Naturally Degradable Photonic Devices with Transient Function by Heterostructured Waxy-Sublimating and Water-Soluble Materials

Combined dry–wet transient materials and devices are introduced, which are based on water-dissolvable dye-doped polymers layered onto nonpolar cyclic hydrocarbon sublimating substrates. Light-emitting heterostructures showing amplified spontaneous emission are obtained on transient elements and used as illumination sources for speckle-free, full-field imaging, and transient optical labels are realized that incorporate QR-codes with stably encoded information. The transient behavior is also studied at the microscopic scale, highlighting the real-time evolution of material domains in the sublimating compound. Finally, the exhausted components are fully soluble in water thus being naturally degradable. This technology opens new and versatile routes for environmental sensing, storage conditions monitoring, and organic photonics

Direct Online Environment Monitoring of Water Pollution

Water pollution is one of the most serious ecological threats we face today. Each water body is affected by some organic, inorganic or adioactive pollutant, coming from direct or indirect sources. Surface water and ground water must currently be monitored in all countries on a very large scale by public authorities, but also private companies, to enforce pollution reduction and environmental law compliance. Most of the controls are performed by manually sampling the waters and by sending the samples to an authorized laboratory for the analysis, with high costs, long response times, low sampling frequency and consequent low monitoring data resolution. The research aims to develop methods and to design a device able to perform the sampling, preparation and detecting automatically. The proposed system in fact can be easily installed on site and, once configured and positioned, smart sensors can send analytical data direct ly to the customer with no human intervention. It involves no costs for sampling activities, response times reduced to few minutes and the possibility to achieve high sampling frequency and a consequent strict monitoring of the evolution of the site status. Moreover, the device will be able to collect and share data, according to IoT technology

Basic experimental research on the delineation of the evolutionary process of fault water inrush

Coal mining is seriously threatened by fault water inrush, showing the disaster characteristics of hysteresis and concealment. Mastering the evolution mechanism and process law of fault water inrush disaster has important theoretical guiding significance for carrying out deep water prevention and control work. By constructing water inrush evolution analysis model , the conduction path of confined water and the evolution characteristics of fault zone are analyzed. Using true triaxial rock test system of coupled stress-seepage , combined with acoustic emission and digital speckle technology, large-size rock-like specimens containing fault fracture zone fillings were designed. The instability and failure characteristics of specimens with different lithologic fillings and fault occurrences during biaxial loading were studied. The acoustic emission events and specimen deformation characteristics were obtained. Finally, the modified and upgraded mining floor water inrush simulation test system and parallel electrical on-line monitoring, stress and water pressure monitoring subsystems were used to reproduce the whole process of mining fault water inrush evolution in the laboratory, and the evolution characteristics of monitoring parameters were obtained. The results show that the response of fault zone to mining disturbance is stronger, and it is easier to destroy and destabilize to provide space for confined water conduction. To a certain extent, the nature of fault fillings determines the difficulty of fault activation, then affects the temporal and spatial evolution process of fault water inrush. The fault tip is obviously affected by fluid-solid coupling. The cracks generated by the fault zone and the aquiclude undergo the initiation-expansion-through stage, the relative position relationship between the fault and the working face determines the time and space position of the fault evolution zone and the floor failure zone. According to the conduction path of confined water, the process of fault water inrush is divided into three stages : fault activation, water conduction, double zone (fault evolution zone and floor failure zone) docking, the stage delineation of fault water inrush evolution process are realized

Monitoring of the primary drying of a lyophilization process in vials

An innovative and modular system (LyoMonitor) for monitoring the primary drying of a lyophilization process in vials is illustrated: it integrates some commercial devices (pressure gauges, moisture sensor and mass spectrometer), an innovative balance and a manometric temperature measurement system based on an improved algorithm (DPE) to estimate sublimating interface temperature and position, product temperature profile, heat and mass transfer coefficients. A soft-sensor using a multipoint wireless thermometer can also estimate the previous parameters in a large number of vials. The performances of the previous devices for the determination of the end of the primary drying are compared. Finally, all these sensors can be used for control purposes and for the optimization of the process recipe; the use of DPE in a control loop will be shown as an exampl

Mechanistic modeling of CO2 well leakage in a generic abandoned well through a bridge plug cement-casing gap

Both known and unmapped plugged and abandoned wells are potential leakage pathways for CO2 from geologic carbon sequestration (GCS) sites. Although many abandoned wells have cement bridge plugs installed to prevent leakage, the seal between the cement and the inner casing wall is subject to failure. In this study, we carried out detailed T2Well simulations of cases of sudden non-Darcy flow of CO2 and brine leakage up the gap between a cement plug and the inner steel casing wall that becomes a fully connected flow path during the post-injection period. The goal of our study was two-fold: (1) to understand the dynamics, rates, and the characteristic temporal signals associated with the onset of leakage through various gap-aperture sizes, and (2) to suggest potential monitoring strategies based on the findings. Simulation results show that the leakage of CO2 and brine upward is transient with interesting phase interference behavior. Time-dependent oscillatory flows with varying pressure, temperature, and flow rates of CO2 and brine show strong dependence on gap aperture. Phase-change and decompression lead to very low temperatures at the top of the well for gap apertures larger than 4 mm suggesting that remote thermal monitoring at the ground surface may be an effective way of monitoring even if well locations are not known a priori. Pressure in the well is also indicative of CO2 leakage. The temporal patterns of changing temperature and pressure may be useful diagnostic signals for leakage detection. Finally, these transient leakage signals may provide information on the cause of leakage and/or characteristics of the flow path that could inform effective remediation design and execution approaches

A Review on the Application of Natural Computing in Environmental Informatics

Natural computing offers new opportunities to understand, model and analyze the complexity of the physical and human-created environment. This paper examines the application of natural computing in environmental informatics, by investigating related work in this research field. Various nature-inspired techniques are presented, which have been employed to solve different relevant problems. Advantages and disadvantages of these techniques are discussed, together with analysis of how natural computing is generally used in environmental research.Comment: Proc. of EnviroInfo 201