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Chinese Journal of Chemistry 2007年第6期25卷 869-871页

作者： OFORKA, n. C. MKPEnIE, V. n. Department of Pure and Industrial Chemistry University of Port Harcourt P. M. B. 5323 Port Harcourt Nigeria

A new method for the synthesis of azo Schiff an base ligand in which the azo and azomethine groups are coordination sites was developed through a Schiff base precursor. The precursor, n-4-methoxybenzylidene-3-hydroxyphenylamine （SB） derived from 3-aminophenol was regioselectively coupled with a diazonium ion para to the hydroxyl group of the amine component of the Schiff base. The para selectivity was controlled by the directing effect of the hydroxyl group. The ligand and its nickel（Ⅱ） complex were characterized by elemental analyses, IR and UV-Vis spectroscopy. The analytical and spectral data supported the mononuclear formulation of the complex with metal to ligand ratio （M ： L = 1 ： 2） and suggested a square planar geometry for the complex.

关键词： synthesis azo compound Schiff base ligand azo and azomethine donor

Ionic liquid-assisted hydrothermal synthesis of SnS nanoparticles:Electrode materials for lithium batteries,photoluminescence and photocatalytic activities

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Journal of Energy Chemistry 2018年第3期27卷 806-812页

作者： K.n.Manukumar G.nagaraju Brij Kishore C.Madhu n.Munichandraiah Department of Chemistry Siddaganga Institute of TechnologyTumkurKarnatakaIndia Department of Inorganic and Physical Chemistry Indian Institute of ScienceBangaloreKarnatakaIndiac Department of Physics.Siddaganga Institute of Technology.Tumkur KarnatakaIndia

Tin mono-sulphide（Sn S） nanoparticles（nps） have been successfully synthesised through ionic liquid assisted hydrothermal method using hydrated tin（ii） chloride as a precursor, thiourea as sulphur source precursors using 2-Methoxy ethyl methyl imidazolium methane sulfonate ionic liquid as co-solvent. The Reitveld refinement on powder X-ray diffraction（PXRD） confirmed the presence of orthorhombic Sn S structure as major phase along with traces amount of Sn S2 and Sn2 S3. Diffuse reflectance spectrum studies revealed the energy band gap around 1.38 e V. TEM images confirmed the Sn S nps with average particle size of 40 nm and HRTEM suggest good crystallinity. The electrochemical property for lithium storage behaviour shows an initial discharge capacity of 658 m Ah/g and it retains discharge capacity of 426 m Ah/g for 16 cycles, at current density 100 m A/g. The obtained results indicate that Sn S nps to be one of the possible promising anode materials for next generation Lithium batteries. Photoluminescence study of Sn S nps shows a strong green emission at 530 nm. Sn S nps were also tested for the photocatalytic adsorption of methylene blue and Rhodamine B.

关键词： nanoparticles Lithium-ion batteries Ionic liquids Ionothermal

The impact of age structure and vaccine prioritization on COVID-19 in West Africa

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Infectious Disease Modelling 2022年第4期7卷 709-727页

作者： Hemaho B.Taboe Michael Asare-Baah Afsana Yesmin Calistus n.ngonghala Department of Mathematics University of FloridaGainesvilleFL32611USA Laboratoire de Biomathematiques et d’Estimations Forestieres University of Abomey-CalaviCotonouBenin Department of Epidemiology University of Florida2004 Mowry RoadGainesvilleFL32610USA Emerging Pathogens Institute University of FloridaGainesvilleFL32610USA

