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Journal of Environmental Sciences 2019年第1期31卷 318-324页

作者： Fan Bu Baoyu Gao Qinyan Yue Xue Shen Wenyu Wang Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and Engineering Shandong University

Coagulation–ultrafiltration(C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the development of membrane fouling. In this study, we built a dynamic C–UF set-up to carry out the treatment of micro-polluted surface water, to investigate the characteristics of dissolved organic matter from different units. The influences of poly aluminum chloride and poly dimethyldiallylammonium chloride(PDMDAAC) on removal efficiency and membrane fouling were also investigated. Results showed that the dosage of PDMDAAC evidently increased the UV254 and dissolved organic carbon removal efficiencies,and thereby alleviated membrane fouling in the C–UF process. Most hydrophobic bases(HoB)and hydrophobic neutral fractions could be removed by coagulation. Similarly, UF was good at removing HoB compared to hydrophilic substances(HiS) and hydrophobic acid(HoA)fractions. HiS and HoA fractions with low molecule weight accumulated on the surface of the membrane, causing the increase of transmembrane pressure(TMP). Membrane fouling was mainly caused by a removable cake layer, and mechanical cleaning was an efficient way to decrease the TMP.

关键词： Coagulation Ultrafiltration Dissolved organic matter Membrane fouling

Magnetic field intensity dependent microstructure evolution and recrystallization behavior in a Co-B eutectic alloy

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Journal of Materials Science & Technology 2023年第7期138卷 93-107页

作者： Fan Bu Yiyuan Zhang Haoxiang Liu Jun Wang Eric Beaugnon Jinshan Li Yixuan He State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical UniversityXi’an 710072China Collaborative Innovation Center of NPU Shanghai 201108China Institute of Superconducting Materials and Applied Technology Northwestern Polytechnical UniversityXi’an 710072China Univ.Grenoble Alpes INSA ToulouseUniversity Toulouse Paul SabatierEMFLCNRSLNCMIGrenoble 38000France

Systematic understanding on the magnetic field intensity dependent microstructure evolution and re-crystallization behavior in a Co-B eutectic alloy under a constant undercooling(ΔT≈100 K)were carried out.Absent of the magnetic field,the comparable size of divorced FCC-Co and Co_(3)B eutectic ellipsoidal grains coexist with a few regular lamellas.When the magnetic field is less than 15 T,the elongated primary FCC-Co dendrites parallel to the magnetic field with the dispersed FCC-Co nano-particles em-bedded within the Co_(3)B matrix occupy the inter-dendrite regions.Once the magnetic field increases to 20 T,the FCC-Co/Co_(2)B anomalous eutectic colonies dominate.The formation mechanism of Co_(2)B phase is discussed from several aspects of the competitive nucleation,the chemical redistribution induced by the thermomagnetic-induced convection and magnetic dipole interaction,and the strain-induced trans-formation.Furthermore,the application of magnetic field is found to promote recrystallization,proved by the lower density of misorientation,the appearance of FCC-Co annealed twins and more Co_(3)B sub-grains.This work could further enrich our knowledge about the magnetic-dependent microstructure evolution and recrystallization process in the undercooled Co-B system and provide guidance for controlling the microstructures and properties under extreme conditions.

关键词： Magnetic field Undercooled solidification Microstructure evolution Recrystallization Co-B alloy

The Promoting Effect of Multifunctional Groups on the Thermal and Mechanical Properties of PVC Materials

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Journal of Renewable Materials 2023年第2期11卷 867-880页

作者： Mei Wang Xinzhu fan Xianghai Song Quan bu School of Agricultural Engineering Jiangsu UniversityZhenjiang212013China Institute of the Green Chemistry and Chemical Technology School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang212013China

The development of PVC materials grafted with mannich base originated from myrcene(P-MAM-g,where the mannich base derived from myrcene is abbreviated as MAM)via green and effective synthetic methods is a good strategy to avoid unacceptable discoloration and deterioration of thermal and mechanical properties caused by autocatalytic dehydrochlorination(DHC)during PVC processing.In this study,MAM with double bonds,amino groups,ester groups,and phospholipid groups was introduced into the chains of PVC to improve the thermal stability of PVC.The experimental results showed that the covalent attachment of MAM to PVC enhanced both the initial and the long-term stability of PVC.The enhanced performance of P-MAM-g compared with unmodified PVC is attributed to the simultaneous introduction of double bonds and amino groups into the PVC structure.The double bonds trapped the unstable chlorine atoms originated from the degradation of the PVC chain and reacted with the labile macromolecular radicals originated from PVC,thus inhibiting the radical degradation of the PVC chain.Furthermore,the amino groups absorbed the HCl produced in the degradation of PVC,inhibiting the adverse effects of HCl.P-MAM-g displayed better intrinsic flexibility and anti-migration ability of organic functional components compared with the control PVC materials.A possible stabilizing mechanism of the P-MAM-g was also presented.

