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Brightening room-temperature phosphorescence in solution

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Science China Chemistry 2023年第3期66卷 611-612页

作者： fei Nie Dongpeng yan Beijing Key Laboratory of Energy Conversion and Storage Materials Key Laboratory of RadiopharmaceuticalsMinistry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China

The strategies including noncovalent macrocycle-confined supramolecular assembly and construction of rigid hydrogen-bond network have been verified as effective routes to brighten aqueous-phase room temperature ***-based room-temperature phosphorescence(RTP)has attracted widespread attention in the fields of chemical sensors,optical anti-counterfeiting,information encoding and so on,due to unique characteristics of long excited-state lifetimes,large Stokes shifts and high signal-tonoise ratios[1,2].Currently,to obtain RTP with considerable efficiency and long lifetime,two brilliant strategies have been developed:one is the introduction of heavy atoms,which facilitates the spin-orbital coupling and intersystem crossing(ISC)from singlet to triplet states。

关键词： lifetime excited coupling

Comparative efficacy and safety of cognitive enhancers for treating vascular cognitive impairment: systematic review and Bayesian network meta-analysis

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Neural Regeneration Research 2019年第5期14卷 805-816页

作者： Bo-ru Jin Hua-yan Liu Department of Neurology First Affiliated Hospital China Medical University

Objective: To assess and compare the clinical efficacy and safety of cognitive enhancers(donepezil, galantamine, rivastigmine, and memantine) on cognition, behavior, function, and global status in patients with vascular cognitive *** sources: The initial literature search was performed with PubMed, EMBASE, the Cochrane Methodology Register, the Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing & Allied Health(CINAHL) from inception to January 2018 for studies regarding donepezil, galantamine, rivastigmine, and memantine for treatment of vascular cognitive *** selection: Randomized controlled trials on donepezil, galantamine, rivastigmine, and memantine as monotherapy in the treatment of vascular cognitive impairment were included. A Bayesian network meta-analysis was conducted. Outcome measures: Efficacy was assessed by changes in scores of the Alzheimer's Disease Assessment Scale, cognitive subscale, Mini-Mental State Examination, Neuropsychiatric Inventory scores and Clinician's Interview-Based Impression of Change Scale Plus Caregiver's Input, Activities of Daily Living, the Clinical Dementia Rating scale. Safety was evaluated by mortality, total adverse events(TAEs), serious adverse events(SAEs), nausea, vomiting. diarrhea, or cerebrovascular accidents(CVAs). Results: After screening 1717 citations, 12 randomized controlled trials were included. Donepezil and rivastigmine(mean difference(e) = –0.77, 95% confidence interval(CI): 0.25–1.32; MD = 1.05, 95% CI: 0.18–1.79) were significantly more effective than placebo in reducing Mini-Mental State Examination scores. Donepezil, galantamine, and memantine(MD = –1.30, 95% CI: –2.27 to –0.42; MD = –1.67, 95% CI: –3.36 to –0.06; MD = –2.27, 95% CI: –3.91 to –0.53) showed superior benefits on the Alzheimer's Disease Assessment Scale–cognitive scores compared with placebo. Memantine(MD = 2.71, 95% CI: 1.05–7.29) improved global status(Clinician's Interview-Based Impres

关键词： nerve regeneration vascular cognitive impairment vascular dementia pharmacotherapy cholinesterase inhibitors donepezil galantamine rivastigmine memantine systematic review Bayesian network meta-analysis neural regeneration

Microstructural evolution and mechanical properties of Ni-45Ti-5Al-2Nb-1Mo alloy subjected to different heat treatments

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Rare Metals 2023年第8期42卷 2774-2780页

作者： Xiao-Yun Song yan Li fei Zhang State Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co.LtdBeijing 101407China School of Materials Science and Engineering Beihang UniversityBeijing 100191China

