437 results on '"Han, Xiaohui"'
Search Results
202. A New Series of Nanoporous Ionic Crystals Based on Polyoxometalates – Synthesis, Crystal Structures, and Adsorption Properties
- Author
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Han, Xiaohui, primary, Xu, Lin, additional, Li, Fengyan, additional, and Jiang, Ning, additional
- Published
- 2011
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203. Dynamically Modeling Semantic Dependencies in Web Forum Threads
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Ren, Zhaochun, primary, Ma, Jun, additional, Wang, Gang, additional, Cui, Chaoran, additional, and Han, Xiaohui, additional
- Published
- 2011
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204. Disrupted in schizophrenia 1 (DISC1) regulates ATM‐mediated NFκB activation during hypoxia and reoxygenation (H/R)
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Liu, Jia‐Ren, primary, Ibla, Juan Carlos, additional, Liu, Qian, additional, Li, Jing, additional, Han, Xiaohui, additional, and Khoury, Joseph, additional
- Published
- 2010
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205. Notice of Retraction: Based on the energy consumption of the smallest three-phase asynchronous motor Optimize Control of Energy Saving
- Author
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Liu, Jianye, primary, Shi, Song, additional, Han, Xiaohui, additional, and Liu, Jia, additional
- Published
- 2010
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206. Hierarchical Document Classification Based on a Backtracking Algorithm
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Zhu, Cuiling, primary, Ma, Jun, additional, Zhang, Dongmei, additional, Han, XiaoHui, additional, and Niu, Xiaofei, additional
- Published
- 2008
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207. Autoantibodies Closely Relate to the Elevation Level of In Vivo Hydrogen Peroxide and Tissue Damage in Systemic Lupus Erythematosus
- Author
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Wang, Yongquan, primary, Qiao, Bin, additional, Wang, Ying, additional, Han, Xiaohui, additional, Chu, Yiwei, additional, and Xiong, Sidong, additional
- Published
- 2006
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208. Dynamically Modeling Semantic Dependencies in Web Forum Threads.
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Ren, Zhaochun, Ma, Jun, Wang, Gang, Cui, Chaoran, and Han, Xiaohui
- Published
- 2011
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- View/download PDF
209. Based on the energy consumption of the smallest three-phase asynchronous motor Optimize Control of Energy Saving.
- Author
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Liu Jianye, Shi Song, Han Xiaohui, and Liu Jia
- Published
- 2010
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210. Energy efficiency evaluation method of rural low-voltage distribution network based on combination weight method.
- Author
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Han Xiaohui, Du Songhuai, Su Juan, Tian Heping, and Qu Bo
- Abstract
Aimed at understanding the overall energy efficiency level of rural low-voltage distribution network, and on the basis of analyzing current research on energy saving indexes of distribution network, the energy efficiency evaluation index system and evaluation model of rural low-voltage distribution network were established in this article. Firstly, according to relevant standards and rules, a set of comprehensive index system for evaluating energy efficiency of rural low-voltage distribution network was established. The index system consisted of seven second grade indexes, such as the electric network structure, network equipment, power quality, network loss, economic operation of power network, reactive power compensation and distributed generation. Particularly, electric network structure index included 4 third grade indexes: the proportion of distribution transformer located at the load center and 380V line power radius beyond the standard, the percentage of small section for 380 V line and connecting line; the network equipment index contained 3 third grade indexes: the ratio of efficient type distribution transformer, non-standardized distribution transformer capacity and energy-efficient low-voltage line; the power quality index consisted of 4 third grade indexes: the qualified rate of 380 V three-phase load unbalance degree, 380/220 V voltage monitoring point, 380V voltage and current total harmonic distortion; the network loss index included 4 third grade indexes: the comprehensive loss rate of distribution transformer and low voltage, the number of serious exceed the standard rate of loss rate for single distribution transformer and low voltage; the economic operation of power network index consisted of one third grade index that distribution transformer load rate of interval number in the economic; the reactive power compensation index included 4 third grade indexes: reactive power compensation device installation and operation rate, distribution transformer monthly average power factor qualification rate, reactive power compensation capacity accounted for distribution transformer capacity ratio; the distributed generation index include the capacity and generating capacity ratio of distributed generation accessed to the low voltage district; all together 22 third grade indexes. Then, the calculation method for 22 third grade indexes was determined, the 22 single efficiency indexes were obtained and the comprehensive evaluation model which was proposed based on principal component analysis and analytic hierarchy process was used to calculate energy efficiency of rural low-voltage distribution network. The concrete methods were: according to the principal component analysis, the index matrix for each second grade indexes was determined, and by means of 0-9 scaling method of analytic hierarchy process, the comprehensive weight of the second grade index was determined, thus the method overcame the shortcomings of single weighting method and realized the combination of the quantitative result from energy efficiency index and the qualitative result from the judge of relevant experts ,which made the evaluation results more reasonably. Finally, Taking low-voltage distribution network of three districts in rural as example, the evaluation result of three districts obtained by the method proposed in the paper were completely in conformity with the result of actual distribution network efficiency, which indicated that the proposed method in this paper was the effective and practicable. It provides a reference for implementing electric-saving reconstruction and energy-saving assessment of rural low-voltage distribution network in China. [ABSTRACT FROM AUTHOR]
- Published
- 2014
211. Teacher Cognition of Intercultural Communicative Competence in the Chinese ELT Context.
- Author
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Han Xiaohui and Song Li
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CROSS-cultural communication ,ENGLISH teachers ,ENGLISH as a foreign language ,HIGHER education - Abstract
This pilot study is an inquiry into teacher cognition of intercultural communicative competence (ICC) in the Chinese English language teaching (ELT) context of higher education in which teacher cognition is fundamental to any pedagogical practice or reform. Through a questionnaire survey among university English teachers, the authors wish to find out the status quo of teacher cognition on various aspects of ICC-oriented ELT, in particular how these English teachers conceptualize ICC, how they perceive ICC in relation to ELT, how they believe ICC can be best fostered through ELT, how their perception is related and realized in their own teaching practice, and how they relate ICC teaching to the development of learners' other competencies in English, etc. The results suggest that the Chinese university English teachers' conceptualization of ICC and its relevance to ELT is vague in spite of their perceived goal and strong desire to develop students' ICC. Such results indicate the significance of intercultural teacher education and the interculturalization of ELT in the Chinese context. [ABSTRACT FROM AUTHOR]
- Published
- 2011
212. An Empirical Study on the Effects of Comprehensible Input on Incidental English Vocabulary Recognition.
- Author
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Han Xiaohui
- Subjects
EMPIRICAL research ,VOCABULARY ,LEXICON ,SECOND language acquisition ,BILINGUAL education - Abstract
This study investigates the effects of comprehensible input on incidental English vocabulary recognition. Immediately after receiving different types of input, 220 non-English major freshmen took a posttest of vocabulary recognition. The results of the current study validate the positive effects of premodified input, interactionally modified input and modified output on English learners' incidental vocabulary recognition. Enhanced input and modified output play significantly facilitated roles in the short-term memory of English learners and further result in better instant lexical recognition. [ABSTRACT FROM AUTHOR]
- Published
- 2010
213. Differences in leaf phenological traits between trees and shrubs are closely related to functional traits in a temperate forest.
- Author
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Wang, Lei, Han, Xiaohui, Yin, Qiulong, Wang, Guoxiang, Xu, Jinshi, Chai, Yongfu, and Yue, Ming
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TEMPERATE forests , *COEXISTENCE of species , *LEAF morphology , *DECIDUOUS forests , *TREES , *SHRUBS , *WOODY plants - Abstract
Leaf phenological traits vary greatly with plant species, are thought to relate to leaf functional traits, and play an important role in plant growth. In this study, we investigated leaf phenological and functional traits of 52 woody species (324 individuals) from a natural forest in the Loess Plateau in China. Shrubs obtain a longer leaf life span (LLS) through early leaf emergence and later leaf senescence. Shrubs have a longer LLS compared with trees because they have a greater leaf thickness than trees (to prevent early spring frost), leaf phosphorus content ([P] leaf , related to cell division), and C:N ratio and stem density (to prevent mechanical damage). Among all woody species, species with a small SLA and leaf area and species with thick leaves have a longer leaf emergence duration and LLS, which may be related to material energy reserves. In addition, shrubs had a greater [P] leaf and C:N ratio and a longer leaf emergence duration. Our results reveal differences in leaf phenological traits among life forms and indicate that plant functional traits can provide insight into the mechanisms underlying such differences. In addition, the results of this study provide insight into species coexistence and community assembly in temperate deciduous forests. • Leaf phenology traits varied between trees and shrubs in a temperate forest. • Shrubs generally leafed out earlier and shed later than trees. • Leaf morphology traits contributed to explain differences in phenology traits. • Leaf phenology traits were closely related to the stoichiometry traits. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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214. Microstructure, Mechanical Properties and Corrosion Behavior of the Aluminum Alloy Components Repaired by Cold Spray with Al-Based Powders.
