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Polymer systems displaying CO2-triggered rheology alteration are widely investigated in recent years, which can change from nonviscous liquid to high-viscosity solution or even gel by passing CO2 through. Among those polymer systems, a previous study of the group shows that a rationally designed ABA-type triblock copolymer with a hydrophilic middle block and two CO2-responsive end blocks can undergo either gel-sol or sol-gel transition triggered by CO2 as a result of increase or decrease in lower critical solution temperature of A blocks, respectively. This paper describes a new and more flexible approach to achieving CO2-induced gelation of polymer aqueous solution at much lower polymer concentrations. It consists in mixing two water-soluble ABA triblock copolymers that have the same B block but different A blocks: for one polymer, the A blocks are a negatively charged polyelectrolyte, and for the other polymer, the A blocks can be turned positively charged under CO2 stimulation. In this way, CO2 bubbling through an aqueous solution of the two constituent triblock copolymers can induce complexation of the oppositely charged A blocks and, as a result, gelation of the solution of mixed triblock copolymers. [ABSTRACT FROM AUTHOR]

In April 2011, we published the first peer-reviewed analysis of the greenhouse gas footprint ( GHG) of shale gas, concluding that the climate impact of shale gas may be worse than that of other fossil fuels such as coal and oil because of methane emissions. We noted the poor quality of publicly available data to support our analysis and called for further research. Our paper spurred a large increase in research and analysis, including several new studies that have better measured methane emissions from natural gas systems. Here, I review this new research in the context of our 2011 paper and the fifth assessment from the Intergovernmental Panel on Climate Change released in 2013. The best data available now indicate that our estimates of methane emission from both shale gas and conventional natural gas were relatively robust. Using these new, best available data and a 20-year time period for comparing the warming potential of methane to carbon dioxide, the conclusion stands that both shale gas and conventional natural gas have a larger GHG than do coal or oil, for any possible use of natural gas and particularly for the primary uses of residential and commercial heating. The 20-year time period is appropriate because of the urgent need to reduce methane emissions over the coming 15-35 years. [ABSTRACT FROM AUTHOR]

The area of dedicated energy crops is expected to increase in Sweden. This will result in direct land use changes, which may affect the carbon stocks in soil and biomass, as well as yield levels and the use of inputs. Carbon dioxide ( CO2) fluxes of biomass are often not considered when calculating the climate impact in life cycle assessments ( LCA) assuming that the CO2 released at combustion has recently been captured by the biomass in question. With the extended time lag between capture and release of CO2 inherent in many perennial bioenergy systems, the relation between carbon neutrality and climate neutrality may be questioned. In this paper, previously published methodologies and models are combined in a methodological framework that can assist LCA practitioners in interpreting the time-dependent climate impact of a bioenergy system. The treatment of carbon differs from conventional LCA practice in that no distinction is made between fossil and biogenic carbon. A time-dependent indicator is used to enable a representation of the climate impact that is not dependent on the choice of a specific characterization time horizon or time of evaluation and that does not use characterization factors, such as global warming potential and global temperature potential. The indicator used to aid in the interpretation phase of this paper is global mean surface temperature change (Δ Ts( n)). A theoretical system producing willow for district heating was used to study land use change effects depending on previous land use and variations in the standing biomass carbon stocks. When replacing annual crops with willow this system presented a cooling contribution to Δ Ts( n). However, the first years after establishing the willow plantation it presented a warming contribution to Δ Ts( n). This behavior was due mainly to soil organic carbon ( SOC) variation. A rapid initial increase in standing biomass counteracted the initial SOC loss. [ABSTRACT FROM AUTHOR]

This paper extends the analysis of our proposed modification to the first model of Libyan Exploration and Production Sharing Agreement ( LEPSA I) to field applications. Four decision-making models are coded in a spreadsheet program to estimate profitability indicators for two development scenarios. These scenarios are primary and secondary recovery methods with water injection and enhanced oil recovery by injecting carbon dioxide. The paper concludes that the economic profit for the foreign investor (second party) under LEPSA I was improved compared with EPSA IV. Also, Libya increased its oil reserves with a reasonable decrease of its production share. Moreover, the results showed that the profit indicators under the current production shares (cost recovery) of the fourth model of Exploration and Production Sharing Agreement ( EPSA IV) were not favourable to the second party. Because of that, the second party would not be motivated to make a decision to invest any money for an oil development projects in Libya. Finally, the paper investigates how EPSA IV should be redesigned to maximise the Libyan National Oil Corporation (first party) oil reserves and give more attention to the economic objectives of the second party. [ABSTRACT FROM AUTHOR]

There is increasing demand for superhydrophobic materials, which can be used for separating oil and water efficiently. To avoid secondary pollution, it is desirable to prepare such materials with green technology. Here, we present an environmentally benign method for fabricating superhydrophobic materials by using organic base based solvents in which cellulose can be dissolved and activated. The dissolved cellulose could be chemically modified with a silanization reagent, and the solvent could be recycled after CO2 was removed. The obtained cellulose nanocoating exhibited excellent hydrophobic effects. By spraying it on filter paper (water contact angle (WCA)=165°) for oil and water separation, the separation efficiency of more than 95 % was achieved; ultrasonication of an ordinary sponge in its dispersion (WCA=163°), meant it could be used as an oil absorber. It can also absorb a certain amount of bisphenol A (BPA), with the concentration decreasing by 66 % from the original concentration (0.1 m m). Besides the high separation efficiency, it is resistant to a wide range of pH solutions, which means that it could be used in harsh environments. More importantly, the process is cost-effective, the solvent can be recycled, and the whole process is green. Thus, the activation method provides a green route for the preparation of other cellulose-based materials. [ABSTRACT FROM AUTHOR]

Biochar application to soils may increase carbon (C) sequestration due to the inputs of recalcitrant organic C. However, the effects of biochar application on the soil greenhouse gas ( GHG) fluxes appear variable among many case studies; therefore, the efficacy of biochar as a carbon sequestration agent for climate change mitigation remains uncertain. We performed a meta-analysis of 91 published papers with 552 paired comparisons to obtain a central tendency of three main GHG fluxes (i.e., CO2, CH4, and N2O) in response to biochar application. Our results showed that biochar application significantly increased soil CO2 fluxes by 22.14%, but decreased N2O fluxes by 30.92% and did not affect CH4 fluxes. As a consequence, biochar application may significantly contribute to an increased global warming potential ( GWP) of total soil GHG fluxes due to the large stimulation of CO2 fluxes. However, soil CO2 fluxes were suppressed when biochar was added to fertilized soils, indicating that biochar application is unlikely to stimulate CO2 fluxes in the agriculture sector, in which N fertilizer inputs are common. Responses of soil GHG fluxes mainly varied with biochar feedstock source and soil texture and the pyrolysis temperature of biochar. Soil and biochar pH, biochar applied rate, and latitude also influence soil GHG fluxes, but to a more limited extent. Our findings provide a scientific basis for developing more rational strategies toward widespread adoption of biochar as a soil amendment for climate change mitigation. [ABSTRACT FROM AUTHOR]

