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Journal of Mountain Science 2024年第1期21卷 84-99页

作者： QIN Zipeng TIAN Yan gao siyuan ZHOU Jianfen HE Xiaohui HE Weizhong gao Jingquan School of Water Conservancy and Environment Engineering Zhejiang University of Water Resources and Electric PowerHangzhou 310018China Department of Civil Engineering Imperial College LondonLondonSW71BFEngland Lanxi Water Affairs Bureau Lanxi 321102China Zhejiang Water Conservancy Engineering Consulting Co. LtdHangzhou 310051China

The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.

关键词： Stability analysis Multiple factors Antiseepage reinforcement Upside-down hanging well Grouting curtain Ancient levee

Characterization and application of a recombinant dopa decarboxylase from Harmonia axyridis for the efficient biosynthesis of dopamine

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Chinese Journal of Chemical Engineering 2022年第1期35卷 449-456页

作者： siyuan gao Yuanke Guo Chen Ma Ding Ma Kequan Chen Pingkai Ouyang Xin Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China

Here,a dopa decarboxylase(DDC)from Harmonia axyridis was heterogeneously expressed in Escherichia coli for the efficient biosynthesis of *** the production of recombinant DDC,the cultivation conditions including IPTG concentration,temperature and induction time were optimized and obtained an optimal specific enzyme activity of 51.72 U·mg^(-1) crude *** the purification of DDC with a recovery yield of 68.79%,its activity was further *** Vmax,Km,Kcat,and Kcat/Km of DDC for d ihyd roxy pheny la la nine(dopa)were 0.02 mmol·ml^(-1)·s^(-1),2.328 mmol·ml^(-1),10435.90 s^(-1) and4482.77 ml,mmol *** highest DDC activity was observed at the condition of pH 7.5 and 45℃.With the purified DDC,the feasibility to produce dopamine from L-dopa was *** optimal yield was determined at the following bioconversion conditions:pH of 7,0,the reaction temperature of 40℃,0.4 mmol·L^(-1) of PLP and 4 g·L^(-1) of L-dopa,Subsequently,a fed-batch process for the production of dopamine was developed and the effect of oxygen was *** titer,yield and productivity of dopamine reached up to 21.99 g·L^(-1)80.88%and 14.66 g·L^(-1)·h^(-1) at 90 min under anaerobic condition.

关键词： Dopa decarboxylase Dopamine Enzyme catalysis Fed-batch bioconversion

The production of biobased diamines from renewable carbon sources: Current advances and perspectives

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Chinese Journal of Chemical Engineering 2021年第2期34卷 4-13页

作者： Xin Wang siyuan gao Jing Wang Sheng Xu Hui Li Kequan Chen Pingkai Ouyang State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816JiangsuChina Zhejiang Zhongshan Chemical Industry Group Co.Ltd Huzhou 313100Chin

Bio-based diamines are considered to be a promising alternative to traditional fossil-fuel-based diamines,the important platform chemical for the synthesis of polymer *** this review,the current status of the art of the synthesis of aliphatic and aromatic diamines from renewable biomass are *** the case of aliphatic diamines,we describe strategies for biologically producing diamines with different carbon numbers including 1,3-diaminopropane,1,4-butanediamine,1,5-pentanediamine,1,6-diaminohexane,1,8-diaminooctane,1,10-diaminodecane,and 1,*** addition,aromatic diamines produced from various kinds of renewable biomass,including lignin,cashew nut shell,and terpenoids,are reviewed ***,the application of typical diamines in synthesis of polyurethane and polyamide are also reviewed.

关键词： Aliphatic diamines Aromatic diamines Polyamide Polyurethane

The shortest period of coal spontaneous combustion on the basis of oxidative heat release intensity

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International Journal of Mining Science and Technology 2014年第1期24卷 99-103页

作者： Yang Yongliang Li Zenghua Hou Shisong Gu Fanjun gao siyuan Tang Yibo School of Safety Engineering China University of Mining & Technology Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education Southeast University State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology

It’s necessary to forecast the shortest spontaneous combustion period for preventing and controlling the coal spontaneous *** the experimental process,a calculating model of the SSCP is established on the basis of the oxidative heat release intensity and thermal capacity at different *** to the basic parameters of spontaneous combustion,heat of water evaporation and gas desorption,the SSCPs of different coals are further ***,this study analyzed the relationships of the SSCP and the judging indexes of the self-ignite *** result shows that the SSCP non-linearly increases with the decrease of dynamic oxygen adsorption and increase of activation *** with the practical fire situation of mine,this reliable method can meet the actual requirement of mine production.

