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FIRST　ORDER　QUASILINEAR　EQUATIONS　IN　SEVERAL　INDEPENDENT　VARIABLES　WITH　SINGULAR　INITIAL　DATA　L^p（P＜∞）

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Acta Mathematica Scientia 1996年第3期16卷 308-320页

作者：赵会江 Young scientist Laboratory of Mathematical Physics Wuhan Institute of Mathematical Sciences Academia Sinica Wuhan 430071 China

We study the existence problem for the equations of first order quasilinearequations in several inpendent variables with singular initial data Lp(P<∞). We the convergence of the Lp(P<∞) bounded approximating sequences generatedby the method of vanishing viscosity. The uniqueness of the generalized solutions whichcan be obtained by the method of vanishing viscosity is also obtained.

关键词： Singular initial data quasilinear equations global weak solutions

A Single-Fluorophore Multicolor Molecular Sensor That Visually Identifies Organic Anions Including Phosphates

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CCS Chemistry 2024年第3期6卷 774-782页

作者： Zezhou Zong Qi Zhang Da-Hui Qu Key Laboratory for Advanced Materials and Feringa Nobel Prize scientist Joint Research Center School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237

Developing fluorescent sensors for small-molecule phosphates offers opportunities in optically detecting biorelevant reactions and events.However,it remains elusive how to identify phosphates from other anions,such as carboxylates and sulfates,because current synthetic phosphate receptors lack selectivity.Here we report the construction of a multicolor fluorescent sensor that can identify phosphates from other analogous anions.The key design principle is to take advantage of the highly sensitive conformation-dependent emissive wavelength of diphenyl-9,14-dihydrodibenzo[a,c]phenazine fluorophores to sense the minor structural differences between phosphates and other anions,for example,sulfates and carboxylates.The effect of structural factors such as spacer length and urea versus thiourea has been investigated by comparing the optical properties and binding affinities with the phosphate receptors.This strategy provides a simple and robust fluorescent sensing solution to optically analyze small-molecule phosphates with antiinterference performance.

关键词： fluorescent sensors photoluminescence host-guest chemistry supramolecular chemistry noncovalent bonds

Possible effect of ENSO on annual sediment discharge of debris flows in the Jiangjia Ravine based on Morlet wavelet transforms

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International Journal of Sediment Research 2008年第3期23卷 267-274页

作者： J. H. ZHANG1, F. Q. WEI2, S. Z. LIU3, C. GAO41 Dr., Research scientist, Hainan Meteorological Science Institute, South-Sea Meteorology & Disaster Mitigation Research Key Laboratory, Haikou, China, No. 60 Haifu Road, Haikou, China, 2 Dr., Research scientist, 3 Research scientist,4 Dr.,Institute of Mountain Hazards and Environment, CAS, No. 9, Sec. 4, South Renmin Road, Chengdu, China Dr. Research Scientist Hainan Meteorological Science Institute South-Sea Meteorology & Disaster Mitigation Research Key Laboratory Haikou China No. 60 Haifu Road Haikou China Dr. Research Scientist Research scientist Institute of Mountain Hazards and Environment CAS No. 9 Sec. 4 South Renmin Road Chengdu China Dr. Research scientist Institute of Mountain Hazards and Environment CAS No. 9 Sec. 4 South Renmin Road Chengdu China

The multi-time-scale structures of an annual sediment discharge series of debris flow in the Jiangjia Ravine and the Southern Oscillation index are analysed using the method of Morlet wavelet transformations. The possible effects of El Nio episodes on the annual sediment discharge are discussed by comparing the period variations of ENSO and the discharge. The results show that the annual sediment discharge series of debris flow is related to El Nio episodes. Generally, the annual sediment discharge of debris flow is less than usual during an El Nino episode and debris flow is less active. On the contrary, the annual sediment discharge of debris flows is greater than usual during a La Nia episode and debris flows are more frequent. There is a relationship between the annual sediment discharges of debris flow in the Jiangjia Ravine and the summer Southern Oscillation index, with both having quasi-periodic variations of 2 and 5–6 years.

关键词： Debris flow ENSO Wavelet transform Periodic variation

Exploration of Strong Metal-Support Interaction in Heterogeneous Catalysts by in situ Transmission Electron Microscopy

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Chinese Journal of Chemistry 2024年第9期42卷 1004-1008页

作者： Yongjun Jiang Sheng Dai Key Laboratoryfor Advanced Materials and Feringa Nobel Prize scientist Joint Research Center Institute of Fine ChemicalsSchool of Chemistry&Molecular EngineeringEast China Universityof Science and TechnologyShanghai 200237China

The phenomenon of strong metal-support interaction(SMSI)observed in supported metal catalysts,usually accompanied by the formation of the encapsulation layer on metal nanoparticles,has attracted extensive research attention due to its significance in heterogeneous catalysis.Notably,great progress has been made in recent years in investigating SMSI by in situ transmission electron microscopy(TEM),along with an enhanced comprehension of the underlying mechanisms governing SMSI formation.This emerging topic summarizes recent progress utilizing in situ TEM to study the interaction between metal and support and the relationship between the structure and performance of the supported catalyst under reaction conditions.A brief perspective about the use of in situ TEM for further study of SMSI is also presented,showing prospects in this field that will stimulate further upsurging research in promoting the catalytic efficiency of supported catalysts.