- Author
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Zhang, Zhiyi, Sun, Xiaoguang, Huang, Shiming, Han, Xiaohui, Zhu, Ping, Shi, Chunyuan, and Zhang, Tengfei
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SPARE parts ,SALT spray testing ,MICROSTRUCTURE ,ALUMINUM alloys ,PROBLEM solving ,POWDERS ,ALLOY powders - Abstract
Aluminum alloy components of high-speed trains have a great risk of being corroded by various corrosive medium due to extremely complex atmospheric environments. This will bring out huge losses and reduce the safety and stability of trains. In order to solve the problem, cold spray process was used for repairing the damage of the aluminum alloy components with Al-based powders. Microstructure, mechanical properties and corrosion behavior were studied. The results indicated that there were very few pores and cracks in the repaired areas after repairing. The average microhardness of the repaired areas was 54.5 HV ± 3.4 HV, and the tensile strength of the repaired samples was 160.4 MPa. After neutral salt spray tests for 1000 h, the rate of mass loss of the samples repaired by cold spray was lower than that of 6A01 aluminum alloy. The electrochemical test results showed that the repaired areas had a higher open circuit potential than 6A01 aluminum alloy. As a result, the repaired areas such as the anode protected its nearby substrate. The samples repaired by cold spray exhibited better corrosion than 6A01 aluminum alloy. Cold spray process and Al-based powders are applicable for repairing the aluminum alloy components of high-speed trains. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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215. Immediately loaded fixed full-arch implant-retained prosthesis: a solution to the extreme defect in zone 2—a case report.
- Author
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Lu, Xiaoya, Wang, Xiaoping, Han, Xiaohui, Hu, Lihua, Ji, Mei, Li, Shengfeng, and Huang, Shengyun
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DENTURES , *MAXILLARY sinus , *COMPACT bone , *PROSTHETICS , *MAXILLA , *EXTRUSION process , *DENTAL implants , *DEEP brain stimulation - Abstract
Background: Implants immediately loaded full-arch prosthesis in maxilla is always a challenge, especially when the zone 2 is extremely defected. To achieve a satisfying result, different therapeutic alternatives have been proposed, such as zygomatic implant, pterygoid implant; however, precise surgical skills limited its application. Case presentation: This study reported a case that an edentulous patient was treated with a new technique, two axial implants and four tilted implants supporting an immediate fixed denture, extruding the cortical bone of the anterior wall of the maxillary sinus to establish the primary stability. Conclusions: Two-year follow-up proves that it is a viable choice. Meanwhile, a reliable method for its saving time and money and low level of discomfort for patients is presented. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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216. Appropriate supply of sulfur alleviates lead toxicity and stimulates its accumulation in hyperaccumulator Arabis alpina.
- Author
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Wang, Lei, Gao, Yuxuan, Han, Xiaohui, Li, Zuran, Mou, Fengli, Bi, Jiayu, Zu, Yanqun, and Wang, Jixiu
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PLANT biomass , *LEAD , *SOIL remediation , *GENE expression , *HEAVY metals , *GAS exchange in plants - Abstract
Widespread lead (Pb) contamination of agricultural soils is a global issue stemming from human activities. The remediation of Pb-contaminated soils used for agricultural purposes is critically important to safeguard food crop safety. Despite the modulating effects of sulfur (S) on plant responses to toxic heavy metals, the ecological, physiological, and molecular mechanisms driving such modulation in the Pb hyperaccumulator Arabis alpina L. remain unclear. Here, we investigated the effects of five S concentrations (0, 50, 100, 150, and 200 mg kg−1) on A. alpina grown in Pb-contaminated soil from a lead-zinc mining area. Under S50 (i.e., 50 mg kg−1) and S100 treatments, the Pb concentration in both shoots and roots of A. alpina significantly decreased compared to the control (S0). Specifically, the S50 treatment significantly enhanced Pb accumulation, plant biomass, and plant height, indicating that low S applications facilitate Pb accumulation from the soil and alleviate Pb toxicity. Additionally, S50, S100, and S150 treatments significantly improved photosynthetic rate, stomatal conductance, and intercellular CO 2 concentration in A. alpina. Transcriptomic analysis showed that S50 and S100 treatments increased the expression of the LHCA, LHCB , psa , and psb genes, which had a significant impact on photosynthetic efficiency. S50 and S100 boosted glutathione (GSH) levels in A. alpina roots, and the increased expression of GST gene enhanced tolerance to environmental stress. In summary, these results suggest that an appropriate supply of S (S50 and S100) not only alleviates Pb toxicity by enhancing plant biomass, height, photosynthetic features, and sulfur metabolites but also stimulates Pb accumulation in the hyperaccumulator A. alpina. Our study elucidated the specific concentrations of sulfur that optimally enhance both Pb accumulation and stress tolerance in the hyperaccumulator A. alpina , providing novel insights into the practical application of sulfur in phytoremediation strategies and advancing our understanding of the underlying molecular mechanisms. [Display omitted] • Sulfur supply enhanced plant growth and lead accumulation simultaneously. • S supply increased photosynthetic efficiency and expression of related genes. • S supply boosted GSH level, enhanced GST expression, improved plant tolerance. [ABSTRACT FROM AUTHOR]
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- 2024
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217. Improving image-based weld defects detection under interference information via a novel semantic supervision strategy.
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Yang, Biao, Wang, Wei, Chen, Guoqing, Liu, Fuyun, Han, Xiaohui, Chen, Bo, Song, Xiaoguo, and Tan, Caiwang
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WELDING defects , *INSPECTION & review , *INFORMATION resources management , *ALGORITHMS , *PIXELS - Abstract
Weld defects of skin-skeleton structures are invisible and image-based visual inspections using deep learning neural networks are in demand. The main limitation of previous detection algorithms is interference information in images. The reflective light and uneven brightness distribution hinder algorithms to achieve higher detection reliability. In this work, a novel supervision strategy for defects detection algorithms was proposed to break the limitation. A new semantic gate convolution block was developed to help the neural networks to distinguish between targets and interference. The block utilised semantic segmentation labels and a gate function to control the information transmitted to the detection output. Additionally, a new category-pixel-accuracy loss function was adopted to improve the effectiveness of semantic features. The new function reduced the effects of negative pixels to avoid over emphasis on semantic completeness, thus the ineffective features of interference could be eliminated. The results indicated that the back-propagated gradients from the supervision part taught the backbone networks to focus on correct objects instead of interference. To testify the validity of the current method, the algorithms was verified in burns and collapse defects. The detection accuracy under the new semantic supervision reached 99.1%, which was superior to common CNN. [ABSTRACT FROM AUTHOR]
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- 2024
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218. A Comparison of Polyvalent Passive Immunoprotection from Antibodies with Different Immunity Models of Live or Inactivated Vibrio fluvialis in Fish.
- Author
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Xiao, Huihui, Cui, Pan, Chen, Jing, Han, Xiaohui, Ma, Ziye, Chen, Chen, Liu, Yong, and Liu, Xiang
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VIBRIO , *AEROMONAS hydrophila , *IMMUNITY , *IMMUNE serums , *GOLDFISH , *FISH pathogens , *IMMUNOSENESCENCE - Abstract
Polyvalent passive vaccines can act fast in resisting various bacteria with good efficacy, and they have application value in aquaculture. This study prepared live and inactivated Vibrio fluvialis mouse antisera (L-VF-antiserum and I-VF-antiserum), and administered them to goldfish (Carassius auratus) infected with V. fluvialis and Aeromonas hydrophila. The passive protective rates of live and inactivated mouse antisera against V. fluvialis were 60% (p < 0.05) and 40% (p < 0.05), and their passive cross-protective rates against A. hydrophila were 42.86% (p < 0.05) and 35.71% (p < 0.05), respectively. Furthermore, the two mouse antisera could recognize the bacteria in vitro; the content of bacteria in the C. auratus kidney decreased (p < 0.05), the phagocytic activity of C. auratus leukocytes was enhanced (p < 0.05), and the expression of inflammatory genes and activity of antioxidant factors decreased (p < 0.05). Moreover, the kidney, spleen, and intestinal tissue structures were intact, and the apoptosis and DNA damage were decreased (p < 0.05) among the kidney cells. The live V. fluvialis antiserum contained more antibodies against the outer membrane proteins of V. fluvialis than the inactivated mouse antiserum. The immunoprotective abilities of the live V. fluvialis antiserum were higher than those of the inactivated antiserum, and the antiserum of live V. fluvialis immunity demonstrated potential application value as a polyvalent passive immune vaccine in fish. [ABSTRACT FROM AUTHOR]
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- 2024
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219. Exogenous transforming growth factor-β1 prevents the inflow of fluoride to ameleoblasts through regulation of voltage-gated chloride channels 5 and 7.
