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Mixed‐halide perovskites can undergo a photoinduced phase segregation. Even though many reports have claimed that such a phase segregation process is reversible, what happens after phase segregation and its impact on the performance of perovskite‐based devices are still open questions. Here, the phase transformation of MAPb(I1−xBrx)3 after phase segregation and probe an irreversible phase reconstruction of MAPbBr3 is investigated. The photoluminescence imaging microscopy technique is introduced to in situ record the whole process. It is proposed that the type‐I band alignment of segregated I‐rich and Br‐rich domains can enhance the emission of the I‐rich domains by suppressing the nonradiative recombination channels. At the same time, the charge injection from Br‐rich to I‐rich domains drives the expulsion of iodide from the lattice, and thus triggers the reconstruction of MAPbBr3. The work highlights the significance of ion movements in mixed‐halide perovskites and provides new perspectives to understand the property evolution. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal dichalcogenide (TMD) has emerged as an effective optoelectronics material due to its novel optical properties. Understanding the role of defects in exciton kinetics is crucial for achieving high-efficiency TMD devices. Here, we observe defects induced anomalous power dependence exciton dynamics and spatial distribution in hexagonal heterogeneous WS2. With transient absorption microscopy study, we illustrate that these phenomena originate from the competition between radiative and defect-related non-radiative decays. To understand the physics behind this, a decay model is introduced with two defect-related channels, which demonstrates that more excitons decay through non-radiative channels in the dark region than the bright region. Our work reveals the mechanisms of anomalous exciton kinetics by defects and is instrumental for understanding and exploiting excitonic states in emerging 2D semiconductors. [ABSTRACT FROM AUTHOR]

Solvent-based post-combustion capture technologies have great potential for CO2 mitigation in traditional coal-fired power plants. Modelling and simulation provide a low-cost opportunity to evaluate performances and guide flexible operation. Composed by a series of partial differential equations, first-principle post-combustion capture models are computationally expensive, which limits their use in real time process simulation and control. In this study, we propose a first-principle approach to develop the basic structure of a reduced-order model and then the dominant factor is used to fit properties and simplify the chemical and physical process, based on which a universal and hybrid post-combustion capture model is established. Model output at steady state and trend at dynamic state are validated using experimental data obtained from the literature. Then, impacts of liquid-to-gas ratio, reboiler power, desorber pressure, tower height and their combination on the absorption and desorption effects are analyzed. Results indicate that tower height should be designed in conjunction with the flue gas flow, and the gas-liquid ratio can be optimized to reduce the reboiler power under a certain capture target. [ABSTRACT FROM AUTHOR]

Long‐term stability has become the major obstacle for the successful large‐scale application of perovskites devices. Owing to the ionic nature of metal‐halide perovskites, the interfacial ion diffusion can induce irreversible degradation under operational conditions, which presents a great challenge to realize stable perovskite solar modules. Here, a diphenylphosphine oxide compound, ethane‐1,2‐diylbis(diphenylphosphine oxide) (DPPO) is introduced to coordinate with lead iodide and form a cross‐linked 1D Pb3I6‐DPPO (1D‐PbI2) complex. These judiciously designed cross‐linked nonionic low‐dimensional lead halide/organic adducts can passivate the defects of perovskite while acting as a robust ion diffusion barrier, thus significantly improving the electronic quality and intrinsic stability of perovskite films. As a result, high‐performance inverted (p‐i‐n) solar modules with a champion efficiency approaching 19% (a certified stabilized efficiency of 17.8%) for active device areas above 17 cm2 without the use of antisolvents, accompanied by outstanding operational stability under heat stress and continuous illumination are achieved. [ABSTRACT FROM AUTHOR]

The brain-derived neurotrophic factor (BDNF) stimulates long-term potentiation induced by theta-burst (LTP(sub T)) by increasing the capability of the hippocampal synapses to respond to high-frequency stimulations. Hippocampal slices from postnatal day 12-13 are unable to respond to tetanic stimulation in the absence of BDNF. In the presence of BDNF, the slices show LTP(sub T). A TrkB-IgG fusion protein that removes BDNF suppresses synaptic responses to tetanus and LTP(sub T) level.

The Xenopus frequenin (Xfreq), a Ca2+ -binding protein, increases transmitter release at the neuromuscular synapses by increasing the synaptic efficacy of spinal neurons. Its expression during development corresponds to the maturation of the neuromuscular synapses. This protein is 70% identical to the frequenin of Drosophila and contains four EF-hands and Ca2+ binding motifs. Its concentration in the brain is high but is insignificant in muscles.

Nitric oxide (NO) acts as a retrograde signal in the activity-dependent synaptic inhibition at neuromuscular synapses. Spontaneous and invoked synaptic currents are blocked by NO donors and activators of the cyclic GMP channel. NO released from a postsynaptic myocyte induces synaptic suppression. The NO-binding protein hemoglobin and NO synthase inhibitors avert the synaptic suppression triggered by postsynpatic depolarization.

Neurotrophin 3 (NT-3) is implicated in the promotion of neuronal activity and a related regulation of synaptic transduction in cortical neurons. The rate of spontaneous action potentials is increased and excitatory synaptic activities in growing cortical neurons are regulated by NT-3. NT-3 suppresses gamma-aminobutyric acid (GABA) subtype A receptor-mediated inhibitory synaptic transduction. Hence lowering GABAergic transduction is responsible for the excitatory effects of NT-3 on spontaneous action potentials.