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Numerical analysis of pipeline in J-lay problem

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第11期11卷 908-920页

作者： li-zhong WANG feng yuan Zhen GUO ling-ling li College of Civil Engineering andArchitecture Zhejiang University Hangzhou 310058 China

The pipe configuration and internal loads along the pipeline during the pipeline laying process have long been the focus of engineers. Most researchers simplify the seabed to be rigid and the water to be calm, ignoring the pipe embedment into the seabed and the influence of ocean currents. In this paper, a novel numerical approach is proposed for the laying of pipelines in the so-called J-lay method, taking into account the importance of both pipe embedment and ocean currents. The pipeline is divided into two parts, one part suspended in water, and the other laid on the seabed. The continuity of the two parts at the touch down point (TDP) is guaranteed to make a whole. The feasibility of the model is proved by the comparison between the present model and an analytical model, which shows good agreement in both pipeline configuration and bending moment distribution. Finally, parametric study was performed to consider the influence of current velocity, water depth, top inclination angle, and seabed stiffness, and conclusions are drawn.

关键词： Pipeline J-lay method Numerical model Seabed stiffness Current velocity

An efficient synthesis of 3-(guaiazulene-1-yl)succinimides by addition of guaiazulene to maleimides

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Chinese Chemical Letters 2011年第7期22卷 789-792页

作者： Dao lin Wang Shao Fei li Wei li yuan feng li li Nan lin Key Laboratory of Synthesis & Application of Functional Compound College of Chemistry & Chemical Engineering Bohai University Jinzhou 121001 China

A facile, efficient synthesis of 3-（guaiazulen-l-yl）succinimides was developed by Michael-type addition of guaiazulene to maleimides in the presence of p-toluenesulfonic acid under mild reaction conditions.

关键词： Guaiazulene Succinimidcs Michael-type addition p-Toluenesulfonic acid

Utilization of an H-reversal trajectory of a solar sail for asteroid deflection

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Research in Astronomy and Astrophysics 2011年第10期11卷 1123-1133页

作者： Sheng-Ping Gong Jun-feng li Xiang-yuan Zeng School of Aerospace Tsinghua University Beijing 100084 China

Near Earth Asteroids have a possibility of impacting the Earth and always represent a threat. This paper proposes a way of changing the orbit of the asteroid to avoid an impact. A solar sail evolving in an H-reversal trajectory is utilized for asteroid deflection. Firstly, the dynamics of the solar sail and the characteristics of the H-reversal trajectory are analyzed. Then, the attitude of the solar sail is optimized to guide the sail to impact the target asteroid along an H-reversal trajectory. The impact velocity depends on two important parameters： the minimum solar distance along the trajectory and lightness number of the solar sail. A larger lightness number and a smaller solar distance lead to a higher impact velocity. Finally, the deflection capability of a solar sail impacting the asteroid along the H-reversal trajectory is discussed. The results show that a 10kg solar sail with a lead-time of one year can move Apophis out of a 600-m keyhole area in 2029 to eliminate the possibility of its resonant return in 2036.

关键词： asteroid -- techniques: miscellaneous -- solar sail

Isolation of Human Antibodies Against Hepatitis E Virus From Phage Display library by Immobilized Metal Affinity Chromatography

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Biomedical and Environmental Sciences 2007年第6期20卷 488-494页

作者： YING-WEI CHEN WEN-XIN LUO MING-QIAO WANG JIN WANG li-feng li QUAN yuan JUN ZHANG NING-SHAO XIA National Institute of Diagnostic and Vaccine Development for infectious diseases The Key Laboratory of Ministry of Education for Cell Biology and Tumor Cell Engineering School of Life Sciences Xiamen University Xiamen 361005 Fujian China

Objective To isolate human antibodies against hepatitis E virus from phage display library by a new method of panning phage antibody library based on immobilized metal affinity chromatography （1MAC）. Methods Phage antibody library was allowed to mix with hex-His tagged expressed HEV specific antigen, NE2, in solution for adequate binding before affinity resin for hex-His was added. The non-specific phage antibodies were removed by extensive washing and the specific bound phage antibodies could then be eluted to infect TG1 or repeat the binding process for subsequent rounds of purification. The specificity of the selected human antibodies were tested by antigen competitive EliSA, human sera blocking EliSA, scFv expression, and sequence analysis. Results His-NE2 specific recombinant phages were successfully enriched after panning procedure. Two individual phage clones, 126 and 138, showed 50% inhibition in NE2 antigen competition EliSA and obvious blocking effect by HEV positive serum in blocking EliSA. Soluble scFv of 126, 138 bound to NE2 specifically. Conclusion Two specific human phage antibodies against hepatitis E virus （HEV） from phage display library were isolated by immobilized metal affinity chromatography. The immobilized metal affinity chromatography applied to phage antibody selection was a helpful supplement to the selection in solution.

