Beam-target configurations and robustness performance of the tungsten granular flow spallation target for an Accelerator-Driven Sub-critical system

Cai Han-Jie,Jia Huan,Qi Xin,Lin Ping,Zhang Sheng,Tian Yuan,Qin Yuanshuai,Zhang Xunchao,Yang Lei,He Yuan 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.7

The dense granular flow spallation target is a new target concept proposed for an Accelerator-Driven Sub-critical (ADS) system. In this paper, the beam-target configurations of a tungsten granular flow target for the ADS with a thermal power of 1 GW is explored. The beam profile options using different scanning methods are discussed. The critical geometry parameters are adjusted to investigate the performance of the granular target from the aspects of neutron efficiency, stability and temperature distribution in target medium. To figure out how the target under accident conditions would behave, different clogging conditions are induced in the simulation. The dynamic processes are analyzed and some important parameters such as abnormal temperature rise and beam cutoff time window are obtained. The response of the sub-critical reactor to a clogging accident is also investigated. It is indicated that the monitoring of the granular flow by the neutron detectors in the sub-critical core will be effective

Targeting SHCBP1 Inhibits Cell Proliferation in Human Hepatocellular Carcinoma Cells

Tao, Han-Chuan,Wang, Hai-Xiao,Dai, Min,Gu, Cheng-Yu,Wang, Qun,Han, Ze-Guang,Cai, Bing Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Src homology 2 domain containing (SHC) is a proto-oncogene which mediates cell proliferation and carcinogenesis in human carcinomas. Here, the SHC SH2-domain binding protein 1 (SHCBP1) was first established to be up-regulated in human hepatocellular carcinoma (HCC) tissues by array-base comparative genome hybridization (aCGH). Meanwhile, we examine and verify it by quantitative real-time PCR and western blot. Our current data show that SHCBP1 was up-regulated in HCC tissues. Overexpression of SHCBP1 could significantly promote HCC cell proliferation, survival and colony formation in HCC cell lines. Furthermore, knockdown of SHCBP1 induced cell cycle delay and suppressed cell proliferation. Furthermore, SHCBP1 could regulate the expression of activate extracellular signal-regulated kinase 1/2 (ERK1/2) and cyclin D1. Together, our findings indicate that SHCBP1 may contribute to human hepatocellular carcinoma by promoting cell proliferation and may serve as a molecular target of cancer therapy.

Zero-watermarking Algorithm for Medical Volume Data Based on Legendre Chaotic Neural Network and Perceptual Hashing

Baoru Han,Lisha Cai,Wenfeng Li 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.1

Medical information digitization makes the medical information storage and extraction more convenient. Medical image information security and copyright protection is also gradually being taken seriously, and some medical image watermarking has been applied. According to the characteristics of three-dimensional medical images, this paper proposes a robust zero-watermarking algorithm for medical volume data based on legendre chaotic neural network and perceptual hashing. The algorithm is based on three-dimensional discrete wavelet transform frequency analysis features, which uses perceptual hashing technique to extract medical volume data itself feature vector in order to structure robust zero watermarking. And using legendre chaotic neural network to generate chaotic sequence to enhance the security of the watermarking. The algorithm achieves a combination of legendre chaotic neural network encryption and zero-watermarking technology, which can improve the medical volume data watermarking algorithm security and robustness. The simulation results show the effectiveness of the algorithm.

THEORETICAL ANALYSIS AND EXPERIMENT STUDY ON FLOW BETWEEN PARALLEL ROUGH PLATES

De Cai Han,Dao Hang Sha,Yi Qun Wang 대한기계학회 1992 International Conference on Fluid Machinery Vol.1 No.1

Modification of ion permeability utilizing pH-dependent selective swelling of polyelectrolyte multilayer films.

