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Contents 40 I. 40 II. 41 III. 44 IV. 48 V. 49 VI. 49 VII. 52 VIII. 53 53 References 53 SUMMARY: In the last decade, analyses of both molecular and morphological characters, including nodulation, have led to major changes in our understanding of legume taxonomy. In parallel there has been an explosion in the number of genera and species of rhizobia known to nodulate legumes. No attempt has been made to link these two sets of data or to consider them in a biogeographical context. This review aims to do this by relating the data to the evolution of the two partners: it highlights both longitudinal and latitudinal trends and considers these in relation to the location of major land masses over geological time. Australia is identified as being a special case and latitudes north of the equator as being pivotal in the evolution of highly specialized systems in which the differentiated rhizobia effectively become ammonia factories. However, there are still many gaps to be filled before legume nodulation is sufficiently understood to be managed for the benefit of a world in which climate change is rife.

Premature training quenches are usually caused by the transient energy released within the magnet coil as it is energised. Two distinct varieties of disturbances exist. They are thought to be electrical and mechanical in origin. The first type of disturbance comes from non-uniform current distribution in superconducting cables whereas the second one usually originates from conductor motions or micro-fractures of insulating materials under the action of Lorentz forces. All of these mechanical events produce in general a rapid variation of the voltages in the so-called quench antennas and across the magnet coil, called spikes. A statistical method to treat the spatial localisation and the time occurrence of spikes will be presented. It allows identification of the mechanical weak points in the magnet without need to increase the current to provoke a quench. The prediction of the quench level from detailed analysis of the spike statistics can be expected.

This tutorial and review of multi-objective optimization (MOO) gives a detailed explanation of the 5 steps to create, solve, and then select the optimum result. Unlike single-objective optimization, the fifth step of selection or ranking of solutions is often overlooked by the authors of papers dealing with MOO applications. It is necessary to undertake a multi-criteria analysis to choose the best solution. A review of the recent publications using MOO for chemical process engineering problems shows a doubling of publications between 2016 and 2019. MOO applications in the energy area have seen a steady increase of over 20% annually over the last 10 years. The three key methods for solving MOO problems are presented in detail, and an emerging area of surrogate-assisted MOO is also described. The objectives used in MOO trade off conflicting requirements of a chemical engineering problem; these include fundamental criteria such as reaction yield or selectivity; economics; energy requirements; environmental performance; and process control. Typical objective functions in these categories are described, selection/ranking techniques are outlined, and available software for MOO are listed. It is concluded that MOO is gaining popularity as an important tool and is having an increasing use and impact in chemical process engineering.

International audience; Magnitudes of differential stress in the lithosphere, especially in the crust, are still disputed. Earthquake-based stress drop estimates indicate median values ca. 180 MPa, corresponding to a friction angle of ca. 10° to maintain the topographic relief between lowland and plateau for >10 Ma. The relative contribution of crustal strength to total lithospheric strength varies considerably laterally. In the region between lowland and plateau and inside the plateau the depth-integrated crustal strength is approximately equal to the depth-integrated strength of the mantle lithosphere. Simple analytical formulae predicting the lateral variation of depth-integrated stresses agree with numerically calculated stress fields, which show both the accuracy of the numerical results and the applicability of simple, rheology-independent, analytical predictions to highly variable, rheology-dependent stress fields. Our results indicate that (1) crustal strength can be locally equal to mantle lithosphere strength and that (2) crustal stresses must be at least one order of magnitude larger than median stress drops in order to support the plateau relief over a duration of ca. 10 Ma.

Graphite is a stack of honeycomb (graphene) layers bound together by nonlocal, long-range van der Waals (vdW) forces, which are poorly described by density functional theory (DFT) within local or semilocal exchange-correlation functionals. Several approximations have been proposed to add a vdW correction to the DFT total energies (Stefan Grimme (D2 and D3) with different damping functions (D3-BJ), Tkatchenko-Scheffler (TS) without and with self-consistent screening (TS + SCS) effects). Those corrections have remarkly improved the agreement between our results and experiment for the interlayer distance (from 3.9 to 0.6%) [corrected] and high-level random-phase approximation (RPA) calculations for interlayer binding energy (from 69.5 to 1.5%). [corrected]. We report a systematic investigation of various structural, energetic and electron properties with the aforementioned vdW corrections followed by comparison with experimental and theoretical RPA data. Comparison between the resulting relative errors shows that the TS + SCS correction provides the best results; the other corrections yield significantly larger errors for at least one of the studied properties. If considerations of computational costs or convergence problems rule out the TS + SCS approach, we recommend the D3-BJ correction. Comparison between the computed π(z)Γ-splitting and experimental results shows disagreements of 10% or more with all vdW corrections. Even the computationally more expensive hybrid PBE0 has proved unable to improve the agreement with the measured splitting. Our results indicate that improvements of the exchange-correlation functionals beyond the vdW corrections are necessary to accurately describe the band structure of graphite.

This study uses integrated hydrometeorological simulations over the Alabama-Coosa-Tallapoosa (ACT) River Basin in the southeastern United States to understand the impact of climate change on probable maximum precipitation.

