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We report a strategy to construct a dopamine-releasing gold surface mimicking a presynaptic membrane on a microfluidic chip to simulate in vivo neural signaling. We constructed dopamine self-assembled monolayers (DA SAMs) by electrochemical deprotection of methyl group-protected DA SAMs on a gold surface. Electrochemically controllable release of DA SAMs can be realized by applying nonhydrolytic negative potential on the gold surface. Our method in constructing DA SAMs avoids the polymerization and protonation of DA molecules which may lead to the failure of the DA SAM formation. By combining microfluidics, we realized spatial and temporal controllable release of DA by electrochemistry from the gold surface. Furthermore, by culturing neurons on the patterned DA SAMs, the interface between the DA SAMs and the neurons could serve as a presynaptic membrane, and the spatiotemporal release of DA could modulate the neuron activity with high precision. Our study holds great promise in the fields of neurobiology research and drug screening.

A fungal isolate A-1, identified as Trichoderma citrinoviride by sequencing of the 26S rDNA D1/D2 region, was isolated from the seeds of white Tremella. This fungus was used to degrade the Shanxi lignite. The intensity of the bio-solubilization was determined by measuring the weight loss of the lignite gravimetrically. This fungus solubilized 35% (by weight) of Shanxi lignite after H2O2 pretreatment within 20 days. The enzyme activity analysis showed that the fungus could produce oxidase, lignin peroxidase, and laccase. The degradation mechanism of the fungus was the combined action of multiple extracellular enzymes, which achieved a high degradation efficiency. The lignite and the bio-solubilization products were characterized by ultraviolet spectroscopy (UV), infrared spectroscopy (FT-IR), gas chromatography-mass spectrometry (GC–MS), and X-ray diffraction (XRD). Results showed that the A-1 fungal strain had the abilities of dehydroxylation and demethylation, as well as breaking the side chains of the aromatic rings. After coal degradation, the solid residue mainly contains organic functional groups such as hydroxyl, aromatic ring, and esters, and the liquid product contains aliphatic compounds such as alkanes, alcohols, esters, and phenolic organics. The main characteristic peaks of lignite were quartz (SiO2) and calcite (CaCO3). The relevant characteristic peaks of CaCO3 disappear after the coal sample was pretreated with H2O2, indicating that the pretreatment process relaxed the interaction between coal macromolecules and improved the microbial degradation ability of coal. Trichoderma citrinoviride A-1 can promote biodegradation, and the extracellular enzyme contained in this fungus is the key to the biodegradation mechanism of lignite.

Regional electric power and natural gas systems have become increasingly interdependent in recent years, and have become subject to increasing supply and demand uncertainties associated with renewable energy sources. The present work addresses these issues by developing a multi-stage risk-averse operation model at the level of a regional integrated energy system that considers integrated demand response. Specifically, the developed multi-stage operation model can make flexible wait-and-see decisions, which are adaptive to newly observed uncertainties in the output of renewable energy sources, and the conditional value at risk approach is employed to achieve an economic operating cost at a given risk level. As a result, the multi-stage decision model outperforms conventional two-stage decision models in terms of operating costs. Test results indicate that the operation cost of the multi-stage operation model is reduced by 4.2% compared with a regular two-stage operation model. The impact of congestion in both the electricity and natural gas networks on system operations and energy prices is also investigated.

Based on 837 literatures of CNKI from 2015 to 2020, this paper conducts visualization analysis about domestic fusion of blockchain and supply chain with the utilization of Citespace, and reveal the research hotspots in the field of fusion of blockchain and supply chain in the past five years. The study finds that, firstly, China Finance, Southwest Finance, and Business & Economy are the journals with higher quantity of publication in this field; secondly, Song Hua and Xu Peng are the leading scholars in this research area; thirdly, the research institutions in this field are mainly concentrated in the School of Economics and Management, Law School and School of Information Management in major universities; fourthly, application scenarios, technology development, applied agent and fund are the research hotspots in this area. This study reveals the basic dynamics of domestic fusion of blockchain and supply chain research in the past five years, which not only can promote the theoretical development of this field, but also point out the research hotspots and future research direction for scholars in this area, and provide reference and reference for all walks of life who plans to enter this field.

To ensure the deep-drawability of the deep-drawing sheet, the normal anisotropy and planar isotropy of the sheet is required. The drawing property of the sheet is controlled by its crystallographic texture, the type and orientation density of the texture directly influence the drawing-quality of deep-drawing sheet. {1 1 1}〈1 1 2〉 and {1 1 1}〈1 1 0〉 are the ideal textures for deep-drawing sheet, because the correct texture gives the proper orientation of slip system so that the strength in the thickness direction is greater than that in the plane of the sheet. During the production processing of the deep-drawing sheet, the development of crystallographic texture is continuous, and the final texture character of the product is determined by the texture evolution processing at the different technological process. In the present work, the whole production flow of a coiled sheet has been flowed in Benxi Iron and Steel (Group) Co., Ltd., and the samples were cut from this coiled sheet at the different production flow, such as after hot rolling, cold rolling and recrystallization annealing, respectively. The texture evolution processing has been investigated for the whole production flow of the deep-drawing sheet. Some factors that influence the evolution of the crystallographic texture have been analyzed, such as the grain size of hot-rolled sheet, the reduction ration in the cold rolling, the annealing process, the precipitation of AlN during the coiling and, etc. This paper centers on the research of the texture evolution in each different process. An optimum technique to improve the deep-drawability of the deep-drawing sheet has been put forward.