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The corrosion of glass waste forms for nuclear waste immobilization is a key metric of their performance. Stage III behavior, the delayed acceleration of glass corrosion, remains the aspect of glass corrosion behavior potentially most impactful to long-term performance. Using the addition of various zeolite phases to trigger this effect, the properties of Stage III behavior were evaluated for three high-level waste glass compositions: SRL-202A, SON68, and AFCI. We show that Stage III behavior can occur at temperatures as low as 22 °C, with rate acceleration observed at 90 °C and 70 °C for all studied glasses, and at 40 °C and 22 °C for two of the compositions (SRL-202A and SON68). Using an Arrhenius fit, the activation energy of the process was found to be highly variable, with values between 39 and 68 kJ⋅mol−1. Stage III behavior was triggered for each of the glasses studied by the addition of each of the four zeolites studied (i.e., Na-P1, Na-P2, analcime, and chabazite). The rates of alteration during Stage III varied very little, from 0.0058 to 0.023 g⋅m−2⋅d−1 for the accelerated region immediately following zeolite addition. The acceleration was found to be transient, with the alteration rate decreasing and then accelerating again as the experiments proceeded. The solution composition was evaluated using the strong base/weak acid discriminator developed by Jantzen et al. and it was found that the addition of zeolites can overcome slightly non-optimal solution conditions for zeolite formation to trigger Stage III behavior.

Dialkylmagnesium compounds (MgR2, R = C2H5, C4H9 etc.,) have drawn considerable interest in recent years due to their role in commercial polymerization reactions. Herein, we report a thorough account on the reaction intermediates involved in the synthesis of di-n-butylmagnesium from anhydrous magnesium chloride and n-butyllithium. Energy-dispersive X-ray spectroscopy (EDX) and powder X-ray diffraction (PXRD) were used to characterize the products formed in transmetalation reaction and it supports that the Schlenk equilibrium between the nBuMgCl and nBu2Mg may be operating during the synthesis of di-n-butylmagnesium from anhydrous magnesium chloride. 1,4-Dioxane was used to shift the Schlenk equilibrium to form soluble 1,4-dioxane adduct of di-n-butylmagnesium and insoluble MgCl2 based product. PXRD was used to study the transformation of 1,4-dioxane adduct of di-n-butylmagnesium to pure di-n-butylmagnesium.

Rapid and sensitive detection and quantification of trace and ultra-trace analytes is critical to environmental remediation, analytical chemistry and defense from chemical and biological contaminants. Though affinity based electrochemical sensors have gained immense popularity, they frequently do not meet the requirements of desired sensitivity and detection limits. Here, we demonstrate a complementary luminescence mode that can significantly enhance sensitivity of impedance or voltammetric electrochemical sensors. Our methodology involves using a redox probe, whose luminescence properties change upon changing the oxidation state. By tailoring the system such that these luminescence changes can be correlated with the capture of target analytes, we are able to significantly lower the detection limit and improve the efficiency of detection compared to the electrochemical modes alone. Our proof-of-concept demonstration, using a model system designed for Ca2+ capture, illustrated that the luminescent mode allowed us to lower the limits of detection by three-orders of magnitude compared to the impedance or voltammetric modes alone without requiring any modification of electrode design or cell configuration. Further, the linear ranges of detection are 10−8 to 10−3 M in the voltammetry mode, 10−8 to 10−5 M in the impedance mode and 2.5 × 10−11 to 10−7 M in the luminescent mode, providing a large range of operational flexibility.

Photo-Fenton process is an efficient way to treat the organic pollutants in wastewater. However, the efficiency is limited by serious leaching of iron ions, separation of spent catalyst from reaction system for facile recycling, acidic reaction environment (pH＜4). Herein, a novel double perovskite photocatalyst La2AlFeO6 with high surface area was developed to counter these issues. By altering complexing agents, iron ion content discrepancy and B’-O-B” varies in La2AlFeO6 led to a high surface Fe3+ ratio and an excellent magnetic property. >98.4% of phenol could be degraded in a wide pH range over La2AlFeO6 because of the high surface Fe3+ ratio and promotion of generated ·OH, ·O2– and 1O2. The excellent magnetic property would contribute to separate catalyst from water, and led the used La2AlFeO6 to be reused after simple deionized water rinsing and air drying without any further treatment or calcination.

