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Journal articles on the topic 'Ultrasmall structures'

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Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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1

Hung, K. M., and G. Y. Wu. "Noise characteristics of ultrasmall resonant-tunneling structures." Physical Review B 48, no. 19 (November 15, 1993): 14687–89. http://dx.doi.org/10.1103/physrevb.48.14687.

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2

He, Yang, Jin-Cheng Liu, Langli Luo, Yang-Gang Wang, Junfa Zhu, Yingge Du, Jun Li, Scott X. Mao, and Chongmin Wang. "Size-dependent dynamic structures of supported gold nanoparticles in CO oxidation reaction condition." Proceedings of the National Academy of Sciences 115, no. 30 (July 9, 2018): 7700–7705. http://dx.doi.org/10.1073/pnas.1800262115.

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Gold (Au) catalysts exhibit a significant size effect, but its origin has been puzzling for a long time. It is generally believed that supported Au clusters are more or less rigid in working condition, which inevitably leads to the general speculation that the active sites are immobile. Here, by using atomic resolution in situ environmental transmission electron microscopy, we report size-dependent structure dynamics of single Au nanoparticles on ceria (CeO2) in CO oxidation reaction condition at room temperature. While large Au nanoparticles remain rigid in the catalytic working condition, ultrasmall Au clusters lose their intrinsic structures and become disordered, featuring vigorous structural rearrangements and formation of dynamic low-coordinated atoms on surface. Ab initio molecular-dynamics simulations reveal that the interaction between ultrasmall Au cluster and CO molecules leads to the dynamic structural responses, demonstrating that the shape of the catalytic particle under the working condition may totally differ from the shape under the static condition. The present observation provides insight on the origin of superior catalytic properties of ultrasmall gold clusters.
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3

Kash, K., A. Scherer, J. M. Worlock, H. G. Craighead, and M. C. Tamargo. "Optical spectroscopy of ultrasmall structures etched from quantum wells." Applied Physics Letters 49, no. 16 (October 20, 1986): 1043–45. http://dx.doi.org/10.1063/1.97466.

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4

Jiang, Xiao Xiao, Feng Wen Wang, Zhen He Ma, Qiong Chan Gu, Jiang Tao Lv, and Guang Yuan Si. "Arbitrary Structures Fabricated by Focused Ion Beam Milling." Advanced Materials Research 661 (February 2013): 66–69. http://dx.doi.org/10.4028/www.scientific.net/amr.661.66.

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Optical components at the nanoscale are crucial for developing photonics and integrated optics. Device with ultrasmall dimensions is of particular importance for nanoscience and electronic technology. Among all the manufacturing tools, the focused ion beam is a critical candidate for machining and processing optical devices at the nanoscale. Here, we experimentally demonstrate the fabrication of nanodevices with arbitrary shapes and different potential applications using focused ion beam techniques.
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5

Jiang, Feng, Ruimin Li, Jianhua Cai, Wei Xu, Anmin Cao, Daiqin Chen, Xing Zhang, Chunru Wang, and Chunying Shu. "Ultrasmall Pd/Au bimetallic nanocrystals embedded in hydrogen-bonded supramolecular structures: facile synthesis and catalytic activities in the reduction of 4-nitrophenol." Journal of Materials Chemistry A 3, no. 38 (2015): 19433–38. http://dx.doi.org/10.1039/c5ta02260f.

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6

Huang, Shengxi, Tian Ming, Yuxuan Lin, Xi Ling, Qifeng Ruan, Tomás Palacios, Jianfang Wang, Mildred Dresselhaus, and Jing Kong. "Ultrasmall Mode Volumes in Plasmonic Cavities of Nanoparticle-On-Mirror Structures." Small 12, no. 37 (August 12, 2016): 5190–99. http://dx.doi.org/10.1002/smll.201601318.

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7

Huang, Tiefan, Guan Sheng, Priyanka Manchanda, Abdul H. Emwas, Zhiping Lai, Suzana Pereira Nunes, and Klaus-Viktor Peinemann. "Cyclodextrin polymer networks decorated with subnanometer metal nanoparticles for high-performance low-temperature catalysis." Science Advances 5, no. 11 (November 2019): eaax6976. http://dx.doi.org/10.1126/sciadv.aax6976.

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The synthesis of support materials with suitable coordination sites and confined structures for the controlled growth of ultrasmall metal nanoparticles is of great importance in heterogeneous catalysis. Here, by rational design of a cross-linked β-cyclodextrin polymer network (CPN), various metal nanoparticles (palladium, silver, platinum, gold, and rhodium) of subnanometer size (<1 nm) and narrow size distribution are formed via a mild and facile procedure. The presence of the metal coordination sites and the network structure are key to the successful synthesis and stabilization of the ultrasmall metal nanoparticles. The as-prepared CPN, loaded with palladium nanoparticles, is used as a heterogeneous catalyst and shows outstanding catalytic performance in the hydrogenation of nitro compounds and Suzuki-Miyaura coupling reaction under mild conditions. The CPN support works synergistically with the metal nanoparticles, achieving high catalytic activity and selectivity. In addition, the catalytic activity of the formed catalyst is controllable.
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8

Kuhn, Emanuele, Andrew S. Ichimura, Vivian Peng, Christian H. Fritsen, Gareth Trubl, Peter T. Doran, and Alison E. Murray. "Brine Assemblages of Ultrasmall Microbial Cells within the Ice Cover of Lake Vida, Antarctica." Applied and Environmental Microbiology 80, no. 12 (April 11, 2014): 3687–98. http://dx.doi.org/10.1128/aem.00276-14.

