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Reliability Analysis of Grid-Interfaced Filter Capacitors

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Chinese Journal of Electrical Engineering 2018年第3期4卷 21-28页

作者： dao Zhou Haoran wang Huai wang Frede Blaabjerg Department of Energy Technology Aalborg UniversityAalborg9220Denmark

Growing with the increased adoption of renewable energy for the power generation,the reliable and cost-effective operation of grid-connected inverters is of more and more importance.A filter is interfaced between an inverter and the utility grid to reduce the switching *** to the modulation scheme and the LCL filter impedance,the electrical stresses of the filter capacitor can be thoroughly *** the help of the electro-thermal model,its long-term thermal stress can be obtained based on the mission profile like wind speed,ambient *** reliability of the filter capacitor bank is obtained based on its individual capacitor reliability curves and reliability block diagram method.A case study on a 2MW wind turbine system demonstrates the relationship between the lifetime of the capacitor bank and the single ***,the severe voltage and current stresses of the filter capacitors are analyzed during abnormal operations(e.g.,fault ride-through)with asymmetrical parasitic parameters.

关键词： Metalized polypropylene film capacitor reliability doubly-fed induction generator fault ride-through

Nondestructive Nonlinear Optical Microscopy Revealed the Blackening Mechanism of Ancient Chinese Jades

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Research 2024年第3期2023卷 391-399页

作者： Yaxin Chen rong wang Minbiao Ji State Key Laboratory of Surface Physics and Department of Physics Human Phenome InstituteAcademy for Engineering and TechnologyKey Laboratory of Micro and Nano Photonic Structures(Ministry of Education)Yiwu Research Institute of Fudan UniversityFudan UniversityShanghai 200433China Department of Cultural Heritage and Museology Fudan UniversityShanghaiChina

Jade is most valued in Chinese culture since ancient times. For unearthed jade artifacts, the alteration color resulting from weathering effects and human activities provides information for cultural heritage conservation, archaeology, and history. Currently, the noninvasive 3-dimensional characterization of jade artifacts with high chemical and spatial resolution remains challenging. In this work, we applied femtosecond pump–probe microscopy and second harmonic generation microscopy techniques to study the black alteration of an ancient jade artifact of the late Spring and Autumn period (546 to 476 BC). The direct cause of the “mercury alteration” phenomena was discovered to be the conversion of metacinnabar from buried cinnabar in the tomb. Furthermore, a 3-dimensional optical reconstruction of the black alteration was achieved, providing a high-resolution method for analyzing the blackening mechanism without the need of sample damage. Our approach opens up new opportunities to extract microscopic spatiochemical information for a broad range of alteration colors in jade artifacts.

关键词： pump Nonlinear buried

Wellposedness for anisotropic rotating fluid equations

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Applied Mathematics(A Journal of Chinese Universities) 2012年第1期27卷 9-33页

作者： FANG dao-yuan wang Su-mei ZHANG Ting Department of Mathematics Zhejiang UniversityHangzhou 310027China

The weUposedness problem for an anisotropic incompressible viscous fluid in R3, ro- tating around a vector B（t, x）：= （b1 （t, x）, b2 （t, x）, b3 （t, x））, is studied. The global wellposedness in the homogeneous case （B = e3） with sufficiently fast rotation in the space B0,1/2 is proved. In the inhomogeneous case （B = B（t, xh））, the global existence and uniqueness of the solution in B0,1/2 are obtained, provided that the initial data are sufficient small compared to the horizontal viscosity. Furthermore, we obtain uniform local existence and uniqueness of the solution in the x same function space. We also obtain propagation of the regularity in B2,11/2 under the additional assumption that B depends only on one horizontal space variable.

关键词： the anisotropic Navier-Stokes-Coriolis equation wellposedness anisotropic.

