Synthesis, optical properties, and energy transfer of Ce³⁺/Tb³⁺ co-doped M_yGdF_x (M=Li, Na, K)

Cao, C.,Luo, Z.,Guo, S.,Cao, R.,Noh, H.M.,Jeong, J.H.,Xie, A. Pergamon 2014 Spectrochimica acta. Part A, Molecular and biomole Vol.133 No.-

<P>Through a solid-state reaction method, the Ce3+/Tb3+ co-doped MyGdFx (M = Li, Na, K; x = 3, 4, 6; y = 0, 1, 3) system samples have been synthesized by controlling the annealing temperatures and the ratios of raw materials. The samples were characterized by X-ray diffraction (XRD) patterns, photoluminescence (PL) excitation and emission spectra as well as luminescent dynamic decay curves. The experimental results suggest that the LiF is more difficult to react with the prepared material compared that of NaF or KF under similar reaction conditions. The samples crystallized in different crystalline phases. The energy transfer from Ce3+ to Tb3+ or Ce3+ to Gd3+ to Tb3+ has been observed in all the samples. The Ce3+ and Tb3+ present different optical properties for they are sensitive to the local environment. In addition, the deduced lifetime of Tb3+ D-5(4) -> F-7(5) transition decreases in the same system samples with the annealing temperature increasing. The deduced lifetime of Tb3+ D-5(4) -> F-7(5) also decreases with the increase of the KF concentration in the KF system samples. (C) 2014 Elsevier B.V. All rights reserved.</P>

R&D Status of High-current Accelerators at IFP

J. J. Deng,J. S. Shi,W. P. Xie,L. W. Zhang,K. Z. Zhang,S. P. Feng,J. Li,M. Wang,Y. He,L. S. Xia,Z. Y. Dai,H. T. Li,L. Wen,S. F. Chen,X. Li,Q. G. Lai,M. H. Xia,Y. C. Guan,S. Y. Song,L. Chen 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.61

High-current accelerators have many important applications in Z-pinches, high-power microwaves, and free electron lasers, imploding liners and radiography and so on. Research activities on Zpinches, imploding liners, radiography at the Institute of Fluid Physics (IFP) are introduced. Several main high-current accelerators developed and being developed at IFP are described, such as the Linear Induction Accelerator X-Ray Facility Upgrade (LIAXFU, 12 MeV, 2.5 kA, 90 ns), the Dragon-I linear induction accelerator (20 MeV, 2.5 kA, 60 ns), and the Primary Test Stand for Z-pinch (PTS, 10 MA, 120 ns). The design of Dragon-II linear induction accelerator (20 MeV, 2.5 kA, 3 × 60 ns) to be built will be presented briefly.

Intramuscular Administration of Zinc Metallothionein to Preslaughter Stressed Pigs Improves Anti-oxidative Status and Pork Quality

Li, L.L.,Hou, Z.P.,Yin, Y.L.,Liu, Y.H.,Hou, D.X.,Zhang, B.,Wu, G.Y.,Kim, S.W.,Fan, M.Z.,Yang, C.B.,Kong, X.F.,Tang, Z.R.,Peng, H.Z.,Deng, D.,Deng, Z.Y.,Xie, M.Y.,Xiong, H.,Kang, P.,Wang, S.X. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.5

This study was conducted to determine the effects of exogenous zinc-metallothionein (Zn-MT) on anti-oxidative function and pork quality. After feeding a corn-soybean meal-based diet for two weeks, 48 pigs ($Duroc{\times}Landrace{\times}Chinese\;Black Pig$) were assigned randomly to four groups. Pigs in Group 1 were maintained under non-stress conditions, whereas pigs in Groups 2, 3 and 4 were aggressively handled for 25 min to produce stress. Pigs in Groups 1, 2, 3, and 4 received intramuscular administration of saline (control group; CON), 0 (negative control group; NCON), 0.8 (low dose group; LOW), and 1.6 (high dose group; HIGH) mg rabbit liver Zn-MT per kg body weight, respectively. Pigs were slaughtered at 3 and 6 h post-injection. Zn-MT treatment increased (p<0.05) the activities of superoxide dismutase (SOD) and glutathione-peroxidase (GSH-PX) while decreasing the concentration of malondialdehyde (MDA) in liver. These responses were greater (p<0.05) at 6 h than at 3 h post Zn-MT injection. Zn-MT treatment increased (p<0.05) hepatic SOD mRNA levels in a time and dose-dependent manner and decreased (p<0.05) serum glutamate-pyruvate transaminase and lactate dehydrogenase activities (indicators of tissue integrity). Zn-MT administration decreased (p<0.05) lactate concentration and increased (p<0.05) pH and water-holding capacity in the longissimus thorasis meat. Collectively, our results indicate that intramuscular administration of Zn-MT to pre-slaughter stressed pigs improved tissue anti-oxidative ability and meat quality.

