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Experimental and numerical study on ignition and combustion characteristics of boron-magnesium composite powders

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Particuology 2024年第1期84卷 12-29页

作者： Shuyuan liu Luyang Han hongmei liu Yingkai Song Linlin liu Songqi Hu Science and Technology on Combustion Internal Flow and Thermo-Structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China School of Mechanical Engineering and Rail Transit Changzhou UniversityChangzhou213164China Shanghai Institute of Space Propulsion Shanghai201112China Shanghai Engineering Research Center of Space Engine Shanghai201112China

A high-pressure laser ignition and combustion system with adjustable oxidizer gas atmosphere is established to investigate the ignition and combustion characteristics of boron-magnesium(BM)com-posite *** ignition and combustion model of BM powders is established and validated in the present *** results show that increasing water content,O_(2) content and Mg content all result in shorter ignition delay time of BM powders,among which the effect of water content is the most ***,ignition delay time increases as pressure *** combustion time decreases with increasing Mg content and ambient pressure but increases with water *** the increase of O_(2) content,combustion time of BM powders first increases and then decreases,which means a critical O_(2) content exists above which combustion time *** results show that there exists a trade-off between ignition and combustion performance of BM composite powders.

关键词： Boron magnesium powder Laser ignition Ignition and combustion model Reaction mechanism Numerical model

Fault-Tolerant Cycles Embedding in Folded Hypercubes

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Wuhan University Journal of Natural Sciences 2016年第3期21卷 191-198页

作者： liu hongmei TANG Maozeng College of Science China Three Gorges University

The generalized conditional fault-tolerant embedding is investigated, in which the n-dimensional folded hypercube networks （denoted by FQn） acts as the host graph, and the longest fault-free cycle represents the guest graph. Under the conditions looser than that of previous works, it is shown that FQn has a cycle with length at least 2n -21F, I when the number of faulty vertices and non-critical edges is at most 2n-4; where ｜Fv｜ is the number of faulty vertices. It provides further theoretical evidence for the fact that FQn has excellent node-fault-tolerance and edge-fault-tolerance when used as a topology of large scale computer networks.

关键词： fault tolerance cycle embedding folded hypercube networks

ELIMINATION AND IDENTITIES WITH THE INTEGRAL SIGN

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Journal of Systems Science & Complexity 2006年第4期19卷 470-477页

作者： hongmei liu Tianming WANG Department of Applied Mathematics Dalian University of Technology Dalian 116024 China. Department of Applied Mathematics Dalian University of Technology Dalian 116024 Department of Mathematics Hainan Normal University Haikou 571158 China.

In this paper, we aim at using the elimination in Weyl algebra to give an algorithm for proving the identities with integral sign. Then, we test several examples that have been proved by D. Zeilberger.

关键词： Algorithm proof elimination identities with integral sign.

Novel dual-band antenna for multi-mode GNSS applications

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Journal of Systems Engineering and Electronics 2015年第1期26卷 19-25页

作者： hongmei liu Shaojun Fang Zhongbao Wang School of Information Science and Technology Dalian Maritime University

A novel dual-band antenna is proposed for mitigating the multi-path interference in the global navigation satellite system（GNSS） applications. The radiation patches consist of a shortedannular-ring reduced-surface-wave（SAR-RSW） element and an inverted-shorted-annular-ring reduced-surface-wave（ISAR-RSW）element. One key feature of the design is the proximity-coupled probe feeds to increase impedance bandwidth. The other is the defected ground structure band rejection filters to suppress the interaction effect between the SAR-RSW and the ISAR-RSW elements. In addition, trans-directional couplers are used to obtain tight coupling. Measurement results indicate that the antenna has a larger than 10 d B return loss bandwidth and a less than 3 d B axial-ratio（AR） bandwidth in the range of（1.164 – 1.255） GHz and（1.552 – 1.610） GHz. The gain of the passive antenna in the whole operating band is more than 7 d Bi.

关键词： active antenna dual-band antenna multi-path interference

More Asymptotic Expansions for the Harmonic Numbers

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Journal of Mathematical Research with Applications 2020年第3期40卷 297-304页

作者： hongmei liu School of Science Dalian Minzu University

In this paper, by exponential complete Bell polynomials, we establish a(general)harmonic number asymptotic expansion, and give the corresponding recurrence of the coefficient sequence in the expansion. By the methods of the generating functions and summation transformations, we also present an explicit expression for the coefficient sequence of the ***, we establish two(general) lacunary harmonic number asymptotic expansions, which contain only even or odd power terms in the logarithmic term.

