Research on Whole‑Process Tensile Behavior of Headed Studs in Steel–Concrete Composite Structures

Liang?Dong Zhuang,Hong?Bing Chen,Yuan Ma,Ran Ding 한국콘크리트학회 2021 International Journal of Concrete Structures and M Vol.15 No.4

The headed studs have been widely applied in steel–concrete composite structures as shear connectors. However, the tensile performance of headed studs is also key to the structural performance in many cases such as the semi-rigid composite joints including steel beam–concrete wall joint and steel column–base joint. Therefore, this study presents experimental and analytical study on the whole-process tensile behavior of headed studs. Tests on a total of 33 pullout specimens are first conducted. The tensile capacity and load–deformation behavior of the anchorage concrete, which dominates the structural performance of headed studs, are thoroughly analyzed. In addition, test data in the literature are collected for quantitatively evaluating the influence of embedment depth, bearing area, boundary conditions, and concrete strength on the tensile behavior of the anchorage concrete. On the basis of the influence evaluation, an analytical model represented by a piecewise function is proposed to describe the whole-process load–deformation behavior of the anchorage concrete and validated through the comparison between the predicted curves and all collected experimental results. Then the proposed model is applied to simulate the rotational behavior of the typical semi-rigid joint anchored by headed studs, which takes the contribution of the anchorage concrete into consideration, and is verified by experimental results. The research findings indicate that tensile behavior of anchorage concrete is crucial to the structural performance of semi-rigid joints, even for headed studs with large embedment depth and bearing area.

Sulphonated Reduced Graphene Oxide: A High Performance Anode Material for Lithium Ion Battery

Haibo Li,Rui Niu,Sen Liang,Yulong Ma,Min Luo,Jin Li,Lijun He 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.4

In this work, the sulfonated reduced graphene oxide (SRGO) was synthesized and proposed as an enhanced anode material for lithium ion battery (LIB). The result shows that the SRGO has an improved battery performance (i.e., ~341.7 mAh/g and ~190.6 mAh/g corresponds to SRGO and RGO at the 100th cycle with a current density of 200 mA/g) and superior cycling stability compared with pristine reduced graphene oxide (RGO). These are attributed to the improved specific surface area (448.35 m2 /g) and conductivity (2.5 x 10-4 S/m). Further, the SRGO exhibits good rate capability and excellent energy density at various current densities ranging from 50 mAh/g to 2000 mAh/g, suggesting that SRGO could be a promising anode material for high capacity LIB.

Effects of spherical adsorbent fluidization and self-rotation on removal of VOCs in a cyclonic fluidized bed

Liang Ma,Guolin Xiang,Yuan Huang,Meng-Ya He,Jianping Li,Pengbo Fu 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.85 No.-

Afluidized bed has the advantages of treating largeflows, intensifying mass and heat transfer, andlowering costs. This study proposed a cyclonicfluidized bed packed with spherical activated carbonadsorbents for volatile organic compounds adsorption. Thefluidization and self-rotation of the ACparticles in a 25 mm cyclonicfluidized bed were studied with high-speed camera testing technology. Theeffects of the particle movement on the adsorption efficiency of toluene were also tested. The resultsshow that most of the particles at the inlet side of the cyclonicfluidized bed were moving up when theinlet airflow rate was greater than 2.0 m3/h. The particles began to move in clusters when the relativepacking height increased to a critical value of 0.57. Increasing the gasflow rate and the diameter andheight of the core column will increase the self-rotation speed of the total particles. The maximum selfrotationspeed of spherical adsorbents reached 1700 rad/s at the inletflow rate of 2.5 m3/h. In the case ofthe same axial velocity of the gas phase in the upper space of the core column, increasing the particle selfrotationspeed can slightly improve the adsorption efficiency. The maximum adsorption efficiencyreached 99% when the inletflow rate is 1.0 m3/h with relative packing height 0.65.

