In this paper, a Ni and diamond-like carbon (DLC)-modified TiO2 nanotube composite electrode was prepared as a glucose sensor using a combination of an anodizing process, electrodeposition, and ...magnetron sputtering. The composition and morphology of the electrodes were analyzed by a scanning electron microscope and energy dispersive X-ray detector, and the electrochemical glucose oxidation performance of the electrodes was evaluated by cyclic voltammetry and chronoamperometry. The results show that the Ni-coated DLC-modified TiO2 electrode has better electrocatalytic oxidation performance for glucose than pure TiO2 and electrodeposited Ni on a TiO2 electrode, which can be attributed to the synergistic effect between Ni and carbon. The glucose test results indicate a good linear correlation in a glucose concentration range of 0.99–22.97 mM, with a sensitivity of 1063.78 μA·mM−1·cm−2 and a detection limit of 0.53 μM. The results suggest that the obtained Ni-DLC/TiO2 electrode has great application potential in the field of non-enzymatic glucose sensors.
Water electrolysis shows great promise for the low-cost mass production of high-purity hydrogen. The relatively high dissociation energy of water, however, often results in rather sluggish kinetics ...of the hydrogen evolution reaction (HER) in alkaline conditions, even for the case of state-of-the-art Pt-based electrocatalysts. Here, we show the high efficiency of the hybrids of PtRu nanoclusters (NCs) and black phosphorus (BP) nanosheets in HER. Our PtRu NCs/BP electrocatalysts demonstrate a HER activity of 88.5 mA cm–2 at −70 mV in 1 M KOH, which is higher than that of commercial Pt/C by 1 order of magnitude. The observed extraordinarily high HER activity of the PtRu NCs/BP hybrids is interpreted in the framework of density functional theory. Theoretical modeling indicates that the electronic interaction between BP and PtRu NCs speeds up the dissociation of water and optimizes the adsorption strength for H* species, giving rise to the remarkably high HER activity of the PtRu NCs/BP hybrids.
The emergence of superconductivity in doped insulators such as cuprates and pnictides coincides with their doping‐driven insulator–metal transitions. Above the critical doping threshold, a metallic ...state sets in at high temperatures, while superconductivity sets in at low temperatures. An unanswered question is whether the formation of Cooper pairsin a well‐established metal will inevitably transform the host material into a superconductor, as manifested by a resistance drop. Here, this question is addressed by investigating the electrical transport in nanoscale rings (full loops) and half loops manufactured from heavily boron‐doped diamond. It is shown that in contrast to the diamond half‐loops (DHLs) exhibiting a metal–superconductor transition, the diamond nanorings (DNRs) demonstrate a sharp resistance increase up to 430% and a giant negative “magnetoresistance” below the superconducting transition temperature of the starting material. The finding of the unconventional giant negative “magnetoresistance”, as distinct from existing categories of magnetoresistance, that is, the conventional giant magnetoresistance in magnetic multilayers, the colossal magnetoresistance in perovskites, and the geometric magnetoresistance in semiconductor–metal hybrids, reveals the transformation of the DNRs from metals to bosonic semiconductors upon the formation of Cooper pairs. DNRs like these could be used to manipulate Cooper pairs in superconducting quantum devices.
Nanoscale “diamond rings” provide unconventional giant “magnetoresistance” for the development of new quantum devices. The unconventional giant “magnetoresistance” caused by the trapping of Cooper pairs within the heavily boron‐doped diamond nanorings, distinguishes itself from the conventional giant magnetoresistance originating from spin‐dependent scattering of single electrons in layered magnetic materials.
Due to the wide use of iron in all kinds of areas, the design and construction of direct, fast, and highly sensitive sensor for Fe
3+
are highly desirable and important. In the present work, a kind ...of fluorescent MXene quantum dots (MQDs) was synthesized via an intermittent ultrasound process using
N,N
-dimethyl formamide as solvent. The prepared MQDs were characterized via a combination of UV–Vis absorption, fluorescence spectra, X-ray photoelectron energy spectra, and Fourier-transform infrared spectroscopy. Based on the electrostatic-induced aggregation quenching mechanism, the fluorescent MQDs probes exhibited excellent sensing performance for the detection of Fe
3+
, with a sensitivity of 0.6377 mM
−1
and the detection limit of 1.4 μM, superior to those reported in studies. The present MQDs-based probes demonstrate the potential promising applications as the sensing device of Fe
3+
.
