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.

Numerical studies on the effects of the lateral boundary on soil-structure interaction in homogeneous soil foundations

Li, Z.N.,Li, Q.S.,Lou, M.L. Techno-Press 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.20 No.4

In this paper, the finite element method is applied to investigate the effect of the lateral boundary in homogenous soil on the seismic response of a superstructure. Some influencing factors are presented and discussed, and several parameters are identified to be important for conducting soil-structure interaction experiments on shaking tables. Numerical results show that the cross-section width L, thickness H, wave propagation velocity and lateral boundaries of soil layer have certain influences on the computational accuracy. The dimensionless parameter L/H is the most significant one among the influencing factors. In other words, a greater depth of soil layer near the foundation should be considered in shaking table tests as the thickness of the soil layer increases, which can be regarded as a linear relationship approximately. It is also found that the wave propagation velocity in soil layer affects the numerical accuracy and it is suggested to consider a greater depth of the soil layer as the wave propagation velocity increases. A numerical study on a soil-structure experimental model with a rubber ring surrounding the soil on a shaking table is also conducted. It is found the rubber ring has great effect on the soil-structure interaction experiments on shaking table. The experimental precision can be improved by reasonably choosing the elastic parameter and width of the rubber ring.

Microstructural Stability and Creep Performance of a Novel Low-Cost Single Crystal Superalloy

Z. H. Tan,X. G. Wang,Y. L. Du,Y. M. Li,Y. H. Yang,J. L. Liu,J. D. Liu,J. G. Li,Y. Z. Zhou,X. F. Sun 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

The increasing pursuit of advanced aero-engines with lower ratio between the cost and performance has greatly promotedthe demanding of single crystal superalloys characterized by low cost and outstanding temperature capability. In this study,a novel low-cost single crystal superalloy was designed and the creep tests as well as micro-characterization were carried outon the experimental alloy. The results illustrated that the novel single crystal alloy exhibited an ideal microstructural stabilitywithout precipitating TCP phases, after long-term thermal exposure at the ultimate service temperature of third generationsingle crystal superalloys. Moreover, the experimental alloy with only 3 wt% Re addition demonstrated remarkable creepresistance and maintained a very low minimum creep rate at 1100 °C/137 MPa and 1120 °C/137 MPa, while the accumulationand coalescence of micro-pores had eventually led to the alloy fracture. Apart from that, the compact interfacial dislocationnetworks the 2nd γ′ phase were observed after high-temperature creep rupture, and the typical a < 010 > superdislocationswith relatively poor mobility was found at 1120 °C. At 760 °C/800 MPa, both the minimum creep velocity and entire creepstain was increased evidently, however, the ultimate creep rupture life of the alloy had still reached 200 h. The correspondingdeformation mechanism was identified as the combination of superdislocation pairs shearing and a/3 < 121 > partial dislocationcutting the γ′ phase with a SISF being generated. In general, the novel single crystal alloy characterized by remarkablemechanical properties and cost reduction possesses a great potential for future application in the advanced aircraft engines.

Effects of Nitrogen Application Rate on the Yields, Nutritive Value and Silage Fermentation Quality of Whole-crop Wheat

Li, C.J.,Xu, Z.H.,Dong, Z.X.,Shi, S.L.,Zhang, J.G. Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.8

Whole-crop wheat (Triticum aestivum L.) as forage has been extensively used in the world. In this study, the effects of N application rates on the yields, nutritive value and silage quality were investigated. The N application rates were 0, 75, 150, 225, and 300 kg/ha. The research results indicated that the dry matter yield of whole-crop wheat increased significantly with increasing N rate up to 150 kg/ha, and then leveled off. The crude protein content and in vitro dry matter digestibility of whole-crop wheat increased significantly with increasing N up to 225 kg/ha, while they no longer increased at N 300 kg/ha. On the contrary, the content of various fibers tended to decrease with the increase of N application. The content of lactic acid, acetic acid and propionic acid in silages increased with the increase of N rate (p<0.05). The ammonia-N content of silages with higher N application rates (${\geq}225kg/ha$) was significantly higher than that with lower N application rates (${\leq}150kg/ha$). Whole-crop wheat applied with high levels of N accumulated more nitrate-N. In conclusion, taking account of yields, nutritive value, silage quality and safety, the optimum N application to whole-crop wheat should be about 150 kg/ha at the present experiment conditions.