VCR-LFM-BPSK signal design for countering advanced interception technologies

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Journal of Systems Engineering and Electronics 2021年第2期32卷 380-388页

作者： wang Shanshan LIU Zheng XIE rong wang Jingjing National Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China

The hybrid waveform of linear frequency modulation and binary phase shift keying(LFM-BPSK)can take advantages of the LFM and BPSK signals,and reduce the defects of ***,with the development of interception technology for the LFM-BPSK signal,the application of the signal is *** this paper,to improve the anti-interception performance of the hybrid waveform,a new waveform of LFM-BPSK with the varying chirp rate(denoted as VCR-LFM-BPSK)is *** this design,based on the working principle of the interception frame for the LFM-BPSK signal,different chirp rates are introduced in different sub-pulses to prevent the signal from being intercepted by the ***,to further improve the anti-interception performance of the VCR-LFM-BPSK signal,the chirp rates are optimized by minimizing the interception capability of the ***,based on the VCR-LFM-BPSK signal with the optimized chirp rates,the binary phases are designed via a multiobjective Pareto optimization to improve the capabilities of autocorrelation and *** results demonstrate that the designed VCR-LFM-BPSK signal outperforms the traditional LFM-BPSK signal in countering the advanced interception technologies.

关键词： hybrid waveform waveform design anti-interception optimization

Influences of Charcoal Amendment on Adsorption-Desorption of Isoproturon in Soils

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Agricultural Sciences in China 2010年第2期9卷 257-265页

作者： TIAN Chao wang Mi-dao SI You-bin School of Sciences Anhui Agricultural University Hefei 230036 P.R.China School of Resources and Environment Anhui Agricultural University Hefei 230036 P.R.China

In order to prevent pesticide leaching from soil, the effects of charcoal amendment on adsorption-desorption of isoproturon in soils were studied and the mechanisms in reducing the loss of isoproturon from soils were suggested. Adsorption-desorption of isoproturon in five different particle sizes of charcoals and three different soils were studied using batch equilibration technique. The results showed that the experimental data were well fitted by the Freundlich empirical equation. Charcoal had a great adsorption capacity for isoproturon, and the smaller the particle size of charcoal, the more the adsorption of isoproturon. The amendment with charcoal could greatly improve the adsorption of isoproturon in soils. The adsorption of isoproturon in soils increased with the rate of charcoal amended （r= 0.9568＊＊, P 〈 0.01）. Desorption of isoproturon from charcoals and soils showed significant hystersis which was shown by the higher adsorption slope （1/nsds） compared to the desorption slope （1/ndes. The hysteresis effects of charcoal on desorption of isoproturon were closely correlated with the content of charcoal in the soils, and the hysteresis index （H） increased with the rate of charcoal amended. Observation of environmental scanning electron microscopy （ESEM） exhibitted the fine pore structure and special surface characteristics of the tested charcoal. Analysis of Fourier transform infrared spectra （FTIR） of isoproturon adsorbed on charcoal suggested probable bonding interactions between isoproturon and charcoal. This research suggests that charcoal amendment may be an effective management practice for controlling pesticide desorption and leaching in soils.

关键词： charcoal amendment isoproturon adsorption desorption soil

A refined trans-Planckian censorship conjecture

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Science China(Physics,Mechanics & Astronomy) 2021年第1期64卷 33-40页

作者： rong-Gen Cai Shao-Jiang wang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing100190China Tufts Institute of Cosmology Department of Physics and AstronomyTufts UniversityMedford02155USA

We propose a refined version of trans-Planckian censorship conjecture(TCC), which could be elaborated from the strong scalar weak gravity conjecture combined with some entropy bounds. In particular, no fine-tuning on the inflation model-building is required in the refined TCC, and it automatically passes the tests from those stringy examples that support the original ***, our refined TCC could be consistent with hilltop eternal inflation.

关键词： inflation swampland conjectures weak gravity conjecture

C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2231-2244页

作者： Xiangzi wang Xiaofei Niu Yingkai wang Yang Liu Cheng Yang Xuyi Chen Zhongquan Qi School of Medicine Guangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Graduate School of Tianjin University of Traditional Chinese Medicine TianjinChina Characteristic Medical Center of People’s Armed Police Forces TianjinChina Fujian Maternity and Child Health Hospital FuzhouFujian ProvinceChina

Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory *** expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after *** studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for *** review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord ***,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted ***,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.

