NDE Techniques of Fiber Characterization in Spar Caps of Wind Turbine Blades using Ultrasonic Waves

Xiao-Long Shia,Hua Liang,Zi-Heng Zhou,Peng Zhang,Gui-Lin Zhang,조영태,우용득,임광희 한국생산제조학회 2023 한국생산제조학회지 Vol.32 No.3

Recently, ultrasonic waves (UT) have attracted attention as a tool for nondestructive evaluation (NDE) in various fields, including agriculture, medical engineering, and airport security. In this study, carbon fiber reinforced plastic (CFRP) materials are inspected during the fabrication process. Ultrasonic techniques are commonly used to evaluate composites in spar caps of wind turbine blades. Therefore, the fiber orientation and defects of composites are investigated using one-sided ultrasonic measurements to evaluate the soundness of CFRP composites in spar caps of wind turbine blades. Compared with the ultrasonic pulse-echo method, the ultrasonic pitch-catch method is effective in the receiving ultrasonic signals on the composites. Ultrasonic signals must be controlled at arbitrary depths of CFRP composite laminates; this is called a “sampling volume.” Therefore, ultrasonic signals can be obtained at arbitrary depths of composites in any sampling volume.

Augmenter of Liver Regeneration Alleviates Renal Hypoxia-Reoxygenation Injury by Regulating Mitochondrial Dynamics in Renal Tubular Epithelial Cells

Xiao-hui Liao,Rui-ting Long,Jun-bo Peng,Li-li Huang,Gui-ping Jiang,Yue-juan Liao,Hang Sun,Yu-dong Hu 한국분자세포생물학회 2019 Molecules and cells Vol.42 No.12

Mitochondria are highly dynamic organelles that constantly undergo fission and fusion processes that closely related to their function. Disruption of mitochondrial dynamics has been demonstrated in acute kidney injury (AKI), which could eventually result in cell injury and death. Previously, we reported that augmenter of liver regeneration (ALR) alleviates renal tubular epithelial cell injury. Here, we gained further insights into whether the renoprotective roles of ALR are associated with mitochondrial dynamics. Changes in mitochondrial dynamics were examined in experimental models of renal ischemia-reperfusion (IR). In a model of hypoxia-reoxygenation (HR) injury in vitro, dynamin-related protein 1 (Drp1) and mitochondrial fission process protein 1 (MTFP1), two key proteins of mitochondrial fission, were downregulated in the Lv-ALR + HR group. ALR overexpression additionally had an impact on phosphorylation of Drp1 Ser637 during AKI. The inner membrane fusion protein, Optic Atrophy 1 (OPA1), was significantly increased whereas levels of outer membrane fusion proteins Mitofusin-1 and -2 (Mfn1, Mfn2) were not affected in the Lv-ALR + HR group, compared with the control group. Furthermore, the mTOR/4E-BP1 signaling pathway was highly activated in the Lv-ALR + HR group. ALR overexpression led to suppression of HR-induced apoptosis. Our collective findings indicate that ALR gene transfection alleviates mitochondrial injury, possibly through inhibiting fission and promoting fusion of the mitochondrial inner membrane, both of which contribute to reduction of HK-2 cell apoptosis. Additionally, fission processes are potentially mediated by promoting tubular cell survival through activating the mTOR/4E-BP1 signaling pathway.

Augmenter of Liver Regeneration Alleviates Renal Hypoxia-Reoxygenation Injury by Regulating Mitochondrial Dynamics in Renal Tubular Epithelial Cells

Long, Rui-ting,Peng, Jun-bo,Huang, Li-li,Jiang, Gui-ping,Liao, Yue-juan,Sun, Hang,Hu, Yu-dong,Liao, Xiao-hui Korean Society for Molecular and Cellular Biology 2019 Molecules and cells Vol.42 No.12

Mitochondria are highly dynamic organelles that constantly undergo fission and fusion processes that closely related to their function. Disruption of mitochondrial dynamics has been demonstrated in acute kidney injury (AKI), which could eventually result in cell injury and death. Previously, we reported that augmenter of liver regeneration (ALR) alleviates renal tubular epithelial cell injury. Here, we gained further insights into whether the renoprotective roles of ALR are associated with mitochondrial dynamics. Changes in mitochondrial dynamics were examined in experimental models of renal ischemia-reperfusion (IR). In a model of hypoxia-reoxygenation (HR) injury in vitro, dynamin-related protein 1 (Drp1) and mitochondrial fission process protein 1 (MTFP1), two key proteins of mitochondrial fission, were downregulated in the Lv-ALR + HR group. ALR overexpression additionally had an impact on phosphorylation of Drp1 Ser637 during AKI. The inner membrane fusion protein, Optic Atrophy 1 (OPA1), was significantly increased whereas levels of outer membrane fusion proteins Mitofusin-1 and -2 (Mfn1, Mfn2) were not affected in the Lv-ALR + HR group, compared with the control group. Furthermore, the mTOR/4E-BP1 signaling pathway was highly activated in the Lv-ALR + HR group. ALR overexpression led to suppression of HR-induced apoptosis. Our collective findings indicate that ALR gene transfection alleviates mitochondrial injury, possibly through inhibiting fission and promoting fusion of the mitochondrial inner membrane, both of which contribute to reduction of HK-2 cell apoptosis. Additionally, fission processes are potentially mediated by promoting tubular cell survival through activating the mTOR/4E-BP1 signaling pathway.