Cai, Gangri,Lee, Wonjoo,Min, Sun-Ki,Koo, Gumae,Cho, Byung Won,Lee, Soo-Hyoung,Han, Sung-Hwan American Scientific Publishers 2009 Journal of Nanoscience and Nanotechnology Vol.9 No.12

<P>The selective swelling behavior of polyelectrolyte multilayer (PEM) films prepared by layer-by-layer (L-b-L) assembly influences the ion-permeability in contrast to surface charge density of the films. The cation terminated polyethylene amine (PEI) and anion terminated polyacrylic acid (PAA) were dissolved in DI water, and the pH was adjusted to 10 and 4, respectively, exemplifies thick denser film with good layering structure. The layered polyelectrolyte films has selective swelling behavior at pH 4 (PEI) or pH 10 (PAA), influences the permeability of both Ru(NH3)6(2+) and Fe(CN)6(3-) rather than surface charge character or film charge density. The swollen top most layer shows 'on' character, whereas, shrunken top most layer shows 'off' character for the ion-permeability. Such 'on-off' character can be used for the pH-dependent switches based on surface morphology.</P>

Experimental and numerical studies of aerodynamic forces on vehicles and bridges

Han, Yan,Hu, Jiexuan,Cai, C.S.,Chen, Zhengqing,Li, Chunguang Techno-Press 2013 Wind and Structures, An International Journal (WAS Vol.17 No.2

An accurate identification of the aerodynamic characteristics of vehicles and the bridge is the premise for the coupled vibration analysis of a wind-vehicle-bridge system. At present, the interaction of aerodynamic forces between the road vehicles and bridge is ignored in most previous studies. In the present study, an experimental setup was developed to measure the aerodynamic characteristics of vehicles and the bridge for different cases in a wind tunnel considering the aerodynamic interference. The influence of the wind turbulence, the wind speed, the vehicle interference, and the vehicle position on the aerodynamic coefficients of vehicles, and the influence of vehicles on the static coefficients of the bridge were investigated, based on the experimental results. The variations in the aerodynamic characteristics of vehicles and the bridge were studied and the measured results were validated according to the results of surface pressure measurements on the vehicle and the bridge. The measured results were further validated by comparing the measured results with values derived numerically. The measured results showed that the wind turbulence, the vehicle interference, and the vehicle position significantly affected the aerodynamic coefficients of vehicles. However, the influence of the wind speed on the aerodynamic coefficients of the studied vehicle is small. The static coefficients of the bridge were also significantly influenced by the presence of vehicles.

Wnt5a plays a crucial role in determining tooth size during murine tooth development.

Cai, Jinglei,Mutoh, Noriko,Shin, Jeong-Oh,Tani-Ishii, Nobuyuki,Ohshima, Hayato,Cho, Sung-Won,Jung, Han-Sung Springer 2011 Cell and tissue research Vol.345 No.3

<P>We have previously demonstrated that tooth size is determined by dental mesenchymal factors. Exogenous bone morphogenetic protein (BMP)4, Noggin, fibroblast growth factor (FGF)3 and FGF10 have no effect on tooth size, despite the expressions of Bmp2, Bmp4, Fgf3, Fgf10 and Lef1 in the dental mesenchyme. Among the wingless (Wnt) genes that are differentially expressed during tooth development, only Wnt5a is expressed in the dental mesenchyme. The aims of the present study were to clarify the expression pattern of Wnt5a in developing tooth germs and the role of Wnt5a in the regulation of tooth size by treatment with exogenous WNT5A with/without an apoptosis inhibitor on in vitro tooth germs combined with transplantation into kidney capsules. Wnt5a was intensely expressed in both the dental epithelium and mesenchyme during embryonic days 14-17, overlapping partly with the expressions of both Shh and Bmp4. Moreover, WNT5A retarded the development of tooth germs by markedly inducing cell death in the non-dental epithelium and mesenchyme but not widely in the dental region, where the epithelial-mesenchymal gene interactions among Wnt5a, Fgf10, Bmp4 and Shh might partly rescue the cells from death in the WNT5A-treated tooth germ. Together, these results indicate that WNT5A-induced cell death inhibited the overall development of the tooth germ, resulting in smaller teeth with blunter cusps after tooth-germ transplantation. Thus, it is suggested that Wnt5a is involved in regulating cell death in non-dental regions, while in the dental region it acts as a regulator of other genes that rescue tooth germs from cell death.</P>