The effects of solution and aging heat treatment on microstructural evolution and room temperature tensile properties for as-forged Ni-45Ti-5Al-2Nb-1Mo alloy were investigated through scanning electron microscopy(SEM),transmission electron microscopy(TEM)and tensile *** results show that the microstructure of solution-treated alloy comprises NiTi matrix,Ti_(2)Ni and(Nb,Ti)ss *** aging treatment at 700℃for 6 and100 h,the distribution of Ti_(2)Ni and(Nb,Ti)ss precipitates increases in *** new type of precipitate is observed in the specimen aged at 700℃.After aging at800℃for 100 h,numerous nanosized Ni_(2)TiAl phases are precipitated within the *** and aging treatments improve the tensile properties at room *** strength and ductility are improved after solution treatment at 1100℃plus aging treatment at 800℃for 6 h or 700℃for 100 *** aging time prolonging to 100 h at 800℃,the precipitation of fine Ni2TiAl particles leads to the improvement in tensile strength and deterioration of elongation.

关键词： NiTi-Al-based alloy Intermetallics Microstructure Mechanical properties Heat treatment

Nevanlinna theory through the Brownian motion

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Science China Mathematics 2019年第11期62卷 2131-2154页

作者： Xianjing Dong yan He Min ru Department of Mathematics Nanjing UniversityNanjing 210093China Department of Mathematics University of HoustonHoustonTX 77004USA

In this paper, we introduce the Nevanlinna theory using stochastic calculus, following the works of Davis(1975), Carne(1986) and Atsuji(1995, 2005, 2008 and 2017), etc. In particular, we give(another) proofs of the classical result of Nevanlinna for meromorphic functions and the result of Cartan-Ahlfors for holomorphic curves by using the probabilistic method.

关键词： Nevanlinna theory holomorphic curves second main theorem Brownian motion

Inhibitory Effects of Natural Compound Alantolactone on Human Non-small Cell Lung Cancer A549 Cells

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Chemical Research in Chinese Universities 2011年第2期27卷 241-244页

作者： ZONG Min-ru ZHAO Ying-hao ZHANG Kun yanG Long-fei ZHENG Yong-chen HE Cheng-yan China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China The Second Hospital of Jilin University Changchun 130041 P. R. China

Alantolactone is a natural compound identified from the roots of Inula helenium L. that has multiple bio-activities. We examined its inhibitory effects on human non-small cell lung cancer（NSCLC） A549 cells. The an-tiproliferative effect of alantolactone on A549 cells was investigated via MTT[3′-（4,5dimethylthiazol-2-yl）-2,5- diphenyl tetrazolium bromide] assay and its apoptosis-inducing effect was determined by Hoechst staining and flow cytometry. We found that alantolactone significantly inhibited the proliferation of A549 cells and induced morphological changes typical for apoptosis. Flow cytometry analysis indicates dose-dependent cell cycle retardation at G0/G1 and S stages. The results indicate that alantolactone could be an attractive small-molecular natural compound for further development as a therapeutic drug against NSCLC.

关键词： Alantolactone Non-small cell lung cancer(NSCLC) A549 Proliferation Apoptosis

Existence and Stability of Solutions to Highly Nonlinear Stochastic Differential Delay Equations Driven by G-Brownian Motion

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Applied Mathematics(A Journal of Chinese Universities) 2019年第2期34卷 184-204页

作者： fei Chen fei Wei-yin yan Li-tan Glorious Sun School of Business and Management Donghua UniversityShanghai200051China School of Mathematics and Physics Anhui Polytechnic UniversityWuhuAnhui 241000China

Under linear expectation (or classical probability), the stability for stochastic differential delay equations (SDDEs), where their coefficients are either linear or nonlinear but bounded by linear functions, has been investigated intensively. Recently, the stability of highly nonlinear hybrid stochastic differential equations is studied by some researchers. In this paper, by using Peng’s G-expectation theory, we first prove the existence and uniqueness of solutions to SDDEs driven by G-Brownian motion (G-SDDEs) under local Lipschitz and linear growth conditions. Then the second kind of stability and the dependence of the solutions to G-SDDEs are studied. Finally, we explore the stability and boundedness of highly nonlinear G-SDDEs.

