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The 14th REHVA HVAC World Congress CLIMA2022 challenges advances in technologies for smart energy transition, digitization, circularity, health and well-being in buildings. How can we create circular buildings, fully heated, cooled and powered by renewable energy? How can we design human-centered indoor environments while mastering life-cycle costs? How can we also include their integration into infrastructure for energy, health, data and education?

The high-flux deuterium plasma impinging on a divertor degrades the long-termthermo-mechanical performance of its tungsten plasma-facing components. A prime actor inthis is hydrogen embrittlement, a degradation phenomenon that involves the interactions between hydrogen and dislocations, the primary carriers of plasticity. Measuring such nanoscaleinteractions is still very challenging, which limits our understanding. Here, we demonstrate anexperimental approach that combines thermal desorption spectroscopy (TDS) andnanoindentation, allowing to investigate the effect of hydrogen on the dislocation mobility in tungsten. Dislocation mobility was found to be reduced after deuterium injection, which ismanifested as a ‘pop-in’ in the indentation stress-strain curve, with an average activation stressfor dislocation mobility that was more than doubled. All experimental results can be confidentlyexplained, in conjunction with experimental and numerical literature findings, by the simultaneous activation of three mechanisms responsible for dislocation pinning: (i) hydrogentrapping at pre-existing dislocations, (ii) hydrogen-induced vacancies, and (iii) stabilization ofvacancies by hydrogen, contributing respectively 38%, 52%, and 34% to the extra activationstress. These mechanisms are considered to be essential for the proper understanding and modeling of hydrogen embrittlement in tungsten.

Transactive based control mechanism (TCM) needs the IoT environment to fully explore flexibility potential from the end-users to offer to involved actors of the smart energy system. On the other hand, many IoT based energy management systems are already available to a market. This paper presents an ap-proach to connect the current demand-driven (top-down) energy management system (EMS) with a market-driven (bottom-up) demand response program. To this end, this paper considers multi-agent system (MAS) to realize the approach and introduces the concept and standardize design of Agilometer. It is described as an elemental agent of the approach. Proposed by authors Agilometer consists of three different functional blocks, which are formulated as an IoT platform according to the LonWorks standard. Moreover, the paper also performs an evaluation study in order to validate the proposed concept and design.

This paper summarizes a study undertaken to reveal potential challenges and opportunities for using building performance simulation (BPS) tools. The paper reviews current trends in building simulation and outlines major criteria for BPS tools selection and evaluation based on analyzing user’s needs for tools capabilities and requirement specifications. The research is carried out by means of a literature review and two online surveys. The findings are based on an inter-group comparison between architects and engineers’. The aim is to rank BPS tools selection criteria and compare ten state-of-the-arts BPS tools in the USA market. Five criteria are composed to stack up against theories and practices of BPS. Based on the experience gained during the survey, suggested criteria are critically reviewed and tested. The final results indicate a wide gap between architects and engineers priorities and tools ranking. This gap is discussed and suggestions for improvement of current tools are presented.

info:eu-repo/semantics/nonPublished

Salt weathering is a major cause of deterioration of porous building materials. Of the salts responsible, especially sodium sulfate is seen as very damaging. However many questions arise concerning which sodium sulfate phase will crystallize out during salt weathering. In this study we focused on the crystallization during isothermal drying of a sample saturated with a sodium sulfate solution. As the material is drying moisture will leave and hence the salt concentration will rise until the maximum solubility is reached. From that point on crystals will be formed. Using NMR we have measured quasi simultaneously both the moisture and Na profiles during drying. These experiments have been performed at various temperatures and concentrations. In our NMR experiments we observe the formation of a metastable phase of sodium sulfate, the heptahydrate crystals.

This paper provides an overview of the use of building performance simulation (BPS) among the building design professionals in Egypt. To assess the situation and highlight the status and difficulties encounter in the usage and the needs for BPS tools, three workshops were held, in July and August 2010 in Cairo. The paper first presents a brief overview of the status of the use of BPS in practice then describes the methods used, including, surveys, interviews, tools testing, brainstorming sessions and discussions. Finally, the study presents recommendations for the process of developing and using performance simulation tools for building design support.

A wide range of scientifically validated Building Performance Simulation tools BPS is available internationally. The users of those tools are mainly researchers, physicists and experts who value empirical validation, analytical verification and calibration of uncertainty as defined by e.g. BESTEST. However, literature and comparative surveys indicate that most architects who use BPS tools in design practice are much more concerned with the (1) Usability and Information Management (UIM) of interface and (2) the Integration of Intelligent design Knowledge-Base (IIKB). Those two issues are the main factors for identifying a building simulation program as “Architect Friendly”. Now, with the advancement of BPS tools and the recent announcements of direct links between BIM or non-BIM modeling tools and BPS tools it is important to compare the existing programs. Based on an online survey, this paper presents the results of comparing ten major BPS tools. The following programs are compared: ECOTECT, HEED, Energy 10, Design Builder, eQUEST, DOE-2, Green Building Studio, IES VE, Energy Plus and Energy Plus-SketchUp Plugin (OpenStudio). With 249 valid responses, the survey ranked the tools in three classes and revealed that architects seek the IIKB above the UIM of the interface. Finally, the paper summarizes the key findings and underlines the major requirements for future improvement and development of BPS tools, mainly from an architectural perspective.