- Author
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Ji, Mei, Duan, Xuejing, Han, Xiaohui, Sun, Jing, and Zhang, Dongsheng
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CHLORIDE channels ,FLUORIDES ,FLUOROSIS ,FLUORESCENT probes ,ENDOPLASMIC reticulum - Abstract
Dental fluorosis is a global issue. Although there are multiple causes of dental fluorosis, the precise mechanism remains controversial. Previous studies have demonstrated that extracellular fluoride may promote an accumulation of fluoride ions in ameloblasts, which may induce oxidative and endoplasmic reticulum stresses, leading to dental fluorosis. However, the exact process by which fluoride ions enter cells has not been determined. In the present study, intracellular fluoride concentration was determined using a newly developed specific fluorescent probe called probe 1. Under high extracellular fluoride concentrations, the fluorescence intensity of the ameloblasts increased, however, exogenous transforming growth factor-β1 (TGF-β1) was able to inhibit the increase. Furthermore, changes in the expression of the voltage-gated chloride channels 5 and 7 (ClC5 and ClC-7), which are responsible for the transport of fluoride were investigated. The results indicated that fluoride reduced the expression of endogenous TGF-β1 and increased the expression of ClC-5 and ClC-7. Additionally, exogenous TGF-β1 reduced the expression of ClC-5 and ClC-7. The results of the present study indicate that exogenous TGF-β1 may prevent accumulation of fluoride in ameloblasts through the regulation of ClC-5 and ClC-7 under high extracellular fluoride concentrations. [ABSTRACT FROM AUTHOR]
- Published
- 2021
220. Porosity distribution and mechanical response of laser-MIG hybrid butt welded 6082-T6 aluminum alloy joint.
- Author
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Han, Xiaohui, Yang, Zhibin, Ma, Yin, Shi, Chunyuan, and Xin, Zhibin
- Subjects
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ALUMINUM alloy welding , *BUTT welding , *POROSITY , *ELECTRIC welding , *DUCTILE fractures - Abstract
• Effects of porosity distributions on the tensile and fatigue properties were studied. • Porosities appeared near the fusion line in the arc zone with high arc current. • Low welding speed or arc current was benefit for reducing the porosity rate. • Fracture locations of the tensile specimens were mainly related with the porosity rate. • Fracture diverted from ductile to ductile and brittle mixed mode as porosity increased. 6082-T6 aluminum alloy with thickness of 6 mm were welded by laser-MIG hybrid welding. The effects of welding parameters on the porosity distribution, the correlations between the porosity distribution and mechanical properties were comprehensively investigated. The porosities mainly appeared near the fusion line of the arc zone when the arc current larger than 140 A, and which mainly existed in the center of the laser zone with other unsuitable parameters. Adopting low welding speed and setting heat source distance as around 3 mm were beneficial for the reduction of the porosity rate. The laser power, defocus distance, fit-up gap and gas flow rate had less effects on the porosity distribution. The average tensile strength of the joints without porosities was 260 MPa, which decreased to 224 MPa and 202 MPa as the porosity rate increased to 5.1% and 8.9%. The tensile specimens fractured at the heat affected zone or in the weld center when the porosity rates less or greater than 3%, and the fracture feature was diverted from ductile fracture to ductile and brittle mixed mode as the porosity rate increasing. The fatigue strength reduced from 113 MPa to 56 MPa when the porosity rate increased from 0% to 8.9%, while the porosity position had little effect on it. The fracture initiated in the weld surface when the joints without porosity, and which initiated near the porosity when the porosities existed in the joint. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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221. Correction to: Effect of 650-nm low-level laser irradiation on c-Jun, c-Fos, ICAM-1, and CCL2 expression in experimental periodontitis.
- Author
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Zhang, Lin, Chen, Wenlei, Li, Yingxin, Hong, Wei, Li, Haidong, Cui, Zhuang, Dong, Xiaoxi, Han, Xiaohui, Bao, Gang, Xiao, Li, Gao, Pengfei, and Wang, Yonglan
- Subjects
LASER beams ,PERIODONTITIS ,CD54 antigen - Abstract
After publication of our article [1] we realized that we had not acknowledged that some of the text overlaps with a previous publication [2]. We apologize to readers for this error. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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222. A VMD-BP Model to Predict Laser Welding Keyhole-Induced Pore Defect in Al Butt–Lap Joint.
- Author
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Wang, Wei, Dong, Yang, Liu, Fuyun, Yang, Biao, Han, Xiaohui, Wei, Lianfeng, Song, Xiaoguo, and Tan, Caiwang
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LASER welding , *WELDING defects , *FEATURE extraction , *SIGNAL processing , *PREDICTION models , *PLASMA arc welding , *BUTT welding - Abstract
The detection of keyhole-induced pore positions is a critical procedure for assessing laser welding quality. Considering the detection error due to pore migration and noise interference, this research proposes a regional prediction model based on the time–frequency-domain features of the laser plume. The original plume signal was separated into several signal segments to construct the morphological sequences. To suppress the mode mixing caused by environmental noise, variational modal decomposition (VMD) was utilized to process the signals. The time–frequency features extracted from the decomposed signals were acquired as the input of a backpropagation (BP) neural network to predict the pore locations. To reduce the prediction error caused by pore migration, the effect of the length of the signal segments on the prediction accuracy was investigated. The results show that the optimal signal segment length was 0.4 mm, with an accuracy of 97.77%. The 0.2 mm signal segments failed to eliminate the negative effects of pore migration. The signal segments over 0.4 mm resulted in prediction errors of small and dense pores. This work provides more guidance for optimizing the feature extraction of welding signals to improve the accuracy of welding defect identification. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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223. Influence of process parameters on the joint characteristics during laser joining of aluminium alloy and CFRTP
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Feng, Ziwei, Ma, Guolong, Su, Jianhui, Tan, Caiwang, Han, Xiaohui, Zhao, Hongyun, Chen, Bo, and Song, Xiaoguo
- Abstract
Fiber laser joining of 6061 aluminium alloy and carbon fiber reinforced thermoplastic composite (CFRTP) was performed in this work. The effect of three process parameters including laser power, traveling speed and defocus distance on the bonding interface and joint properties was investigated. Shear tests were performed to evaluate the joint strength in different variables. X-ray photoelectron spectroscopy (XPS) was adopted to confirm the chemical states of elements at the interface. The results indicated that the shear strength of joints first increased and then decreased with the increase of heat input. Insufficient flow of CFRTP could not fill the grooves of aluminium alloy surface at low heat input. The resin was decomposed at excessisvely high heat input, causing pores remained at the interface. The fracture mode was determined as the interface failure. XPS result revealed that no new chemical bond was found at the interface, and the mechanical interlocking between aluminium alloy and CFRTP was main bonding mechanism. The maximum shear strength was 23.8 MPa, which was obtained as laser power, traveling speed and defocus distance was 1100 W, 5 mm/s and +10 mm, respectively.
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- 2021
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224. Coral-based rare earth element proxy for hydrothermal fluid on the Yongxing Island, South China Sea.
- Author
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Wei, Haotian, Liu, Gang, Han, Xiaohui, Zhao, Yanyan, Wu, Jiaqing, Yang, Jun, Li, Sanzhong, Zhang, Yang, and Li, Dongyong
- Subjects
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CORAL reefs & islands , *RARE earth metals , *CORALS , *ISLANDS , *FLUIDS , *BONE growth - Abstract
Explanation: A systematic research on chronology, mineral compositions, geochemistry, particularly the rare earth elements of the SSZK1 well suggests that the YX-2300 coral bone formed at 114 ka have obvious positive Eu anomalies (A), and the model calculations suggest that at least 0.1% of hydrothermal fluids were added to the surrounding seawater during its growth (B and C). [Display omitted] • The environment of most coral samples in this study can be well judged as the marine environment with oxidation conditions. • The similarity in the distribution patterns of REE+Y in P1 and P2 suggests that diagenetic alteration has little influence. • Obvious positive Eu anomalies and the REE + Y distribution model indicate the involvement of hydrothermal fluids. Coral reefs play an important role in the high-resolution paleoclimate and paleoenvironment records. In particular, the contents, distribution patterns and elemental anomalies of the rare earth elements can reflect the paleoceanic conditions and sedimentary environments. In this study, we focus on the SSZK1 core in the Coral Reef of Yongxing Island, South China Sea (SCS). The sediments of this core can be divided into two stages: P1 (18.00–24.95 m) and P2 (24.95–55.92 m), based on the dating results. The results show that the coral reefs of P1 and P2 stages have slightly different REE contents, but similar REE + Y patterns. In general, the REE + Y patterns of both P1 and P2 stages are similar to those of normal marine carbonates (rocks), showing LREE depletion, negative Ce anomaly and high Y/Ho ratios. This indicates that the REEs of coral preserved their pristine geochemical features although they have experienced the diagenetic alteration to some degree. However, the samples, such as the YX-2300 coral bone formed at 114 ka, have obvious positive Eu anomalies except the similar REE + Y characteristics as the normal marine carbonates (rocks). The positive Eu anomalies indicate that some hydrothermal fluids may be input into the surrounding water at the time of coral bone formation. Based on the model calculations, at least 0.1% of hydrothermal fluids were added to the surrounding seawater during the growth of YX-2300 coral bone. By comparing the data and ages, it is suggested that these hydrothermal fluids could be associated with volcanic activities on Gaojishi Island or Hainan Island. This evidence is important to trace the occurrence of modern worldwide volcanism or deep faults activity in the deep-sea. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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225. Enhancing the properties of metal-composite interface by a nano-TiO2 coating.
