Numerical and experimental analysis of a counter-rotating type horizontal-axis tidal turbine

Bin Huang,Yuji Nakanishi,Toshiaki Kanemoto 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.2

In order to exploit renewable energies form tidal currents, a unique counter-rotating type horizontal-axis tidal turbine was proposed in this paper. Although a counter-rotating type horizontal-axis wind turbine can be taken as a reference in designing the proposed counterrotating tidal turbine, there are some different characteristics such as the effects of the free surface and the occurrence of cavitation. The unique tidal turbine in this paper was preliminarily designed on the basis of the in-house wind turbine, and then CFD analysis and experimental test were carried out to evaluate its performance. For the extreme conditions where severe flow separation and vortex exist, the comparison of the power coefficients generated by the turbine between the CFD predictions and the experimental data shows not so good. However, good agreement has been obtained for the comfortable blade pitch setting angles and over a range of tip speed ratios, which provides an evidence of validation of CFD analysis. Such results give sufficient confidence that the CFD model set up here is suitable for the further works.

Superhydrophobic and smart MgAl-LDH anti-corrosion coating on AZ31 Mg surface

Manyi Huang,Guangming Lu,Jibin Pu,Yujie Qiang 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.103 No.-

Layered double hydroxides (LDHs) have been widely used as ‘‘smart” containers in the field of metal corrosionprotection, and have broad industrial prospects. It is environmentally friendly and feasible to usealiphatic carboxylates and corresponding acids as substitutes for harmful corrosion inhibitors. However,previous studies rarely involved comparing the anti-corrosion mechanisms of different aliphatic acidsmodified on the LDH surface, and the durability of the prepared coatings also needs to be improved. Inthis work, MgAl-LDH laminates were grown in situ on AZ31 substrates by a hydrothermal method,and then modified by sodium laurate (SL) and sodium dodecylbenzene sulfonate (SDBS). Due to the physicalbarrier effect of the LDH layers, the spatial repulsion effect of the air film and the ion exchange reactionsin the interlayer galleries, the functional coatings prepared exhibit smart and superior anticorrosionperformance on the magnesium substrates in 3.5 wt.% NaCl solution. Compared with LDHSDBS-8 coating, the obtained superhydrophobic LDH-SL-8 coating shows more excellent long-term corrosionprotection owing to the stronger intercalation capacity.

<i>SWIFT</i> GRB GRB071010B: OUTLIER OF THE <i>E</i>^src_peak - <i>E</i>_γ AND <i>E</i>_iso - <i>E</i>^src_peak - <i>t</i>^src_jet CORRELATIONS

Urata, Yuji,Huang, Kuiyun,Im, Myungshin,Lee, Induk,Deng, Jinsong,Ip, WingHuen,Krimm, Hans,Liping, Xin,Ohno, Masanori,Qiu, Yulei,Sugita, Satoshi,Tashiro, Makoto,Wei, Jianyan,Yamaoka, Kazutaka,Zheng, We IOP Publishing 2009 ASTROPHYSICAL JOURNAL LETTERS - Vol.706 No.1

<P>We present multi-band results for GRB071010B based on Swift, Suzaku, and ground-based optical observations. This burst is an ideal target to evaluate the robustness of the E-peak(src) - E-iso and E-peak(src) - E-gamma relations, whose studies have been in stagnation due to the lack of the combined estimation of E-peak(src) and long-term optical monitoring. The joint prompt spectral fitting using Swift/Burst Alert Telescope and Suzaku/Wide-band All-sky Monitor data yielded the spectral peak energy as E-peak(src) of 86.5(-6.3)(+6.4) keV and E-iso of 2.25(-0.16)(+0.19) x 10(52) erg with z = 0.947. The optical afterglow light curve is well fitted by a simple power law with temporal index alpha = -0.60 +/- 0.02. The lower limit of temporal break in the optical light curve is 9.8 days. Our multi-wavelength analysis reveals that GRB071010B follows E-peak(src) - E-iso but violates the E-peak(src) - E-gamma and E-iso - E-peak(src) - t(jet)(src) at more than the 3 sigma level.</P>

SYNCHROTRON SELF-INVERSE COMPTON RADIATION FROM REVERSE SHOCK ON GRB 120326A

Urata, Yuji,Huang, Kuiyun,Takahashi, Satoko,Im, Myungshin,Yamaoka, Kazutaka,Tashiro, Makoto,Kim, Jae-Woo,Jang, Minsung,Pak, Soojong IOP Publishing 2014 The Astrophysical journal Vol.789 No.2

