Making the use of scenarios in LCA easier: the superstructure approach

Purpose Much progress has recently been made in modelling future background systems for LCA by including future scenario data, e.g. from Integrated Assessment Models (IAMs), into life cycle inventory (LCI) databases. A key problem is, however, that this yields potentially dozens of scenario LCI databases (i.e. LCI databases that represent different scenarios and reference years), instead of a single background database, which is very impractical for LCA modelling purposes. This paper proposes an approach to overcome this problem. Methods The approach consists of transforming all scenario LCI databases into a single superstructure database and an associated scenario difference file. The superstructure database is also a regular LCI database, but is constructed to contain all unique exchanges (elementary and intermediate flows) and processes that exist across all scenario LCI databases. The scenario difference file stores the differences between all scenarios and can be used to turn the superstructure into a specific scenario LCI database. This is very fast as it can be done in memory during LCA calculations. Results and discussion A key advantage of the superstructure approach is that a single LCI database can be used to represent different background systems. Therefore, the practitioner does not need to re-link a foreground system to multiple LCI databases, which is work-intensive and invites modelling errors. LCA results for all scenarios and reference years can be calculated automatically. We also illustrate how the superstructure approach has been implemented in the Activity Browser open source LCA software. Although this paper introduces the superstructure approach for background scenarios, it can also be used to model foreground scenarios, and even, as implemented in the Activity Browser, combinations of background and foreground scenarios. Finally, we briefly discuss further challenges that need to be addressed for a more widespread use of background scenarios in LCA. Conclusions The superstructure approach presents a practical solution for making the use of future background scenarios more wide-spread and, therefore, to overcome the problem of performing prospective LCA with temporally inconsistent foreground and background systems. The implementation in the Activity Browser makes the approach available for anyone and may serve as inspiration for other LCA software to implement the superstructure approach or a similar concept. While this may be an important technical milestone, additional coordination between data providers, scenario generators, LCA practitioners, and software developers will be required to further facilitate the use of background scenarios in prospective LCA studies.

Desarrollo de las capacidades coordinativas en niños: efectos de entrenamiento en el patinaje (Development of coordination skills in children: effects of rollerblading training)

El objetivo del estudio fue determinar el efecto de un programa de aprendizaje de las capacidades coordinativas sobre el tiempo en la prueba de patinaje de 300 metros contra reloj individual y la coordinación general. Participaron 14 niños y niñas entre los seis y ocho años de edad que fueron asignados aleatoriamente al grupo experimental (n=7) o grupo control (n=7); la media de la edad del grupo experimental fue 8,1 años (DE=0.5) y la media del grupo control 7,6 años (DE=0.82); con una experiencia deportiva igual para ambos grupos (16 meses). El grupo experimental tuvo un entrenamiento adicional de coordinación antes de la sesión cotidiana durante 20 sesiones distibuidas en siete semanas. El programa constó de 15 ejercicios en escalerilla realizados en cada sesión asi: tres ejercicios con dos series de 10 repeticiones y recuperación de 30 segundos en la primera serie y dos minutos después de la segunda. El grupo control no recibió estímulo adicional y continuó con el entrenamiento cotidiano del patinaje. Se realizó pre y post-test donde se midió la velocidad con la prueba de 300 m contra reloj individual en patines y la coordinación de los niños con el test Korperkoordination Test fur Kinder. Los resultados mostraron que existen diferencias significativas en las comparaciones intra-grupo, sin embargo, al realizar la comparación inter-grupos, se constató que no existen diferencias significativas (p= 0.180) en velocidad, pero en la práctica del patinaje estas diferencias son relevantes porque determinan una disminución en el tiempo de una prueba contra reloj, que puede significar un cambió ecológico significativo.Abstract. The research objective was to determine the effect of a learning program for coordination skills on the time of the 300-meter rollerblading test against individual clock and on general coordination. A sample of 14 boys and girls between six and eight years old, who were randomly assigned to experimental group (n=7) or control group (n=7) participated in the study; average age of the experimental group was 8,1 years old (SD=0,5), whereas in the control group it was 7,6 years old (SD=0.82); participants from both groups had similar sports experience (16 months). During 20 sessions over seven weeks, the experimental group received additional coordination training before each daily session. The program consisted of 15 ladder exercises, where in each session three exercises were performed with two sets of 10 repetitions and recovery of 30 seconds in the first series and two minutes after the second. The control group did not receive additional stimulus and continued with daily rollerblading training. Pre- and post-test were performed, with speed being measured during the 300m test against individual clock, whilst children's coordination was assessed with the Korperkoordination Test fur Kinder Test. The results showed significant differences in intra-group comparisons; however, when performing the inter-group comparison, no significant differences (p = 0.180) were found in speed. Nonetheless, in rollerblading practice these differences are relevant, because they determine a decrease in the time of a test against the clock, which may mean a significant ecological change.