A Phase 3 Evaluation of Daclatasvir plus Asunaprevir in Treatment-Naive Patients with Chronic HCV Genotype 1b Infection

( L. Wei ),( F. Wang ),( M. Zhang ),( J. Jia ),( A.A. Yakovlev ),( W. Xie ),( E.Z. Burnevich ),( J. Niu ),( Y.J. Jung ),( X. Jiang ),( M. Xu ),( X. Chen ),( Q. Xie ),( J. Li ),( J. Hou ),( H. Tang ),( 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Background/Aims: Treatment-naive GT 1b-infected patients from mainland China, South Korea and Russia were assessed for SVR at follow-up week 12 (SVR12) after receiving daclatasvir (60 mg, QD) and asunaprevir (100 mg, BID) (DCV+ASV). Methods: Patients were randomized 3:1 to receive DCV+ASV (24 weeks; immediate treatment [IM]) or 12 weeks of placebo followed by DCV+ASV (24 weeks; placebo-deferred treatment [PD]). The primary endpoint was to evaluate SVR12 in the IM arm to the historical rate for peginterferon/ribavirin (70%). Secondary endpoints included overall safety and safety comparisons between the treatment arms during the first 12 weeks. Results: 207 patients were randomized to IM (n=155) or PD (n=52); Asian (86%), female (59%), IL28B CC genotype (68%) and median age 49 (range 18-73) years; cirrhosis (13%), HCV RNA ≥6x106 IU/mL (53%). SVR12 in the IM arm was 92% and broadly unaffected by most baseline factors assessed (Figure); SVR12 was higher in patients without (96%) baseline NS5A-L31M/V or Y93H polymorphisms. There were 6 virologic breakthroughs, 6 relapses and 1 detectable HCV RNA at end-of-treatment in the IM arm. Safety was mostly comparable between the two arms during the first 12 weeks. The most frequent adverse events (AEs; ≥5%) during DCV+ASV (24 weeks) treatment in both arms were aminotransferase, bilirubin and INR elevations, hypertension, fatigue and respiratory tract infections; the most frequent treatment-emergent grade 3/4 laboratory abnormalities were aminotransferase (≤4.5%) and hematologic, lipase and total bilirubin abnormalities (≤2%); one patient (IM) discontinued DCV+ASV for aminotransferase elevations, nausea and jaundice (all reversible); one patient PD) discontinued DCV+ASV for a fatal AE unrelated to treatment. Conclusions: These data demonstrate that DCV+ASV is a highly efficacious and well tolerated treatment for treatment-naive HCV GT 1b-infected patients. Those treated immediately with DCV+ASV achieved a 92% SVR12 rate which was unaffected by factors known to attenuate response to interferon.

A correlation-based analysis on wind-induced interference effects between two tall buildings

Xie, Z.N.,Gu, M. Techno-Press 2005 Wind and Structures, An International Journal (WAS Vol.8 No.3

Wind-induced mean and dynamic interference effects of tall buildings are studied in detail by a series of wind tunnel tests in this paper. Interference excitations of several types of upwind structures of different sizes in different upwind terrains are considered. Comprehensive interference characteristics are investigated by artificial neural networks and correlation analysis. Mechanism of the wakes vortex-induced resonance is discussed, too. Measured results show significant correlations exist in the distributions of the interference factors of different configurations and upwind terrains and, therefore, a series of relevant regression equations are proposed to simplify the complexity of the multi-parameter wind induced interference effects between two tall buildings.

Applications of conservation integral to indentation with a rigid punch

Xie, Y.J.,Lee, K.Y.,Hu, X.Z.,Cai, Y.M. Pergamon Press ; Elsevier Science Ltd 2009 Engineering fracture mechanics Vol.76 No.7

When a substrate of the brittle material is indented by a relatively rigid, square-ended punch, a singular stress field and K-dominant region will arise at the near-surface adjacent to the punch corners. The singularity of this stress field is identical with the mode I crack. The stress intensity factor in this case represents the intensification of the stress fields induced by indentation. In present article, a new method to determine the stress intensity factors of the indentation problems is developed based on the conservation law. The physical meanings of the proposed method and some numerical analysis have been investigated.

Comparison of Axi-symmetric Single-Hole Nozzle with Multi-Hole Sac Nozzles

( M. C. Lai ),( Y. Zheng ),( X. Xie ),( K. Im ),( S. Moon ),( Z. Liu ),( J. Gao ),( J. Wang ),( J. M. Shi ),( R. E. Winsor ) 한국액체미립화학회 2010 한국액체미립화학회 학술강연회 논문집 Vol.2010 No.-

