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Efficient and selective extraction of uranium from seawater based on a novel pulsed liquid chromatography radionuclide separation method

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Nuclear Science and Techniques 2023年第2期34卷 13-27页

作者： Jian‑hua ye Tao Yu State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

The novel pulsed liquid chromatography radionuclide separation method presented here provides a new and promising strategy for the extraction of uranium from *** this study,a new chromatographic separation method was proposed,and a pulsed nuclide automated separation device was developed,alongside a new chromatographic *** length of this chromatographic column was 10 m,with an internal warp of 3 mm and a packing size of 1 mm,while the total separation units of the column reached 12,*** most favorable conditions for the separation of nuclides were then obtained through optimizing the separation conditions of the device:Sample pH in the column=2,sample injection flow rate=5.698 mL/min,chromatographic column heating temperature=60℃.Separation experiments were also carried out for uranium,europium,and sodium ions in mixed solutions;uranium and sodium ions in water samples from the Ganjiang River;and uranium,sodium,and magnesium ions from seawater *** separation factors between the different nuclei were then calculated based on the experimental data,and a formula for the separation level was *** experimental results showed that the separation factor in the mixed solution of uranium and europium(1:1)was 1.088,while achieving the initial separation of uranium and europium theoretically required a 47-stage *** the separation factor of 1.50for the uranium and sodium ions in water samples from the Ganjiang River,achieving the initial separation of uranium and sodium ions would have theoretically required at least a 21-stage ***,for the seawater sample separation experiments,the separation factor of uranium and sodium ions was 1.2885;therefore,more than 28 stages of sample separation would be required to achieve uranium extraction from *** novel pulsed liquid chromatography method proposed in this study was innovative in terms of uranium separation and enrichment,while expanding the possibilities

关键词： Pulsed liquid chromatography Nuclide separation Seawater uranium extraction Uranium enrichment

An unscented particle filter for ground maneuvering target tracking

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1588-1595页

作者： GUO rong-hua QIN Zheng Department of Computer Science and Technology Tsinghua University Beijing 100084 China

In this study, an unscented particle filtering method based on an interacting multiple model (IMM) frame for a Markovian switching system is presented. The method integrates the multiple model (MM) filter with an unscented particle filter (UPF) by an interaction step at the beginning. The framework (interaction/mixing, filtering, and combination) is similar to that in a standard IMM filter, but an UPF is adopted in each model. Therefore, the filtering performance and degeneracy phenomenon of particles are improved. The filtering method addresses nonlinear and/or non-Gaussian tracking problems. Simulation results show that the method has better tracking performance compared with the standard IMM-type filter and IMM particle filter.

关键词： Interacting multiple model (IMM) Unscented particle filter (UPF) Ground target tracking Particle filter (PF)

Adaptive fault-tolerant control based on boundary estimation for space robot under joint actuator faults and uncertain parameters

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Defence Technology（防务技术） 2019年第6期15卷 964-971页

作者： rong-hua Lei Li Chen School of Mechanical Engineering and Automation Fuzhou University

Since the joint actuator of the space robot executes the control instructions frequently in the harsh space environment,it is prone to the partial loss of control effectiveness(PLCE)*** adaptive fault-tolerant control algorithm is designed for a space robot system with the uncertain parameters and the PLCE actuator *** mathematical model of the system is established based on the Lagrange method,and the PLCE actuator fault is described as an effectiveness *** lower bound of the effectiveness factors and the upper bound of the uncertain parameters are estimated by an adaptive strategy,and the estimated value is fed back to the control *** with the traditional fault-tolerant algorithms,the proposed algorithm does not need to predetermine the lower bound of the effectiveness factor,hence it is more in line with the actual engineering *** is proved that the algorithm can guarantee the stability of the closed-loop system based on the Lyapunov function *** numerical simulation results show that the proposed algorithm can not only compensate for the uncertain parameters,but also can tolerate the PLCE actuator faults effectively,which verifies the effectiveness and superiority of the control scheme.

关键词： Space robot Actuator faults Uncertain parameters Effectiveness factor Fault-tolerant control

A New Synthetic Method for N-Substituted Selenoamides

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Chinese Chemical Letters 2002年第5期13卷 402-404页

作者： hua rong ZHAO Department of Chemistry Zhejiang UniversityHangzhou 310027

Benzotriazole, aldehydes and primary selenoamides react together with elimination of water to form 1:1:1 adducts which are reduced smoothly by NaBH4 to give the N-substituted selenoamides in good yield.

