Potassium-chemical synthesis of 3D graphene from CO2 and its excellent performance in HTM-free perovskite solar cells

The conversion of greenhouse gas CO2 into novel materials is the most promising approach to solve greenhouse gas issues. Herein, we report for the first time the reaction of potassium with CO2 to synthesize three-dimensional honeycomb-like structured graphene (3DHG). Furthermore, 3DHG exhibited excellent performance as a counter electrode for hole transport material (HTM)-free perovskite solar cells, leading to a power conversion efficiency of 10.06%. This work constitutes a new aspect of potassium chemistry for material synthesis from a greenhouse gas and the generation of electrical energy from sunlight.Fil: Wei, Wei. Michigan Technological University; Estados UnidosFil: Hu, Baoyun. Tongji University; ChinaFil: Jin, Fangming. Shanghai Jiao Tong University; ChinaFil: Jing, Zhenzi. Tongji University; ChinaFil: Li, Yuexiang. Nanchang University; ChinaFil: Garcia Blanco, Andres Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada ; ArgentinaFil: Stacchiola, Dario Jose. Brookhaven National Laboratory; Estados UnidosFil: Hu, Yun Hang. Michigan Technological University; Estados Unido

The SISAL database: a global resource to document oxygen and carbon isotope records from speleothems

Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide “out-of-sample” evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (δ 18O, δ 13C) measurements are referenced by distance from the top or bottom of the speleothem. Additional tables provide information on dating, including information on the dates used to construct the original age model and sufficient information to assess the quality of each data set and to erect a standardized chronology across different speleothems. The metadata table provides location information, information on the full range of measurements carried out on each speleothem and information on the cave system that is relevant to the interpretation of the records, as well as citations for both publications and archived data. The compiled data are available at https://doi.org/10.17864/1947.147

Feature Fusion Based on Main-Auxiliary Network for Speech Emotion Recognition

Speech emotion recognition is an important research direction of human-computer interaction. Effective feature extraction and fusion are among the key factors to improve the rate of speech emotion recognition. In this paper, a speech emotion recognition algorithm using Main-auxiliary networks for deep feature fusion was proposed. First, segment features are input into BLSTM-attention network as the main network. The attention mechanism can pay attention to the emotion information in speech signals. Then, the Mel spectrum features are input into Convolutional Neural Networks-Global Average Pooling (GAP) as auxiliary network. GAP can reduce the overfitting brought by the fully connected layer. Finally, the two are combined in the form of Main-auxiliary networks to solve the problem of unsatisfactory recognition results caused by direct fusion of different types of features. The experimental results of comparing four models on IEMOCAP dataset show that WA and UA using the depth feature fusion of the Main-Auxiliary network are improved to different degrees

Reduction of CO\u3csub\u3e2\u3c/sub\u3e with H\u3csub\u3e2\u3c/sub\u3eS in a simulated deep-sea hydrothermal vent system

H2S is considered to be an important reductant in abiotic CO2 reduction to organics, however, almost no experimental support has been reported. Herein, the first observation of CO2 reduction to formate with H2S under alkaline hydrothermal conditions is reported, and water is found to act as a hydrogen donor