The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties * To whom correspondence should be addressed. Phone, 404-8940292; fax, 404-894-0294; e-mail, mostafa.el-sayed@ chemistry.gatech.edu. † Case Western Reserve UniversitysMillis 2258. ‡ Phone, 216-368-5918; fax, 216-368-3006; e-mail, burda@case.edu. § Georgia Institute of Technology. 1025 Chem. Rev. 2005, 105, 1025−1102

Chemistry and properties of nanocrystals of different shapes.

1. Introduction 20642. Synthesis of Magnetic Nanoparticles 20662.1. Classical Synthesis by Coprecipitation 20662.2. Reactions in Constrained Environments 20682.3. Hydrothermal and High-TemperatureReactions20692.4. Sol-Gel Reactions 20702.5. Polyol Methods 20712.6. Flow Injection Syntheses 20712.7. Electrochemical Methods 20712.8. Aerosol/Vapor Methods 20712.9. Sonolysis 20723. Stabilization of Magnetic Particles 20723.1. Monomeric Stabilizers 20723.1.1. Carboxylates 20733.1.2. Phosphates 20733.2. Inorganic Materials 20733.2.1. Silica 20733.2.2. Gold 20743.3. Polymer Stabilizers 20743.3.1. Dextran 20743.3.2. Polyethylene Glycol (PEG) 20753.3.3. Polyvinyl Alcohol (PVA) 20753.3.4. Alginate 20753.3.5. Chitosan 20753.3.6. Other Polymers 20753.4. Other Strategies for Stabilization 20764. Methods of Vectorization of the Particles 20765. Structural and Physicochemical Characterization 20785.1. Size, Polydispersity, Shape, and SurfaceCharacterization20795.2. Structure of Ferro- or FerrimagneticNanoparticles20805.2.1. Ferro- and Ferrimagnetic Nanoparticles 20805.3. Use of Nanoparticles as Contrast Agents forMRI20825.3.1. High Anisotropy Model 20845.3.2. Small Crystal and Low Anisotropy EnergyLimit20855.3.3. Practical Interests of Magnetic NuclearRelaxation for the Characterization ofSuperparamagnetic Colloid20855.3.4. Relaxation of Agglomerated Systems 20856. Applications 20866.1. MRI: Cellular Labeling, Molecular Imaging(Inﬂammation, Apoptose, etc.)20866.2.

Magnetic Iron Oxide Nanoparticles: Synthesis, Stabilization, Vectorization, Physicochemical Characterizations, and Biological Applications

Nanocrystals are fundamental to modern science and technology. Mastery over the shape of a nanocrystal enables control of its properties and enhancement of its usefulness for a given application. Our aim is to present a comprehensive review of current research activities that center on the shape-controlled synthesis of metal nanocrystals. We begin with a brief introduction to nucleation and growth within the context of metal nanocrystal synthesis, followed by a discussion of the possible shapes that a metal nanocrystal might take under different conditions. We then focus on a variety of experimental parameters that have been explored to manipulate the nucleation and growth of metal nanocrystals in solution-phase syntheses in an effort to generate specific shapes. We then elaborate on these approaches by selecting examples in which there is already reasonable understanding for the observed shape control or at least the protocols have proven to be reproducible and controllable. Finally, we highlight a number of applications that have been enabled and/or enhanced by the shape-controlled synthesis of metal nanocrystals. We conclude this article with personal perspectives on the directions toward which future research in this field might take.

Shape‐Controlled Synthesis of Metal Nanocrystals: Simple Chemistry Meets Complex Physics?

The unprecedented ability of nanometallic (that is, plasmonic) structures to concentrate light into deep-subwavelength volumes has propelled their use in a vast array of nanophotonics technologies and research endeavours. Plasmonic light concentrators can elegantly interface diffraction-limited dielectric optical components with nanophotonic structures. Passive and active plasmonic devices provide new pathways to generate, guide, modulate and detect light with structures that are similar in size to state-of-the-art electronic devices. With the ability to produce highly confined optical fields, the conventional rules for light-matter interactions need to be re-examined, and researchers are venturing into new regimes of optical physics. In this review we will discuss the basic concepts behind plasmonics-enabled light concentration and manipulation, make an attempt to capture the wide range of activities and excitement in this area, and speculate on possible future directions.