<P>We present multi-wavelength observations of a typical long duration GRB 120326A at z = 1.798, including rapid observations using a Submillimeter Array (SMA) and a comprehensive monitoring in the X-ray and optical. The SMA observation provided the fastest detection to date among seven submillimeter afterglows at 230 GHz. The prompt spectral analysis, using Swift and Suzaku, yielded a spectral peak energy of E-peak(src) = 107.8(- 15.3)(+15.3) keV and an equivalent isotropic energy of E-iso as 3.18(-0.32)(+0.40) x 10(52) erg. The temporal evolution and spectral properties in the optical were consistent with the standard forward shock synchrotron with jet collimation (6 degrees.69 +/- 0 degrees.16). The forward shock modeling, using a two-dimensional relativistic hydrodynamic jet simulation, was also determined by the reasonable burst explosion and the synchrotron radiation parameters for the optical afterglow. The X-ray light curve showed no apparent jet break and the temporal decay index relation between the X-ray and optical (alpha o - alpha x = -1.45 +/- 0.10) indicated different radiation processes in each of them. Introducing synchrotron self-inverse Compton radiation from reverse shock is a possible solution, and the detection and slow decay of the afterglow in submillimeter supports that this is a plausible idea. The observed temporal evolution and spectral properties, as well as forward shock modeling parameters, enabled us to determine reasonable functions to describe the afterglow properties. Because half of the events share similar properties in the X- ray and optical as the current event, GRB 120326A will be a benchmark with further rapid follow-ups, using submillimeter instruments such as an SMA and the Atacama Large Millimeter/submillimeter Array.</P>

Property Assessment of High-Performance Concrete Containing Three Types of Fibers

Hua Huang,Yujie Yuan,Wei Zhang,Liang Zhu 한국콘크리트학회 2021 International Journal of Concrete Structures and M Vol.15 No.6

This study investigated the mechanical properties and the effects of the volume fraction for carbon fibers (CF-VF), polypropylene fibers (PPF-VF) and aramid fibers (AF-VF) with a fixed aspect ratio of 650 for the carbon fibers, 400 for the polypropylene fibers and 900 for the aramid fibers in hybrid fiber-reinforced concrete (HFRC). Furthermore, compressive, splitting tensile and flexural tensile tests were carried out to obtain the optimal total volume fraction for the three types of fibers, as well as the optimal ratio between the CF-VF, PPF-VF and AF-VF. In addition, stress-strain curves of normal concrete and HFRC were examined to explore the whole mechanical process. The results indicated the CF-VF, PPF-VF and AF-VF have a significant effect on the tensile and flexural strengths of HFRC. The HFRC with a fiber additional ratio of 25:50:25 had the best hybrid effect. Moreover, a calculation method based on the compressive strength of normal concrete and HFRC and the volume fraction is proposed to calculate the strength of HFRC in engineering as a reference. Besides, a uniaxial compression constitutive mathematical model of normal concrete and HFRC is established.

Field measurement and numerical simulation of excavation damaged zone in a 2000 m-deep cavern

Zhang, Yuting,Ding, Xiuli,Huang, Shuling,Qin, Yang,Li, Peng,Li, Yujie Techno-Press 2018 Geomechanics & engineering Vol.16 No.4

This paper addresses the issue of field measurement of excavation damage zone (EDZ) and its numerical simulation method considering both excavation unloading and blasting load effects. Firstly, a 2000 m-deep rock cavern in China is focused. A detailed analysis is conducted on the field measurement data regarding the mechanical response of rock masses subjected to excavation and blasting operation. The extent of EDZ is revealed 3.6 m-4.0 m, accounting for 28.6% of the cavern span, so it is significantly larger than rock caverns at conventional overburden depth. The rock mass mechanical response subjected to excavation and blasting is time-independent. Afterwards, based on findings of the field measurement data, a numerical evaluation method for EDZ determination considering both excavation unloading and blasting load effects is presented. The basic idea and general procedures are illustrated. It features a calibration operation of damage constant, which is defined in an elasto-plastic damage constitutive model, and a regression process of blasting load using field blasting vibration monitoring data. The numerical simulation results are basically consistent with the field measurement results. Further, some issues regarding the blasting loads, applicability of proposed numerical method, and some other factors are discussed. In conclusion, the field measurement data collected from the 2000 m-deep rock cavern and the corresponding findings will broaden the understanding of tunnel behavior subjected to excavation and blasting at great depth. Meanwhile, the presented numerical simulation method for EDZ determination considering both excavation unloading and blasting load effects can be used to evaluate rock caverns with similar characteristics.

Design and optimization of novel transceiver device for one‑way single‑wire power transfer

Yang Li,Taocheng Hu,Xueliang Wang,Yujie Zhai,Yao Li,Wenxin Huang,Zhigang Lou 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.10

The further development of wireless power transfer technology is hindered by the limiting relationship between transmission distance, transmission efficiency, and size of the coupling mechanism. Thus, a feasible solution was provided by one-way single-wire power transfer. First, a horn-type mode conversion device was proposed in this study by analyzing the principle of one-way single-wire power transfer. Second, the system structure was designed to save materials and reduce the volume of space. The transmission efficiency of the system was improved, and the operating frequency was reduced by optimizing the parameters of the mode conversion device. Finally, the feasibility and structural applicability of the one-way single-wire power transfer method proposed in this study were proved by the experimental results.

