Research on the Compression Behavior of Steel Reinforced Concrete Columns With Built-in Steel Tubes

Cun Hui,Fan Zhang,Zhizeng Zhang,Xiaoli Liu,Ran Hai,John J. Myers 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.4

In order to study the compression behavior of rectangular steel reinforced concrete columns with built-in steel tubes under diff erent eccentric loads, three 1/10 scale specimens were designed and monotonic loading tests were carried out on them. The dimensions, steel bars and steel tube of the three specimens were the same except for the location of the loading point. The eccentricity ratios of the three specimens were 0, 0.25 and 0.5, respectively. The failure modes, load-bearing capacity and displacement characteristics of the test specimens were analyzed. According to the Chinese code, the load-bearing capacity calculation principles and methods of steel reinforced concrete columns with built-in steel tube were investigated for the comparison. The study shows that the peak vertical loads of specimens decrease and the corresponding vertical and horizontal peak displacement increase as the eccentricity increases. The load-bearing capacity calculation results from Chinese code are slightly smaller than the test result because of the unconsidered sleeve eff ect of the internal steel tube. The errors between them are small, and the calculation methods are benefi cial to ensure the structural safety.

A full path assessment approach for vibration serviceability and vibration control of footbridges

Qiankun Zhu,Xiaoli Hui,Yongfeng Du,Qiong Zhang 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.70 No.6

Most of the existing evaluation criteria of vibration serviceability rely on the peak acceleration of the structure rather than that of the people keeping their own body unmoved on the structure who is the real receiver of structural vibrations. In order to accurately assess the vibration serviceability, therefore, a full path assessment approach of vibration serviceability based on vibration source, path and receiver is not only tentatively proposed in this paper, taking the peak acceleration of receiver into account, but also introduce a probability procedure to provide more instructive information instead of a single value. In fact, semi-rigid supported on both sides of the structure is more consistent with the actual situation than simply supported or clamped due to the application of the prefabricated footbridge structures. So, the footbridge is regarded as a beam with semi-rigid supported on both sides in this paper. The differential quadrature-integral quadrature coupled method is not only to handle different type of boundary conditions, but also after being further modified via the introduction of an approximation procedure in this work, the time-varying system problem caused by human-structure interaction can be solved well. The analytical results of numerical simulations demonstrate that the modified differential quadrature-integral quadrature coupled method has higher reliability and accuracy compared with the mode superposition method. What’s more, both of the two different passive control measures, the tuned mass damper and semi-rigid supported, have good performance for reducing vibrations. Most importantly, semi-rigid supported is easier to achieve the objective of reducing vibration compared with tuned mass damper in design stage of structure.

Tiny Basic Nickel Carbonate Arrays/Reduced Graphene Oxide Composite for High-Efficiency Supercapacitor Application

Zhengmin Yu,Xiaoli Su,Denghu Wei,Shu-Juan Yao,Huiyan Ma,Hui Zhao,Xipeng Pu,Wenzhi Li,Jie Wang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.4

3D structure composite made of tiny basic nickel carbonate arrays on the surface of reduced graphene oxide nanosheets (G-NiCH) are prepared by the hydrothermal method. The specific surface area of the G-NiCH composites is twice that of single basic nickel carbonate, which is due to the tiny basic nickel carbonate arrays structure wherein each individual nanoneedle is about 20 nm in length and 2 nm in width. The G-NiCH electrodes display high-efficiency electrochemical performance with good specific capacitance (1230 F g -1) and excellent stability (100% capacitance retention after 2000 cycles). This is attributed to the synergistic effect that reduced graphene oxide offer fast electron transmission path and basic nickel carbonate act as high effective active material.

Study on the Vertical Dynamic Coupled Effects of the Crowd-structure System based on the Social Force Model

Qiankun Zhu,Xiaoli Hui,Nana Nan,Yongfeng Du 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.5

Due to the complexity and randomness of the crowd motion, it is not easy to establish the crowd-structure coupled governing equation. Therefore, the idea of the solution procedure for the coupled system of the single pedestrian and structure is extended to carry out the research of crowd-structure coupled system. Then based on the social force model and the deceleration mechanism aswell as the self-stopped mechanism, the one-way pedestrian flow is simulated. The modified Differential Quadrature-Integral Quadrature (DQ-IQ) mixed method is used to solve the dynamic response of the structure under the moving stiffness-mass-damping model, which can demonstrate this method enjoys higher accuracy than the mode superposition method and can take enough higher modes into consideration. Additionally, the fact that the DQ-IQ mixed method can be used to solve the dynamic response of the structure subjected to the crowd is verified. The final results under random crowd show that the varying tendencies of structural modal parameters respectively changed with the the number of pedestrian acting on the structure, In order to more comprehensively and more scientifically measure the vibration function of the structure, the 1 s-RMS acceleration is introduced to weaken the interference effect of random fluctuation.