It is well know that the internal flow field and nozzle geometry affect the spray behavior, but without high-speed microscopic visualization, it is difficult to characterize the spray structure in details. Single-hole Diesel injectors have been used in fundamental spray research, while most direct-injection engines use multi-hole nozzle to tailor the fuel spray to the combustion chamber geometry. Recent engine trends also use smaller orifice and higher injection pressure. This paper discussed the quasi-steady near-nozzle Diesel spray structures of an axisymmetric single-hole nozzle and a symmetric two-hole nozzle configuration, with a nominal nozzle size of 130 ㎛. Both nozzle holes originate from a sac of identical geometry, but different flow structure inside the nozzle cause significant difference in the observed flow structure near the nozzle exit. The ultrafast fast Phase-contrast X-ray images revealed unique surface and internal morphology of the fuel sprays that can be identified. The two-hole nozzle produces much more unstable jet structure under same injection conditions. The early wavelength developed in the jet is measured to be 30~80 ㎛, depending on the injection conditions. The differences between the nozzle configurations are investigated using CFD simulation. The results show that the three-dimensional fluid flow entering the two-hole nozzle generates stronger streamline curvature and stream-wise vortices which are by default absent in the axisymmetric single-hole nozzle. It also produces thicker shear layer and higher turbulence. The interactions of downwash entrance flow with turbulence potentially enhance the instability and produce wider spray cone angles. The number of holes also has interesting effects on the strength of the vortices and the downwash.

Effects of Dietary Methionine Levels on Choline Requirements of Starter White Pekin Ducks

Wen, Z.G.,Tang, J.,Xie, M.,Yang, P.L.,Hou, S.S. Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.12

A $2{\times}5$ factorial experiment, using 2 dietary methionine levels (0.28% and 0.48%) and 5 dietary choline levels (0, 394, 823, 1,239, and 1,743 mg/kg), was conducted to study the effects of dietary methionine status on choline requirements of starter white Pekin ducks from 7 to 28 days of age. Four hundred eighty 7-d-old male White Pekin ducks were randomly allotted to ten dietary treatments, each containing 6 replicate pens with 8 birds per pen. At 28 d of age, weight gain, feed intake, and feed/gain were measured and the legs of all ducks from each pen were examined for incidence of perosis. Perosis and growth depression were observed in choline-deficient ducks and supplementation of choline reduced perosis and significantly increased weight gain and feed intake regardless of dietary methionine levels (p<0.05). In addition, significant positive effects of dietary methionine supplementation on weight gain, feed intake, and feed/gain were observed at any choline level (p<0.05). Supplementation of 1,743 mg/kg choline in diets alleviated the depression of weight gain and feed intake caused by methionine deficiency at 0.28% methionine level. The interaction between choline and methionine influenced weight gain and feed intake of ducks (p<0.05). At 0.28% methionine level, 1,743 mg/kg choline group caused 4.92% and 3.23% amount of improvement in weight gain and feed intake compared with 1,239 mg/kg choline group, respectively. According to the broken-line regression, the choline requirements of starter Pekin ducks for weight gain and feed intake were 1,472 and 1,424 mg/kg at 0.28% methionine level and 946 and 907 mg/kg at 0.48% methionine level, respectively. It suggested the choline recommendations of starter Pekin ducks on a semi-purified diet were 1448 mg/kg at 0.28% methionine level and 927 mg/kg at 0.48% methionine level, respectively. Compared with the adequate methionine level, menthionine deficiency markedly increased the choline requirements of ducks.

Characterization of short-duration high-energy ball milled WC-Co powders and subsequent consolidations

Raihanuzzaman, R.M.,Jeong, T.S.,Ghomashchi, R.,Xie, Z.,Hong, S.J. Elsevier Sequoia 2014 JOURNAL OF ALLOYS AND COMPOUNDS Vol.615 No.suppl1

The aim of this study was to observe the effect of short-duration, high-energy ball milling on the mechanical properties of sintered WC-Co. Mixed powders of WC-7.5wt% nano Co were ball milled at three different time using WC vial and balls, while other parameters were kept constant. The powders were then consolidated using spark plasma sintering. Density and hardness of the sintered samples were measured as a function of milling time, used to mix the powders prior to consolidation. It was found that both density and hardness increased with milling time, with hardness reaching a maximum of 14.95GPa for the sample milled for 10min. Microstructures of the sintered samples suggested a slight decline in grain size and increase in Co distribution with increasing milling time. It was also evident that milling of WC-Co powders resulted in the sintered samples having overall irregular shaped grains.

Short-circuiting in fullerene devices studied by in situ electrical measurement in high vacuum and infrared imaging analysis?

H.R. Wu,M.L. Wang,Q.L. Song,Y. Wu,Z.T. Xie,X.D. Gao,X.M. Ding,X.Y. Hou 한국물리학회 2007 Current Applied Physics Vol.7 No.3

In the present work, currentvoltage (IV) characteristics of fullerene devices (ITOnC60nAl) are reexamined byin situelectrical mea-surement in high vacuum and by infrared imaging analysis. Two kinds ofIV curves are detected: ‘ohmic’ and nonohmic. Degradationprocesses of the two dierent devices are measured, and ‘ohmic’ degradation processes are ascribed to short-circuiting. ITOnC60nAldevices in high vacuum are conrmed to be intrinsically nonohmic. Surface temperature distribution of the two dierent devices is mea-buers are inserted between fullerene layer and cathode and this is found to be eective.