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1.
Expert opinion on nanotechnology: risks,benefits, and regulation 总被引:2,自引:2,他引:0
John C. Besley Victoria L. Kramer Susanna H. Priest 《Journal of nanoparticle research》2008,10(4):549-558
A survey of American (US) nanotechnology researchers (N = 177) suggests a diversity of views about what areas are most important to the burgeoning field, as well as perceptions about
the overall benefits and risks of such research. On average, respondents saw a range of technologies as key and viewed public
health and environmental issues as areas where both risks and the need for regulation are greatest. These areas were also
where respondents said current regulations were least adequate. Factor analyses of the survey questions suggest that, when
considering both risks and regulations, respondents make a distinction between health and environmental risks, and what might
be termed “social risks” (e.g., invasion of privacy, use of nanotechnology in weapons, and economic impacts).
相似文献
John C. BesleyEmail: |
2.
The emergence and policy implications of converging new technologies integrated from the nanoscale 总被引:4,自引:4,他引:0
Science based on the unified concepts on matter at the nanoscale provides a new foundation for knowledge creation, innovation, and technology integration. Convergent new technologies refers to the synergistic combination of nanotechnology, biotechnology, information technology and cognitive sciences (NBIC), each of which is currently progressing at a rapid rate, experiencing qualitative advancements, and interacting with the more established fields such as mathematics and environmental technologies (Roco & Bainbridge, 2002). It is expected that converging technologies will bring about tremendous improvements in transforming tools, new products and services, enable human personal abilities and social achievements, and reshape societal relationships.After a brief overview of the general implications of converging new technologies, this paper focuses on its effects on R&D policies and business models as part of changing societal relationships. These R&D policies will have implications on investments in research and industry, with the main goal of taking advantage of the transformative development of NBIC. Introduction of converging technologies must be done with respect of immediate concerns (privacy, toxicity of new materials, etc.) and longer-term concerns including human integrity, dignity and welfare. The efficient introduction and development of converging new technologies will require new organizations and business models, as well as solutions for preparing the economy, such as multifunctional research facilities, integrative technology platforms, and global risk governance.(*) This is an extension of the presentation made at the Converging Technologies Conference, February 26, 2004, New York.This revised version was published online in August 2005 with a corrected issue number. 相似文献
3.
Moh’d Rezeq 《Applied Surface Science》2011,258(5):1750
Nanotips are highly demanded for various applications in nanotechnology. For instance, nanotips with a single atom end can be used as a source of self collimated electron or ion beams. Such tips are usually characterized in the field ion microscope (FIM) or the field emission microscope (FEM), where only a top view can be captured and analyzed. We have noticed that single atom tips fabricated by different methods produce electrons in FEM mode, or ions in FIM mode, at a wide range of applied voltages for the respective mode. In this work we present numerical and analytical analyses to the distribution of the electric field in the vicinity of the nanotip apex that holds the topmost single atom. We demonstrate that although the electric field is relatively enhanced by the nano protrusion it is still significantly dominated by the tip base. The analyses explicitly show that nanotips with broad bases produce even less field than some modest tips, at the same applied voltage. This pronounced effect of the tip base accounts for the relatively high voltages needed at the imaging threshold field. The results reveal that single atom tips are not necessarily sharp at a mesoscopic scale and the tip sharpness has to be determined from the combination of the nanotip apex (FIM or FEM) image and the applied voltage. 相似文献
4.
Igor Linkov Jeffery Steevens Gitanjali Adlakha-Hutcheon Erin Bennett Mark Chappell Vicki Colvin J. Michael Davis Thomas Davis Alison Elder Steffen Foss Hansen Pertti Bert Hakkinen Saber M. Hussain Delara Karkan Rafi Korenstein Iseult Lynch Chris Metcalfe Abou Bakr Ramadan F. Kyle Satterstrom 《Journal of nanoparticle research》2009,11(3):513-527
Nanomaterials and their associated technologies hold promising opportunities for the development of new materials and applications
in a wide variety of disciplines, including medicine, environmental remediation, waste treatment, and energy conservation.