关键词： Selenoamides benzotriazole aldehydes synthesis.

High temperature oxidation behavior of Ni-based superalloy GH586 in air

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Rare Metals 2017年第11期36卷 878-885页

作者： Jiang-Dong Cao Jun-Song Zhang Yin-Qun hua Zhen rong Rui-Fang Chen Yun-Xia ye School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013 China Mechanical and Electrical Department Nantong Shipping College Nantong 226010 China School of Mechanical Engineering Jiangsu UniversityZhenj iang 212013 China

In this paper, the isothermal oxidation kinetics and oxidation behavior of GH586 superalloy from 800 to 1000℃ were investigated. The oxide scale morphologies of the surfaces and the cross sections after oxidation were characterized by means of X-ray diffraction （XRD） and scanning electron microscope （SEM） equipped with energy-dispersive spectroscopy （EDS）. The results show that the growth of the oxide scales on the surface of superalloy GH586 obeys a parabolic law with the activa- tion energy of 241.4 ***1-1 from 800 to 1000℃ The dense oxide scale formed at 800℃ is mainly composed of Cr203, NiCr204 and a small amount of TiO2. At 900℃, the oxide scale is divided into two layers： the outer layer with multiple cracks is mainly composed of ＂Cr203 and TiO2, while the inner is a layer of dense Cr203. Under the oxide scale, aluminum-rich oxides along the grain bound- aries are generated by the internal oxidation. At 1000 ℃for 100 h, cracks throughout the whole oxide film accel- erate the oxidation rate of Ni-based superalloy GH586 and large blocks of TiO2 in the oxide scale are generated, resulting in the spallation of oxide scale.

关键词： Ni-based superalloy Internal oxidation Hightemperature oxidation behavior Oxidation kinetics

Structure and Evolution of Decadal Spiciness Variability in the North Pacific during 2004-20,Revealed from Argo Observations

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Advances in Atmospheric Sciences 2022年第6期39卷 953-966页

作者： Guanghui ZHOU rong-hua ZHANG CAS Key Laboratory of Ocean Circulation and Waves Institute of Oceanologyand Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100029China Laboratory for Ocean and Climate Dynamics Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China

Ocean spiciness is referred to as density-compensated temperature and salinity variations with warm(cool)and salty(fresh)waters having high(low)spiciness,*** structure and evolution of density-compensated(warm/salty or cool/fresh)spiciness anomalies are investigated in the North Pacific thermocline using Argo observations during the period *** well-organized decadal spiciness events are identified through isopycnal surface *** warm/salty spiciness anomaly of about 0.15°C and 0.05 g kg^(−1)temperature and salinity perturbations on the 25 kg m^(−1)isopycnal surface appeared in the eastern subtropical North Pacific at(18°-30°N,120°-150°W)in 2007,which then migrated southwestward along the mean circulation and arrived in the western tropics at(~15°N,145°E-175°W)in 2012-13,with the reduced salinity perturbation of about 0.043 g kg^(−1).Another cool/fresh spiciness anomaly of about−0.2°C and−0.07 g kg^(−1)temperature and salinity perturbations originated from the eastern subtropics at(120°-150°W,~30°N)in 2014 and followed a similar advective pathway during the period from 2014-15 to *** subduction pathway can be adequately determined by the mean Montgomery stream function on the isopycnal surface;the propagation direction and speed are in good agreement with the expectation for the role played by advection due to the mean geostrophic ***,the subducted decadal spiciness anomalies can have negative feedback on sea surface temperature(SST)variability in the western tropical Pacific through the diapycnal *** identifications of these density-compensated spiciness anomalies and their propagation pathways provide a clear illustration of the oceanic extratropics-tropics interactions in the North Pacific Ocean.

关键词： isopycnal analysis spiciness anomalies subduction pathway advection role decadal variability North Pacific

U-Net Models for Representing Wind Stress Anomalies over the Tropical Pacific and Their Integrations with an Intermediate Coupled Model for ENSO Studies

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Advances in Atmospheric Sciences 2024年第7期41卷 1403-1416页

作者： Shuangying Du rong-hua Zhang Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao266071China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing210044China Laosan Laboratory Qingdao266237China University of Chinese Academy of Sciences Beijing100049China