This paper gives an overview of our plasma chemistry modeling for CO2 and CH4 conversion in a dielectric barrier discharge (DBD) and microwave (MW) plasma. We focus on pure CO2 splitting and pure CH4 reforming, as well as mixtures of CO2/CH4, CH4/O2, and CO2/H2O. We show calculation results for the conversion, energy efficiency, and product formation, in comparison with experiments where possible. We also present the underlying chemical reaction pathways, to explain the observed trends. For pure CO2, a comparison is made between a DBD and MW plasma, illustrating that the higher energy efficiency of the latter is attributed to the more important role of the vibrational levels. [ABSTRACT FROM AUTHOR]

In this paper, immersion experiments were carried out to compare corrosion behaviors of low-alloy steel exposed to both H2S/CO2 environments in terms of corrosion kinetics, corrosion products, macroscopic/microscopic surface morphology, cross-section morphology, and elemental distribution. The experimental results demonstrated that the corrosion kinetics of both the corrosion environments was similar. The distinctive corrosion environment accelerated the formation of different corrosion products. The corrosion products of vapor-saturated H2S/CO2 environment were mackinawite, cubic iron sulfide, and greigite, while, the ones of H2S/CO2-saturated brine environment were mackinawite and cubic iron sulfide. The surface formation process was also similar. The vapor-saturated H2S/CO2 environment promoted the formation of fine crystals compared with H2S/CO2-saturated brine environment. Molybdenum accumulated in the inner layer in both the corrosion environments. Two schematic models of corrosion process are proposed based on the experimental data. [ABSTRACT FROM AUTHOR]

Abstract: Biochar application to soils may increase carbon (C) sequestration due to the inputs of recalcitrant organic C. However, the effects of biochar application on the soil greenhouse gas (GHG) fluxes appear variable among many case studies; therefore, the efficacy of biochar as a carbon sequestration agent for climate change mitigation remains uncertain. We performed a meta‐analysis of 91 published papers with 552 paired comparisons to obtain a central tendency of three main GHG fluxes (i.e., CO2, CH4, and N2O) in response to biochar application. Our results showed that biochar application significantly increased soil CO2 fluxes by 22.14%, but decreased N2O fluxes by 30.92% and did not affect CH4 fluxes. As a consequence, biochar application may significantly contribute to an increased global warming potential (GWP) of total soil GHG fluxes due to the large stimulation of CO2 fluxes. However, soil CO2 fluxes were suppressed when biochar was added to fertilized soils, indicating that biochar application is unlikely to stimulate CO2 fluxes in the agriculture sector, in which N fertilizer inputs are common. Responses of soil GHG fluxes mainly varied with biochar feedstock source and soil texture and the pyrolysis temperature of biochar. Soil and biochar pH, biochar applied rate, and latitude also influence soil GHG fluxes, but to a more limited extent. Our findings provide a scientific basis for developing more rational strategies toward widespread adoption of biochar as a soil amendment for climate change mitigation. [ABSTRACT FROM AUTHOR]

A process development unit (PDU) for amine-based post-combustion carbon capture located at Clean Coal Technologies Centre in Zabrze, Poland, was used to validate split-stream configuration. A PDU having capacity up to 100 m³n /h was designed to test the amine scrubbing carbon capture process from flue gases or mixtures of technical gases. Flexible process flow sheet of the unit allowed investigation of the split flow process. The split-flow flowsheet modification was compared with a standard system for chemical absorption-based CO2 capture. The tests were conducted using well-accepted baseline solvent: 30 wt% aqueous monoethanolamine solution. The flow sheet modification resulted in a decrease of reboiler heat duty by ~1.6% and an increase in CO2 recovery by ~1.2 p.p. Split-flow process modification was examined together with standard process flow sheet, and vast number of process parameters recorded during the trials have been presented. The explanation of beneficial effects of split-flow designs have been shown together with detailed analysis of experimental trials carried out using PDU for amine-based post-combustion carbon capture. This paper is also a valuable source of experimental data useful during validation of models. [ABSTRACT FROM AUTHOR]

Power-to-Methane is a technically feasible process that can store large amounts of electrical energy for a long time period. The produced gas of the process can be fed into the natural gas grid or used as fuel. An essential part of the process chain is the catalytic methanation of carbon dioxide. In the methanation process, carbon dioxide and hydrogen are converted into methane and water vapor. Carbon dioxide can be won from industrial processes, ambient air or biogas plants. In this paper, fundamentals and process developments of methanation of carbon dioxide are described. [ABSTRACT FROM AUTHOR]

The Front Cover shows an amino‐modified copper(I) oxide catalyst reduces the Gibbs free energy for electrocatalytic reduction of carbon dioxide to ethylene. The roller coasters and tracks represent the catalysts and the Gibbs free energy, respectively. In their Full Paper, H. Deng et al, illustrate that the modification of amino on copper(I) oxide promotes the hydrogenation of *CO to *CHO, which is the rate‐determining step for the formation of ethylene. This work presents an amino‐assisted carbon‐carbon coupling mechanism during electroreduction of carbon dioxide to multi‐carbon products. More information can be found in the Full Paper by H. Deng et al. [ABSTRACT FROM AUTHOR]