Numerical studies on the effects of the lateral boundary on soil-structure interaction in homogeneous soil foundations

Z. N. Li,Q. S. Li,M. L. Lou 국제구조공학회 2005 Structural Engineering and Mechanics, An Int'l Jou Vol.20 No.4

In this paper, the finite element method is applied to investigate the effect of the lateral boundary in homogenous soil on the seismic response of a superstructure. Some influencing factors are presented and discussed, and several parameters are identified to be important for conducting soil-structure interaction experiments on shaking tables. Numerical results show that the cross-section width L, thickness H, wave propagation velocity and lateral boundaries of soil layer have certain influences on the computational accuracy. The dimensionless parameter L/H is the most significant one among the influencing factors. In other words, a greater depth of soil layer near the foundation should be considered in shaking table tests as the thickness of the soil layer increases, which can be regarded as a linear relationship approximately. It is also found that the wave propagation velocity in soil layer affects the numerical accuracy and it is suggested to consider a greater depth of the soil layer as the wave propagation velocity increases. A numerical study on a soil-structure experimental model with a rubber ring surrounding the soil on a shaking table is also conducted. It is found the rubber ring has great effect on the soil-structure interaction experiments on shaking table. The experimental precision can be improved by reasonably choosing the elastic parameter and width of the rubber ring.

Effects of Maturity Stages on the Nutritive Composition and Silage Quality of Whole Crop Wheat

Xie, Z.L.,Zhang, T.F.,Chen, X.Z.,Li, G.D.,Zhang, J.G. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.10

The changes in yields and nutritive composition of whole crop wheat (Triticum aestivum L.) during maturation and effects of maturity stage and lactic acid bacteria (LAB) inoculants on the fermentation quality and aerobic stability were investigated under laboratory conditions. Whole crop wheat harvested at three maturation stages: flowering stage, milk stage and dough stage. Two strains of LAB (Lactobacillus plantarum: LAB1, Lactobacillus parafarraqinis: LAB2) were inoculated for wheat ensiling at $1.0{\times}10^5$ colony forming units per gram of fresh forage. The results indicated that wheat had higher dry matter yields at the milk and dough stages. The highest water-soluble carbohydrates content, crude protein yields and relative feed value of wheat were obtained at the milk stage, while contents of crude fiber, neutral detergent fiber and acid detergent fiber were the lowest, compared to the flowering and dough stages. Lactic acid contents of wheat silage significantly decreased with maturity. Inoculating homofermentative LAB1 markedly reduced pH values and ammonia-nitrogen ($NH_3$-N) content (p<0.05) of silages at three maturity stages compared with their corresponding controls. Inoculating heterofermentative LAB2 did not significantly influence pH values, whereas it notably lowered lactic acid and $NH_3$-N content (p<0.05) and effectively improved the aerobic stability of silages. In conclusion, considering both yields and nutritive value, whole crop wheat as forage should be harvested at the milk stage. Inoculating LAB1 improved the fermentation quality, while inoculating LAB2 enhanced the aerobic stability of wheat silages at different maturity stages.