The ongoing COVID-19 pandemic has been a major global health challenge since its emergence in *** to early predictions that sub-Saharan Africa(SSA)would bear a disproportionate share of the burden of COVID-19 due to the region's vulnerability to other infectious diseases,weak healthcare systems,and socioeconomic conditions,the pandemic's effects in SSA have been very mild in comparison to other ***,the number of cases,hospitalizations,and disease-induced deaths in SSA remain low,despite the loose implementation of non-pharmaceutical interventions(nPIs)and the low availability and administration of *** explanations for this low burden include epidemiological disparities,under-reporting(due to limited testing),climatic factors,population structure,and government policy *** this study,we formulate a model framework consisting of a basic model(in which only susceptible individuals are vaccinated),a vaccine-structured model,and a hybrid vaccine-age-structured model to assess the dynamics of COVID-19 in West Africa(WA).The framework is trained with a portion of the confirmed daily COVID-19 case data for 16 West African countries,validated with the remaining portion of the data,and used to(i)assess the effect of age structure on the incidence of COVID-19 in WA,(ii)evaluate the impact of vaccination and vaccine prioritization based on age brackets on the burden of COVID-19 in the sub-region,and(iii)explore plausible reasons for the low burden of COVID-19 in WA compared to other parts of the *** of the model parameters and global sensitivity analysis show that asymptomatic youths are the primary drivers of the pandemic in ***,the basic and control reproduction numbers of the hybrid vaccine-age-structured model are smaller than those of the other two models indicating that the disease burden is overestimated in the models which do not account for *** result is confirmed through the vaccine-d

关键词： Vaccine prioritization SARS-CoV-2 Omicron variant AVAT Reproduction number Herd immunity

A mixed problem of plate bending for doubly connected domains with partially unknown boundaries in the presence of cyclic symmetry

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Science China(Physics,Mechanics & Astronomy) 2010年第10期53卷 1884-1894页

作者： Odishelidze n Criado-Aldeanueva F Faculty of Exact and natural Sciences Tbilisi State University Department of Applied Physics ii University of Malaga

This paper addresses the problem of plate bending for a doubly connected body with outer and inner boundaries in the form of regular polygons with a common center and parallel *** neighborhoods of the vertices of the inner boundary are equal full-strength smooth arcs symmetric about the rays coming from the vertices to the center,but have unknown *** bars are attached to the linear parts of the *** plate bends by the moments applied to the middle point *** unknown arcs are free from external *** same problem of plate bending is considered for a regular hexagon weakened by a full-strength *** the methods of complex analysis,the analytical image of Kolosov-Muskhelishvili's complex potentials (characterizing an elastic equilibrium of the body),the plate deflection and unknown parts of its boundary are determined under the condition that the tangential normal moment on that plate takes a constant *** analyses are also performed and the corresponding graphs are constructed.

关键词： plate bending theory complex variable.

Interactive Effect of GA_3 ,n and P Ameliorate Growth, Seed and Fibre Yield by Enhancing Photosynthetic Capacity and Carbonic Anhydrase Activity of Linseed: A Dual Purpose Crop

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Journal of Integrative Agriculture 2013年第7期12卷 1183-1194页

作者： Mohammad n Khan Firoz Mohammad Department of Biology Faculty of Science University of Tabuk Plant Physiology Section Department of Botany Aligarh Muslim University

Linseed （Linum usitatissimum L.） is an important dual-purpose, industrial crop. Its seeds are used for the extraction of oil and stem for fibres. However, the production of linseed is not going parallel with the increasing demand of its products. The present work was carried out with an aim to find out whether exogenous application of gibberellic acid （GA3） with or without graded levels of nitrogen （n） and phosphorus （P） could improve the performance of three linseed genotypes Parvati, Shekhar and Shubhra together with minimizing the costly fertilizer input and losses. Four combinations of n and P, viz., 0 mg n＋0 mg P kg-1 soil （n0P0）, n13.4 P4.46 , n26.8P8.94 and n40.2P13.4 were constituted. Half dose of each combination was applied basally at the time of sowing and remaining half dose was given at 40 d after sowing （DAS） as foliar spray along with 10-6 mol L-1 GA3 . Prior to sowing, the seeds of each linseed genotype were grouped in to two, one group of seeds was soaked in 0 mol L-1 GA3 （control） and the other group was soaked in 10-6 M GA3 solution, each for 8 hours. Treatments were comprised of （i） 0 mol L-1 GA3＋n0P0 （T0 , control）, （ii） 10-6 mol L-1 GA3 ＋ n13.4P4.46 （T1）, （iii） 10-6 mol L-1 GA 3 ＋n 26.8 P 8.94 （T2） and （iv） 10-6 mol L-1 GA3＋n40.2P13.4 （T3）. The crop performance was assessed in terms of growth, physiological and biochemical parameters at 60 and 75 DAS and yield attributes at harvest （175 DAS）. The results showed a parallel increase in most of the parameters with increasing levels of n and P. However, application of 10-6 mol L-1 GA3 in association with n26.8P8.94 proved best, it enhanced seed yield, oil yield and fibre yield by 83.3, 97.3 and 78.7%, respectively accompanied with increase in net photosynthetic rate, carbonic anhydrase activity and dry matter accumulation. Among the genotypes tested, Shubhra performed best, while Parvati the least for most of the parameters studied. Thus, combined application of 10-6 mol L-1 GA3 plus n26.8P8.94 pro