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ABSTRACTThe anoxic and freezing brine that permeates Lake Vida's perennial ice below 16 m contains an abundance of very small (≤0.2-μm) particles mixed with a less abundant population of microbial cells ranging from >0.2 to 1.5 μm in length. Fluorescent DNA staining, electron microscopy (EM) observations, elemental analysis, and extraction of high-molecular-weight genomic DNA indicated that a significant portion of these ultrasmall particles are cells. A continuous electron-dense layer surrounding a less electron-dense region was observed by EM, indicating the presence of a biological membrane surrounding a cytoplasm. The ultrasmall cells are 0.192 ± 0.065 μm, with morphology characteristic of coccoid and diplococcic bacterial cells, often surrounded by iron-rich capsular structures. EM observations also detected the presence of smaller unidentified nanoparticles of 0.020 to 0.140 μm among the brine cells. A 16S rRNA gene clone library from the brine 0.1- to 0.2-μm-size fraction revealed a relatively low-diversity assemblage ofBacteriasequences distinct from the previously reported >0.2-μm-cell-size Lake Vida brine assemblage. The brine 0.1- to 0.2-μm-size fraction was dominated by theProteobacteria-affiliated generaHerbaspirillum,Pseudoalteromonas, andMarinobacter. Cultivation efforts of the 0.1- to 0.2-μm-size fraction led to the isolation ofActinobacteria-affiliated generaMicrobacteriumandKocuria. Based on phylogenetic relatedness and microscopic observations, we hypothesize that the ultrasmall cells in Lake Vida brine are ultramicrocells that are likely in a reduced size state as a result of environmental stress or life cycle-related conditions.
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9

Odanaka, S. "Multidimensional Discretization of the Stationary Quantum Drift-Diffusion Model for Ultrasmall MOSFET Structures." IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems 23, no. 6 (June 2004): 837–42. http://dx.doi.org/10.1109/tcad.2004.828128.

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10

Ma, Kai, Katherine A. Spoth, Ying Cong, Duhan Zhang, Tangi Aubert, Melik Z. Turker, Lena F. Kourkoutis, Eduardo Mendes, and Ulrich Wiesner. "Early Formation Pathways of Surfactant Micelle Directed Ultrasmall Silica Ring and Cage Structures." Journal of the American Chemical Society 140, no. 50 (November 20, 2018): 17343–48. http://dx.doi.org/10.1021/jacs.8b08802.

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11

Méndez-Vilas, A., L. Labajos-Broncano, J. Perera-Núñez, and M. L. González-Martín. "Are the Soft, Liquid-Like Structures Detected around Bacteria by Ambient Dynamic Atomic Force Microscopy Capsules?" Applied and Environmental Microbiology 77, no. 9 (March 11, 2011): 3102–14. http://dx.doi.org/10.1128/aem.01262-10.

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ABSTRACTHigh-resolution imaging of bacterial capsules by microscopy is of paramount importance in microbiology due to their role in pathogenesis. This is, however, quite a challenging task due to their delicate nature. In this context, recent reports have claimed successful exploitation of the capacity of atomic force microscopy (AFM) for imaging of extremely deformable (even liquid) surfaces under ambient conditions to detect bacterial capsules in the form of tiny amounts of liquid-like substances around bacteria. In order to further explore this supposed capacity of AFM, in this work, three staphylococcal strains have been scrutinized for the presence of capsules using such an AFM-based approach with a phosphate buffer and water as the suspending liquids. Similar results were obtained with the three strains. AFM showed the presence of liquid-like substances identical to those attributed to bacterial capsules in the previous literature. Extensive imaging and chemical analysis point out the central role of the suspending liquid (buffer) in the formation of these substances. The phenomenon has been reproduced even by using nonliving particles, a finding that refutes the biological origin of the liquid-like substances visualized around the cells. Deliquescence of major components of biological buffers, such as K2HPO4, CaCl2, or HEPES, is proposed as the fundamental mechanism of the formation of these ultrasmall liquid-like structures. Such an origin could explain the high similarity of our results obtained with three very different strains and also the high similarity of these results to others reported in the literature based on other bacteria and suspending liquids. Finally, possible biological/biomedical implications of the presence of these ultrasmall amounts of liquids wrapping microorganisms are discussed.
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12

Szeifert, Johann M., Johann M. Feckl, Dina Fattakhova-Rohlfing, Yujing Liu, Vit Kalousek, Jiri Rathousky, and Thomas Bein. "Ultrasmall Titania Nanocrystals and Their Direct Assembly into Mesoporous Structures Showing Fast Lithium Insertion." Journal of the American Chemical Society 132, no. 36 (September 15, 2010): 12605–11. http://dx.doi.org/10.1021/ja101810e.

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13

Nguyen, Kiet A., Ruth Pachter, and Paul N. Day. "Computational Prediction of Structures and Optical Excitations for Nanoscale Ultrasmall ZnS and CdSe Clusters." Journal of Chemical Theory and Computation 9, no. 8 (July 8, 2013): 3581–96. http://dx.doi.org/10.1021/ct4001944.

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14

Tehrani, Mehran, Thusitha Nanda Bandara Etampawala, Mark Dadmun, and Mohammad Abir Hossain. "Resolving Hierarchical Structures in Carbon Nanotube Networks Using Small- and Ultrasmall-Angle Neutron Scattering." Journal of Physical Chemistry C 121, no. 40 (October 3, 2017): 22442–51. http://dx.doi.org/10.1021/acs.jpcc.7b06114.

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15

Vasileska, Dragica, Richard Akis, Irena Knezevic, Srđan N. Miličić, Shaikh S. Ahmed, and David K. Ferry. "Role of quantization effects in the operation of ultrasmall MOSFETs and SOI device structures." Microelectronic Engineering 63, no. 1-3 (August 2002): 233–40. http://dx.doi.org/10.1016/s0167-9317(02)00630-5.

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16

Yang, Shulin, Yongming Hu, Shengfu Wang, Haoshuang Gu, and Yu Wang. "Phase Transition and Optical Properties for Ultrathin KNbO3Nanowires." Advances in Condensed Matter Physics 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/567420.

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Fascicular KNbO3nanowires with tetragonal perovskite structures and ultrasmall diameters are synthesized by hydrothermal route at about 150°C for 24 hours. The concentrations of medium alkalinity have influenced phase structures and the final morphologies of the products significantly by modifying the conditions in process. The as-prepared KNbO3nanowires exhibit three phase transitions at about 343, 454.7, and 623 K as the temperature increases from 250 to 700 K. The band gap is about 3.78 eV for KNbO3nanowires. Photoluminescence study at room temperature reveals two visible light emission bands peaking at ~551 and 597 nm, respectively, which may be due to the oxygen vacancies, site niobium (occupy the location of Nb), and antisite niobium (occupy the location of K) in KNbO3nanowires.
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17

Li, Qi, John Kulikowski, David Doan, Ottman A. Tertuliano, Charles J. Zeman, Melody M. Wang, George C. Schatz, and X. Wendy Gu. "Mechanical nanolattices printed using nanocluster-based photoresists." Science 378, no. 6621 (November 18, 2022): 768–73. http://dx.doi.org/10.1126/science.abo6997.

