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Adaptive rotor current control for wind-turbine driven DFIG using resonant controllers in a rotor rotating reference frame

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 149-155页

作者： jia-bing hu Yi-kang HE Hong-sheng WANG School of Electrical Engineering Zhejiang University Hangzhou 310027 China

This paper proposes an adaptive rotor current controller for doubly-fed induction generator (DFIG), which consists of a proportional (P) controller and two harmonic resonant (R) controllers implemented in the rotor rotating reference frame. The two resonant controllers are tuned at slip frequencies ωslip+ and ωslip-, respectively. As a result, the positive- and negative-sequence components of the rotor current are fully regulated by the PR controller without involving the positive- and negative-sequence decomposition, which in effect improves the fault ride-through (FRT) capability of the DFIG-based wind power generation system during the period of large transient grid voltage unbalance. Correctness of the theoretical analysis and feasibility of the proposed unbalanced control scheme are validated by simulation on a 1.5-MW DFIG wind power generation system.

关键词： Unbalanced grid voltage Doubly-fed induction generator (DFIG) Proportional plus Resonant (PR) controller Faultride-through (FRT)

Proportional integral plus multi-frequency resonant current controller for grid-connected voltage source converter under imbalanced and distorted supply voltage conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1532-1540页

作者： jia-bing hu Wei ZHANG Hong-sheng WANG Yi-kang HE Lie XU School of Electrical Engineering Zhejiang University Hangzhou 310027 China Department of Electronics and Electrical Engineering Strathclyde University Glasgow G1 1XW UK

This paper proposes a current control scheme for a grid-connected pulse width modulator(PWM) voltage source converter(GC-VSC) under imbalanced and distorted supply voltage *** control scheme is implemented in the positive synchronously rotating reference frame and composed of a single proportional integral(PI) regulator and multi-frequency resonant controllers tuned at the frequencies of 2ω and 6ω,*** experimental results,with the target of eliminating the active power oscillations and current harmonics on a prototype GC-VSC system,validate the feasibility of the proposed current control scheme during supply voltage imbalance and distortion.

关键词： Grid-connected voltage source converter (GC-VSC) Proportional integral plus multi-frequency resonant (PI+MFR) Imbalance Harmonics distortion

Synthesis of a Novel UV Curable Aqueous Dispersion Polyurethane PDHA-PEDA-PU and the Properties of Cured Film

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Chinese Chemical Letters 2006年第3期17卷 369-372页

作者： Chen Yan BAI Xing Yuan ZHANG jia bing DAI Wei hu LI Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026

A novel ultraviolet （UV） curable aqueous dispersion polyurethane PDHA-PEDA-PU was synthesized based on isophorone diisocyanate （IPDI）, polyester dihydric alcohol （PDHA）, dimethylol propionic acid （DMPA）, pentaerythritol diacrylate （PEDA）, 2-hydroxyethyl acrylate （HEA） and triethylamine （TEA）. Acrylate groups were incorporated in the side and end of PDHA-PEDA-PU chain. The C=C content in the chain can be controlled easily through the change of IPDI/PDHA/PEDA ratio. Fourier transform infrared spectroscopy （FTIR） was used to identify the structure of prepolymer, aqueous dispersion and cured polyurethane. The curing rule of the polyurethane for different C=C content has been investigated depending on the change of C=C content during the curing process. The hardness, thermal stability and scrub resistance to MEK of UV cured PDHA-PEDA-PU were also discussed for the samples with different C=C content.