This paper provides the theoretical calculation results of thermodynamic and transport properties of CO2, CO2–O2 mixture, CO2–H2 mixture under thermal equilibrium condition at temperatures of 300 to 30,000 K and at pressures of 0.1 to 10 MPa. The gas CO2 is one of the candidates for the environmentally benign arc-quenching medium in a circuit breaker. Furthermore, the effect of additional gases O2 and H2 on the thermodynamic and transport properties of CO2 was also investigated in this paper. The hydrogen atom included CO2 is similar to the polymer ablated vapor in switching devices. First, equilibrium compositions of CO2, CO2–O2 mixture, CO2–H2 mixture were calculated through the Gibbs free energy minimization method. Second, thermodynamic properties were computed using the calculated composition. Finally, transport properties were calculated by the first-order approximation of Chapman– Enskog method using the collision integrals between species. Inclusion of H2 increases the electrical conductivity of CO2 in the range 3000 to 6000 K because CHO molecules produced in this temperature range emit more electrons due to the lower ionization potential of CHO. It also increases the thermal conductivity of CO2 especially due to dissociation reactions of H2 around 3900 K and ionization of H around 15,000 K. These properties provided here can be used for CO2 thermal plasma simulation. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(4): 18–29, 2008; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20467 [ABSTRACT FROM AUTHOR]

Abatement of CO2 emission is one of the most important issues in the 21st century regarding preservation of the earth environment. This paper addresses a utility operations planning problem for distributed energy management systems (DEMSs), where we are to obtain optimal plans that minimize both costs and CO2 emissions. A DEMS consists of multiple entities that seek their own economic profits. In this paper, we give a mathematical formulation of the utility operations planning problem for each entity, and propose an energy trading market, which utlizes a multi-attribute auction protocol in order to deal with both a price and a CO2 emission rate. Experimental results show that collaboration among entities through the market provides a more profitable plan for each entity and abatement of CO2 emission is also achieved. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(4): 54–63, 2008; Published online in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/eej.20418 [ABSTRACT FROM AUTHOR]

Many uncertainties remain regarding how climate change will alter the structure and function of forest ecosystems. At the Aspen FACE experiment in northern Wisconsin, we are attempting to understand how an aspen/birch/maple forest ecosystem responds to long-term exposure to elevated carbon dioxide (CO2) and ozone (O3), alone and in combination, from establishment onward. We examine how O3 affects the flow of carbon through the ecosystem from the leaf level through to the roots and into the soil micro-organisms in present and future atmospheric CO2 conditions. We provide evidence of adverse effects of O3, with or without co-occurring elevated CO2, that cascade through the entire ecosystem impacting complex trophic interactions and food webs on all three species in the study: trembling aspen ( Populus tremuloides Michx .), paper birch ( Betula papyrifera Marsh), and sugar maple ( Acer saccharum Marsh). Interestingly, the negative effect of O3 on the growth of sugar maple did not become evident until 3 years into the study. The negative effect of O3 effect was most noticeable on paper birch trees growing under elevated CO2. Our results demonstrate the importance of long-term studies to detect subtle effects of atmospheric change and of the need for studies of interacting stresses whose responses could not be predicted by studies of single factors. In biologically complex forest ecosystems, effects at one scale can be very different from those at another scale. For scaling purposes, then, linking process with canopy level models is essential if O3 impacts are to be accurately predicted. Finally, we describe how outputs from our long-term multispecies Aspen FACE experiment are being used to develop simple, coupled models to estimate productivity gain/loss from changing O3. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the effects of elevated carbon dioxide [CO2] and ozone [O3] and their interaction on wood chemistry and anatomy of five clones of 3-year-old trembling aspen (Populus tremuloides Michx.). Wood chemistry was studied also on paper birch (Betula papyrifera Marsh.) and sugar maple (Acer saccharum Marsh.) seedling-origin saplings of the same age. Material for the study was collected from the Aspen Free-Air CO2 Enrichment (FACE) experiment in Rhinelander, WI, USA, where the saplings had been exposed to four treatments: control (C; ambient CO2, ambient O3), elevated CO2 (560ppm during daylight hours), elevated O3 (1.5 × ambient during daylight hours) and their combination (CO2 + O3) for three growing seasons (1998–2000). Wood chemistry responses to the elevated CO2 and O3 treatments differed between species. Aspen was most responsive, while maple was the least responsive of the three tree species. Aspen genotype affected the responses of wood chemistry and, to some extent, wood structure to the treatments. The lignin concentration increased under elevated O3 in four clones of aspen and in birch. However, elevated CO2 ameliorated the effect. In two aspen clones, nitrogen in wood samples decreased under combined exposure to CO2 and O2. Soluble sugar concentration in one aspen clone and starch concentration in two clones were increased by elevated CO2. In aspen wood, α-cellulose concentration changed under elevated CO2, decreasing under ambient 03 and slightly increasing under elevated O3. Hemicellulose concentration in birch was decreased by elevated CO2 and increased by elevated O3. In aspen, elevated O3 induced statistically significant reductions in distance from the pith to the bark and vessel lumen diameter, as well as increased wall thickness and wall percentage, and in one clone, decreased fibre lumen diameter. Our results show that juvenile wood properties of broadleaves, depending on species and genotype, were altered by atmospheric gas concentrations predicted for the year 2050 and that CO2 ameliorates some adverse effects of elevated O3 on wood chemistry. [ABSTRACT FROM AUTHOR]

We studied the three-way interaction of elevated CO2, nitrogen (N), and temperature ( T), and the two-way interaction of elevated CO2 and early-season defoliation on the secondary chemistry and resistance of Eurasian silver birch ( Betula pendula) and North American paper birch ( B. papyrifera) against the Eurasian hare ( Lepus timidus) and the North American eastern cottontail rabbit ( Sylvilagus floridanus), respectively. Elevated CO2 decreased the palatability of winter-dormant silver and paper birch stems to both hares and rabbits, respectively. But the effect on hares was only apparent at intermediate levels of N fertilization. Elevated T had no effect on palatability. The effects of elevated CO2, N, and T on levels of silver birch bark phenolics and terpenoids were dominated by two-way interactions between N and CO2, and N and T. Generally, however, N amendments elicited a parabolic response in carbon partitioning to most biosynthetic classes of silver birch phenolics (i.e. highest concentrations occurring at intermediate N). CO2 elevation was most enhancing at highest levels of N. On the other hand, T increases, more often than not, elicited reductions in phenolics, but especially so at the highest N level. In the case of B. papyrifera, elevated CO2 increased carbon partitioning to Folin-Denis stem and branch phenolics and condensed tannins. Early-season defoliation, on the other hand, had no effect on phenolics and tannins but lowered both N and energy levels of branches. Elevated CO2 substantially ameliorated the negative effects of severe defoliation on tree growth. These results support the hypothesis that continuing anthropogenic alterations of the atmosphere may trigger significant changes in plant phenotypic resistance to mammalian herbivores owing to an increasing net carbon balance between the highly vagile supply and demand capacities of plant carbon sources and sinks. [ABSTRACT FROM AUTHOR]