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Natural materials exhibit emergent mechanical properties as a result of their nanoarchitected, nanocomposite structures with optimized hierarchy, anisotropy, and nanoporosity. Fabrication of such complex systems is currently challenging because high-quality three-dimensional (3D) nanoprinting is mostly limited to simple, homogeneous materials. We report a strategy for the rapid nanoprinting of complex structural nanocomposites using metal nanoclusters. These ultrasmall, quantum-confined nanoclusters function as highly sensitive two-photon activators and simultaneously serve as precursors for mechanical reinforcements and nanoscale porogens. Nanocomposites with complex 3D architectures are printed, as well as structures with tunable, hierarchical, and anisotropic nanoporosity. Nanocluster-polymer nanolattices exhibit high specific strength, energy absorption, deformability, and recoverability. This framework provides a generalizable, versatile approach for the use of photoactive nanomaterials in additive manufacturing of complex systems with emergent mechanical properties.
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18

Kamai, Hiroki, and Yan Xu. "Fabrication of Ultranarrow Nanochannels with Ultrasmall Nanocomponents in Glass Substrates." Micromachines 12, no. 7 (June 30, 2021): 775. http://dx.doi.org/10.3390/mi12070775.

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Nanofluidics is supposed to take advantage of a variety of new physical phenomena and unusual effects at nanoscales typically below 100 nm. However, the current chip-based nanofluidic applications are mostly based on the use of nanochannels with linewidths above 100 nm, due to the restricted ability of the efficient fabrication of nanochannels with narrow linewidths in glass substrates. In this study, we established the fabrication of nanofluidic structures in glass substrates with narrow linewidths of several tens of nanometers by optimizing a nanofabrication process composed of electron-beam lithography and plasma dry etching. Using the optimized process, we achieved the efficient fabrication of fine glass nanochannels with sub-40 nm linewidths, uniform lateral features, and smooth morphologies, in an accurate and precise way. Furthermore, the use of the process allowed the integration of similar or dissimilar material-based ultrasmall nanocomponents in the ultranarrow nanochannels, including arrays of pockets with volumes as less as 42 zeptoliters (zL, 10−21 L) and well-defined gold nanogaps as narrow as 19 nm. We believe that the established nanofabrication process will be very useful for expanding fundamental research and in further improving the applications of nanofluidic devices.
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19

Shin, Young Jae, Yi-Kuei Wu, and L. Jay Guo. "Nanoimprinting ultrasmall and high-aspect-ratio structures by using rubber-toughened UV cured epoxy resist." Nanotechnology 24, no. 25 (May 24, 2013): 255302. http://dx.doi.org/10.1088/0957-4484/24/25/255302.

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20

Lv, Jiangtao, Ming Zhou, Qiongchan Gu, Xiaoxiao Jiang, Yu Ying, and Guangyuan Si. "Metamaterial Lensing Devices." Molecules 24, no. 13 (July 4, 2019): 2460. http://dx.doi.org/10.3390/molecules24132460.

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In recent years, the development of metamaterials and metasurfaces has drawn great attention, enabling many important practical applications. Focusing and lensing components are of extreme importance because of their significant potential practical applications in biological imaging, display, and nanolithography fabrication. Metafocusing devices using ultrathin structures (also known as metasurfaces) with superlensing performance are key building blocks for developing integrated optical components with ultrasmall dimensions. In this article, we review the metamaterial superlensing devices working in transmission mode from the perfect lens to two-dimensional metasurfaces and present their working principles. Then we summarize important practical applications of metasurfaces, such as plasmonic lithography, holography, and imaging. Different typical designs and their focusing performance are also discussed in detail.
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21

Chen, Cheng, Meixiao Wang, Jinxiong Wu, Huixia Fu, Haifeng Yang, Zhen Tian, Teng Tu, et al. "Electronic structures and unusually robust bandgap in an ultrahigh-mobility layered oxide semiconductor, Bi2O2Se." Science Advances 4, no. 9 (September 2018): eaat8355. http://dx.doi.org/10.1126/sciadv.aat8355.

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Semiconductors are essential materials that affect our everyday life in the modern world. Two-dimensional semiconductors with high mobility and moderate bandgap are particularly attractive today because of their potential application in fast, low-power, and ultrasmall/thin electronic devices. We investigate the electronic structures of a new layered air-stable oxide semiconductor, Bi2O2Se, with ultrahigh mobility (~2.8 × 105cm2/V⋅s at 2.0 K) and moderate bandgap (~0.8 eV). Combining angle-resolved photoemission spectroscopy and scanning tunneling microscopy, we mapped out the complete band structures of Bi2O2Se with key parameters (for example, effective mass, Fermi velocity, and bandgap). The unusual spatial uniformity of the bandgap without undesired in-gap states on the sample surface with up to ~50% defects makes Bi2O2Se an ideal semiconductor for future electronic applications. In addition, the structural compatibility between Bi2O2Se and interesting perovskite oxides (for example, cuprate high–transition temperature superconductors and commonly used substrate material SrTiO3) further makes heterostructures between Bi2O2Se and these oxides possible platforms for realizing novel physical phenomena, such as topological superconductivity, Josephson junction field-effect transistor, new superconducting optoelectronics, and novel lasers.
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22

Fujisawa, T., and M. Koshiba. "Theoretical investigation of ultrasmall polarization-insensitive 1/spl times/2 multimode interference waveguides based on sandwiched structures." IEEE Photonics Technology Letters 18, no. 11 (June 2006): 1246–48. http://dx.doi.org/10.1109/lpt.2006.875058.

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23

Ter-Martirosyan, Armen, Vitalii Sidorov, and Evgeny Sobolev. "Dynamic Properties of Soil Cements for Numerical Modelling of the Foundation’s Basis Transformed under the Technology of Deep Soil Mixing: A Determination Method." Buildings 12, no. 7 (July 16, 2022): 1028. http://dx.doi.org/10.3390/buildings12071028.