However, current information regarding the environmental effects and health risks associated with nanomaterials is limited
and sometimes contradictory. This article summarizes the conclusions of a 2008 NATO workshop designed to evaluate the wide-scale
implications (e.g., benefits, risks, and costs) of the use of nanomaterials on human health and the environment. A unique
feature of this workshop was its interdisciplinary nature and focus on the practical needs of policy decision makers. Workshop
presentations and discussion panels were structured along four main themes: technology and benefits, human health risk, environmental
risk, and policy implications. Four corresponding working groups (WGs) were formed to develop detailed summaries of the state-of-the-science
in their respective areas and to discuss emerging gaps and research needs. The WGs identified gaps between the rapid advances
in the types and applications of nanomaterials and the slower pace of human health and environmental risk science, along with
strategies to reduce the uncertainties associated with calculating these risks. 相似文献
5.
Carl A. Batt Anna M. Waldron Natalie Broadwater 《Journal of nanoparticle research》2008,10(7):1141-1148
Nanotechnology will be an increasing part of the everyday lives of most people in the world. There is a general recognition
that few people understand the implications of the technology, the technology itself or even the definition of the word. This
lack of understanding stems from a lack of knowledge about science in general but more specifically difficulty in grasping
the size scale and symbolism of nanotechnology. A potential key to informing the general public is establishing the ability
to comprehend the scale of nanotechnology. Transitioning from the macro to the nanoscale seems to require an ability to comprehend
scales of one-billion. Scaling is a skill not common in most individuals and tests of their ability to extrapolate size based
upon scaling a common object demonstrates that most individuals cannot scale to the extent needed to make the transition to
nanoscale. Symbolism is another important vehicle to providing the general public with a basis to understand the concepts
of nanotechnology. With increasing age, individuals are able to draw representations of atomic scale objects, but these tend
to be iconic and the different representations not easily translated. Ball and stick models are most recognized by the public,
which provides an opportunity to present not only useful symbolism but also a reference point for the atomic scale. 相似文献
6.
Characterization of size, surface charge, and agglomeration state of nanoparticle dispersions for toxicological studies 总被引:5,自引:0,他引:5
Characterizing the state of nanoparticles (such as size, surface charge, and degree of agglomeration) in aqueous suspensions
and understanding the parameters that affect this state are imperative for toxicity investigations. In this study, the role
of important factors such as solution ionic strength, pH, and particle surface chemistry that control nanoparticle dispersion
was examined. The size and zeta potential of four TiO2 and three quantum dot samples dispersed in different solutions (including one physiological medium) were characterized. For
15 nm TiO2 dispersions, the increase of ionic strength from 0.001 M to 0.1 M led to a 50-fold increase in the hydrodynamic diameter,
and the variation of pH resulted in significant change of particle surface charge and the hydrodynamic size. It was shown
that both adsorbing multiply charged ions (e.g., pyrophosphate ions) onto the TiO2 nanoparticle surface and coating quantum dot nanocrystals with polymers (e.g., polyethylene glycol) suppressed agglomeration
and stabilized the dispersions. DLVO theory was used to qualitatively understand nanoparticle dispersion stability. A methodology
using different ultrasonication techniques (bath and probe) was developed to distinguish agglomerates from aggregates (strong
bonds), and to estimate the extent of particle agglomeration. Probe ultrasonication performed better than bath ultrasonication
in dispersing TiO2 agglomerates when the stabilizing agent sodium pyrophosphate was used. Commercially available Degussa P25 and in-house synthesized
TiO2 nanoparticles were used to demonstrate identification of aggregated and agglomerated samples. 相似文献
7.
Prashant Mohanpuria Nisha K. Rana Sudesh Kumar Yadav 《Journal of nanoparticle research》2008,10(3):507-517
Nanotechnology involves the production, manipulation and use of materials ranging in size from less than a micron to that
of individual atoms. Although nanomaterials may be synthesized using chemical approaches, it is now possible to include the
use of biological materials. In this review, we critically assess the role of microorganisms and plants in the synthesis of
nanoparticles. 相似文献
8.