关键词： apoptosis C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway C-C motif chemokine receptor 2 antagonists chemokine ligand 2 chemokine receptor 2 inflammation macrophage microglia spinal cord injury therapeutic method

Effect of CeO_2 preparation method and Cu loading on CuO/CeO_2 catalysts for methane combustion

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Journal of Natural Gas Chemistry 2009年第4期18卷 458-466页

作者： Weiling Yang dao Li Dongmei Xu Xingyi wang Key Laboratory for Advanced Materials Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237 China

CeO2 was synthesized by sol-gel, hydrothermal, nitrate thermal decomposition methods, respectively, and used as support to prepare CuO/CeO2 catalysts. According to characterization and reaction results, preparation method of CeO2 had a great influence on the physicochemical properties and activities of CuO/CeO2 catalysts. CuO with high dispersion and strong interaction with CeO2 was highly active in methane combustion, while CuO particles less associated with CeO2 showed less activity. The CuO catalyst supported on CeO2 which was prepared via nitrate thermal decomposition method showed the largest area, the smallest particle size, the highest dispersion of copper species and strong support metal interactions. Therefore, it presented the highest redox ability and activity for methane combustion. Activities of the catalysts with different copper content kept increasing until 5% Cu loading and from then on kept constant. Moreover, methane conversion decreased as methane space velocities increased on CuO/CeO2 catalyst. Addition of CO2 to the feed did not produce a significant effect on the catalytic activity, but the presence of H2O provoked a remarkable decrease on the activity of CuO/CeO2 catalyst.

关键词： ceria CuO/Ce02 methane combustion

Growth differentiation factor 15 predicts cardiovascular events in stable coronary artery disease

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Journal of Geriatric Cardiology 2023年第7期20卷 527-537页

作者： Juan wang Li-Na HAN dao-Sheng AI Xin-Yu wang Wan-Jing ZHANG Xiao-rong XU Hong-Bin LIU Jing ZHANG Pan wang Xu LI Mu-Lei CHEN Heart Center of Beijing Chao-Yang Hospital Capital Medical UniversityBeijing Key Laboratory of HypertensionBeijingChina Department of Cardiology the Second Medical CenterNational Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijingChina Academy for Advanced Interdisciplinary Studies Peking University National Institute of Biological SciencesZhongguancun Life Science ParkTsinghua UniversityBeijingChina

BACKGROUND Growth differentiation factor 15(GDF-15)has been explored as a potential biomarker for various inflammatory diseases and cardiovascular *** study aimed to assess the predictive role of GDF-15 levels in cardiovascular events and all-cause mortality,considering traditional risk factors and other *** A prospective study was conducted and 3699 patients with stable coronary artery disease(CAD)were enrolled into the *** GDF-15 levels were *** follow-up was 3.1 years during the *** analyzed clinical variables and several *** Cox regression analysis was performed to evaluate prognostic performance of GDF-15 levels in predicting myocardial infarction(MI),heart failure,stroke,cardiovascular death,and non-cardiovascular *** Baseline GDF-15 levels for 3699 patients were grouped by quartile(≤1153,1153-1888,1888-3043,>3043 ng/L).Higher GDF-15 levels were associated with older age,male gender,history of hypertension,and elevated levels of N-terminal pro Btype natriuretic peptide(NT-pro BNP),soluble suppression of tumorigenesis-2(sST2),and creatine(each with P<0.001).Adjusting for established risk factors and biomarkers in Cox proportional hazards models,a 1 standard deviation(SD)increase in GDF-15 was associated with elevated risk of clinical events[hazard ratio(HR)=2.18,95%confidence interval(CI):(1.52-3.11)],including:MI[HR=2.8395%CI:(1.03-7.74)],heart failure[HR=2.7195%CI:(1.18-6.23)],cardiovascular and non-cardiovascular death[HR=2.48,95%CI(1.49-4.11)]during the median follow up of 3.1 *** Higher levels of GDF-15 consistently provides prognostic information for cardiovascular events and all cause death,independent of clinical risk factors and other ***-15 could be considered as a valuable addition to future risk prediction model in secondary prevention for predicting clinical events in patient with stable CAD.

关键词： cardiovascular elevated coronary