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Progress in Natural Science:Materials International 2013年第3期23卷 222-234页

作者： John Meurig Thomas paul a.midgley Caterina Ducati Rowan K.Leary Department of Materials Science and Metallurgy University of CambridgePembroke StreetCambridgeCB2 3QZUK

The outstanding merits of scanning transmission electron tomography as a technique for the investigation of the internal structure and morphology of nanoparticle and nanocluster materials are summarized with the aid of numerous typical *** is made also to the significant advances that have arisen in probing ultrastructural characteristics of nanoscale solids using aberrationcorrected(AC) electron microscopy(EM).Information of a unique kind may be retrieved by combining the imaging and analytical power of ACEM.

关键词： Nanoclusters Nanoparticles Atomic structure Electron tomography Aberration-corrected electron microscopy

3-D Characterization of CdSe Nanoparticles Attached to Carbon Nanotubes

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Nano Research 2008年第1期1卷 89-97页

作者： Ana B.Hungría Beatriz H.Juárez Christian Klinke Horst Weller paul a.midgley Department of Materials Science and Metallurgy University of CambridgePembroke StreetCambridgeCB23QZUK 2 Institute of Physical ChemistryUniversity of Hamburg20146 HamburgGermany

The crystallographic structure of CdSe nanoparticles attached to carbon nanotubes has been elucidated by means of high resolution transmission electron microscopy and high angle annular dark field scanning transmission electron microscopy *** rod-like nanoparticles,grown in solution together with carbon nanotubes,undergo a morphological transformation and become attached to the carbon *** tomography reveals that the nanoparticles are hexagonal-based with the(001)planes epitaxially matched to the outer graphene layer.

关键词： Electron tomography CdSe nanoparticles STEM HRTEM carbon nanotubes

Single-atom heterogeneous catalysts based on distinct carbon nitride scaffolds

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National Science Review 2018年第5期5卷 642-652页

作者： Zupeng Chen Evgeniya Vorobyeva Sharon Mitchell Edvin Fako Nuúria López Sean M.Collins Rowan K.Leary paul a.midgley RolAND Hauert Javier Pérez-Ramírez Institute for Chemical and Bioengineering Department of Chemistry and Applied BiosciencesETHZurich Institute of Chemical Research of Catalonia (ICIQ) The Barcelona Institute of Science and Technology 3. Department of Materials Science and MetallurgyUniversity of Cambridge 4. EmpaSwiss Federal Laboratories for Materials Science and Technology

Carbon nitrides integrating macroheterocycles offer unique potential as hosts for stabilizing metal atoms due to their rich electronic structure. To date, only graphitic heptazine-based polymers have been ***, we demonstrate that palladium atoms can be effectively isolated on other carbon nitride scaffolds including linear melem oligomers and poly(triazine/heptazine imides). Increased metal uptake was linked to the larger cavity size and the presence of chloride ions in the polyimide structures. Changing the host structure leads to significant variation in the average oxidation state of the metal, which can be tuned by exchange of the ionic species as evidenced by X-ray photoelectron spectroscopy and supported by density functional theory. Evaluation in the semi-hydrogenation of 2-methyl-3-butyn-2-ol reveals an inverse correlation between the activity and the degree of oxidation of palladium, with oligomers exhibiting the highest activity. These findings provide new mechanistic insights into the influence of the carbon nitride structure on metal stabilization.

关键词： single-atom heterogeneous catalysts carbon nitride scaffolds alkyne semi-hydrogenation density functional theory metal–host interaction

Towards a sustainable geoliner construction in landflls by potential blending of fly ash with kaolin clay alternative:a review with an insight to Indian scenario

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Waste Disposal and Sustainable Energy 2024年第2期6卷 243-258页

作者： Kshitij Kumar Biswajit paul Department of Environmental Science and Engineering Indian Institute of Technology(Indian School of Mines)Dhanbad 826004JharkhandIndia