关键词： gibberellin photosynthesis crbonic anhydrase linseed

Evaluation of groundwater quality using pollution index of groundwater(PIG) and non-carcinogenic health risk assessment in part of the Gangetic Basin

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Acta Geochimica 2021年第3期40卷 419-440页

作者： Apoorv Verma n.B.Singh Environmental Science and Engineering Civil Engineering DepartmentInstitute of Engineering and TechnologyDr.A.P.J.Abdul Kalam Technical UniversityLucknow 226021India Harcourt Butler Technical University Kanpur 208002India

The aim of this study was to evaluate groundwater fitness for domestic and irrigational use in Unnao district of Uttar Pradesh,*** this study,block wise(n=16)groundwater samples were collected,and measured parameters were analyzed using the pollution index of groundwater(PIG),various irrigational indices,and graphical *** results of this study suggested that most of the parameters were within the prescribed limits of WHO and BIS,excluding F-(0.4 to 2.6 mg L^(-1))and Fe^(2+)(0.1 to 1.7 mg L^(-1)).Concentrations of total dissolved solids(TDS)were exceeded the desirable limit(>500 mg L^(-1))in 43.75%of samples at some *** Gibbs plot revealed that groundwater chemistry was governed by rock-water interaction in the region,especially silicate *** Piper plot suggested that Ca^(2+)-HCO3-is dominant hydrochemical facies in the area followed by mixed Ca^(2+)-na^(+)-HCO_(3)^(-)type,na^(+)-Cl^(-)type,and na^(+)-HCO_(3)^(-)*** evaluation revealed that the contribution of F-and Fe2+in groundwater degradation is high in comparison to other elements in the region,about 18.75%samples showed low pollution,while about 6.25%samples shows moderate pollution,and 6.25%samples reflected high *** human health risk(HHR)assessment finding suggested that children(mean:1.36)are more vulnerable than adults(mean:1.01).Sodium absorption ration(SAR),Residual sodium carbonate(RSC),and Permeability index(PI)indicated that most of the groundwater was suitable for irrigation,whereas,Magnesium hazard ration(MHR)and Potential salinity(PS)indices suggested that only 37.5%and 56.25%of the samples were suitable for irrigational use,*** regional study would help in decision making for stakeholders and relevant authorities in the execution of groundwater management and remediation plans in the area.

关键词： Groundwater Pollution index of groundwater Irrigational indices Silicate weathering Human health risk

Localization on Certain Grothendieck Categories

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Acta Mathematica Sinica,English Series 2009年第3期25卷 379-392页

作者： F. CASTAn■O-IGLESIAS n.CHIFAn C.n■ST■SESCU Departamento de Estadística y Matemática Aplicada Universidad de Almería Department of Mathematics University of Galati Facultatea de Matematicǎ

Using categorical techniques we obtain some results on localization and colocalization theory in Grothendieck categories with a set of small projective generators. In particular, we give a sufficient condition for such category to be semiartinian. For semiartinian Grothendieck categories where every simple object has a projective cover, we obtain that every localizing subcategory is a TTF-class. In addition, some applications to semiperfect categories are obtained.

