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Real-data assimilation experiment with a joint data assimilation system: assimilating carbon dioxide mole fraction measurements from the Greenhouse gases Observing Satellite

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Atmospheric and Oceanic Science Letters 2016年第2期9卷 107-113页

作者： HAN Rui TIAN Xiang-jun fu yu CAI Zhao-Nan Institute of Atmospheric Sciences Chengdu University of Information Technology/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province International Center for Climate and Environment Sciences Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences Key Laboratory of Middle Atmosphere and Global Environment Observation Chinese Academy of Sciences

The performance of a joint data assimilation system（Tan-Tracker）,which is based on the PODEn4 Dvar assimilation method,in assimilating Greenhouse gases Observing SATellite（GOSAT） carbon dioxide（CO2） data,was *** 3D CO2 concentrations and CO2 surface fluxes（CFs） from2010 were simulated using a global chemistry transport model（GEOS-Chem）.TheTan-Tracker system used the simulated CO2 concentrations and fluxes as a background field and assimilated the GOSAT column average dry-air mole fraction of CO2（X（CO2）） data to optimize CO2 concentrations and CFs in the same assimilation *** simulated X（CO2）（X（CO2）Sim）） and assimilated X（CO2）（X（CO2）,TT） data retrieved at different satellite scan positions were compared with GOSAT-observed X（CO2）（X（CO2）,obs）*** average RMSE between the monthly X（CO2）,TT and X（CO2）,Obs data was significantly（30%） lower than the average RMSE between X（CO2）,Sim and X（CO2）,Obs）.Specifically,reductions in error were found for the positions of northern Africa（the Sahara）,the Indian peninsula,southern Africa,southern North America,and western *** difference between the correlation coefficients of the X（CO2）,Sim）and X（CO2）,Obs and those of the X（CO2）Π）,TT and X（CO2）,Obs was only *** general,the Tan-Tracker system performed very well after assimilating the GOSAT data.

关键词： Tan-Tracker GEOS-Chem GOSAT PODEn4DVar atmospheric CO2 concentration

NUMERICAL INVESTIGATION OF PERFORMANCE OF AN AXIAL-FLOW PUMP WITH INDUCER

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Journal of Hydrodynamics 2007年第6期19卷 705-711页

作者： LI Yao-jun WANG fu-jun College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 China

The interaction of flow through the inducer and impeller of an axial-flow pump equipped with an inducer has significant effect on its performance. This article presents a recent numerical investigation on this topic. The studied pump has an inducer with 3 blades mounted on a conical hub and a 6-blade impeller. The blade angle of the impeller is adjustable to generate different relative circumferential angles between the inducer blade trailing edge and the impeller blade leading edge. A computational fluid dynamics code was used to investigate the flow characteristics and performance of the axial-flow pump. For turbulence closure, the RNG k-ε model was applied with an unstructured grid system. The rotor-stator interaction was treated with a Multiple Reference Frame （MRF） strategy. Computations were performed in different cases： 7 different relative circumferential angles （ Δθ ） between the inducer blade trailing edge and the impeller blade leading edge, and 3 different axial gaps （G） between the inducer and the impeller. The variation of the hydraulic loss in the rotator was obtained by changing Δθ . The numerical results show that the pressure generated is minimum in the case of （ G = 3%D）, which indicates that the interference between inducer and impeller is strong if the axial gap is small. The pump performances were predicted and compared to the experimental measurements. Recommendations for future modifications and improvements to the pump design were also given.

关键词： axial-flow pump inducer CFD numerical simulation of flow

Inhibition of pancreatic stellate cell activity by adipose-derived stem cells

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Hepatobiliary & Pancreatic Diseases International 2015年第2期14卷 215-221页

作者： fu-Xiang yu Long-Feng Su Chun-Lei Dai Yang Wang Yin-Yan Teng jun-Hui fu Qi-yu Zhang Yin-He Tang Department of Hepatobiliary and Pancreatic Surgery FirstAffiliatedHospital WenzhouMedicalCollege Department of Hepatobiliary and Pancreatic Surgery FirstAffiliatedHospitalWenzhouMedicalCollege