Abstract1. Does enhanced whole-plant CO2 exchange in moderately low to high light occur at the cost of greater CO2 loss rates at very-low light levels? We examined this question for first-year seedlings of intolerant Populus tremuloides and Betula papyrifera, intermediate Betula alleghaniensis, and tolerant Ostrya virginiana and Acer saccharum grown in moderately low (7·3% of open-sky) and low (2·8%) light. We predicted that, compared with shade-tolerant species, intolerant species would have characteristics leading to greater whole-plant CO2 exchange rates in moderately low to high light levels, and to higher CO2 loss rates at very-low light levels. 2. Compared with shade-tolerant A. saccharum, less-tolerant species grown in both light treatments had greater mass-based photosynthetic rates, leaf, stem and root respiration rates, leaf mass:plant mass ratios and leaf area:leaf mass ratios, and similar whole-plant light compensation points and leaf-based quantum yields. 3. Whole-plant CO2 exchange responses to light (0·3–600 µmol quanta m-2 s-1) indicated that intolerant species had more positive CO2 exchange rates at all but very-low light (< 15 µmol quanta m-2 s-1). In contrast, although tolerant A. saccharum had a net CO2 exchange disadvantage at light > 15 µmol quanta m-2 s-1, its lower respiration resulted in lower CO2 losses than other species at light < 15 µmol quanta m-2 s-1. 4. Growth scaled closely with whole-plant CO2 exchange characteristics and especially with integrated whole-plant photosynthesis (i.e. leaf mass ratio × in situ leaf photosynthesis). In contrast, growth scaled poorly with leaf-level quantum yield, light compensation point, and light-saturated photosynthetic rate. 5. Collectively these patterns indicated... [ABSTRACT FROM AUTHOR]

ABSTRACT This paper reports an investigation into the effect of carbon dioxide (CO2) gas on various ultra wideband channel coefficients. Measurements were conducted using apparatus consisting of a rubberized tube (6 mm diameter) connected to a source of CO2 or nitrogen (N2). For support, the rubberized tube was wrapped twice around a PVC pipe (160 mm diameter). The rubberized tube was flushed with 100% CO2 several times before being sealed in the tube at atmospheric pressure. In between measurement trials, removal of CO2 was achieved by flushing with pure nitrogen. A Vector Network Analyzer (VNA) using two identical directional antennas, with the wrapped section of tubing placed in-between, measured the channel coefficients over ultra wideband frequency spans of (0.3-8) GHz and (1-2) GHz. Significant magnitude differences between the baseline condition and that of CO2 were observed. We found the same signature of difference curves over the same frequency spans for different measurements. Difference in shape in the frequency band of (1-2) GHz is the same as that of the measured difference over 1-2 GHz in entire frequency band of 300 MHz to 8 GHz for the measured channel coefficients. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1543-1546, 2016 [ABSTRACT FROM AUTHOR]

In this work, we exploit a new formulation of the potential energy and of the related computational procedures, which embodies the coupling between the intra and intermolecular components, to characterize possible propensities of the collision dynamics in energy transfer processes of interest for simulation and control of phenomena occurring in a variety of equilibrium and nonequilibrium environments. The investigation reported in the paper focuses on the prototype CO2-N2 system, whose intramolecular component of the interaction is modeled in terms of a many body expansion while the intermolecular component is modeled in terms of a recently developed bonds-as-interacting-molecular-centers' approach. The main advantage of this formulation of the potential energy surface is that of being (a) truly full dimensional (i.e., all the variations of the coordinates associated with the molecular vibrations and rotations on the geometrical and electronic structure of the monomers, are explicitly taken into account without freezing any bonds or angles), (b) more flexible than other usual formulations of the interaction and (c) well suited for fitting procedures better adhering to accurate ab initio data and sensitive to experimental arrangement dependent information. Specific attention has been given to the fact that a variation of vibrational and rotational energy has a higher (both qualitative and quantitative) impact on the energy transfer when a more accurate formulation of the intermolecular interaction (with respect to that obtained when using rigid monomers) is adopted. This makes the potential energy surface better suited for the kinetic modeling of gaseous mixtures in plasma, combustion and atmospheric chemistry computational applications. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Methanol is a very useful platform molecule and liquid fuel. Electrocatalytic reduction of CO2 to methanol is a promising route, which currently suffers from low efficiency and poor selectivity. Herein we report the first work to use a Mo-Bi bimetallic chalcogenide (BMC) as an electrocatalyst for CO2 reduction. By using the Mo-Bi BMC on carbon paper as the electrode and 1-butyl-3-methylimidazolium tetrafluoroborate in MeCN as the electrolyte, the Faradaic efficiency of methanol could reach 71.2 % with a current density of 12.1 mA cm−2, which is much higher than the best result reported to date. The superior performance of the electrode resulted from the excellent synergistic effect of Mo and Bi for producing methanol. The reaction mechanism was proposed and the reason for the synergistic effect of Mo and Bi was discussed on the basis of some control experiments. This work opens a way to produce methanol efficiently by electrochemical reduction of CO2. [ABSTRACT FROM AUTHOR]

Methanol is a very useful platform molecule and liquid fuel. Electrocatalytic reduction of CO2 to methanol is a promising route, which currently suffers from low efficiency and poor selectivity. Herein we report the first work to use a Mo-Bi bimetallic chalcogenide (BMC) as an electrocatalyst for CO2 reduction. By using the Mo-Bi BMC on carbon paper as the electrode and 1-butyl-3-methylimidazolium tetrafluoroborate in MeCN as the electrolyte, the Faradaic efficiency of methanol could reach 71.2 % with a current density of 12.1 mA cm−2, which is much higher than the best result reported to date. The superior performance of the electrode resulted from the excellent synergistic effect of Mo and Bi for producing methanol. The reaction mechanism was proposed and the reason for the synergistic effect of Mo and Bi was discussed on the basis of some control experiments. This work opens a way to produce methanol efficiently by electrochemical reduction of CO2. [ABSTRACT FROM AUTHOR]

