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Three new triterpenoid glycosides, 2α,3α,23,24-tetrahydroxyurs-12,19- dien-oic acid 28-O-β- D -glucopyranoside (1), 2α,3β,23,24-tetrahydroxyurs-12, 19(29) -dien-28-oic acid 28-O-β- D -glucopyranoside (2), and 2α,3β,23,24-tetrahydroxyurs-12, 18-dien-28-oic acid 28-O-β- D -glucopyranoside (3) were isolated from Aronia melanocarpa (Michx.) Elliott. Their structures were elucidated by extensive spectroscopic methods. All the isolated compounds displayed moderate inhibitory activity against nitric oxide production in macrophages. [ABSTRACT FROM AUTHOR]

Three new compounds, arneatas A-C (1–3), together with three known compounds (4–6) were isolated from the roots of Arnebia guttata Bunge. The structures were established on the basis of extensive spectroscopic data including NMR and HRESIMS. All the new compounds (1–3) were tested for their cytotoxic activity against two glioma cell lines (U118-MG and U373-MG) in vitro after treatment for 48 h. Compound 1 exhibited moderate cytotoxic activity against U118-MG and U373-MG glioma cell lines, with IC50 values of 10.4 and 17.5 µM, respectively. [ABSTRACT FROM AUTHOR]

The meticulous design of heterogeneous interfaces presents a promising approach for enhancing the electrocatalytic activity of Cu-based materials in nitrate reduction reactions. Herein, we developed a self-templated metal–organic frameworks transformation strategy to synthesize hollow multi-metallic oxide materials with well-defined interfaces. By utilizing novel hollow Cu–Co bimetallic Prussian blue analogs as precursors, a hollow cage composed of ultra-small CuO/Co3O4 hetero-nanograins was successfully constructed. It was discovered that this structure greatly enhanced the electrocatalytic activity for the conversion of NO3− to NH3, achieving a remarkably high Faradaic efficiency (FE) for NH3 (with a maximum FE of 90.68%) at low overpotential ranges. Furthermore, electrochemical experiments and in situ spectroscopy provided evidence that electrochemically induced reconstruction led to the formation of synergistic sites between Cu and Co3O4. This enabled the sequential reduction of nitrate and nitrite on adjacent metal/metal oxide phases, resulting in the rapid generation of NH3.Graphical Abstract: The meticulous design of heterogeneous interfaces presents a promising approach for enhancing the electrocatalytic activity of Cu-based materials in nitrate reduction reactions. Herein, we developed a self-templated metal–organic frameworks transformation strategy to synthesize hollow multi-metallic oxide materials with well-defined interfaces. By utilizing novel hollow Cu–Co bimetallic Prussian blue analogs as precursors, a hollow cage composed of ultra-small CuO/Co3O4 hetero-nanograins was successfully constructed. It was discovered that this structure greatly enhanced the electrocatalytic activity for the conversion of NO3− to NH3, achieving a remarkably high Faradaic efficiency (FE) for NH3 (with a maximum FE of 90.68%) at low overpotential ranges. Furthermore, electrochemical experiments and in situ spectroscopy provided evidence that electrochemically induced reconstruction led to the formation of synergistic sites between Cu and Co3O4. This enabled the sequential reduction of nitrate and nitrite on adjacent metal/metal oxide phases, resulting in the rapid generation of NH3. [ABSTRACT FROM AUTHOR]

With the rapid development of Internet of things and big data technology, the amount of data collected by SCADA(Supervisory Control And Data Acquisition)system is growing exponentially, which the traditional SDT algorithm can not meet the requirements of SCADA system for historical data compression. In this paper, ASDT(Advanced SDT) algorithm based on SDT algorithm is proposed and implemented in the Java language, which is based on the deep research of the data compression method, especially the Swing Door Trending. ASDT algorithm through the sine curve fitting data to achieve data compression, compared with the performance of the traditional SDT algorithm, which it can achieve better compression results. The experimental results show that compared with the traditional SDT algorithm, the ASDT algorithm can improve the compression ratio in the case of no significant increase in the compression error, and the compression radio is increased by nearly 50%.

Tuning metal–support interactions (MSIs) to precisely control the selectivity of supported Cu catalysts toward the CO2 reduction reaction (CO2RR) is a crucial yet challenging topic. Herein, a series of CuO nanosheet/CeO2 nanorod composites with various morphologies and compositions were synthesized and used as electrocatalysts. The CO2RR product distributions of composites are experimentally verified to be dependent on the loading amounts and sizes of CuO nanosheets, with the maximum Faradaic efficiency (FE) of CH4 and C2H4 reaching 37.8 and 44.8%, respectively. The mechanism investigation supports our perspective that modulating the strength of the MSIs between CuO nanosheets and CeO2 nanorods not only influences the adsorption properties of CO2RR intermediates but also further dominates the formation of exposed facets during the CuO structural reconstruction process, thus customizing the CO2RR pathway. [ABSTRACT FROM AUTHOR]

To improve the sensitivity for electro-chemiluminescent (ECL) detection of chloramphenicol (CAP), a common broad-spectrum antibiotic, boron nitride quantum dots (BNQDs) were prepared with excellent photoelectric property and low toxicity. After its structure and electrochemical property were investigated in detail, it was noted that the ECL signal of Ru(Phen)32+ could be strengthened by the proposed BNQDs, which was further activated by ten’s times in the presence of CAP. Under the optimized conditions, there was an excellent linear relationship between Î"ECL and lg c CAP in a wide linear range from 1.0 × 10âˆ'10 to 1.0 × 10âˆ'6 mol lâˆ'1 CAP. The detection limit was super-low to be 3.3 × 10âˆ'11 mol lâˆ'1 (S/N = 3). When applied for CAP detection in real pharmaceutical and food samples, the recoveries were between 97.8% and 105.7% with R.S.D. less than 3.3%. A possible CAP-activated ECL mechanism of BNQDs-Ru(phen)32+ was also proposed. This work will offer a great potential for efficient monitoring of CAP pollution and clinical diagnosing of CAP-related diseases in future. [ABSTRACT FROM AUTHOR]