Monitoring the Bifurcated Recurrent Laryngeal Nerve

Hoon Yub Kim,Xiaoli Liu,Hui Sun,Young Jun Chai,Woong Youn Chung,Gianlorenzo Dionigi 대한갑상선-내분비외과학회 2017 The Koreran journal of Endocrine Surgery Vol.17 No.2

Anatomical anomalies of the recurrent laryngeal nerve (RLN) can not only mean an operational challenge in thyroid operations for the endocrine surgeon, but also an increased risk of postoperative vocal cord paralysis (VCP). Atypical courses of the RLN are frequent and observed in about a quarter of the thyroid gland operations. Anatomical RLN variations are represented by an atypical RLN pattern as anterior or lateral to the thyroid gland, an anteriorly RLN to a Zuckerkandl tuberculum nodule, a fixed, splayed, or entrapped RLN with capsular association through fascial bands, an invaded RLN, a nerve posterior to ligament of Berry, a thin <1 mm nerve, or antevascular RLN, a non-RLN, a ramificated RLN. Anatomical variations of RLN rarely can be identified preoperatively. The bifurcated RLN represent a significant anatomical variation because prevention of VCP requires preservation of all branches of the RLN. An awareness of the surgical anatomy and the possible dispositions and ramifications of the RLN is very helpful in avoiding its injury during thyroidectomy. The current report derives from a review of the literature and personal experience on identification, confirmation, and monitoring the bifurcated RLN.

Medico-Legal Issues of Intraoperative Neuromonitoring in Thyroid Surgery

Hoon Yub Kim,Xiaoli Liu,Hui Sun,Che-Wei Wu,Young Jun Chai,Woong Youn Chung,Ralph Tufano,Henning Dralle,Matteo Lavazza,Gianlorenzo Dionigi 대한갑상선-내분비외과학회 2017 The Koreran journal of Endocrine Surgery Vol.17 No.2

Advances in intraoperative neuromonitoring (IONM) in thyroid surgery have provided significant insights into recurrent laryngeal nerve function during thyroid surgery. Despite the limitations and necessary caution when using intraoperative monitors to interpret neural function, these technologies have been definite steps in the right direction for assessing neural integrity and safe surgical strategy during thyroid operations. The techniques discussed minimize the adverse sequelae of a variety of thyroid gland procedures, reducing the morbidity rates/risks in the perioperative period. Furthermore, it is likely that such monitoring will become a standard of care. Accurate, reliable and continuous monitoring is essential, and on-going large studies with definable end points will be necessary. The use of monitoring, such as continuous one, may improve cost efficiency by reducing permanent nerve injuries. A danger in this process, however, is the potential for public opinion, outside regulatory bodies, or medico-legal implications to drive change and enforce standards of care before appropriate data are available.

Effect of Broussonetia papyrifera L. (paper mulberry) silage on dry matter intake, milk composition, antioxidant capacity and milk fatty acid profile in dairy cows

Si, Bingwen,Tao, Hui,Zhang, Xiaoli,Guo, Jiangpeng,Cui, Kai,Tu, Yan,Diao, Qiyu Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.8

Objective: This study was carried out to investigate the possible application of Broussonetia papyrifera (B. papyrifera) silage as a functional feeding stuff in dairy cattle. Methods: Seventy-two Holstein cows were divided into four groups randomly and allocated to 6 pens with 3 individuals in each group and fed the original total mixed ratio (TMR) in the dairy farm or the new TMR with 5%, 10%, and 15% B. papyrifera silage, separately. Feed intake were recorded, milk and blood samples were collected, and milk composition, blood metabolites and milk fatty acids composition were measure at the end of the experiment. Results: Dry matter intake of cows decreased when they fed on diet with B. papyrifera, but no differences were observed in body condition score, milk yield, milk protein and lactose, feed efficiency and serum metabolites between groups. Both 10% or 15% of B. papyrifera silage in the diet significantly increased the immunoglobulin A (IgA) and IgG in serum, 15% of B. papyrifera silage increased the content of serum catalase, superoxide dismutase, total antioxidant capacity, and decreased the content of 8-hydroxy-2'-deoxyguanosine. Furthermore, 10% or 15% of B. papyrifera silage resulted in a significant decrease in the milk somatic cell count, and increased the polyunsaturated fatty acids content in the milk. Conclusion: The diets with 10% to 15% of B. papyrifera silage might enhance the immune and antioxidant function of dairy cows and increase the polyunstaturated fatty acid concentration in the milk.