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This research investigates the mechanical properties of soil-cement specimens ranging from ultrasmall to large values of shear strain at dynamic loading. The nonlinear behavior of soil cement exposed to dynamic loading in a wide range of changing shear strains was examined on the basis of two mechanical models. All soil-cement specimens were collected from under an existing building and modified with deep soil mixing (DSM.). Soil-cement samples were examined using low-amplitude oscillations in the resonant column and the dynamic triaxial compression method. Additionally, the stress–strain state for modified footings exposed to dynamic loading, and the approximation of soil stiffness and damping coefficient was analyzed. Dependencies on the basis of the resilient elastic models of Ramberg–Osgood and Hardin–Drnevich are proposed for application. Results reveal that the empirical graphs of the dependency soil stiffness–shear strain based on various methods exhibited the distinctive S-shape of decreased stiffness. The stiffness of the soil cement was reduced by 50% of the maximal value at shear strains of the 10−3 decimal order. The method presented in this study enables the drawing of stiffness change and damping–shear strain dependency where the range of shear strains changes from ultrasmall to large strains. The normalized modulus of shearing and the damping coefficient on shear strains for soil cement could be obtained under the proposed method. This method can be used for the preliminary calculations of structures on the footing modified by mathematical modelling or when field research data from site investigation are not available.
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24

Moradian, Mohsen, and Masoomeh Nazarabi. "Ultrasmall Monodisperse NiO Nanocrystals as a Heterogeneous Catalyst for the A3-Coupling Reaction Toward Propargylamines." Acta Chimica Slovenica 68, no. 3 (September 15, 2021): 594–603. http://dx.doi.org/10.17344/acsi.2020.6412.

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Ultrasmall monodisperse NiO nanoparticles (7–9 nm) were synthesized through thermal decomposition of Ni-oleylamine complexes. Various measurement techniques involving Fourier-transform infrared spectroscopy (FT-IR), diffuse reflectance UV-Vis spectroscopy (DRS), X-ray diffractometer (XRD), energy dispersive X-ray analysis (EDX), scanning electron microscopy (SEM), dynamic light scattering technique (DLS), and vibrating sample magnetometer (VSM) were employed to characterize the synthesized catalyst. Propargylamine derivatives were synthesized with aldehydes, terminal alkynes and primary amines through a one-pot A3-coupling reaction by using a 3 mol% amount of the NiO nanocrystals at 80 °C under solvent-free conditions with good to excellent yields. The structures of the products were confirmed by 1H and 13C NMR spectroscopy. The catalyst presents many advantages including being environmentally friendly, easy to recover, reusable, stable, and applicable to a wide variety of substrates, as well as having cost-effective preparation.
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25

Petroff, P. M., and G. Medeiros-Ribeiro. "Three-Dimensional Carrier Confinement in Strain-Induced Self-Assembled Quantum Dots." MRS Bulletin 21, no. 4 (April 1996): 50–54. http://dx.doi.org/10.1557/s088376940003534x.

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Recent technological and materials advances in semiconductors have brought about the possibility of producing heterostructures within which carriers are confined to an ultrasmall region of space (a few thousand atoms) by a potential barrier. When the dimensions of the confining potential are smaller than the electron wavelength (a few tens of nanometers), the semiconductor electronic and optical properties are drastically altered. In these so-called quantum structures, carrier energy levels are quantized and their energy depends on the confining-potential dimensions and magnitude.Some of these quantum structures have already found technological applications. For example the quantum-well (QW) semiconductor laser is part of every CD player. It is also widely used as the light source for intercontinental optical communications. The carrier confining potential in this case is provided by two wider bandgap semiconductor layers sandwiching a thin (3–20 nm) smaller bandgap semiconductor film. The carriers have two degrees of freedom within the QW. The QWs are grown by epitaxial deposition on a crystalline substrate. The substrate may or may not be lattice-matched with the epitaxial film. In some instances, a small lattice mismatch may be required to obtain the desired band-gap value for the QW material. These are the so-called pseudomorphically strained QW structures and devices.
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26

Roberg, Karin, and Karin Öllinger. "A Pre-embedding Technique for Immunocytochemical Visualization of Cathepsin D in Cultured Cells Subjected to Oxidative Stress." Journal of Histochemistry & Cytochemistry 46, no. 3 (March 1998): 411–18. http://dx.doi.org/10.1177/002215549804600316.

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We describe a pre-embedding immunocytochemical method for visualization of the lysosomal enzyme cathepsin D in cultured cells. The protein was demonstrated at both light and electron microscopic levels by neutral-pH silver enhancement of ultrasmall (0.8-nm) gold particles conjugated to the antibodies. The best morphological preservation and the highest labeling density were achieved by initial fixation for 20 min at 4C in 4% paraformaldehyde (PFA) and 0.05% glutaraldehyde (GA) in 0.15 M sodium cacodylate buffer, followed by permeabilization in sodium borohydride. Three cell types were used: human foreskin fibroblasts, histocytic lymphoma (J-774) cells, and primary rat heart myocytes. In all three, cathepsin D was demonstrated in lysosome-like structures. The rat heart myocytes were also exposed to the redox cycling substance naphthazarin (5,8-dihydroxy-1,4-naph-thoquinone) to induce oxidative stress. This was done for such a short period of time that the cells initially did not show any signs of morphological damage and retained normal plasma membrane stability, although an early and clear redistribution of cathepsin D from membrane-bound structures to the cytosol was apparent. This redistribution was followed by cell degeneration and, eventually, by cell death.
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27

Zeng, Chenjie. "Precision at the nanoscale: on the structure and property evolution of gold nanoclusters." Pure and Applied Chemistry 90, no. 9 (September 25, 2018): 1409–27. http://dx.doi.org/10.1515/pac-2018-0511.

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Abstract Chemists are often regarded as “architects”, who are capable of building up complex molecular structures in the ultrasmall-dimensional world. However, compared with organic chemistry, nanochemistry – which deals with nanoparticles in the size range from 1 to 100 nm – is less precise in terms of synthesis, composition, and structure. Such an imprecise nature of nanochemistry has impeded an in-depth understanding as well as rational control of structures and properties of nanomaterials. Motivated by this, thiolate-protected gold nanoclusters (denoted as Aun(SR)m) have recently emerged as a paradigm of atomically precise nanomaterials, in which all the nanoparticles are identical to each other with the same number of core atoms (n) and surface ligands (m) as well as the atomic arrangement. In this review, we provide a demonstration of how the precise nature of Aun(SR)m nanoclusters allows one to understand, decipher and discover some important, enigmatic and intriguing issues and phenomena in nanoscience, including (i) a precise nanoscale transformation reaction induced by surface ligand exchange, (ii) the total structures of crystalline metal phases and the self-assembled surface monolayers, (iii) the periodicities and quantum confinement in nanoclusters and (iv) the emergence of hierarchical complexity in the entire nanoparticle system. We expect that such an in-depth understanding will eventually lead to the rational design and precise engineering of complex architectures at the nanoscale.
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28

Di, Jun, Jiexiang Xia, Mengxia Ji, Bin Wang, Sheng Yin, Hui Xu, Zhigang Chen, and Huaming Li. "Carbon Quantum Dots Induced Ultrasmall BiOI Nanosheets with Assembled Hollow Structures for Broad Spectrum Photocatalytic Activity and Mechanism Insight." Langmuir 32, no. 8 (February 12, 2016): 2075–84. http://dx.doi.org/10.1021/acs.langmuir.5b04308.