/pdf/plasmonics-for-extreme-light-concentration-and-manipulation-25m55spiva.pdf

Plasmonics for extreme light concentration and manipulation.

1. Introduction 2. Theoretical foundations 3. Propagation and focusing of optical fields 4. Spatial resolution and position accuracy 5. Nanoscale optical microscopy 6. Near-field optical probes 7. Probe-sample distance control 8. Light emission and optical interaction in nanoscale environments 9. Quantum emitters 10. Dipole emission near planar interfaces 11. Photonic crystals and resonators 12. Surface plasmons 13. Forces in confined fields 14. Fluctuation-induced phenomena 15. Theoretical methods in nano-optics Appendices Index.

/pdf/principles-of-nano-optics-1hz998yqo8.pdf

Principles of nano-optics

Spatially-resolved imaging of microprocessor power (SIMP) is shown to be a critical tool for measuring temperature and power distributions of a microprocessor under full operating conditions. In this paper, the SIMP technique is applied to the dual-core PowerPCtrade 970MP microprocessor

Power Distribution Measurements of the Dual Core PowerPC/sup TM/ 970MP Microprocessor

Techniques for analysis and prediction of cloud particle distribution and solar radiation are provided. In one aspect, a method for analyzing cloud particle characteristics includes the steps of: (a) collecting meteorological data; (b) calculating solar radiation values using a radiative transfer model based on the meteorological data and blended guess functions of a cloud particle distribution (c) optimizing the cloud particle distribution by optimizing the weight coefficients used for the blended guess functions of the cloud particle distribution based on the solar radiation values calculated in step (b) and measured solar radiation values; (d) training a machine-learning process using the meteorological data collected in step (a) and the cloud particle distribution optimized in step (c) as training samples; and (e) predicting future solar radiation values using forecasted meteorological data and the machine-learning process trained in step (d).

Machine Learning Approach for Analysis and Prediction of Cloud Particle Size and Shape Distribution

Techniques for ultra-sensitive detection are provided. In one aspect, a detection device is provided. The detection device comprises a source; a drain; a nanowire comprising a semiconductor material having a first end clamped to the source and a second end clamped to the drain and suspended freely therebetween; and a gate in close proximity to the nanowire.

Ultra-sensitive detection techniques

A thermal assembly comprising at once a reading-writing-erasing capability. The present invention, accordingly, can realize important advantages of providing dual yet independent capabilities or functionalities for manifesting reading-writing-erasing on the nanometer scale. An illustrative such thermal assembly includes a thermal heater for writing on a media; a temperature sensor capable of monitoring thermal coupling between the sensor and the media; and, a heater element for heating the temperature sensor.

Assembly suitable for reading/writing/erasing information on a media based on thermal coupling

A system includes a plurality of optical sensors located along at least one pipe segment of a rotating arm that pivots around an irrigation area of a field, the plurality of optical sensors continuously monitors soil and vegetation conditions and transmits sensed data to a central computer, and a plurality of in-ground sensors scattered in the irrigation area of the field, the plurality of in-ground sensors continuously monitors soil conditions and transmits sensed data to a plurality of gateway devices located in the rotating arm, the plurality of gateway devices transmits data from the plurality of in-ground sensors to the central computer where data from the plurality of optical sensors and the plurality of in-ground sensors is integrated with external data to determine water and fertilizer needs based on which an irrigation schedule is created.

Hendrik F. Hamann

Papers

Power Distribution Measurements of the Dual Core PowerPC/sup TM/ 970MP Microprocessor

Machine Learning Approach for Analysis and Prediction of Cloud Particle Size and Shape Distribution

Ultra-sensitive detection techniques

Assembly suitable for reading/writing/erasing information on a media based on thermal coupling

Targeted irrigation using a central pivot irrigation system with a sensor network