SYNTHESIS AND FIELD EMISSION PROPERTIES OF SnS_2 AND In-DOPED SnS_2 WITH HIERARCHICAL STRUCTURE

H. X. ZHONG,C. X. WANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2011 NANO Vol.6 No.5

A simple hydrothermal route was employed to prepare flower-like SnS_2 and In-doped SnS_2 by using biomolecular L-cysteine as sulfur source. The synthetic samples were characterized by X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy in detail. Furthermore, the field emission from both the materials was investigated, it was found that both of them have excellent field emission properties, and the doped In has enhanced the field emission properties.

Spectral tomographic analysis of Bremsstrahlung X-rays generated in a laser-produced plasma

Rhee, Y.J.,Nam, S.M.,Peebles, J.,Sawada, H.,Wei, M.,Vaisseau, X.,Sasaki, T.,Giuffrida, L.,Hulin, S.,Vauzour, B.,Santos, J.J.,Batani, D.,McLean, H.S.,Patel, P.K.,Li, Y.T.,Yuan, D.W.,Zhang, K.,Zhong, J. Cambridge University Press 2016 Laser and particle beams Vol.34 No.4

<B>Abstract</B><P>A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.</P>

Clarifying the basic phase structure and magnetic behavior of directly quenched (Ce,La)2Fe14B alloys with various Ce/La ratios

X.F. Liao,L.Z. Zhao,J.S. Zhang,G. Ahmed,A.J. Khan,H.X. Zeng,H.Y. Yu,X.C. Zhong,Z.W. Liu,G.Q. Zhang 한국물리학회 2019 Current Applied Physics Vol.19 No.6

To improve the performance/cost ratio of NdFeB based permanent magnets, Ce or/and La substitutions for Nd have been suggested. To better understand the effects of these substitutions, the fundamental behavior of (Ce,La)-Fe-B alloys has to be clearly understood. Here, we reported a systematic investigation on the phase structure, microstructure, and magnetic properties of melt-spun (Ce,La)2Fe14B alloys. The results confirm that partial substitution of Ce by La can effectively enhance the hard magnetism and thermal stability of (Ce1- xLax)2Fe14B alloys, while over 80% La substitution leads to the decomposition of 2:14:1 phase. The lattice parameters a, c and the Curie temperature Tc of 2:14:1 phase increase linearly with the increasing La content. La substitution can effectively refine the grain, resulting in the enhancement of inter-grain exchange coupling. The (Ce0.7La0.3)2Fe14B alloy with a mean grain size of 25 nm exhibits high remanence, maximum energy product and intrinsic coercivity up to 0.69 T, 6.2 MGOe and 217 kA/m, respectively. The present work provides a good understanding on the melt-spun (Ce,La)-Fe-B system for further developing low cost rare earth permanent magnets.

Measurement of the Secondary Neutron Emission Differential and Double-Differential Cross Sections between 20 and 30 MeV

X. C. Ruan,G. C. Chen,H. X. Huang,X. Li,Y. B. Nie,B. Zhou,Z. Y. Ma,J. Bao,Q. P. Zhong,Z. Y. Zhou,H. Q. Tang,J. S. Zhang,C. L. Lan,Y. L. Zhang,Y. M. Li 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.23

More and more interests have been paid to the differential and double-differential neutron emission cross sections (DX and DDX) at above 20 MeV region in recent years. At the China Institute of Atomic Energy (CIAE), a program to measure the DX and DDX between 20 and 30 MeV neutron energy region has been carried out. The d-T reaction neutron source was used to produce the 20 - 30 MeV neutrons with a tritium gas target at the HI-13 tandem accelerator at CIAE. The time-of-flight(TOF) technique was used to measure the neutron energy from about 1 MeV to 30 MeV with 3 BC501A liquid scintillators (with a size of Φ180 ×100 mm). A preliminary measurement has been carried out for ^9Be at 22 MeV. The measured data were analyzed by detailed Monte-Carlo simulation to perform the multiple scattering, flux attenuation and finite geometry corrections. The experimental details, the data analysis, the progress, the results and the future plan will be presented in this report.

