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.

β-Catenin Regulates Hepatic Mitochondrial Function and Energy Balance in Mice

Lehwald, Nadja,Tao, Guo&#x2013,Zhong,Jang, Kyu Yun,Papandreou, Ioanna,Liu, Bowen,Liu, Bo,Pysz, Marybeth A.,Willmann, Jü,rgen K.,Knoefel, Wolfram T.,Denko, Nicholas C.,Sylvester, Karl G. Elsevier 2012 Gastroenterology Vol.143 No.3

<P><B>Background & Aims</B></P> <P>Wnt signaling regulates hepatic function and nutrient homeostasis. However, little is known about the roles of β-catenin in cellular respiration or mitochondria of hepatocytes.</P> <P><B>Methods</B></P> <P>We investigated β-catenin's role in the metabolic function of hepatocytes under homeostatic conditions and in response to metabolic stress using mice with hepatocyte-specific deletion of β-catenin and their wild-type littermates, given either saline (sham) or ethanol (as a model of binge drinking and acute ethanol intoxication).</P> <P><B>Results</B></P> <P>Under homeostatic conditions, β-catenin-deficient hepatocytes demonstrated mitochondrial dysfunctions that included impairments to the tricarboxylic acid cycle and oxidative phosphorylation (OXPHOS) and decreased production of adenosine triphosphate (ATP). There was no evidence for redox imbalance or oxidative cellular injury in the absence of metabolic stress. In mice with β-catenin-deficient hepatocytes, ethanol intoxication led to significant redox imbalance in the hepatocytes and further deterioration in mitochondrial function that included reduced OXPHOS, fatty acid oxidation (FAO), and ATP production. Ethanol feeding significantly increased liver steatosis and oxidative damage, compared with wild-type mice, and disrupted the ratio of nicotinamide adenine dinucleotide. β-catenin-deficient hepatocytes also had showed disrupted signaling of Sirt1/peroxisome proliferator-activated receptor-α signaling.</P> <P><B>Conclusions</B></P> <P>β-catenin has an important role in the maintenance of mitochondrial homeostasis, regulating ATP production via the tricarboxylic acid cycle, OXPHOS, and fatty acid oxidation; β-catenin function in these systems is compromised under conditions of nutrient oxidative stress. Reagents that alter Wnt-β-catenin signaling might be developed as a useful new therapeutic strategy for treatment of liver disease.</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.

Influence of crystallization treatment on structure, magnetic properties and magnetocaloric effect of Gd71Ni29 melt-spun ribbons

X.C. Zhong,H.Y. Yu,Z.W. Liu,R.V. Ramanujan 한국물리학회 2018 Current Applied Physics Vol.18 No.11

The influence of crystallization treatment on the structure, magnetic properties and magnetocaloric effect of Gd71Ni29 melt-spun ribbons has been investigated in detail. Annealing of the melt-spun samples at 610 K for 30 min, a majority phase with a Fe3C-type orthorhombic structure (space group, Pnma) and a minority phase with a CrB-type orthorhombic structure (space group, Cmcm) were obtained in the amorphous matrix. The amorphous melt-spun ribbons undergo a second-order ferromagnetic to paramagnetic phase transition at 122 K. For the annealed samples, two magnetic phase transitions caused by amorphous matrix and Gd3Ni phases occur at 82 and 100 K, respectively. The maximum magnetic entropy change (–ΔSM)max is 9.0 J/(kgˑK) (5T) at 122 K for the melt-spun ribbons. The values of (–ΔSM)max in annealed ribbons are 1.0 and 5.7 J/(kgˑK), corresponding to the two adjacent magnetic transitions.