关键词： Coal spontaneous combustion The shortest period of spontaneouscom bustion Heat release intensity of coal oxidation Thermal capacity Judging indexes

Advance of tolerance engineering on microbes for industrial production

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Synthetic and Systems Biotechnology 2023年第4期8卷 697-707页

作者： siyuan gao Yang Liao Hao He Huiling Yang Xuewei Yang Sheng Xu Xin Wang Kequan Chen Pingkai Ouyang State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing211816JiangsuChina Petrochemical Research Institute of PetroChina Co.Ltd. Beijing102206China

Industrial microbes have become the core of biological manufacturing,which utilized as the cell factory for production of plenty of chemicals,fuels and ***,the challenge that the extreme stress conditions exist in production is unavoidable for cell ***,to enhance robustness of the chassis cell lays the foundation for development of ***,the researches on cell tolerance covered various aspects,involving reshaping regulatory network,cell membrane modification and other stress *** fact,the strategies employed to improve cell robustness could be summarized into two directions,irrational engineering and rational *** this review,the metabolic engineering technologies on enhancement of microbe tolerance to industrial conditions are ***,the novel thoughts emerged with the development of biological instruments and synthetic biology are discussed.

关键词： Tolerance engineering Stress condition Industrial microbe Metabolism engineering Synthetic biology

制造/再制造企业RFID技术采纳的投资决策分析

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计算机集成制造系统 2019年第8期25卷 2079-2086页

作者：李文川章鑫高思源南昌航空大学经济管理学院

为了将无线射频识别(RFID)技术更好地应用于物联网智能感知,以促进制造业智能化升级和服务化转型,针对寡头垄断市场环境下,制造/再制造企业是否采纳RFID技术的投资决策问题进行了研究。分析了废旧产品回收环节的误回收问题及其对回收总... 详细信息

为了将无线射频识别(RFID)技术更好地应用于物联网智能感知,以促进制造业智能化升级和服务化转型,针对寡头垄断市场环境下,制造/再制造企业是否采纳RFID技术的投资决策问题进行了研究。分析了废旧产品回收环节的误回收问题及其对回收总量的影响,构建了企业在不采纳RFID技术的情况下考虑误回收概率的两阶段收益模型。考虑到采纳RFID技术可消除误回收率,构建了企业RFID技术采纳投资的两阶段收益模型。通过数理推导,得到企业采纳RFID技术前后两类收益模型的最优产品定价策略和最优利润函数。在此基础上,通过两类模型最优收益决策的临界条件,将可回收率划分为3个区间,探讨了不同区间上制造商愿意投资RFID技术的单位标签成本阈值。最后,通过数值算例验证了理论推导结果。

关键词： RFID 制造/再制造企业投资决策误回收率成本阈值

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大庆油田二类油层交联聚合物微球调剖剂性能

大庆石油地质与开发 2013年第4期32卷 112-116页

作者：高思远大庆油田有限责任公司勘探开发研究院黑龙江大庆163712

为研究交联聚合物微球在大庆油田二类油层的适应性，利用扫描电镜和微孔滤膜实验研究了交联聚合物微球的颗粒微观形态和封堵性能，通过岩心流动和驱油实验评价了交联聚合物在天然岩心中的流动性能及驱油效果。结果表明：交联聚合物微球... 详细信息

为研究交联聚合物微球在大庆油田二类油层的适应性，利用扫描电镜和微孔滤膜实验研究了交联聚合物微球的颗粒微观形态和封堵性能，通过岩心流动和驱油实验评价了交联聚合物在天然岩心中的流动性能及驱油效果。结果表明：交联聚合物微球在水溶液中可形成较为规整的球形颗粒，且多数微球粒子尺寸小于1．0μm；交联聚合物微球的封堵性能明显好于“中分”聚合物溶液，交联聚合物微球水化2～3d，其封堵性能最佳；无机盐使交联聚合物微球的封堵性能降低；交联聚合物微球可以进入孔道内部并封堵，能有效提高注入水的波及体积，降低非均质性，提高原油采收率。