关键词： UV curable aqueous dispersion polyurethane

Ultrasonography in predicting and screening liver cirrhosis in children:A preliminary study

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World Journal of Gastroenterology 2003年第10期9卷 2348-2349页

作者： jia-An Zhu bing hu, Department of Ultrasound in Medicine, Affiliated Sixth People’s Hospital, Shanghai jiaotong University, Shanghai 200233, China Department of Ultrasound in Medicine Shanghai Sixth People's Hospital Shanghai Jiaotong University Shanghai 200233 China. zhujiaan@***

AIM: To evaluate the value of ultrasonography in predicting and screening liver cirrhosis in ***: Twenty-eight children with liver cirrhosis of various etiologies were examined by routine ultrasonography.A percutaneous liver biopsy guided by ultrasound was also performed on each patient, and the results of liver biopsy and ultrasonography were ***: When compared with the biopsy results,ultrasonography in combination of clinical and laboratory findings gave accurate diagnoses of children liver *** ultrasound imaging of children with liver cirrhosis revealed abnormal characteristics, these images were not specific to this disease, thus reinforcing the necessity of ultrasound-guided liver biopsy in the diagnosis of children liver ***: Ultrasonography is reliable in the diagnosis of children liver cirrhosis, and its usefulness should be stressed in the screening and follow-up of high-risk pediatric patients.

关键词：肝硬化儿童诊断超声检查活组织检查

Numerical investigation of the nonlinear spectral broadening aiming at a few-cycle regime for 10 ps level Nd-doped lasers

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Chinese Physics B 2022年第9期31卷 320-325页

作者： Xi-Hang Yang Fen-Xiang Wu Yi Xu jia-bing hu Pei-Le Bai Hai-Dong Chen Xun Chen Yu-Xin Leng Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

We present a cascaded nonlinear spectral broadening scheme for Nd-doped lasers,featuring with long pulse duration and high average *** scheme is based on two multi-pass cells(MPCs)and one multiple-plate supercontinuum generation(MPSG),and the numerical investigation is driven by a home-made Nd-doped fiber laser with 12 ps pulse duration,50 kHz repetition rate and 100 W average *** MPC-based first two stages allow us to broaden the pulse spectrum to 4 nm and 43 nm respectively,and subsequently,the MPSG-based third stage allows us to reach 235 nm spectral *** broadened spectrum can support a Fourier-transfer-limited pulse duration of 9.8 fs,which is shorter than three optical *** the best of our knowledge,it is the first time to demonstrate the possibility of few-cycle pulses generation based on the 10 ps level Nd-doped *** few-cycle and high average power laser sources should be attractive and prospective,benefiting from the characteristics of structure compact,low-cost and flexibility.

关键词： nonlinear spectral broadening picosecond lasers high average power

Mechanism by which Rab5 promotes regeneration and functional recovery of zebrafish Mauthner axons

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Neural Regeneration Research 2025年第6期20卷 1816-1824页

作者： jiantao Cui Yueru Shen Zheng Song Dinggang Fan bing hu Center for Advanced Interdisciplinary Science and Biomedicine of IHM Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina

Rab5 is a GTPase protein that is involved in intracellular membrane trafficking. It functions by binding to various effector proteins and regulating cellular responses, including the formation of transport vesicles and their fusion with the cellular membrane. Rab5 has been reported to play an important role in the development of the zebrafish embryo;however, its role in axonal regeneration in the central nervous system remains unclear. In this study, we established a zebrafish Mauthner cell model of axonal injury using single-cell electroporation and two-photon axotomy techniques. We found that overexpression of Rab5 in single Mauthner cells promoted marked axonal regeneration and increased the number of intra-axonal transport vesicles. In contrast, treatment of zebrafish larvae with the Rab kinase inhibitor CID-1067700markedly inhibited axonal regeneration in Mauthner cells. We also found that Rab5 activated phosphatidylinositol 3-kinase(PI3K) during axonal repair of Mauthner cells and promoted the recovery of zebrafish locomotor function. Additionally, rapamycin, an inhibitor of the mechanistic target of rapamycin downstream of PI3K, markedly hindered axonal regeneration. These findings suggest that Rab5 promotes the axonal regeneration of injured zebrafish Mauthner cells by activating the PI3K signaling pathway.

