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Process and properties of electroless Ni-W-B amorphous electrical resistance film

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 144-146页

作者： ZHU Xiao-yun GUO zhong-cheng XU Rui-dong The Centre of New Materials and Surface Engineering Research and Development Kunming University of Science and Technology Kunming 650093 China The Centre of New Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China The Centre of New Materials and Surface Engineering Research and DevelopmentKunming University of Science and Technology Kunming 650093 China

The process and properties of electroless plating Ni-W-B alloy have been studied. The results show that the deposits containing W and B are obtained, and the deposition rate of the bath is increased with increase of W content when a certain amount of sodium tungstate solution is added in the Ni-B bath. The Ni-W-B alloy is amorphous as deposition and its resistivity increases directly with the increase of W content in the coating, but decreases gradually with increasing the deposit thickness. XRD and SEM show that the distributions of W and B in the Ni-W-B alloy film are very uniform and dispersed without any segregation.

关键词： electroless Ni-W-B alloy electrical resistance film properties

TiB2 coating formed on nickel substrates by electroplating in molten salt of fluoride

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 132-135页

作者： LONG Jin-ming GUO zhong-cheng HAN Xia-yun Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China Faculty of Materials and Metallurgical Engineering Kunrning University of Science and Technology Kunming 650093 China

The TiB2 coatings deposited over nickel substrate by electroplating was investigated, which is in molten salt of a fluoride mixture involving KF, NaF, K2 TiF6 and KBF4. Effects of temperature, cathodic current density (Jc) and duration on the coating's formation were examined. The composition, morphology and structure of the coatings were characterized by scanning electron microscopy (SEM), energy dispersive X-ray detector (EDS) and X-ray diffraction (XRD). The results show that the coatings, with black, smooth and uniform appearance, are composed of predominating TiB2 and small amounts of nickel titanium oxide (Ni0.75 Ti0.125 O). The coatings show a nodular morphology and the grain size is dependent on the Jc and ranges about 1 - 10 μm. There is a linear relationship between the coating's thickness and the time of electrolysis within certain duration range. The reduction of the potassium can take place simultaneously with the electrochemical synthesis of TiB2 as the Jc is in excess of certain level. The hardness of the TiB2 coatings is likely to be deteriorated due to the presence of potassium and Ni0.75Ti0.125 O in the coatings.

关键词： TiB2 coating electroplating molten salt nickel microstructure

Numerical investigation of mass transfer behavior of a gas-liquid two‐phase Taylor flow in a microchannel by a volume‐of‐fluid multiphase flow system

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International Journal of Mechanical System Dynamics 2022年第3期2卷 253-264页

作者： Qiuwen zhong Zhen Jiao Wenhui nie Yan Li Ning Gu Jiangsu Key Laboratory for Biomaterials and Devices Southeast UniversityNanjingChina Joint Research Institute of Southeast University and Monash University SuzhouChina School of Chemistry and Chemical Engineering Southeast UniversityNanjingChina School of Biological Science and Medical Engineering Southeast UniversityNanjingChina

The microchannel reactor is the most commonly used microreaction technology,an innovative reaction system developed in recent *** study investigates the mass transfer behavior of a gas-liquid two‐phase Taylor flow in a microchannel by coupling the volume‐of‐fluid model and the species transport *** concentration distribution and the volumetric mass transfer coefficient of the gas solute are determined and discussed in *** simulation results reveal that the double‐circulation flow influences the concentration distribution in the liquid *** highest value is observed at the bubble's surface and decreases rapidly along the vertical direction of the *** increase of bubble velocity leads to a more apparent decreasing *** gas-liquid interface renewal rate of the bubble is accelerated with increasing bubble velocity,resulting in an increase in the average mass transfer rate in all regions of the bubble surface with an increase in bubble *** results also indicate that the liquid film area contributes the most to the mass transfer behavior due to the most significant proportion and average mass transfer rate of the liquid film among the bubble.