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29

Jiang, Yihui, Le Han, Yingqin Xu, Fei Cao, Xiang Du, Fei Han, Lei Cai, and Jialin Zhu. "Arc erosion behaviour of in-situ TiB2/Cu composites with a three-dimensional network structure." Materials Research Express 9, no. 4 (April 1, 2022): 046503. http://dx.doi.org/10.1088/2053-1591/ac6091.

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Abstract Copper matrix composites (CMCs) with tailored heterogeneous structures at the mesoscopic scale are promising candidates for electrical contact materials. In this work, CMCs reinforced by an in situ formed three-dimensional network of TiB2 particles were synthesized from Cu, Ti and B powder mixtures by reactive hot-pressing. The arc erosion behaviour of the fabricated CMCs was investigated by an electrical contact test. The distribution state of in situ TiB2 depends on the particle size of the Cu powder. The critical size for forming a continuous network in 3 wt%TiB2/Cu composites is estimated to be 24 μm. Once the continuous network is formed in CMCs, the arc energy and duration suddenly change to ultrasmall and stable values, and the erosion area and total mass loss after 5000 cycles of the contact test remarkably decrease. The results indicate that the CMCs reinforced by in situ networks of TiB2 particles exhibit excellent arc erosion resistance.
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30

Takizawa, Toshihiro, and John M. Robinson. "FluoroNanogold Is a Bifunctional Immunoprobe for Correlative Fluorescence and Electron Microscopy." Journal of Histochemistry & Cytochemistry 48, no. 4 (April 2000): 481–85. http://dx.doi.org/10.1177/002215540004800405.

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We applied a fluorescent ultrasmall immunogold probe, FluoroNanogold (FNG), to immunocytochemistry on ultrathin cryosections. FNG has the properties of both a fluorescent dye-conjugated antibody for fluorescence microscopy and a gold particle-conjugated antibody for electron microscopy. Therefore, this bifunctional immunoprobe permits correlative microscopic observation of the same cell profiles labeled in a single labeling procedure by these two imaging methods. We demonstrate the utility of FNG as a secondary antibody for immunocytochemical labeling of myeloperoxidase (a marker protein for azurophilic granules) in ultrathin cryosectioned human neutrophils. Its detection requires high spatial resolution because neutrophils contain many cytoplasmic granules. There was a one-to-one relationship between fluorescent structures labeled with FNG and organelle profiles labeled with the same silver-enhanced FNG in ultrathin cryosections. Use of FNG immunocytochemistry on ultrathin cryosections is an ideal methodology for highresolution correlative fluorescence and electron microscopy and can provide unique information that may be difficult to obtain with a single imaging regimen.
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31

Renella, Pierangelo, Jennifer Li, Ashley E. Prosper, J. Paul Finn, and Kim-Lien Nguyen. "Ferumoxytol-Enhanced Cardiac Magnetic Resonance Angiography and 4D Flow: Safety and Utility in Pediatric and Adult Congenital Heart Disease." Children 9, no. 12 (November 24, 2022): 1810. http://dx.doi.org/10.3390/children9121810.

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Cardiac magnetic resonance imaging and angiography have a crucial role in the diagnostic evaluation and follow up of pediatric and adult patients with congenital heart disease. Although much of the information required of advanced imaging studies can be provided by standard gadolinium-enhanced magnetic resonance imaging, the limitations of precise bolus timing, long scan duration, complex imaging protocols, and the need to image small structures limit more widespread use of this modality. Recent experience with off-label diagnostic use of ferumoxytol has helped to mitigate some of these barriers. Approved by the U.S. FDA for intravenous treatment of anemia, ferumoxytol is an ultrasmall superparamagnetic iron oxide nanoparticle that has a long blood pool residence time and high relaxivity. Once metabolized by macrophages, the iron core is incorporated into the reticuloendothelial system. In this work, we aim to summarize the evolution of ferumoxytol-enhanced cardiovascular magnetic resonance imaging and angiography and highlight its many applications for congenital heart disease.
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32

Helms, C. R. "Techniques for Materials Microanalysis." MRS Bulletin 12, no. 6 (September 1987): 22–25. http://dx.doi.org/10.1557/s0883769400067178.

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The science and technology of ultrasmall three-dimensional materials systems has been developing rapidly the last 20 years or so. Catalysts, coatings, composites, as well as electronic device structures—all rely on materials properties on an atomic scale. To develop such new materials and understand the chemical and physical properties that determine their unique behavior, we also require analytical tools with atomic level spatial resolution and at the same time the desired measurement capability. This need, along with extensive scientific interest in the fundamental chemical and physical properties of free surfaces, has led to the continued development of microanalytical chemical analysis techniques over the past 20 years. Most readers will be familiar with many of these techniques with acronyms such as AES, XPS, RBS, SIMS, ESCA, etc. This issue of the MRS BULLETIN will review some recent advances in the development of these techniques as well as introduce new techniques with significant advantages over the older ones.As you can see from the thickness of this issue, it is difficult to cover the entire field in a finite amount of space. This led us to limit the discussion to those microanalytical tools which can easily be applied to the analysis of buried interface structures such as those found in semiconductor devices.
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Xu, Cheng, Zheng Zhou, and Haixiang Han. "Synthesis, Structure, and Optical Properties of a Molecular Cluster Cd4(p-MBT)10." Crystals 12, no. 9 (September 1, 2022): 1236. http://dx.doi.org/10.3390/cryst12091236.

