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Incineration bottom ash (IBA) is a by-product generated from incineration of municipal solid wastes, and it is mostly landfilled, especially for fine IBA. Reusing IBA with waste soils as filling materials in civil engineering can be a potential solution. However, the existing studies only focused on the air-cured IBA-soil mixtures in the laboratory, whereas in the field, the mixtures may contact water or immerse in water. Because IBA is rich in sulfates, the stability of IBA-soil mixtures in water may be compromised. Therefore, this study investigated the stability of IBA-marine clay (MC) mixtures in water. Ordinary portland cement (OPC) and granulated blast-furnace slag (GGBS) served as binders to stabilize/solidify IBA-MC. The appearance, strength, mineralogy, and microstructure of IBA-MC, OPC-IBA-MC, and GGBS-IBA-MC were studied. The results showed that all mixtures performed well when cured in air, but some deteriorated after soaking in water. IBA-MC and OPC-IBA-MC subjected to a short precuring period developed significant cracks and strength loss. Long precuring can reduce or eliminate the cracks on specimens during soaking, leading to higher strength. However, GGBS-IBA-MC had no surficial defects and only a slight strength decrease under both precuring periods. The mineralogy and microstructure of IBA-MC and stabilized IBA-MC revealed that the formation and growth of ettringite were responsible for the deterioration of IBA-MC and OPC-IBA-MC soaking in water. [ABSTRACT FROM AUTHOR]

We demonstrate high-throughput label-free single-cell image cytometry and image-based classification of Euglena gracilis (a microalgal species) under different culture conditions. We perform it with our high-throughput optofluidic image cytometer composed of a time-stretch microscope with 780-nm resolution and 75-Hz line rate, and an inertial-focusing microfluidic device. By analyzing a large number of single-cell images from the image cytometer, we identify differences in morphological and intracellular phenotypes between E. gracilis cell groups and statistically classify them under various culture conditions including nitrogen deficiency for lipid induction. Our method holds promise for real-time evaluation of culture techniques for E. gracilis and possibly other microalgae in a non-invasive manner.

Nowadays, research on promoting the dissolution of chalcopyrite is important. As a natural symbiotic mineral of chalcopyrite, arsenopyrite will have an impact on the dissolution of chalcopyrite. This paper shows the influence of arsenopyrite on the dissolution of chalcopyrite in an acidic culture medium. The leaching results showed that adding arsenopyrite increased the leaching concentration of copper by 332 mg/L. The residues showed a decrease in sulfur through X-ray diffraction analysis (XRD) and an increase in dissolution degree through scanning electron microscope (SEM). Electrochemical experiments have shown that the rest potential of arsenopyrite is higher than that of chalcopyrite, so there is a galvanic interaction, and the impact on chalcopyrite is greater than that of arsenopyrite. The polarization curve also proves this. Under the interaction of galvanic couples, the reduction of S0 production and the enhancement of Cu2+ release can promote the dissolution of chalcopyrite. In addition, X-ray photoelectron spectrometer (XPS) analysis under the action of galvanic coupling indicates that more SO42− is generated on the surface of chalcopyrite, replacing Sn2−/S0, and SEM shows a stronger corrosion morphology. All results confirm that the electrochemical effect between arsenopyrite and chalcopyrite promotes the dissolution of chalcopyrite in the acidic culture medium. [ABSTRACT FROM AUTHOR]

The stabilities and associated collapse mechanisms of deep buried unlined elliptical tunnels in cohesive-frictional (c-[phi]) soils with the action of soil weight are investigated by the 'upper-bound finite element method with rigid translatory moving elements' (UBFEM-RTME). The soil masses are assumed to obey the Mohr-Coulomb yield criterion and a nonassociated flow rule. Upper-bound stability coefficients ([[gamma].sub.cr] D/c, where [[gamma].sub.cr] is critical unit weight; D is tunnel height; c is cohesion) are deduced for different values of friction angles ([phi]), dilatancy coefficients ([psi]/[phi] where [psi] is dilation angle), and dimensionless spans (B/D, where B is span). The obtained collapse mechanisms do not extend to the ground surface and are primarily composed of a series of mutually movable rigid blocks. The [[gamma].sub.cr] D/c values increase while the collapse zones decrease with an increasing [phi] and [psi]/[phi] and a decreasing B/D. Key words: deep buried tunnel, upper-bound finite element method, stability coefficient, collapse mechanism, rigid blocks. Les stabilites et les mecanismes d'effondrement associes des tunnels elliptiques non doubles profonds enfouis dans des sols c-[phi] avec l'action du poids de sol sont etudies par ' methode elements finis superieurs avec elements mobiles translatoires rigides (UBFEM-RTME) '. Les masses de sols sont censees obeir aux criteres de rendement de Mohr-Coulomb et une regle d'ecoulement non associe. Les coefficients de stabilite limite superieure ([[gamma].sub.cr]D/c, oU [[gamma].sub.cr] est le poids unitaire critique; D est la hauteur du tunnel; c est la cohesion) sont deduites pour differentes valeurs d'angles de frottement de coefficients de dilatance [psi]/[phi] ou [psi] est l'angle de dilatation) et de portees sans dimension (B/D, ou B est la portee). Les mecanismes d'effondrement obtenus ne s'etendent pas a la surface du sol et sont principalement composes par une serie de blocs rigides amovibles mutuels. Les valeurs [[gamma].sub.cr]D/c augmentent lorsque les zones d'effondrement diminuent avec une croissante [phi] et [psi]/[phi] et une baisse de B/D. [Traduit par la Redaction] Mots-cles : tunnel enfoui profondement, methode des elements finis a limite superieure, coefficient de stabilite, mecanisme d'effondrement, blocs rigides., Introduction The stability of a single tunnel has attracted considerable attention from scholars. With usage of limit analysis in conjunction with the associated flow rule, stability charts have been established [...]