Anhydrous polymeric zinc(II) penta­noate

The structure of the title compound, poly[di-μ-penta­noato-zinc(II)], [Zn{CH3(CH2)3COO}2]n, consists of a three-dimensional polymeric layered network with sheets parallel to the (100) plane, in which tetra­hedrally coordinated zinc(II) ions are connected by penta­noate bridges in a syn–anti arrangement. The hydro­carbon chains are in the fully extended all-trans conformation and are arranged in a tail-to-tail double bilayer

Identification of Model Parameter for the Simulation of SMA Structures Using Full Field Measurements

With the design of new devices with complex geometry and to take advantage of their large recoverable strains, shape memory alloys components (SMA) are increasingly subjected to multiaxial loadings. The development process of SMA devices requires the prediction of their thermomechanical response, where the calibration of the material parameters for the numerical model is an important step. In this work, the parameters of a phenomenological model are extracted from multiaxial and heterogeneous tests carried out on specimens with the same thermomechanical loading history. Finite element analysis enables the computation of numerical strain fields using a thermodynamical constitutive model for shape memory alloys previously implemented in a finite element code. The strain fields computed numerically are compared with experimental ones obtained by DIC to find the model parameters which best matches experimental measurements using a newly developed parallelized mixed genetic/gradient-based optimization algorithm. These numerical simulations are carried out in parallel in a supercomputer to reduce the time necessary to identify the set of identified parameters. The major features of this new algorithm is its ability to identify material parameters of the thermomechanical behavior of shape memory alloys from full-field measurements for various loading conditions (different temperatures, multiaxial behavior, heterogeneous test configurations). It is demonstrated that model parameters for the simulation of SMA structures are thus obtained based on a reduced number of heterogeneous tests at different temperatures.NSF International Institute of Multifunctional Materials for Energy Conversion (IIMEC), award #084108

A Test-and-Not-Treat Strategy for Onchocerciasis Elimination in Loa loa-coendemic Areas: Cost Analysis of a Pilot in the Soa Health District, Cameroon

Background. Severe adverse events after treatment with ivermectin in individuals with high levels of Loa loa microfilariae in the blood preclude onchocerciasis elimination through community-directed treatment with ivermectin (CDTI) in Central Africa. We measured the cost of a community-based pilot using a test-and-not-treat (TaNT) strategy in the Soa health district in Cameroon. Methods. Based on actual expenditures, we empirically estimated the economic cost of the Soa TaNT campaign, including financial costs and opportunity costs that will likely be borne by control programs and stakeholders in the future. In addition to the empirical analyses, we estimated base-case, less intensive, and more intensive resource use scenarios to explore how costs might differ if TaNT were implemented programmatically. Results. The total costs of US$283 938 divided by total population, people tested, and people treated with 42 US$4.0, US$9.2, and US$9.5, respectively. In programmatic implementation, these costs (base-case estimates with less and more intens

Rheological evolution of straw-cattle manure (SCM) treated by dry anaerobic digestion in batch and in continuous pilot reactors

International audienc

Immersion Effect on the Anaerobic Degradation and the Rheological Properties of Straw-Cattle Manure (SCM) at 440 L Batch Pilot Scale Reactor

International audienc

Development of devices for the determination of the rheological properties of coarse biomass treated by dry anaerobic digestion

International audienc

Determination residence time distribution of the solid phase in a dry anaerobic semi-continuous horizontal reactor of 0.5 m3 using innovative 3D printed tracers

International audienceSolid residence time distribution (SRTD) analysis is important in the design, modeling, and operation of solid biomass in continuous dry anaerobic digestion (D-AD) reactors. SRTD analysis could allow the appropriately adjust of the applicable organic charge and the study of unusable volume due to solid accumulation and preferential pathways. The lack of sustainable, environmentally friendly, and cost-effective solid tracers limits the study of solid flow patterns in D-AD digesters. In this study, 3D printing enabled the fabrication of customized Poly Lactic Acid (PLA) tracers with a specific shape to perform SRTD analysis of the semi-continuous digestion of straw-cattle manure (SCM) in a horizontal reactor of 0.5 m3. The recovery of tracers at the reactor outlet allowed the determination of the average SRTD at 29.43 days. Solid convection was predominant over diffusion, indicating that the reactor behaves closer to a plug flow reactor (PFR) rather than a complete stirred tank reactor

Corrigendum to “Quantifying porosity changes in solid biomass waste using a disruptive approach of water retention curves (WRC) for dry anaerobic digestion” [Bioresour. Technol. (2020) 12, 100585]

International audienc