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Feng, Ziwei, Zhang, Xueyan, Li, Haoyue, Su, Jianhui, Tan, Caiwang, Han, Xiaohui, Zhao, Hongyun, Chen, Bo, and Song, Xiaoguo
- Subjects
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TITANIUM dioxide , *FIBROUS composites , *INTERFACIAL bonding , *JOINING processes , *CARBON composites , *ALUMINUM composites , *FAILURE mode & effects analysis , *THERMOPLASTIC composites , *CARBON fibers - Abstract
The application of metal-polymer structures has been restricted by challenges in achieving effective bonding between the two materials. To address this, nano-TiO 2 coatings were introduced to improve the interfacial bonding between the treated 6061 Al alloy and carbon fiber-reinforced thermoplastic composite (CFRTP) during the laser joining process. The results highlighted that the joints created with nano-TiO 2 coatings achieved significantly higher tensile shear force and strength, reaching 1.43 and 1.37 times the values of those without particles, respectively. This improvement can be attributed to the following factors: firstly, the incorporation of coatings led to an increase in the absorption of hydroxy groups, thereby improving the wettability of the Al alloy, which in turn promoted the formation of hydrogen bonds at the interface. Secondly, the increased surface roughness favored the chemical interaction between the Al alloy and CFRTP, ascribed to the enlarged contact area. Moreover, this change influenced the thermal contact conductance (TCC), thereby changing the temperature at the interface and joining areas of the two materials. Finally, a notable transformation in the failure mode was observed, transitioning from adhesive failure to cohesive failure when compared to joints without nano-TiO 2 coatings. This underscored the reinforcing role played by nano-TiO 2 particles, providing an innovative solution for enhancing the interface bonding between dissimilar materials. [ABSTRACT FROM AUTHOR]
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- 2024
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226. The relationships between biomass allocation and plant functional trait.
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Yin, Qiulong, Tian, Tingting, Han, Xiaohui, Xu, Jinshi, Chai, Yongfu, Mo, Jiao, Lei, Maolin, Wang, Lei, and Yue, Ming
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MULTIPLE correspondence analysis (Statistics) , *LEAF area , *BIOMASS , *INVERSE relationships (Mathematics) - Abstract
Graphical abstract Highlights • Leaf mass fraction (LMF) is mainly related to draught tolerance. • Leaf area ratio (LAR) is mainly related to light capture. • LMF and LAR play different roles in the acclimation of plants. Abstract Understanding how plants allocate biomass to different organs is of high importance since biomass allocation among organs determines many growth processes. Biomass allocation among plant organs is driven by environmental conditions, while functional traits can also be potential covariates to understand the allocation of biomass. However, the relationships between functional traits and biomass allocation remain poorly known and studied. We investigated the relationships of two biomass allocation indicators, including leaf mass fraction (LMF) and leaf area ratio (LAR), with six economic traits and five hydraulic traits across 30 woody species. We found that LMF and LAR showed different relationships with economics traits. In addition, a significantly negative correlation was observed between LMF and leaf water potential at turgor loss point (TLP), but no significant relationship was found between LAR and TLP. Principal component analyses showed that LMF-related traits and LAR-related traits could be divided into two groups. Taken together, LMF is mainly related to draught tolerance while LAR mainly related to light capture. Although LMF and LAR are two significantly correlated biomass allocation indicators, they play different roles in the acclimation of plants. Researchers should focus on the different functions of these two indicators and the different relationships with other functional traits in the further research. [ABSTRACT FROM AUTHOR]
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- 2019
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227. ChemInform Abstract: Synthesis, Crystal Structure, and Optical Property of a One-Dimensional Selenidostannate: [AEPPH2]2[Sn5Se12] (AEPP = N-Aminoethylpiperazine).
- Author
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Han, Xiaohui, Meng, Junling, Xu, Jin, Liu, Xiaojuan, Liu, Dan, and Wang, Cheng
- Subjects
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TIN compounds synthesis , *SELENIUM , *COPPER chlorides , *CRYSTAL structure , *X-ray diffraction , *CRYSTALLIZATION - Abstract
The title compound is solvothermally synthesized from a solution of Sn, Se, and CuCl in a 1:1 mixture of N-aminoethylpiperazine and EtOH (autoclave, 200 °C, 6 d, 38% yield). [ABSTRACT FROM AUTHOR]
- Published
- 2016
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228. Study on Corrosion Resistance of Stainless-Steel Welded Joints with SnSb8Cu4 and SnZn9.
- Author
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Wang, Jintao, Wang, Shengxi, Wang, Bo, Han, Xiaohui, Liu, Yong, Ye, Jiehe, and Cheng, Zhan
- Subjects
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RESISTANCE welding , *CORROSION resistance , *SOLDER & soldering , *STAINLESS steel , *BRAZING - Abstract
The use of soldering based on metallurgical bonding, as opposed to conventional rubber sealing, is capable of achieving the firm sealing of stainless-steel subway car bodies, though the corrosion resistance of such joints has rarely been investigated. In this study, two typical solders were selected and applied to the soldering of stainless steel, and their properties were investigated. As indicated by the experimental results, the two types of solder exhibited favorable wetting and spreading properties on stainless-steel plates, and successfully achieved sealing connections between the stainless-steel sheets. In comparison with the Sn-Zn9 solder, the Sn-Sb8-Cu4 solder exhibited lower solidus–liquidus, such that it can be more suitably applied to low-temperature sealing brazing. The sealing strength of the two solders reached over 35 MPa, notably higher than that of the sealant currently used (the sealing strength is lower than 10 MPa). In comparison with the Sn-Sb8-Cu4 solder, the Sn-Zn9 solder exhibited a higher corrosion tendency and a higher degree of corrosion during the corrosion process. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
229. Study on the microstructure and properties of spray formed 7055-T76 aluminum alloy joints by rotating magnetic field assisted friction stir welding.
- Author
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Chen, Xinyi, Chen, Shujin, Duan, Ruihai, Gao, Yang, Liu, Zhihong, Dong, Jihong, and Han, Xiaohui
- Subjects
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FRICTION stir welding , *ALUMINUM forming , *ALUMINUM alloys , *BUTT welding , *MAGNETIC fields - Abstract
This study explores an electrically-magnetically-assisted friction stir welding (EMAFSW) method, conducting butt welding experiments on T76 tempered spray-formed 7055 aluminum alloy. Compared to traditional friction stir welding (FSW) processes, the EMAFSW method maintained basically consistent weld hardness, while tensile strength and elongation increased by 13.1% and 72.3%, respectively. The rotating magnetic field enhanced the mechanical stirring action of the welding tool, reduced the size of precipitates, promoted dislocation pinning, and increased the mobility of dislocations. The stirred zone (SZ) and thermo-mechanically affected zone (TMAZ) of EMAFSW weld joint showed significant grain refinement and increased recrystallization proportion, enhancing the weld joint toughness. The joint's fracture behavior shifted from brittle to ductile fracture. • A new method based on rotating magnetic field assisted FSW is proposed. • The grains in SZ and TMAZ of 4 mm-thick spray-formed 7055-T76 aluminum alloy are obviously refined. • The strength of the welded joint is stable and the toughness is improved under the assistance of the magnetic field. • The rotating magnetic field enhances the dislocation motion and improves the plastic flow of the metal during FSW. • EMAFSW is expected to expand the process window of friction stir welding. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
230. Single-sided friction riveting process of aluminum sheet to profile structure without prefabricated hole.
- Author
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Yang, Bingxin, Shan, He, Han, Xiaohui, Lin, Sen, Ma, Yunwu, Lou, Ming, Wang, Xiaojie, and Li, Yongbing
- Subjects
- *
ALUMINUM sheets , *RIVETED joints , *FRICTION , *RIVETS & riveting , *ALUMINUM construction , *PEAK load - Abstract
Aluminum profile structures are extensively used in the transportation industry and pose a considerable challenge to single-sided spot joining technologies. The widely used Huck BOM® riveting process requires prefabricated holes and thus significantly increases cost and reduces efficiency. In this study, a novel single-sided friction riveting (SSFR) process with an internal-threaded semi-tubular rivet is proposed to realize a screwed-solid state hybrid joining of aluminum sheet to profile structure without prefabricated holes. The results show that the upper trapped metal is welded with the lower profile structure under the thermal-mechanical coupled action generated by rivet stirring. The internal thread could facilitate material filling into the rivet cavity and form a mechanical interlock, so as to realize the single-sided joining between the sheet and the profile without prefabricated holes. The one-stage SSFR process could form shear texture and promote continuous dynamic recrystallization, but lead to excessive material softening and internal cracking. A two-stage process including friction softening and screw tightening could better coordinate the effects of heat and force, thereby avoiding cracking and refining grains in the stirring zone. Finally, the tensile-shear and cross-tension peak loads were respectively improved by 9.0 % and 29.3 %, compared to the joints with one-stage process and non-structural rivet. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