关键词： Taylor flow microchannel hydrodynamics mass transfer behavior CFD simulation gas-liquid interface

Effect of dietary nonphytate phosphorus on laying performance and small intestinal epithelial phosphate transporter expression in Dwarf pink-shell laying hens

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Journal of Animal Science and Biotechnology 2014年第3期5卷 333-339页

作者： Wei nie Ying Yang Jianmin Yuan zhong Wang Yuming Guo State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural University

This study examined the effects of various levels of dietary nonphytate phosphorus on laying performance and the expression patterns of phosphorus metabolism related genes in Dwarf pink-shell Jaying hens. A total of 405 28-week-old Dwarf pink-shell laying hens were fed the same corn-soybean basal meals but containing 0.20%, 0.25%, 0.30%, 0.35% or 0.40% nonphytate phosphorus. The results showed that feed intake, egg production, and average egg weights were quadratically correlated with dietary nonphytate phosphorus content （P 〈 0.05）, and the highest egg production, feed intake and average egg weights were achieved when dietary nonphytate phosphorus was at 0.3% （P 〈 0.05）. mRNA expression of intestinal sodium phosphorus co-transporter linearly decreased when dietary nonphytate phosphorus increased, mRNA and protein expression of intestinal calbindin and vitamin D receptor correlated quadratically with dietary nonphytate phosphorus, and the highest expression was found when dietary available phosphorus was at 0.2,5% to 0.3%. In conclusion, the ideal phosphorus requirement for Dwarf pink-shell layer hens is estimated to be 0.3% in a corn-soybean diet. With this level of phosphorus supplementation, calbindin and vitamin D receptor reached their highest expression.

关键词： Calbindin Laying hens Nonphytate phosphorus Sodium phosphate co-transporter Vitamin D receptor

Effects of Headgroups and Serum on Gene Transfection of Alkaline Amino Acid Based Cationic Lipids

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Chemical Research in Chinese Universities 2009年第1期25卷 69-71页

作者： LI Li YANG Yang nie Yu HE Bin GU zhong-wei National Engineering Research Center for Biomaterials Sichuan University Chengdu 610064 P. R. China

Three cationic lipids with lysylated（1）, histidylated（2）, and arginylated（3） headgroups and cholesterol hydrophobic moiety were synthesized. The average sizes of liposomes and lipoplexes were around 100 and 160 nm, respectively. The gene transfection efficiency of the three lipoplexes loaded with pGL3 or pORF-LacZ was compared on 293T cells in the presence or the absence of serum. The transfection efficiency of the three lipoplexes in a serum-free medium was 2 to 3-fold higher than that of dioleoyl-trimethylammonium propane（DOTAP）. In the presence of serum, however, most of the lipoplexes showed lower transfection activities; only lipoplex 3 retained its high transfection efficiency.

关键词： Cationic lipids Alkaline amino acids Serum Gene delivery Transfection efficiency

MAV/UAV task coalition phased-formation method

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Journal of Systems Engineering and Electronics 2019年第2期30卷 402-414页

作者： JIAO Zhiqiang YAO Peiyang ZHANG Jieyong zhong yun WANG Xun Information and Navigation College Air Force Engineering University

The formation of the manned aerial vehicle/unmanned aerial vehicle(MAV/UAV) task coalition is considered. To reduce the scale of the problem, the formation progress is divided into three phases. For the task clustering phase, the geographical position of tasks is taken into consideration and a cluster method is proposed. For the UAV allocation phase, the UAV requirement for both constrained and unconstrained resources is introduced, and a multi-objective optimal algorithm is proposed to solve the allocation problem. For the MAV allocation phase, the optimal model is firstly constructed and it is decomposed according to the ideal of greed to reduce the time complexity of the algorithm. Based on the above phases, the MAV/UAV task coalition formation method is proposed and the effectiveness and practicability are demonstrated by simulation examples.

关键词： task coalition formation task clustering unmanned aerial vehicle (UAV) allocation manned aerial vehicle (MAV) allocation

Development and application of microsatellite markers within transcription factors in flare tree peony(Paeonia rockii)based on next-generation and single-molecule long-read RNA-seq

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Journal of Integrative Agriculture 2021年第7期20卷 1832-1848页

作者： LIU Na CHENG Fang-yun GUO Xin zhong Yuan Beijing Advanced Innovation Center for Tree Breeding by Molecular Design/Beijing Key Laboratory of Ornamental Plants Germplasm Innovation&Molecular Breeding/National Engineering Research Center for Floriculture/Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education/Peony International Institute School of Landscape ArchitectureBeijing Forestry UniversityBeijing 100083P.R.China

