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Chinese Journal of Chemistry 1996年第4期14卷 315-320页

作者： Zang, l Shen, t CHINESE ACAD SCI INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

the optical effects of the adsorption of eosin on the colloidal sliver particle have been investigated in aqueous solutions. It was found that upon adsorption the fluorescence of eosin was effectively quenched. this was explained as the photoinduced interfacial electron transfer from the excited singlet state of eosin to the silver particle. Decreasing pH of the solution favors the adsorption of eosin and so enhances the fluorescence quenching. For comparison, the fluorescence quenching in reverse micelles was also investigated. the quenching behavior was much different from that mediated in aqueous solution. this was attributed to the unique microenvironment of reverse micelles.

关键词： photoinduced electron transfer eosin reverse micelle

Genes associated with Alzheimer's disease affecting ischemic neurodegeneration of the hippocampal CA3 region

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Neural Regeneration Research 2021年第7期16卷 1392-1393页

作者： Ryszard Pluta Marzena ułamek-Kozioł laboratory of Ischemic and Neurodegenerative Brain Research Mossakowski Medical Research CentrePolish Academy of SciencesWarsawPoland

Neurodegeneration in the brain after ischemia with reperfusion mimicking the neuropathology of Alzheimer's disease:Brain ischemia with reperfusion,which is one of the main causes of morbidity and mortality in the world,triggers various neuropathological changes characteristic for Alzheimer's disease(AD)such as increased blood-brain barrier permeability,excitotoxicity,necrosis,autophagy,mitophagy,apoptosis,neuroinflammation,amyloid plaques,neurofibrillary tangles,cerebral vessel pathology,and brain atrophy that lead to the death of neurons,deteriorating motor,sensory and cognitive functions(Figure 1)(Kato et al.,1988;Wisniewski et al.,1995;Van Groen et al.,2005;Kocki et al.,2015;ułamek-Koziołet al.,2016,2017,2019).Brain ischemia is recognized as a major contributor to the dysfunction of an aging brain and the development of neurodegenerative diseases,including AD(Pluta,2019).

关键词： Alzheimer ischemia cerebral

Rare-earth elements as source indicators of Pan-African granites from Obudu Plateau,Southeastern Nigeria

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Chinese Journal Of Geochemistry 2008年第2期27卷 130-134页

作者： ukaegbu V.u. Beka F.t. Department of Geology University of Port HarcourtPort HarcourtNigeria

the rare-earth element (REE) concentrations of representative granite samples from the southeast of the Obudu Plateau, Nigeria, were analyzed with an attempt to determine the signatures of their source, evolutionary history and tectonic setting. Results indicated that the granites have high absolute REE concentrations (190×10-6-1191×10-6; av.=549×10-6) with the chondrite-normalized REE patterns characterized by steep negative slopes and prominent to slight or no negative Eu anomalies. All the samples are also characterized by high and variable concentrations of the lREE (151×10-6-1169×10-6; av.= 466×10-6), while the HREE show low abundance (4×10-6-107×10-6; av.=28×10-6). these are consistent with the variable levels of REE fractionation, and differentiation of the granites. this is further supported by the range of REE contents, the chondrite-normalized patterns and the ratios of laN/YbN (2.30-343.37), CeN/YbN (5.94-716.87), laN/SmN (3.14-11.68) and tbN/YbN (0.58-1.65). the general parallelism of the REE patterns, suggest that all the granites were comagmatic in origin, while the high Eu/Eu* ratios (0.085-2.807; av.=0.9398) indicate high fO2 at the source. Similarly, irregular variations in laN/YbN, CeN/YbN and Eu/Eu* ratios and REE abundances among the samples suggest behaviors that are related to mantle and crustal sources.

