Effect of Halloysite Clay on Magnetic Carbonyl Iron-Based Magnetorheological Fluid

Cheng Hai Hong,Hyoung Jin Choi IEEE 2014 IEEE transactions on magnetics Vol.50 No.11

<P>Soft magnetic carbonyl iron (CI)-based magnetorheological (MR) fluids with different loadings of halloysite nanoclay were prepared, in which the MR fluid is a complex colloidal suspension consisting of magnetic particles dispersed in a liquid, showing its rapid, reversible, and tunable change between a liquid-like and solid-like state with an applied external magnetic field. The MR characteristics were measured via rotational tests, in which the flow curves exhibited a non-Newtonian behavior for all investigated samples under applied magnetic fields. Flow curves showed not only the dynamic yield stress change measured as a function of magnetic field strength using a power law fit, but also the existence of a solid-like character. Sedimentation of the MR fluid with and without an additive was also examined.</P>

Ultimate behavior of long-span steel arch bridges

Cheng, Jin,Jiang, Jian-Jing,Xiao, Ru-Cheng,Xiang, Hai-Fan Techno-Press 2002 Structural Engineering and Mechanics, An Int'l Jou Vol.14 No.3

Because of the increasing span of arch bridges, ultimate capacity analysis recently becomes more focused both on design and construction. This paper investigates the static and ultimate behavior of a long-span steel arch bridge up to failure and evaluates the overall safety of the bridge. The example bridge is a long-span steel arch bridge with a 550 m-long central span under construction in Shanghai, China. This will be the longest central span of any arch bridge in the world. Ultimate behavior of the example bridge is investigated using three methods. Comparisons of the accuracy and reliability of the three methods are given. The effects of material nonlinearity of individual bridge element and distribution pattern of live load and initial lateral deflection of main arch ribs as well as yield stresses of material and changes of temperature on the ultimate load-carrying capacity of the bridge have been studied. The results show that the distribution pattern of live load and yield stresses of material have important effects on bridge behavior. The critical load analyses based on the linear buckling method and geometrically nonlinear buckling method considerably overestimate the load-carrying capacity of the bridge. The ultimate load-carrying capacity analysis and overall safety evaluation of a long-span steel arch bridge should be based on the geometrically and materially nonlinear buckling method. Finally, the in-plane failure mechanism of long-span steel arch bridges is explained by tracing the spread of plastic zones.

Status of Exclusive Baryonic B Decays

Hai-Yang Cheng 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.2

The status of exclusive two-body and three-body baryonic B decays is reviewed. The threshold peaking effect in baryon pair invariant mass is stressed and explained. Weak radiative baryonic B decays mediated by the electromagnetic penguin process are discussed.

Development and Characterization of a Novel Anti-idiotypic Monoclonal Antibody to Growth Hormone, Which Can Mimic Physiological Functions of Growth Hormone in Primary Porcine Hepatocytes

Hai-Nan Lan,Hai-Long Jiang,Wei Li,Tian-Cheng Wu,Pan Hong,Yu Meng Li,Hui Zhang,Huan-Zhong Cui,Xin Zheng 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.4

B-32 is one of a panel of monoclonal anti-idiotypic antibodies to growth hormone (GH) that we developed. To characterize and identify its potential role as a novel growth hormone receptor (GHR) agonist, we determined that B-32 behaved as a typical Ab2β based on a series of enzyme-linked immunosorbent assay assays. The results of fluorescence-activated cell sorting, indirect immunofluorescence and competitive receptor binding assays demonstrated that B-32 specifically binds to the GHR expressed on target cells. Next, we examined the resulting signal transduction pathways triggered by this antibody in primary porcine hepatocytes. We found that B-32 can activate the GHR and Janus kinase (2)/signal transducers and activators of transcription (JAK2/STAT5) signalling pathways. The phosphorylation kinetics of JAK2/STAT5 induced by either GH or B-32 were analysed in dose-response and time course experiments. In addition, B32 could also stimulate porcine hepatocytes to secrete insulin-like growth factors-1. Our work indicates that a monoclonal anti-idiotypic antibody to GH (B-32) can serve as a GHR agonist or GH mimic and has application potential in domestic animal (pig) production.

Electric and magnetic field-responsive suspension rheology of core/shell-shaped iron oxide/polyindole microspheres

Cheng Hai Hong,장효선,오석준,Fu Li-hai,최형진 한국유변학회 2023 Korea-Australia rheology journal Vol.35 No.2

In this study, conductive polyindole (PIn) was coated onto initially fabricated magnetic iron oxide ( Fe3O4) particles via chemical oxidative polymerization, and the synthesized core–shell structured hybrid smart particles were used as smart electrorheological/magnetorheological (EMR) materials. The synthesized Fe3O4/ PIn particles were characterized using scanning electron microscopy and transmission electron microscopy. In addition, the chemical composition of the synthesized particles was confirmed using Fourier-transform infrared spectroscopy. Their magnetic properties were further analyzed using VSM. Consequently, the Fe3O4/ PIn particle-based suspension, which was both magnetic and conductive, was found to exhibit interesting dual stimuli under both external electric and magnetic fields. Various rheological measurements, including shear simple steady shear and dynamic tests, were employed to evaluate the behavior of typical EMR suspensions. Furthermore, the dielectric properties of the particles were analyzed using an LCR meter. Based on the dielectric spectrum data, the relaxation time (λ) was estimated to be 1.5 × 10– 8 s at the maximum frequency (λ = 1/2πfmax). Measurements conducted using a Turbiscan indicated enhanced sedimentation stability of the particles owing to a decrease in the particle density from 4.34 to 2.93 g/cm3.