El Niño-Southern Oscillation(ENSO)is the strongest interannual climate mode influencing the coupled ocean-atmosphere system in the tropical Pacific,and numerous dynamical and statistical models have been developed to simulate and predict *** some simplified coupled ocean-atmosphere models,the relationship between sea surface temperature(SST)anomalies and wind stress(τ)anomalies can be constructed by statistical methods,such as singular value decomposition(SVD).In recent years,the applications of artificial intelligence(AI)to climate modeling have shown promising prospects,and the integrations of AI-based models with dynamical models are active areas of *** study constructs U-Net models for representing the relationship between SSTAs andτanomalies in the tropical Pacific;the UNet-derivedτmodel,denoted asτUNet,is then used to replace the original SVD-basedτmodel of an intermediate coupled model(ICM),forming a newly AI-integrated ICM,referred to as *** simulation results obtained from ICM-UNet demonstrate their ability to represent the spatiotemporal variability of oceanic and atmospheric anomaly fields in the equatorial *** the ocean-only case study,theτUNet-derived wind stress anomaly fields are used to force the ocean component of the ICM,the results of which also indicate reasonable simulations of typical ENSO *** results demonstrate the feasibility of integrating an AI-derived model with a physics-based dynamical model for ENSO modeling ***,the successful integration of the dynamical ocean models with the AI-based atmospheric wind model provides a novel approach to ocean-atmosphere interaction modeling studies.

关键词： U-Net models wind stress anomalies ICM integration of AI and physical components

A Hybrid Neural Network Model for ENSO Prediction in Combination with Principal Oscillation Pattern Analyses

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Advances in Atmospheric Sciences 2022年第6期39卷 889-902页

作者： Lu ZHOU rong-hua ZHANG CAS Key Laboratory of Ocean Circulation and Waves Institute of Oceanologyand Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100029China Laboratory for Ocean and Climate Dynamics Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China

El Niño-Southern Oscillation(ENSO)can be currently predicted reasonably well six months and longer,but large biases and uncertainties remain in its real-time *** approaches have been taken to improve understanding of ENSO processes,and different models for ENSO predictions have been developed,including linear statistical models based on principal oscillation pattern(POP)analyses,convolutional neural networks(CNNs),and so ***,we develop a novel hybrid model,named as POP-Net,by combining the POP analysis procedure with CNN-long short-term memory(LSTM)algorithm to predict the Niño-3.4 sea surface temperature(SST)*** predictions are compared with each other from the corresponding three models:POP model,CNN-LSTM model,and POP-Net,*** POP-based pre-processing acts to enhance ENSO-related signals of interest while filtering unrelated ***,an improved prediction is achieved in the POP-Net relative to *** POP-Net shows a high-correlation skill for 17-month lead time prediction(correlation coefficients exceeding 0.5)during the 1994-2020 validation *** POP-Net also alleviates the spring predictability barrier(SPB).It is concluded that value-added artificial neural networks for improved ENSO predictions are possible by including the process-oriented analyses to enhance signal representations.

关键词： ENSO prediction the principal oscillation pattern(POP)analyses neural network a hybrid approach

锆基金属有机框架捕获黄连中的生物碱类药物活性成分

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分析测试学报 2025年第1期44卷 188-194页

作者：司甜甜赵薇王慧张红玉刘小烨容蓉冯娟娟山东中医药大学药学院山东济南250355 济南大学化学化工学院山东济南250022

采用溶剂热法制备了锆基MOF-808,利用其结构优势实现了中药黄连中生物碱类药物活性成分的富集与捕获,并结合其结构特点探讨了其协同低共熔溶剂捕获生物碱类活性成分过程中的相互作用。通过优化孵育捕获等条件,对黄连粗提液中药根碱的回... 详细信息

采用溶剂热法制备了锆基MOF-808,利用其结构优势实现了中药黄连中生物碱类药物活性成分的富集与捕获,并结合其结构特点探讨了其协同低共熔溶剂捕获生物碱类活性成分过程中的相互作用。通过优化孵育捕获等条件,对黄连粗提液中药根碱的回收率达到85.78%,结合高效液相色谱技术建立了检测黄连粗提液中5种生物碱类活性成分的方法。方法的线性范围为0.1~300μg·L^(-1),检出限为0.02~0.05μg·L^(-1),相对标准偏差为0.40%~4.7%,加标回收率达到69.7%~128%。该研究实现了中药黄连中生物碱类活性成分的高效、快速富集与捕获,为MOFs材料在选择性捕获与富集中药有效成分等领域的研究提供了新思路。

关键词：金属有机框架选择性富集色谱分离生物碱活性成分黄连