BACKGROUND：Pancreatic stellate cells（PSCs）play a critical role in the development of pancreatic *** this study we used a novel method to isolate and culture rat PSCs and then investigated the inhibitory effects of adipose-derived stem cells（ADSCs）on activation and proliferation of ***：Pancreatic tissue was obtained from SpragueDawley rats for PSCs *** cell cultures were adopted for co-culture of ADSCs and PSCs. PSCs prolifera- tion and apoptosis were determined using CCK-8 and flow cytometry, respectively, a-SMA expressions were analyzed using Western blotting. The levels of cytokines [nerve growth factor （NGF）, interleukin-10 （IL-10） and transforming growth factor-ill （TGF-[31）] in conditioned medium were detected by ELISA. Gene expression （MMP-2, MMP-9 and TIMP-1） was analyzed using qRT-PCR. RESULTS： This method produced 17.6_＋6.5 ~ 103 ceils per gram of the body weight with a purity of 90%-95% and a viability of 92%-97%. Co-culture of PSCs with ADSCs significantly inhib- ited PSCs proliferation and induced PSCs apoptosis. Moreover, a-SMA expression was significantly reduced in PSCs＋ADSCs compared with that in PSC-only cultures, while expression of fibrinolytic proteins （e.g., MMP-2 and MMP-9） was upregulated and anti-fibrinolytic protein （TIMP-1） was downregulated. In addition, NGF expression was up-regulated, but IL-10 and TGF-β1 expressions were down-regulated in the coculture conditioned medium compared with those in the PSC- only culture medium. CONCLUSIONS： This study provided an easy and reliable technique to isolate PSCs. The data demonstrated the inhibitory effects of ADSCs on the activation and proliferation of PSCs in vitro.

关键词： pancreatic stellate cells isolation mesenchymal stem cells pancreatic fibrosis fibrinolytic protein

Detection and Estimation of False Data Injection Attacks for Load Frequency Control Systems

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 861-870页

作者： jun Ye Xiang yu Hangzhou Innovation Institute Beihang UniversityHangzhouChina School of Automation Science and Electrical Engineering Beihang UniversityBeijingChina

False data injection attacks(FDIAs)against the load frequency control(LFC)system can lead to unstable operation of power *** this paper,the problems of detecting and estimating the FDIAs for the LFC system in the presence of external disturbances are ***,the LFC system model with FDIAs against frequency and tie-line power measurements is ***,a design procedure for the unknown input observer(UIO)is presented and the residual signal is generated to detect the *** UIO is designed to decouple the effect of the unknown external disturbance on the residual *** that,an attack estimation method based on a robust adaptive observer(RAO)is proposed to estimate the state and the FDIAs *** order to improve the performance of attack estimation,the H¥technique is employed to minimize the effect of external disturbance on estimation errors,and the uniform boundedness of the state and attack estimation errors is proven using Lyapunov stability ***,a two-area interconnected power system is simulated to demonstrate the effectiveness of the proposed attack detection and estimation algorithms.

关键词： External disturbance false data injection attacks load frequency control robust adaptive observer unknown input observer

Annealing and optical homogeneity of large ZnGeP_(2) single crystal

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Rare Metals 2022年第9期41卷 3214-3219页

作者： Li-Qiang Cao Bei-jun Zhao Shi-fu Zhu Bao-jun Chen Zhi-yu He Deng-Hui Yang Hui Liu Hu Xie College of Materials Science and Engineering Sichuan UniversityChengdu610064China

A high-quality ZnGeP_(2)(ZGP)single crystal with large size ofΦ30 mm×80 mm was grown by a modified vertical Bridgman *** wafers were annealed with ZGP polycrystalline powder for 300 h at 550,600 and 650℃,*** as-grown and annealed crystals were characterized by X-ray diffraction(XRD)analysis,Fourier transform infrared spectroscopy(FTIR),IR microscope and energy-dispersive spectroscopy(EDS).Results show that the quality of all wafers is improved evidently after annealing and the optimum annealing temperature obtained is 600℃.The IR transmittance of the wafer measured by FTIR is up to 56.78%at wavelength of 2.0μm nearby and exceeds 59.00%in the wavelength range of 3.0-8.0μ*** deviations from stoichiometry decrease,and the homogeneity of the crystal is also improved after *** this paper,scanning infrared map was proposed as a new nondestructive method to evaluate optical quality and homogeneity of crystal through comparing the IR transmittance with the three-dimensional IR spectral contour map.

关键词： ZnGeP_(2)crystals Annealing Infrared transmittance Scanning infrared map Optical homogeneity

Comparative Studies on Properties of Polymers with Bulky Side Groups Synthesized by Cyclopolymerization of α,ω-Dienes and α,ω-Diynes

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Chinese Journal of Polymer Science 2019年第2期37卷 149-156页

作者： Shao-Fei Song Xiao-yu Liu Hao Zhang Zhi-Sheng fu jun-Ting Xu Zhi-Qiang Fan Ministry of Education Key Laboratory of Macromolecular Synthesis and functionalization Department of Polymer Science and Engineering Zhejiang University

