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 Keratinase on Performance, Nutrient Utilization, Intestinal Morphology, Intestinal Ecology and Inflammatory Response of Weaned Piglets Fed Diets with Different Levels of Crude Protein

Wang, D.,Piao, X.S.,Zeng, Z.K.,Lu, T.,Zhang, Q.,Li, P.F.,Xue, L.F.,Kim, S.W. Asian Australasian Association of Animal Productio 2011 Animal Bioscience Vol.24 No.12

Two experiments were conducted to investigate the in vitro ability of keratinase to hydrolyze soybean glycinin and ${\beta}$-conglycinin and to evaluate the in vivo effects of keratinase when included in corn-soybean diets with different levels of crude protein and fed to nursery pigs. In experiment 1, a saturated keratinase solution (1 ml) was added to two blank controls of either glycinin or ${\beta}$-conglycinin resulting in the hydrolysis of 94.74% glycinin and 88.89% ${\beta}$-conglycinin. In experiment 2, 190 pigs (8.3${\pm}$0.63 kg BW) were allotted to one of four treatments in a 2${\times}$2 factorial arrangement on the basis of body weight, and sex was balanced among the pens. The effects of crude protein (19 vs. 22%) and keratinase (0 vs. 0.05%) were studied. Each treatment was applied to six pens with seven (two pens) or eight pigs per pen. Pigs were fed the experimental diets for 21 d. Weight gain and feed conversion ratio were improved (p<0.05) with keratinase supplementation while feed intake was reduced (p<0.05). Keratinase supplementation increased (p<0.05) the apparent total tract digestibility of dry matter, energy, crude protein and phosphorus. Keratinase supplementation also increased n-butyric acid in the cecum and colon, lactobacilli and total anaerobe counts in the colon as well as the ratio of villus height to crypt depth in the ileum. Additionally, fecal score, ammonia nitrogen and branch chain volatile fatty acids in the colon, E. coli and total aerobe counts in the colon, crypt depth in the jejunum and ileum as well as serum interleukin-1 and interleukin-6 concentrations were also decreased (p<0.05) by keratinase supplementation. A reduction in dietary crude protein decreased (p<0.05) colon ammonia nitrogen concentration and cecal propionic acid and branch chain volatile fatty acid concentrations. In addition, cecal E. coli counts, colon total anaerobe counts, ileal crypt depth, and serum interleukin-1 and interleukin-6 concentrations were also decreased (p<0.05) with the reduction of dietary crude protein. With the exception of fecal scores, there were no significant interactions between crude protein and keratinase. This study provides evidence that dietary keratinase supplementation improved nursery pig performance by improving intestinal morphology and ecology, thus improving nutrient digestibility and alleviating the inflammatory response.

Characteristics of alkali-resistant Ni/MgAl₂O₄ catalyst for direct internal reforming molten carbonate fuel cell

Park, D.S.,Li, Z.,Devianto, H.,Lee, H.I. Pergamon Press ; Elsevier Science Ltd 2010 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY - Vol.35 No.11

Direct internal reforming - molten carbonate fuel cell (DIR-MCFC) has advantages of higher efficiency and smaller size. However, deactivation of the catalyst by alkali carbonate electrolytes poses a significant problem in MCFC. To solve this problem, Ni/MgO and Ni/MgAl<SUB>2</SUB>O<SUB>4</SUB> catalysts were compulsively mixed with a eutectic mixture of Li<SUB>2</SUB>CO<SUB>3</SUB> and Na<SUB>2</SUB>CO<SUB>3</SUB> prior to a methane steam reforming activity test. Activity of Ni/MgO rapidly decreased, while that of Ni/MgAl<SUB>2</SUB>O<SUB>4</SUB> remained steady due to good alkali resistance. To analyze the effects of alkali addition, N<SUB>2</SUB> adsorption-desorption, X-ray diffraction, temperature-programmed reduction and oxidation, scanning electron microscopy, and X-ray photoelectron spectroscopy experiments were carried out. Both Ni/MgO and Ni/MgAl<SUB>2</SUB>O<SUB>4</SUB> showed sintering of Ni and blocking of pores, which reduced the catalytic activity. However, Ni/MgAl<SUB>2</SUB>O<SUB>4</SUB> showed other positive effects such as stronger metal-support interaction and increased dissociative adsorption.