Tree peonies native to China are a precious crop with ornamental,medicinal and edible oil properties,of which flare tree peony(Paeonia rockii)is one of the most significant germplasms in *** development and application of expressed sequence tag-simple sequence repeat(EST-SSR)markers are very valuable for genetic and breeding applications,but EST-SSR resources for the genus Paeonia are still *** this study,we first reported the development of SSRs within transcription factors(TFs)in *** based on next-generation sequencing(NGS)and single-molecule long-read sequencing(SMLRS).A total of 166 EST-SSRs containing six nucleotide repeat types were identified from 959 candidate TFs associated with yield,with an average of one SSR per 5.83 *** total,102(61.45%)pairs of primers produced amplification products in the two RNA-seq *** them,58(56.86%)pairs of primers from 18 gene families(AP2,b HLH,HSF,etc.)were identified to be polymorphic both in the parents of a linkage mapping population and in eight randomly selected accessions of ***,the 58 EST-SSRs indicated a high level of informativeness with PIC values ranging from 0.32 to 0.91(mean 0.70)after assessment in 37 tree peony *** studies indicated that the amplification ratio of the 58 pairs of primers ranged from 89.66 to 100%across seven species of *** addition,a genetic relationship study was performed in 62 *** analysis using the neighbour-joining(NJ)tree demonstrated that major clusters corresponded to the known pedigree *** together,these newly developed EST-SSRs have a potential use in the conservation of tree peony germplasm and marker-assisted selection(MAS)breeding.

关键词： flare tree peony(Paeonia rockii) EST-SSR markers polymorphism genetic diversity transferability genetic relationships

The Structure of Ammonium D,L-Tartrate

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Chinese Journal of Structural Chemistry 2001年第6期20卷 470-472页

作者： nie Jing-Jing XU Duan-Jun WU Jing-yun CHIANG Michael Yen-Nan Department of Chemistry Zhejiang University Department of Chemistry National Sun Yat-Sen University

The single crystals of the title compound NH4+C4H5O6- (C4H9NO6, Mr = 167.1) were obtained from a hot aqueous solution containing L-glutamine and D,L-tartaric acid in mole ratio1:1.5. The crystal belongs to monoclinic space group P21/c with a = 7.646(2), b = 7.804(2), c = 11.502(3)? ?= 102.26(2)o, V = 670.7(3)?, Z = 4, F(000) = 352, Dc = 1.655 ***-3, m(MoKa) = 0.16 mm-1, R = 0.035, wR = 0.094 for 1028 observed reflections (I>2s(I)). The enatiomeric anions of the tartrate with both (2S,3S)- and (2R,3R)-configuration co-exist in the unit cell. The carbon skeleton assumes a coplanar arrangement with a torsion angle of 181.5o. The three- dimensional H-bonding network exists in the crystal. While tartrate groups link each other by H-bonds between carboxyl and hydroxyl groups, the ammonium cations insert between the tartrate groups to form a sandwich-like crystal structure.

关键词： crystal structure ammonium tartrate H-bonding hydrolysis glutamine

Analysis and Design of Scaling Optimal GPM-PID Control with Application to Liquid Level Control

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International Journal of Automation and computing 2016年第6期13卷 624-633页

作者： Zhuo-yun nie Rui-Juan Liu Fu-Jiang Jin Lai-Cheng Yan School of Information Science and Engineering National Huaqiao University School of Applied Mathematics Xiamen University of Technology

In this paper, a new analysis and design method for proportional-integrative-derivative （PID） tuning is proposed based on controller scaling analysis. Integral of time absolute error （ITAE） index is minimized for specified gain and phase margins （GPM） constraints, so that the transient performance and robustness are both satisfied. The requirements on gain and phase margins are ingeniously formulated by real part constraints （RPC） and imaginary part constraints （IPC）. This set of new constraints is simply related with three parameters and decoupling of the remaining four unknowns, including three controller parameters and the gain margin, in the nonlinear and coupled characteristic equation simultaneously. The formulas of the optimal GPM-PID are derived based on controller scaling analysis. Finally, this method is applied to liquid level control of coke fractionation tower, which demonstrate that the proposed method provides better disturbance rejection and robust tracking performance than some commonly used PID tuning methods.

关键词： Proportional-integrative-derivative (PID) controller controller scaling gain and phase margins integral of time absolute error (ITAE) liquid level control.