Biochar as a carbon-rich coproduct of pyrolyzing biomass, its amendment has been advocated as a potential strategy to soil carbon (C) sequestration. Updated data derived from 50 papers with 395 paired observations were reviewed using meta-analysis procedures to examine responses of soil carbon dioxide (CO2) fluxes, soil organic C (SOC), and soil microbial biomass C (MBC) contents to biochar amendment. When averaged across all studies, biochar amendment had no significant effect on soil CO2 fluxes, but it significantly enhanced SOC content by 40% and MBC content by 18%. A positive response of soil CO2 fluxes to biochar amendment was found in rice paddies, laboratory incubation studies, soils without vegetation, and unfertilized soils. Biochar amendment significantly increased soil MBC content in field studies, N-fertilized soils, and soils with vegetation. Enhancement of SOC content following biochar amendment was the greatest in rice paddies among different land-use types. Responses of soil CO2 fluxes and MBC to biochar amendment varied with soil texture and pH. The use of biochar in combination with synthetic N fertilizer and waste compost fertilizer led to the greatest increases in soil CO2 fluxes and MBC content, respectively. Both soil CO2 fluxes and MBC responses to biochar amendment decreased with biochar application rate, pyrolysis temperature, or C/N ratio of biochar, while each increased SOC content enhancement. Among different biochar feedstock sources, positive responses of soil CO2 fluxes and MBC were the highest for manure and crop residue feedstock sources, respectively. Soil CO2 flux responses to biochar amendment decreased with pH of biochar, while biochars with pH of 8.1-9.0 had the greatest enhancement of SOC and MBC contents. Therefore, soil properties, land-use type, agricultural practice, and biochar characteristics should be taken into account to assess the practical potential of biochar for mitigating climate change. [ABSTRACT FROM AUTHOR]

The global warming is directly related to the increased greenhouse gas emissions from both natural and anthropogenic origins. There has been a drastic rise in the concentration of CO2 and other greenhouse gases since the industrial revolution primarily due to the intensifying consumption of fossil fuels. With the need to reduce carbon emissions and mitigate global warming certain strategies relating to carbon capturing and sequestration are indispensable. This paper comprehensively describes several physicochemical, biological and geological routes for carbon capture and sequestration. The trend of the increase in greenhouse gases over the years is illustrated along with the global statistics for fossil fuels usage and biofuels production. The physicochemical carbon capturing technologies discussed include absorption, adsorption, membrane separation and cryogenic distillation. The algal and bacterial systems, dedicated energy crops and coalbed methanogenesis have been vividly explained as the biological routes for carbon sequestration. The geological carbon sequestering route centers on biochar application and oceanic carbon storage. A systematic survey has been made on the origin and impact of greenhouse gases along with the potential for sequestration based on some fast-track and long-term sequestration technologies. [ABSTRACT FROM AUTHOR]

First tunnel boring machine to start soon at the GKI / Erste Tunnelvortriebsmaschine am GKI vor dem Start Tunnel ground breaking for the Stadtbahn extension in Dortmund / Tunnelanschlag für Stadtbahnerweiterung in Dortmund Semmering Base Tunnel: start of construction of the access shafts in the Fröschnitzgraben / Semmering-Basistunnel: Startschuss für Bau der Zugangsschächte im Fröschnitzgraben Variable Density Technology - game changer for Kuala Lumpur / Variable Density Technologie - Game Changer für Kuala Lumpur ILF is working on the longest rail tunnel in Georgia / ILF arbeitet am längsten Eisenbahntunnel in Georgien Breakthrough of the first tunnel for the Terzo Valico railway line in Italy / Durchbruch des ersten Tunnels der italienischen Eisenbahnlinie Terzo Valico European Parliament confirms 1.18 b. Euros of financing for the Brenner Base Tunnel / Europäisches Parlament bestätigt Finanzierung von 1,18 Mrd. Euro für den Brenner Basistunnel More than 110 projects entered for the ITA Award 2015 / Mehr als 110 Projekte für den ITA Award 2015 eingereicht Call for papers - Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der 'Geomechanics and Tunnelling' [ABSTRACT FROM AUTHOR]

An effective and long-term treatment of cellulite has not been well established. To our knowledge, no review has analyzed the whole range of treatments for this condition. We conducted a review of in vivo studies on humans adopting the key words 'cellulite' and 'treatment.' The studies were included according to eligibility criteria. We performed an analysis to estimate the overall effect of cellulite treatments from clinical studies. Medline library was screened up to December 2014 to identify eligible studies. We included 73 original studies in the present review. All of them were clinical studies, in most of them, only women were recruited. Above the studies searched up, 66 tested the effectiveness of an exclusive treatment performed without the association to other procedures: 11 topical agents, 10 shock-wave therapy, 10 radio frequency, eight laser therapy, five oral therapy, four manual massage therapy, three carbon dioxide therapy, two compressive therapy, two infrared therapy, one dermabrasion, and 11 devices that use an association of multiple treatments. Seven papers tested a combination of two or more treatments. The mean difference of clinical morphologic features and ultrastructural changes between the treated group and the controlled showed significant heterogeneity between studies. It is still difficult to indicate an exclusive and effective single treatment for this condition. Our analysis purposed to obtain a complete overview of the available treatments in cellulite reduction. [ABSTRACT FROM AUTHOR]

In China, iron and steel plants are confronted with increased demands to reduce their CO2 emissions. Data on CO2 emissions derived from iron and steel making is a basic requirement for a certificate of CO2 reduction. In the current paper, carbon flows from blast furnace and basic oxygen furnace (BF-BOF) steelmaking systems are analyzed using Material Flow Analysis (MFA). The computation method is built and used to calculate CO2 emissions in three steel works. The amount of carbon flow and CO2 emission per ton of product ( [ABSTRACT FROM AUTHOR]

This paper reports the result of a fireside corrosion test carried out on four low alloyed ferritic alloys at 650 °C for 1000 h. The combustion gases were derived from co-firing cereal co-product with a UK coal. Synthetic deposits were used to assess the influence of the deposit compositions. The samples were examined using an ESEM/EDX. To quantify the metal damage the pre-exposure micrometre measurements were compared with the post-exposure image analyser measurements on sample cross-sections. The median metal damage of the alloys showed the following ranking (most to the least damage): 15Mo3>T22> T23> T91. [ABSTRACT FROM AUTHOR]