关键词：交联聚合物微球微孔滤膜扫描电镜天然岩心二类油层大庆油田

基于随机Petri网的企业RFID技术采纳内化建模与仿真

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计算机集成制造系统 2020年第2期26卷 470-480页

作者：李文川高思源章鑫冯良清南昌航空大学经济管理学院

作为智能制造的重要使能技术之一,RFID技术采纳及内化对推动传统企业创新升级和服务化转型具有重要意义。为了深入揭示企业RFID技术采纳内化过程的规律,在采纳内化概念模型的基础之上,构建了Petri网模型。通过Petri网模型可达集同构了Ma... 详细信息

作为智能制造的重要使能技术之一,RFID技术采纳及内化对推动传统企业创新升级和服务化转型具有重要意义。为了深入揭示企业RFID技术采纳内化过程的规律,在采纳内化概念模型的基础之上,构建了Petri网模型。通过Petri网模型可达集同构了Markov链模型,得到了变迁的实施速率矩阵,并通过求解该矩阵,进一步得到了超定线性方式组。以“沃尔玛集团RFID技术创新”为例,对其RFID技术采纳内化过程进行了仿真模拟。研究结果表明:技术、政策等外部环境的整体优化会有效推动企业RFID采纳,并提升其内化价值;政府、企业、产品/方案供应商对RFID技术采纳给予足够的推动,会使RFID采纳内化过程创造更大价值;RFID实施之前的准备工作(试运行、结果反馈等)有助于积累整个RFID采纳内化系统的正向效益。可为促进企业RFID采纳内化的科学化、合理化提供理论支持和实践经验。

关键词： RFID技术采纳内化建模与仿真随机Petri网 Markov链

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全捷联激光制导寻的器测角精度分析与优化

红外与激光工程 2015年第7期44卷 2169-2174页

作者：高思远刘慧朱明超张鑫白杨中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049

为了降低激光制导武器系统成本并保证打击精度,设计了全捷联激光制导寻的器,并对影响打击精度的关键技术指标测角精度进行了研究。首先对影响测角精度的主要因素增益控制进行了分析,通过对四通道可变增益放大器进行增益标定和最小二乘... 详细信息

为了降低激光制导武器系统成本并保证打击精度,设计了全捷联激光制导寻的器,并对影响打击精度的关键技术指标测角精度进行了研究。首先对影响测角精度的主要因素增益控制进行了分析,通过对四通道可变增益放大器进行增益标定和最小二乘拟合得到增益控制曲线,接着讨论了离散量控制下增益补偿的方法及误差,仿真计算得到不同配置模式下增益补偿前和补偿后的光斑重心计算误差。对全捷联激光制导寻的器进行激光照射测角试验,结果表明,增益补偿后能够消除系统误差约5.6 mrad,在中心线性视场范围内,测角精度达到2 mrad。该系统满足某机载轻型空地导弹对激光制导寻的器测角精度的要求,为精确末制导提供保障。

关键词：激光制导四象限探测器可变增益放大器测角精度

空间激光通信中变步长CMA-LMS均衡算法

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光通信技术 2020年第7期44卷 36-39页

作者：佟欣刘智高思远长春理工大学电子与信息工程学院长春130022 长春理工大学空间光电技术研究所长春130022

针对空间激光通信中无线光信号传输过程的串扰以及噪声问题,提出一种结合恒模算法(CMA)和最小均方(LMS)算法的两级级联变步长自适应均衡算法——CMA-LMS均衡算法,使步长因子的大小在一定范围与理论呈非线性关系。利用理论数据和步长因... 详细信息

针对空间激光通信中无线光信号传输过程的串扰以及噪声问题,提出一种结合恒模算法(CMA)和最小均方(LMS)算法的两级级联变步长自适应均衡算法——CMA-LMS均衡算法,使步长因子的大小在一定范围与理论呈非线性关系。利用理论数据和步长因子的乘积对算法变量进行更新,实现信道的非线性自适应均衡。实验结果表明:CMA-LMS均衡算法能够提高系统的性能;在16阶正交幅度调制(16QAM)下,CMA-LMS均衡算法能够有效抑制系统的噪声和串扰问题。

关键词：自适应滤波空间激光通信均衡步长因子恒模算法