Research on non-destructive testing technology for existing bridge pile foundations

Zhang, Xue-feng,Ni, Ying-sheng,Song, Chunxia,Xu, Dong Techno-Press 2020 Structural monitoring and maintenance Vol.7 No.1

Pile foundations of existing bridges lie in soil and water environment for long term and endure relatively heavy vertical loads, thus prone to damages, especially after stricken by external forces, such as earthquake, collision, soil heap load and etc., and the piles may be injured to certain degrees as well. There is a relatively complete technical system for quality inspection of new bridge pile foundations without structures on the top. However, there is no mature technical standard in the engineering community for the non-destructive testing technology specific to the existing bridge pile foundations. The quality of bridge pile foundations has always been a major problem that plagues bridge maintenance. On the basis of many years' experiences in test engineering and theoretical studies, this study developed a new type of detection technology and equipment for the existing bridge piles.

Characterization of Marinilongibacter aquaticus gen. nov., sp. nov., a unique marine bacterium harboring four CRISPR-Cas systems in the phylum Bacteroidota

Zhang Dao-Feng,Yao Yu-Fang,Xue Hua-Peng,Fu Zi-Yue,Zhang Xiao-Mei,Shao Zongze 한국미생물학회 2022 The journal of microbiology Vol.60 No.9

A novel bacterium, designated YYF0007T, was isolated from an agar-degrading co-culture. The strain was found harboring four CRISPR-Cas systems of two classes in the chromosome and subsequently subjected to a study on polyphasic taxonomy. Pairwise analyses of the 16S rRNA gene sequences indicated that strain YYF0007T had highest 16S rRNA gene sequence similarity (92.2%) to Jiulongibacter sediminis JN- 14-9T. The phylogenomic trees based on the 16S rRNA gene and 269 single-copy orthologous gene clusters (OCs) indicated that strain YYF0007T should be recognized as a novel genus of the family Spirosomaceae. The cells were Gramstain- negative, nonmotile, strictly aerobic, and straight long rods with no flagellum. Optimum growth occurred at 28°C and pH 7.0 with the presence of NaCl concentration 1.0–3.0% (w/v). The strain showed oxidase and catalase activities. The major fatty acids were C16:1ω5c, iso-C15:0 and summed feature 3 (C16:1 ω7c and/or C16:1 ω6c). The predominant isoprenoid quinone was MK-7. The complete genome size was 4.64 Mb with a DNA G + C content of 44.4%. Further typing of CRISPR-Cas systems in the family Spirosomaceae and the phylum Bacteroidota indicated that it was remarkable for strain YYF0007T featured by such a set of CRISPR-Cas systems. This trait highlights the applications of strain YYF- 0007T in studies on the evolutionary dynamics and bacterial autoimmunity of CRISPR-Cas system as a potential model. The name Marinilongibacter aquaticus gen. nov., sp. nov. is proposed, and the type strain is YYF0007T (= MCCC 1K06017T = GDMCC 1.2428T = JCM 34683T).

Study on safety early-warning model of bridge underwater pile foundations

Xue-feng Zhang,Chun-xia Song Techno-Press 2023 Structural monitoring and maintenance Vol.10 No.2

The health condition of of deep water high pile foundation is vital to the safe operation of bridges. However, pier foundations are vulnerable to damage in deep water due to exposure to sea torrents and corrosive environments over an extended period. In this paper, combined with aninvestigation and analysis of the typical damage characteristics of main pier group pile foundations, we study the safety monitoring and real-time early warning technology of the deep water high pile foundations, we propose an early warning index item and early warning threshold of deep water high pile foundation by utilizing a numerical simulation analysis and referring to domestic and foreign standards and literature. First, we combine the characteristics of structures and draw on more mature evaluation theories and experience in civil engineering-related fields such as dam and bridge engineering. Then, we establish a scheme consisting of a Early Warning Index Systemand evaluation model based on the analytic hierarchy process and constant weight evaluation method and apply the research results to a project based on the Jiashao bridge in Zhejiang province, China. Finally, we verify the rationality and reliability of the Early Warning Index Systemof the Deep Water High Pile Foundations.

Experimental Investigation of Measurement Error in Networked Resistors Arrays Based on Zero Potential Method

Xue-Feng Zhang,Anjiang Cai,Yulong Zhao 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.4

This paper provides a comprehensive study on the zero potential method for restriction of the crosstalk-based measurement error in network resistor arrays. We introduce four circuits with different architectures based on the zero potential method to comparatively study the effect of the switches on-resistance on the measurement error. Moreover, the effect of the operational amplifiers with different specifications on the measurement error will be investigated. The results show that the measurement error introduced by the onresistance of the switches can be effectively suppressed by inserting a buffer between the sensing elements and the switches on each driven electrode, and utilizing the virtual ground of the trans-impedance amplifier on each scanned electrode. We will show that, the efficiency of the circuits on elimination of the measurement error may be improved by employing high precision operational amplifiers.