231. Seismic Imaging and 3D Architecture of Yongle Atoll of the Xisha Archipelago, South China Sea.
- Author
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WU, Shiguo, ZHANG, Hanyu, QIN, Yongpeng, CHEN, Wanli, LIU, Gang, and HAN, Xiaohui
- Subjects
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IMAGING systems in seismology , *THREE-dimensional imaging , *CORAL reefs & islands , *ARCHIPELAGOES , *VOLCANIC ash, tuff, etc. , *MIOCENE Epoch - Abstract
Yongle atoll in the Xisha (Paracel) Archipelago is an isolated carbonate platform developed on Precambrian metamorphic and Mesozoic volcanic rocks since the early Miocene. To identify the 3D stratigraphic architecture and evolution of this platform, 13 high‐resolution seismic profiles and shallow‐to‐deep water multi‐beam data were processed and analyzed to reveal seismic facies, sequence boundary reflectors, seismic units, and platform architecture. Nine types of seismic facies were recognized based on their geometry, which included seismic amplitude, continuity, and termination patterns; additionally, six reflections, i.e., Tg, T60, T50, T40, T30, and T20, were identified in the Cenozoic strata. Five seismic units, SQ1 (lower Miocene), SQ2 (middle Miocene), SQ3 (upper Miocene), SQ4 (Pliocene), and SQ5 (Quaternary), were identified from bottom to top across the platform. The platform grew rapidly in the middle Miocene and backstepped in the late Miocene–Pliocene. Here, we discuss the developmental characteristics and evolution of the Yongle Atoll, in combination with drilling wells, which can be divided into four stages: the initiation stage in the early Miocene, the flourishing stage in the middle Miocene, the partial‐drowning stage in the late Miocene–Pliocene, and modern atoll in the Quaternary. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
232. LncRNA Airn maintains LSEC differentiation to alleviate liver fibrosis via the KLF2-eNOS-sGC pathway.
- Author
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Chen, Ting, Shi, Zhemin, Zhao, Yanmian, Meng, Xiaoxiang, Zhao, Sicong, Zheng, Lina, Han, Xiaohui, Hu, Zhimei, Yao, Qingbin, Lin, Huajiang, Du, Xiaoxiao, Zhang, Kun, Han, Tao, and Hong, Wei
- Abstract
Background: Long noncoding RNAs (lncRNAs) have emerged as important regulators in a variety of human diseases. The dysregulation of liver sinusoidal endothelial cell (LSEC) phenotype is a critical early event in the fibrotic process. However, the biological function of lncRNAs in LSEC still remains unclear.Methods: The expression level of lncRNA Airn was evaluated in both human fibrotic livers and serums, as well as mouse fibrotic livers. Gain- and loss-of-function experiments were performed to detect the effect of Airn on LSEC differentiation and hepatic stellate cell (HSC) activation in liver fibrosis. Furthermore, RIP, RNA pull-down-immunoblotting, and ChIP experiments were performed to explore the underlying mechanisms of Airn.Results: We have identified Airn was significantly upregulated in liver tissues and LSEC of carbon tetrachloride (CCl4)-induced liver fibrosis mouse model. Moreover, the expression of AIRN in fibrotic human liver tissues and serums was remarkably increased compared with healthy controls. In vivo studies showed that Airn deficiency aggravated CCl4- and bile duct ligation (BDL)-induced liver fibrosis, while Airn over-expression by AAV8 alleviated CCl4-induced liver fibrosis. Furthermore, we revealed that Airn maintained LSEC differentiation in vivo and in vitro. Additionally, Airn inhibited HSC activation indirectly by regulating LSEC differentiation and promoted hepatocyte (HC) proliferation by increasing paracrine secretion of Wnt2a and HGF from LSEC. Mechanistically, Airn interacted with EZH2 to maintain LSEC differentiation through KLF2-eNOS-sGC pathway, thereby maintaining HSC quiescence and promoting HC proliferation.Conclusions: Our work identified that Airn is beneficial to liver fibrosis by maintaining LSEC differentiation and might be a serum biomarker for liver fibrogenesis. [ABSTRACT FROM AUTHOR]- Published
- 2022
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233. Association of X-linked TLR-7 gene polymorphism with the risk of knee osteoarthritis: a case–control study.
- Author
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Xi, Xutao, Mehmood, Arshad, Niu, Pengyan, Yang, Jinjie, Wang, Yintian, Zhou, Heyu, Han, Xiaohui, Ma, Lifen, Jin, Shiying, and Wu, Yinxia
- Subjects
- *
KNEE , *GENETIC polymorphisms , *KNEE osteoarthritis , *CHINESE people , *CASE-control method , *TOLL-like receptors - Abstract
Knee osteoarthritis (OA) is the most prevalent type of OA, and Toll-like receptor 7 (TLR7) may lead to the pathogenesis of OA. Recently, X-linked TLR7 polymorphism has been confirmed to be associated with arthritis. However, there is a lack of studies on TLR7 gene polymorphism associated with knee OA susceptibility. The current study aimed to determine whether TLR7 gene polymorphism is associated with the risk of knee OA. Genotyping of two polymorphic sites (rs3853839 and rs179010) in the TLR7 gene was performed in 252 OA patients, and 265 healthy controls using the SNaPshot sequencing technique. Data were analyzed statistically by Chi-square tests and logistic regression. Rs3853839-C allele showed frequencies of 28% and 27% in the healthy control and female knee OA groups, respectively. The differences were not statistically significant (P > 0.05). The rs3853839-CG genotype frequency was significantly lower in the female knee OA group as compared to the healthy control group (OR 0.60; 95%CI 0.36–0.99; P = 0.044). In the male hemizygote population, the rs3853839-CC showed significantly lower frequencies in the male knee OA group as compared to the healthy control group (OR 0.35; 95%CI 0.17–0.71; P = 0.0025). Regarding rs179010, there were no differences in the genotype distribution and allele frequencies between OA patients and healthy subjects under any models (P > 0.05). Stratified analysis showed that the frequency of the rs3853839-CG genotypes was lower in high Kellgren-Lawrence grades (KLG) (OR 0.48; 95%CI 0.21–1.08; P = 0.066), and significantly lower in OA patients with effusion synovitis (OR 0.38; 95%CI 0.17–0.88; P = 0.013). TLR7 rs3853839 polymorphism may play a role in the susceptibility of knee OA in the Chinese Han Population and may be associated with OA severity and the risk of effusion synovitis in Knee OA. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
234. Dexmedetomidine directly binds to and inhibits Toll-like receptor 4.
- Author
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Koutsogiannaki, Sophia, Limratana, Panop, Bu, Weiming, Maisat, Wiriya, McKinstry-Wu, Andrew, Han, Xiaohui, Ohto, Umeharu, Eckenhoff, Roderic G., Soriano, Sulpicio G., and Yuki, Koichi
- Subjects
- *
TOLL-like receptors , *BINDING sites , *MEDETOMIDINE , *MICROGLIA , *INVECTIVE , *DEXMEDETOMIDINE - Abstract
• Dexmedetomidine attenuated TLR4 activation signal. • Dexmedetomidine directly bound TLR4 for its inhibition. • Dexmedetomidine attenuated microglia activation. While a number of anesthetics has been shown potentially associated with neurotoxicity in the developing brain, dexmedetomidine, a drug that was rather recently introduced into the perioperative setting, is considered beneficial from neurological wellbeing. However, the underlying mechanism of how dexmedetomidine affects brain health remains to be determined. Based on our recent study, we hypothesized that dexmedetomidine would directly bind to and inhibit Toll-like receptor 4 (TLR4), a critical receptor largely expressed in microglia and responsible for neurological insult. We used TLR4 reporter assays to test if dexmedetomidine attenuates TLR4 activation. Furthermore, a direct binding of dexmedetomidine on TLR4 was tested using photoactivatable medetomidine. Lastly, the effect of dexmedetomidine on ketamine (anesthetic)-induced neurotoxicity was tested in rat pups (P7). We showed that dexmedetomidine attenuated TLR4 activation using reporter assay (IC 50 = 5.8 µg/mL). Photoactivatable dexmedetomidine delineated its direct binding sites on TLR4. We also showed that dexmedetomidine attenuated microglia activation both in vitro and in vivo. We proposed a novel mechanism of dexmedetomidine-mediated neuroprotection. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
235. Achievement of high-strength Al/CFRP hybrid joint via high-speed friction stir lap joining and laser texturing pretreatment parameters variation.
- Author
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Liu, Yuchun, Wang, Xinbo, Zhou, Li, Zhao, Hongyun, Han, Xiaohui, Tan, Caiwang, and Song, Xiaoguo
- Subjects
- *
LASERS , *FRICTION , *JOINING processes , *SURFACE texture , *COMPRESSION loads , *SHEAR strength - Abstract
• Achievement of high strength Al/CFRP hybrid joint via laser texturing pretreatment. • High friction stir joining speed which reached 3000 mm/min. • Establishing evaluation criteria of laser-textured joint: anchorage value. • Analysis including the semi-crystalline property of PA66 and temperature simulation. This paper presents the achievement of a high-strength Al/CFRP hybrid joint through a high-speed friction stir lap joining process, combined with variations in laser surface texturing pretreatment parameters. The study examined the impact of laser surface texturing parameters by varying the depth, interval distance and width of the laser texture. By adjusting laser texturing parameters, the softened PA66 was fully infused into the textured grooves on the aluminum surface, leading to a significant reduction in interfacial voids and cracks in Al/CFRP. The preliminary tensile shear test showed that the hybrid joint broke at the CFRP base material, indicating that the laser texturing exhibited excellent Al/CFRP interface strengthening ability. Further compression shear tests were applied to reveal the actual interfacial load-carrying performance for comparison. The maximum shear strength of 25. 5 − 1.34 + 0.7 MPa was achieved at a joining speed of 3000 mm/min. Additionally, a mathematical model was proposed to assess the strengthening impact of laser texturing parameters, considering micro-texture geometry and interfacial defects. The tearing of PA66, detachment of carbon fibers, and the breakage of carbon fibers were the three primary types of fracture modes identified at the Al/CFRP interface. The joining mechanism revealed that both mechanical interlocking and the chemical bonding of Al-O-C contributed to the increase in joint shear strength. This study presents a credible method for producing high-strength Al/CFRP lightweight structures. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
