Evaluation of early age mechanical properties of concrete in real structure

Jiachun Wang,Peiyu Yan 사단법인 한국계산역학회 2013 Computers and Concrete, An International Journal Vol.12 No.1

The curing temperature is known to influence the rate of mechanical properties development of early age concrete. In realistic sites the temperature of concrete is not isothermal 20˚C, so the paper measured adiabatic temperature increases of four different concretes to understand heat emission during hydration at early age. The temperature-matching curing schedule in accordance with adiabatic temperature increase is adopted to simulate the situation in real massive concrete. The specimens under temperature-matching curing are subjected to realistic temperature for first few days as well as adiabatic condition. The mechanical properties including compressive strength, splitting strength and modulus of elasticity of concretes cured under both temperature-matching curing and isothermal 20˚C curing are investigated. The results denote that comparing temperature-matching curing with isothermal 20˚C curing, the early age concretes mechanical properties are obviously improved, but the later mechanical properties of concretes with pure Portland and containing silica fume are decreased a little and still increased for concretes containing fly ash and slag. On this basement using an equivalent age approach evaluates mechanical properties of early age concrete in real structures, the model parameters are defined by the compressive strength test, and can predict the compressive strength, splitting strength and elasticity modulus through measuring or calculating by finite element method the concreted temperature at early age, and the method is valid, which is applied in a concrete wall for evaluation of crack risking.

High-breakdown-voltage GaN-based vertical FinFET design

Zilong Wang,Liang Liu,Peiyue Qi,Jiawei Chen,Lixia Zhao 전력전자학회 2024 JOURNAL OF POWER ELECTRONICS Vol.24 No.3

In this study, GaN-based vertical FinFET device using HfO 2 as a high-κ dielectric gate layer to improve the breakdown voltage is designed. Simulation results show that a breakdown voltage as high as 2139 V can be achieved for the optimized GaN-based FinFET with a fin channel width of 200 nm, a channel doping concentration of 1 × 10 16 cm −3 , and a drift layer thickness of 10 μm. In addition, the proposed device has a low specific on-state resistance of 0.84 mΩ cm 2 , resulting in a large Baliga optimum figure of merit (FOM) 5.45 GW cm −2 . This work could lay a foundation to further improve the electrical performance of GaN-based vertical FinFET devices.

Novel artesunate-metformin conjugate inhibits bladder cancer cell growth associated with Clusterin/SREBP1/FASN signaling pathway

Lin Peiyu,Yang Xiyue,Wang Linghui,Zou Xin,Mu Lingli,Xu Cangcang,Yang Xiaoping 대한약리학회 2024 The Korean Journal of Physiology & Pharmacology Vol.28 No.3

Bladder cancer remains the 10th most common cancer worldwide. In recent years, metformin has been found to have potential anti-bladder cancer activity while high concentration of IC50 at millimolar level is needed, which could not be reached by regular oral administration route. Thus, higher efficient agent is urgently demanded for clinically treating bladder cancer. Here, by conjugating artesunate to metformin, a novel artesunate-metformin dimer triazine derivative AM2 was designed and synthesized. The inhibitory effect of AM2 on bladder cancer cell line T24 and the mechanism underlying was determined. Anti-tumor activity of AM2 was assessed by MTT, cloning formation and wound healing assays. Decreasing effect of AM2 on lipogenesis was determined by oil red O staining. The protein expressions of Clusterin, SREBP1 and FASN in T24 cells were evaluated by Western blotting. The results show that AM2 significantly inhibited cell proliferation and migration at micromolar level, much higher than parental metformin. AM2 reduced lipogenesis and down-regulated the expressions of Clusterin, SREBP1 and FASN. These results suggest that AM2 inhibits the growth of bladder cancer cells T24 by inhibiting cellular lipogenesis associated with the Clusterin/SREBP1/FASN signaling pathway.