This paper demonstrates that the CO2 conversion in a dielectric barrier discharge rises drastically upon addition of Ar or He, and the effect is more pronounced for Ar than for He. The effective CO2 conversion, on the other hand, drops upon addition of Ar or He, which is logical due to the lower CO2 content in the gas mixture, and the same is true for the energy efficiency, because a considerable fraction of the energy is then consumed into ionization/excitation of Ar or He atoms. The higher absolute CO2 conversion upon addition of Ar or He can be explained by studying in detail the Lissajous plots and the current profiles. The breakdown voltage is lower in the CO2/Ar and CO2/He mixtures, and the discharge gap is more filled with plasma, which enhances the possibility for CO2 conversion. The rates of electron impact excitation-dissociation of CO2, estimated from the electron densities and mean electron energies, are indeed higher in the CO2/Ar and (to a lower extent) in the CO2/He mixtures, compared to the pure CO2 plasma. Moreover, charge transfer between Ar+ or Ar2+ ions and CO2, followed by electron-ion dissociative recombination of the CO2+ ions, might also contribute to, or even be dominant for the CO2 dissociation. All these effects can explain the higher CO2 conversion, especially upon addition of Ar, but also upon addition of He. [ABSTRACT FROM AUTHOR]

AbstractThis paper reviews two decades of effort by the scientific community in a search for predictive understanding of plant responses to elevated [CO2]. To evaluate the progress of research in leaf photosynthesis, plant respiration, root nutrient uptake, and carbon partitioning, we divided scientific activities into four phases: (I) initial assessments derived from our existing knowledge base to provide frameworks for experimental studies; (II) experimental tests of the initial assessments; (III) in cases where assessments were invalidated, synthesis of experimental results to stimulate alternative hypotheses and further experimentation; and (IV) formation of new knowledge. This paper suggests that photosynthetic research may have gone through all four phases, considering that (a) variable responses of photosynthesis to [CO2] are generally explainable, (b) extrapolation of leaf-level studies to the global scale has been examined, and (c) molecular studies are under way. Investigation of plant respiratory responses to [CO2] has reached the third phase: experimental results have been accumulated, and mechanistic approaches are being developed to examine alternative hypotheses in search for new concepts and/or new quantitative frameworks to understand respiratory responses to elevated [CO2]. The study of nutrient uptake kinetics is still in the second phase: experimental evidence has contradicted some of the initial assessments, and more experimental studies need to be designed before generalizations can be made. It is quite unfortunate that we have not made much progress in understanding mechanisms of carbon partitioning during the past two decades. This is due in part to the fact that some of the holistic theories, such as functional balance and optimality, have not evolved into testable hypotheses to guide experimental studies. This paper urges modelers to play an increasing role in plant–CO2 research by disassembling these existing theories into hypotheses and urges experimentalists to design experiments to examine these holistic concepts. [ABSTRACT FROM AUTHOR]

The scaling of CO2 and water vapour transfer from leaf to canopy dimensions was achieved by integrating mechanistic models for physiological (photosynthesis, stomatal conductance and soil/root and bole respiration) and micrometeorological (radiative transfer, turbulent transfer and surface energy exchanges) processes. The main objectives of this paper are to describe a canopy photosynthesis and evaporation model for a temperate broadleaf forest and to test it against field measurements. The other goal of this paper is to use the validated model to address some contemporary ecological and physiological questions concerning the transfer of carbon and water between forest canopies and the atmosphere. In particular, we examine the role of simple versus complex radiative transfer models and the effect of environmental (solar radiation and CO2) and ecophysiological (photosynthetic capacity) variables on canopy-scale carbon and water vapour fluxes. [ABSTRACT FROM AUTHOR]

In this paper, we used a theoretical model for the variation of Eulerian porosity, which takes into account the adsorption process known to be the main mechanism of production or sequestration of gas in many reservoir of coal. This process is classically modeled using Langmuir's isotherm. After implementation in Code_Aster, a fully coupled thermo-hydro-mechanical analysis code for structures calculations, we used numerical simulations to investigate the influence of coal's hydro-mechanical properties (Biot's coefficient, bulk modulus), Langmuir's adsorption parameters, and the initial liquid pressure in rock mass during CO2 injection in coal. These simulations showed that the increase in the values of Langmuir's parameters and Biot's coefficient promotes a reduction in porosity because of the adsorption process when the gas pressure increases. Low values of bulk modulus increase the positive effect (i.e., increase) of hydro-mechanical coupling on the porosity evolution. The presence of high initial liquid pressure in the rock mass prevents the progression of injected gas pressure when CO2 dissolution in water is taken into account. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper proposes a new methodology for carbon price forecasting. It posits a finite distributed lag (FDL) model and then applies a GA-ridge algorithm to determine a set of proper predictors with coefficient estimates. An empirical study was conducted in the European Union Greenhouse Gas Emissions Trading market, revealing that our methodology not only yields good forecasting results but also provides some interesting analysis on the carbon price market. It turns out that the combination of the FDL model and GA-ridge algorithm is desirable for forecasting and analyzing the complicated carbon price market because of its capability of selecting proper predictors from a class of predictors of itself. [ABSTRACT FROM AUTHOR]

This work focuses on carbonation-induced corrosion in concrete. This paper presents specific experiments which were developed in order to assess the influence of both pre-existing oxides layer at the surface of the steel bars and steel-concrete interface condition on active corrosion. Two types of active corrosion are studied: Microcell corrosion and galvanic corrosion. Results show that pre-existing oxide layer contributes to reduce both galvanic and microcell corrosion. Steel-concrete interface defect leads to a strong increase in galvanic corrosion but does not affect significantly microcell corrosion in carbonated concrete. The quantity of pre-existing oxides is highly scattered and these scatters can be superior to the mass of new oxides formed during relatively short-term corrosion tests in natural condition which makes mass loss analysis very difficult. [ABSTRACT FROM AUTHOR]

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In this paper, time-of-flight secondary ion mass spectrometry (ToF-SIMS) was investigated as a tool for analyzing changes on mineral grains (siderite and ankerite) caused by dissolution and precipitation processes. Carbon dioxide capture and sequestration is a technique investigated for its possible employment in the reduction of the amount of anthropogenic CO2 gas emitted into the atmosphere. Deep saline aquifers are one option for storing CO2 gas streams produced, e.g. by the combustion of fossil fuels at power plants. These gas streams contain different impurities depending on their origin, among them O2, NOx, SOx in addition to CO2. Geochemical experiments under in-situ pressure and temperature conditions of possible geological storage sites were performed, and preparation techniques for the solid products were developed for 3D analysis. The results show that it is possible to analyze the alterations that occur on the surface of siderite grains during CO2 or CO2/O2 exposures under CO2 storage site conditions. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