Argentophilic Interactions in Two AgI Complexes of 3-(2-(Pyridin-4-yl)ethyl)pentane-2,4-dione, a Promising Ditopic Ligand

Reactions of 3-(2-(pyridin-4-yl)ethyl)pentane-2,4-dione (HacacPyen) with AgPF6 and AgBF4 afforded cationic silver complexes [Ag(HacacPyen)2]+ with essentially linear coordination of the Ag I cation by two pyridine N atoms. Rather unexpectedly, the HacacPyen ligands in the PF6- salt 1 adopt the diketo form, in contrast to the uncoordinated HacacPyen molecule, whereas the corresponding BF4- salt 2 and the majority of 3-substituted acetylacetones crystallizes as the enol tautomer. In both compounds 1 and 2, complex cations aggregate via short Ag...Ag interactions to pairs. These contacts amount to 3 . 21 Å in 1 and 3 . 26 Å or 3 . 31 Å in 2. As they are unsupported by any additional bridging ligands and correspond to the closest interionic interactions between neighbouring complex cations, they may be addressed as argentophilic interactions. The PF6- anions in 1 and the BF4- counter ions in 2 are involved in long and presumably electrostatic Ag...F contacts of ca. 2 . 9 Å. Additional coordination between Ag I and keto O atoms of symmetry-equivalent ligands occurs in 1 and leads to an extended two-periodic supramolecular structure.

Examining the role of funders in ensuring value and reducing waste in research: An organizational case-study of the Patient-Centered Outcomes Research Institute

International experts have recommended actions that funders can take to improve the value of research investments. They state that self-assessment and public sharing are the basis for accountability and improvement. We examined our policies and practice to determine the extent to which the Patient-Centered Outcomes Research Institute’s (PCORI) policies and practices as a research funder align with international best practice recommendations. A self-audit of current policies and practice against 17 recommendations and 35 sub-recommendations representing five major stages of research production, based on adapted methods used for self-assessment by another funder, was performed. Fit of existing PCORI policies and practices with 35 sub-recommendations, qualitative assessment of adequacy (area of strength; area of partial strength; area of growth; not applicable) for 17 recommendations for five stages of research production was assessed. Of the 17 recommendations, 15 were applicable to PCORI’s research mission and focus. PCORI has policies and practices in place for all elements of six recommendations (“area of strength”) and policies that address each element but with some still in active development for three (“area of partial strength”). PCORI is partially addressing six of the 15 relevant recommendations (“area of growth”). Areas for growth include making study protocols publicly available, improving policies on data sharing, and enhancing collaboration with other funders to reduce redundant funding. A voluntary consortium of international funders is underway to encourage further progress, including additional self-assessment and public sharing for accountability. These findings indicate PCORI has undertaken efforts to align its funding practices with international recommendations to ensure the value of public dollars invested in research. Further efforts will likely require additional coordination and collaboration between funders and stakeholders.

Studies of the Catalytic Activity of Iron (III) Porphyrins for the Protection of Carbonyl Groups in Homogeneous Media

The protection of carbonyl groups that produce acetal products is a key reaction in fine chemistry due to the high reactivity of aldehydes and ketones in certain media. This process can be catalyzed by protic or Lewis acids. Since metalloporphyrins often possess free axial positions in the central metal, they can be applied as Lewis acid catalysts, allowing the additional coordination of substrates. Therefore, three ferric complexes were selected to be evaluated as catalysts for the acetalization of benzaldehyde with ethanol and triethyl orthoformate (TEOF) in the homogeneous phase: (i) 5,10,15,20-tetrakis(phenylporphyrin) iron (III) chloride (Fe0F); (ii) 5,10,15,20-tetrakis(2,6-difluorphenylporphyrin) iron (III) chloride (Fe2F); and (iii) 5,10,15,20-tetrakis(pentafluorphenylporphyrin) iron (III) chloride (Fe5F). The complex Fe5F showed the highest catalytic activity, and kinetic parameters were evaluated for this reaction, exhibiting an increasing rate of reaction of about 550-fold in comparison with the non-catalyzed reaction. The reaction scope was also investigated, and Fe5F was found to be active for the acetalization of benzaldehyde and acetophenone, with different protective agents such as alcohols, glycols, glycerol, and epoxide being selective for the formation of cyclic acetals. The protection of benzaldehyde with ethylene glycol and propylene glycol were also studied at different temperatures, and turnover frequency (TOF) values of up to 360 h−1 were determined at 40 °C in homogenous media without the need for solvent or drying agents.