Organic Rankine cycle (ORC) systems have attracted interest for more than three decades due to advantages in operation at lower working temperature, low maintenance requirements, and relative simplicity (fewer components). In theory, these advantages should make ORC technology more economically attractive for the small and medium power scales (10 kW to 10 MW). Unfortunately, the theoretical promise of ORC systems for power generation has been realized at only a relatively small fraction of the potential market. Although there are a number of reasons for the low utilization of ORC technology, the root cause is directly tied to the relatively low heat-to-power conversion efficiency (2 to 7% typically) and high cost of specially designed expander–generator equipment that is up to 60% of total system cost [1]. The resulting high cost of the power produced just does not make economic sense except in very specialized situations where on-site power is needed but unavailable (at any cost) or where local generation costs are well above regional averages. The overarching objective of the work presented here is to break this paradigm by developing and demonstrating a new harmonic adsorption recuperative power cycle (HARP) system that offers 40% more efficient power generation as compared with a standard ORC system and estimated electric power production costs at very competitive rates below $0.10/kWh.

The rapid, sensitive, and selective detection of target analytes using electrochemical sensors is challenging. ESSENCE, a new Electrochemical Sensor that uses a Shear-Enhanced, flow-through Nanoporous Capacitive Electrode, overcomes current electrochemical sensors' response limitations, selectivity, and sensitivity limitations. ESSENCE is a microfluidic channel packed with transducer material sandwiched by a top and bottom microelectrode. The room-temperature instrument less integration process allows the switch of the transducer materials to make up the porous electrode without modifying the electrode architecture or device protocol. ESSENCE can be used to detect both biomolecules and small molecules by simply changing the packed transducer material. Electron microscopy results confirm the high porosity. In conjunction with the non-planar interdigitated electrode, the packed transducer material results in a flow-through porous electrode. Electron microscopy results confirm the high porosity. The enhanced shear forces and increased convective fluxes disrupt the electric double layer's (EDL) diffusive process in ESSENCE. This disruption migrates the EDL to high MHz frequency allowing the capture signal to be measured at around 100 kHz, significantly improving device timing (rapid detection) with a low signal-to-noise ratio. The device's unique architecture allows us multiple configuration modes for measuring the impedance signal. This allows us to use highly conductive materials like carbon nanotubes. We show that by combining single-walled carbon nanotubes as transducer material with appropriate capture probes, NP-μIDE has high selectivity and sensitivity for DNA (fM sensitivity, selective against non-target DNA), breast cancer biomarker proteins (p53, pg/L sensitivity, selective against non-target HER2).

Gas-consuming electroreduction reactions (GERs), including carbon dioxide reduction reaction, two-electrons oxygen reduction reaction, and nitrogen reduction reaction, are viewed as promising clean and renewable approaches for the sustainable chemicals synthesized from a gas reduction in aqueous mediate, solving the energy and environmental crisis from over-dependent of the fossil fuels. However, due to sluggish kinetics and adsorption linear scaling relations, GERs showcase unfavorable activity, selectivity, and stability, impeding their scale-up application. Over the past few years, tremendous efforts have been made to boost electrocatalyst performance via imposing strain engineering on the linear scaling relations breakup and introducing strain engineered interface to accelerate kinetics. In this review, we summarize the fundamentals and applications of strain engineering-based strategies for boosting electrocatalytic performance in typical GERs. In detailed, the fundamentals of GERs, strain engineering, and linear scaling relations are firstly provided. Furthermore, the impacts of strain engineering on the breaks of linear scaling relations and the corresponding process control mechanism are presented. Moreover, the strain strategies and its application for the individual GERs are highlighted. Additionally, apart from polishing the performance of intrinsic active sites, the progress of gas mass diffusion and charge transfer enhanced by constructing superhydrophobiciltiy/superaerophilicity solid/liquid/gas interfaces, is also needed to be presented. Finally, we discuss guidelines for future opportunities and challenges of strain engineering for boosting electrocatalytic performance. Collectively, we hope that this review will offer a fine control strategy for electrocatalytic performance and clearly illustrate the in-depth mechanism for the catalytic process under the role of strain engineering. Furthermore, many anticipations of such inspirations could extend to synchronized control of multistep elementary competitive reaction in the sustainable production of emerging clean energy and environmental remediation communities.