1. Elevated concentrations of carbon dioxide and tropospheric ozone pose important threats to the abundance, diversity, and composition of forest arthropod communities. In turn, modification of arthropod communities may alter forest health, productivity, and ecosystem services. 2. We studied the independent and interactive effects of elevated CO2 (eCO2) and elevated O3 (eO3) on the abundance, species richness, and community composition of herbivorous arthropods in stands of trembling aspen and paper birch at the Aspen Free Air CO2 Enrichment (FACE) site in northern Wisconsin, USA. We conducted timed, visual surveys of canopy arthropods during each of the summers of 2005, 2006, and 2007. 3. We examined 26 983 arthropods on aspen and 8344 arthropods on birch across the fumigation treatments. Elevated CO2 and eO3 had species-specific and temporally variable (i.e. idiosyncratic) effects on aspen and birch arthropod abundance and species richness. Weak, idiosyncratic effects of eCO2 and eO3 on herbivorous arthropod abundance and species richness did not significantly alter aspen arthropod community composition but occasionally altered birch insect community composition. Few interactive effects of CO2 and O3 were observed. 4. Growing evidence suggests that the effects of eCO2 and eO3 on communities of insects are difficult to predict because responses are generally weak and species- and time-specific. Although studies to date suggest that impacts of future atmospheres on insect community metrics are likely to be minimal, the possibility remains that effects on particularly important or susceptible species may cascade to alter trophic interactions and, ultimately, ecosystem processes. [ABSTRACT FROM AUTHOR]

Ablative fractional carbon dioxide (CO2) lasers have been widely used for several types of cosmetic dermatosis. A number of previous studies have evaluated this technique in animals or human beings by observing morphologic changes using an invasive modality such as skin biopsy. In this study, we assessed in vivo skin changes after CO2 ablative fractional laser treatment in a mouse model using noninvasive imaging modalities (Folliscope® and Visioscan 98®), and each results was compared with data from histologic examination. An ablative fractional CO2 laser was applied with different pulse energy between 7 to 35 mJ/microspot. As results of above methods, we also confirmed that the CO2 ablative fractional laser generated injuries with increasing width and depth with increasing pulse energy. Although numerous papers have described application of this laser in vivo skin specimens, our study evaluated the feasibility of using relative noninvasive imaging modalities for assessing the outcome of laser ablation. Based on our data, we suggest that these technologies may be useful alternative modalities for assessing laser ablation that are easier to perform and less invasive than skin biopsy. [ABSTRACT FROM AUTHOR]

Purpose: Breath analysis has a potential prospect to benefit the medical field based on its perceived advantages to become a point-of-care, easy to use, and cost-effective technology. Early studies done by mass spectrometry show that volatile organic compounds from human breath can represent certain disease states of our bodies, such as lung cancer, and revealed the potential of breath analysis. But mass spectrometry is costly and has slow-turnaround time. The authors' goal is to develop a more portable and cost effective device based on Raman spectroscopy and hollow core-photonic crystal fiber (HC-PCF) for breath analysis. Methods: Raman scattering is a photon-molecular interaction based on the kinetic modes of an analyte which offers unique fingerprint type signals that allow molecular identification. HC-PCF is a novel light guide which allows light to be confined in a hollow core and it can be filled with a gaseous sample. Raman signals generated by the gaseous sample (i.e., human breath) can be guided and collected effectively for spectral analysis. Results: A Raman-cell based on HC-PCF in the near infrared wavelength range was developed and tested in a single pass forward-scattering mode for different gaseous samples. Raman spectra were obtained successfully from reference gases (hydrogen, oxygen, carbon dioxide gases), ambient air, and a human breath sample. The calculated minimum detectable concentration of this system was ~15 parts per million by volume, determined by measuring the carbon dioxide concentration in ambient air via the characteristic Raman peaks at 1286 and 1388 cm-1 . Conclusions: The results of this study were compared to a previous study using HC-PCF to trap industrial gases and backward-scatter 514.5 nm light from them. The authors found that the method presented in this paper has an advantage to enhance the signal-to-noise ratio (SNR). This SNR advantage, coupled with the better transmission of HC-PCF in the near-IR than in the visible wavelengths led to an estimated seven times improvement in the detection sensitivity. The authors' prototype device also demonstrated a 100-fold improvement over a recently reported detection limit of a reflective capillary fiber-based Raman cell for breath analysis. Continued development is underway to increase the detection sensitivity further to reach practical clinical applications. [ABSTRACT FROM AUTHOR]

This perspective paper introduces the changing landscape for green & sustainable chemical production, by discussing three key aspects, in relation especially to the possible routes in using biomass and CO2 as new raw materials: i) introduction of renewable energy in the chemical production chain, ii) from biorefineries to bio-factories, and iii) moving to a new landscape for raw materials. It is remarked how they are challenging, but at the same time open chemical industry to innovation and competiveness. This is a critical element particularly in the transitions to new economies. [ABSTRACT FROM AUTHOR]

An important component of the assimilation of radiance observations from the AIRS and IASI satellite instruments is the radiative transfer modelling. Currently, the RTTOV model used in the ECMWF IFS system uses a fixed value for CO 2. Neglecting the spatio-temporal variability of CO 2 introduces an error in the simulation of the satellite radiances, which could affect the quality of the analyses and forecasts. The current assumption is that variational bias correction corrects most of this error and therefore minimizes the impact on the forecast scores. This paper investigates the possibility of modelling CO 2 within the IFS to improve the radiative transfer modelling. Results show that the required bias correction is significantly reduced when using more realistic CO 2 values. The impact on the analysis quality and forecast scores is mostly neutral with some indication of improvement in the Tropics and the stratosphere. [ABSTRACT FROM AUTHOR]

The article presents abstracts on papers related to chemistry including "Transition-Metal-Free Catalytic Reduction of Carbon Dioxide," by F. G. Fontaine, M. A. Courtemanche, and M. A. Lègarè, "Effective Cancer Cell Killing by Hydrophobic Nanovoid-Enhanced Cavitation under Safe Low-Energy Ultrasound," by Y. Zhao and colleagues, and "Oxidative Coupling of Organoboron Compounds," by R. N. Dhital and H. Sakurai.