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The creation of atomically precise nanoclusters has become an important research direction in nanoscience, because such nanomaterials can demonstrate unique chemo-physical properties that are significantly different from their corresponding bulk materials. The cause of such disparities lies in their different construction pattern for the atomic structures, in which the bulk materials display a highly symmetric, extended atomic lattice, while the ultrasmall nanoclusters feature low symmetric molecular structures. In this work, we report a new [HNEt3]2[Cd4(SC7H7)10] (denoted as Cd4(p-MBT)10, p-MBT = p-methylbenzene thiolate) nanocluster obtained through a one-pot synthetic pathway, and its atomic structure was revealed by single crystal X-ray diffraction technique. It shows that the molecular structure for Cd4(p-MBT)10 demonstrates the embryonic features of the corresponding bulk CdS. That is, the whole structure is built from four [CdS4] units which are connected to each other by shared corner S atoms. Due to the molecular nature, the structure of Cd4(p-MBT)10 is distorted, which yields two enantiomeric isomers with chiral Cd-S frameworks that co-crystallize into a non-chiral space group. In addition, the electronic structure was characterized by photoluminescence spectroscopy and calculated by density functional theory.
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Li, Zhao-Yu, Wei Zhou, Zheng-Xing Wu, Rong-Ying Zhang, and Tao Xu. "Fabrication of size-controllable ultrasmall-disk electrode: Monitoring single vesicle release kinetics at tiny structures with high spatio-temporal resolution." Biosensors and Bioelectronics 24, no. 5 (January 2009): 1358–64. http://dx.doi.org/10.1016/j.bios.2008.07.073.

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35

Kunz, M., and M. Möller. "Microdomain and inorganic cluster formation in block copolymers of poly(styrene) and poly-(2-vinylpyridine)." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 356–57. http://dx.doi.org/10.1017/s0424820100153750.

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Selforganization of polymer molecules into ordered supramolecular structures provides a general route for the preparation of materials with new optical, electrical and mechanical properties. In the present paper we we report on glassy diblock copolymers of poly(styrene) and poly(2-vinylpyridine) where the poly(2-vinylpyridine) block was modified by quaternization and by coordination to various transition metal salts. Electron spectroscopic imaging (ESI) and electron energy loss spectroscopy (EELS) were used to localize and to identify the different phases and elements. It has been studied whether the different systems can be used for the formation and stabilization of ultrasmall clusters of inorganic semiconductors.Diblock copolymers of nearly monodisperse molecular weight were synthisized by sequential polymerization of styrene and 2-vinylpyridine. Quaternization with methyliodine resulted in formation of salt groups. Bulk materials were obtained by slow solvent evaporation at elevated temperatures. Ultramicrotomed specimens were examined with a ZEISS CEM 902 operated at 80 kV. An integrated electron energy loss spectrometer allowed to record element specific images as well as electron energy loss spectra.
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36

Baek, Seol, Allison R. Cutri, Donghoon Han, Seung-Ryong Kwon, Julius Reitemeier, Vignesh Sundaresan, and Paul W. Bohn. "Multifunctional nanopore electrode array method for characterizing and manipulating single entities in attoliter-volume enclosures." Journal of Applied Physics 132, no. 17 (November 7, 2022): 174501. http://dx.doi.org/10.1063/5.0101693.

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Structurally regular nanopore arrays fabricated to contain independently controllable annular electrodes represent a new kind of architecture capable of electrochemically addressing small collections of matter—down to the single entity (molecule, particle, and biological cell) level. Furthermore, these nanopore electrode arrays (NEAs) can also be interrogated optically to achieve single entity spectroelectrochemistry. Larger entities such as nanoparticles and single bacterial cells are investigated by dark-field scattering and potential-controlled single-cell luminescence experiments, respectively, while NEA-confined molecules are probed by single molecule luminescence. By carrying out these experiments in arrays of identically constructed nanopores, massively parallel collections of single entities can be investigated simultaneously. The multilayer metal–insulator design of the NEAs enables highly efficient redox cycling experiments with large increases in analytical sensitivity for chemical sensing applications. NEAs may also be augmented with an additional orthogonally designed nanopore layer, such as a structured block copolymer, to achieve hierarchically organized multilayer structures with multiple stimulus-responsive transport control mechanisms. Finally, NEAs constructed with a transparent bottom layer permit optical access to the interior of the nanopore, which can result in the cutoff of far-field mode propagation, effectively trapping radiation in an ultrasmall volume inside the nanopore. The bottom metal layer may be used as both a working electrode and an optical cladding layer, thus, producing bifunctional electrochemical zero-mode waveguide architectures capable of carrying out spectroelectrochemical investigations down to the single molecule level.
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Liu, Liu, Mingliang Jin, Yaocheng Shi, Jiao Lin, Yuan Zhang, Li Jiang, Guofu Zhou, and Sailing He. "Optical integrated chips with micro and nanostructures for refractive index and SERS-based optical label-free sensing." Nanophotonics 4, no. 4 (November 6, 2015): 419–36. http://dx.doi.org/10.1515/nanoph-2015-0015.

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Abstract:Label-free optical biosensing technologies have superior abilities of quantitative analysis, unmodified targets, and ultrasmall sample volume, compared to conventional fluorescence-label-based sensing techniques, in detecting various biomolecules. In this review article, we introduce our recent results in the field of evanescent-wavebased refractive index sensing and surface enhanced Raman scattering (SERS)-based sensing, both of which are promising platforms for label-free optical biosensors. First, silicon-on-insulator (SOI) nanowire waveguide and metallic surface plasmon resonance (SPR)-based refractive index sensing are discussed. In order to improve the detection limit, phase interrogation techniques are introduced to these types of sensors based on prism-coupled SPR and SOI microring resonators. A detection limit in the order of 10−6 refractive index unit is achieved. Detection of 16.7 pM anti-IgG is also demonstrated based on the SPR devices. Second, SERS substrates based on various nanometallic structures are discussed. Metallic nanowire arrays and inverted nanopyramids and grooves with a thin metal surface are fabricated based on anisotropic wetetching of silicon substrates. Both structures have demonstrated a Raman signal enhancement on the order of 107. In order to improve the extraction efficiency of the Raman signal at a high wave number, a nano-bowtie array substrate is fabricated, which exhibits double resonances at both the excitation wavelength and the desired Raman scattering wavelength. Experimental results have shown that this double-resonance structure can further enhance the received Raman signal, as compared to conventional SERS substrates with only one resonance at the excitation wavelength.
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Yin, Yanlong, Ben Hu, Xiao Yuan, Li Cai, Huile Gao, and Qian Yang. "Nanogel: A Versatile Nano-Delivery System for Biomedical Applications." Pharmaceutics 12, no. 3 (March 23, 2020): 290. http://dx.doi.org/10.3390/pharmaceutics12030290.