Four polymers containing five-membered rings in the main chain, with or without conjugation structure along the backbone and with or without conjugated pendent groups, were designed and synthesized by metathesis cyclopolymerization of functionalized α,ω-diynes, and cyclopolymerization of functionalized α,ω-dienes catalyzed by the α-diimine palladium-based catalyst, respectively. High to moderate monomer conversions were achieved. Chain structure, molecular weight, and molecular weight distribution(MWD) of the cyclopolymerization products were characterized by ~1 H-, ^(13) C-NMR, FTIR, and GPC. The polymers showed regular main chain structures,moderately high molecular weight, and narrow MWD. Thermal properties and chain stacking behaviors of the polymers were investigated by differential scanning calorimetry(DSC) and X-ray diffraction(XRD) as well as atomic force microscopy(AFM). The polymer with conjugation system in both the backbone and the pendent groups exhibited UV-Vis absorption at a much longer wavelength than those with the conjugation only in the backbone or only in the side groups. The polymers with conjugated backbone need more space for chain stacking, and the conjugated backbone causes enhanced size of polymer particles assembled from solution. The results showed that primary microstructures of the polymer exerted significant influences on the physical properties.

关键词： Cyclopolymerization α,ω-Diene α,ω-Diyne Conjugation system Properties

Interpulse interference of electron emission from an atom irradiated by sinusoidally phase-modulated pulse

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Chinese Physics B 2018年第10期27卷 283-287页

作者： Hai-Ying yuan fu-Ming Guo Di-yu Zhang jun Wang Ji-Gen Chen yu-jun Yang Institute of Atomic and Molecular Physics Jilin University Changchun 130012 China Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy (Jilin University) Changchun 130012 China Department of Physics and Materials Engineering Taizhou University Taizhou 318000 China

We theoretically investigate the photoelectron emission from an atom irradiated by an amplitude modulated sinusoidally phase-modulated pulse through solving the time-dependent Schr¨odinger equation in the momentum space. By controlling the phase amplitude of the pulse in the frequency domain, it can be found that the photoelectron spectra appear as explicit interference phenomena, which originated from the interference between the directly ionized electron and the ionization of the pre-excited atom from different subpulses.

关键词： high-order harmonic generation above threshold ionization

Preparation of Inoculants Used in Superalloy and Analysis of the Atomic Matching Models

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Journal of Materials Science & Technology 2013年第4期29卷 387-392页

作者： fu Wang jun Zhang Taiwen Huang Lin Liu Hengzhi fu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

The mechanisms of grain refinement were investigated on two kinds of grain refiners used in Ni-Fe based superalloys and complete atomic matching modes were constructed in this study. It is found that there are at least three matching crystal planes having the small lattice disregistry between the refiner and the nucleated phase, which can lead to grain refinement of γ matrix. The results indicate that the （0001）, （01-10） planes of CrFeNb have a fine crystallographic matching relationship with the （111）, （110） planes of γ matrix. The disregistry of （0001）CrFeNb//（111 ）γ, （011-0）CrFeNb//（111）γ and （0110）CrFeNb//（110）γ is 3.34%, 6.60% and 5.90%, respectively. The （0001）, （0110） planes of Co3FeNb2 and （111）, （110） planes of γ matrix also have this relationship. The disregistry of （0001）Co3FeNb2//（111）γ, （0001）Co3FeNb2//（110）γ, （0110）Co3FeNb2//（111）γ and （0110）Co3FeNb2//（110）γ, is 4.45%, 9.35%, 8.38% and 6.12%, respectively.

关键词： Grain refinement Growth mechanism Superalloy Solidification

Pacific oyster(Crassostrea gigas)shell growth duration in a year in Bohai Bay and implication for its carbon sink potential

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China Geology 2024年第4期7卷 653-660页

作者： Wen-yu Wang Chang-fu Fan Zhao-jun Song Hong Wang fu Wang Qingdao Geotechnical Investigation and Surveying Research Institute Qingdao 266033China MRL Key laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Tianjin Centre China Geological SurveyTianjin 300170China

Oyster is a bivalve mollusk widely distributed in estuarine and shallow sea *** growth and burial process is a carbon sequestration and storage *** shell may stop growing due to suffer from freeze shock during the winter season within a temperate climate,therefore,in order to study the carbon sequestration capacity of oysters we need to know the water temperature at which the shell suffer from winter freeze *** study examinesδ^(18)O profiles across consecutive micro-growth layers found in three modern Pacific oyster shells from the northwest coast of Bohai Bay.A total of 165 oxygen isotope values from sequential samples of their left shells showed periodically varying values,and the variation fluctuation of oxygen isotope values was 4.97‰on *** to the variation range of the oxygen isotope value of the shell,combined with the sea surface temperature and the sea surface salinity data of the water in which the oysters grew,the water temperature that suffer from winter freeze shock and stops or retards the growth of Pacific oysters in Bohai Bay is about 8.3℃,and the corresponding period is from December to March of the following *** calcification time of oysters within one year is nearly a month longer than previously thought,therefore,its carbon sink potential is also improved.

关键词： Crassostrea gigas Winter freeze shock Oxygen isotope Bohai Bay Carbon sequestration and storage Environmental geological survey