재래 흑돼지와 중국 재래돈간의 Melanocortin Receptor 1(MC1R) 유전자의 유전자형 분석

이성수,양보석,정진관,고서봉,오성종,양영훈,김규일,이찬동,풍서당 한국동물자원과학회 2001 한국축산학회지 Vol.43 No.1

PCR-RFLP analysis of Melanocortin receptor 1 (MC1R) gene was carried out to investigate the genotype distribution in Korean-Native and Chinese-Native pig breeds(Neijiang, Putian, Wannanhua and Jinhua). Allelic variants of MC1R in pigs were analyzed by digestion of BspH I , AccII and Hha I . Ncijiang. Wannanhua and Jinhua had only MC1R*2 allele which is considered to be typical genotype for Meishan and Large Black. Among 20 Korean-Native Pigs and 5 Putian pigs, 10 and 2 heads had the MC1R*3 allele (*2/3 or 3/3), respectively, which was detected in European pig breeds such as Hampshire, Large White, and Pietrain. The remaining animals possessed the genotype MC1R*2/2, probably reflecting the genetic introgression of MC1R*3 allele into Korean-Native and Putian pig breeds by the crossbreeding for improvement. The alleles MC1R*l and MC1R*4, which are considered to be typical allele for European Wild Boar with wild-type coat color and Duroc with red coat color, respectively, were not detected in pig breeds used in this experiment. These results indicate that the analysis of genotype frequencies of MC1R gene may be a useful tool for the conservation of Korean-Native and Chinese-Native pig breeds.

Effects of $1{\alpha}$-Hydroxycholecalciferol and Phytase on Growth Performance, Tibia Parameter and Meat Quality of 1- to 21-d-old Broilers

Han, J.C.,Yang, X.D.,Zhang, L.M.,Li, W.L.,Zhang, T.,Zhang, Z.Y.,Yao, J.H. Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.6

This experiment was conducted to investigate the effects of interaction between $1{\alpha}$-hydroxycholecalciferol ($1{\alpha}$-OH $D_3$) and phytase on growth performance, parameters of tibia and plasma, and meat quality of 1- to 21-d-old broilers. Two hundred and forty male, 1-d-old Arbor Acres broilers were randomly assigned to 20 cages, with 12 chicks per cage. Five treatments were designed, with four cages each. A 2${\times}$2 factorial experiment was designed to test 0 and 5 ${\mu}g/kg$ of $1{\alpha}$-OH $D_3$ in combination with 0 and 500 U/kg of phytase. A basal diet was formulated to contain 2.9 g/kg of non-phytate phosphorus (NPP), and the control diet was formulated to contain a normal level of NPP (4.5 g/kg). Results showed that $1{\alpha}$-OH $D_3$ alone increased tibia ash, contents of calcium and phosphate, breaking strength, concentrations of plasma calcium and phosphate, and water-holding capacity of breast and thigh meat, while it decreased growth of broilers. Phytase alone improved performance and tibia quality. Although growth of broilers was lower than that of the positive control when the diet was supplemented with $1{\alpha}$-OH $D_3$ and phytase, tibia quality was significantly improved by the addition of $1{\alpha}$-OH $D_3$ and phytase. These data suggest that interaction between $1{\alpha}$-OH $D_3$ and phytase at 2.9 g/kg of dietary NPP could significantly increase bone quality of 1- to 21-d-old broilers, while not improving growth performance.

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.

Four new sesqui-lignans isolated from Acanthopanax senticosus and their diacylglycerol acyltransferase (DGAT) inhibitory activity

Li, J.L.,Li, N.,Lee, H.S.,Xing, S.S.,Qi, S.Z.,Tuo, Z.D.,Zhang, L.,Li, B.B.,Chen, J.G.,Cui, L. Elsevier 2016 Fitoterapia Vol.109 No.-

<P>Four new sesqui-lignans, (7R, 7'R, 7 '' S, 8S, 8'S, 8 '' S)-4',5 ''-dihydroxy-3,5,3',4 ''-tetramethoxy-7,9':7',9-diepoxy4,8 ''-oxy-8,8'-sesquineo-lignan-7',9 ''-diol (1), (7R, 7'R, 7 '' S, 8S, 8'S, 8 '' S)-4',3'-dihydroxy-3,5,3',5',4'pentamethoxy-7,9':7',9-diepoxy-4,8'-oxy-8,8'-sesquineo-lignan-7',9'-diol (2), (7R, 7'R, 7'S, 8S, 8'S, 8'S)-3',4'dihydroxy-3,5,4',5 ''-tetramethoxy-7,9':7',9-diepoxy-4,8'-oxy-8,8'-sesquineo-lignan-7',9'-diol (3) and acanthopanax A (7) together with three known compounds (4-6) were isolated from the EtOAc-soluble extract of Acanthopanax senticosus. Their structures were elucidated on the basis of spectroscopic and physicochemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1 and DGAT2. Among them, compounds 1-6 were found to exhibit selective inhibitory activity on DGAT1 with IC50 values ranging from 61.1 1.3 to 97.7 1.1 111\4 and compound 7 showed selective inhibition of DGAT2 with IC50 value 93.2 1.2. (C) 2016 Elsevier B.V. All rights reserved.</P>

EFFECT OF GONADOTROPHINS ON FOLLICULAR STEROID HORMONE PRODUCTION IN HYPOPHYSECTOMISED HENS (Gallus domesticus)

Li, Z.D.,Koga, O.,Tanaka, K.,Fujihara, N. Asian Australasian Association of Animal Productio 1993 Animal Bioscience Vol.6 No.3