AMPK alleviates high uric acid-induced Na+-K+-ATPase signaling impairment and cell injury in renal tubules

Jing Xiao,Sibo Zhu,Haochen Guan,Haochen Guan,Fengqin Li,Xiaoli Zhang,Hui Guo,Xiaojun Wang,Zhibin Ye 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

One of the mechanisms in hyperuricemia (HUA)-induced renal tubular injury is the impairment of Na+-K+-ATPase (NKA) signaling, which further triggers inflammation, autophagy, and mitochondrial dysfunction and leads to cell injury. Here, we used RNA sequencing to screen the most likely regulators of NKA signaling and found that the liver kinase B1(LKB1)/adenosine monophosphate (AMP)-activated protein kinase (AMPK)/ mammalian target of rapamycin (mTOR) pathway was the most abundantly enriched pathway in HUA. AMPK is a key regulator of cell energy metabolism; hence, we examined the effect of AMPK on HUA-induced dysregulation of NKA signaling and cell injury. We first detected AMPK activation in high uric acid (UA)-stimulated proximal tubular epithelial cells (PTECs). We further found that sustained treatment with the AMPK activator 5-aminoimidazole-4-carboxamide 1-β-d-ribofuranoside (AICAR), but not the AMPK inhibitor Compound C, significantly alleviated UA-induced reductions in NKA activity and NKA α1 subunit expression on the cell membrane by reducing NKA degradation in lysosomes; sustained AICAR treatment also significantly alleviated activation of the NKA downstream molecules Src and interleukin-1β (IL-1β) in PTECs. AICAR further alleviated high UA-induced apoptosis, autophagy, and mitochondrial dysfunction. Although AMPK activation by metformin did not reduce serum UA levels in hyperuricemic rats, it significantly alleviated HUAinduced renal tubular injury and NKA signaling impairment in vivo with effects similar to those of febuxostat. Our study suggests that AMPK activation may temporarily compensate for HUA-induced renal injury. Sustained AMPK activation could reduce lysosomal NKA degradation and maintain NKA function, thus alleviating NKA downstream inflammation and protecting tubular cells from high UA-induced renal tubular injury.

Constructing mixed matrix membranes for CO2 separation based on light lanthanide fluoride nanosheets with mesoporous structure

Yanli Zhang,Meixue Zhao,Xu Li,Qingping Xin,Xiaoli Ding,Lizhi Zhao,Hui Ye,Ligang Lin,Hong Li,Yuzhong Zhang 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.125 No.-

The incorporation of porous nano-fillers into mixed matrix membranes (MMMs) has a great impact onCO2 separation. In this study, a series of F-Ln (Ln is the Light Lanthanide, Ln = La, Ce, Pr, Nd) nanosheetswith mesoporous structure was fabricated as a filler in Pebax1657 matrix to improve the performance ofCO2 separation. F-Ln nanosheets are uniformly distributed in the membrane and the mesoporous structurecan construct multiple channels for CO2 fast transport in Pebax/F-Ln MMMs. The pore diameter ofnanosheet is in order: F-La > F-Ce > F-Pr > F-Nd, and the smaller pore diameter of nanosheets is beneficialto improve the CO2 separation performance. In humidified conditions, Pebax/F-Nd-6 MMMs show optimumseparation performance among MMMs, and the CO2 permeability is up to 1265 Barrer and CO2/CH4selectivity is 36.7, which are 2.3 times and 1.9 times higher than pure Pebax and approaches 2019 upperbound. Meanwhile, to demonstrate the potential universal applicability of F-Ln nanosheets in CO2 separation,XLPEO/F-Ce MMMs were fabricated to separate CO2/N2 and the performance exceeds the 2019upper bound. The efficient CO2 separation performance of 2D F-Ln nanosheets with mesoporous structurein membranes reveals the potential application of these nanosheets in industrial CO2 separation.

Laccase-Mediated In Situ Oxidation of Dopamine for Dyeing of Human Hair

Weini Jia,Shirong Li,Zhengxin Luo,Hainan Yu,Wenjun Zhu,Wenjun Zhu,Qing-hui Mao,Xiaoli Zhang,Zhi-jie Liang,Aixue Dong 한국섬유공학회 2021 Fibers and polymers Vol.22 No.1

Due to the damage of scalp because of chemical dyes, increasing attention had been paid to the ecological dyeingof human hair. To address the need for ecological restoration and dyeing of human hair, herein, a novel approach has beenproposed via laccase-mediated in situ oxidation of dihydroxy phenylalanine (dopamine). As laccase can catalyze dopamineoxidation and then polymerization to produce strongly colored polymers, different biological coloration processes of humanhair based on this process were investigated: (i) Human hair was treated with laccase alone; (ii) The absorption of human hairwith dopamine, followed by further catalysis of air; (iii) The absorption of human hair with dopamine, followed by furthercatalysis of laccase; (iv) Simultaneous laccase-mediated polymerization and dyeing of human hair; and (v) Polymerization ofDopamine with laccase and then dyeing human hair. The surface properties of dyed hair were evaluated in terms of ultraviolet(UV)-protection, color fastness, Fourier transforming infrared spectrum (FT-IR), optical microscope, and scanning electronmicroscopy (SEM). The results show that best hair dyeing effect was achieved via simultaneous laccase-mediatedpolymerization and dyeing. The dyed hair obtained K/S values of 28, light fastness of level 5, and UPF of 100+. The opticalmicroscope and SEM observations show that the surface of colored hair fibers was covered with thin burrs, which can beattributed to polydopamine attached with physical adhesive force and covalent reaction. FT-IR analysis shows that functionalgroups were present on the surface of the dyed hair which can be considered as introduction of hydroxyl radical groups. Thisbiological stain technique may be widely used in dyeing of hair with black color.