Automatic Image Segmentation with PCNN Algorithm Based on Grayscale Correlation

Hai-Rong Ma,Xin-Wen Cheng 보안공학연구지원센터 2014 International Journal of Signal Processing, Image Vol.7 No.5

In order to use pulse coupled neural networks (PCNN) for precise automatic image segmentation, we propose an improved PCNN model. We first establish a connection weight matrix based on the image local gray correlation and on the Euclid distance. We then used the minimum variance ratio criterion to automatically determine PCNN cycle times, and achieve automatic image segmentation. The simulation results show that this method can automatically determine the number of iterations PCNN, and that it is highly feasible and better segmentation effect.

Rotating disk apparatus for polymer-induced turbulent drag reduction

Cheng Hai Hong,최형진,김재호 대한기계학회 2008 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.22 No.10

In order to investigate turbulent drag reduction (DR), a rotating disk apparatus (RDA) generating an “external flow” was designed and then polymer-induced DR efficiency of water-soluble polymers both poly (ethylene oxide) (PEO) and poly (acryl amide) (PAAM) were examined as a function of either polymer concentration or temperature. The need for a sensitive measuring system at high Reynolds numbers has stimulated the development of a high-precision computer- aided system, which is able to measure the difference between the torques for a Newtonian fluid and a dilute polymeric solution with drag reducers very accurately. Their mechanical degradation behavior in the RDA as a function of time in a turbulent flow was also analyzed using both a simple exponential decay function and a fractional exponential decay equation. The fractional exponential decay equation was found to fit the experimental data better than the simple first-order degradation exponential decay function in the case of PEO.

Plant.Green.Living Environment -Urban Construction and Establishment of Green Space in Kunming-

Cheng, Hai-Lan The Korean Institute of Landscape Architecture 2001 Journal of the Korean institute of landscape archi Vol.1 No.-

Green and plants, as it symbol the life and depute the nature, always give human an easy comfort psychologically. The paper is a brief analysis to the idea frame of urban construction and reform of Kunming through our practice about ten years. On which three main principles should be carefully considered. One is that the green-space composed of plant system is of the important infrastructure of a modern city as it can not be instead of by any other factor in the ecological system of the city. The other is that in the course of planning and construction the local feature as well as its culture tradition in history should be pied more attention. In order to create a distinguish character of itself the third may be more important that to coordinate each key elements of it such as green, water, light, building, road, etc., to get a harmonious sphere of human and nature. A modern city should be a green city in which nature and man co-exist harmoniously.

Shear stress analysis of phosphorylated potato starch based electrorheological fluid

Hong, Cheng-Hai,Choi, Hyoung-Jin The Korean Society of Rheology 2007 Korea-Australia rheology journal Vol.19 No.4

Electrorheological characteristics of a dispersed system of phosphorylated potato starch particles in silicone oil investigated via a rotational rheometer equipped with a high voltage generator is being reanalysized. Flow curves of these ER fluids both under several applied electric field strengths and with different degrees of phosphate substitution were mainly examined via three different rheological constitutive equations of Bingham model, De Kee-Turcotte model and our previously proposed CCJ model. Among these, the CCJ equation was found to fit the data of phosphorylated potato starch well.

Hydraulic fracturing experiments of highly deviated well with oriented perforation technique

Zhu, Hai Y.,Deng, Jin G.,Liu, Shu J.,Wen, Min,Peng, Cheng Y.,Li, Ji R.,Chen, Zi J.,Hu, Lian B.,Lin, Hai,Guang, Dong Techno-Press 2014 Geomechanics & engineering Vol.6 No.2

In order to investigate the effect of different perforation angles (the angle between the perforation direction and the maximum horizontal principal stress) on the fracture initiation and propagation during hydraulic fracturing of highly deviated well in oil & gas saturated formation, laboratory experiments of the hydraulic fracturing had been carried out on the basis of non-dimensional similar criteria by using 400^3 $mm^3$ cement cubes. A plane fracture can be produced when the perforations are placed in the direction of the maximum horizontal principal stress. When the perforation angle is $45^{\circ}$, the fractures firstly initiate from the perforations at the upper side of the wellbore, and then turn to the maximum horizontal principal stress direction. When the well deviation angle and perforation angle are both between $45^{\circ}$ and $90^{\circ}$, the fractures hardly initiate from the perforations at the lower side of the wellbore. Well azimuth (the angle between the wellbore axis and the maximum horizontal principal stress) has a little influence on the fracture geometries; however it mainly increases the fracture roughness, fracture continuity and the number of secondary fractures, and also increases the fracture initiation and propagation pressure. Oriented perforating technology should be applied in highly deviated well to obtain a single plane fracture. If the well deviation angle is smaller, the fractures may link up.