Examining the role of funders in ensuring value and reducing waste in research: An organizational case-study of the Patient-Centered Outcomes Research Institute

International experts have recommended actions that funders can take to improve the value of research investments. They state that self-assessment and public sharing are the basis for accountability and improvement. We examined our policies and practice to determine the extent to which the Patient-Centered Outcomes Research Institute’s (PCORI) policies and practices as a research funder align with international best practice recommendations. A self-audit of current policies and practice against 17 recommendations and 35 sub-recommendations representing five major stages of research production, based on adapted methods used for self-assessment by another funder, was performed. Fit of existing PCORI policies and practices with 35 sub-recommendations, qualitative assessment of adequacy (area of strength; area of partial strength; area of growth; not applicable) for 17 recommendations for five stages of research production was assessed. Of the 17 recommendations, 15 were applicable to PCORI’s research mission and focus. PCORI has policies and practices in place for all elements of six recommendations (“area of strength”) and policies that address each element but with some still in active development for three (“area of partial strength”). PCORI is partially addressing six of the 15 relevant recommendations (“area of growth”). Areas for growth include making study protocols publicly available, improving policies on data sharing, and enhancing collaboration with other funders to reduce redundant funding. A voluntary consortium of international funders is underway to encourage further progress, including additional self-assessment and public sharing for accountability. These findings indicate PCORI has undertaken efforts to align its funding practices with international recommendations to ensure the value of public dollars invested in research. Further efforts will likely require additional coordination and collaboration between funders and stakeholders.

Performance of enhanced DuBois type water reduction catalysts (WRC) in artificial photosynthesis – effects of various proton relays during catalysis

A pincer type ligand provides an additional coordination site or a proton relay depending on the metal oxidation state.

IR/Raman characterization of Au-mercaptotriazole crystals

The aim of this study was a characterization of the crystals of gold complexes based on mercaptotrazole, obtained from solutions with different pH values (2, 4, 7, and 9), using the methods of infrared (IR) and Raman spectroscopy. Both methods provided very useful information on the investigated systems and signalized existence of the Au-S bond in the complexes obtained at pH = 2 and 9. Recorded spectra clearly illustrated the changes that occur in the systems as a consequence of pH change. At the same time, the results also showed that the pyrrole nitrogen atoms stay protonated at pH = 9, which is not in favor of the assumption evolved from the previous UV-vis analysis of possible additional coordination between Au and possible deprotonated nitrogen atoms at this particular pH. Keywords: synthesis; gold-mercaptotriazole (Au-MT); IR and Raman spectroscopy

NEW SORBENTS ON LIGNIN BASE FOR WASTE WATER CLINGING FROM HEAVY METALS COMPOUNDS

With using lignin, and vinylidene chloride a new sulfur-containing sorption material was obtained. A distinctive feature of the sorbent is the presence of carbon-carbon double bonds in its structure, which act as -donors for additional coordination of metal ions on the sorbent, thus facilitating their deposi-tion on the surface of the sorbent.

Kinetic Control of Interpenetration in Fe-Biphenyl-4,4′-dicarboxylate MOFs by Coordination and Oxidation Modulation

Phase control in the self-assembly of metal-organic frameworks (MOFs) – materials wherein organic ligands connect metal ions or clusters into network solids with potential porosity – is often a case of trial and error. Judicious control over a number of synthetic variables is required to select for the desired topology and control features such as interpenetration and defectivity, which have significant impact on physical properties and application. Herein, we present a comprehensive investigation of self-assembly in the Fe-biphenyl-4,4'-dicarboxylate system, demonstrating that coordination modulation, the addition of competing ligands into solvothermal syntheses, can reliably tune between the kinetic product, non-interpenetrated MIL-88D(Fe), and the thermodynamic product, two-fold interpenetrated MIL-126(Fe). DFT simulations reveal that correlated disorder of the terminal anions on the metal clusters in the interpentrated phase results in H-bonding between adjacent nets and is the thermodynamic driving force for its formation. Coordination modulation slows self-assembly and therefore selects the thermodynamic product MIL-126(Fe), while offering fine control over defectivity, inducing mesoporosity, but electron microscopy shows the MIL-88D(Fe) phase persists in many samples despite not being evident in diffraction experiments, suggesting its presence accounts for the lower than predicted surface areas reported for samples to date. Interpenetration control is also demonstrated by utilizing the 2,2'-bipyridine-5,5'-dicarboxylate linker; DFT simulations show that it is energetically prohibitive for it to adopt the twisted conformation required to form the interpenetrated phase, and are confirmed by experimental data, although multiple alternative phases are identified due to additional coordination of the Fe cations to the N-donors of the ligand. Finally, we introduce oxidation modulation – the concept of using metal precursors in a different oxidation state to that found in the final MOF – as a further protocol to kinetically control self-assembly. Combining coordination and oxidation modulation allows the synthesis of pristine MIL-126(Fe) with BET surface areas close to the predicted maximum capacity for the first time, suggesting that combining the two may be a powerful methodology for the controlled self-assembly of high-valent MOFs.<br><br>