http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Structural behavior of sandwich composite wall with truss connectors under compression
Ying Qin,Xin Chen,Xingyu Zhu,Wang Xi,Yuanze Chen 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.35 No.2
Sandwich composite wall consists of concrete core attached by two external steel faceplates. It combines the advantage of steel and concrete. The appropriate composite action between steel faceplate and concrete core is achieved by using adequate mechanical connectors. This research studied the compressive behavior of the sandwich composite walls using steel trusses to bond the steel faceplates to concrete infill. Four short specimens with different wall width and thickness of steel faceplate were designed and tested under axial compression. The test results were comprehensively evaluated in terms of failure modes, load versus axial and lateral deformation responses, resistance, stiffness, ductility, strength index, and strain distribution. The test results showed that all specimens exhibited high resistance and good ductility. Truss connectors offer better restraint to walls with thinner faceplates and smaller wall width. In addition, increasing faceplate thickness is more effective in improving the ultimate resistance and axial stiffness of the wall.
Song, Yingze,Zhao, Wen,Zhu, Xingyu,Zhang, Li,Li, Qiucheng,Ding, Feng,Liu, Zhongfan,Sun, Jingyu American Chemical Society 2018 ACS APPLIED MATERIALS & INTERFACES Vol.10 No.18
<P>The lithium-sulfur (Li-S) battery has been deemed as one of the most promising energy-storage systems owing to its high energy density, low cost, and environmental benignancy. However, the capacity decay and kinetic sluggishness stemming from polysulfide shuttle effects have by far posed a great challenge to practical performance. We herein demonstrate the employment of low-cost, wet-chemistry-derived VO<SUB>2</SUB> nanobelts as the effective host additives for the graphene-based sulfur cathode. The VO<SUB>2</SUB> nanobelts displayed an ultrafast anchoring behavior of polysulfides, managing to completely decolor the polysulfide solution in 50 s. Such a fast and strong anchoring ability of VO<SUB>2</SUB> was further investigated and verified by experimental and theoretical investigations. Benefitting from the synergistic effect exerted by VO<SUB>2</SUB> in terms of chemical confinement and catalytic conversion of polysulfides, the Li-S batteries incorporating VO<SUB>2</SUB> and graphene manifested excellent cycling and rate performances. Notably, the batteries delivered an initial discharge capacity of 1405 mAh g<SUP>-1</SUP> when cycling at 0.2 C, showed an advanced rate performance of ∼830 mAh g<SUP>-1</SUP> at 2 C, and maintained a stable cycling performance at high current densities of 1, 2, and 5 C over 200 cycles, paving a practical route toward cost-effective and environmentally benign cathode design for high-energy Li-S batteries.</P> [FIG OMISSION]</BR>
Eccentric compressive behavior of novel composite walls with T-section
Ying Qin,Xin Chen,Wang Xi,Xingyu Zhu,Yuanze Chen 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.35 No.4
Double skin composite walls are alternatives to concrete walls to resist gravity load in structures. The composite action between steel faceplates and concrete core largely depends on the internal mechanical connectors. This paper investigates the structural behavior of novel composite wall system with T section and under combined compressive force and bending moment. The truss connectors are used to bond the steel faceplates to concrete core. Four short specimens were designed and tested under eccentric compression. The influences of the thickness of steel faceplates, the truss spacing, and the thickness of web wall were discussed based on the test results. The N-M interaction curves by AISC 360, Eurocode 4, and CECS 159 were compared with the test data. It was found that AISC 360 provided the most reasonable predictions.
Behavior of L-shaped double-skin composite walls under compression and biaxial bending
Ying Qin,Xin Chen,Wang Xi,Xingyu Zhu,Yuanze Chen 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.37 No.4
The application of double-skin composite wall should meet different layout plans. However, most available research focused on the rectangular section with uniform axial compression. In this research, the structural behavior of double-skin composite wall with L section was studied. Due to the unsymmetric geometric characteristics, the considered loading condition combined the axial compression and biaxial bending. Five specimens were designed and tested under eccentric compression. The variables in the test included the width of the web wall, the truss spacing, the thickness of the steel faceplate, and the thickness of the web wall. The test results were discussed in terms of the load-displacement responses, buckling behavior, stiffness, ductility, strength utilization, strain distribution. Two modern codes were employed to predict the interaction between the axial compression and the biaxial bending. The method to calculate the available bending moment along the two directions was proposed. It was found that CECS 159:2004 offers more suitable results than AISC 360.
Computational Studies on Mesh Stiffness of Paralleled Helical Beveloid Gear Pair
Ruihua Sun,Chaosheng Song,Caichao Zhu,Yawen Wang,Xingyu Yang 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.1
Considering the asymmetrical left and right tooth profiles including the transient curve at the tooth root region and the varying thickness along the axial direction due to the cone angle, we build the accurate profile curve model including the transient curve at the tooth root of helical beveloid gear with machining parameters to solve the problem of non-applicability of real digital model. According to the feature of gear shape varying along tooth width direction, we introduced the slicing method and derived its grouping formula. Finally, the efficient and accurate slicing-based mesh stiff ness calculation model of paralleled helical beveloid gears was proposed using potential energy theory. Then, mesh stiff ness was calculated using finite element contact model for comparison and verification. Finally, the impacts of macro geometry parameters including cone angle, normal pressure angle, helix angle, tooth width and addendum coefficient on single and total mesh stiff ness were analyzed. The calculated mesh stiff ness correlates well with the results from FEM with the maximum peak error is 4.8%. Results show that the tooth width shows an obvious incremental impact on average total mesh stiff ness. When the pressure angle, helix angle, cone angle and addendum coefficient increase, the average total mesh stiff ness increases first and then decreases. For the fluctuating value, it increases as the tooth width, helix angle and cone angle increase. However, the pressure angle and addendum coefficient show an opposite impact on the fluctuating value.
Song, Yingze,Zhao, Wen,Kong, Long,Zhang, Li,Zhu, Xingyu,Shao, Yuanlong,Ding, Feng,Zhang, Qiang,Sun, Jingyu,Liu, Zhongfan The Royal Society of Chemistry 2018 ENERGY AND ENVIRONMENTAL SCIENCE Vol.11 No.9
<P>Lithium-sulfur (Li-S) batteries are deemed as one of the most promising next-generation energy storage systems. However, their practical application is hindered by existing drawbacks such as poor cycling life and low Coulombic efficiency due to the shuttle effect of lithium polysulfides (LiPSs). We herein present an <I>in situ</I> constructed VO2-VN binary host which combines the merits of ultrafast anchoring (VO2) with electronic conducting (VN) to accomplish smooth immobilization-diffusion-conversion of LiPSs. Such synchronous advantages have effectively alleviated the polysulfide shuttling, promoted the redox kinetics, and hence improved the electrochemical performance of Li-S batteries. As a result, the sulfur cathode based on the VO2-VN/graphene host exhibited an impressive rate capability with ∼1105 and 935 mA h g<SUP>−1</SUP> at 1C and 2C, respectively, and maintained long-term cyclability with a low capacity decay of 0.06% per cycle within 800 cycles at 2C. More remarkably, favorable cyclic stability can be attained with a high sulfur loading (13.2 mg cm<SUP>−2</SUP>). Even at an elevated temperature (50 °C), the cathodes still delivered superior rate capacity. Our work emphasizes the importance of immobilization-diffusion-conversion of LiPSs toward the rational design of high-load and long-life Li-S batteries.</P>