236. Cylindrical metalens for multidimensional control of terahertz waves.
- Author
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Zhao, Huan, Liu, Siyuan, Chen, Zhuo, Sang, Yungang, Han, Xiaohui, Xue, Linhu, Wang, Yu, Wang, Xinke, Zhang, Yan, and Han, Chunrui
- Subjects
- *
SUBMILLIMETER waves , *UNIT cell , *FOCAL planes , *NUMERICAL apertures , *LINEAR polarization , *CIRCULAR polarization , *BEAM steering - Abstract
• By tailoring the arrangement of the unit cells in a 2D array, the incident circular polarization can split into two orthogonal linear polarizations and focus on different positions of the focal plane. • The amplitude of the focal lines can be tailored in a gradient distribution by tuning the rotation angle of the C-shaped antenna. • The focusing efficiency of the cylindrical metalens reaches up to 64.7% with a numerical aperture (NA) of 0.75 for high efficient one-dimensional collection of the terahertz waves. • A standard UV lithography with lift off is used for the fabrication which is compatible with the mass production in a chip factory. Metalens, consisting of planar micro/nanostructure arrays, has shown great potentials in beam steering, subwavelength focusing and high-resolution imaging. Taking the advantages of ultrathin thickness and compact design, it can be integrated with a photonic chip to improve the collection efficiency of optoelectronic systems. However, it remains challenging to realize the multidimensional control of terahertz (THz) waves by using a metalens, although the convergence properties have been widely studied. Here, we design and experimentally demonstrate a multifunctional cylindrical metalens by using a tri-layer metallic metasurface. By modulating the amplitude, phase and polarization states of terahertz waves independently, the cylindrical metalens can generate two focal lines at different positions for transmitted x - and y - polarized terahertz waves with varying amplitude distribution. Importantly, up to 64.7% focusing efficiency has been obtained at the frequency of 0.34 THz with a numerical aperture (NA) of 0.75. Our study offers a novel method for implementing multifunctional cylindrical metalens which lays the foundation of advanced integration with arrayed terahertz detection chips. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
237. Comparative Transcriptomics Analysis of Roots and Leaves under Cd Stress in Calotropis gigantea L.
- Author
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Yang, Jingya, Li, Lingxiong, Zhang, Xiong, Wu, Shibo, Han, Xiaohui, Li, Xiong, and Xu, Jianchu
- Subjects
- *
CALOTROPIS , *FOLIAR diagnosis , *HEAVY metal toxicology , *SOIL remediation , *COMPARATIVE studies , *GERMINATION - Abstract
Calotropis gigantea is often found in mining areas with heavy metal pollution. However, little is known about the physiological and molecular response mechanism of C. gigantea to Cd stress. In the present study, Cd tolerance characteristic of C. gigantea and the potential mechanisms were explored. Seed germination test results showed that C. gigantea had a certain Cd tolerance capacity. Biochemical and transcriptomic analysis indicated that the roots and leaves of C. gigantea had different responses to early Cd stress. A total of 176 and 1618 DEGs were identified in the roots and leaves of C. gigantea treated with Cd compared to the control samples, respectively. Results indicated that oxidative stress was mainly initiated in the roots of C. gigantea, whereas the leaves activated several Cd detoxification processes to cope with Cd, including the upregulation of genes involved in Cd transport (i.e., absorption, efflux, or compartmentalization), cell wall remodeling, antioxidant system, and chelation. This study provides preliminary information to understand how C. gigantea respond to Cd stress, which is useful for evaluating the potential of C. gigantea in the remediation of Cd-contaminated soils. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
238. Evaluation of myopic corneal diameter with the Orbscan II Topography System.
- Author
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Zha, Yi, Feng, Wangqiang, Han, Xiaohui, and Cai, Jianqiu
- Subjects
- *
CORNEAL topography , *MYOPIA treatment , *VISUAL accommodation , *MIRROR images , *ANTERIOR eye segment , *RETROSPECTIVE studies - Abstract
Background: To assess the myopic corneal diameter with Orbscan II Topography System (Bausch & Lomb, Orbtek Inc., Salt Lake City, UT, USA). Methods: Four hundred sixty-two eyes of 231 myopic patients and 129 emmetropic eyes were measured with the Orbscan II system. Eyes were divided into four groups according to the spherical equivalent(SE) as follows: group 1 [emmetropic group, spherical equivalents between −0.50 D and +0.50 D (−0.50
- Published
- 2013
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239. Synergistic inhibition of cerium and alkyl phosphate composite adlayer on pitting corrosion of Al–Mg–Si aluminium alloy.
- Author
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Sun, Xiaoguang, Cao, Xiangkang, Zhang, Zhiyi, Han, Xiaohui, Ruan, Hongmei, and Dong, Zehua
- Subjects
- *
PITTING corrosion , *ALUMINUM alloys , *CERIUM oxides , *CERIUM , *CORROSION resistance , *NOISE measurement - Abstract
The nucleation, propagation, and rehabilitation of pitting corrosion of Al–Mg–Si Aluminium alloy (AA6063) are studied in 3%NaCl solution by using electrochemical noise measurement. It shows that the composite film composed of sequent precipitation of ceria and 1-tetradecylphosphonic acid (DPA) presents the best pitting corrosion resistance compared with the independent ceria conversion film or self-assembling DPA film. XPS and microscopic Raman spectra confirmed that Ceria film is an excellent interlayer for the self-assembling of alkyl phosphate on the intermetallic particles in Al alloy. The anti-corrosion performance of Cerium oxides and DPA composite film is totally dependent on the deposition sequence. Prior deposition of ceria and then DPA film can increase the hydrophilicity of Al matrix and AlFeSi intermetallic particles, further promoting the self-assembling of upper DPA molecules, thus dramatically improving the overall and pitting corrosion resistance of AA6063. This could be attributed to the synergistic effects between the upper DPA film and underlying Ce conversion film. On the contrary, Prior assembly of DPA and then deposition of ceria, may significantly degrade their inhibition efficiency. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
240. Improving the adhesion of cold sprayed Al deposits through in-situ micro-forging.
- Author
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Luo, Xiao-Tao, Liu, Xingke, Wei, Yingkang, Han, Xiaohui, and Li, Chang-Jiu
- Subjects
- *
SHOT peening , *METAL coating , *MATERIAL plasticity , *ELASTIC modulus , *STAINLESS steel , *METAL spraying , *POWDERS - Abstract
The much lower processing temperature makes cold spray have many merits to deposit metallic coatings, repair failed metallic parts and additively manufacture metallic parts as compared with the high-energy beam based metal depositing processes. Although adhesion is critical for coating and repairing applications for cold sprayed deposits, it is still challenging to get high bonding strength especially for depositing materials with low density and elastic modulus. Here we introduced an in-situ micro-forging (MF) effect to cold spray by mixing 200–300 µm big-sized 410 stainless steel shot peening particles into the depositing Al powder. Due to the in-situ forging by the shot peening particles with 100 time higher kinetic energy than the depositing Al particle, vortex-like material intermixing between the Al deposit and the AZ31BMg substrate is periodically formed along the deposit/substrate interface. Meanwhile, the greatly improved interfacial plastic deformation at the deposit/substrate interface remarkably promotes the breaking and segmentation of the native oxide scale on both the spraying particle surface and substrate surface which promotes metallurgical bonding formation across the deposit/substrate interface. Both the vortex-like material intermixing induced enhanced mechanical interlocking and the improved metallurgical bonding contribute to a higher adhesion. As a consequence, the adhesion of Al deposit increases from 47.9 MPa to 107.2 MPa. [Display omitted] • An in-situ micro-forging is introduced into cold spray to improve the adhesion. • Vortex-like material intermixing is periodically formed along the interface. • More dispersed interfacial oxide scale leads to improved metallurgical bonding fraction. • Adhesion of cold sprayed Al deposit is improved from 47.9 MPa to 107.2 MPa. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
241. Effect of 650-nm low-level laser irradiation on c-Jun, c-Fos, ICAM-1, and CCL2 expression in experimental periodontitis.
