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[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] Highlights: ► We first describe the role of US/O3 in promoting carbazole degradation in APG1214 solution. ► 20 W ultrasound for 30 min improves the effectiveness of carbazole ozonolysis by 5–10%. ► 40 W or 80 W only plays a role in promoting degradation of carbazole in the first 5 min. ► The content of ·OH radical is inversely proportional to the ultrasound power. ► Absolute value of zeta potential of APG1214 micelles is inversely proportional to US power. - Abstract: We examined the effects of power and treatment time on the ultrasonically enhanced ozonation of carbazole dissolved in APG1214 surfactant solutions, including an analysis of the mechanism of ·OH radical formation, the zeta potential of the colloidal suspension, the influence of ultrasound on micellar morphology, and the degradation kinetics for carbazole and APG1214. A 30 min ultrasound treatment at 28 kHz and 20 W improved the degradation of carbazole by 5–10%, while power levels of 40 W and 80 W provided improvements only during the first 5 min and resulted in reduced degradation after 15 min. The ·OH concentration was inversely proportional to ultrasound power, and directly proportional to the irradiation time. The absolute value of the APG1214 micelle zeta potential was inversely proportional to power and decreased with increasing irradiation time. The relationships of ·OH radical concentration in APG1214 micelles, the zeta potential, and the micellar dynamic radius (Rh) to ultrasonic power and time are the key factors affecting carbazole degradation in this system.
[en] During competitive hybridization the specific and non-specific fractions of tested biomolecules in solution bind jointly with the specific probes immobilized in a separate cell of a microchip. The application of two-compartment model to the two-component hybridization allows analytically investigating the underlying kinetics. It is shown that the behaviour with the non-monotonous growth of complexes formed by the non-specific fraction on a probe cell is a typical feature of competitive hybridization for both diffusion-limited and reaction-limited kinetics. The physical reason behind such an evolution consists in the fact that the characteristic hybridization time for the perfect complexes turns out longer with respect to that for the mismatch complexes. This behaviour should be taken into account for the choice of optimum hybridization and washing conditions for the analysis of specific fraction
[en] This paper presents the effect of spherical aberration on the transverse emittance growth and frequency of oscillation of a beam envelope inside an RF cavity. This paper is organized into two sections. In the first section, the coefficient of spherical aberration which arises due to third order terms of on-axis electric field component is discussed. An expression is derived for the growth of transverse emittance in an RF gap which includes the coupling between the phase spread of the beam and spherical aberration. In the second part, using reduced envelope equation for a laminar beam, effect of aberration on the invariant envelope solution is discussed. An expression is found using the Lindstedt–Poincare theory for solution of the envelope equation. The shift in frequency of oscillation of the beam envelope in the RF field is calculated
[en] There is a continuing need to have reliable physicochemical data for actinide compounds and for the preparation of actinide elements in aqueous solution available for nuclear engineers and scientists. These data are needed for all aspects of the nuclear fuel cycle - from the behaviour of actinides in reactor fuels at high temperature and pressure to actinide behavior in geologic repository environments. This paper summarizes the status of actinide physiochemical data assessment and selection. The topics covered include data assessment of chemical thermodynamic properties and solubilities of actinide compounds and solution equilibria of the actinides. (orig.)
[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] Starting from BPS solutions to Yang-Mills which define a stable holomorphic vector bundle, we investigate its deformations. Assuming slowly varying fieldstrengths, we find in the abelian case a unique deformation given by the abelian Born-Infeld action. We obtain the deformed Donaldson-Uhlenbeck-Yau stability condition to all orders in α'. This result provides strong evidence supporting the claim that the only supersymmetric deformation of the abelian d=10 supersymmetric Yang-Mills action is the Born-Infeld action
[en] Highlights: • The present smart pipet tip enables in situ evaluation of solution characteristics. • Firstly, the electrical charges inside the pipet tip is advantageously utilized. • Multi-parametric effect on liquid-solid triboelectricity is effectively separated. • The morphology of nanoparticles can be in situ predicted by using the smart pipet tip. Pipet tips are commonly utilized laboratory tools to transfer adjustable volume of liquid in various fields of chemistry, biology and physics. Recently, we have reported that the ordinary pipetting procedure always involves spontaneous liquid-solid contact electrification, resulting in generation of net electrical charges on the dispensed solution and the inner surface of the polymeric pipet tip. In this study, a concept of a smart pipet tip is proposed to evaluate the electrolyte concentration of the dispensed solution by use of spontaneously generated electric signals during the ordinary pipetting procedure. The smart pipet tip possessing triboelectricity and thermoelectricity detecting modules is advantageous as it performs in situ evaluation of solution characteristics without any subsidiary solution handling process. The spontaneously generated electric signals are intensively investigated with the theoretical analyses. The proof-of-concept demonstration of the present smart pipet tip is shown for in situ prediction of morphology of nanoparticles during their synthetic reaction, which critically determines their catalytic activity.
[en] Highlights: • Refinement of primary Al3Fe phase liquidly quenched from different temperature melt was estimated quantitatively. • Fe solution in primary phases, eutectic microstructures and Al matrix were carried out. • Increased thermoelectric power of melt reveals the destruction of Al-Fe clusters caused by TEMF.
[en] With the recent advances in nanoscale science and engineering, materials containing reinforcement with superior mechanical properties can be found in many advanced products. The accurate prediction of the mechanical properties of this class of composite materials is important to ensure the reliability of the products. Characterization methods based contact probe such as nano-indentation and scratch tests have been developed in recent years to measure the mechanical properties of the new class of nanomaterials. This paper presents a constitutive modeling framework for predicting the mechanical properties of nanoparticle reinforced composite materials. The formulation directly considers the effects of inter-nanoparticle interaction and performs a statistical averaging to the solution of the problem of two-nanoparticle interaction. Final constitutive equations are obtained in analytical closed form with no additional material parameters. The predictions from the proposed constitutive model are compared with experimental measurement from nano-indentation tests. This constitutive model for nanoparticle reinforced composites can be used to determine the volume concentration of the reinforcing nanoparticles in nano-indentation test