J. Ryckebusch W. Cosyn B. Van Overmeire C. Martınez 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):585-587
We present a selection of results obtained within the context of a relativistic eikonal model. First, results of relativistic
Glauber calculations for the nuclear transparency extracted from photon-induced pion production are presented. Second, computed
differential cross-sections for the 12
C(p, 2p) are compared to data. 相似文献
9.
The application of high-frequency acoustic devices to the enhancement of electronics saw an extraordinary growth in both Eastern and Western countries in the sixties and seventies. A major impetus for these developments was the tension existing between the Soviet Bloc countries in the east and the former Allied countries in the west. Government military spending on both sides provided funding to explore new acoustoelectronic concepts in universities, institutes, and major defense companies. The direct exchange of visits between scientists and engineers of the East and West was limited until the 1980s, when travel restrictions were lifted on both sides and authors that has previously only been names in the open literature became face-to-face contacts and enjoyed exchanges at conferences of mutual interest. This resulted in a new era of cooperative work between the East and West and a large number of device applications that are seen in electronic systems around the world today. This paper explores the major acoustoelectronic developments of the sixties and seventies from an eastern and western perspective. 相似文献
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T. Chiarusi S. Cecchini G. Giacomelli S. Manzoor E. Medinaceli L. Patrizii V. Togo 《Radiation measurements》2005,40(2-6):424
CAKE (cosmic abundances below the knee energies) is a prototype balloon experiment for the determination of the charge spectra of the primary cosmic-ray nuclei with Z>28 and the search for exotic heavy particles in the primary cosmic radiation. CAKE is made of stacks of CR39® and Lexan® nuclear track detectors; it has a geometric acceptance of about 1.7 m2 sr for Fe nuclei. Here, the scanning strategy and the algorithms used for tracking in automatic mode of the CR events are presented. 相似文献
13.
A new determination of the potential energy function of the carbon dioxide molecule from its vibrorotational spectrum is presented. Starting from the previous determination made by A. Chédin [J. Mol. Spectrosc.76, 430–491 (1979)] and from a significantly larger set of updated experimental data, the new potential is shown to provide a better agreement between theoretical and experimental eigenenergies. A similar improvement in the prediction of eigenstates is expected. 相似文献
14.
Worldwide nanotechnology development: a comparative study of USPTO,EPO, and JPO patents (1976–2004) 总被引:1,自引:0,他引:1
To assess worldwide development of nanotechnology, this paper compares the numbers and contents of nanotechnology patents
in the United States Patent and Trademark Office (USPTO), European Patent Office (EPO), and Japan Patent Office (JPO). It
uses the patent databases as indicators of nanotechnology trends via bibliographic analysis, content map analysis, and citation
network analysis on nanotechnology patents per country, institution, and technology field. The numbers of nanotechnology patents
published in USPTO and EPO have continued to increase quasi-exponentially since 1980, while those published in JPO stabilized
after 1993. Institutions and individuals located in the same region as a repository’s patent office have a higher contribution
to the nanotechnology patent publication in that repository (“home advantage” effect). The USPTO and EPO databases had similar high-productivity contributing countries and technology fields with large number of
patents, but quite different high-impact countries and technology fields after the average number of received cites. Bibliographic analysis on USPTO and EPO patents shows that researchers in the United States and Japan published larger numbers
of patents than other countries, and that their patents were more frequently cited by other patents. Nanotechnology patents
covered physics research topics in all three repositories. In addition, USPTO showed the broadest representation in coverage
in biomedical and electronics areas. The analysis of citations by technology field indicates that USPTO had a clear pattern
of knowledge diffusion from highly cited fields to less cited fields, while EPO showed knowledge exchange mainly occurred
among highly cited fields. 相似文献
15.
