Cascade catalytic processes perform multi-step chemical transformations without isolating the intermediates. Here, we demonstrate a sequential cascade pathway to convert CO 2 to C 2+ hydrocarbons and oxygenates in a two-step electrocatalytic process using CO as the intermediate. CO 2 to CO conversion is performed by using Ag and further conversion of CO to CC coupled products is performed with Cu. Temporal separation between the two reaction steps is accomplished by situating the Ag electrode upstream of the Cu electrode in a continuous flow reactor. Convection-diffusion simulations and experimental evaluation of the electrodes individually were performed to identify optimal conditions. With the upstream Ag electrode poised at-1 V vs RHE in a flow of CO 2-saturated water in aqueous carbonate buffer, over 80% of the CO can be converted on the downstream Cu electrode. When the Ag electrode is on, a supersaturation of CO is achieved near the Cu electrode, which leads to a relative increase in the formation rate of C 2 and C 3 oxygenates as compared to ethylene.

The ability to perform sophisticated, high-throughput optogenetic experiments has been greatly enhanced by recent open-source illumination devices that allow independent programming of light patterns in single wells of microwell plates. However, there is currently a lack of instrumentation to monitor such experiments in real time, necessitating repeated transfers of the samples to stand-alone instruments and limiting the types of experiments that could be performed. Here we address this gap with the development of the optoPlateReader (oPR), an open-source, solid-state, compact device that allows automated optogenetic stimulation and spectroscopy in each well of a 96-well plate. The oPR integrates an optoPlate optical stimulation module with a module called the optoReader, an array of 96 photodiodes and LEDs that allows 96 parallel light measurements. The oPR was optimized for stimulation with blue light and for measurements of optical density and fluorescence. After calibration of all device components, we used the oPR to measure growth and to induce and measure fluorescent protein expression in E. coli. We further demonstrated how the optical read/write capabilities of the oPR permit computer-in-the-loop feedback control, where the current state of the sample can be used to adjust the optical stimulation parameters of the sample according to pre-defined feedback algorithms. The oPR will thus help realize an untapped potential for optogenetic experiments by enabling automated reading, writing, and feedback in microwell plates through open-source hardware that is accessible, customizable, and inexpensive.

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We present an approach, based on learning an intrinsic data manifold, for the initialization of the internal state values of long short-term memory (LSTM) recurrent neural networks, ensuring consistency with the initial observed input data. Exploiting the generalized synchronization concept, we argue that the converged, “mature” internal states constitute a function on this learned manifold. The dimension of this manifold then dictates the length of observed input time series data required for consistent initialization. We illustrate our approach through a partially observed chemical model system, where initializing the internal LSTM states in this fashion yields visibly improved performance. Finally, we show that learning this data manifold enables the transformation of partially observed dynamics into fully observed ones, facilitating alternative identification paths for nonlinear dynamical systems.