Numerical Study on Key Parameters of Magnetorheological Fluid Reciprocating Seal with Four Magnetic Sources

Xiao-long Yang,Fu-xiang Hao,Peng Sun 한국자기학회 2020 Journal of Magnetics Vol.25 No.2

In order to improve the pressure capability of Magnetorheological fluid (MRF) reciprocating seal with four magnetic sources, MRF reciprocating seal structure was designed based on the formula of MRF reciprocating seal. The magnetic field distributons in the sealing gap of MRF reciprocating seals were analyzed by using finite element analysis of magnetic field. The influences of structure parameters such as sealing gap, ratio of permanent magnet height to length, ratio of pole tooth length to width, ratio of slot width to pole tooth width and ratio of pole piece height to the shaft radius on the sealing capabilities were studied. The results were analyzed and discussed. The results show that the pressure capability of MRF seal decreases significantly with the increase of sealing gap. The pressure capability of the MRF seal increases firstly and then decreases with the increase in the ratio of permanent magnet height to its length. The pressure capability of the MRF seal increases firstly and then decreases with the increase in the ratio of pole tooth length to its width. The pressure capability of the MRF seal increases firstly and then decreases with the increase in the ratio of slot width to pole teeth width. The pressure capability of MRF seal decreases with the increase in the ratio of pole piece height to shaft radius.

Study on the Seismic Performance of Bent Columns in Vertical Bent Frame Structures

Xiao-Long Gao,Ling-Yun Peng 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.6

A novel reinforced concrete (RC) vertical bent frame structure system consisting of a RC frame structure and RC bent structure has been proposed for the development of large-scale thermal power plants. To better understand the seismic performance of RC bent columns in vertical bent frame structures, a 1/5-scale representative component selected from a common vertical bent frame structure was tested by quasi-static testing (QST). The failure mode hysteretic characteristics, ductility, energy dissipation capacities of RC bent columns were investigated. Based on the experimental results, finite element models for the bent frame columns and vertical bent frame structures were developed and the nonlinear dynamic analyses were carried out. The results of finite element analysis indicate that the axial pressure ratio has significant effects on the seismic behaviour of RC bent columns. The relationship of drift angle for bent frame column under frequent earthquake and infrequent earthquake are investigated. The limitation values of axial compression ratios and the inter-storey drift angle for RC bent columns in vertical bent frame structures are suggested.

Leaky-Wave Antennas Based on Noncutoff Substrate Integrated Waveguide Supporting Beam Scanning From Backward to Forward

Yue-Long Lyu,Xiao-Xin Liu,Peng-Yuan Wang,Erni, Daniel,Qun Wu,Cong Wang,Nam-Young Kim,Fan-Yi Meng Institute of Electrical and Electronics Engineers 2016 IEEE transactions on antennas and propagation Vol.64 No.6

<P>In this paper, we propose an approach to realize substrate integrated waveguide (SIW)-based leaky-wave antennas (LWAs) supporting continuous beam scanning from backward to forward above the cutoff frequency. First, through phase delay analysis, it was found that SIWs with straight transverse slots support backward and forward radiation of the -1-order mode with an open-stopband (OSB) in between. Subsequently, by introducing additional longitudinal slots as parallel components, the OSB can be suppressed, leading to continuous beam scanning at least from -40 degrees through broadside to 35 degrees. The proposed method only requires a planar structure and obtains less dispersive beam scanning compared with a composite right/left-handed (CRLH) LWA. Both simulations and measurements verify the intended beam scanning operation while verifying the underlying theory.</P>

Characterization on the Beam Profile for Defect Detection of Unidirectional CFRP Composites Using NDE Techniques

Hua Liang,Xiao-Long Shi,Peng Zhang,Gui-Lin Zhang,조영태,염윤택,우용득,임광희 한국생산제조학회 2023 한국생산제조학회지 Vol.32 No.6