Reliable control of magnetic vortex chirality in asymmetrically optimized magnetic nanodisk

Zhang Huanhuan,Yu Hai,Zhang Xue-Feng,Yang Xiao-Xue,Shim Je-Ho,Ma Xiao-Ping,Piao Hong-Guang 한국물리학회 2022 Current Applied Physics Vol.43 No.-

Magnetic vortex has attracted attention in the field of information storage because their topological spin structures with chiral bistable states. If the vortex core polarity and vortex circulation sense can be controlled simultaneously in a nanodisk, which will be more beneficial to realize the multi-bit ultrahigh density storage. In this paper, a reliable control scheme for magnetic vortex chirality is proposed by optimizing the structure of Pac- Man-like nanodisk. The results show that the polarity and circulation of the vortex can be controlled simultaneously by changing the direction of the global magnetic field, and even the chiral states of the vortex can be determined by detecting the stray field distribution on the surface of the nanodisk. The optimized Pac-Man-like nanodisk provide an experimental method for the control and detection of magnetic vortex chirality, which will be beneficial to the realization of multi-bit magnetic storage or magnetic logic technology in the future.

Enhancement of transglutaminase production in Streptomyces mobaraensis DSM 40587 by non-nutritional stress conditions: Effects of heat shock, alcohols, and salt treatments

Lili Zhang,Lanwei Zhang,Huaxi Yi,Ming Du,Yingchun Zhang,Xue Han,Zhen Feng,Jingyan Li,Yuehua Jiao,Yanhe Zhang,Chunfeng Guo 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.7

Stress-mediated bioprocess is a strategy designed to enhance biological target productivity. In this study,an attempt was made to enhance transglutaminase (TGase) production by Streptomyces mobaraensis by using different stress conditions including heat shock, alcohols and salt stress. Results showed that the effects of stress on TGase production depended on the type applied. For heat shock, TGase production (1.32 U/ml) was recorded maximum in the culture treated at 48 h post inoculation in water bath at 60 oC for 1 min. For alcohols treatment, the maximum activity of TGase (1.77 and 1.75 U/ml) was obtained when 3% methanol was added into the medium at 0 or 24 h of fermentation. However, a 3.5-fold increased production of TGase (3.8 U/ml) was observed in the medium supplemented with 0.2mol/l MgCl2 compared with the basic medium at the beginning of fermentation. In conclusion, TGase production from S. mobaraensis was improved by heat shock, methanol and salt stress treatments, MgCl2 stress was the most effective.

Lentivirus-mediated silencing of the PTC1 and PTC2 genes promotes recovery from spinal cord injury by activating the Hedgehog signaling pathway in a rat model

Ya-Dong Zhang,Zhong-Sheng Zhu,Dong Zhang,Zhen Zhang,Bin Ma,Shi-Chang Zhao,Feng Xue 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

This study aimed to investigate the effect of Patched-1 (PTC1) and PTC2 silencing in a rat model, on Hedgehog (Hh) pathwaymediated recovery from spinal cord injury (SCI). An analytical emphasis on the relationship between the sonic hedgehog (Shh) pathway and nerve regeneration was explored. A total of 126 rats were divided into normal, sham, SCI, negative control (NC), PTC1-RNAi, PTC2-RNAi and PTC1/PTC2-RNAi groups. The Basso, Beattie and Bresnahan (BBB) scale was employed to assess hind limb motor function. Quantitative real-time polymerase chain reaction and western blotting were performed to examine the mRNA and protein levels of PTC1, PTC2, Shh, glioma-associated oncogene homolog 1 (Gli-1), Smo and Nestin. Tissue morphology was analyzed using immunohistochemistry, and immunofluorescent staining was conducted to detect neurofilament protein 200 (NF-200) and glial fibrillary acidic protein (GFAP). The PTC1/PTC2-RNAi group displayed higher BBB scores than the SCI and NC groups. Shh, Gli-1, Smo and Nestin expression levels were elevated in the PTC1/PTC2-RNAi group. PTC1 and PTC2 mRNA and protein expression was lower in the PTC1/PTC2-RNAi group than in the normal, sham and SCI groups. Among the seven groups, the PTC1/PTC2-RNAi group had the largest positive area of NF-200 staining, whereas the SCI group exhibited a larger GFAP-positive area than both the normal and the sham groups. The Shh pathway may provide new insights into therapeutic indications and regenerative recovery tools for the treatment of SCI. Activation of the Hh signaling pathway by silencing PTC1 and PTC2 may reduce inflammation and may ultimately promote SCI recovery.

