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Porphyrin metal–organic framework PMOF-2 with a 3D pillar-layered framework showed a better third-order NLO performance than PMOF-1 with a 2D bilayer, revealing the influence of dimensions on third-order nonlinear properties of MOFs.

A Cu4Ti4-oxo cluster stabilized by in situ – formed 2,2′-biphenolate ligands from the oxidative coupling of phenols was obtained, showing short Cu⋯C contacts.

A facile “chemical scissor” strategy is first proposed to rationally design a dangling bond for COF materials, which remarkably promotes their gas sensing performance.

A series of catecholate-functionalized titanium-oxo clusters (TOCs)

The integration of Ti4L6 (L = embonate) cages and various N,N-chelated transition-metal cations into tightly packed structures accurately leads to high-performance materials with adjustable nonlinear optical (NLO) effects.

Mixed X-anion perovskites, such as CsPbX3 (X = Cl, Br, or I), play an important role in photovoltaic applications.

Flexible metal-organic frameworks (MOFs) are one kind of stimuli-responsive materials that exhibit reversible structural transformations in response to external stimuli. Exploring and understanding the stimuli response behavior of flexible MOFs is challenging, as it involves weak host-guest interaction. We report here the unique flexibility of MOF Zn(int)(Ad) (TIF-A1, Hint = isonicotinic acid, Had = adenine) induced by acetylene adsorption. TIF-A1 is rigid toward most gas molecules, while only C

Renal Inflammatory myofibroblastic tumor (IMT) is very rare and lacks characteristic clinical manifestation and radiographic features. This is a case discussing the radiologic and pathologic findings of a renal IMT in a 6-year-old boy who underwent radical nephrectomy for a right renal mass that was misdiagnosed as Wilms’ tumor.

As one of the most representative polyoxometalate (POM) structures, Keggin clusters have attracted considerable attention. Nevertheless, the noble-metal-templated Keggin structure has not been reported to date. In this work, for the first time, a Ag atom was successfully incorporated to template the formation of a γ-Keggin alkytin-oxo cluster. Moreover, the central Ag atom has brought a significant heavy atom effect, showing the important influence on the electronic structure and optical properties. Theoretical calculations demonstrate that the Ag atom affects the frontier molecular orbitals and excited states of the AgSn

Perturbing the periodic electronic structure of the MoS2 basal plane via vacancy engineering offers an opportunity to explore its intrinsic activity. A significant challenge is the design of vacancy states, which include its type, distribution, and accessibility. Here, well-dispersed and vertically aligned MoS2 nanosheets with an in-plane selectively cleaved Mo-S bond on a carbon matrix (c-MoS2-C) have been prepared by a self-engaged strategy, which synergistically realizes uniform vacancy manufacturing and three-dimensional (3D) self-assembly of the defective MoS2 nanosheets. X-ray adsorption spectroscopy investigation confirms that the cleaved MoS2 basal plane generates newly active edge sites, where the Mo centers feature unsaturated coordination geometry. Theoretical calculations reveal that the exposed interior edge Mo sites represent new active centers for hydrogen adsorption/desorption. As expected, the synthesized c-MoS2-C exhibits markedly enhanced hydrogen evolution activity and superior stability. This in-plane activation strategy could be extended to other types of transition-metal dichalcogenides and catalytic reaction systems.

Kiwifruit (Actinidia chinensis) is a nutrient-dense fruit abundant in vitamin C and phenolic compounds, and it exhibits strong antioxidant capacity. However, the antioxidants in ‘Jinfeng’ kiwifruit have seldom been extracted and analyzed, and the conditions for the extraction of kiwifruit antioxidants by ultrasound-assisted extraction (UAE) have seldom been investigated. In this study, response surface methodology (RSM) was used to optimize UAE conditions to extract antioxidants from ‘Jinfeng’ kiwifruit. In addition, the antioxidant capacity, contents of total phenolics and total flavonoids, ascorbic acid, and the profiles of antioxidants were also analyzed. The results showed that the optimal UAE conditions included 68% ethanol, liquid/solid ratio at 20 mL/g, extraction time at 30 min, extraction temperature at 42 °C, and ultrasonic power at 420 W. Under these conditions, the ABTS value of kiwifruit was 70.38 ± 1.38 μM TE/g DW, which was 18.5% higher than that of the extract obtained by conventional solvent extraction. The total phenolic and flavonoid contents were 15.50 ± 0.08 mg GAE/g DW and 5.10 ± 0.09 mg CE/g DW, respectively. Moreover, 20 compounds were tentatively identified by UPLC–MS/MS, and the content of main compounds, such as procyanidin B2, neochlorogenic acid, and epicatechin, were determined by HPLC–DAD. This research revealed the profiles of antioxidant phytochemicals in ‘Jinfeng’ kiwifruit, which can be a good dietary source of natural antioxidants with potential health functions.

