An Improved Mathematical Calculation Method for Beam String Structure Based on Static Equilibrium Principle

Xiangyu Yan,Hong Hu,Zhi-Hua Chen,Yan Yang 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.4

The beam string structure (BSS) has been widely applied to public buildings (e.g. sports venues and exhibition centers) for its strong adaptability to architectural form and reasonable load bearing mechanism. However, most mathematical calculation methods for BSS are too complicated to be generally mastered by structural engineers, which limits the promotion and actual application. In this paper, two analytical calculation methods for the BSS are proposed based on displacement control objectives and work-energy principle. The computational formulas are then derived to calculate the member internal force and structural deformation. On this basis, the tension and static load tests and the fi nite element analytical method have been carried out to assess the calculation methods. The results of the tests and simulation are in good agreement with the analytical solution obtained by the computational formulas. Moreover, the formulas can be more appropriate with a greater beam span, proper rise–span and sag–span ratios (between 1/15 and 1/12) as well as more brace struts.

The sedimentary environment of Early Cretaceous rift basin in eastern China and its response to the Faraoni event

Xiangyu Zhang,Shoujun Li,Xiuli Zhao,Geng Geng,Mingming Yan 한국지질과학협의회 2020 Geosciences Journal Vol.24 No.4

To better understand the sedimentary environment of the rift basin under the influence of a warm global climate, Lingshan Island in eastern Shandong Province (China) was studied. Inorganic geochemical indexes (B, equivalent B, B/Ga, Ga, V, Couch’s palaeosalinity, Adams’s palaeosalinity, Sr/Ba, Sr/Cu, Rb/Sr, Al2O3/MgO, and CaO/MgO·Al2O3) were analyzed and a quantitative calculation of palaeosalinity was carried out based on the Adams and Couch methods. The sedimentary environment of the rift basin at Lingshan Island was determined according to the morphology and distribution of its palaeobiota as well as inorganic geochemical indexes. We demonstrate that eastern China had high-temperature drought-like conditions during the Early Cretaceous, which may have been influenced by the Faraoni event. The dry-hot climate transformed the rift basin at Lingshan Island into saline lacustrine basin. Therefore, the salinization of water was not influenced by seawater but was the response of terrestrial strata to the warm, dry climate. This study helps to understand the sedimentary background of Cretaceous rift basins in eastern China and the influence of a warm climate on China’s terrestrial strata.

Changes in plant anthocyanin levels in response to abiotic stresses: a meta-analysis

Yan Wenjie,Li Juanjuan,Lin Xinyue,Wang Lina,Yang Xiaoxiao,Xia Xiangyu,Zhang Yuxin,Yang Shaoyu,Li Hongbing,Deng Xiping,Ke Qingbo 한국식물생명공학회 2022 Plant biotechnology reports Vol.16 No.5

Anthocyanins are small molecule antioxidants that play important roles in plant response and resistance to abiotic stresses. Their levels increase when plants are exposed to abiotic stress. However, the general response patterns and magnitude of anthocyanin increase, and how they confer resistance to abiotic stresses, are difficult to evaluate because of the influence of experimental variables. In this study, changes in plant anthocyanin content under different abiotic stresses and the effect of anthocyanin overproduction on various physiological indicators were investigated through meta-analysis derived from 1039 datasets of 102 studies. Results showed that among the different stress types, heavy metals, especially copper (Cu) and mercury (Hg), induced the most significant synthesis of anthocyanins. Among the different types of drought treatments, mannitol caused anthocyanin content in plants to increase by 2.4-fold, which was more significant than that of polyethylene glycol and natural drought. Furthermore, UV stress led plant anthocyanins to increase 1.3-fold in C4 plants, which was higher than that in C3 plants. In addition, anthocyanins increased the most when the applied stresses were low and moderate, and of short duration. Moreover, plants overexpressing genes encoding MYB transcription factors increased anthocyanin content by 5.8-fold and significantly improved plant stress tolerance. Among the 21 physiological indicators, glutathione and proline levels increased the most in transgenic plants overproducing anthocyanins when exposed to abiotic stress. Taken together, this meta-analysis indicates that anthocyanins enhance stress tolerance by improving the antioxidant, metal-chelating, and osmoregulatory abilities of the plant. The results presented here can help guide future applications of anthocyanins as plant growth regulators in dryland agriculture and breeding for plant stress tolerance.