Metastatic prostate cancer continues to be the second leading cause of cancer death in American men with an estimated 28,660 deaths in 2008. Recently, monocyte chemoattractant protein-1 (MCP-1, CCL2) has been identified as an important factor in the regulation of prostate metastasis. CCL2, shown to attract macrophages to the tumor site, has a direct promotional effect on tumor cell proliferation, migration, and survival. Previous studies have shown that anti-CCL2 antibodies given in combination with docetaxel were able to induce tumor regression in a pre-clinical prostate cancer model. A limitation for evaluating new treatments for metastatic prostate cancer to bone is the inability of imaging to objectively assess response to treatment. Diffusion-weighted MRI (DW-MRI) assesses response to anticancer therapies by quantifying the random (i.e., Brownian) motion of water molecules within the tumor mass, thus identifying cells undergoing apoptosis. We sought to measure the treatment response of prostate cancer in an osseous site to docetaxel, an anti-CCL2 agent, and combination treatments using DW-MRI. Measurements of tumor apparent diffusion coefficient (ADC) values were accomplished over time during a 14-day treatment period and compared to response as measured by bioluminescence imaging and survival studies. The diffusion data provided early predictive evidence of the most effective therapy, with survival data results correlating with the DW-MRI findings. DW-MRI is under active investigation in the pre-clinical and clinical settings to provide a sensitive and quantifiable means for early assessment of cancer treatment outcome. J. Cell. Biochem. 107: 58???64, 2009. ?? 2009 Wiley-Liss, Inc.

Chemical recycling of polycarbonate by depolymerization with phenol produces a mixture of phenol, diphenyl carbonate (DPC) and bisphenol A (BPA). We simulate a semibatch extraction process to separate these components. A supercritical carbon dioxide stream flows into an autoclave containing the depolymerization products. The liquid–vapor two-phase system is considered to be in equilibrium during the isobaric isothermal process as the vapor phase is withdrawn sufficiently slowly, maintaining the autoclave temperature and pressure. The VLE behavior is described by the Peng–Robinson equation of state (PR-EOS), using the interaction parameters of the involved six binary systems as determined in our previous work. PR-EOS is coupled with the molar balance equations to calculate the phase fractions and compositions in the investigated systems. The predictions of the simulations are compared with the experimental measurements during extractions from binary systems phenol–CO2 and DPC–CO2 , ternary systems phenol–DPC–CO2 and phenol–BPA–CO2 , agreement between our predictions and experimental results.

Coordination plays a key role in solving decomposed optimal design problems. Several coordination strategies have been proposed in the multidisciplinary optimization (MDO) literature. They are usually presented as a sequence of statements. However, a precise description of the concurrency in the coordination is needed for large multilevel or non-hierarchic coordination architectures. This article proposes the use of communicating sequential processes (CSP) concepts from concurrency theory for specifying and implementing coordination strategies in distributed multilevel optimization rigorously. CSP enables the description of the coordination as a number of parallel processes that operate independently and communicate synchronously. For this purpose, we introduce elements of the language??, a CSP-based language that contains advanced data modeling constructs. The associated software toolkit allows execution of the specified coordination. Coordination specification using?? is demonstrated for analytical target cascading (ATC), a methodology for design optimization of hierarchically decomposed multilevel systems. It is shown that the ATC coordination can be compactly specified for various coordination schemes. This illustrates the advantage of using a high-level concurrent language, such as??, for specifying the coordination of distributed optimal design problems. Moreover, the?? software toolkit is useful in implementing alternative schemes rapidly, thus enabling the comparison of different MDO methods.

Vapor-liquid phase equilibrium is studied for the systems composed of phenol, diphenyl carbonate (DPC), bisphenol A (BPA) and CO2. Bubble point pressures and vapor-phase compositions are measured at various temperatures (343.15-473.15 K) for several compositions of the following systems: two binary systems DPC-CO2 and BPA-CO2, three ternary systems phenol-DPC-CO2, phenol-BPA-CO2 and DPC-BPA-CO2, and one quaternary system phenol-DPC-BPA-CO2. The Peng-Robinson equation of state (PR EOS) binary interaction parameters for the systems DPC-CO2 and BPA-CO2 are optimized by directly fitting to the corresponding experimental data. The PR EOS binary interaction parameters for phenol-DPC, phenol-BPA and DPC-BPA are obtained by fitting to experimental data of the ternary systems involving these constituents and CO2. The binary interaction parameters are then used to predict the phase equilibrium behavior of the quaternary system. A reasonable agreement with the experimental observations of this quaternary system indicates the predictive ability of the model in the range of our experimental measurements.

The formation of asymmetric bis-complexes, based on terpyridine ligands and ruthenium ions, is described as a powerful tool for the self-assembly of polymer blocks end-functionalized with terpyridine units. This is illustrated in this contribution for the synthesis of amphiphilic metallo-supramolecular block copolymers, which are further used to produce aqueous micelles. Finally, the reversibility of the supramolecular bond opens new avenues for the preparation and manipulation of these nano-objects.