关键词： Myrcene poly(vinyl chloride) covalent grafting self-stabilization

Grow rice under sunshine of Xizang/Tibet:promise and challenges

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Journal of Genetics and Genomics 2024年第3期51卷 265-267页

作者： Chunkun fan Xiaoming Zheng Qingbo Yuan Tao Wang Qian Qian Qingyun bu fan Chen Agricultural Institute Xizang Academy of Agricultural and Animal Husbandry ScienceLasaXizang 850032China National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of AgriculturalSciencesBeijing 100081China Sanya National Research Institute of Breeding in Hainan Chinese Academy of Agricultural SciencesBeijing 572000China Yazhouwan National Laboratory SanyaHainan 572704China Chengdu Institute of Biology Chinese Academy of SciencesChengduSichuan 610041China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesHarbinHeilongjiang 150081China

Xizang,previously known as Tibet,is located in the southwest region of China and is the highest region of the Qinghai-Tibet Plateau(QzP),with an average altitude of over 4000 m.With the development of modern agriculture,the grain productivity in Xizang has been effectively improved.The total annual grain production has increased from 558,700 tons in 1988 to 1044,000 tons in 2018(Xizang Statistical Year Book).

关键词： sunshine Tibet southwest

国图藏清彩绘本《直隶省津保一带淀河图》绘制时间考

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文献 2024年第2期 117-135,F0002页

作者：卜凡河北大学历史学院

国家图书馆藏清绢底彩绘本《直隶省津保一带淀河图》,在研究历史时期冀中平原地区与海河水系演变方面具有重要的参考价值。此前学界认为该图绘制于清光绪年间。通过对该图所绘永定河、子牙河及淀河等河湖水系与相关水利工程样态进行分... 详细信息

国家图书馆藏清绢底彩绘本《直隶省津保一带淀河图》,在研究历史时期冀中平原地区与海河水系演变方面具有重要的参考价值。此前学界认为该图绘制于清光绪年间。通过对该图所绘永定河、子牙河及淀河等河湖水系与相关水利工程样态进行分析考证,并与国家图书馆藏清光绪年间《天津至保定河图》对比可知,《直隶省津保一带淀河图》的绘制时间应在清乾隆十一年(1746)至乾隆十六年(1751)之间。该图是乾隆前期畿辅水利工程建设成果的直观记录。

关键词：《直隶省津保一带淀河图》乾隆时期冀中平原海河水系

Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 32-42页

作者： Xiao Liu Pingting Lin Fan Bu Shaoling Zhuang Shoudao Huang CES&IEEE the College of Electrical and Information Engineering Hunan UniversityChangsha 410082China CES

The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems.

关键词： Generator optimization Gaussian Process Regression(GPR) Conditional Likelihood Lower Bound Search(CLLBS) Constraint improvement expectation(CEI) Finite element calculation

Low Bit Rate Underwater Video Image Compression and Coding Method Based on Wavelet Decomposition

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China Communications 2020年第9期17卷 210-219页

作者： Yonggang He Xiongzhu bu Ming Jiang Maojun fan Nanjing University of Science&Technology Nanjing 210094China The Third Research Institute of China Electronics Technology Corporation Beijing 100015China

In view of the limited bandwidth of underwater video image transmission,a low bit rate underwater video compression coding method is proposed.Based on the preprocessing process of wavelet transform and coefficient down-sampling,the visual redundancy of underwater image is removed and the computational coefficients and coding bits are reduced.At the same time,combined with multi-level wavelet decomposition,inter frame motion compensation,entropy coding and other methods,according to the characteristics of different types of frame image data,reduce the number of calculations and improve the coding efficiency.The experimental results show that the reconstructed image quality can meet the visual requirements,and the average compression ratio of underwater video can meet the requirements of underwater acoustic channel transmission rate.