Synthesis of acid-activated reversible conversion supramolecular nanoplatform: application in drug delivery and anti-tumor activity

Yang Cuiting,Xiangyu Chen,Jinkui Teng,Shuai Chen,Jianmei Yang,Xiaoqing Liu,Junnan He,Jin Zhang,Yan Zhao 한국고분자학회 2024 Macromolecular Research Vol.32 No.1

Supramolecular nanoplatforms with stimuli-responsive behavior feature sensitive performance and effective drug delivery, which are desirable as intelligent drug delivery systems. Generally, tumor cells are characterized by excessive acid production, resulting in a lower pH in the tumor microenvironment (pH < 6.5) than in normal tissues (pH ≈7.4) and providing the possibility for the drug delivery system to exploit this decrease in pH as a trigger for drug release. Here, an acid-sensitive supramolecular nanoplatform (CM-β-CD/FC12 +Br− NPs) with assembly/disassembly properties was designed and constructed, which was exploited to capture, deliver, and release anti-tumor compound CSL. 2D NOESY was utilized to examine the host–guest interaction and the potential mechanism for CM-β-CD/FC12 +Br− NPs loading CSL. CM-β-CD/FC12 +Br− NPs present good blood compatibility. Cytotoxicity assay revealed that CSL-loaded NPs display minimal toxicity against normal cells BEAS-2B and good anticancer ability against five human cancer cell lines, especially for Human hepatoma cell line SMMC-7721. In addition, cell apoptosis and cycle assay further verified that CSL-loaded NPs-induced apoptosis in SMMC- 7721 cells up to ~ 93%, as well as blocking the cells in G0/G1 phase and inhibiting the proliferation of SMMC-7721 cells in a dose-dependent manner. We expect that CM-β-CD/FC12 +Br− NPs will be potential acid-answered drug delivery candidates.

New Rotor Topologies for Electromagnetic Forces and Acoustic Noise Reduction of claw Pole Alternators

Wu Shuanglong,Yan Xiangyu,Chen Zhaoguo,Zhang Yaodan,Feng Xiao 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.5

This paper proposes a new rotor topology to reduce the electromagnetic forces and acoustic noise of automotive claw pole alternators. A noise bench test was first conducted for a 12-pole/36-slot claw pole alternator and the characteristics of the noise were analyzed. The analytical expression of electromagnetic forces was then derived, and the noise generation mechanism was illustrated theoretically. According to the distribution of the electromagnetic forces on the stator surface, a new rotor structure with rotor claw poles offset was proposed to decrease the force harmonics. Simulation results showed that when the rotor claws of N pole and S pole were offset in the same direction which was consistent with the direction of rotor rotation, the electromagnetic noise would be reduced by 6.7 dB(A), without sacrificing the output current. However, when the rotor claws were offset in the opposite direction, the electromagnetic noise could not be effectively reduced and was even slightly increased. The topology proposed in this paper provides an effective solution for the design and optimization of electromagnetic noise in claw pole alternators.

An Automatic Corona-discharge Detection System for Railways Based on Solar-blind Ultraviolet Detection

Jiaqi Li,Yue Zhou,Xiangyu Yi,Mingchao Zhang,Xue Chen,Muhan Cui,Feng Yan 한국광학회 2017 Current Optics and Photonics Vol.1 No.3

Corona discharge is always a sign of failure processes of high-voltage electrical apparatus, includingthose utilized in electric railway systems. Solar-blind ultraviolet (UV) cameras are effective tools for coronainspection. In this work, we present an automatic railway corona-discharge detection system based on solarblindultraviolet detection. The UV camera, mounted on top of a train, inspects the electrical apparatus,including transmission lines and insulators, along the railway during fast cruising of the train. An algorithmbased on the Hough transform is proposed for distinguishing the emitting objects (corona discharge) fromthe noise. The detection system can report the suspected corona discharge in real time during fast cruises. An experiment was carried out during a routine inspection of railway apparatus in Xinjiang Province, China. Several corona-discharge points were found along the railway. The false-alarm rate was controlled to lessthan one time per hour during this inspection.