关键词： Heterogeneous catalysis In situ TEM Strong metal-support interaction Structure changes Interfaces Structural evolution

Long-term olfactory loss post-COVID-19:Pathobiology and potential therapeutic strategies

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 148-155页

作者： Sarah Kim John B.Finlay Tiffany Ko Bradley J.Goldstein Department of Head and Neck Surgery&Communication Sciences Duke UniversityDurhamNorth CarolinaUSA Medical scientist Training Program Duke UniversityDurhamNorth CarolinaUSA Department of Neurobiology Duke UniversityDurhamNorth CarolinaUSA

An acute loss of smell emerged as a striking symptom present in roughly half of the people infected with the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus in the early phases of the COVID-19 pandemic.In most COVID-19 patients,olfaction recovers over the course of a few weeks.However,a lasting partial or complete loss of smell,often associated with distorted olfactory perceptions termed parosmia,has emerged as a widespread problem impacting at least 5%-10%of those who experience anosmia due to COVID-19.Our inability to offer effective therapies to this hyposmic or anosmic population,comprising millions of patients,highlights an enormous unmet need for the medical system.Here,we summarize the current understanding of the pathobiology causing acute olfactory loss due to SARS-CoV-2 infection,focusing on how the virus interacts with the peripheral olfactory system,a major site of viral infection.We also explore the problem of long-COVID olfactory dysfunction,which may accompany other persistent systemic disorders collectively termed postacute sequelae of COVID-19.Specifically,we discuss an emerging model focused on unresolved immune cell activity driving ongoing dysfunction.Finally,we review current and future therapeutic approaches aimed at restoring olfactory function.

关键词： hyposmia inflammation long-COVID parosmia

H^1 SOLUTIONS FOR A CLASS OF SEMILINEAR PARABOLIC SYSTEMS

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Acta Mathematica Scientia 1997年第1期17卷 91-96页

作者：严国政 Young scientist Laboratory of Math. Phys. Inst. of Math. Sci. Academia Sinica Wuhan 430071 China

In this paper, we consider the Cauchy problem of a class of semilinear parabolic system. Firstly, we obtain the local existence of solutions of (1.1),(1.2) in H-1(R(1)), and then we prove the global existence of the s... 详细信息

关键词： parabolic system a priori estimate global solution

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Acta Mathematica Scientia 1997年第2期17卷 180-189页

作者：严国政 Young scientist Laboratory of Math. Phys. Wuhan Inst. of Math. Sci. Academia Sinica Wuhan 430071 China

In this paper, we investigate the following partial differential equation, ut , where a > 0 and p> 1. When n(p-1)/2 > 1 andp > 3, we obtained a nontrivial non-negative global solution. Furthermore, on Sobolev space W1,s(W2,s) with s > 1. a nonuniqueness result is established which shows that there exists a positive solution u(t,x) with u(t,x)→0 as t→0 in W1,s(W2,s). On the other hand, our result can be regarded as a generalization of conclusion of Haraux, A.and Weissler, F.B. in [5].

关键词： Existence and asymptotic behavior self-similar solution non-uniqueness

POSITIVE SOLUTIONS FOR NONHOMOGENEOUS ELLIPTIC EQUATIONSWITH CRITICAL GROWTH ON R^(2)

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Acta Mathematica Scientia 1998年第2期18卷 124-138页

作者：周焕松 The Young scientist Labortary of Mathematical Physics Wuhan' Institute of Physics and Mathematics Academia Sinica P.O. Box 71010 Wuhan 430071 China

Let f(x, t): R2×R→ R be a C2-function with respect to t∈R, f(x,0) =0, f(x, t) ~ebt2 as t→+∞ for somc b>0. Under suitable conditions on f(x, t), author shows that for g∈L2 (R2), g(x)≥ 0, the following semilinear clliptic problem:has at least two distinct positive solutions for any λ∈(0, λ*), at least one positive solution for any λ∈ [λ*, λ*] and has no positive solntion for all λ>λ*. It is also proved that λ*≤λ*< +∞.

关键词： Positive solntion elliptic equations critical growth.

Molecule configurations modulate packing array and charge transfer in cocrystal engineering

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Science China Chemistry 2024年第2期67卷 512-516页

作者： Shenglong An Mengyuan Qiao Xin Jin Xuanying Chen Jianhua Su Lifang Guo Zhiyun Zhang Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CentreFrontiers Science Center for Materiobiology and Dynamic ChemistryEast China University of Science&TechnologyShanghai200237China

Organic cocrystal as an emerging assembly strategy has received increasing attention in constructing multiple functional materials,through continually screening suitable constituent monomers or changing their stoichiometry ratios.However,the role of molecule configuration in the cocrystal field is rarely explored despite the fascinating potential in regulating the packing mode.In this study,the N,N′-diphenyl-5,10-dihydrophenazine derivatives(DPPs) with the flexible scaffold and different methyl substitutions are selected as the donors bearing various molecular configurations.In a simple collaborative way,a series of cocrystals based on DPPs and OFN(octafluoronaphthalene) are fabricated,exhibiting two self-adaptive molecular stacking arrays.X-ray crystallographic analysis and theoretical calculation unveil their different π···π interactions and charge transfer characters,leading to the significant emission redshift up to 125 nm compared with individual DPPs.As a result,controllable molecule stacking structure,tunable emission,and charge transfer properties can be achieved.The study provides a new perspective to reveal the structure-property relationships at the molecular level by controlling the molecule configuration in cocrystal engineering,contributing to the development of cocrystal theoretical physics and organic functional materials.

关键词： cocrystals molecular configuration self-adaptive packing mode charge transfer