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This study evaluated the interaction of Chrysanthemum indicum (CI) flavonoids (luteolin, acacetin, and buddleoside) with α‐amylase. Surface plasmon resonance (SPR) assay showed their equilibrium dissociation constants (KD) are 1.9695 ± 0.12, 2.9240 ± 0.20, and 3.2966 ± 0.08 mM at pH 6.0, respectively. Furthermore, their binding affinities were influenced by KCl, MgCl2, and CaCl2. Enzymatic kinetic studies revealed that three flavonoids exhibited noncompetitive α‐amylase inhibitory activity. The inhibitory sequence is luteolin > acacetin > buddleoside, which was in accordance with the results of binding affinity from SPR. 1,1‐diphenyl‐2‐picryl hydrazyl radical assay demonstrated that antioxidant activities of three flavonoids were inhibited significantly with α‐amylase. Meanwhile, the study reveals that hydroxyl on C′‐4, C′‐5, and C‐7 of flavonoids play an important role on the interaction of three flavonoids with α‐amylase. Also, SPR could be used as sensor for rapid screening inhibitors of α‐amylase and provide useful information for the application of C. indicum flavonoids in food and pharmaceutical area. [ABSTRACT FROM AUTHOR]

Summary: In this work, the effects of three Citrus flavonoids (naringin, neohesperidin and hesperidin) on α‐amylase catalysed starch digestion were investigated. An inhibitory kinetics experiment demonstrated that they noncompetitively inhibit the activity of α‐amylase with Ki values of, respectively, 25.21 μ m, 40.26 μ m, 40.69 μ m. Surface plasmon resonance assay showed three Citrus flavonoids can bind with starch with KD values of, respectively, 3.98 ± 0.20 m m, 4.92 ± 0.15 m m and 5.07 ± 0.17 m m. Scanning electron microscopy indicated they can delay the retrogradation of starch. The results of 1, 1‐diphenyl‐2‐picryl hydrazyl radical assay indicate that the antioxidant activities of three Citrus flavonoids are significantly decreased by interacting with starch. These results illustrated three Citrus flavonoids that retard the digestion of starch not only through interaction with α‐amylase, but also through interaction with starch. [ABSTRACT FROM AUTHOR]

Aiming at the problem of the analysis and optimization on the hydraulic excavator attachments' digging force, the research about the relationship of the key hinge points' location and the largest digging force was put forward. A co-simulation method of the dynamics of mechanical systems and hydraulic systems was introduced to establish the attachments virtual prototype model. On the condition of that the bucket and boom cylinder were locked and the stick cylinder pressure was closed to the largest system preesure, the digging force diagram within the working range was analyzed and the maximum stick digging force was also concluded. On this basis, the maximum digging force was selected to the design goal, through experimental design and Monte Carlo methods, the influence of the key hinge points' spatial location to the maximum stick digging force were studied. The results indicate that the hydraulic excavator digging force is close to similar foreign products, and at the same time, the location and value of the stick digging force are find out which provide a valid basis for the optimization design and structural strength analysis of attachments. [ABSTRACT FROM AUTHOR]

Nitrogen Doped Intercalation TiO 2 /TiN/Ti 3 C 2 T x Nanocomposite Electrodes with Enhanced Pseudocapacitance. Reference 1 Yang B., She Y., Zhang C., Kang S., Zhou J., Hu W. Nitrogen Doped Intercalation TiO2/TiN/Ti3C2Tx Nanocomposite Electrodes with Enhanced Pseudocapacitance. In the investigation of the cycle performance of the electrode, the last five galvanostatic charge-discharge (GCD) curves in the inset of Figure 10a and the corresponding Nyquist impedance spectra in Figure 10b were not updated. [Extracted from the article]

Layered two-dimensional titanium carbide (Ti 3 C 2 T x ), as an outstanding MXene member, has captured increasing attention in supercapacitor applications due to its excellent chemical and physical properties. However, the low gravimetric capacitance of Ti 3 C 2 T x restricts its rapid development in such applications. Herein, this work demonstrates an effective and facile hydrothermal approach to synthesize nitrogen doped intercalation TiO 2 /TiN/Ti 3 C 2 T x with greatly improved gravimetric capacitance and excellent cycling stability. The hexamethylenetetramine (C 6 H 12 N 4 ) in hydrothermal environment acted as the nitrogen source and intercalants, while the Ti 3 C 2 T x itself was the titanium source of TiO 2 and TiN. We tested the optimized nitrogen doped intercalation TiO 2 /TiN/Ti 3 C 2 T x electrodes in H 2 SO 4 , Li 2 SO 4 , Na 2 SO 4 , LiOH and KOH electrolytes, respectively. The electrode in H 2 SO 4 electrolyte delivered the best electrochemical performance with high gravimetric capacitance of 361 F g -1 at 1 A g -1 and excellent cycling stability of 85.8% after 10,000 charge/discharge cycles. A systematic study of material characterization combined with the electrochemical performances disclosed that TiO 2 /TiN nanoparticles, the introduction of nitrogen and the NH 4 + intercalation efficaciously increased the specific surface areas, which is beneficial for facilitating electrolyte ions transportation. Given the excellent performance, nitrogen doped intercalation TiO 2 /TiN/Ti 3 C 2 T x bodes well as a promising pseudocapacitor electrode for energy storage applications.

The development of organic-inorganic hybrid perovskite materials has been rapid in recent years; but their applications are limited by the toxicity and stability of the materials. To address these issues in the context of resistive switching devices, an inorganic lead-free perovskite namely CsBi 3 I 10 is developed. Uniform and pinhole-free CsBi 3 I 10 thin films can be fabricated by using CsI-rich precursor solution via a facile antisolvent-assisted spin-coating method. The nonvolatile resistive switching devices based on CsBi 3 I 10 demonstrate a large on/off ratio (10 3 ), reliable retention properties (10 4 s), and endurance (150 cycles). Conductive atomic force microscopy reveals that the high- and low-resistance states are formed by breaking and formation of conductive filaments in the perovskite thin film. Because of the excellent stability of the CsBi 3 I 10 perovskite, the devices exhibit no obvious change in resistive switching behavior even after over 2 month storage in an ambient (60% relative humidity) environment. Our work suggests that the all-inorganic lead-free CsBi 3 I 10 perovskite has great potential in resistive switching memory as well as in other optoelectronic devices where toxicity and stability are a concern.