Growth Performance, Carcass Composition and Meat Quality of Jiulong-yak (Bos grunniens)

Zi, X.D.,Zhong, G.H.,Wen, Y.L.,Zhong, J.C.,Liu, C.L.,Ni, Y.A.,Yezi, Y.H.,Ashi, M.G. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.3

Estimated liveweights, carcass characteristics, the proximate composition and amino-acid composition of the whole rib cut of the 10th/12th thoracic vertebrae have been determined for Jiulong-yak. The animal grows rapidly up to puberty at 2-3 years of age. At those ages, females reached 143.0$\pm$34.7 kg and 184.0$\pm$30.8 kg (SD) respectively, which was 60 to 80% of their mature weight at 6 to 7 yr old, then the rate of growth significantly slowed down. Males continued to rapidly increase body weight until an older age possibly due to the selection procedures. Animals included 20 males aged from 2.5 to 6.5 yr, seven females aged of 4.5 yr and 11 steers aged of 4.5-5.5 yr were slaughtered for carcass determination and chemical analysis of meat samples. Dressing-out percentage and ribeye area ranged from 48.53-55.04% and 48.02-68.56 $cm^2$ respectively, both of which differed by age and sex. Yak meat is scarlet in color and intramuscular marbling is poor. The 10th/12th rib-cut contained 24.99-31.93% dry matter; 19.98-22.58% protein; 2.52-10.86% fat and 0.93-1.00% ash. Meat from females and steers contained a higher percentage of fat than those from bulls. The pH of M. Longissimus dorsi measured at 24 h post-mortem ranged from 5.84-6.11. Amino acid composition was similar to that for other red meat, except for a lower content of methionine (1.26 g/100 g meat). The results indicated that yak meat can make a valuable contribution to the diets for the highlanders.

Effects of Graded Levels of Isomaltooligosaccharides on the Performance, Immune Function and Intestinal Status of Weaned Pigs

Wang, X.X.,Song, P.X.,Wu, H.,Xue, J.X.,Zhong, X.,Zhang, L.Y. Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.2

The objective of this study was to investigate the effects of graded levels of isomaltooligosaccharides (IMO) on the performance, immune function and intestinal microflora and intestinal mucosal morphology of weaned pigs. In a 28-day experiment, one hundred eighty, twenty eight-day-old, crossbred (Duroc${\times}$Large White${\times}$Landrace), weaned pigs, with an initial body weight of $8.19{\pm}1.45kg$, were fed either an unsupplemented corn-soybean meal based diet or similar diets supplemented with 0.2%, 0.4%, 0.6%, or 0.8% IMO added at the expense of corn. Each treatment was replicated six times with six pigs (three barrows and three gilts) per pen. From day 0 to 14, weight gain was linearly increased (p<0.05), while gain:feed (p<0.05) was linearly improved and diarrhea rate (p = 0.05) linearly declined as the IMO level increased. On d 14, the level of the immunoglobulins IgA, IgM, and IgG in the serum of pigs were linearly increased (p<0.05) with increasing IMO supplementation. Interleukin-6 (IL-6) was linearly (p<0.05) and quadratically (p<0.05) decreased as IMO intake increased. From day 15 to 28, there was a trend for weight gain to be linearly increased, and IL-2 was linearly (p<0.05) increased as IMO supplementation increased on d 28. Over the entire experiment, weight gain was linearly increased (p<0.05), while gain:feed (p<0.05) was linearly improved and diarrhea rate (p<0.05) was linearly decreased as the IMO level increased. Supplementation with IMO had no effect on the intestinal microflora of pigs in the ileum and cecum of pigs, as well as the villus height and crypt depth in the ileum and jejunum (p>0.05). These results indicate that dietary inclusion of IMO increases weight gain, gain:feed and enhanced the immune status of pigs, and could be a valuable feed additive for use in weaned pigs, particularly during the period immediately after weaning.

100KW DC Arc Plasma of CVD System for Low Cost Large Area Diamond Film Deposition

Lu, F.X.,Zhong, G.F.,Fu, Y.L.,Wang, J.J.,Tang, W.Z.,Li, G.H.,Lo, T.L.,Zhang, Y.G.,Zang, J.M.,Pan, C.H.,Tang, C.X.,Lu, Y.P. The Korean Ceramic Society 1996 The Korean journal of ceramics Vol.2 No.4

In the present paper, a new type of DC arc plasma torch is disclosed. The principles of the new magnetic and fluid dynamic controlled large orifice long discharge tunnel plasma torch is discussed. Two series of DC Plasma Jet diamond film deposition equipment have been developed. The 20kW Jet equipped with a $\Phi$70 mm orifice torch is capable of deposition diamond films at a growth rate as high as 40$\mu\textrm{m}$/h over a substrate area of $\Phi$65 mm. The 100kW high power Jet which is newly developed based on the experience of the low power model is equipped with a $\Phi$120 mm orifice torch, and is capable of depositing diamond films over a substrate area of $\Phi$110 mm at growth rate as high as 40 $\mu\textrm{m}$/h, and can be operated at gas recycling mode, which allows 95% of the gases be recycled. It is demonstrated that the new type DC plasma torch can be easily scaled up to even higher power Jet. It is estimated that even by the 100kW Jet, the cost for tool grade diamond films can be as low as less than $4/carat.