关键词：指示剂稀土元素非洲花岗岩

Influence of ageing on oil degradation and gassing tendency under high-energy electrical discharge faults for mineral oil and synthetic ester

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High Voltage 2020年第6期5卷 731-738页

作者： l.loiselle u.Mohan Rao I.Fofana Research Chair on the Aging of Power Network Infrastructure(ViAHt) Universitédu QuébecàChicoutimiChicoutimiQCG7H 2B1Canada

In this work, mineral oil and synthetic esters were selected at different ageing factors (based on acidity values). Fresh and aged oils have been subjected to high-energy discharges (repeated 100 breakdowns) to simulate electric faults of highly vulnerable intensity. the intent of this work is to understand the influence of high-energy electric faults on oil degradation and gassing tendency at different ageing conditions. In this study, the influence of the high-energy discharges on degradation and gassing tendency at different ageing factors is reported for mineral oil and synthetic esters. Oil degradation is reported by adopting ultraviolet spectroscopy, turbidity and particle counter as per american society for testing and materials (AStM) standard test methods. Gassing tendencies and fault gas analysis are understood by dissolved the gas analysis using Duval's triangle and Duval's pentagon methods for mineral and non-mineral oils. It is found that the influence of high-energy discharges on oil degradation is higher in mineral oils to that of the synthetic esters. the intensity of the gassing tendency is higher for ester fluids;however, as per the Duval methods, the faulty conditions are at lower levels as compared to mineral oils.

关键词： synthetic energy high

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cellular & Molecular Immunology 2024年第2期21卷 103-118页

作者： S.Cankat M.u.Demael l.Swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

Members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent *** this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus *** will detail the unmet clinical need associated with the continued transmission of SARS-CoV-2,MERS-CoV and the four seasonal coronaviruses(HCoV-OC43,Nl63,HKu1 and 229E)in humans and the potential for future zoonotic *** will highlight how first-generation SARS-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer ***,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection universal

FuRtHER INVEStIGAtION INtO APPROXIMAtION OF A COMMON SOlutION OF FIXED POINt PROBlEMS AND SPlIt FEASIBIlItY PROBlEMS

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Acta Mathematica Scientia 2016年第3期36卷 913-930页

作者： Y.SHEHu O.t.MEWOMO F.u.OGBuISI Department of Mathematics University of Nigeria School of Mathematics Statistics and Computer ScienceUniversity of Kwazulu-Natal

the purpose of this paper is to study and analyze an iterative method for finding a common element of the solution set ~ of the split feasibility problem and the set F（t） of fixed points of a right Bregman strongly nonexpansive mapping t in the setting of p- uniformly convex Banach spaces which are also uniformly smooth. By combining Mann＇s iterative method and the Halpern＇s approximation method, we propose an iterative algorithm for finding an element of the set F（t）∩Ω moreover, we derive the strong convergence of the proposed algorithm under appropriate conditions and give numerical results to verify the efficiency and implementation of our method. Our results extend and complement many known related results in the literature.

关键词： strong convergence split feasibility problem uniformly convex uniformly smooth fixed point problem right Bregman strongly nonexpansive mappings

Dynamics of the phase-change material Gete across the structural phase transition

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Frontiers of physics 2019年第2期14卷 65-71页

作者： t. Chatterji S. Rols u. D. Wdowik Institut.l.ue-langevin 71 avenue des Martyres38000 GrenobleFrance Institut of technology Pedagogical UniversityPodchorazych 2PL-30-084 KrakowPoland

Results of inelastic neutron scattering experinients and ab initio molecular dynamics simulations for Gete 一 the parent compound of phase-change materials are reported. the inelastic neutron spectra of Gete powder samples have been determined in the temperature range extending from 300 to 700 K. the phonon peaks undergo thermal shifts resulting from anharmonic effects being weaker for acoustic than optic modes. A small concentration of free charge carries arising from the presence of Ge-vacancies was found not to affect significantly the neutron weighted phonon densities of states of Gete. the spectral pattern changes qualitatively across the structural phase transition, but the local structure of Gete remains hardly affected, as confirmed by the analysis of temperature dependence of the pairdistribution function obtained from ab initio molecular dynamics investigations. the present theoretical studies support in a wide extent our experimental observations and also those provided by local probe methods.

关键词： phase-change mat erials inelastic neutron scattering ab initio molecular dynamics

Improved prediction of clay soil expansion using machine learning algorithms and meta-heuristic dichotomous ensemble classifiers

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Geoscience Frontiers 2022年第1期13卷 268-284页

作者： E.u.Eyo S.J.Abbey t.t.lawrence F.K.tetteh Department of Geography and Environmental Management University of the West of EnglandBristolUnited Kingdom Research Centre for Fluid and Complex Systems Coventry UniversityCoventryUnited Kingdom Department of Civil Engineering University of BirminghamBirminghamUnited Kingdom