Thermal stability, magnetic and magnetocaloric properties of Gd55Co35M10 (M = Si, Zr and Nb) melt-spun ribbons

X.C. Zhong,D.L. Jiao,H. Zhang,W.Q. Qi,Z.W. Liu,R.V. Ramanujan 한국물리학회 2018 Current Applied Physics Vol.18 No.12

The thermal stability, magnetic and magnetocaloric properties of Gd55Co35M10 (M=Si, Zr and Nb) melts-pun ribbons were studied. The relatively high reduced glass transition temperature (Tx1/Tm > 0.60) and low melting point (Tm) resulted in excellent glass forming ability (GFA). The Curie temperatures (TC) of melt-spun amorphous ribbons Gd55Co35M10 for M=Si, Zr and Nb were 166, 148 and 173 K, respectively. For a magnetic field change of 2 T, the values of maximum magnetic entropy change (−ΔSM)max for Gd55Co35Si10, Gd55Co35Zr10 and Gd55Co35Nb10 were found to be 2.86, 4.28 and 4.05 J kg−1K−1, while the refrigeration capacity (RC) values were 154, 274 and 174 J kg–1, respectively. The RCFWHM values of amorphous alloys Gd55Co35M10 (M=Si, Zr and Nb) are comparable to or larger than that of LaFe11.6Si1.4 crystalline alloy. Large values of (−ΔSM)max and RC along with good thermal stability make Gd55Co35M10 (M=Si, Zr and Nb) amorphous alloys be potential materials for magnetic cooling operating in a wide temperature range from 150 to 175 K, e.g., as part of a gas liquefaction process.

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.

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.

Effects of Forage:Concentrate Ratio on Growth Performance, Ruminal Fermentation and Blood Metabolites in Housing-feeding Yaks

Chen, G.J.,Song, S.D.,Wang, B.X.,Zhang, Z.F.,Peng, Z.L.,Guo, C.H.,Zhong, J.C.,Wang, Y. Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.12

The objective of this study was to determine the effect of forage: concentrate ratio (F:C) on growth performance, ruminal fermentation and blood metabolites of housing-feeding yaks. Thirty-two Maiwa male yaks (initial body weight = $207.99{\pm}3.31kg$) were randomly assigned to four dietary treatments (8 yaks per treatment). Experimental diets were: A, B, C, D which contained 70:30, 60:40, 50:50 and 40:60 F:C ratios, respectively. Dry matter intake and average daily gain in yaks fed the C and D diets were greater (p<0.05) than yaks fed the A and B diets. No differences were found in ruminal $NH_3-N$, total volatile fatty acids, acetate, butyrate, valerate, and isovalerate concentrations. The propionate concentration was increased (p<0.05) in the C and D groups compared with the A and B diets. In contrast, the acetate to propionate ratio was decreased and was lowest (p<0.05) in the C group relative to the A and B diets, but was similar with the D group. For blood metabolites, no differences were found in serum concentrations of urea-N, albumin, triglyceride, cholesterol, low density lipoprotein, alanine aminotransferase, and aspartate aminotransferase (p>0.05) among treatments. Treatment C had a higher concentration of total protein and high density lipoprotein (p<0.05) than A and B groups. In addition, there was a trend that the globulin concentration of A group was lower than other treatments (p = 0.079). Results from this study suggest that increasing the level of concentrate from 30% to 50% exerted a positive effect on growth performance, rumen fermentation and blood metabolites in yaks.

Investigation on the Unlubricated Sliding Tribological Properties of Ti–20Zr–6.5Al–4V Alloy at Elevated Temperatures

H. Zhong,L. Q. Yang,Y. Yue,C. P. Zhang,F. X. Jin,M. Gu,M. Z. Ma 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.12

In this study, unlubricated sliding friction and wear properties of a recently-developed TiZr-based alloy (Ti–20Zr–6.5Al–4V, TZ20 hereafter) were tested at elevated temperatures ranging from room temperature to 673 K. After the tribologicaltests, worn surface and cross-section of TZ20 alloy were analyzed to illustrate its wear behavior. The results showed that thewear rate was increased firstly with the ambient temperature, which then decreased when the temperature exceeded criticaltransition temperature (473 K). Also, the dominant wear mechanisms changed from adhesive wear at room temperature toabrasive wear at 473 K, and then to mild abrasive wear at highest ambient temperature of 673 K. The variations of wearbehaviors could be attributed to tribo-oxide layer formed during sliding process. At ambient temperature of 673 K, the tribooxidelayer formed on the surface was thicker and more compact, and showed more obvious protective role on tribologicalproperties of TZ20 alloy.