects (terrestrial ecology, lake coast zone, and submerged plant), and combination of lake management with regulation. Measures to control lake eutrophication should include pollution source control (i.e., optimize industrial structural adjustments in the lake catchment, reduce nitrogen and phosphorus emission amounts, and control endogenous pollution) and lake ecological restoration (i.e. establish a zone-lake buffer region and lakeside zone, protect regional vegetation, utilize hydrophytes in renovation technology); countermeasures for lake management should include implementing water quality management, identifying environmental and lake water goals, legislating and formulating laws and regulations to protect lakes, strengthening publicity and the education of people, increasing public awareness through participation in systems and mechanic innovations, establishing lake region management institutions, and ensuring implementation of governance and management measures.

关键词： excessive participation prevalence lakeside Research

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基于修正模拟退火算法及溢出面积模型的固定边界布图规划 Article

De-xuan ZOU,Gai-ge WANG,Gai PAN,Hong-wei QI

《信息与电子工程前沿（英文）》 2016年第17卷第11期页码 1228-1244 doi: 10.1631/FITEE.1500386

摘要：无边界布图规划研究面积及线长减少问题很难满足现代设计需求，因此通常被认为是无意义的。我们关注一种难度更大且更有意义的问题--固定边界布图规划。该问题将固定边界约束条件加入无边界布图规划中，使其在实体设计中更有趣、更具挑战性。本文的工作主要分为两部分。第一，提出了一种修正模拟退火算法（Modified simulated annealing algorithm, MSA）。在进化过程初期，用一种新的衰减方程来缓慢减小温度，以增强MSA的全局搜索能力。然后，用传统衰减方程来快速减小温度，以维持MSA的局部搜索能力。第二，设计了一种溢出面积模型来引导MSA寻找可行解，为精炼可行解节省了大量时间。另外，B*-tree是一种有效的布图规划表示法，它被用来执行MSA的扰动操作。最后，以六组带有不同空置率及高宽比的benchmark为例，证实本文所提方法在解决固定边界布图规划问题上的效率，这些问题包括电路n10，n30，n50，n100，n200和n300。与几种现有方法相比，本方法能够更有效地获得令人满意的目标函数值，它们与芯片面积、线长和固定边界约束有关。

关键词：固定边界布图规划；修正的模拟退火算法；全局搜索；溢出面积模型；B*-tree表示法

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Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

《化学科学与工程前沿（英文）》 2007年第1卷第2期页码 167-171 doi: 10.1007/s11705-007-0031-7

摘要： The effects of MgO promoter on the physico-chemical properties and catalytic performance of Ni/AlO catalysts for the partial oxidation of methane to syngas were studied by means of BET, XRD, H-TPR, TEM and performance evaluation. It was found that the MgO promoter benefited from the uniformity of nickel species in the catalysts, inhibited the formation of NiAlO spinel and improved the interaction between nickel species and support. These results were related to the formation of NiO MgO solid solution and MgAlO spinel. Moreover, for the catalysts with a proper amount of MgO promoter, the nickel dispersiveness was enhanced, therefore making their catalytic performance in methane partial oxidation improved. However, the excessive MgO promoter exerted a negative effect on the catalytic performance. Meanwhile, the basicity of MgO promoted the reversed water gas shift reaction, which led to an increase in CO selectivity and a decrease in H2 selectivity. The suitable content of MgO promoter in Ni/AlO catalyst was ?7 wt-%.

关键词： excessive selectivity decrease dispersiveness physico-chemical

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钢产量增长机制的解析及2000—2007年我国钢产量增长过快原因的探索

陆钟武,岳强

《中国工程科学》 2010年第12卷第6期页码 4-11

摘要：

分两步解析钢产量的增长机制，首先在若干假设条件下提出了钢产量增长的基准模式，其主要特点是钢产量与GDP同步增长，分析了基准模式下的钢产量、在役钢量、GDP以及它们的年增长率；然后讨论偏离基准模式的各种可能性，及其对钢产量增速的影响。在此基础上得到了钢产量年增长率的基本计算式。分析了偏离基准模式对单位GDP钢产量的影响。在对钢产量增长机制进行解析的基础上，广泛联系全社会发生的各种现象，提出使我国钢产量增速远远超过GDP增速的16种现象，提出在宏观调控工作中，要区别对待这些现象。从中、日、美三国单位GDP钢产量数据对比可见，我国降低单位GDP钢产量的空间很大。文章为我国钢铁行业的宏观调控提供了新思路。

关键词：钢产量在役钢量 GDP 年增长率机制基准模式