Effects of iodine doping on structural and electrical characteristics of solution-processed indium oxide thin-film transistors and its potential application for iodine sensing

Feng Junhao,Choi Ji-Hoon,Zhang Xue,Park Jaehoon,Bae Jin-Hyuk 한국물리학회 2024 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.85 No.1

This study investigated the infuence of solution-processed indium oxide (In2O3) thin-flm transistors (TFTs) with various iodine vapor (I2) doping times. Prolonged iodine doping time is found to induce some important changes in the devices: (i) increase in In2O3 flm thickness and nanoparticle size; (ii) decrease in the metal-hydroxyl bonding and increase in the metal– oxygen bonding; (iii) the positive moved threshold voltage, lower feld-efect mobility, and higher on/of current ratio from 0 s (sec) to 10 s. Furthermore, vacuum thermal treatment, as a facial, novel method to recover the electrical performances of I2-doped In2O3 TFTs was examined. I2-doped In2O3 TFTs for 10 s with vacuum thermal treatment at 200 ℃ exhibited excellent recovery properties of electrical. The results indicate that iodine doping can change the electrical properties of In2O3 TFTs and could potentially be used for I2 gas sensor.

Simulation of oxygen mass transfer in fuel assemblies under flowing lead-bismuth eutectic

Feng, Wenpei,Zhang, Xue,Chen, Hongli Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.5

Corrosion of structural materials presents a critical challenge in the use of lead-bismuth eutectic (LBE) as a nuclear coolant in an accelerator-driven system. By forming a protective layer on the steel surfaces, corrosion of steels in LBE cooled reactors can be mitigated. The amount of oxygen concentration required to create a continuous and stable oxide layer on steel surfaces is related to the oxidation process. So far, there is no oxidation experiment in fuel assemblies (FA), let alone specific oxidation detail information. This information can be, however, obtained by numerical simulation. In the present study, a new coupling method is developed to implement a coupling between the oxygen mass transfer model and the commercial computational fluid dynamics (CFD) software ANSYS-CFX. The coupling approach is verified. Using the coupling tool, we study the oxidation process of the FA and investigate the effects of different inlet parameters, such as temperature, flow rate on the mass transfer process.

Demography and mass-rearing of Carposina sasakii Matsumura (Lepidoptera: Carposinidae) reared on Golden Delicious and Red Fuji apples in the laboratory

Feng Dandan,Xue Qiqi,Men Lina,Li Xiaofei,Deng Angie,Zhang Yuhong,Ma Ruiyan,Zhang Zhiwei 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.4

Carposina sasakii Matsumura (Lepidoptera: Carposinidae), is one of the most serious fruit-boring pests in over ten species of fruit trees, and is especially damaging apples in the northern of China. The application of new planting systems, i.e., high-density and dwarfing rootstock orchard systems with mixed apple varieties, makes it im portant to study the fitness of C. sasakii on these apple varieties to gain fundamental knowledge for use in pest management involving this insect. In this study, life table data of C. sasakii were collected using Golden Delicious and Red Fuji apples as hosts. The egg-larva duration of male C. sasakii reared on Golden Delicious apples (22.81 d) was significantly shorter than that reared on Red Fuji apples (24.27 d). The egg-larva mortality in Golden Delicious apples (59.00%) was lower than that in Red Fuji apples (72.49%). The mortality of the pupal stage, however, was higher in Golden Delicious (10.51%) than in Red Fuji (0%). The total oviposition period (TPOP) on Golden Delicious apples (32.94 d) was significantly shorter than in individuals reared on Red Fuji apples (34.19 d). The intrinsic rate of increase (r = 0.0581 d −1 ), net reproductive rate (R 0 = 7.57 offspring), and finite rate of increase (λ = 1.0598 d −1 ) were all higher on Golden Delicious than those on Red Fuji. When the net re productive rate (R 0 ) was used, the harvest rate of pupae was higher (0.8678) when reared on Golden Delicious apples than when reared on Red Fuji apples (0.8398). When a large cohort size (n = 200) was used for effective bootstrap sample, the P E values for C. sasakii reared on Golden Delicious apples and Red Fuji apples were both almost equal to 1. For C. sasakii culturing purposes, Golden Delicious apples would be more productive than Red Fuji.