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Nanogel-based nanoplatforms have become a tremendously promising system of drug delivery. Nanogels constructed by chemical crosslinking or physical self-assembly exhibit the ability to encapsulate hydrophilic or hydrophobic therapeutics, including but not limited to small-molecule compounds and proteins, DNA/RNA sequences, and even ultrasmall nanoparticles, within their 3D polymer network. The nanosized nature of the carriers endows them with a specific surface area and inner space, increasing the stability of loaded drugs and prolonging their circulation time. Reactions or the cleavage of chemical bonds in the structure of drug-loaded nanogels have been shown to trigger the controlled or sustained drug release. Through the design of specific chemical structures and different methods of production, nanogels can realize diverse responsiveness (temperature-sensitive, pH-sensitive and redox-sensitive), and enable the stimuli-responsive release of drugs in the microenvironments of various diseases. To improve therapeutic outcomes and increase the precision of therapy, nanogels can be modified by specific ligands to achieve active targeting and enhance the drug accumulation in disease sites. Moreover, the biomembrane-camouflaged nanogels exhibit additional intelligent targeted delivery features. Consequently, the targeted delivery of therapeutic agents, as well as the combinational therapy strategy, result in the improved efficacy of disease treatments, though the introduction of a multifunctional nanogel-based drug delivery system.
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39

Buck, Manfred. "(Invited) Coordination Controlled Electrodeposition of Metal Nanostructures." ECS Meeting Abstracts MA2022-01, no. 23 (July 7, 2022): 1145. http://dx.doi.org/10.1149/ma2022-01231145mtgabs.

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It is the combination of features related to surface chemistry, charge transfer, and interfacial energies which makes self-assembled monolayers (SAMs) attractive templates for electrodeposition. However, as in other additive processes such as atomic layer or electroless deposition where SAMs are harnessed for area selective deposition, one is faced with substantial challenges when advancing to the ultrasmall scale. Based on defects in a chemically inert SAM, the established scheme of SAM controlled electrodeposition offers a very convenient way to generate patterns but is only applicable down to the length scale of a few tens of nanometers. The statistical nature of defects does not provide the level of control over the deposition process required to move further towards the bottom range of the nanoscale. For this reason we have been exploring a deposition scheme which builts on features intrinsic to the SAM molecules and, therefore, promises a more precise control over decisive steps in the deposition process.1 The essential point is the paradigm shift from a mushroom like deposition at defects to a deposition via coordinated metal ions using a suitably functionalized SAM. As illustrated in the cartoon, nuclei generated by discharging a two-dimensional layer of ions act as seeds for the deposition from the bulk electrolyte. Yielding layers on top of the SAM, this coordination controlled deposition not only enables a further reduction in lateral dimensions of patterns to below 20 nm but also shifts the percolation threshold, yielding continuous layers at a thickness of about 2 nm. In relation to this the average roughness of below 0.4 nm is substantial and further improvement is needed. Key to this and a further reduction in dimensions is the understanding of the processes determining the seed formation and how these can be controlled by the design of the SAM. Informed by calculations which show a strong interaction between metal atoms and the terminating aromatic unit of the SAM,2 studies of binary layers consisting of coordinating and non-coordinating molecules have been performed. The average size and size distribution of the particles depend on the composition and mixing ratio, and a significant reduction in size to about 2 nm can be achieved, suggested that the diffusion length is reduced and nucleation is promoted in mixed SAMs. The results show that SAMs provide a range of design opportunities through which coordination controlled electrodeposition can be further developed towards ultrasmall structures. 1. Z. She, Z. Yao, H. Ménard, S. Tobish, D. Lahaye, N. R. Champness, M. Buck, Coordination controlled electrodeposition and patterning of layers of palladium/copper nanoparticles on top of a self-assembled monolayer, Nanoscale 11, 13773-13782 (2019). 2. Z. Yao, M. Buck, M. Bühl, A Density Functional Theory Study of Pd Aggregation on a Pyridine-Terminated Self-Assembled Monolayer, Chem. Eur. J. 26, 10555-10563 (2020). Figure 1
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40

Zhang, Chunwu, Wei Hou, Zongjun Sun, and Li Gu. "Research on Ground Settlement Regularity of Soft Rock Tunnel under Ultrasmall Distance." Advances in Civil Engineering 2021 (June 7, 2021): 1–8. http://dx.doi.org/10.1155/2021/9952638.

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During the tunnel construction under the road, the shallower the tunnel depth, the greater the effect of the surface settlement. Thus, to analyze the ground settlement caused by tunnel construction under ultrasmall distance, the research is based on a tunnel in Ningqiang County and uses numerical simulation and measurement to analyze the ground settlement and the effect of reinforcement measures. The research draws the following conclusions. For the ultrasmall distance tunnel under road construction, the combination of pipe shed and advanced small pipe grouting reinforcement measures inhibits the surface settlement. After the advanced small pipe is reinforced, the surface settlement value is reduced by about 25%, and the reinforcement effect is more obvious after the increase of the large pipe shed. The surface settlement value is reduced by about 60%. The surface settlement caused by the excavation of the circular soil accounts for about 50%–60% of the total settlement value, which is for the whole construction. The key processes, which involve the combination of reinforcement measures, focused on the suppression of surface settlement caused by the excavation of the circular soil. After the reinforcement measures, the variation of the settlement groove width was not obvious but the curvature and peak value of the settlement groove is reduced significantly.
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41

Zhao, Wenxiang, Suqin Ci, Xiang Hu, Junxiang Chen, and Zhenhai Wen. "Highly dispersed ultrasmall NiS2 nanoparticles in porous carbon nanofiber anodes for sodium ion batteries." Nanoscale 11, no. 11 (2019): 4688–95. http://dx.doi.org/10.1039/c9nr00160c.

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42

McRae, Reagan, Barry Lai, Stefan Vogt, and Christoph J. Fahrni. "Correlative microXRF and optical immunofluorescence microscopy of adherent cells labeled with ultrasmall gold particles." Journal of Structural Biology 155, no. 1 (July 2006): 22–29. http://dx.doi.org/10.1016/j.jsb.2005.09.013.

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43

Sousa, A. A., M. A. Aronova, Y. C. Kim, L. M. Dorward, G. Zhang, and R. D. Leapman. "On the feasibility of visualizing ultrasmall gold labels in biological specimens by STEM tomography." Journal of Structural Biology 159, no. 3 (September 2007): 507–22. http://dx.doi.org/10.1016/j.jsb.2007.06.006.