关键词： HEV antibodies Phage antibody library Affinity chromatography Panning

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舵机减速器转角测量误差分析与补偿

应用基础与工程科学学报 2017年第1期25卷 199-209页

作者：李凯袁峰哈尔滨工业大学电气工程及自动化学院黑龙江哈尔滨150001

在舵机系统的力能传递测试实验中,减速器转角的测量精度是反映舵机特性的重要指标.由于机械安装、零件加工、控制算法采样量化误差和传感器非线性等因素综合影响,角度实测值与理论值之间存在误差并影响测量精度.本文以带有光栅传感器的... 详细信息

在舵机系统的力能传递测试实验中,减速器转角的测量精度是反映舵机特性的重要指标.由于机械安装、零件加工、控制算法采样量化误差和传感器非线性等因素综合影响,角度实测值与理论值之间存在误差并影响测量精度.本文以带有光栅传感器的舵机减速器作为研究对象,通过物理分析、数值计算与系统建模等手段分析了机械、传感器和控制算法采样量化等原因引入的测角误差,提出将机械偏心和传感器非线性作为系统误差,采用最小二乘法构建角度误差指标函数,通过优化指标函数获得由于控制算法采样量化造成角度误差的补偿量的观点.仿真曲线给出了动态静态加载时的误差曲线,以某型舵机减速器为测试设备的实验依此方法进行数据处理,实验结果将测角精度提高了一个数量级(30″),证明了此方法的有效性.

关键词：电动舵机减速器转角测量误差补偿

Application of robust estimation to pit deformation monitoring

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中国有色金属学会会刊：英文版 2005年第S1期15卷 62-64页

作者： li Ming-feng, yuan Bo (Nanjing University of Technology, Nanjing 210009, China)

To guarantee the safety and the quality of the deep pit construction of a high building, it is necessary to monitor the deformation of the supporting structure of the pit. At present, there are mainly two methods to monitor the geometric deformation of the supporting structure of the pit. One is to monitor the displacements of the tops of the piles; the other is to monitor the deep displacements of the piles. Based on the analysis of the characteristics of both the top monitoring data and the deep monitoring data, a united data processing method was put forward. A model of conicoid fitting model was chosen to describe the deformation surface of the pit, and then the robust estimation was adopted to avoid the influence of the gross errors existing in the observations. It was proved effective and accurate to analyze the deformation of the monitoring surface with this method. The steps of the method were concluded in detail.

关键词： pit displacement monitoring conicoid fitting model gross error robust estimation.

Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第1期68卷 329-336页

作者： Yuzhu li Yumeng Gao feng Tian Yu Wang yuan Yao Shaoliang lin Xiang Ma Binbin Xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular Engineering East China University of Science & Technology

Developing organic room-temperature phosphorescence （RTP） materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis（4-alkoxyphenyl）ethane-1,2-dione-alt-（ethylene glycol）x)(P（Bz-alt-EGx）) that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly （COA） process,P（Bz-alt-EGx） self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly （TA） of P（Bz-alt-EGx） obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution （between blue and yellow-green,over125 nm） is realized using the P（Bz-alt-EGx） alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

关键词： self-assembly conformation ordering alternating copolymer phosphorescence emission

Significant reduction of ammonia emissions while increasing crop yields using the 4R nutrient stewardship in an intensive cropping system

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Journal of Integrative Agriculture 2023年第6期22卷 1883-1895页

作者： ZHANG Chong WANG Dan-dan ZHAO Yong-jian XIAO Yu-lin CHEN Huan-xuan liU He-pu feng li-yuan YU Chang-hao JU Xiao-tang College of Tropical Crops Hainan UniversityHaikou 570228P.R.China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193P.R.China

Ammonia (NH_3) emissions should be mitigated to improve environmental *** are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target ***,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize *** the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N *** using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),*** manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N *** return exerted a minor effect on NH_3 *** results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.

关键词： ammonia emission crop yield 4R nutrient stewardship partial manure substitution winter wheat–summer maize cropping system

Differentiating QoS and Un-conflicting Channel-times lot Allocation Algorithm in WDM

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Semiconductor Photonics and Technology 2005年第3期11卷 150-153,160页

作者： li li-xiu feng Jin-yuan YANG Qi-hong College of Phys. and Eng. South China University of TechnologyGuangzhou 510640 CHN

A new effective and reliabl e channel-timeslot allocation algorithm has been proposed, which is applied in WD M optical networks using fiber as their media to allocate the operational reques t. This new algorithm can differentiate the priority of all requests and avoid c onflict and collision in the process of distributing channel and timeslot for th e data waiting for transmission. The method in calculating the best wavelength c hannel and the best timeslot number is simply given. The algorithm is carried o ut in a math language. On the basis of the experiment results, the performance a nd feasibility of the algorithm are analyzed, which prove that the allocation me thod can reach the requirements of an algorithm both in space complexity and tim e complexity .

关键词： WDM Channel Timeslot Conflictr Collision Quality of service