The paper reports on a routine to extract the composition of multi-component mixtures from their Raman spectra at elevated pressures. The strategy is based on fitting weighted Raman spectra of the pure compounds to the measured Raman spectrum of the mixture, also considering the effects of intermolecular interactions onto the Raman spectra by applying Gaussian and Voigt profile deconvolution of the Raman peaks. Thereby, an improved accuracy compared to previous evaluation strategies could be obtained. The more accurate data of the ternary mixtures of carbon dioxide, water and organic solvents are presented. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Pentafluorophenyl end-capped poly(ethylene glycol) (PF-PEG-PF) aqueous solution shows a lower critical solution temperature (LCST), which is sensitive to the type of gases dissolved in the solution. LCST increases from 24.5 to 26 °C when dissolved carbon dioxide is replaced by oxygen. The transparent-to-turbid transition is reversibly observed when the dissolved carbon dioxide in the PF-PEG-PF aqueous solution is exchanged with oxygen, and vice versa, at 24.5 °C. 19F NMR and 1H NMR spectra of the PF-PEG-PF in D2O suggest that 1) dehydration of PEG is the main reason of developing LCST of the PF-PEG-PF aqueous solution, 2) minute differences in the intermolecular interactions, as demonstrated by changes in the chemical shift of the PF-PEG-PF peaks, induce such a difference in LCST. This paper provides a new insight in designing a stimuli-responsive polymer in that fine tuning of a phase transition can be controlled by the type of dissolved gas. [ABSTRACT FROM AUTHOR]

The article presents abstracts on papers related to lipids including "Inhibition of lipid oxidation and rancidity in precooked pork patties by radical-scavenging licorice (Glycyrrhiza glabra) extract," by J. Jiang and colleagues, "Enhancing the release of the antioxidant tocopherol from polypropylene films," by C. Lopez de Decastillo and colleagues, and "Tocol composition and supercritical carbon dioxide extraction of lipids from barley pearling flour," by F. Temelli and colleagues.

The solvent-free production of edible oils from oilseeds is steadily gathering more importance. Therefore, gas-assisted pressing is an innovative process. Knowlegde of the diffusion kinetics of the gas is essential in order to optimize the process. In this paper experimentally obtained molecular diffusion coefficients of CO2 in pure rapeseed oil as well as effective diffusion coefficients of CO2 within the oil of oil-bearing rapeseed presscake are presented. The acquired diffusion coefficients are compared to literature correlations and adjustments are presented. Comparison of molecular and effective diffusion coefficients resulted in an diffusion resistance factor of the surrounding solid of 2.1. [ABSTRACT FROM AUTHOR]

Terrestrial biosphere models can help identify physical processes that control carbon dynamics, including land-atmosphere CO2 fluxes, and have great potential to predict the terrestrial ecosystem response to changing climate. The skill of models that provide continental-scale carbon flux estimates, however, remains largely untested. This paper evaluates the performance of continental-scale flux estimates from 17 models against observations from 36 North American flux towers. Fluxes extracted from regional model simulations were compared with co-located flux tower observations at monthly and annual time increments. Site-level model simulations were used to help interpret sources of the mismatch between the regional simulations and site-based observations. On average, the regional model runs overestimated the annual gross primary productivity (5%) and total respiration (15%), and they significantly underestimated the annual net carbon uptake (64%) during the time period 2000-2005. Comparison with site-level simulations implicated choices specific to regional model simulations as contributors to the gross flux biases, but not the net carbon uptake bias. The models performed the best at simulating carbon exchange at deciduous broadleaf sites, likely because a number of models used prescribed phenology to simulate seasonal fluxes. The models did not perform as well for crop, grass, and evergreen sites. The regional models matched the observations most closely in terms of seasonal correlation and seasonal magnitude of variation, but they have very little skill at interannual correlation and minimal skill at interannual magnitude of variability. The comparison of site vs. regional-level model runs demonstrated that (1) the interannual correlation is higher for site-level model runs, but the skill remains low; and (2) the underestimation of year-to-year variability for all fluxes is an inherent weakness of the models. The best-performing regional models that did not use flux tower calibration were CLM-CN, CASA-GFEDv2, and SIB3.1. Two flux tower calibrated, empirical models, EC-MOD and MOD17+, performed as well as the best process-based models. This suggests that (1) empirical, calibrated models can perform as well as complex, process-based models and (2) combining process-based model structure with relevant constraining data could significantly improve model performance. [ABSTRACT FROM AUTHOR]

The biomass and dynamics of disturbed and degraded tropical forests have mostly been ignored in the recent scientific literature, partly because of a spotlight on old-growth forests but also due to a lack of long-term data from degraded forests. There is a pressing need to understand the rates and patterns of growth, mortality and recruitment in degraded forests, not only because they are increasing in area relative to old-growth forests, but also due to their potential capacity to sequester large amounts of carbon dioxide from the atmosphere. This paper introduces a permanent forest plot network and database, FORMNET- B ( GIVD ID# NA- BZ-001), designed to study the long-term dynamics of disturbed and degraded tropical forests in Belize, Central America. [ABSTRACT FROM AUTHOR]

One of the major challenges for the utilization of carbon dioxide as a chemical feedstock is to devise thermodynamically feasible transformations to valuable chemicals through efficient catalytic processes. In this paper, we examine the feasibility of the experimentally not yet realized direct hydrocarboxylation of alkenes, using computational methods. A conceivable catalytic cycle was devised for the addition of H2 and CO2 to ethene, which affords propionic acid. The corresponding energy profiles were calculated with state-of-the-art DFT methods for three rhodium pincer complexes as potential catalyst. Several junctions within the productive catalytic cycle were identified, leading to competing hydrogenation reactions of ethene or CO2. A profound analysis of the reaction network by means of the energetic span model allowed us to identify parameters that facilitate the carboxylation and that favor it over the hydrogenation reaction. A comparison of the relevant activation energies revealed that two of the three investigated complexes slightly favour the hydrogenation of ethene, but one complex preferentially stays within the carboxylation cycle. [ABSTRACT FROM AUTHOR]

The performance-based durability design of reinforced concrete structures for corrosion of reinforcement is currently limited to the initiation period. That includes modelling the transport processes of chlorides and carbon dioxide into the concrete structure. Up to now, the subsequent time period after depassivation of the reinforcement, in which corrosion propagates, could not be modelled in a comparable manner. The task of the research project presented here, which was part of German Research Unit 537, was to develop a design model that enables a reinforced concrete structure to be designed against reinforcement corrosion for its entire service life. Therefore, a physically well-defined damage model for corrosion propagation was chosen as a basis. All system parameters in the damage model were investigated on the basis of numerical and laboratory studies carried out in the subprojects of the research unit. Statistical analysis allowed the simplification of the complex damage model into a user-friendly design model. This paper presents the working steps, the basic results of the analysis and the user-friendly full-probabilistic design model for reinforcement corrosion. [ABSTRACT FROM AUTHOR]