Due to their unique optical, electronic and catalytic properties, noble metal nanoparticles (NPs) have received considerable interest during the last two decades in fields ranging from materials science to biology to medicine [1-6]. The distinct optical characteristics of such NPs, which make them advantageous for many applications, stem from the surface plasmon resonance (SPR) effect, which has fascinated scientists for centuries. SPR results from the collective coherent oscillation of free electrons in met-als upon exposure to the oscillating electromagnetic fields of incident lights[7-9]. When the dimensions of the metal are reduced to nanometer scale, the electron oscillation is confined to the surface of the NPs. This is referred to as localized surface plasmon resonance (LSPR) and can be observed with UV-Visible spectroscopy. The wavelength at which a plasmon resonance occurs yields a strong com-bined absorption-scattering peak. In 1908, Gustav Mie explained this phenomenon theoretically through his appli-cation of the Maxwell equations to a spherical particle [10]. Furthermore, the LSPR lead to markedly increased optical absorption efficiencies of the NPs, as much as 105-6 times higher than those of photo-absorbing organic dyes [11].
The LSPR wavelengths depend on the size, shape, structure and composition of the plasmonic NPs [12-15]. These variables suggest the potential of tuning the LSPR wavelengths for optimal use in diverse applications through the variation of size, shape, structure and compo-sition of the plasmonic NPs. While Au nanospheres (NSs) exhibit plasmonic resonance wavelength in the visible re-gion, Au NPs in rod shape, silica-gold core-shell NPs (core size larger than 100 nm) and hollow Au NPs all e...
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...this work, we report a systematic investigation of the optical properties of several types of Au NPs and their hybrid ones with IO core using DDA calculation. These NPs include Au nanospheres (Au NS), Au nanorods (Au NRs), Au nanotetrahedron (Au NTH), hollow Au NSs, IO-Au core-shell NSs, IO-Au core-shell NPs with polymer gap, IO-Au core-shell NRs and IO-Au core-shell NTHs with spherical IO cores. These studies provide an in-depth un-derstanding of the effect of size, shape and structure on the optical extinction spectra of solid and hybrid core-shell NPs. New insights have been added to the classic Au NRs compared with previous studies. Dramatic effects of the polymer gap and the shape have been found on the LSPR wavelength of IO-Au core-shell NPs. Our studies would greatly facilitate the development of IO-Au core-shell NPs for medical and material applications.
Moderata Fonte’s Venetian ladies debated the worth of women while cavorting in their fictional garden in 1605; Tempel Anneke met her unhappy fate in the 1660s. The seemingly enlightened and forward-looking feminist attitudes articulated in Fonte's text were absent from the Brunswick courtroom where the allegations against Tempel Anneke eventually brought about her death. The two accounts illustrate the differences in the attitudes towards women between European states during the 17th century. The differences are technically religiously based, however, they deal with the differences of the specific regional factors of the areas discussed. The differences explain why the attitudes of Fonte’s ladies and the persecutors of Tempel coexisted in roughly the same era. Fonte's ladies are Italian Catholics, and Anna's neighbors are German Protestants, therefore, the ideals of women are varied based on religious experience. Additionally, the theory of reason of state that came about with the consolidation of authority consisted of centralization and secularism that subordinated the social role ...
[24] Chen PC, Mwakwari SC, Oyelere AK. Gold nanoparticles: from nanomedicine to nanosensing. Nanotechnol Sci Appl 2008; 1: 45–66.
All DCM (Discovering a Christian Mind) classes at Calvin read Cornelius Plantinga Jr.’s Engaging God’s World, which discusses why it is valuable to aim to live Christ-like in today’s world. In his book Plantinga explains basic Christian beliefs and Reformed doctrines by highlighting God’s creation, the fall, and human redemption by Jesus’ death on a cross. The ideas of creation, fall, and redemption are displayed by the actions of male protagonists in three major plays: The Tempest by William Shakespeare, The Glass Menagerie by Tennessee Williams, and Death of a Salesman by Arthur Miller.