- Author
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Zhang, Lin, Chen, Wenlei, Li, Yingxin, Hong, Wei, Li, Haidong, Cui, Zhuang, Dong, Xiaoxi, Han, Xiaohui, Bao, Gang, Xiao, Li, Gao, Pengfei, and Wang, Yonglan
- Subjects
- *
PERIODONTITIS , *CD54 antigen , *ANTI-inflammatory agents , *GENE expression , *OSTEOCLASTS , *RNA metabolism , *PROTEIN metabolism , *PROTEINS , *MACROPHAGES , *RNA , *RATS , *GENES , *RESEARCH funding , *INFLAMMATORY mediators , *ANTIGENS , *GINGIVA , *ANIMALS - Abstract
This study was designed to investigate the effect of 650-nm low-level laser irradiation (LLLI) as an adjunctive treatment of experimental periodontitis. To investigate possible LLLI-mediated anti-inflammatory effects, we utilized an experimental periodontitis (EP) rat model and analyzed c-Jun, c-Fos, ICAM-1, and CCL2 gene expressions on PB leukocytes and in the gingival tissue. Total RNA was isolated from the gingivae and peripheral blood (PB) leukocytes of normal, EP, scaling, and root planing (SRP)-treated EP and LLLI + SRP-treated EP rats, and gene expressions were analyzed by real-time PCR. The productions of c-Jun, c-Fos, ICAM-1, and CCL2 in gingivae were analyzed immunohistochemically. Tartrate-resistant acid phosphatase (TRAP) staining was used to determine osteoclast activity in alveolar bone. The c-Jun and ICAM-1 messenger RNA (mRNA) levels were significantly decreased in the EP rat gingival tissue treated by SRP + LLLI than by SRP, the c-Jun, ICAM-1, and c-Fos mRNA levels on PB leukocytes reduced after LLLI treatment but did not show any significant differences in both groups. There was no significant difference in CCL2 mRNA levels on PB leukocytes and in gingivae between the SRP + LLLI and the SRP groups. The c-Fos mRNA levels in gingivae did not show significant difference in both groups. Immunohistochemistry showed that the CCL2, ICAM-1, c-Jun, and c-Fos productions were significantly reduced in rats of the SRP + LLLI group compared with the only SRP group. LLLI significantly decreased the number of osteoclasts as demonstrated by TRAP staining. The 650-nm LLLI might be a useful treatment modality for periodontitis. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
242. Submarine landslides on a carbonate platform slope changing transport pathways of deepwater gravity flows: Insights from the Xisha Islands, South China Sea.
- Author
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Liu, Gang, Wang, Dawei, Chen, Wanli, Wang, Weiwei, Betzler, Christian, and Han, Xiaohui
- Subjects
- *
LANDSLIDES , *SLOPES (Physical geography) , *SUBMARINE valleys , *OCEAN engineering , *TURBIDITY currents , *GRAVITY - Abstract
Landslides frequently block rivers, forming a barrier lake, resulting in a dam break event in the terrestrial environment. However, reports about the submarine landslides are scarce. Herein, the periplatform submarine landslides changing transport pathways of deepwater gravity flows within the southeastern region out of Xuande Atoll on the Xisha Islands, South China Sea, are described. Submarine landslides, including SL I and SL II, with a total area of 170.9 km2, were identified using up-to-date geophysical data, including multi-beam bathymetric and seismic data and sediment gravity cores. SL I directly connects the Sansha Canyon forming a large-scale negative relief with an area of 151.8 km2, developing the terraces, and transporting blocks and remnant blocks. SL II covers an area of 19.1 km2 and was mainly deposited on the deepwater plain with a toe part that is higher than the initial seafloor. The negative relief created by SL I on the seafloor forms the dominant pathways for the gravity flows, creating the new active channel system directly flowing into the canyon. The turbidity currents flowing along the steep lateral margin of SL II formed the cyclic steps. The remnant submarine landslide deposits on the western canyon margin indicate that SL I previously blocked the canyon and formed a submarine barrier lake, which was then eroded by the gravity flows flowing along with the channel system within SL I and the upstream canyon. Finally, the canyon was formed again, whose axis was "pushed" eastward by SL I. These observations update the evolution model of submarine landslide on a carbonate platform slope and the transport system from the slope to the submarine canyon or the deep basin and clarify the stability of submarine engineering and island-and-reef systems. • Our results help understand the initiation and emplacement processes of submarine landslides around the atoll. • Submarine landslides are the major conduits for shallow-water sediment transport into deep-water environments. • Submarine canyonning process can evacuate the distal part of a submarine landslide on the carbonate platform slope. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
243. The mechanism study of TIG-MIG hybrid welding process based on simulation.
- Author
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Cui, Xuefei, Chen, Ji, Xia, Chunyang, Han, Xiaohui, Su, Hao, and Wu, Chuansong
- Subjects
- *
GAS metal arc welding , *CCD cameras , *WELDING , *ELECTRIC welding , *METAL vapors , *LIQUID metals - Abstract
Tungsten inert gas-metal inert gas (TIG-MIG) hybrid welding combines the advantages of tungsten inert gas (TIG) welding and metal inert gas (MIG) welding. Due to the benefits of the two welding techniques, it is an effective strategy to enhance welding quality and productivity. To investigate the mechanism of arcs interaction in TIG-MIG hybrid welding, a three-dimensional transient model for arc-droplet-weld pool behavior was established. The temperature field, metal vapor content, flow fluid, current density and electromagnetic force in the arc space and weld pool were simulated and analyzed. The calculation results showed that the introduction of the TIG arc decreased the content of metal vapor and increased the arc temperature. Compared with single MIG welding, the amplitudes of maximum arc temperature and plasma velocity in TIG-MIG hybrid welding were lower. Experimental results demonstrated that the droplet deflection angle, droplet transfer frequency, weld bead cross-section, and arc temperature distribution all agreed well with calculated values. • The distribution of current density near tungsten tip was derived based on CCD camera. • The influence of the metal vapor on the arc and molten metal behavior were evaluated. • The maximum electromagnetic force near the MIG droplet was almost three times of TIG-MIG. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
244. Enhanced the bonding reliability of titanium alloy and CFRTP via interfacial multiple modification: Synergy of physical interlocking and chemical interaction.
- Author
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Su, Jianhui, Tan, Caiwang, Wang, Xinbo, Li, Haoyue, Liu, Yifan, Han, Xiaohui, Feng, Ziwei, Xia, Hongbo, Chen, Bo, and Song, Xiaoguo
- Subjects
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TITANIUM alloys , *SILANE coupling agents , *CHEMICAL structure , *CHEMICAL bonds , *METAL bonding - Abstract
• A novel approach for enhancing bonding reliability of metal and CFRTP was proposed. • Synergetic mechanism of interfacial physical–chemical dual scales was elucidated. • The multiple modification approach enhanced the bonding reliability by 166%. • Oxide structures were confirmed as the condition of interfacial chemical bonding. • Hydrogen bonds were successfully induced and captured at the bonding interface. A novel multiple modification approach including laser texturing, micro-arc oxidation process and silane coupling agent treatment was proposed to optimize the bonding interface. Firstly, laser texturing was fabricated to promote the mechanical interlocking. Secondly, the micro-arc oxidation porous structure was designed to modify its physical structure and chemical states. This promoted the interfacial mechanical interlocking in dual scales including texturing and porous structures. Moreover, the new chemical bonds such as Ti-C and Ti-O were generated at the interface. The bonding strength of TC4/CFRTP was enhanced from 10.23 MPa to 23.41 MPa. Besides, more hydroxyl groups (–OH) were adsorbed inside the optimized structure, and the hydrogen bonds were successfully induced by silane coupling film via the final step. This further enhanced the bonding strength to the maximum of 27.22 MPa. Therefore, the multiple modification approach realized the comprehensive enhancement of mechanical interlocking, chemical bonding and functional groups interaction, which enhanced the bonding reliability by 166% than pretreated case. These results benefit future research in the process optimization to improve the reliability of metal-CFRTP bonding structures. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
245. Film-forming mechanism of 1,3-propanediolcyclic sulfate as a bifunctional additive for 4.45 V graphite/LiCoO2 batteries.
- Author
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Wang, Siwu, Guo, Huajun, Li, Xinhai, Wang, Zhixing, Wang, Jiexi, Han, Xiaohui, Zhang, Changming, and Yan, Guochun
- Subjects
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INTERFACIAL reactions , *X-ray photoelectron spectroscopy , *NEGATIVE electrode , *ENERGY density , *DENSITY functional theory , *GRAPHITE - Abstract
Increasing the cutoff voltage is efficient to increase the energy density of LiCoO 2 -based lithium-ion batteries to meet consumers' demand for electronic devices. However, higher cut-off voltage may lead to continuous decomposition of electrolyte and shorten the battery's cycle life. Herein, 1,3-propanediolcyclic sulfate (PCS) is designed as a film-forming additive to improve the electrochemical performance of high-voltage graphite/LiCoO 2 cells. The combined density functional theory (DFT) calculations and experimental results indicate that PCS participates in the film formation on both LiCoO 2 cathode and graphite anode side to regulate the interfacial reaction and inhibit the corresponding gas production. Thus, the capacity retention of 4.45 V graphite/LiCoO 2 pouch cells cycled at 45 °C after 300 cycles is elevated from 59.5% to 80.1% by incorporating 1.0 wt% PCS additive into the base electrolyte. It is found that PCS follows the C-O bond breaking mechanism on the positive electrode and S-O bond breaking mechanism on the negative electrode, respectively. In addition, PCS may undergo H-transfer reaction at the cathode in the first cycle because the -O-SO 2 - group appears as oxidation product in ex-situ X-ray photoelectron spectroscopy (XPS) results. This finding provides new insights for understanding the mechanism of PCS acting as a high-voltage additive. • PCS can participate in film formation on both electrodes. • PCS follows the C-O bond breaking mechanism to produce -O-SO 3 - species on LiCoO 2. • -O-SO 2 - is produced by PCS following the S-O bond breaking mechanism on graphite. • PCS can improve the high voltage performance of graphite/LiCoO 2 cells. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