En el presente artículo los autores presentan y exponen los resultados obtenidos en la conformación de unlaboratorio virtual asistido con Matlab, para el diseño de un controlador multivariable en una columna dedestilación. Aquí se expone el estudio de un método de desacoplamiento el cual es basado en la matriz defunciones de transferencia del proceso. El aspecto novedoso de la metodología empleada radica en el usode un modelo experimental de una columna de destilación para implementar a través de la simulación uncontrol por desacoplamiento clásico, con una correspondiente evaluación de su desempeño. Los resultadosfinales son mostrados en respuestas temporales usando Matlab. In this paper the authors present and discuss results obtained on the conformation of a practice of virtuallaboratory attended with Matlab, for the design of a multivariavels controller for a distillation column. It'scarried out a study of the decoupling method to be implemented, which is based on the use of the transferfunctions matrix of the researched process. The innovative aspect of the employed methodology lies onthe use of the experimental model of a real distillation column in order to implement, through simulation,techniques of classical decoupling with the correspondent performance evaluation. The final results areshown through the obtained time responses using Matlab.

and (2) improvement and scale-up of the enhanced screening tool, in close collaboration with the research partners. In addition to enabling a better understanding about their own internal processes and activities, the evaluation of the potential of 108 SMEs for eco-innovation provided them with detailed insights about how to reach the potential benefits with industrial symbiosis and green business models. Differently from the identified existing tools, the screening tool proposed in this research aims at supporting companies to understand what their potential for eco-innovation is, combining wider eco-innovation and industrial symbiosis opportunities and green business models, supplemented with a readiness evaluation to explore the existing potential. Despite the high business, innovation and sustainability potential linked with eco-innovation and industrial symbiosis, limited implementation can be observed in small and medium enterprises (SMEs). In order to enhance the implementation of these concepts in SMEs, the main goal of this paper is to propose a screening tool to identify and evaluate SMEs&rsquo potential for eco-innovation, with a special focus on industrial symbiosis and green business models aspects. In order to accomplish this goal, an action research was developed in two cycles: (1) development and testing of the screening prototype

Ultimately, the structure and functioning of marine ecosystems is defined by the transfer of autotrophic production to higher trophic levels and selective consumption of these autotrophs by predators. Hence, feeding regulation via modification of grazing and food incorporation by predators is critical for understanding and predicting the dynamics of ecosystems. In marine ecosystem and biogeochemical models, feeding regulation by consumers is assumed to be mainly dictated by food quality (Q), which is determined using food quality modules (FQMs) that mimic a consumers’ ability to anticipate fitness consequences for feeding on specific prey items. Current FQMs are based on frameworks that a priori identify specific food components, usually nitrogen (N), and/or phosphorus, as limiting. This negates the importance of consumer physiology, and ignores biochemical constrains on the limiting role of chemical elements in animal production. To help address these problems, we propose a new adaptive approach that bases Q on consumers’ capacity for food uptake and metabolic physiology. Uniquely, it (i) has separate pathways for the utilisation of carbon (C) associated with proteins, lipids and carbohydrates, (ii) considers stage-specific structural biochemical requirement of animals, and (iii) does not treat consumers’ structural demand for carbon as a “unitary requirement” but discriminates among the required biochemical forms of carbon. The approach is applicable to all heterotrophs. In the example given here the model has been configured to represent the calanoid copepod Acartia tonsa. Consistent with experimental observation, but unlike previous models, our model predicts the relationship between Q and food C:N to be unimodal with a maximum Q only at the threshold C:N for biomass production. Results suggest that prey C:N ratios may be irrelevant for food quality due to macromolecular biochemical constrains on the utilisation of chemical elements. This result emphasizes the importance of biochemical substances in animal nutrition and production as well as the necessity of developing food quality models able to adapt to the biochemical needs of the consumer.

The promoting effect of Ca on the catalytic performance of Pt0.5-Ge1.5/Al2O3 during propane dehydrogenation (PDH) reaction was studied using experimental methods and kinetic modeling. Different characterization techniques including H2-TPR, NH3-TPD, C3H6-TPD, XPS, BET, CO-chemisorption, CO-DRIFT, and TGA were used to unravel the properties of catalysts. Enhanced propylene selectivity (98.5% Vs 96.4% @ 600 °C and 24 h TOS) and catalyst stability were achieved due to the decrease of acid centers of Al2O3 along with an increase of the degree of alloy formation upon addition of Ca. The experimental data of propane conversion vs. time were successfully fitted with the Deactivation Model with Residual Activity (DMRA), allowing for the calculation of the intrinsic deactivation kinetic parameters for both catalysts. For the Ca-promoted catalyst, a deactivation function of 0.05 h−1 along with a residual activity of 0.82 at 600 °C were obtained. Whereas, for the non-promoted sample, these values were 0.22 h−1 and 0.63, respectively. The activation energy of the PDH reaction for the Pt0.5-Ge1.5/Al2O3-CaO catalyst was slightly higher than that of the unmodified one (74.8 kJ/mol vs. 66.4 kJ/mol) due to the enhanced reduction of the GeOx species on this sample, which enhanced the formation of a Pt-Ge alloy, decreasing the initial activity of the catalyst. However, the higher resistance against the deactivation by coke of the promoted catalyst was invoked to explain the better performance of this catalyst in terms both of activity and selectivity at steady state conditions. The authors gratefully acknowledge the financial support by the Agency for Science, Technology and Research (A*STAR) of Singapore (AME-IRG Grant No. A1783c0016), and the National University of Singapore. Sajjad Rimaz is tankful to A*STAR for the Singapore International Graduate Award (SINGA) scholarship. Peer reviewed