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71.
Andrés Guerrero‐Martínez Jorge Pérez‐Juste Luis M. Liz‐Marzán 《Advanced materials (Deerfield Beach, Fla.)》2010,22(11):1182-1195
In recent years, new strategies for silica coating of inorganic nanoparticles and organic nanomaterials, which differ from the classical methodologies, have emerged at the forefront of materials science. Silica as a coating material promises an unparalleled opportunity for enhancement of colloidal properties and functions by using core–shell rational designs and profiting from its synthetic versatility. This contribution provides a brief overview of recent progress in the synthesis of silica‐coated nanomaterials and their significant impact in different areas such as spectroscopy, magnetism, catalysis, and biology. 相似文献
72.
73.
Barkham Michael; Margison Frank; Leach Chris; Lucock Mike; Mellor-Clark John; Evans Chris; Benson Liz; Connell Janice; Audin Kerry; McGrath Graeme 《Canadian Metallurgical Quarterly》2001,69(2):184
To complement the evidence-based practice paradigm, the authors argued for a core outcome measure to provide practice-based evidence for the psychological therapies. Utility requires instruments that are acceptable scientifically, as well as to service users, and a coordinated implementation of the measure at a national level. The development of the Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) is summarized. Data are presented across 39 secondary-care services (n?=?2,710) and within an intensively evaluated single service (n?=?1,455). Results suggest that the CORE-OM is a valid and reliable measure for multiple settings and is acceptable to users and clinicians as well as policy makers. Baseline data levels of patient presenting problem severity, including risk, are reported in addition to outcome benchmarks that use the concept of reliable and clinically significant change. Basic quality improvement in outcomes for a single service is considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
This article presents the formulation of an enriched macro finite element based on the trigonometric shear deformation theory for the static analysis of symmetrically laminated composite plates. Shear correction factor is not required because this theory accounts for tangential stress-free boundary conditions on the plate boundary surfaces. The macro element is obtained using the principle of virtual work and Gram-Schmidt orthogonal polynomials as enrichment functions. The implementation of the obtained algorithm is simple and efficient, and allows studying general quadrilateral plates with a single macro element. Several examples are presented to show the capability and applicability of the developed formulation. 相似文献
75.
Encapsulation of Single Plasmonic Nanoparticles within ZIF‐8 and SERS Analysis of the MOF Flexibility 下载免费PDF全文
Guangchao Zheng Sarah de Marchi Vanesa López‐Puente Kadir Sentosun Lakshminarayana Polavarapu Ignacio Pérez‐Juste Eric H. Hill Sara Bals Luis M. Liz‐Marzán Isabel Pastoriza‐Santos Jorge Pérez‐Juste 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(29):3935-3943
Hybrid nanostructures composed of metal nanoparticles and metal‐organic frameworks (MOFs) have recently received increasing attention toward various applications due to the combination of optical and catalytic properties of nanometals with the large internal surface area, tunable crystal porosity and unique chemical properties of MOFs. Encapsulation of metal nanoparticles of well‐defined shapes into porous MOFs in a core–shell type configuration can thus lead to enhanced stability and selectivity in applications such as sensing or catalysis. In this study, the encapsulation of single noble metal nanoparticles with arbitrary shapes within zeolitic imidazolate‐based metal organic frameworks (ZIF‐8) is demonstrated. The synthetic strategy is based on the enhanced interaction between ZIF‐8 nanocrystals and metal nanoparticle surfaces covered by quaternary ammonium surfactants. High resolution electron microscopy and tomography confirm a complete core–shell morphology. Such a well‐defined morphology allowed us to study the transport of guest molecules through the ZIF‐8 porous shell by means of surface‐enhanced Raman scattering by the metal cores. The results demonstrate that even molecules larger than the ZIF‐8 aperture and pore size may be able to diffuse through the framework and reach the metal core. 相似文献
76.