Electricity generated through coal-based Thermal Power Plants(TPPs)has played a pivotal role in shaping modern civiliza-tion,revolutionizing industries,and improving the quality of life for billions of people *** TPPs contribute to about 37%-40%of the global energy *** production,in turn,has a direct impact on the economy of any *** from this boon to humankind,these TPPs combusting coal as their primary fuel also have specific environmen-tal impacts,the major ones being water,air,and soil pollution due to unscientific disposal of high-quantity fly ash produced *** we can put this ash to good use,it may assist us in mitigating the pollution caused by *** there are many conventional uses of fly ash,such as a pozzolanic material in the cement industry,more pathways need to be discovered to balance the high generation quantities with ***,a detailed description of its use in potential geoliner applications is presented in this article.A geoliner or a landfill liner acts as a virtually impenetrable layer to mitigate the leachate penetration into the underneath subsoil and groundwater,thus preventing *** are presently some studies that support the use of only fly ash in such ***,the properties of the geoliners using it are not so good to significantly mitigate environmental degradation owing to its high permeability and low densification *** bentonite conventionally used has limited deposits and is mined intensively for its use as a natural *** depos-its must also be conserved,and an alternative material that may serve similar application benefits,like bentonite,must be *** desired aim can be fulfilled if we blend this combustion residue with other suitable materials(such as kaolinite clay)with low ***,the article focuses on the possibilities of blending fly ash with different clays for geoliner construction to improve the in

关键词： Fly ash-Geoliner Environmental management Composite liner systems Bentonite Kaolin clay

Strain-dependent alpha-synuclein spreading in Parkinson's disease and multiple system atrophy

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Neural Regeneration Research 2024年第12期19卷 2581-2582页

作者： Shuyu Zhang paul Lingor Department of Neurology School of MedicineUniversity Hospital rechts der IsarTechnical University of MunichMunichGermany Department of Neurology University Medical Center GöttingenGöttingenGermany Center for Biostructural Imaging of Neurodegeneration University Medical Center GöttingenGöttingenGermany

Parkinson's disease(PD) and atypical Parkinsonian syndromes,such as multiple system atrophy(MSA) and Dementia with Lewy bodies,are neurodegenerative movement disorders characterized by the accumulation of alphasynuclein(a-syn) *** a-syn aggregates propagate throughout the brain in a prion-like manner,where pathological a-syn recruits endogenous a-syn to form insoluble *** forms representing intermediates on the way to insoluble aggregates result in the most pronounced neurotoxic effects.

关键词： atrophy endogenous atypical

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Tensor perturbations from bounce inflation scenario in f(Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun Hu Tanmoy paul Taotao Qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor power spectrum is obtained both for large as well as small scale *** a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation ***,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

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Smoking of Carica papaya in Nigeria:The rationale,the public health effects and policies for intervention

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Asian Pacific Journal of Tropical Medicine 2024年第3期17卷 95-96页

作者： Abolaji paul Adekeye Mental Health Department Federal Teaching HospitalIdo-EkitiEkiti StateNigeria Mental Health Department Afe Babalola UniversityAdo-EkitiEkiti StateNigeria

Psychoactive substance use is characterized by the habitual use of substances that have significant effects in altering the activities of neurotransmitters in certain regions of the ***,these alterations manifest as c... 详细信息

关键词： rational behaviour emotional

Surface engineering with ionic polymers on membranes for boron removal

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： Xiting Zhang Chenyi Fang J paul Chen Sui Zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering

The great catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul B.Wignall David P.G.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the Permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Prediction of Bandwidth of Metamaterial Antenna Using Pearson Kernel-Based Techniques

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Computers, Materials & Continua 2024年第3期78卷 3449-3467页

作者： Sherly Alphonse S.Abinaya Sourabh paul School of Computer Science and Engineering Vellore Institute of TechnologyChennai600127India School of Electronics Engineering Vellore Institute of TechnologyChennai600127India

The use of metamaterial enhances the performance of a specific class of antennas known as metamaterial *** radiation cost and quality factor of the antenna are influenced by the size of the *** antennas allow for the circumvention of the bandwidth restriction for small *** parameters have recently been predicted using machine learning algorithms in existing *** learning can take the place of the manual process of experimenting to find the ideal simulated antenna *** accuracy of the prediction will be primarily dependent on the model that is *** this paper,a novel method for forecasting the bandwidth of the metamaterial antenna is proposed,based on using the Pearson Kernel as a standard *** with these new approaches,this paper suggests a unique hypersphere-based normalization to normalize the values of the dataset attributes and a dimensionality reduction method based on the Pearson kernel to reduce the dimension.A novel algorithm for optimizing the parameters of Convolutional Neural Network(CNN)based on improved Bat Algorithm-based Optimization with Pearson Mutation(BAO-PM)is also presented in this *** prediction results of the proposed work are better when compared to the existing models in the literature.

关键词： Antenna pearson optimization bandwidth metamaterial