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Journal of the Operations Research Society of China 2023年第4期11卷 857-874页

作者： Le Luo Ying-hui Tang Miao-Miao Yu wen-qing Wu School of Mathematical Sciences Sichuan Normal UniversityChengdu610068SichuanChina Nanchong Vocational and Technical College Nanchong637000JiangsuChina Visual Computing and Virtual Reality Key Laboratory of Sichuan Province Sichuan Normal UniversityChengdu610068SichuanChina

Based on the number of customers and the server’s workload,this paper proposes a modified Min(N,D)-policy and discusses an M/G/1 queueing model with delayed randomized multiple vacations under such a *** the well-known stochastic decomposition property of the steady-state queue size,the probability generating function of the steady-state queue length distribution is ***,the explicit expressions of the expected queue length and the additional queue length distribution are derived by some algebraic ***,employing the renewal reward theorem,the explicit expression of the long-run expected cost per unit time is ***,we analyze the optimal policy for economizing the expected cost and compare the optimal Min(N,D)-policy with the optimal N-policy and the optimal D-policy by using numerical examples.

关键词： M/G/1 queue Modified Min(N,D)-policy Randomized multiple vacations Queue length generating function Optimal joint control policy

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军曹鱼幼鱼对吡哆醇的需要量

水产学报 2010年第2期34卷 307-314页

作者：刘凯麦康森艾庆辉张文兵王小洁肖林栋任鸣春中国海洋大学教育部海水养殖重点实验室

以初始体重(3.23±0.06)g的军曹鱼为研究对象,以酪蛋白(不含维生素)、明胶、鱼肉浓缩蛋白为蛋白源,在基础饲料中分别添加0、2、4、8、16和32mgPN/kg,配制出6种实验饲料,使饲料中吡哆醇的水平分别达到0.22、1.89、3.87、7.54、14.75和29.... 详细信息

以初始体重(3.23±0.06)g的军曹鱼为研究对象,以酪蛋白(不含维生素)、明胶、鱼肉浓缩蛋白为蛋白源,在基础饲料中分别添加0、2、4、8、16和32mgPN/kg,配制出6种实验饲料,使饲料中吡哆醇的水平分别达到0.22、1.89、3.87、7.54、14.75和29.88mgPN/kg,研究军曹鱼对吡哆醇的需要量。养殖实验在室内流水系统中(250L)进行,每个处理设3个重复,每个重复放养军曹鱼25尾。养殖实验过程中,海水盐度为30～34,水温28～32℃,溶氧>7mg/L,养殖实验持续9周。实验结果显示,在0.22～3.87mgPN/kg水平范围内,随着饲料中吡哆醇含量的升高,实验鱼特定生长率显著升高,当饲料吡哆醇水平达到或高于3.87mg/kg时,各饲料组实验鱼的特定生长率(2.68～2.71%/d)无显著差异,而都显著高于0.22和1.89mg/kg饲料组的特定生长率(1.17～2.06%/d)P<0.05)。军曹鱼肝脏吡哆醇含量、吡哆醛含量、谷丙转氨酶活力、谷草转氨酶活力均与特定生长率有相似的变化趋势,即在3.87mg/kg饲料组接近或者达到最大值,在达到或超过3.87mg/kg时达到或近似达到一平台。根据实验结果,以军曹鱼幼鱼特定生长率和谷丙转氨酶活力、谷草转氨酶活力分别拟合折线模型,得到军曹鱼幼鱼对饲料中吡哆醇的需要量为3.09～3.26mg/kg饲料。

关键词：军曹鱼吡哆醇需要量鱼类营养

Electrochemical Synthesis and Research of Two Polymers Composed of Alternate Carbazole and Thiophene Units

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Chinese Journal of Chemical Physics 2015年第5期28卷 -页

作者： qing Cheng qing-zhen wen College of Science Naval University of Engineering Wuhan 430033 china

Two organic conjugated molecules composed of central carbazole and bithiophene groups were prepared via the Stille coupling reaction, conductive polymers were prepared by electrochemical method. Structure and photoelectric research of polymers were investigated. 1H NMR and 13C NMR of molecules were consistent with the theorical results, FT-IR showed electrochemical polymeric site were β-position of thiophene units. The smooth morphology and distributed holes were beneficial to improve the electrical conductivity by SEM. When applied voltage was from ?0.1 V to 1.2 V, both of the polymer films P1 and P2 showed good electrochromic performances. Compared with P1, P2 had better electrochemical stability and thermal stability due to the better coplanarity by repeated cyclic voltammograms and TGA. The P2 was a promising material in the electrochemical field, meanwhile, it showed that the monomer structure had greatly impact on the performance of polymer.