Nondestructive evaluation (NDE) technology has garnered interest as an inspection tool in various industries. In this study, ultrasonic technology was applied to the defect monitoring of carbon fiber reinforced plastic (CFRP) composite materials. By using ultrasonic technology, major ultrasonic reflection signals were observed in sequential order for defect evaluation in unidirectional composites. As ultrasonic waves propagate through the unidirectional CFRP composite, mode conversion, attenuation, and scattering results in a relative decrease in the peak-to-peak amplitude of the reflected ultrasonic signals, indicating the presence of defects. In the pitch-catch mode, three to four ultrasonic reflection signals were observed, and by implementing the beam profile of the reflected signals, we confirmed that the signal-to-noise ratio can be utilized as a key parameter for NDE by providing an effective scanning range of ultrasonic amplitudes.

In-pile tritium release behavior and the post-irradiation experiments of Li4SiO4 fabricated by melting process

Zhao Linjie,Yang Mao,Xiao Chengjian,Gong Yu,Ran Guangming,Chen Xiaojun,Li Jiamao,Yue Lei,Chen Chao,Hou Jingwei,Wang Heyi,Long Xinggui,Peng Shuming 한국원자력학회 2024 Nuclear Engineering and Technology Vol.56 No.1

Understanding the tritium release and retention behavior of candidate tritium breeder materials is crucial for breeder blanket design. Recently, a melt spraying process was developed to prepare Li4SiO4 pebbles, which were subsequently subjected to the in-pile tritium production and extraction platform in China Mianyang Research Reactor (CMRR) to investigate their in-situ tritium release behavior and irradiation performance. The results demonstrate that HT is the main tritium release form, and adding hydrogen to the purge gas reduces tritium retention while increasing the HT percent in the purge gas. Post-irradiation experiments reveal that the irradiated pebbles darken in color and their grains swell, but the mechanical properties remain largely unchanged. It is concluded that the tritium residence time of Li4SiO4 made by melt spraying method at 467 ◦C is approximately 23.34 h. High-density Li4SiO4 pebbles exhibit tritium release at relatively low temperatures (<600 ◦C) that is mainly controlled by bulk diffusion. The diffusion coefficient at 525 ◦C and 550 ◦C is 1.19 × 10 11 cm2/s and 5.34 × 10 11 cm2/s, respectively, with corresponding tritium residence times of 21.3 hours and 4.7 hours.

Concurrent Hypermethylation of SFRP2 and DKK2 Activates the Wnt/β-Catenin Pathway and Is Associated with Poor Prognosis in Patients with Gastric Cancer

Hao Wang,Xiang-Long Duan,Xiao-Li Qi,Lei Meng,Yi-Song Xu,Tong Wu,Peng-Gao Dai 한국분자세포생물학회 2017 Molecules and cells Vol.40 No.1

Aberrant hypermethylation of Wnt antagonists has been observed in gastric cancer. A number of studies have focused on the hypermethylation of a single Wnt antagonist and its role in regulating the activation of signaling. However, how the Wnt antagonists interacted to regulate the signaling pathway has not been reported. In the present study, we systematically investigated the methylation of some Wnt antagonist genes (SFRP2, SFRP4, SFRP5, DKK1, DKK2, and APC) and their regulatory role in carcinogenesis. We found that aberrant promoter methylation of SFRP2, SFRP4, DKK1, and DKK2 was significantly increased in gastric cancer. Moreover, concurrent hypermethylation of SFRP2 and DKK2 was observed in gastric cancer and this was significantly associated with increased expression of -catenin, indicating that the joint inactivation of these two genes promoted the activation of the Wnt signaling pathway. Further analysis using a multivariate Cox proportional hazards model showed that DKK2 methylation was an independent prognostic factor for poor overall survival, and the predictive value was markedly enhanced when the combined methylation status of SFRP2 and DKK2 was con-sidered. In addition, the methylation level of SFRP4 and DKK2 was correlated with the patient’s age and tumor differentiation, respectively. In conclusion, epigenetic silencing of Wnt antagonists was associated with gastric carcinogenesis, and concurrent hypermethylation of SFRP2 and DKK2 could be a potential marker for a prognosis of poor overall survival.

Molecular Spinless Energies of the Modified Rosen-Morse Potential Energy Model

Chun-Sheng Jia,Xiao-Long Peng,Su He 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.9

We solve the Klein-Gordon equation with the modified Rosen-Morse potential energy model. The bound state energy equation has been obtained by using the supersymmetric shape invariance approach. The relativistic vibrational transition frequencies for the 61Πu state of the 7Li2 molecule have been computed by using the modified Rosen-Morse potential model. The calculated relativistic vibrational transition frequencies are in good agreement with the experimental RKR values.