关键词： Grothendieck category localization colocalization semiartinian category semiperfect category

Scalable nanocomposite parylene-based memristors:Multifilamentary resistive switching and neuromorphic applications

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nano Research 2023年第2期16卷 3207-3214页

作者： Anna n.Matsukatova Artem Yu.Vdovichenko Timofey D.Patsaev Pavel A.Forsh Pavel K.Kashkarov Vyacheslav A.Demin Andrey V.Emelyanov national Research Centre“Kurchatov Institute” Moscow 123182Russia Physics Department Lomonosov Moscow State UniversityMoscow 119991Russia Moscow Institute of Physics and Technology DolgoprudnyjMoscow oblast 141701Russia Enikolopov Institute of Synthetic Polymeric Materials Russian Academy of SciencesMoscow 117993Russia Physics Department Saint Petersburg State UniversitySt.Petersburg 199034Russia

Memristors are promising candidates for synapse emulation in brain-inspired neuromorphic computing *** main obstacle to their usage in such systems is high variability of memristive characteristics and its severe negative effect on the neural network *** paper addresses the issue from two points of view on the example of the parylene-based memristors:(i)the methods of the memristor internal stochasticity decrease and(ii)the methods of the memristive neural network architecture *** introduction of an optimal Ag nanoparticle concentration(3 vol.%–6 vol.%)to the memristive structure leads to a statistically significant decrease in the switching voltage variation and endurance ***,it is shown that post-fabrication annealing improves memristive characteristics,e.g.,resistive switching window increases by an order of magnitude and exceeds 106,the switching voltage variation decreases by a factor of 2(down to 7%for the set and 17%for the reset voltage),and thermostability is *** transmission electron microscopy and impedance spectroscopy analysis allowed establishing a multifilamentary resistive switching mechanism for nanocomposite parylene-based *** simulation of the formal neural network based on these memristors demonstrates high classification accuracy with low variation for an important biomedical task,heart disease prediction,after careful feature selection and network architecture *** prospects of the controlled incorporation of the nanocomposite parylene-based memristors in neural networks are brightened by their scaling possibility in crossbar geometry.

关键词： memristor resistive switching neuromorphic computing parylene nanocomposite

Fractal interpolation:a sequential approach

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Applied Mathematics(A Journal of Chinese Universities) 2021年第3期36卷 330-341页

作者： n.Vijender M.A.navascus Department of Mathematics Visvesvaraya National Institute of Technology NagpurNagpur 440010India Departamento de Matem´atica Aplicada Escuela de Ingenier´ıa y ArquitecturaUniversidad de ZaragozaZaragoza 50018Spain

Fractal interpolation is a modern technique to fit and analyze scientific *** develop a new class of fractal interpolation functions which converge to a data generating(original)function for any choice of the scaling ***,our method offers an alternative to the existing fractal interpolation functions(FIFs).We construct a sequence of-FIFs using a suitable sequence of iterated function systems(IFSs).Without imposing any condition on the scaling vector,we establish constrained interpolation by using fractal *** particular,the constrained interpolation discussed herein includes a method to obtain fractal functions that preserve positivity inherent in the given *** existence of Cr--FIFs is *** identify suitable conditions on the associated scaling factors so that-FIFs preserve r-convexity in addition to the Cr-smoothness of original function.

关键词： fractal interpolation convergence sequence of operators constrained-FIFs fractal splines

Comparison between phylogeny of introns and exons in primates

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Chinese Science Bulletin 1999年第21期44卷 1940-1946页

作者： Wang, n Chen, RS Chinese Acad Sci Prot Engn Lab Inst Biophys Beijing 100101 Peoples R China

Introns and exons of 7 genes ( epsilon globin, gamma-1 globin, gamma-2 globin, delta globin, beta globin, Immunoglobulin and prepro-insulin) in primates have been separated out and used to infer phylogeny respectively. For each gene, results based on these two parts have been compared and showed that: ( i ) the topology of introns is almost

关键词： phylogeny inference intron substitution rate molecular evolution.