A new particle detector relying on an unusual avalanche mechanism mainly mediated by UV photons permits multistage amplification of ionization electrons. Single electrons are detectable. Particle fluxes, orders of magnitude more intense than in wire chambers, are acceptable. Applications can be foreseen for ?erenkov light imaging, radio-chromatography, slow neutron and X-ray detection. 相似文献
16.
Michael A. Liberman Nathan Kleeorin Igor Rogachevskii Nils Erland L. Haugen 《Combustion Theory and Modelling》2013,17(6):1084-1102
Understanding the causes and mechanisms of large explosions, especially dust explosions, is essential for minimising devastating hazards in many industrial processes. It is known that unconfined dust explosions begin as primary (turbulent) deflagrations followed by a devastating secondary explosion. The secondary explosion may propagate with a speed of up to 1000 m/s producing overpressures of over 8–10 atm, which is comparable with overpressures produced in detonation. Since detonation is the only established theory that allows rapid burning producing a high pressure that can be sustained in open areas, the generally accepted view was that the mechanism explaining the high rate of combustion in dust explosions is deflagration-to-detonation transition. In the present work we propose a theoretical substantiation of an alternative mechanism explaining the origin of the secondary explosion producing high speeds of combustion and high overpressures in unconfined dust explosions. We show that the clustering of dust particles in a turbulent flow ahead of the advancing flame front gives rise to a significant increase of the thermal radiation absorption length. This effect ensures that clusters of dust particles are exposed to and heated by radiation from hot combustion products of dust explosions for a sufficiently long time to become multi-point ignition kernels in a large volume ahead of the advancing flame. The ignition times of a fuel–air mixture caused by radiatively heated clusters of particles is considerably reduced compared with the ignition time caused by an isolated particle. Radiation-induced multipoint ignitions of a large volume of fuel–air ahead of the primary flame efficiently increase the total flame area, giving rise to the secondary explosion, which results in the high rates of combustion and overpressures required to account for the observed level of overpressures and damage in unconfined dust explosions, such as for example the 2005 Buncefield explosion and several vapour cloud explosions of severity similar to that of the Buncefield incident. 相似文献
17.
V. N. Kushnir S. L. Prischepa C. Cirillo C. Attanasio 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,52(1):9-14
The influence of the finite transparency,
, of superconductor/normal metal
(S/N) interface on the critical temperature of proximity coupled layered
structures is investigated in the dirty limit on the basis of the
microscopic equations solved exactly by a matrix method. The calculated
theoretical curves satisfactory reproduce the experimental dependencies of
the critical temperature on the thickness of the superconducting layers in
N/S/N trilayers. The relation between the transparency coefficient and the
normal metal coherence length is also discussed. 相似文献
18.
Bibhas Kumar Dutta 《Physics letters. A》2013,377(31-33):1890-1897
The evolution of nonlinear behaviour of electromagnetically induced absorption and transparency subject to coherent perturbation, is presented in a triply driven five-level atomic system. It has been shown that the coherence effects like absolute line narrowing, single or multiple transparencies, sharply varying dispersion and two opposite types of quantum switching can be efficiently controlled by interference induced among the Rabi-split resonances at various situations. As far as measurement induced subwavelength atom localization is concerned, this model can be very much useful in controlling single peak atom localization in subwavelength and sub-half-wavelength domain by three different ways. 相似文献
19.
Ana Paula de Lima Batista 《Molecular physics》2013,111(24):3085-3094
Electronic states of a new molecular species, SiAs, correlating with the three lowest dissociation channels are characterized at a high-level of theory using the CASSCF/MRCI approach along with quintuple-ξ quality basis sets. This characterization includes potential energy curves, vibrational energy levels, spectroscopic parameters, dipole and transition dipole moment functions, transition probabilities, and radiative lifetimes. For the ground state (X2Π), an assessment of spin–orbit effects and the interaction with the close-lying A2Σ+ state is also reported. Similarities and differences with other isovalent species such as SiP and CAs are also discussed. 相似文献
20.