Tensile and Creep Deformation of a Newly Developed Ni-Fe-Based Superalloy for 700 °C Advanced Ultra-Supercritical Boiler Applications

Y. Yuan,Z. H. Zhong,Z.S. Yu,H. F. Yin,Y. Y. Dang,X. B. Zhao,Z. Yang,J. T. Lu,J. B. Yan,Y. Gu 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.4

A new Ni-Fe-based superalloy, HT-X, has been developed for applications in 700 °C advanced ultra-supercritical (A-USC) boilers. The HT-X alloy is subjected to various heat treatments. Tensile tests are conducted at room temperature (RT), 700 °C and 750 °C. Creep tests are carried out under conditions of 700 °C/300 MPa and 750 °C/150 MPa. After aging treatment, the yield strength of the HT-X alloy at RT and 750 °C is 787 MPa and 624 MPa, respectively. When additional thermal exposure at 750 °C for 5400 h is applied, the yield strength is decreased to 656 MPa at RT and 480 MPa at 700 °C. For an aged specimen, the a/2<110> dislocation shearing process occurs when tensile testing is conducted at RT and 750 °C. As the γ' precipitate size increases in the specimen that is thermally exposed at 750 °C for 5400 h, Orowan bowing is the dominant dislocation process, and stacking faults develop in the γ' precipitates at both RT and 700 °C. Dislocation slip combined with climb is the dominant mechanism under the creep testing conditions. The factors that affect the mechanical properties and deformation mechanisms are discussed.

SYSTEMATIC SYNTHESIS METHOD AND PROTOTYPING OF FIXEDAXLE VEHICULAR ELECTRIFIED MECHANICAL TRANSMISSION

H. ZHANG,Z. ZHONG,X. CHEN 한국자동차공학회 2015 International journal of automotive technology Vol.16 No.4

In the process of mechanism creative design, structure synthesis is the primary and the most important issue. This paper proposes a systematic and automatic synthesizing method of fixed-axle gear sets by means of morphological analysis. And the process is implemented to synthesize Electrified Mechanical Transmission (EMT) schemes which are parallel hybrid electric transmission composed of fixed-axle gear sets. First, independent design parameters as well as feasibility constraints and consistency conditions are defined by analyzing the structure and functions of EMT. According to these boundary conditions, structure variables such as the quantity of components and their connection relationship are solved. Then, the scheme quantity of each structure type is synthesized. Secondly, based on the abstraction of practical mechanisms with topology models, the corresponding adjacency matrixes are derived, and they are used to filtering unqualified schemes and retrieve all potential transmission paths of the remaining schemes. These potential transmission paths are further used to find out the layout and operating mode of each scheme. Finally, all schemes satisfying the structural and functional requirements are synthesized. For example, one EMT prototype is built based on one of the final schemes found and an ICE car is modified to adapt to such transmission. Vehicle test results verify the effectiveness and feasibility of the chosen transmission scheme.

SIMULATION OF THE VERTICAL BENDING FATIGUE TEST OF A FIVE-LINK REAR AXLE HOUSING

X. WANG,W. XU,Y. HUANG,M. ZHONG,H. FAN 한국자동차공학회 2012 International journal of automotive technology Vol.13 No.6

This study seeks a practical method for simulating the vertical bending fatigue test of the BANJO housing of a five-link rear axle. Linear static and transient dynamic finite element models are constructed for the rear axle in which the rubber bushings and the bearings of the axle shafts are reasonably modeled with solid and shell elements, respectively, for simplicity. The calculated results are compared with the measured strain histories, and the results indicate that the finite element models constructed are reasonable. The hypothesis of equal fatigue damage is applied to determine the Hainan proving ground driving life prediction that is equivalent to the constant amplitude fatigue life in the vertical bending fatigue test.