Simultaneous separation of three isoflavones on oligo-β-cyclodextrin substituted polystyrene-based medium and evaluation adsorption characteristics using AutoDock

Li Yang,Tianwei Tan,Jinyi Luan,Xin Wei,Yongqiang Yang,Wenqing Huang,Zhi Guo,Yujie Wang 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.2

The adsorption characteristics between three isoflavones in crude soybean sample and styrene-β-cyclodextrin (S-CD) were studied by molecular mechanics calculations with AutoDock. The discriminatory ability exhibited by S-CD against glycitin, daidzin, and genistin through the differences in the interaction energies and complex geometries could potentially serve for the chromatographic separation. The chromatographic elution order of the three analytes on oligo-β-cyclodextrin substituted polystyrene-based medium (PS-CDP) was predicted depending on the binding free energy values obtained from molecular docking simulations. The experimental results of chromatographic evaluation on PS-CDP were consistent with the simulation prediction. The three isoflavones in sample can be simultaneously separated in one-step under the optimized mobile phase, which consisted of methanol/0.1mM NH4AC=65.0/35.0 (v/v) by PS-CDP column chromatography. A glycitin purity of 95.1% with a recovery of approximate 86.3% was achieved by proper peak cutting, and that of daidzin and genistin was 95.8%, 95.4% and 96.2%, 95.7%, respectively.

Recent developments in the field of dehydration of bio-renewable glycerol to acrolein over molecular sieve catalysts

Tianlin Ma,Manyun Yin,Chunyang Su,Ningfei Guo,Xiangxiang Huang,Zhen Han,Yujie Wang,Gangling Chen,Zhi Yun 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.117 No.-

The surplus production of glycerol as a byproduct of biodiesel has become an urgent problem for the sustainabilityof the biodiesel industry. The catalytic transformation of glycerol to value-added chemicalshas attracted the attention of researchers worldwide over the last decade. Among them, selective dehydrationof glycerol to acrolein has gained interest from both academic researchers and industrial applications. Molecular sieves have been considered as the most promising catalysts for industrialapplications of glycerol dehydration. However, there is no systematic summary for the research carriedout for this reaction over molecular sieve catalysts. This work provides a comprehensive and criticalreview of glycerol dehydration to acrolein over molecular sieve catalysts, including ZSM-5, ZSM-11,MCM-22, MCM-41, SBA-15, SAPO-34, HY and Hb. The key technical problems that restrict its industrialapplication are the easy coking and poor stability of the molecular sieves. In particular, the pore size, porestructure, acid amount, acid strength, acid type and reaction conditions that influence the dehydrationperformance are discussed in detail. Furthermore, the reaction mechanism, reaction kinetics, reactionthermodynamics and future research directions for catalyst design and engineering are also presented. This review will deepen our understanding of the catalytic dehydration of glycerol to acrolein and provideguidance for researchers on the rational design of molecular sieve catalysts.

ROS-activated CXCR2+ neutrophils recruited by CXCL1 delay denervated skeletal muscle atrophy and undergo P53-mediated apoptosis

Xiang Yaoxian,Dai Junxi,Li Yao,You Zongqi,Zhang Junpeng,Huang Xinying,Nie Shuqi,Chen Yujie,Xu Lei,Liu Fengming,Jiang Junjian,Xu Jianguang 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Neutrophils are the earliest master inflammatory regulator cells recruited to target tissues after direct infection or injury. Although inflammatory factors are present in muscle that has been indirectly disturbed by peripheral nerve injury, whether neutrophils are present and play a role in the associated inflammatory process remains unclear. Here, intravital imaging analysis using spinning-disk confocal intravital microscopy was employed to dynamically identify neutrophils in denervated muscle. Slice digital scanning and 3D-view reconstruction analyses demonstrated that neutrophils escape from vessels and migrate into denervated muscle tissue. Analyses using reactive oxygen species (ROS) inhibitors and flow cytometry demonstrated that enhanced ROS activate neutrophils after denervation. Transcriptome analysis revealed that the vast majority of neutrophils in denervated muscle were of the CXCR2 subtype and were recruited by CXCL1. Most of these cells gradually disappeared within 1 week via P53-mediated apoptosis. Experiments using specific blockers confirmed that neutrophils slow the process of denervated muscle atrophy. Collectively, these results indicate that activated neutrophils are recruited via chemotaxis to muscle tissue that has been indirectly damaged by denervation, where they function in delaying atrophy.