Mingsong Wang Zilong Wu Alex Krasnok Tianyi Zhang Mingzu Liu He Liu Leonardo Scarabelli Jie Fang Luis M. Liz‐Marzn Mauricio Terrones Andrea Al Yuebing Zheng 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(31)
Strong spatial confinement and highly reduced dielectric screening provide monolayer transition metal dichalcogenides with strong many‐body effects, thereby possessing optically forbidden excitonic states (i.e., dark excitons) at room temperature. Herein, the interaction of surface plasmons with dark excitons in hybrid systems consisting of stacked gold nanotriangles and monolayer WS2 is explored. A narrow Fano resonance is observed when the hybrid system is surrounded by water, and the narrowing of the spectral Fano linewidth is attributed to the plasmon‐enhanced decay of dark K‐K excitons. These results reveal that dark excitons in monolayer WS2 can strongly modify Fano resonances in hybrid plasmon–exciton systems and can be harnessed for novel optical sensors and active nanophotonic devices. 相似文献
77.
Budhitama Subagdja Liz Sonenberg Iyad Rahwan 《Autonomous Agents and Multi-Agent Systems》2009,18(3):417-470
Dealing with changing situations is a major issue in building agent systems. When the time is limited, knowledge is unreliable,
and resources are scarce, the issue becomes more challenging. The BDI (Belief-Desire-Intention) agent architecture provides
a model for building agents that addresses that issue. The model can be used to build intentional agents that are able to
reason based on explicit mental attitudes, while behaving reactively in changing circumstances. However, despite the reactive
and deliberative features, a classical BDI agent is not capable of learning. Plans as recipes that guide the activities of the agent are assumed to be static. In this paper, an architecture for an intentional learning
agent is presented. The architecture is an extension of the BDI architecture in which the learning process is explicitly described
as plans. Learning plans are meta-level plans which allow the agent to introspectively monitor its mental states and update
other plans at run time. In order to acquire the intricate structure of a plan, a process pattern called manipulative abduction
is encoded as a learning plan. This work advances the state of the art by combining the strengths of learning and BDI agent
frameworks in a rich language for describing deliberation processes and reactive execution. It enables domain experts to specify
learning processes and strategies explicitly, while allowing the agent to benefit from procedural domain knowledge expressed
in plans. 相似文献
78.
Philippe Pasquier Ramon Hollands Iyad Rahwan Frank Dignum Liz Sonenberg 《Autonomous Agents and Multi-Agent Systems》2011,22(2):249-288
While argumentation-based negotiation has been accepted as a promising alternative to game-theoretic or heuristic-based negotiation,
no evidence has been provided to confirm this theoretical advantage. We propose a model of bilateral negotiation extending
a simple monotonic concession protocol by allowing the agents to exchange information about their underlying interests and
possible alternatives to achieve them during the negotiation. We present an empirical study that demonstrates (through simulation)
the advantages of this interest-based negotiation approach over the more classic monotonic concession approach to negotiation. 相似文献
79.
Potato starch was oxidized with a neutral aqueous bromine solution at seven different levels of molar ratios of bromine/starch (1/40–5/1). The molecular weight distribution of the products obtained was analysed by gel permeation chromatography on two different agarose gels, Sepharose CL-2B and Superose 6. A gradually increased fragmentation of the molecules with increased oxidation level was noticed. Some of the modified samples were debranched and the products obtained were analysed by gel permeation chromatography. For comparison amylose and waxy maize starch were also treated at the 1/20 and 1/5 molar ratios. The results indicate that the amylose is more easily degraded to small fragments than amylopectin during the oxidation process. An enzymatic starch analysis method was applied on the oxidized samples. This method was found suitable for estimating the total content of introduced keto and carboxylic groups into the modified product. 相似文献
80.
V. Bastys I. Pastoriza‐Santos B. Rodríguez‐Gonzlez R. Vaisnoras L.M. Liz‐Marzn 《Advanced functional materials》2006,16(6):766-773
Silver nanoprisms with strong absorption in the near‐IR have been synthesized using a modification of the photoinduced method by illuminating preformed silver seeds under different illumination conditions. Low‐intensity light‐emitting diodes and white light combined with different color filters are used as light sources. The lateral dimensions of the nanoprisms are found to be correlated in a quasilinear fashion with the emission wavelength and the position of the main in‐plane dipole plasmon band. The structural characterization of the Ag nanoparticles, carried out using scanning electron microscopy, transmission electron microscopy (TEM), high‐resolution TEM, and electron diffraction, reveal that the particles are flat and have a single‐crystal face‐centered‐cubic structure. Time‐resolved studies suggest that the nanoprisms are formed by steady consumption of the original Ag seeds with little variation of the aspect ratio after a short induction time. 相似文献