Light Scattering from Nonequilibrium Concentration Fluctuations in a Polymer solution

We have performed light-scattering measurements in dilute and semidilute polymer solutions of polystyrene in toluene when subjected to stationary temperature gradients. Five solutions with concentrations below and one solution with a concentration above the overlap concentration were investigated. The experiments confirm the presence of long-range nonequilibrium concentration fluctuations which are proportional to $(\nabla T)^2/k^4$, where $\nabla T$ is the applied temperature gradient and $k$ is the wave number of the fluctuations. In addition, we demonstrate that the strength of the nonequilibrium concentration fluctuations, observed in the dilute and semidilute solution regime, agrees with theoretical values calculated from fluctuating hydrodynamics. Further theoretical and experimental work will be needed to understand nonequilibrium fluctuations in polymer solutions at higher concentrations.Comment: revtex, 16 pages, 7 figures. J. Chem. Phys., to appea

Gravity‐induced density and concentration profiles in binary mixtures near gas–liquid critical lines

We have calculated gravity‐induced density and concentration gradients using scaled equations of state fashioned after that of Leung and Griffiths for binary mixtures near gas–liquid critical lines. The mixtures considered here are those of helium‐3 and helium‐4 and of carbon dioxide and ethane. Our calculations show that the density profiles for both mixtures in any proportion of the components are similar to those of pure fluids. The concentration gradients in the helium mixture have the same appearance as the density gradients. In the carbon dioxide–ethane system, however, the form of the concentration profile varies greatly, depending on the overall composition. Moreover, the temperature at which a mixture separates into two phases is slightly different from that expected for the mixture in the absence of gravity. We have also examined the case where a mixture is subjected to a large gravitational field such as can be generated in a centrifuge and found that, although the density gradient in all the mixtures is like that in pure fluids, the concentration gradients in the mixtures of carbon dioxide and ethane have complex features related to the presence of critical azeotropy

Master crossover functions for the one-component fluid "subclass"

Introducing three well-defined dimensionless numbers, we establish the link between the scale dilatation method able to estimate master (i.e. unique) singular behaviors of the one-component fluid "subclass" and the universal crossover functions recently estimated [Garrabos and Bervillier, Phys. Rev. E 74, 021113 (2006)] from the bounded results of the massive renormalization scheme applied to the..

Fluid physics, thermodynamics, and heat transfer experiments in space

An overstudy committee was formed to study and recommend fundamental experiments in fluid physics, thermodynamics, and heat transfer for experimentation in orbit, using the space shuttle system and a space laboratory. The space environment, particularly the low-gravity condition, is an indispensable requirement for all the recommended experiments. The experiments fell broadly into five groups: critical-point thermophysical phenomena, fluid surface dynamics and capillarity, convection at reduced gravity, non-heated multiphase mixtures, and multiphase heat transfer. The Committee attempted to assess the effects of g-jitter and other perturbations of the gravitational field on the conduct of the experiments. A series of ground-based experiments are recommended to define some of the phenomena and to develop reliable instrumentation

Content Validation of a Practice-Based Work Capacity Assessment Instrument Using ICF Core Sets

PURPOSE: A shift from providing long-term disability benefits to promoting work reintegration of people with remaining work capacity in many countries requires new instruments for work capacity assessments. Recently, a practice-based instrument addressing biopsychosocial aspects of functioning, the Social Medical Work Capacity instrument (SMWC), was developed. Our aim was to examine the content validity of the SMWC using ICF core sets. METHODS: First, we conducted a systematic search to identify relevant ICF core sets for the working age population. Second the content of these core sets were mapped to assess the relevance and comprehensiveness of the SMWC. Next, we compared the content of the SMWC with the ICF-core sets. RESULTS: Two work-related core sets and 31 disease-specific core sets were identified. The SMWC and the two work-related core sets overlap on 47 categories. Compared to the work-related core sets, the Body Functions and Activities and Participation are well represented in the new instrument, while the component Environmental factors is under-represented. Compared to the disease-specific core sets, items related to the social and domestic environmental factors are under-represented, while the SMWC included work-related factors complementary to the ICF. CONCLUSION: The SMWC content seems relevant, but could be more comprehensive for the purpose of individual work capacity assessments. To improve assessing relevant biopsychosocial aspects, it is recommended to extend the instrument by adding personal and environmental (work- and social-related) factors as well as a more tailored use of the SMWC for assessing work capacity of persons with specific diseases or underlying illness. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10926-020-09918-7) contains supplementary material, which is available to authorized users

Smart Eco-CityDevelopment in Europe and China: Opportunities, Drivers and Challenges

The policy pointers presented in this report are the result of a three-year (2015-18) research project led by Federico Caprotti at the University of Exeter. The project, Smart Eco-Cities for a Green Economy: A Comparative Analysis of Europe and China, was delivered by a research consortium comprising scholars and researchers in the UK, China, the Netherlands, France, and Germany. The aim of the project was to investigate the way in which smart city and eco-city strategies are used to enable a transition towards digital and green economies. While previous work has considered smart cities and eco-cities as separate urban development models, the project considers them together for the first time. We use the term ‘the smart eco-city’ to focus on how green targets are now included in smart city development policies and strategies. This report presents a summary of policy pointers, or ‘lessons’, learned through our work on the cities we studied in the UK, China, the Netherlands, France and Germany. Specifically, we studied, in depth, the cities of Manchester, Amsterdam, Hamburg, Bordeaux, Shanghai, Shenzhen, Ningbo and Wuhan. This work included interviews with policymakers, urban municipal authorities, tech firm executives, and grassroots and community representatives and stakeholders. Our work also included intensive and in-depth qualitative analysis of documentary sources including policy and corporate reports and other materials.The research undertaken to produce this report was supported by funding from: the Economic and Social Research Council (ESRC) through research grant ES/ L015978/1; the National Natural Science Foundation of China, project number 71461137005; the Netherlands Organisation for Scientific Research (NWO) through research grant 467-14-153 and the Dutch Academy of Sciences (KNAW) through research grant 530-6CD108; the French National Research Agency (ANR) through research grant ANR-14-02; and the German Research Foundation DFG through research grant SP 1545/1-1