Kinetics of Zn2+-induced Brain Type Creatine Kinase Unfolding and Aggregation

μ, H.,L체, Z. R.,Park, D.,Kim, B. C.,Bhak, J.,Zou, F.,Yang, J. M.,Li, S.,Park, Y. D.,Zou, H. C. HUMANA PRESS INC 2010 Applied biochemistry and biotechnology Vol.160 No.5

Investigating energy partitioning during photosynthesis using an expanded quantum yield convention

Ahn, T.K.,Avenson, T.J.,Peers, G.,Li, Z.,Dall'Osto, L.,Bassi, R.,Niyogi, K.K.,Fleming, G.R. Elsevier Science Publishers [etc.] 2009 Chemical physics Vol.357 No.1

In higher plants, regulation of excess absorbed light is essential for their survival and fitness, as it enables avoidance of a build up of singlet oxygen and other reactive oxygen species. Regulation processes (known as non-photochemical quenching; NPQ) can be monitored by steady-state fluorescence on intact plant leaves. Pulse amplitude modulated (PAM) measurements of chlorophyll a fluorescence have been used for over 20 years to evaluate the amount of NPQ and photochemistry (PC). Recently, a quantum yield representation of NPQ (Φ<SUB>NPQ</SUB>), which incorporates a variable fraction of open reaction centers, was proposed by Hendrickson et al. [L. Hendrickson, R.T. Furbank, W.S. Chow, Photosynth. Res. 82 (2004) 73]. In this work we extend the quantum yield approach to describe the yields of reversible energy-dependent quenching (Φ<SUB>qE</SUB>), state transitions to balance PC between photosystems II and I (Φ<SUB>qT</SUB>), and photoinhibition quenching associated with damaged reaction centers (Φ<SUB>qI</SUB>). We showed the additivity of the various quantum yield components of NPQ through experiments on wild-type and npq1 strains of Arabidopsis thaliana. The quantum yield approach enables comparison of Φ<SUB>qE</SUB> with data from a variety of techniques used to investigate the mechanism of qE. We showed that Φ<SUB>qE</SUB> for a series of A. thaliana genotypes scales linearly with the magnitude of zeaxanthin cation formation, suggesting that charge-transfer quenching is largely responsible for qE in plants.

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.

Synthesis and evaluation of a novel chiral derivatization reagent for resolution of carboxylic acid enantiomers by RP-HPLC

Li, L.P.,Jin, M.N.,Shi, Q.,Xu, C.Y.,Jiang, Y.Z.,Lee, Y.I.,Min, J.Z. Academic Press 2017 Microchemical Journal Vol. No.

<P>A novel derivatization reagent, N-[1-Oxo-5-(triphenylphosphonium)pentyl]-(S)-3-aminopyrrolidine (OTPA), with triphenylphosphine (TPP) as a basic structure carrying a permanent positive charge was developed for the enantiomeric separation of chiral carboxylic acids by high-performance liquid chromatography (HPLC). OTPA reacted with the carboxylic acids at 40 degrees C within 90 min in the presence of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and 1-hydroxybenzotriazole (HOBt). The degree of epimerization (racemization) during the derivatization reaction was negligible. The separability of the diastereomers was evaluated in terms of their resolution value (Rs). The Rs values of the derivatives of non-steroidal anti-inflammatory drugs (NSAIDs), which were selected as the representative carboxylic acids, were completely separated by reversed-phase chromatography using an ODS (4.6 mm x 150 mm I.D., 5.0 mu m) column. The resolution Rs values were 1.54-2.23 for the evaluated carboxylic acids and the OTPA-derivatization was also effective for the enantiomeric separation of chiral carboxylic acids. The calibration curves (r(2) > 0.9971) were linear over the concentration range of 0.0125-1.25 mM for each enantiomer of ketoprofen (KET), and naproxen (NAP), 0.05-1.0 mM for each enantiomer of ibuprofen (IBU), 2-phenylpropionic acid (PPA), and loxoprofen (LOX), and 0.05-1.25 mM for each enantiomer of PBA. The limit of detection (S/N = 3) for each of the enantiomers of the NSAIDs and chiral carboxylic acid enantiomers was 1.4-7.6 mu mol/L. The inter-day and intra-day assay precisions were all <6.77% and the mean recoveries (%) of the NSAIDs and chiral carboxylic acids from the spiked human plasma were 95.27-101.12%. The derivatization followed by HPLC-UV enabled the separation and detection of NAP in human plasma with simple pretreatment. (C) 2017 Elsevier B.V. All rights reserved.</P>