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Optimality conditions in set optimization employing higher-order radial derivatives

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Applied Mathematics(A Journal of Chinese Universities) 2017年第2期32卷 225-236页

作者： YU guo-lin Department of Mathematics Beifang University of NationalitiesYinchuan 750021China.

There are two approaches of defining the solutions of a set-valued optimization problem： vector criterion and set criterion. This note is devoted to higher-order optimality conditions using both criteria of solutions for a constrained set-valued optimization problem in terms of higher-order radial derivatives. In the case of vector criterion, some optimality conditions are derived for isolated （weak） minimizers. With set criterion, necessary and sufficient optimality conditions are established for minimal solutions relative to lower set-order relation.

关键词： higher-order radial derivative optimality conditions set-valued optimization vector criterion,set criterion.

Porous organic polymer nanotubes as luminescent probe for highly selective and sensitive detection of Fe^(3+)

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Science China Chemistry 2017年第8期60卷 1090-1097页

作者： Meng Wang lin guo Dapeng Cao State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologBeLling 100029China

Two porous organic polymer nanotubes(PNT-2 and PNT-3) were synthesized via Ni-catalyzed Yamamoto reaction, using2,4,6-tris-(4-bromo-phenyl)-[1,3,5]-triazine(TBT) as one monomer, and 2,7-dibromopyrene(DBP) or 1,3,6,8-tetrabromopyrene(TBP) as another monomer. The scanning electron microscope(SEM) images show that both PNT-2 and PNT-3 possess clear hollow tube structures. Luminescent measurements indicate that both PNT-2 and PNT-3 can serve as luminescent probe for highly selective and sensitive detection of Fe^(3+) by luminescent quenching effect. Absorption competition quenching(ACQ) mechanism is also proposed to explain luminescent quenching behavior, i.e., the overlap of the UV-spectra between Fe^(3+) and PNTs causes the energy competition, and therefore leads to luminescent quenching. Moreover, both PNT-2 and PNT-3 still show high selectivity and sensitivity for sensing Fe^(3+) in 10% ethanol aqueous solution, which means that the two porous PNTs are promising candidates as luminescent probes for detecting Fe^(3+) in practical applications.

关键词： porous organic polymers polymer nanotubes luminescent sensors adsorption spectrum metal ions

Perturbation of Spectra for a Class of 2×2 Operator Matrices

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Acta Mathematicae Applicatae Sinica 2012年第4期28卷 711-720页

作者： ALATANCANG guo-lin HOU guo-jun HAI School of Mathematical Sciences Inner Mongolia University

In this paper, we study the perturbation of spectra for 2 ×2 operator matrices such as Mx ={A0 XB） AC and Mz = （Az CB） on the Hilbert space H K and the sets……

关键词： operator matrices point spectrum residual spectrum continuous spectrum perturbation ofspectrum

Proof of Six-Wave Resonance Conditions of Ocean Surface Gravity Waves in Deep Water

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China Ocean Engineering 2019年第6期33卷 734-738页

作者： lin guo-bin HUANG Hu Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering Science Shanghai University

A necessary big step up in the modern water wave theories and their widespread application in ocean engineering is how to obtain 6-wave resonance conditions and to prove it. In the light of the existing forms and characteristics of 3-wave, 4-wave and 5-wave resonance conditions, the 6-wave resonance conditions are proposed and proved for currently a maximum wave-wave resonance interactions of the ocean surface gravity waves in deep water, which will be indispensable to both the Kolmogorov spectrum of the corresponding universal wave turbulence and a synthetic 4-5-6-wave resonant model for the ocean surface gravity waves.

关键词： 6-wave resonance conditions proof ocean surface gravity waves in deep water wave turbulence

Effect of surfactant structure on catalysis of microemulsion for photoisomerization of trans-stilbene

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Chinese Chemical Letters 2007年第10期18卷 1265-1268页

作者： Xia guo ling lin Rong guo School of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 China

In this study, the photoisomerization of trans-stilbene was carded out in water in oil （W/O） microemulsions by using sodium dodecyl sulfate （SDS）, dodecyl trimethyl ammonium bromide （DTAB） and cetyl trimethyl ammonium bromide （CTAB） as surfactant, respectively. The catalytic effect of microemulsion on this reaction is closely related to the structure of surfactant. When there is no photosensitizer 9,10-dicyanoanthracene （DCA）, the surfactant with shorter hydrophobic chain is preferred, while in the presence of DCA, the surfactant with anionic polar group is preferred.

关键词： Microemulsion Photoisomerization trans-Sfilbcne

Construction of controllable size silver nanoparticles immobilized on nanofibers of chitin microspheres via green pathway

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Nano Research 2016年第7期9卷 2149-2161页

作者： lin guo Bo Duan lina Zhang College of Chemistry & Molecule Sciences Wuhan University Wuhan 430072 China State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

In the present work, nanofibrous chitin microsphere （NCM） was prepared via sol-gel transition from a chitin solution dissolved in a NaOH/urea aqueous system at low temperatures. Ag nanoparticles （AgNPs） were synthesized via an in situ reduction of silver nitrate using trisodium citrate dehydrate and were immobilized on chitin nanofibers to obtain composite microspheres that consist of nanofibers and AgNPs （NCM-Ag）. The size of AgNPs could be controlled in the range of 10 to 70 nm, depending on the concentration of AgNO3. X-ray photoelectron spectroscopy （XPS） and Fourier transform infrared （FT-IR） analyses showed that the chitin nanofibers have a strong affinity toward AgNPs, resulting from the interaction between the acetamino group of chitin and the AgNPs. The NCM-Ag exhibited a perfect nanoporous structure and high surface area, as well as high stability in organic solvents. Moreover, in the catalytic epoxidation of olefin （particularly, the conversion of styrene to styrene epoxide）, NCM-Ag exhibited an excellent selectivity of up to 90%. Converting chitin powder into chitin microspheres using an environmentally friendly technique is a green process, which is beneficial for the large-scale synthesis of industrial products. More importantly, this work provides a green synthetic pathway for the construction of size-controlled noble metal nanoparticles immobilized on nanofiber support, which have a wide range of potential applications.