MiR-454 Prompts Cell Proliferation of Human Colorectal Cancer Cells by Repressing CYLD Expression

Liang, Hong-Liang,Hu, Ai-Ping,Li, Sen-Lin,Xie, Jia-Ping,Ma, Qing-Zhu,Liu, Ji-Yong Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Previous studies have shown that miR-454 plays an important role in a variety of biological processes in various human cancer cells. However, the underlying mechanisms of this microRNA in colorectal cancer (CRC) cells remain largely unknown. In the present study, we investigated the miR-454 role in CRC cell proliferation. We found that miR-454 expression is markedly upregulated in CRC tissues and CRC cells compared with the matched tumor adjacent tissues and the FHC normal colonic cell line. Ectopic expression of miR-454 promoted the proliferation and anchorage-independent growth of CRC cells, whereas inhibition of miR-454 reduced this effect. Bioinformatics analysis further revealed cylindromatosis (CYLD), a putative tumor suppressor as a potential target of miR-454. Data from luciferase reporter assays showed that miR-454 directly binds to the 3'-untranslated region (3'-UTR) of CYLD mRNA and repressed expression at both transcriptional and translational levels. In functional assays, CYLD-silenced in miR-454-in-transfected SW480 cells have positive effect to promote cell proliferation, suggesting that direct CYLD downregulation is required for miR-454-induced CRC cell proliferation. In sum, our data provide compelling evidence that miR-454 functions as an onco-miRNA, playing a crucial role in the promoting cell proliferation in CRC, and its oncogenic effect is mediated chiefly through direct suppression of CYLD expression.

CO2 capture and preparation of spindle-like CaCO3 crystals for papermaking using calcium carbide residue waste via an atomizing approach

Liang Ma,Tingyu Yang,Yu Wu,Xiaoqing Yue,Jinrong Yang,Shuai Zhang,Qiang Li,Jianbin Zhang 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.9

Spindle-like CaCO3 crystals with controllable sizes for papermaking were successfully prepared using CO2 (8% CO2/N2 mixture gas) and calcium carbide residue (CCR) waste, a by-product of acetylene gas and polyvinyl chloride production, as the raw materials by an atomization method at room temperature. The influences of solution concentration, reaction temperature, and gas/liquid flow rate ratios on the properties of the CaCO3 crystal were systematically investigated, and a possible atomization mechanism was proposed. The size of the as-prepared CaCO3 crystal with pure calcite phase was turned from 4.71×4.02 μm to 1.82×1.12 μm by adjusting the reaction conditions. The application of the as-prepared CaCO3 crystals from CCR waste as a filler for papermaking was explored. The R475 blue light whiteness of paper was increased from 77.3 to 80.6 with 11.4% CaCO3 crystals

Control Over the Branched Structures of Platinum Nanocrystals for Electrocatalytic Applications

Ma, Liang,Wang, Chengming,Gong, Ming,Liao, Lingwen,Long, Ran,Wang, Jinguo,Wu, Di,Zhong, Wei,Kim, Moon J.,Chen, Yanxia,Xie, Yi,Xiong, Yujie American Chemical Society 2012 ACS NANO Vol.6 No.11

<P>Structural control of branched nanocrystals allows tuning two parameters that are critical to their catalytic activitythe surface-to-volume ratio, and the number of atomic steps, ledges, and kinks on surface. In this work, we have developed a simple synthetic system that allows tailoring the numbers of branches in Pt nanocrystals by tuning the concentration of additional HCl. In the synthesis, HCl plays triple functions in tuning branched structures <I>via</I> oxidative etching: (i) the crystallinity of seeds and nanocrystals; (ii) the number of {111} or {100} faces provided for growth sites; (iii) the supply kinetics of freshly formed Pt atoms in solution. As a result, tunable Pt branched structurestripods, tetrapods, hexapods, and octopods with identical chemical environmentcan be rationally synthesized in a single system by simply altering the etching strength. The controllability in branched structures enables to reveal that their electrocatalytic performance can be optimized by constructing complex structures. Among various branched structures, Pt octopods exhibit particularly high activity in formic acid oxidation as compared with their counterparts and commercial Pt/C catalysts. It is anticipated that this work will open a door to design more complex nanostructures and to achieve specific functions for various applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2012/ancac3.2012.6.issue-11/nn304237u/production/images/medium/nn-2012-04237u_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn304237u'>ACS Electronic Supporting Info</A></P>

Dense baryonic matter in conformally-compensated hidden local symmetry: Vector manifestation and chiral symmetry restoration

Ma, Yong-Liang,Harada, Masayasu,Lee, Hyun Kyu,Oh, Yongseok,Park, Byung-Yoon,Rho, Mannque American Physical Society 2014 PHYSICAL REVIEW D - Vol.90 No.3

Different Catabolism Pathways Triggered by Various Methylxanthines in Caffeine-Tolerant Bacterium Pseudomonas putida CT25 Isolated from Tea Garden Soil

( Yi-xiao Ma ),( Xiao-han Wu ),( Hui-shi Wu ),( Zhan-bo Dong ),( Jian-hui Ye ),( Xin-qiang Zheng ),( Yue-rong Liang ),( Jian-liang Lu ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.7