Flutter stability of a long-span suspension bridge during erection

Han, Yan,Liu, Shuqian,Cai, C.S.,Li, Chunguang Techno-Press 2015 Wind and Structures, An International Journal (WAS Vol.21 No.1

The flutter stability of long-span suspension bridges during erection can be more problematic and more susceptible to be influenced by many factors than in the final state. As described in this paper, numerical flutter stability analyses were performed for the construction process of Zhongdu Bridge over Yangtze River using the commercial FE package ANSYS. The effect of the initial wind attack angle, the sequence of deck erection, the stiffness reduction of stiffening girders, the structural damping, and the cross cables are discussed in detail. It was found that the non-symmetrical sequence of deck erection was confirmed to be aerodynamically favourable for the deck erection of long-span suspension bridges and the best erection sequence should be investigated in the design phase. While the initial wind attack angle of $-3^{\circ}$ is advantageous for the aerodynamic stability, $+3^{\circ}$ is disadvantageous compared with the initial wind attack angle of $0^{\circ}$ during the deck erection. The stiffness reduction of the stiffening girders has a slight effect on the flutter wind speed of the suspension bridge during erection, but structural damping has a great impact on it, especially for the early erection stages.

Patterning the size and number of tooth and its cusps

Cai, Jinglei,Cho, Sung-Won,Kim, Jae-Young,Lee, Min-Jung,Cha, Yoon-Geun,Jung, Han-Sung Elsevier 2007 Developmental Biology Vol.304 No.2

<P><B>Abstract</B></P><P>Mice and rats, two species of rodents, show some dental similarities such as tooth number and cusp number, and differences such as tooth size and cusp size. In this study, the tooth size, tooth number, cusp size and cusp number, which are four major factors of the tooth patterning, were investigated by the heterospecific recombinations of tissues from the molar tooth germs of mice and rats. Our results suggest that the dental epithelium and mesenchyme determine the cusp size and tooth size respectively and the cusp number is co-regulated by the tooth size and cusp size. It is also suggested that the mesenchymal cell number regulates not the tooth size but the tooth number. The relationships among these factors in tooth patterning including micropatterning (cusp size and cusp number) and macropatterning (tooth size and tooth number) were analyzed in a reaction diffusion mechanism. Key molecules determining the patterning of teeth remains to be elucidated for controlling the tooth size and cusp size of bioengineered tooth.</P>

Correlation Between Tunable Oxygen Defects in TiO2 Nanoflower and its Photocatalytic Performance for the Degradation of Organic Waste

Cai Chen,Han Zhang,Arshid M. Ali,Hui Zhang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2020 NANO Vol.15 No.03

Oxygen defects of nanoflower TiO2 photo-catalyst was fabricated at the presence of hydrogen at different temperatures (100–600℃) and the concentrations of oxygen defects were firstly quantitatively analyzed by hydrogen programmed temperature reduction techniques (H2-TPR). Total oxygen defect concentration and surface oxygen defect concentration were consistent with XPS and EPR results, respectively. Even at the hydrogen thermal temperature of 600 ℃, the shape of TiO2 was still kept as nanoflower structure as characterized by SEM. However, the rutile and anatase coexist in the composition of crystal phase when hydrogen reduction temperature of the TiO2 catalyst reached 400 ℃ to 600 ℃ as proved by Raman and XRD results. TiO2 sample with oxygen defects shows excellent photo-catalytic activity for degradation of Direct Blue 78 (DB) regardless of ultraviolet light (the maximum degradation rate achieved within 100 min was 93.27%) or visible light (the maximum degradation rate achieved within 100 min was 88.25%). The photo-catalytic activity seems to be highly correlated with the surface oxygen defects of TiO2 catalyst. With surface oxygen-defect concentrations increase, the degradation ability on DB was significantly enhanced, while bulk oxygen defects had negligible effect on the photo-catalytic activity. The enhanced photo-catalytic performance of TiO2 with a fixed amount of oxygen defects was attributed to the strong capturing capability of the photo-generated electrons. In addition, the surface defects could also improve the photo-catalytic reaction efficiency.