关键词： chitin microsphere nanofibers immobilization of silvernanoparticles selective epoxidation controllable nano-size

On the Upper Bounds of the Numbers of Perfect Matchings in Graphs with Given Parameters

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Acta Mathematicae Applicatae Sinica 2007年第1期23卷 155-160页

作者： Hong lin Xiao-feng guo School of Mathematical Sciences Xiamen University Xiamen 361005 China

Let φ（G）, κ（G）, α（G）, χ（G）, cl（G）, diam（G） denote the number of perfect matchings, connectivity, independence number, chromatic number, clique number and diameter of a graph G, respectively. In this note, by constructing some extremal graphs, the following extremal problems are solved： 1. max {φ（G）：｜V（G）｜ = 2n, κ（G）≤ k} = k[（2n - 3）!!], 2. max{φ（G）：｜V（G）｜ = 2n,α（G） ≥ k} =[∏ i=0^k-1 （2n - k-i]（2n - 2k - 1）!!], 3. max{φ（G）：｜V（G）｜=2n, χ（G） ≤ k} =φ（Tk,2n） Tk,2n is the Turán graph, that is a complete k-partitc graph on 2n vertices in which all parts are as equal in size as possible, 4. max{φ（G）：｜V（G）｜ = 2n, cl（G） = 2} = n!, 5. max{φ（G）：｜V（G）｜ = 2n, diam（G） ≥〉 2} = （2n - 2）（2n - 3）[（2n - 5）!!], max{φ（G）：｜V（G）｜ = 2n, diam（G） ≥ 3} = （n - 1）^2[（2n - 5）!!].

关键词： Perfect matching connectivity chromatic number clique number diameter

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搭接长度等对Ⅱ型APC接头拉伸性能的影响

哈尔滨工业大学学报 2025年第1期57卷 128-139页

作者：余琼敖晟瑞唐子鸣郭霖谢青海张志陈振海同济大学土木工程学院上海200092 山西建筑工程集团有限公司太原030006 山西二建集团有限公司太原030013

为研究搭接长度和钢筋直径对Ⅱ型APC接头力学性能的影响,对63个该接头进行单向拉伸试验,分析了接头破坏模式、极限承载力、延性和黏结应力等。结果表明:钢筋直径相同时,随搭接长度增加,平均黏结应力降低,试件强度、延性、最大力总伸长... 详细信息

为研究搭接长度和钢筋直径对Ⅱ型APC接头力学性能的影响,对63个该接头进行单向拉伸试验,分析了接头破坏模式、极限承载力、延性和黏结应力等。结果表明:钢筋直径相同时,随搭接长度增加,平均黏结应力降低,试件强度、延性、最大力总伸长率明显提高,残余变形整体呈下降趋势;钢筋拉断破坏试件强度、延性、最大力总伸长率和残余变形满足规范要求;加载过程中,套筒中部截面短边纵向和长边环向始终受拉;极限荷载下,随搭接长度增加,套筒中部截面短边侧环向压应变先转变为拉应变再向压应变发展,长边侧纵向压应变转变为拉应变;相对搭接长度相同时,极限承载力随钢筋直径增加而提高;提出的极限黏结强度及临界搭接长度计算公式与试验值吻合较好,可为实际工程应用提供参考。单拉工况下,钢筋直径不大于18 mm时,建议接头搭接长度大于12 d。

关键词： Ⅱ型APC接头拉伸性能搭接长度黏结强度

Quantum coherence and ground-state phase transition in a four-chain Bose–Hubbard model

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Communications in Theoretical Physics 2021年第8期73卷 182-188页

作者： Ji-guo Wang lin-Qi guo Ya-Fei Song Department of Mathematics and Physics Shijiazhuang TieDao UniversityShijiazhuang 050043China Institute of Applied Physics Shijiazhuang TieDao UniversityShijiazhuang 050043China

We study the quantum coherence and ground-state phase transition of a four-chain Bose–Hubbard model with the long-range interaction. In a special four-chain Bose–Hubbard model,i.e., each chain only has one optical potential, four types of the ground-state phases are discovered. The effects of the disorder, the on-site interaction and the long-range interaction on the quantum coherence are studied. For the system without the long-range interaction, the quantum coherence changes from one periodic oscillation to two periodic oscillations as the onsite interaction increases. By considering the long-range interaction, the quantum coherence goes back to one periodic oscillation again. The on-site interaction itself suppresses the quantum coherence, both the on-site interaction and long-range interaction together enhance the quantum coherence with the weak disorder. If the disorder strength is increased beyond a critical value,they start to suppress the quantum coherence. In a regular four-chain Bose–Hubbard model, i.e.,each chain has many optical potentials, the ground-state phase transitions are obtained by using the cluster Gutzwiller mean-field method. Exotic ground-state phases are found, i.e., superfluid phase, integer Mott insulator phase, supersolid phase and loophole insulator phase. The combination of the loophole insulator phase and the supersolid phase expands the lobes with the half-integer filling per site for the small ratio β = t_(‖)/t_(⊥).

关键词： Bose-Hubbard model quantum coherence ground-state phase transition