关键词： Stille reaction Cyclic voltammetry Electrochemistry polymerization Spectroelectrochemistry

On Performance Gauge of Average Multi-Cue Multi-Choice Decision Making:A Converse Lyapunov Approach

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IEEE/CAA Journal of Automatica Sinica 2021年第1期8卷 136-147页

作者： Mehdi Firouznia qing hui the Department of Electrical and Biomedical Engineering University of VermontBurlingtonVT 05405 USA the Department of Electrical and Computer Engineering University of Nebraska-LincolnLincolnNE 68588 USA

Motivated by the converse Lyapunov technique for investigating converse results of semistable switched systems in control theory,this paper utilizes a constructive induction method to identify a cost function for performance gauge of an average,multi-cue multi-choice(MCMC),cognitive decision making model over a switching time *** shows that such a constructive cost function can be evaluated through an abstract energy called Lyapunov function at initial ***,the performance gauge problem for the average MCMC model becomes the issue of finding such a Lyapunov function,leading to a possible way for designing corresponding computational algorithms via iterative methods such as adaptive dynamic *** order to reach this goal,a series of technical results are presented for the construction of such a Lyapunov function and its mathematical properties are discussed in ***,a major result of guaranteeing the existence of such a Lyapunov function is rigorously proved.

关键词： Cognitive modeling decision making Lyapunov function multi-cue multi-choice tasks performance gauge

Combined effects of ultrasonic vibration and FeCoNiCrCu coating on interfacial microstructure and mechanical properties of Al/Mg bimetal by compound casting

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China Foundry 2024年第5期21卷 588-598页

作者： Yuan-cai Xu wen-ming Jiang qing-qing Li Ling-hui Yu Xiao-peng Yu Zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

In this work,a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy(HEA)coating was used to prepared Al/Mg bimetal through the lost foam compound *** effects of composite treatment involving ultrasonic vibration and HEA coating on interfacial microstructure and mechanical properties of Al/Mg bimetal were *** demonstrate that the interface thickness of the Al/Mg bimetal with composite treatment significantly decreases to only 26.99%of the thickness observed in the untreated Al/Mg *** HEA coating hinders the diffusion between Al and Mg,resulting the significant reduction in Al/Mg intermetallic compounds in the *** Al/Mg bimetal interface with composite treatment is composed of Al_(3)Mg_(2)and Mg_(2)Si/AlxFeCoNiCrCu+FeCoNiCrCu/δ-Mg+Al_(12)Mg_(17)eutectic *** interface resulting from the composite treatment has a lower hardness than that without *** acoustic cavitation and acoustic streaming effects generated by ultrasonic vibration promote the diffusion of Al elements within the HEA coating,resulting in a significant improvement in the metallurgical bonding quality on the Mg *** fracture position shifts from the Mg side of the Al/Mg bimetal only with HEA coating to the Al side with composite *** shear strength of the Al/Mg bimetal increases from 32.16 MPa without treatment to 63.44 MPa with ultrasonic vibration and HEA coating,increasing by 97.26%.

关键词： ultrasonic vibration FeCoNiCrCu HEA coating Al/Mg bimetal interfacial microstructure shear strength compound casting

Identification of Molecular Markers for a Aphid Resistance Gene in Sorghum and Selective Efficiency Using These Markers

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Journal of Integrative Agriculture 2012年第7期11卷 1086-1092页

作者： CHANG Jin-hua CUI Jiang-hui XUE Wei ZHANG qing-wen College of Agriculture and Biotechnology China Agricultural University Beijing 100096 P.R.China College of Agriculture Agricultural University ofHebei Baoding 071001 P.R.China Student Employment Guidance Center Baoding Vocational and Technical College Baoding 071001 P.R.China

In this study, an F2 segregated population obtained by hybridization between the aphid-sensitive sorghum strain Qiansan and aphid-resistant cultivar Henong 16 was used to establish an aphid-resistant pool and an aphid-sensitive pool. 192 pairs of AFLP （amplified fragment length polymorphism） marker primers were screened in these pools using BSA （bulked segregant analysis）. Three pairs of EcoR I-CTG/Mse I-CCT, EcoR I-CTG/Mse I-CAT, and EcoR I-AGT/Mse I-CCC showed linkage with aphis resistance. EcoR I-CTG/Mse I-CCT-475, EcoR I-CTG/Mse I-CAT-390, and EcoR I-AGT/Mse I-CCC- 350 （E42/M52-350） were mapped within 6, 10, and 13 cM distances with the aphid-resistant gene by using Mapmaker 3.0 software. The bands amplified by EcoR I-CTG/Mse I-CCT-475 and EcoR I-CTG/Mse I-CAT-390 were extracted, cloned, and sequenced. Specific primers of SCAR （sequence characterized amplified regions） were then designed from these bands. A specific band of 300 bp was amplified by a pair of SCAR primers designed based on the sequence obtained from the EcoR I-CTG/Mse I-CAT-390 marker. The SCAR marker was named SCAS0. The marker was used to detect the F2, BC1, and F2：3 populations. The selective efficiency was 86.8, 91.1, and 86.3% in the BC1, F2, and F2：3 populations, respectively. The average selective efficiency was 88.2%.