Inspired by the recent practical application of two-dimensional (2D) nanomaterials as gas sensors, catalysts, and materials for waste gas disposal, herein, the adsorption behaviors of environmental gas molecules, including NO, CO, O

Developing efficient oxygen evolution reaction (OER) electrocatalysts is important for enhancing the water splitting efficiency. However, with the current catalysts containing one kind of active sites, it is challenging to achieve low overpotentials because of the four-electron transfer process. Herein is reported HZIF-2-CoMo, a new metal-organic framework with well-defined Co-Mo dual sites that can promote the OER process through an unconventional Mo6+/Co2+ dual-site relay mechanism. Theoretical calculations suggested that the Mo and Co sites stabilize the HO* and HOO* intermediates, respectively, and that the unique Co-O-Mo configuration induces the formation of a Co-O*-Mo transition intermediate, remarkably reducing the reaction free energy. As a result, HZIF-2-CoMo shows an overpotential of 277 mV at 10 mA cm-2 and a low Tafel slope of 70 mV dec-1 in alkaline solution, making it one of the best OER electrocatalysts reported to date.

Perturbing the periodic electronic structure of the MoS

The hydrolysis of earth-abundant Al

Ultrathin 2D materials possess unique properties that translate to enhanced efficiency as electrocatalysts, stimulating research toward methodologies that support their preparation. Herein, a two-step strategy is reported that involves the preparation of the new boron imidazolate framework (BIF-73) which is subsequently utilized as a precursor to yield the crystalline 2D nanosheet material (Fe@BIF-73-NS) via post-synthetic modification. This new electrocatalytic material stabilizes ultra-small (Fe2 O3 ) fragments resulting in an excellent electrocatalytic performance for the oxygen evolution reaction (OER: lower overpotential with 291 mV at the current density of 10 mA cm-2 ) and carbon dioxide reduction reaction (faradaic efficiency of CO reaching 88.6% at -1.8 V vs Ag/AgCl) without the need for noble metals. Additionally, theoretical calculations and microscopy reveal that the superior OER performance can be attributed to the increased exposure of binding sites within the material to which the catalytically active Fe3+ centers are bound through a post-synthetic modification procedure. A red-shift of the Fermi level around the valence band is observed and is proposed to be a result of the aforementioned interactions. This work opens an avenue toward the development of 2D functional metal organic framework nanosheets for energy conversion applications.

The emergence of Mo-based hybrid zeolitic imidazolate frameworks (HZIFs) with MoO4 units brings substantial advantages to design and synthesize complex Mo-based electrocatalyst that are not expected in their conventional synthesis path. Herein, as a newly proposed concept, a facile temperature-induced on-site conversion approach (TOCA) is developed to realize the transformation of MoO4 units to C-Mo-S triatomic coordination in hierarchical hollow architecture. The optimized hybrid (denoted as MoCSx 1000) shows accelerating oxygen reduction reaction (ORR) kinetics and excellent stability, which are superior to the most reported Mo-based catalysts. Extended X-ray adsorption fine structure (EXAFS) analysis and computational studies reveal that the near-range electronic steering at C-Mo-S triatomic-coordinated nanointerface guarantees moderate ORR intermediates adsorption and thus is responsible for the boosted ORR activity. This work sheds light on exploring the intrinsic activity of catalysts by interfacial electronic steering.

The speed regulating system of DC blushless motor was mostly studied. This paper is based on a simplified mathematical model of Brushless DC motor which was consisted of the traditional PID and single neurons. In the Simulink environment, it is established by the control algorithm of single neuron adaptive PID brushless DC motor speed control system closed loop simulation model. From simulation results, the single neuron adaptive PID control system of DC brushless motor has excellent dynamic and static performance. Based on the analysis of DC blushless motor speed control system and simulation results of the neural network control algorithm, hardware of the digital control system for DC brushless motor is designed with control center of high performance microcontroller 80C196KC,which is of single neuron adaptive PID control algorithm.