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44

Gambe, Jess E., Fabien Remondiere, Olivier Masson, Jenny Jouin, Abid Berghout, and Philippe Thomas. "Synthesis and characterization of ultrasmall zirconia particles preparedvianonhydrolytic route." Acta Crystallographica Section A Foundations and Advances 71, a1 (August 23, 2015): s385—s386. http://dx.doi.org/10.1107/s2053273315094267.

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45

Hu, Min, Dandan Ma, Yuzhong Cheng, Chengcheng Liu, Zhipeng Zhang, Yanjun Cai, Si Wu, and Ruifeng Wang. "Synergistically enhanced upconversion luminescence in Li+-doped core–shell-structured ultrasmall nanoprobes for dual-mode deep tissue fluorescence/CT imaging." Journal of Materials Chemistry B 5, no. 14 (2017): 2662–70. http://dx.doi.org/10.1039/c6tb02976k.

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The development of upconversion luminescence that allows for multimodal imaging in terms of resolution and penetration depth using a single system is attracting increasing interest for use in clinical molecular imaging and diagnostics.
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46

Shakeri, Mina, Hamid Delavari H, Alireza Montazerabadi, and Amin Yourdkhani. "Hyaluronic acid-coated ultrasmall BiOI nanoparticles as a potentially targeted contrast agent for X-ray computed tomography." International Journal of Biological Macromolecules 217 (September 2022): 668–76. http://dx.doi.org/10.1016/j.ijbiomac.2022.07.094.

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47

Sousa, A. A., M. A. Aronova, Y. C. Kim, L. M. Dorward, G. Zhang, and R. D. Leapman. "Reprint of “On the feasibility of visualizing ultrasmall gold labels in biological specimens by STEM tomography” [J. Struct. Biol. 159 (2007) 507–522]." Journal of Structural Biology 161, no. 3 (March 2008): 336–51. http://dx.doi.org/10.1016/s1047-8477(08)00063-4.

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48

Driessen, Daphne A. J. J., Didi J. J. M. de Gouw, Rutger C. H. Stijns, Geke Litjens, Bas Israël, Bart W. J. Philips, John J. Hermans, et al. "Validation of In Vivo Nodal Assessment of Solid Malignancies with USPIO-Enhanced MRI: A Workflow Protocol." Methods and Protocols 5, no. 2 (March 7, 2022): 24. http://dx.doi.org/10.3390/mps5020024.

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Background: In various cancer types, the first step towards extended metastatic disease is the presence of lymph node metastases. Imaging methods with sufficient diagnostic accuracy are required to personalize treatment. Lymph node metastases can be detected with ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI), but this method needs validation. Here, a workflow is presented, which is designed to compare MRI-visible lymph nodes on a node-to-node basis with histopathology. Methods: In patients with prostate, rectal, periampullary, esophageal, and head-and-neck cancer, in vivo USPIO-enhanced MRI was performed to detect lymph nodes suspicious of harboring metastases. After lymphadenectomy, but before histopathological assessment, a 7 Tesla preclinical ex vivo MRI of the surgical specimen was performed, and in vivo MR images were radiologically matched to ex vivo MR images. Lymph nodes were annotated on the ex vivo MRI for an MR-guided pathological examination of the specimens. Results: Matching lymph nodes of ex vivo MRI to pathology was feasible in all cancer types. The annotated ex vivo MR images enabled a comparison between USPIO-enhanced in vivo MRI and histopathology, which allowed for analyses on a nodal, or at least on a nodal station, basis. Conclusions: A workflow was developed to validate in vivo USPIO-enhanced MRI with histopathology. Guiding the pathologist towards lymph nodes in the resection specimens during histopathological work-up allowed for the analysis at a nodal basis, or at least nodal station basis, of in vivo suspicious lymph nodes with corresponding histopathology, providing direct information for validation of in vivo USPIO-enhanced, MRI-detected lymph nodes.
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49

Hahn, Braden. "78511 Synthesis of Novel Core/Shell Polymeric Nanoparticles for Controlled Drug Release." Journal of Clinical and Translational Science 5, s1 (March 2021): 100. http://dx.doi.org/10.1017/cts.2021.657.

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ABSTRACT IMPACT: This work will develop a novel drug delivery system that has improved biocompatibility and controlled release than current systems and allow for customizable loading and drug delivery to unique patient and treatment requirements. OBJECTIVES/GOALS: The goal of my project is a novel hybrid core/shell nanoparticle system for controlling in vivo chemotherapeutic concentration. The current goal is to confirm core and shell polymeric nanoparticle formation via emulsion technique and validate predictive model developed to optimize shell formation efficiency and control shell thickness. METHODS/STUDY POPULATION: Though early results are promising, they are not proof that the desired core/shell structure is being formed via my novel process. I constructed a theoretical model to use to optimize and control the process for precise shell thicknesses. Therefore, the current experimental plan focus is to not only visually confirm the predicted formation of my core/shell design but use these experiments to validate the model. 1.Gel-Suspended SEM: nanoparticles suspended in gel matrix, bisected to reveal inner structure2.Fluorescent Conjugation Microscopy: visually-distinct dyes used to show polymer distribution and validated against the theoretical model predictions.3.Modified Hydrophobic Dye Release: different mixtures of polymers with release showing if previous promising results due to core/shell structure RESULTS/ANTICIPATED RESULTS: As stated, the experiments will confirm the core/shell nanoparticle structure, validate the developed theoretical model, or provide direct evidence against any formation. This core/shell structure is key to the current design for controlling payload release rate and thus in vivo drug concentration. For the gel-suspension experiment, the interior core will be labeled with ultrasmall SPIONs and thus any layers within the particles will be distinct. While this result is qualitative, high magnification fluorescent microscope images will be analyzed using image processing software to determine core/shell formation efficiency and compared to estimated efficiencies from the model. Finally, the mixed release will clarify previous experiments’ release mechanism and either support or disprove shell influence. DISCUSSION/SIGNIFICANCE OF FINDINGS: The significance of this work is twofold: core/shell particles have been proven to provide variable control of release on the micron scale but not yet at the nanoscale, allowing for a circulating, targeted system that can finely control release. The process is also novel for producing this type of structure, at highly consistent quality and size.
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50

Pogosov, W. V. "Thermal suppression of surface barrier in ultrasmall superconducting structures." Physical Review B 81, no. 18 (May 17, 2010). http://dx.doi.org/10.1103/physrevb.81.184517.

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