关键词： sorghum bicolor aphid resistance gene molecular marker SCAR molecular assistant selection

Probing intermolecular interactions of ZnO-nanoparticle-reinforced molten energetic material

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Rare Metals 2022年第9期41卷 3180-3185页

作者： qing Ma Shu-Ming Wang Mao-Ping wen Bao-hui Zheng Heng-Jian Huang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang621900China Analysis and Testing Center Southwest University of Science and TechnologyMianyang621900China

In this work,metal oxide nanoparticle ZnO was employed for the reinforcement of *** electronic microscopy(SEM)was used to study the microstructure on the fractured surface of TNT/nano-ZnO,and ultraviolet-visible(UV-Vis)spectroscopy was utilized for structure ***,to understand the reinforcing mechanism between ZnO and TNT,quantum chemistry and molecular dynamics simulation were undertaken to investigate the intermolecular interaction and mechanical *** is concluded that with 2.85 wt%ZnO nanoparticle addition,the amount of voids and defects decreases with the increase in bulk and shear *** modified TNT/ZnO composite has high heat of formation,negative oxygen balance,and good detonation properties,which is expected to be a candidate for high-energy blended explosives.

关键词： 2 4 6-Trinitrotoluene Zinc oxide Intermolecular interaction Molecular dynamics simulation

Rhodium-catalyzed enantioselective annulation of N-phenoxyacetamides with 1,3-dienes

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Science China Chemistry 2023年第10期66卷 2842-2846页

作者： hui Yang Zi-Qi Yang Su-Zhen Zhang wen-wen Zhang qing Gu Shu-Li You State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Chiral dihydrobenzofuran is a valuable synthetic fragment in both medicinal and organic *** rhodium(Ⅲ)-catalyzed chemoselective and enantioselective C-H functionalization/[3+2]annulation of N-phenoxyacetamides with 1,3-dienes is *** the presence of 5 mol%Cp Rh complex,various chiral dihydrobenzofurans were synthesized in up to 79%yield and 98%*** reaction proceeds under mild conditions with excellent functional group compatibility.

关键词： asymmetric catalysis C-H functionalization rhodium catalysis chiral dihydrobenzofuran

Transition-layer of coreerim structures andβ→a transformation in SiC ceramics

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Journal of Materiomics 2023年第2期9卷 299-309页

作者： qing-qing Shao hui Gu Materials Genome Institute School of Materials Science and EngineeringShanghai UniversityShanghai200444China

Similar to Si_(3)N_(4)ceramics,β→a phase transformation in SiC ceramics plays a key role in tailoring the microstructures thus optimizing related *** microstructures are dominated with the core erim structures by AlN-solution,and by EBSD analysis,a-lamellae were revealed as stacking-faults(SF)and twin-boundaries(TB)in b-grains,co-existing with the coreerim structures asα/β→α’/β’transformation by *** structural transformation can proceed much further by gas-pressuresintering than hot-pressing with only RE2O3 agents,while the latter retain a high-density of SF/TB in the metastable b-SiC *** high-angle secondary-electron imaging,nanoscale transition-layer(TL)was observed as an inter-phase to fully separate the core and rim,which is created by a transitory equilibrium in the solutionereprecipitation *** enrichment of AlN or RE in TL demonstrates their segregation to core surface until reaching the super-saturation and before the growth of *** higher AlN or RE solution and after sintering,a shear stress can develop from TL contour to drive the expansion of SF/TB in Martensitic transition,especially under an external isotropic *** combinations ofβ→a transformation,coreerim structures and viscous liquid-phase enable the comprehensive assessment of sintering-microstructure-property-performance relationship of SiC ceramics,as demonstrated for their creep behaviors and fracture toughness.

关键词： SiC ceramics Coreerim structures Transition-layer Martensitic transition Creep behaviors

As-cast microstructure of Al-Zn-Mg-Cu-Zr alloy containing trace amount of Sc

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Rare Metals 2019年第4期38卷 343-349页

作者： Yu Wang Bai-qing Xiong Zhi-hui Li Shu-hui Huang Kai wen Xi-Wu Li Yong-An Zhang State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals

It has been reported that the element scandium (Sc) is the most effective modificator which can significantly refine the grain size,prohibit recrystallization process and increase the *** trace of Sc in 7000 series aluminum alloys is considered to be an effective way to modify its microstructure and promote mechanical *** order to study the effect of Sc element on ascast microstructure of Al-Zn-Mg-Cu-Zr alloy,ingots containing different amounts of Sc were prepared by ferrous-mold *** were characterized by means of differential scanning calorimeter (DSC),X-ray diffraction (XRD),optical microscope (OM) and scanning electrical microscope (SEM).The results indicate that when the Sc level exceeds a critical concentration,A13(Sc,Zr) primary phase would form in the melt and act as an efficient nucleant,resulting in very refined grain and an equiaxed grain *** element reduces the number of eutectic phases formed during solidification,coupled with an increase in the concentration of major alloying elements retained in the *** behavior suggests possible benefits in improving the integrated properties of terminal products.

关键词： Scandium Aluminum alloy As-cast Microstructure Nucleant