Vertebral Artery Variations at the Craniovertebral Junction in “Sandwich” Atlantoaxial Dislocation Patients

Yinglun Tian,Nanfang Xu,Ming Yan,Jinguo Chen,Kan-Lin Hung,Xiangyu Hou,Shenglin Wang,Weishi Li 대한척추신경외과학회 2021 Neurospine Vol.18 No.4

Objective: To summarize the vertebral artery (VA) pattern of 96 “sandwich” atlantoaxial dislocation (AAD) patients and to describe the strategies of reducing the injury of VA during surgery. Methods: From 2009 to 2020, we retrospectively reviewed the 3-dimensional computed tomography angiography data of 96 AAD patients combined with atlas occipitalization and C2–3 fusion, which were diagnosed as “sandwich” AAD and 96 patients as control group patients who were without atlas occipitalization, C2–3 fusion and any other cervical bone deformity at our institution. The variations of each side of VA were described in 3 different parts (C0–1, C1–2, and C2–3) according to the characteristics of the 3-part pathological structures in “sandwich” subgroup. Results: One hundred ninety-two sides of VAs in every group of patients were analyzed and every VA was described separately at 3 different level regions. There were different variations in these 3 different regions: 4 variations in the upper fusion region, 5 variations in the sandwiched region, and 6 variations in the lower fusion region in sandwich AAD patients. And the rate of VA deformity in sandwich AAD patients was much higher and more types of VA variations existed. Conclusion: In “sandwich” AAD patients, deformities of vertebral arteries in craniovertebral junction are more common, and the same VA may have deformities at different levels that severely affect surgical procedures. Therefore, preoperative imaging examination of VA for “sandwich” AAD patients is vital of guiding surgeons to avoid injury of VA during surgery.

Research Progress in SiC-Based Ceramic Matrix Composites

Dong, Shaoming,Wang, Zhen,Zhou, Haijun,Kan, Yan-Mei,Zhang, Xiangyu,Ding, Yusheng,Gao, Le,Wu, Bin,Hu, Jianbao The Korean Ceramic Society 2012 한국세라믹학회지 Vol.49 No.4

SiC-based ceramic matrix composites show many advantages over their monolithic ceramic counterparts, which makes them potential candidates for applications in various fields. Depending strongly on the chemical composition and microstructure of the fiber reinforcement, matrix as well as the fiber/matrix interphase in the material, the properties of ceramic matrix composites(CMCs) are highly tailorable. In this paper, the latest progresses in the interphase design, matrix modification and fiber reinforcement decoration of CMCs are reviewed, their effects on the properties of the CMCs are introduced.

Fluorinated and Charged Non-woven Polypropylene Electret Fiber Membrane: A Novel Way in Transformer Oil Regeneration

Nianrong Zhou,Xiao He,Yuyang Yan,Xinliang Guo,Linshan Zhang,Yunhua He,Xiangyu Tan,Zhengyun Fang 한국전기전자재료학회 2022 Transactions on Electrical and Electronic Material Vol.23 No.2

The regeneration of transformer oil is a trending topic in the dielectric research field. However, the normal way of regeneration requires high cost and complicate process. In this paper, the non-woven polypropylene (PP) electret films were modifi ed by fluorination and corona method to achieve the regeneration function for transformer oil. The results show that the C-H bonds in polypropylene were replaced by C-F bonds during the fluorination process, resulting in the mean diameter of the fibers being decreased to a value of 1.7 μm. The increased roughness of the fi bers leads to super hydrophobicity. Further research revealed that the insulation properties of aging oil recovered after fi ltration by corona charged fl uorinated fi ber membranes. The result is especially signifi cant for breakdown voltage, the values of which reached half of the original insulating oil. In conclusion, the combination of fl uorinating and corona charging method on PP fi ber membrane shows great potential for insulation oil regeneration.

Thermal, Mechanical and Rheological Properties of Poly(lactic acid) Chain Extended with Polyaryl Polymethylene Isocyanate

Yanping Hao,Yi Li,Zhigang Liu,Xiangyu Yan,Yi Tong,Huiliang Zhang 한국섬유공학회 2019 Fibers and polymers Vol.20 No.9

In this study, polyaryl polymethylene isocyanate (PAPI) was used as a chain extender for poly(lactic acid) (PLA)to produce a high molecular weight material with better rheological, thermal and mechanical properties. The reactionbetween PLA chains and PAPI was proved by FTIR during reactive blending. The results showed that the molecular weightand molecular weight distribution were increased with the addition of PAPI content due to the chain extension. Chainextension was also responsible for the increased modulus and complex viscosity. The glass transition temperature (Tg) andthermal stability increased by incorporating with PAPI. The results of mechanical properties showed that a considerablyhigher tensile strength and Young’s modulus of the reactive blends compared with neat PLA.