246. Tensile and fatigue behaviors of hybrid laser welded A7N01 alloy with repairing for railway vehicles.
- Author
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Wu, Zhengkai, Zhou, Xiru, Ao, Ni, Han, Xiaohui, Zhu, Zongtao, and Wu, Shengchuan
- Subjects
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LASER welding , *WELDED joints , *RAILROAD trains , *WELDING defects , *ALLOYS , *HIGH speed trains - Abstract
• Hybrid laser heat source was selected for repairing of hybrid laser welded A7N01 alloy. • Defects in original joints were effectively eliminated by hybrid laser heat source. • HCF property with a little increase can be obtained compared with original joints. As one of the key concerns in the health maintenance system for modern railway equipment, defect repair plays an important role in enhancing the running safety reliability and economic benefits. In this study, welding defects of A7N01 alloy commonly used in high-speed trains were repaired by hybrid laser welding. The surface integrity of the welded zone before and after repairing was evaluated by various characterization methods in terms of the microstructures, tensile and fatigue properties. The results show that the original incomplete penetration defects would be eliminated by welding repair, giving rise to some microstructural changes such as the grain refinement and the widening of fine grain zone in the original welded joints. The heat input during welding repairing induced significantly reduction of the hardness and tensile strength from 105 HV to 75 HV and from 358 MPa to 338 MPa, respectively. Nevertheless, the fatigue properties of hybrid welded A7N01 alloy with the hybrid welding repairing were improved by 33.8%, probably because of reduced defects. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
247. Hydrothermal synthesis of Y3NbO7 nanowires for the photocatalytic degradation of omeprazole sodium.
- Author
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Zhao, Jie, He, Qiang, Yao, Binghua, Zhang, Qian, Zhang, Ting, Wang, Qianqian, and Han, Xiaohui
- Subjects
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HYDROTHERMAL synthesis , *YTTRIUM compounds , *NANOWIRES , *PHOTOREDUCTION , *OMEPRAZOLE , *SODIUM compounds - Abstract
Novel Y 3 NbO 7 nanowires were successfully synthesized by a facile hydrothermal method using Y(NO 3 ) 3 ·6H 2 O and Nb 2 O 5 as raw materials. X-ray power diffraction (XRD), High resolution transmission electron microscopy (HR-TEM), UV–vis diffuse reflectance spectroscopy (UV–vis-DRS), X-ray photoelectron spectroscopy (XPS) and Brunauer–Emmett–Teller (BET) techniques were employed to determine the structure, morphology, specific surface area and optical properties of the as-prepared samples. Photocatalytic examination of the samples was carried out using aqueous solution of omeprazole sodium under visible light irradiation. The effects of initial omeprazole sodium concentration and catalyst amount on the photocatalytic degradation were also investigated. Detailed characterization demonstrated that Y 3 NbO 7 nanowires have cubic fluorite crystal structure with a diameter of about 20 nm and a length up to several micrometers. Photocatalytic activity tests revealed that omeprazole sodium photocatalytic reactions followed pseudo-first-order kinetics and Y 3 NbO 7 nanowires exhibited greater photocatalytic activity than its bulk counterparts. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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248. Therapeutic efficacy of three bispecific antibodies on collagen-induced arthritis mouse model.
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Li, Qingcui, Ren, Guiping, Xu, Liming, Wang, Qiuying, Qi, Jianying, Wang, Wenfei, Zhou, Bing, Han, Xiaohui, Sun, Cuiyu, Wu, Qiang, Yu, Yinhang, Peng, Zhongyi, Zheng, Shimin, and Li, Deshan
- Subjects
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BISPECIFIC antibodies , *TREATMENT effectiveness , *COLLAGEN diseases , *TREATMENT of arthritis , *LABORATORY mice , *INTERLEUKINS - Abstract
Abstract: Interleukin-1β (IL-1β) and interleukin-17A (IL-17A) are inducible factors and important cytokines in the pathogenesis of rheumatoid arthritis (RA). In the present study, three bispecific and neutralizing antibodies (BsAB-1, BsAB-2 and BsAB-3) against both hIL-1β and hIL-17A were constructed, their therapeutic efficacy was compared on collagen induced arthritis (CIA) model mice. In vitro assays demonstrated that the three antibodies could simultaneously bind to target both hIL-1β and hIL-17A. Mice with CIA were subcutaneously administered with one of three antibodies every two days for 29days, we noticed that, compared with the BsAB-2 and BsAB-3, BsAB-1 antibody therapy resulted in more significant effect on alleviating the severity of arthritis by preventing bone damage and cartilage destruction and substantially decreasing production of CII-specific antibodies. In addition, BsAB-1 antibody was more potent in the inhibition of mRNA expression of IL-2, IL-1β, IL-17A, TNF-α and MMP-3 in the spleen of CIA mice compared to the other two. In summary, BsAB-1 is superior over BsAB-2 and BsAB-3 for the treatment of RA model mice, and may be chosen as an ideal candidate for further development of therapeutic drugs for treatment of RA. [Copyright &y& Elsevier]
- Published
- 2014
- Full Text
- View/download PDF
249. Effect of the laser texturing width on hot-pressing joining of AZ31B and CFRTP.
- Author
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Liu, Yifan, Su, Jianhui, Ma, Guolong, Han, Xiaohui, Tan, Caiwang, Wu, Laijun, Chen, Bo, and Song, Xiaoguo
- Subjects
- *
CHEMICAL bonds , *JOINING processes , *MAGNESIUM alloys , *CONTACT angle , *ALLOY texture , *RIVETED joints - Abstract
• Investigate effect of various widths of laser textured groove on the joint. • Identify a new chemical bonding MgCO 3 at the interface after joining. • A number of AZ31B matrix was observed on the CFRTP at the interface. • The joints broke at the CFRTP base material after laser texturing. Laser texturing was performed on the surface of AZ31B magnesium alloy to increase the bonding strength. Textured AZ31B and carbon fiber reinforced thermoplastics (CFRTP) were then joined by the hot-pressing joining process. The effect of various groove widths of laser textured grid on the AZ31B/CFRTP joint was investigated. The research results showed that the wettability of the molten CFRTP on laser textured AZ31B was increased by about nine times, and the contact angle was reduced from 104.0° to 48.8° with a groove width of 0.3 mm. The macroscopic morphology and interface of joints had no defects, when the groove widths were 0.2 mm and 0.3 mm. The tensile-shear test was carried out, and the maximum tensile-shear force of the joint was 2698.8 N in the case of 0.3-mm groove width, which was 2.1 times as much as that of the untreated joint. The maximum tensile-shear force was 65.43% of the CFRTP itself. A diffusion layer of 9 μm– 24 μm thick formed at the AZ31B/CFRTP joint. MgCO 3 was identified at the joining interface. The mechanical interlocking and chemical bonding formed at the interface effectively improved the strength of the joint. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
250. First documentation of seismic stratigraphy and depositional signatures of Zhongsha atoll (Macclesfield Bank), South China Sea.
- Author
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Huang, Xiaoxia, Betzler, Christian, Wu, Shiguo, Bernhardt, Anne, Eagles, Graeme, Han, Xiaohui, and Hovland, Martin
- Subjects
- *
CORAL reefs & islands , *SEA-floor spreading , *STRATIGRAPHIC geology - Abstract
Carbonate platforms form informative archives for paleoclimates and their internal structures can also hold crucial information about the tectonic history and carbonate evolution of the ocean basins. The Zhongsha atoll (Macclesfield Bank) forms the largest atoll system in the South China Sea with a surface area of 23500 km2. However, the internal structure and evolution of this atoll system is completely unknown. 2D multichannel seismic reflection data were acquired in 2017 over the Zhongsha atoll in the South China Sea to unravel the stratigraphy, geomorphology, depositional processes, and seismic facies of one of the world's largest atoll for the first time. This Neogene carbonate platform comprises more than 1 km thick carbonate sequence and overlies a metamorphic basement. The southeastern part of the atoll comprises a fault-controlled graben system, which was formed during the Cenozoic rifting stage of the South China Sea. Most of the faults trend NE-SW and E-W and terminate at or slightly above the top of Middle Miocene strata. Atolls and abundant organic reefs initiated on the positive relief and closely mimicked the underlying topography during the Early Miocene. Shallow-water carbonates continued growing through Middle Miocene to present times. Regional uplift led to subaerial exposure, termination of platform growth and karstification during the Miocene. We also reveal a number of fluid-flow features such as vertical sub-bottom venting features (chimneys and pipes), chaotic reflection zones, which provide the first evidence of active fluid venting in the area of Zhongsha atoll. The Neogene sedimentation history of Zhongsha atoll further provide an important paleoenvironmental context for future scientific drilling to better constrain the evolution of Asia Monsoon. • First documentation of seismic stratigraphy and deposition of Zhongsha atoll (Macclesfield Bank), South China Sea. • Reefs and lagoons developed during the post-rift phase, whose onset is marked by a turning point around the time of the formation of reflector T50. • Three drowning events are identified to tentatively imply three episodes of fast sea floor spreading in the study region. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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