The degradation efficiency and catabolism pathways of the different methylxanthines (MXs) in isolated caffeine-tolerant strain Pseudomonas putida CT25 were comprehensively studied. The results showed that the degradation efficiency of various MXs varied with the number and position of the methyl groups on the molecule (i.e., xanthine > 7-methylxanthine ≈ theobromine > caffeine > theophylline > 1-methylxanthine). Multiple MX catabolism pathways coexisted in strain CT25, and a different pathway would be triggered by various MXs. Demethylation dominated in the degradation of N-7-methylated MXs (such as 7- methylxanthine, theobromine, and caffeine), where C-8 oxidation was the major pathway in the catabolism of 1-methylxanthine, whereas demethylation and C-8 oxidation are likely both involved in the degradation of theophylline. Enzymes responsible for MX degradation were located inside the cell. Both cell culture and cell-free enzyme assays revealed that N-1 demethylation might be a rate-limiting step for the catabolism of the MXs. Surprisingly, accumulation of uric acid was observed in a cell-free reaction system, which might be attributed to the lack of activity of uricase, a cytochrome c-coupled membrane integral enzyme.

Effects of Green Tea on Blood Pressure and Hypertension-induced Cardiovascular Damage in Spontaneously Hypertensive Rat

Yue-Rong Liang,Shi-Cheng Ma,Xin-Qiang Zheng,Jing-Yi Xu,Ming-Yan Wu,Yi-Wen Luo,Xian-Yang Luo,Jian-Liang Lu 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.1

Three groups of spontaneously hypertensive rats were administered by gavage with distilled water (control group), low-dose green tea (LGT, 0.2 g/kg BW·day) and high-dose green tea (HGT, 1.0 g/kg BW·day) for 4 weeks,during which systolic blood pressure (SBP) was measured weekly by non-invasive tail-cuff method. At the end of experiment, left ventricular hypertrophy index (LHVI) and plasma biochemical indicators were determined, and ultrastructures of myocardium and aortic vascular smooth muscle cells were observed by transmission electron microscopy (TEM). The results show that green tea gavage suppressed the increase in SBP, along with decline in levels of plasma nitric oxide, aldosterone, malondialdehyde, and LHVI, but increased levels of plasma creatinine, calcitonin gene-related peptide, and glutathione peroxidase in a dose dependant manner. Green tea had no effect on plasma total cholesterol. TEM shows that green tea gavage protected mitochondria of left ventricular myocardium and aortic vascular smooth muscle cells from damage.

A newly characterized exopolysaccharide from Sanghuangporus sanghuang

Xiao-kui Ma,Xu She,Eric Charles Peterson,Yu Zhen Wang,Peng Zheng,Hongyan Ma,Kexin Zhang,Jian Liang 한국미생물학회 2019 The journal of microbiology Vol.57 No.9

Sanghuangporus sanghuang is a well-known pharmacodynamic and economically important edible fungus associated with mulberry (Morus spp.). A distinctly new exopolysaccharide (EPS), designated SHP-2 was obtained from S. sanghuang P0988 broth, and its structure and anti-aging prosperity were characterized. SHP-2 was found to be composed of a backbone of 4)-β-Manp-(1 4)-α-Araf-(1 3,4)-α-Glcp(1 3,4)-α-Glcp-(1 3,4)-α-Glcp-(1 3,4)-α-Glcp-(1 3,4)-α- Glcp-(1 6)-α-Galp-(1 4)-β-Manp-(1 and five branches, including four α-D-Glcp-(1 and one α-D-Manp-(1 SHP-2 was shown to increase antioxidant enzyme activities including catalase (CAT) and superoxide dismutase (SOD) activities, as well as trolox equivalent antioxidant (TEAC) capacity in serum of mice pre-treated with D-Gal, while reducing lipofuscin levels. SHP-2 exerted a favorable influence on immune organ coefficients and ameliorated the histopathological hepatic lesions and apoptosis in hepatocytes of Dgalactose- aged mice almost in a dose-dependent manner. Using the same analytical methods, on comparison with previously studied EPS compounds (i.e. SHP-1), SHP-2 was found to have more complex structure, larger molecule weight, and different anti-aging properties. The results presented here suggest that not only does EPS bioactivity vary with respect to molecular structures and molecule weight, but that multiple structures with different activity can be expressed by a single fungal strain. These results may help understanding the antiaging prosperity of these polysaccharides for use in health foods or dietary supplements.