关键词： asymptotic expansions harmonic numbers Bell polynomials

Characteristics of phytoliths in Leymus chinensis from different habitats on the Songnen Plain in Northeast China and their environmental implications

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Science China Earth Sciences 2010年第7期53卷 984-992页

作者： JIE DongMei liu ZhaoYang SHI LianXuan liu hongmei GE Yong College of Urban and Environmental Science Northeast Normal UniversityChangchun 130024China School of Life Sciences Northeast Normal UniversityChangchun 130024China

The characteristics of phytoliths in Leymus chinensis leaves from five different pH-value habitats from Songnen Plain in China were analyzed to reveal their environmental implications and possible use for quantitative reconstruction of the paleoenvironment. The phytoliths in leaves of L. chinensis from the five habitats showed a non-linear correlation with soil pH. The main types of phytoliths from the different habitats were exactly the same, including silicified stomata, hat-shaped, lanceolate, elongated, multilateral-plate, and tooth-shaped. However, there were significant differences in the contents of each shape of phytoliths among the five habitats. The amount and the volume of weakly tooth-shaped, lanceolate phytoliths and silicified stomata increased with increased pH, while the total amount of phytoliths was reduced. In addition, there were different types of phytoliths in the L. chinensis leaves from the five habitats of different pH, suggesting that the types of phytoliths were controlled, at least in part, by soil pH. The changes of size and percentage of phytoliths were most remarkable at pH 10.15–10.18, indicating that this is the highest pH value that L. chinensis can tolerate.

关键词： phytolith pH habitat Leymus chinensis Songnen Plain environmental implications

A Breakthrough in Understanding the Rapid Antidepressant Effect of Ketamine Based on Structural Analysis

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Neuroscience Bulletin 2022年第2期38卷 229-231页

作者： hongmei liu Xiaohui Wu Jun Chen Yiru Fang Clinical Research Center Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghai 200030China CAS Center for Excellence in Brain Science and Intelligence Technology Shanghai 200031China Shanghai Key Laboratory of Psychotic disorders Shanghai 201108China

Major depressive disorder(MDD)is one of the most common and serious mental *** overall 12-month prevalence rate is〜6%,while the lifetime risk increases about twofold(15%-18%),which means almost one in five people will experience at least one depressive episode during their lifetime[1].MDD is characterized by sad emotion accompanied by anhedonia,lack of energy or appetite,sleep disturbance,and low *** severe cases,suicidal ideation/attemp^ehavior or self-injurious behavior may occur,which seriously affects patients'daily life and social *** 2010,MDD was listed as the second greatest disease burden in the world,and is expected to rank first by 2030[2].

关键词： function lifetime listed

Design principles in mechanically adaptable biomaterials for repairing annulus fibrosus rupture:A review

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Bioactive Materials 2024年第1期31卷 422-439页

作者： Dan Zhou hongmei liu Zhaomin Zheng Decheng Wu Guangdong Provincial Key Laboratory of Advanced Biomaterials Department of Biomedical EngineeringSouthern University of Science and TechnologyShenzhen518055China Department of Spine Surgery The First Affiliated HospitalSun Yat-Sen UniversityGuangzhou510080China Pain Research Center Sun Yat-Sen UniversityGuangzhou 510080China

Annulus fibrosus(AF)plays a crucial role in the biomechanical loading of intervertebral disc(IVD).AF is difficult to self-heal when the annulus tears develop,because AF has a unique intricate structure and biologic milieu in *** engineering is promising for repairing AF rupture,but construction of suitable mechanical matching devices or scaffolds is still a grand *** deeply know the varied forces involved in the movement of the native annulus is highly beneficial for designing biomimetic scaffolds to recreate the AF *** this review,we overview six freedom degrees of forces and adhesion strength on AF ***,we summarize the mechanical modalities to simulate related forces on AF and to assess the characteristics of *** finally outline some current advanced techniques to develop mechanically adaptable biomaterials for AF rupture repair.

关键词： Annulus fibrosus Forces Mechanical matching High tough High adhesion

A New DGM(1,1)Model with a Grey Parameter and Its Application

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Journal of Systems Science and Information 2022年第3期10卷 297-308页

作者： Xin ZENG Jun liu Fuxiang liu hongmei liu School of Science China Three Gorges UniversityYichang 443002China Three Gorges Mathematical Research Center Yichang 443002China

In the DGM(1, 1) model modeling process, the influencing factors are uncertain. But the solution of DGM(1, 1) model with uncertain information is unique, which conflicts with the nonuniqueness principle of solution in grey theory. In view of this situation, this paper makes an in-depth analysis of the meaning of grey action quantity β_(2) in DGM(1, 1) model and regards β_(2) as an interval grey number. The maximum possibility whitenization value is given to estimate the kernel of grey number,and the typical possibility function is constructed to describe the possibility of grey number taking different values. A new DGM(1, 1) model with a grey parameter is then proposed, whose simulation results are interval grey numbers. The proposed model is compatible with the DGM(1, 1) model in model structure and simulation results. Finally, the practical example results show the applicability and effectiveness of the proposed model.

关键词： DGM(1,1)model non-uniqueness principle of solution interval grey number maximum possibility whitenization value