Transiting test method for galloping of iced conductor using wind generated by a moving vehicle

Pan Guo,Dongwei Wang,Shengli Li,Lulu Liu,Xidong Wang 한국풍공학회 2019 Wind and Structures, An International Journal (WAS Vol.28 No.3

This paper presents a novel test method for the galloping of iced conductor using wind generated by a moving vehicle which can produce relative wind field. The theoretical formula of transiting test is developed based on theoretical derivation and field test. The test devices of transiting test method for aerodynamic coefficient and galloping of an iced conductor are designed and assembled, respectively. The test method is then used to measure the aerodynamic coefficient and galloping of iced conductor which has been performed in the relevant literatures. Experimental results reveal that the theoretical formula of transiting test method for aerodynamic coefficient of iced conductor is accurate. Moreover, the driving wind speed measured by Pitot tube pressure sensors, as well as the lift and drag forces measured by dynamometer in the transiting test are stable and accurate. Vehicle vibration slightly influences the aerodynamic coefficients of the transiting test during driving in ideal conditions. Results of transiting test show that the tendencies of the aerodynamic coefficient curve are generally consistent with those of the wind tunnel tests in related studies. Meanwhile, the galloping is fairly consistent with that obtained through the wind tunnel test in the related literature. These studies validate the feasibility and effectiveness of the transiting test method. The present study on the transiting test method provides a novel testing method for research on the wind-resistance of iced conductor.

Environmentally Friendly Waterproof and Breathable Nanofiber Membranes with Thermal Regulation Performance by One-Step Electrospinning

Pan Zhang,Gaihuan Ren,Lulu Tian,Bo Li,Zhanzhao Li,Hongqin Yu,Rongwu Wang,Jianxin He 한국섬유공학회 2022 Fibers and polymers Vol.23 No.8

The waterproof and moisture permeable fabric with thermal regulation not only has the protective function forhuman body, but also meets the comfort of human clothing, which is a challenging and innovative research. Herein, we reportan environmentally friendly, simple, and high-efficiency strategy to fabricate waterproof and breathable nanofibermembranes with outstanding thermal regulation ability by introducing stearic acid (SA) into the hydrophobic siliceouspolyurethane (SIPU) solution by a facile one-step electrospinning. Owing to the addition of SA, the waterproofness of SIPU/SA nanofiber membranes is greatly improved, meanwhile, the addition of SA acted as a phase change material to imparttemperature regulation performance in appropriate temperature range to the SIPU/SA nanofiber membranes. By adjusting theaddition amount of the SA, eco-friendly and multifunctional SIPU/SA nanofiber membranes are systemically optimized withgood waterproofness (79 kPa), moisture breathability (8.0 kg m-2 d-1), and outstanding temperature regulation performance(latent heat up to 40 J/g), satisfied tensile strength (6.2 MPa) and excellent breaking elongation of 182 %. The obtained SIPU/SA nanofiber membranes can be suitable for the design of multifunctional wearable textiles for various applications,especially in outdoor protective clothing, medical clothing, intelligent clothing and military products.

Natural wind impact analysis of transiting test method to measure wind pressure coefficients

Shengli Li,Lulu Liu,Pan Guo,Xidong Wang 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.30 No.2

Building wind pressure coefficient transiting test is a new method to test the building wind pressure coefficient by using the wind generated by a moving vehicle, which is susceptible to natural wind and other factors. In this paper, the Commonwealth Advisory Aeronautical Research Council standard model with a scale ratio of 1:300 is used as the test object, and the wind pressure coefficient transiting test is repeated under different natural wind conditions to study the influence of natural wind. Natural wind is measured by an ultrasonic anemometer at a fixed location. All building wind pressure coefficient transiting tests meet the test conditions, and the vehicle’s driving speed is 72 km/h. The mean wind pressure coefficient, the fluctuating wind pressure coefficient, and the correlation coefficient of wind pressure are used to describe the influence of natural wind on the building wind pressure coefficient transiting test qualitatively and quantitatively. Some rules, which can also help subsequent transiting tests, are also summarized.