Aqueous micelles have been prepared from amphiphilic supramolecular graft copolymers, in which poly(ethylene glycol) (PEG) side chains were linked to a poly(methyl methacrylate) (PMMA) backbone via ruthenium(II)-terpyridine complexes. Three different graft copolymers were investigated, in which the average number of PEG branches (constant length) and the length of the PMMA backbone were varied. The successful formation of micelles was proven by dynamic light scattering (DLS), atomic force microscopy (AFM), and transmission electron microscopy (TEM). A good agreement was found between TEM and AFM observations, which show polydisperse spherical micelles. The hydrodynamic diameter measured by DLS was much larger, suggesting the formation of aggregates. No substantial difference in the micellar characteristic features was found between the three investigated samples.

Two different metallo-supramolecular amphiphilic block copolymers have been synthesized, using a hydrophilic poly(ethylene oxide) block connected through a bis-(2,2':6'2"-terpyridine-ruthenium) complex either to a hydrophobic polystyrene or to a poly(ethylene-co-butylene) block. These copolymers were used to prepare aqueous micelles. The morphological characterization of the metallo-supramolecular micelles was performed by dynamic light scattering and transmission electron microscopy. Besides individual micelles, larger structures were also observed by these two independent techniques. The larger structures were the result of aggregation of individual micelles. In addition, the influence of the ionic strength of the medium was investigated. Although the metallo-supramolecular copolymers do not contain charged blocks, the corresponding micelles behaved as polyelectrolyte-like micelles. This behaviour was attributed to the presence of NaCl ions, strongly associated to the poly(ethylene oxide) blocks. This was evidenced by transmission electron microscopy, that revealed the presence of the salt in the metallo-supramolecular micelles. (C) 2003 Society of Chemical Industry.

An amphiphilic metallo-supramolecular poly(ethylene-co-butylene)-block-poly(ethylene oxide) diblock copolymer containing a bis(2,2′:6′,2″-terpyridine)ruthenium(II) complex as a supramolecular connection between the two constituting blocks was used to prepare stable aqueous micelles. The micelles were characterized by dynamic light scattering and atomic force microscopy. Individual micelles were observed together with aggregates of micelles. Only the addition of a large excess of competitive ligand caused the cleavage of the very stable ruthenium complex. Schematic illustration of PEB70-[Ru]-PEO70 aqueous micelles in water and after the addition of a large excess of competitive ligand.

A metallo-supramolecular ABC triblock copolymer containing a bis(2,2′:6′,2″-terpyridine)-ruthenium(II) complex as a supramolecular connection between the constituting poly(styrene)-block-poly-(2-vinylpyridine) diblock and poly(ethylene oxide) block (PS 32-b-P2VP 13-[Ru]-PEO 70) has been prepared. This copolymer was further utilized in order to prepare aqueous micelles consisting of a PS core, a pH-sensitive P2VP shell, and a PEO corona. The accordingly formed micelles have been characterized by a combination of dynamic light scattering, transmission electron microscopy, and atomic force microscopy. Spherical micelles and a minor fraction of bigger aggregates were observed by these three independent techniques. The pH sensitivity of the P2VP shell could be demonstrated and the reversibility of the metallo-supramolecular complex investigated utilizing a strong competitive ligand.

An amphiphilic metallo-supramolecular polystyrene-block-poly(ethylene oxide) diblock copolymer containing a bis(2,2′:6′,2″-terpyridine)ruthenium(II) complex (PS 20-[Ru]-PEO 70) as a supramolecular connection between the two constituting blocks has been compared to the covalently bonded counterpart (PS 22-b-PEO 70). The two different copolymers have been used to prepare kinetically frozen aqueous micelles that consist of a glassy polystyrene core surrounded by a poly(ethylene oxide) corona. The micelles have been characterized by dynamic light scattering (DLS). In the case of the PS 22-b-PEO 70 copolymer, micelles with a hydrodynamic diameter (D h) of 18 nm are observed while stable micelles with a D h of 65 nm and larger aggregates are formed for the PS 20-[Ru]-PEO 70 sample. Addition of different salts during the initial stage of micelle formation has a deep effect on the final micellar characteristic features, which are now similar to the ones of the covalent system. This effect is attributed to a decreased electrostatic repulsion between the charged bis(2,2′:6′,2″-terpyridine)ruthenium(II) complexes which are present at the interface between the immiscible polystyrene and poly(ethylene oxide) blocks. Furthermore, addition of different salts to solutions of the PS 20-[Ru]-PEO 70 micelles, initially prepared in the absence of salt, caused a decrease of their size, although the packing of the charged bis(2,2′:6′,2″-terpyridine)-ruthenium(II) complexes could not be changed in these kinetically frozen micelles. A decrease in micelle size has also been observed as temperature increases. These effects have not been observed in the covalently connected counterpart and are thought to originate from stretched poly(ethylene oxide) chain segments. A model for metallo-supramolecular micelles is tentatively proposed that takes into account the experimental observations.

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