PEO based polymer-ceramic hybrid solid electrolytes: a review

Feng Jingnan,Wang Li,Chen Yijun,Wang Peiyu,Zhang Hanrui,He Xiangming 나노기술연구협의회 2021 Nano Convergence Vol.8 No.2

Compared with traditional lead-acid batteries, nickel–cadmium batteries and nickel-hydrogen batteries, lithium-ion batteries (LIBs) are much more environmentally friendly and much higher energy density. Besides, LIBs own the characteristics of no memory effect, high charging and discharging rate, long cycle life and high energy conversion rate. Therefore, LIBs have been widely considered as the most promising power source for mobile devices. Commonly used LIBs contain carbonate based liquid electrolytes. Such electrolytes own high ionic conductivity and excellent wetting ability. However, the use of highly flammable and volatile organic solvents in them may lead to problems like leakage, thermo runaway and parasitic interface reactions, which limit their application. Solid polymer electrolytes (SPEs) can solve these problems, while they also bring new challenges such as poor interfacial contact with electrodes and low ionic conductivity at room temperature. Many approaches have been tried to solve these problems. This article is divided into three parts to introduce polyethylene oxide (PEO) based polymer-ceramic hybrid solid electrolyte, which is one of the most efficient way to improve the performance of SPEs. The first part focuses on polymer-lithium salt (LiX) matrices, including their ionic conduction mechanism and impact factors for their ionic conductivity. In the second part, the influence of both active and passive ceramic fillers on SPEs are reviewed. In the third part, composite SPEs’ preparation methods, including solvent casting and thermocompression, are introduced and compared. Finally, we propose five key points on how to make composite SPEs with high ionic conductivity for reference.

An Improved Kernel Clustering Algorithm for Mixed-Type Data in Network Forensic

Min Ren,Peiyu Liu,Zhihao Wang,Lin Lü 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.1

Clustering algorithm is a common analysis technology for network forensics, which, lacking of any prior knowledge, can effectively find out the invasions by analyzing the collected real-time communication data flowing through the network. This paper proposed an improved dynamic kernel clustering algorithm for mixed numeric and categorical network communication data. First, centroid prototype based on the mean and distribution centroid was put forward to represent the cluster center. Then by using Gaussian kernel function, the paper introduced a new dissimilarity measure between the data object and the centroid prototype in combination with the significance of different categorical values. On this basis, the objective function was defined, which took into account both the compact degree in a cluster and the discrete degree among the clusters. After that an improved kernel clustering algorithm was designed. In the process of clustering, centroid prototype and the value of the clustering parameter dynamically updated for a better description of the characteristics of clusters’ change. Finally, in order to verify the feasibility and effectiveness of the algorithm, the paper further applied it to network forensics, and the experimental results showed that the method could mine the intrusion behavior more accurately.

Bioprocess Production of Sea Cucumber Rice Wine and Characterization of Functional Components and Antioxidant Activities

Shuai He,Lin Wang,Hao Dong,Pei Liu,Peiyu Shi,Xuemin Li,Xingchen Ren,Ning Lv,Yanan Liu,Changhu Xue,Hong Lin,Xiangzhao Mao 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.3

A new production bioprocess for sea cucumberrice wine (SCRW) was established. The traditional productiontechnology of Chinese rice wine was combined with additionof sea cucumber hydrosylates. The optimal enzymaticconditions of sea cucumber and the fermentation process ofSCRW were determined. The weight of sea cucumberenzymatic hydrolysates was 2.5% of millet while cookingthe millet. SCRW contained abundant free amino acids (30total at 1,681.216 mg/L), oligosaccharides (4 total at10,999.380 mg/L), total phenols (658.850 mg/L), andmineral elements (9 total at 1,911.353 mg/kg), and anantioxidant activity, all of which were higher than forcontrol rice wine (CRW). Galactosamine and glucuronicacid, both sea cucumber polysaccharides, were present inSCRW, but not in CRW.

Performance and sludge characteristics of anammox process at moderate and low temperatures

Jin Li,Dan Wang,Deshuang Yu,Peiyu Zhang 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.1

A sequencing batch reactor (SBR) was used to investigate the performance and sludge characteristics of anammox process at moderate and low temperatures. The initial pH was 7.5 and hydraulic retention time (HRT) was 3 h. When temperature was 25-35 oC, nitrogen removal rate (NRR) fluctuated from 1.67 to 1.82 kg/m3·d. However, when temperature dropped to 15 oC, NRR suddenly decreased by 0.48 kg/m3·d. Larger activation energy was acquired at lower temperature, and it was difficult to achieve efficient nitrogen removal under low temperature. When temperature declined to 10 oC, ΔNO2 −-N/ΔNH4 +-N and ΔNO3 −-N/ΔNH4 +-N reached 1.02 and 0.27, respectively. Inhibition resulting from low temperature on anammox activity was recoverable, and the modified Boltzmann model was appropriate to analyze recovery feature of anammox process. Low temperature not only led to poor nitrogen removal, but also affected sludge size and feature.