Motl, N. E., Smith, A. F., DeSantis, C. J., & Skrabalak, S. E. (2014). Engineering plasmonic metal colloids through composition and structural design. Chemical Society Reviews.
23. S. Alwarappan, S. Boyapalle, A. Kumar, C.-Z. Li and S. Mohapatra, J. Phys. Chem. C, 2012, 116, 6556–6559
Nazir et al. "Nanomaterials in Combating Cancer." Nanomedjournal.com. Elsevier Inc., 22 July 2013. Web. 2 Jan. 2014. .
Xu, F., Piett, C., Farkas, S., Qazzaz, M., & Syed, N. I. (2013). Silver nanoparticles
Surface plasmon resonance sensor is a promising optical sensor. In 1902, Wood discovered that there are loss of small area in the spectrum after the light beam passed through a grating[4]. This discovery has been intensified by many researchers. Until 1971, Kretschmann used a prism as a substrate and covered its bottom with thick metal film to achieve SPR detection [5]. Thereafter, SPR technology achieved great development. According to Liu and his colleagues in 2013, this prism based SPR sensor has been used in surface analysis, as well as chemical and biology detection. In 1993, Jorgenson and his colleagues were able to use optical fibers as the guide medium of light in SPR detection [6]. Then, many reports rapidly increased in the chemical, biological, environment and medicine fields [7-16].
Inorganic nanowires often exhibit unique property that is useful for future applications. As the sizes of materials are decreasing down to the nanoscale level, the physical structure and chemical properties of nanomaterials are also diverging away from its bulk form [N&N]. Nanowires display the quantum confinement effect which describes the energy level of electrons as discrete unit [N&N]. For example, the transfer of electrons from the valence band to the conducting band requires a specific amount of energy [N&N]. Additionally, the surface area to volume ratio increases as the particles gets smaller [N&N]. This property supports many of the future application of TiO2 nanowires that requires a large surface a...
The ability to modify the external parts of porphyrins extending their conjugated core or even coordinating metals or metalloids to induce a change in their conductivity and energy gap between HOMO and LUMO makes this type of molecules perfect candidates for molecular electronics. Moreover, their high molar absorption coefficients, their robustness, their tendency to act as donors and the aforementioned ability to tune their energy gap allow them to play an important role as electron donors in Organic Solar Cells.
The reduction of silver ions was observed using spectroscopic analysis by measuring the spectral wave length change and observed a peak at 430nm. The spectrum produced due to the bioreduction of silver ions and its Surface Plasmon Resonance (SPR) at room temperature was observed using Thermo UV10 Spectrophotometer at a band width of 1nm.
In the 1970s, scientists discovered the SERS phenomenon, in which pyridine molecules were absorbed onto a roughened silver surface, resulting in a significant enhancement of the Raman signals [2]. It was found that SERS can enhance the scattering effect markedly, even up to 1014 times the common Raman signal [3], which overcame the low sensitivity of the common Raman technique. The enhancement is mainly owing to the amplification of the light resulting from the excitation of localized surface plasmon resonances
Over the past decades Nanoscience and nanotechnology is a springing up field of research interspersing material science and bionanoscience. Nanotechnology is an expanding area use to deal with materials in nano dimensions. Nanotechnology is the study and application of small object which can be used across all fields such as chemistry, biology, physics, material science and engineering. As the name indicates nano means a billionth or 10-9 unit. Its size range usually from 1-100nm (Nair et al., 2010). Nano size particles are quite unique in nature because nano size increase surface to volume ratio. So the main aim to study its minute size is to trigger chemical activity with distinct crystallography that increases the surface area (Sinha et al., 2009). Thus in recent years much research is going on metallic nanoparticle and its properties like catalyst, sensing to optics, antibacterial activity, data storage capacity and its use in agricultural productivity (Nair et al., 2010 & Sharma et al., 2009).