Results 1 - 10 of 2067
Results 1 - 10 of 2067. Search took: 0.023 seconds
|Sort by: date | relevance|
[en] Ethical and societal issues concerning justice, safety, risks, and benefits are well-established topics in the discourses of nanotechnology innovation and development. That nanotechnology innovation should be socially and ethically responsible is generally accepted by scientists, policymakers, regulators, and industry, and the idea of public involvement and communication is part and parcel of the conceptualization of responsible technology development. This paper systematically reviews the social science research literature accumulated between 2002 and 2018 on the communication of nanotechnology. A critical and constructivist perspective on policy problems guides the analysis. Two questions are asked of this literature: what problems are identified regarding the communication of nanotechnology to the public? How can these problems be managed and/or resolved? Three different problem themes are identified: the public, societal institutions, and nanotechnology itself. While for some identified problems, there are corresponding solutions; in other instances, there is little alignment between problems and solutions. In conclusion, the paper recommends that in communicating nanotechnology to the public: (i) the objectives of communication should be defined; (ii) previous research should be used responsibly; (iii) communication strategies should be adapted to the context; and (iv) effort should not be spent trying to develop a generic framework for communication.
[en] Due to technical constraints this article was published in volume 240:1 with erroneous article citation ID number 1 whereas this should have been 71 which is corrected as such. Springer Nature sincerely apologizes towards the author(s) for the inconvenience caused.
[en] Samples of (TIGaSe2)1-x(TIInSe2)x solid solutions are synthesized. The frequency dependences (2*10''1-10''6 Hz) of components of the total complex impedance are studied by the impedance spectroscopy technique and relaxation processes are investigated depending on the composition of the (TIGaSe2)1-x(TIInSe2)x solid solution in the solubility region (x=0-0.3). Corresponding diagrams on the (Z-Z') complex plane are analyzed using the equivalent substitution circuit method. An anomaly in the temperature dependence of the electrical conductivity, which manifests itself in an abrupt increase in the conductivity, is found for the studied (TIGaSe2)1-x (TIInSe2)x solid solution at 300K. This peculiarity is associated with the phase transition into the superionic state after 0.25 MGy gamma irradiation.
[en] In this study, trisodium citrate was used as draw solute in forward osmosis (FO) due to its biodegradability and easy reuse after FO dilution. The effect of operating conditions on FO performance was investigated. The study focused on the long-term flux performance and membrane fouling when surface water was used as feed solution. A water flux of 9.8 LMH was observed using 0.5 M trisodium citrate as draw solution in PRO mode. In the long-term FO process, trisodium citrate showed a slight decrease in total flux loss (13.06%) after 20 h of operation. The membrane fouling was significantly reduced after a two-step physical cleaning. A considerable flux recovery (> 95%) of the fouled membrane was finally obtained. Therefore, this study proves the superiority of trisodium citrate as draw solution and paves a new way in applying FO directly for surface water reclamation.
[en] A numerically efficient force distribution method for actuator saturation avoidance is proposed, which is applicable to two different types of the mechanisms with two degrees of actuator redundancy, parallel mechanism (PM) and cable-driven parallel mechanism (CDPM). The proposed method searches the optimal force solutions based on their geometric interpretation. Each actuator force with two degrees of actuator redundancy is expressed as a plane equation with respect to two intermediate variables. Thus, the optimal forces are found by searching for both the intersections between force planes and the common intersection points among those force planes. The proposed method for each of PM and CDPM is described. Then for two different exemplary mechanisms, the 2T 2R -type 4- DOF CDPM with six actuation cables and for the 2T1R -type planar 3- DOF PM with five active joints, comparative simulations moving along the spiral trajectory are conducted, employing three different methods, the proposed method and the other two typical off-line methods, the interior point method and the linear matrix inequality method. It is confirmed from those simulation results that the computational efficiency of the proposed method in finding their desired optimal force solutions is superior to the ones of the other two typical offline optimal searching methods and also sufficiently fast enough in real time applications.
[en] Using the impedance spectroscopy methods the charge transfer in solid solution (TlGaSe2)1-x(TlInS2)x in the frequency range of 20-10''6 Hz before and after γ-irradiation with a dose of 0.25 MGy have been investigated. The relaxation character of dielectric constant dispersion and dielectric loss nature are established. The frequency dependence of the dielectric loss tangent (tgδ) in solid solution crystals (TlGaSe2)1-x(TlInS2)x is due not by only the relaxation polarization, but also by through conduction. The response rate is fp=10''3 Hs and the duration of the relaxation period is τ=10''-3s. It is found that the regularity σ∼ f''S (0,1 ≤S≤1,0) indicating on electric conduction on localized states takes place in frequency range 10''5 - 5·10''5 Hz for the electric conduction. The further frequency increase leads to the increase of ionic conductivity and to the system transition in the superionic state.
[en] Using models of thermoassociated polymers, a cellular model of associated solutions is developed for cases where molecules of a solute are able to form from 2 to 6 bonds with each other. It is shown that solutions associated by weak intermolecular interactions in a certain range of concentrations can be considered as systems of flickering pseudo-polymeric macromolecules with a fractal structure.
[en] Statistical processing of the data for multicomponent aqueous systems with a molecular character of the solutions confirms the planarity of the compositions of saturated solutions, expressed in wt % on the lines of monovariant equilibria and in nonvariant points for systems with all types of solutions (ionic, ionic–molecular, and molecular), proving the colligative property of solutions saturated by two or more solid phases.
[en] Nanotechnology provides innovative and promising solutions for the conservation of cultural heritage, but the development and application of new nano-enabled products pose concerns regarding their human health and environmental risks. To address these issues, we propose a sustainability framework implementing the Safe by Design concept to support product developers in the early steps of product development, with the aim to provide safer nano-formulations for conservation, while retaining their functionality. In addition, this framework can support the assessment of sustainability of new products and their comparison to their conventional chemical counterparts if any. The goal is to promote the selection and use of safer and more sustainable nano-based products in different conservation contexts. The application of the proposed framework is illustrated through a hypothetical case which provides a realistic example of the methodological steps to be followed, tailored and iterated along the decision-making process.
[en] The kinematic shear viscosity of aqueous electrolyte solutions has been studied. The temperature dependence of this parameter is shown to be described by an exponential formula at T < Td and a formula of the argon-like type at T > Td , where Td is the temperature of the dipole ordering, in the whole considered concentration interval. Main attention is focused on the peculiarities in the temperature and concentration dependences of the shear viscosity in the argon-like interval. It is shown that the root-like concentration dependence can appear, only if the Debye theory of dilute electrolyte solutions is applicable. Beyond its validity domain, the series expansion of the kinematic shear viscosity in the concentration parameter should have an analytical character. The latter behavior is inherent in the concentration dependence of the shear viscosity in the majority of experiments. The error of reproducing the experimental data did not exceed the experimental one, i.e. it was smaller than 4-5%