关键词： axonal regeneration Mauthner cell nerve regeneration Rab5 zebrafish

Continuous high-temperature rapid nanomanufacturing of electrocatalysts

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Nano Research 2025年第1期18卷 225-235页

作者： Xiaoyang Wang Ziyi Luo Baihua Cui Ziqi Fu Yanchang Liu Weidi Liu jia Ding jianrong Zeng Yanan ChenWenbin hu School of Materials Science and Engineering Tianjin UniversityTianjin 300350China Australian Institute for Bioengineering and Nanotechnology The University of QueenslandSt.LuciaBrisbane 4072Australia Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

Encapsulating metal nanoparticles in carbon shells(Metal@C)to enhance catalytic activity and stability has been certified ***,most existing methods for preparing Metal@C are complex,time-consuming,and lack of *** this study,a novel method that couples the high-temperature shock(HTS)with ultrasonic spray pyrolysis is reported,which can realize facile and scalable production of various Metal@C through the pyrolysis of glucose and metal chloride *** proposed HTS ultrasonic spray pyrolysis offers several advantages,including compact size,short reaction time(~120 ms),and uniform *** the Ni@C-40 nanocomposite as an example,the ultrasmall Ni nanoparticles(~10 nm)with thin carbon protective shells(~2 nm)are uniformly dispersed in the carbon matrix and applied for oxygen evolution reaction(OER)in alkaline *** Ni@C-40 optimized by tuning the thickness of carbon shell exhibits significantly enhanced OER activity with low overpotential of 242 mV at 10 mA·cm^(-2) and stability,which is attributed to the optimized interactions between Ni nanoparticles and carbon *** method also shows promise for continuous pyrolysis synthesis of various extreme materials at ultra-high temperatures using alternative electric heating materials.

关键词： ultrasonic spray pyrolysis high-temperature shock carbon shell oxygen evolution reaction Metal@C nanocomposite

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng Wang Qinyi Guo Bin hu Haiwen Luo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

Janus MXene film with gradient structure for highly efficient terahertz and infrared electromagnetic absorption

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Nano Research 2025年第1期18卷 434-442页

作者： Shaodian Yang Weiqiang huang Zhiqiang Lin Zibo Chen Rongliang Yang Yi jia Xuebin Liu Rui Wang Zhiping Zeng Yougen hu huanjun Chen Xuchun Gui11 State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China National Key Laboratory of Materials for Integrated Circuits Shenzhen Institute of Advanced Electronic MaterialsShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China China Academy of Aerospace Science and Innovation Beijing 100176China Guangdong Province Key Laboratory of Display Material and Technology Guangzhou 510275China School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China

Electromagnetic interference (EMI) shielding inhigh-frequency range, especially the rapidly growing terahertz(THz) frequency range, attracts increasing attention due tothe potential application of terahertz in 6G wirelesscommunication, and security inspection. However, traditionalconductive EMI films typically achieve high shieldingeffectiveness through strong reflection, which may causesecondary pollution to other devices. Here, a gradientstructure strategy was proposed to constructTi_(3)C_(2)Tx/hydroxypropyl methyl cellulose (HPMC) film, in whichthe content of Ti_(3)C_(2)Tx gradually increases along the thicknessdirection, resulting in different conductivity of the two surfaces(surface-M and surface-H) for the film. The obtained gradientfilmexhibits an EMI shielding efficiency of over 48.5 dB in theTHz range (0.2-1.6 THz) at a thickness of 40 μm. Especially,as the THz waves incident from the surface-H to the film, the absorption effectiveness reaches 48.2 dB (average absorbedpower loss up to 91.4%), and the reflection effectiveness is only 0.3 dB. In additions, the gradient-film also demonstrates ahigh absorption rate of 95.5% in the infrared band (2.5-16.7 μm). Moreover, the gradient-film exhibits an excellent tensilestress and Young’s modulus value of 173.1 MPa and 2.8 GPa, respectively. Therefore, the gradient-film proposed in thiswork, with excellent electromagnetic absorption in both THz and infrared band, provides a promising candidate for the nextgenerationEMI shielding applications.

关键词： electromagnetic interference shielding Janus film terahertz MXene