We assessed effects of ovine luteinizing hormone (oLH) and follicle-stimulating hormone (oFSH) on the granulose and theca layers from the four largest follicles, $F_1-F_4$ of hens which had been hypophysectomized 12 h before expected ovulation. Ovine LH (0.4 mg), oFSH (0.4 mg) or oLH in combination with oFSH (0.4 mg each) was injected intravenously 6 h after hypophysectomy. Progesterone, testosterone and $estradiol-17{\beta}$ levels of the granulose and theca layers which were removed 6 h after hormone injection, were measured by radioimmunoassay. Progesterone contents of $F_1-F_3$ granulosa layer at 12 h after hypophysectomy were much lower than those of control hens. This reduced progesterone level was restored partially by the injection of oLH alone for $F_1$, while no follicles responded to oFSH treatment. In contrast, the injection of oLH in combination with oFSH resulted in high progesterone content of the granulose layer from all four follicles. Progesterone content of the theca layer was negligible in all treatments. Simultaneous injection of oLH and oFSH also elevated $estradiol-17{\beta}$ level accumulating in the theca layer from all follicles, of which much higher concentrations of $estradiol-17{\beta}$ were observed when comparison were made to each of their corresponding controls. No appreciable change in testosterone contents of two layers was observed in the present experiments. These results suggest that oFSH augments function of oLH to stimulate the production of progesterone in the granulose layer and $estradiol-17{\beta}$ in the theca layer.

A novel Parzen probabilistic neural network based noncoherent detection algorithm for distributed ultra-wideband sensors

Li, B.,Zhou, Z.,Li, D.,Zou, W. Academic Press 2011 JOURNAL OF NETWORK AND COMPUTER APPLICATIONS - Vol.34 No.6

Ultra-wideband (UWB) has been widely recommended for significant commercial and military applications. However, the well-derived coherent structures for UWB signal detection are either computationally complex or hardware impractical in the presence of the intensive multipath propagations. In this article, based on the nonparametric Parzen window estimator and the probabilistic neural networks, we suggest a low-complexity and noncoherent UWB detector in the context of distributed wireless sensor networks (WSNs). A novel characteristic spectrum is firstly developed through a sequence of blind signal transforms. Then, from a pattern recognition perspective, four features are extracted from it to fully exploit the inherent property of UWB multipath signals. The established feature space is further mapped into a two-dimensional plane by feature combination in order to simplify algorithm complexity. Consequently, UWB signal detection is formulated to recognize the received patterns in this formed 2-D feature plane. With the excellent capability of fast convergence and parallel implementation, the Parzen Probabilistic Neural Network (PPNN) is introduced to estimate a posteriori probability of the developed patterns. Based on the underlying Bayesian rule of PPNN, the asymptotical optimal decision bound is finally determined in the feature plane. Numerical simulations also validate the advantages of our proposed algorithm.

Effects of a Stair-step Growth Pattern on Improvements in Meat Quality and Growth in Hanwoo Steers

Li, Z.H.,Lee, H.G.,Xu, C.X.,Hong, Z.S.,Jin, Y.C.,Yin, J.L.,Zhang, Q.K.,Piao, D.C.,Yang, U.M.,Choi, Y.J. Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.11

The present study was conducted to examine the effect of a stair-stepped feed intake pattern on growth, feed efficiency, and meat quality of Hanwoo steers. Twenty-seven 11-month-old Hanwoo steers were randomly divided into three groups. The control group was fed according to the Korean steer feeding program, and the other two groups were fed according to an alternated feeding schedule of 3-2-4-2 months. During the first three months of the experiment, treatment group 1 (T1) and treatment group 2 (T2) were fed 20% and 30% less than the control group, respectively. For the following two months, the T1 group was fed 20% more than the control group while the T2 group was fed 20% less than the control group. In the third step, T1 and T2 groups were fed 20% and 10% less, respectively, than the control group for four months. In the last two months, T1 and T2 groups were fed 20% more than the control group. After the stair-step feeding trial, steers were fed concentrated feed ad libitum for five months. The altered feed intake pattern did not affect daily body weight gain. However, daily feed intake tended to decrease and growth efficiency tended to increase in the two treatment groups compared to the control group. Altered feed intake also affected blood metabolite levels. The serum glucose and BUN level of the T1 group increased in the first re-fed period compared to the T2 and control groups. The serum cholesterol level of the T2 group decreased in the first restricted-re-fed growth period compared to the T1 and control groups. The serum NEFA levels of the two treatment groups increased from the first restricted period compared to the controls. The serum insulin level of the T2 group increased in the last period compared to the T1 and control groups. Regarding meat yield index, the control group was significantly higher than the T2 group (p<0.05). Regarding meat yield grade, the carcass back fat thickness of the T2 group was significantly higher than the control group (p<0.05). In marbling score, the T1 group was the highest (4.9), followed by the control group (4.1) and the T2 group (4.0). These results indicate that using a stair-stepped growth pattern (T1) can contribute to improvements in growth efficiency and muscle marbling.