关键词： stochastic differential delay equation (SDDE) sublinear expectation existence and uniqueness G-Brownian motion stability and boundedness

Prediction of mechanical properties of cold rolled strip based on improved extreme random tree

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Journal of Iron and Steel Research International 2023年第2期30卷 293-304页

作者： Yun-bao Zhao Yong Song fei-fei Li Xian-le yan Institute of Engineering Technology University of Science and Technology BeijingBeijing100083China

Taking the 2130 cold rolling production line of a steel mill as the research object,feature dimensionality reduction and decoupling processing were realized by fusing random forest and factor analysis,which reduced the generation of weak decision trees while ensured its *** base learner used a weighted voting mechanism to replace the traditional average method,which improved the prediction ***,the analysis method of the correlation between steel grades was proposed to solve the problem of unstable prediction accuracy of multiple steel *** experimental results show that the improved prediction model of mechanical properties has high accuracy:the prediction accuracy of yield strength and tensile strength within the error of±20 MPa reaches 93.20%and 97.62%,respectively,and that of the elongation rate under the error of±5%has reached 96.60%.

关键词： Cold strip rolling Mechanical property prediction Extreme random tree Factor analysis Random forest Correlation analysis Steel grade

Enhancing coercivity and thermal stability of(Nd,Y)-Fe-B sintered magnets through lamellar structure design

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Rare Metals 2024年第12期43卷 6571-6582页

作者： Xiao-Dong Fan Yu-Hao Li Shuai Cao Guang-fei Ding Shuai Guo Bo Zheng Ren-Jie Chen A.ru yan CISRI & NIMTE Joint Innovation Center for Rare Earth Permanent Magnets Ningbo Institute of Materials Technology and EngineeringChinese Academy of Sciences School of Materials Science and Chemical Engineering Ningbo University University of Chinese Academy of Sciences

The incorporation of the high-abundance rareearth element Y in(Nd,Y)-Fe-B sintered magnets offers an opportunity to reduce the cost of permanent magnetic materials,while promoting the balanced usage of rare-earth ***,the performance of(Nd,Y)-Fe-B magnets prepared using the conventional dual-main-phase(DMP) method undergoes significant degradation due to the strong diffusion ability of *** suppress the excessive diffusion of Y,this study presents a macroscopic lamellar magnet preparation ***,the micromagnetic simulations revealed that the multilayer magnets exhibited superior intrinsic performance compared to DMP ***,the multilayer magnets were prepared by alternately stacking the 0% Y(0Y) and 30% Y(30Y) magnetic *** observed magnetic properties demonstrated that the coerc)vity of the three-layer magnet was～0.23 T higher than that of the DMP magnet,leading to improved coercivity stability at high ***,the microstructural observations and elemental analyses indicated the presence of a～200-μm-thick interface layer at the contact site between the 0Y and 30Y magnetic ***,the proposed approach effectively suppressed the excessive diffusion of Y in(Nd,Y)-Fe-B magnets,thereby enhancing the magnetic performance of the sintered magnets.

关键词： Coercivity Lamellar structure design Nd–Y–Fe–B magnets Thermal stability

DUAL RECIPROCITY HYBRID BOUNDARY NODE METHOD FOR THREE-DIMENSIONAL ELASTICITY WITH BODY FORCE

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Acta Mechanica Solida Sinica 2008年第3期21卷 267-277页

作者： fei yan Yuanhan Wang Yu Miao fei Tan School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China

Combining Dual Reciprocity Method （DRM） with Hybrid Boundary Node Method （HBNM）, the Dual Reciprocity Hybrid Boundary Node Method （DRHBNM） is developed for three-dimensional linear elasticity problems with body force. This method can be used to solve the elasticity problems with body force without domain integral, which is inevitable by HBNM. To demonstrate the versatility and the fast convergence of this method, some numerical examples of 3-D elasticity problems with body forces are examined. The computational results show that the present method is effective and can be widely applied in solving practical engineering problems.

关键词： hybrid boundary node method dual reciprocity method body force radial basis function