In a nanoscience lab

The production, observation and manipulation of very small objects is a tour de force, but these objects, which could infiltrate anywhere without being seen, may arouse suspicion. To assess the situation at best, we describe the activity of a nanoscience research institution, some of the methods used there, the spirit of its researchers and their attitude towards risk.Comment: article accept\'e pour publication dans les C.R. Physique. El\'ement d'un dossier 'Nanosciences et nanotechnologies: esp\'erances et inqui\'etudes". D'autres articles de ce dossier, ainsi que la version fran\c{c}aise de cet articles, seront \'egalement soumis \`a HA

Diversity and network coherence as indicators of interdisciplinarity: Case studies in bionanoscience

Interdisciplinary research, nanotechnology, nanoscience, diversity, indicators, network analysis

A Year Abroad: Embracing Life in China

Jim Diamond has embraced the Chinese culture during his sabbatical working with a former student at China\u27s National Center for Nanoscience and Technology

Quench characteristics of a stabilizer-free 2G HTS conductor

The prospect of medium/high field superconducting magnets using second generation (2G) HTS tapes is approaching reality with continued enhancement in the performance of these conductors. While the cryogenic stability and quench propagation are fundamental issues for the design and safe operation of superconducting magnets, there is insufficient understanding and experimental data for 2G HTS conductors, in particular for the high field scenario at low temperature (<77 K) where the current sharing regime is much larger than in low temperature superconductors. The present work includes a systematic characterization of the relevant thermal-electrical properties used for both qualitative discussion and numerical analysis. Direct measurements of one dimensional adiabatic quench initiation and propagation of a stabilizer-free 2G conductor have been carried out with spatial-temporal recording of temperature and voltage following the deposition of varying local heat pulses to the conductor at different temperatures between 30 K and 77 K carrying different transport currents. The minimum quench energy, and the heat generation in the minimum propagation zone (MPZ) have been obtained as a function of temperature and transport current. The results show quench features unique to HTS such as an increasing MPZ with transport current and higher quench energies at lower temperatures. The experimental results are discussed in the context of current sharing over a large temperature range

Solar energy conversion

If solar energy is to become a practical alternative to fossil fuels, we must have efficient ways to convert photons into electricity, fuel, and heat. The need for better conversion technologies is a driving force behind many recent developments in biology, materials, and especially nanoscience

Surface Acoustic Waves in Thin Films Nanometrology

Thin films nanometrology is an emerging field in nanoscience as the synthesis, processing and applications of nanostructured thin films require an in-depth knowledge of their elastic constants. The elastic energy of a surface acoustic wave propagating in a solid medium, is concentrated at the interface between the solid and air (or a sufficiently rarified medium); consequently, high frequency surface acoustic waves with sub-micrometer wavelengths are an extraordinary tool for a qualitative and quantitative elastic characterization of thin films. In this article, a short review is presented to describe the main ultrasound techniques based on surface acoustic waves for thin films characterization and to highlight the probing limits of acoustic nanometrology

Nanoscience and Nano-Technology: Cracking Prodigal Farming

Nano-science coupled with nano-technology has emerged as possible cost-cutting measure to prodigal farming and environmental clean-up operations. It has ushered as a new interdisciplinary field by converging various science disciplines, and is highly relevant to agricultural and food systems. Environmental Protection Agency of USA defined nanotechnology as the understanding and control of matter at dimensions of roughly 1-100 nm, where unique physical properties make novel applications possible. By this definition all soil-clays, many chemicals derived from soil organic matter (SOM), several soil microorganisms fall into this category. Apart from native soil-materials, many new nanotech products are entering into soil system, some of which are used for agricultural production and some others for many other purposes.

Nano-science (also nanotechnology) has found applications in controlling release of nitrogen, characterization of soil minerals, studies of weathering of soil minerals and soil development, micro-morphology of soils, nature of soil rhizosphere, nutrient ion transport in soil-plant system, emission of dusts and aerosols from agricultural soil and their nature, zeoponics, and precision water farming. In its stride, nanotechnology converges soil mineralogy with imaging techniques, artificial intelligence, and encompass bio molecules and polymers with microscopic atoms and molecules, and macroscopic properties (thermodynamics) with microscopic properties (kinetics, wave theory, uncertainty principles, etc.), to name a few. 

Some of the examples include clinoloptolite and other zeolite based substrates, and Fe-, Mn-, and Cu- substituted synthetic hydroxyapatites that have made it possible to grow crops in space stations and at Antarctica. This has eliminated costs of repeated launching of space crafts. A disturbing fact is that the fertilizer use efficiency is 20-50 percent for nitrogen, and 10-25 percent for phosphorus (<1% for rock phosphate in alkaline calcareous soils). With nano-fertilizers emerging as alternatives to conventional fertilizers, build ups of nutrients in soils and thereby eutrophication and drinking water contamination may be eliminated. In fact, nano-technology has opened up new opportunities to improve nutrient use efficiency and minimize costs of environmental protection. It has helped to divulge to recent findings that plant roots and microorganisms can directly lift nutrient ions from solid phase of minerals (that includes so-called susceptible (i.e., easily weatherable, as well as non-susceptible minerals)

Single DNA conformations and biological function

From a nanoscience perspective, cellular processes and their reduced in vitro imitations provide extraordinary examples for highly robust few or single molecule reaction pathways. A prime example are biochemical reactions involving DNA molecules, and the coupling of these reactions to the physical conformations of DNA. In this review, we summarise recent results on the following phenomena: We investigate the biophysical properties of DNA-looping and the equilibrium configurations of DNA-knots, whose relevance to biological processes are increasingly appreciated. We discuss how random DNA-looping may be related to the efficiency of the target search process of proteins for their specific binding site on the DNA molecule. And we dwell on the spontaneous formation of intermittent DNA nanobubbles and their importance for biological processes, such as transcription initiation. The physical properties of DNA may indeed turn out to be particularly suitable for the use of DNA in nanosensing applications.Comment: 53 pages, 45 figures. Slightly revised version of a review article, that is going to appear in the J. Comput. Theoret. Nanoscience; some typos correcte