关键词： low bit rate down-sampling wavelet decomposition underwater video coding

Circadian rhythms driving a fast-paced root clock implicate species-specific regulation in Medicago truncatula

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Journal of Integrative Plant Biology 2021年第8期63卷 1537-1554页

作者： Liping Wang Anqi Zhou Jing Li Mingkang Yang Fan Bu Liangfa Ge Liang Chen Wei Huang State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources South China Agricultural UniversityGuangzhou510642 China College of Life Sciences South China Agricultural UniversityGuangzhou510642 China Department of Grassland Science College of Forestry and Landscape ArchitectureSouth China Agricultural UniversityGuangzhou510642 China Guangdong Engineering Research Center for Grassland Science Guangzhou510642 China Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm South China Agricultural UniversityGuangzhou510642 China Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms College of Life SciencesSouth China Agricultural UniversityGuangzhou510642 China

Plants have a hierarchical circadian structure comprising multiple tissue-specific oscillators that operate at different speeds and regulate the expression of distinct sets of genes in different organs.However,the identity of the genes differentially regulated by the circadian clock in different organs,such as roots,and how their oscillations create functional specialization remain unclear.Here,we profiled the diurnal and circadian landscapes of the shoots and roots of Medicago truncatula and identified the conserved regulatory sequences contributing to transcriptome oscillations in each organ.We found that the light-dark cycles strongly affect the global transcriptome oscillation in roots,and many clock genes oscillate only in shoots.Moreover,many key genes involved in nitrogen fixation are regulated by circadian rhythms.Surprisingly,the root clock runs faster than the shoot clock,which is contrary to the hierarchical circadian structure showing a slow-paced root clock in both detached and intact Arabidopsis thaliana(L.)Heynh.roots.Our result provides important clues about the species-specific circadian regulatory mechanism,which is often overlooked,and possibly coordinates the timing between shoots and roots independent of the current prevailing model.

关键词： circadian clock hierarchical coupling structure Medicago truncatula nitrogen fixation oscillator networks

文安遥堤之争:明清冀中地方社会治水矛盾考察

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中国农史 2022年第3期41卷 127-137页

作者：卜凡首都师范大学历史学院北京100048

明代万历年间,文安县因水患频仍而修筑文安遥堤,但因加深了不同州县之间治水利益的矛盾,遥堤自修建之始就引发了文安县与雄县等州县之间的一系列冲突。在清代前中期,虽然这种冲突因治水利益的暂时趋同与直隶水系得到系统治理而稍有缓和... 详细信息

明代万历年间,文安县因水患频仍而修筑文安遥堤,但因加深了不同州县之间治水利益的矛盾,遥堤自修建之始就引发了文安县与雄县等州县之间的一系列冲突。在清代前中期,虽然这种冲突因治水利益的暂时趋同与直隶水系得到系统治理而稍有缓和,却在晚清时期由于水系变迁以及政治、经济方面的危机而再次加剧。为了与周边州县达成和解,文安县最后在光绪年间不得不将遥堤完全平毁。作为明清冀中地方社会治水矛盾的一个典型案例,文安遥堤之争反映出当时政治、经济等方面的社会危机,而以晚清时期表现得最为突出。

关键词：文安遥堤冀中地区地方社会治水矛盾

Automatic calibration for wobble errors in shallow water multibeam bathymetries

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Journal of Oceanology and Limnology 2022年第5期40卷 1937-1949页

作者： Tianyu YUN Xianhai bu Zhe XING Zhendong LUAN Miao fan fanlin YANG College of Geodesy and Geomatics Shandong University of Science and TechnologyQingdao 266590China National Marine Data and Information Service Tianjin 300012China Key Laboratory of Marine Geology and Environment&Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Key Laboratory of Ocean Geomatics Ministry of Natural ResourcesQingdao 266590China

The wobble errors caused by the imperfect integration of motion sensors and transducers in multibeam echo-sounder systems(MBES)manifest as high-frequency wobbles in swaths and hinder the accurate expression of high-resolution seabed micro-topography under a dynamic marine environment.There are many types of wobble errors with certain coupling among them.However,those current calibration methods ignore the coupling and are mainly manual adjustments.Therefore,we proposed an automatic calibration method with the coupling.First,given the independence of the transmitter and the receiver,the traditional georeferenced model is modified to improve the accuracy of footprint reduction.Secondly,based on the improved georeferenced model,the calibration model associated with motion scale,time delay,yaw misalignment,lever arm errors,and soundings is constructed.Finally,the genetic algorithm(GA)is used to search dynamically for the optimal estimation of the corresponding error parameters to realize the automatic calibration of wobble errors.The simulated data show that the accuracy of the calibrated data can be controlled within 0.2%of the water depth.The measured data show that after calibration,the maximum standard deviation of the depth is reduced by about 5.9%,and the mean standard deviation of the depth is reduced by about 11.2%.The proposed method has significance in the precise calibration of dynamic errors in shallow water multibeam bathymetrie s.

关键词： multibeam echo-sounder systems footprint reduction wobble errors genetic algorithm automatic calibration