Schisandrin A ameliorates MPTP‑induced Parkinson’s disease in a mouse model via regulation of brain autophagy

Yinghao Zhi,Yongxi Jin,Lulu Pan,Aiguo Zhang 대한약학회 2019 Archives of Pharmacal Research Vol.42 No.11

Schisandrin A (Sch A) is one of the principalbioactive lignans isolated from Fructus schisandrae. In thisstudy, we demonstrated its protective effect and biochemicalmechanism of action in a 1-methyl-4-phenyl-1, 2, 3,6-tetrahydropyridine-induced mouse model of Parkinson’sdisease. Sch A significantly ameliorated behavioural abnormalitiesand increased the number of nigral dopaminergicneurons detected by tyrosine hydroxylase immunohistochemistry. Pre-treatment with Sch A significantly decreasedthe levels of the inflammatory mediators IL-6, IL-1β, andTNF-α and markedly improved antioxidant defences byinhibiting the activity of MDA and increasing that of SOD. Furthermore, Sch A activated expression of the autophagyrelatedproteins LC3-II, beclin1, parkin, and PINK1 andincreased mTOR expression. Taken together, these findingsindicate that Sch A has neuroprotective effects against thedevelopment of Parkinson’s disease via regulation of brainautophagy.

Effect of welding residual stress on operating stress of nuclear turbine low pressure rotor

Tan Long,Zhao Liangyin,Zhao Pengcheng,Wang Lulu,Pan Jiajing,Zhao Xiuxiu 한국원자력학회 2020 Nuclear Engineering and Technology Vol.52 No.8

The purpose of this study is to investigate the effect of welding residual stress on operating stress in designing a nuclear turbine welded rotor. A two-dimensional axisymmetric finite element model is employed to calculate the residual stress before and after post weld heat treatment (PWHT), and then the superposition of residual stress after PWHT and operating stress at normal speed and overspeed were discussed. The investigated results show that operating stress can be affected significantly by welding residual stress, and the distribution trend of superposition stress at the weld area is mainly determined by welding residual stress. The superposition of residual stress and operating stress is linear superposition, and the hoop stress distribution of superposition stress is similar with the distribution of residual stress. With the increasing overspeed, the distribution pattern of the hoop superimposed stress remains almost unchanged, while the stress level increases

BK Knockout by TALEN-Mediated Gene Targeting in Osteoblasts: KCNMA1 Determines the Proliferation and Differentiation of Osteoblasts

Hei, Hongya,Gao, Jianjun,Dong, Jibin,Tao, Jie,Tian, Lulu,Pan, Wanma,Wang, Hongyu,Zhang, Xuemei Korean Society for Molecular and Cellular Biology 2016 Molecules and cells Vol.39 No.7

Large conductance calcium-activated potassium (BK) channels participate in many important physiological functions in excitable tissues such as neurons, cardiac and smooth muscles, whereas the knowledge of BK channels in bone tissues and osteoblasts remains elusive. To investigate the role of BK channels in osteoblasts, we used transcription activator-like effector nuclease (TALEN) to establish a BK knockout cell line on rat ROS17/2.8 osteoblast, and detected the proliferation and mineralization of the BK-knockout cells. Our study found that the BKknockout cells significantly decreased the ability of proliferation and mineralization as osteoblasts, compared to the wild type cells. The overall expression of osteoblast differentiation marker genes in the BK-knockout cells was significantly lower than that in wild type osteoblast cells. The BK-knockout osteoblast cell line in our study displays a phenotype decrease in osteoblast function which can mimic the pathological state of osteoblast and thus provide a working cell line as a tool for study of osteoblast function and bone related diseases.

BK Knockout by TALEN-Mediated Gene Targeting in Osteoblasts: KCNMA1 Determines the Proliferation and Differentiation of Osteoblasts

Xuemei Zhang,Hongya Hei,Jianjun Gao,Jibin Dong,Jie Tao,Lulu Tian,Wanma Pan,Hongyu Wang 한국분자세포생물학회 2016 Molecules and cells Vol.39 No.7

Large conductance calcium-activated potassium (BK) channels participate in many important physiological functions in excitable tissues such as neurons, cardiac and smooth muscles, whereas the knowledge of BK channels in bone tissues and osteoblasts remains elusive. To investigate the role of BK channels in osteoblasts, we used transcription activator-like effector nuclease (TALEN) to establish a BK knockout cell line on rat ROS17/2.8 osteoblast, and detected the proliferation and mineralization of the BK-knockout cells. Our study found that the BK-knockout cells significantly decreased the ability of proliferation and mineralization as osteoblasts, compared to the wild type cells. The overall expression of osteoblast differentiation marker genes in the BK-knockout cells was significantly lower than that in wild type osteoblast cells. The BK-knockout osteoblast cell line in our study displays a phenotype decrease in osteoblast function which can mimic the pathological state of osteoblast and thus provide a working cell line as a tool for study of osteoblast function and bone related diseases.