Soil swelling-related disaster is considered as one of the most devastating geo-hazards in modern ***,proper determination of a soil’s ability to expand is very vital for achieving a secure and safe ground for ***,this study has provided a novel and intelligent approach that enables an improved estimation of swelling by using kernelised machines(Bayesian linear regression(BlR)&bayes point machine(BPM)support vector machine(SVM)and deep-support vector machine(D-SVM));(multiple linear regressor(REG),logistic regressor(lR)and artificial neural network(ANN)),tree-based algorithms such as decision forest(RDF)&boosted trees(BDt).Also,and for the first time,meta-heuristic classifiers incorporating the techniques of voting(VE)and stacking(SE)were *** independent scenarios of explanatory features’combination that influence soil behaviour in swelling were *** results indicated BlR as possessing the highest amount of deviation from the predictor variable(the actual swell-strain).REG and BlR performed slightly better than ANN while the meta-heuristic learners(VE and SE)produced the best overall performance(greatest R2 value of 0.94 and RMSE of 0.06%exhibited by VE).CEC,plasticity index and moisture content were the features considered to have the highest level of *** binary classifiers(SVM,D-SVM and BPM)gave better accuracy(average accuracy and recall rate of 0.93 and 0.60)compared to ANN,lR and ***-driven diagnostic test indicated that the meta-heuristic models’best performance occurred when Ml training was conducted using k-fold validation ***,it is recommended that the concepts developed herein be deployed during the preliminary phases of a geotechnical or geological site characterisation by using the best performing meta-heuristic models via their background coding resource.

关键词： Artificial neural networks Machine learning Clays Algorithm Soil swelling Soil plasticity

the Isentropic Exponent of Single-Ionized Mono-Atomic Plasmas

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Plasma Science and technology 2012年第8期14卷 699-701页

作者： K.t.A.l.BuRM PlasmAIX for Plasma Research Heimerik 472440 GeelBelgium

the isentropic exponent of single-ionized mono-atomic plasmas in thermal equilib- rium is studied. Its behavior as a function of the ionization degree and temperature is examined for argon and zinc plasmas at two pressures （1 bar and 1 mbar, 1 mPa and 1 Pa）, respectively. the results show that for the two sorts of plasma the isentropic exponent equals typically about 1.1-1.2 within a considerably wide range of the ionization degree （5%-80%）.

关键词： plasma modelling isentropic exponent

Brownian motion and thermophoresis effects on unsteady stagnation point flow of Eyring-Powell nanofluid: a Galerkin approach

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Communications in theoretical Physics 2020年第12期72卷 71-82页

作者： Z H Khan M usman t Zubair M Hamid R u Haq State Key laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China BIC-ESAt College of EngineeringPeking UniversityBeijing 100871China State Key laboratory for turbulence and Complex Systems Department of Mechanics and Engineering SciencePeking UniversityBeijing 100871China Institute of Ocean Research Peking UniversityBeijing 100871China School of Mathematical Sciences Peking UniversityBeijing 100871China Department of Mechanics and Engineering Science Fudan UniversityShanghai 200433China Department of Electrical Engineering Bahria UniversityIslamabad CampusIslamabad 44000Pakistan

this article concerns the analysis of an unsteady stagnation point flow of Eyring–Powell nanofluid over a stretching *** influence of thermophoresis and Brownian motion is also considered in transport *** nonlinear ODE set is obtained from the governing nonlinear equations via suitable *** numerical experiments are performed using the Galerkin scheme.A tabular form comparison analysis of outcomes attained via the Galerkin approach and numerical scheme(RK-4)is available to show the credibility of the Galerkin *** numerical exploration is carried out for various governing parameters,namely,Brownian motion,steadiness,thermophoresis,stretching ratio,velocity slip,concentration slip,thermal slip,and fluid parameters,and Hartmann,Prandtl and Schmidt *** velocity of fluid enhances with an increase in fluid and magnetic parameters for the case of opposing,but the behavior is reversed for assisting *** Brownian motion and thermophoresis parameters cause an increase in temperature for both cases(assisting and opposing).the Brownian motion parameter provides a drop-in concentration while an increase is noticed for the thermophoresis *** the outcomes and the behavior of emerging parameters are illustrated *** comparison analysis and graphical plots endorse the appropriateness of the Galerkin *** is concluded that said method could be extended to other problems of a complex nature.

关键词： Eyring-Powell fluid stagnation point flow Brownian motion and thermophoresis Galerkin method