Atomic layer deposition (ALD) is a vapor phase technique capable of producing a variety of materials. It consists of the alternation of separate self-limiting surface reactions, which enables ...accurate control of film thickness at the Angstrom level. ALD becomes a powerful tool for a lot of industrial and research applications. Coating strategies are the key for ALD; however, there are few systematic reviews concerning coating strategies for ALD. This review provides a detailed summary of state-of-the-art coating strategies in ALD, emphasizing the recent progress in the fabrication of novel nanostructures. The progress in coating strategies is reviewed in three parts: template-assisted preparation of low-dimensional nanomaterials and complex nanostructures; surface treatments, including the surface activation and the surface blocking ways; enhanced reactor, such as plasma and fluid bed reactor, and improved growth method such as the ABC-type model. In addition, we also discussed the challenges facing the coating method for ALD.
In China, warfarin is usually prescribed with Chuanxiong Rhizoma for treating thromboembolism diseases. However, the reason for their combination is still being determined. The present study explored ...the pharmacokinetics interactions of warfarin, Chuanxiong Rhizoma, and gut microbiota in the rat model of middle cerebral artery occlusion (MCAO).
A total of 48 rats were randomly divided into six groups: MCAO rats orally administered warfarin (W group), pseudo germ-free MCAO rats orally administered warfarin (W-f group), MCAO rats co-administered Chuanxiong Rhizoma and warfarin (C + W group), pseudo germ-free MCAO rats co-administered Chuanxiong Rhizoma and warfarin (C + W-f group), MCAO rats co-administered warfarin and senkyunolide I (S + W group); pseudo germ-free MCAO rats co-administered warfarin and senkyunolide I (S + W-f group). After treatment, all animals' blood and stool samples were collected at different time points. The stool samples were used for 16S rRNA sequencing analysis. Ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) method was established to quantify warfarin, internal standards, and the main bioactive components of Chuanxiong in blood samples. The main pharmacokinetics parameters of warfarin were calculated by DAS 2.1.1 software.
The relative abundance of
and
in the pseudo germ-free groups (W-f, C + W-f, S + W-f) was lower than that in the other three groups (W, C + W, S + W). The relative abundance of
in the W-f group was higher than that of the W group, while the relative abundance of
decreased. The relative abundance of Ruminococcaceae
and Ruminococcaceae
in the S + W-f group was lower than in the S + W group. Compared to the W group, the AUC
and C
of warfarin in the W-f group increased significantly to 51.26% and 34.58%, respectively. The AUC
and C
in the C + W group promoted 71.20% and 65.75% more than the W group. Compared to the W group, the AUC
and C
increased to 64.98% and 64.39% in the S + W group.
Chuanxiong Rhizoma and senkyunolide I (the most abundant metabolites of Chuanxiong Rhizoma aqueous extract) might affect the pharmacokinetics features of warfarin in MCAO rats through, at least partly, gut microbiota.
The structures of small cationic silver clusters Ag
(n = 3-13) are investigated by comparing measured far-infrared multiple photon dissociation spectra of cluster-argon complexes with the calculated ...harmonic vibrational spectra of different low-energy structural isomers. A global structure search was carried out using the CALYPSO structure prediction method, after which isomers were locally optimized with the meta GGA functional TPSS. The obtained structures of the cationic silver clusters are mostly consistent with earlier ion mobility measurements and photodissociation spectroscopy studies for Ag
(n = 3-11) and allowed excluding several structural isomers that were considered in those earlier studies, which illustrates the strength of combining multiple experimental techniques for conclusive structural identification. The growth pattern of the cationic silver clusters is discussed and differences with other cationic coinage metal clusters are highlighted.
Population pharmacokinetic (PopPK) models of posaconazole have been established to promote the precision dosing. However, the performance of these models extrapolated to other centers has not been ...evaluated. This study aimed to conduct an external evaluation of published posaconazole PopPK models to evaluate their predictive performance. Posaconazole PopPK models screened from the PubMed and MEDLINE databases were evaluated using an external dataset of 213 trough concentration samples collected from 97 patients. Their predictive performance was evaluated by prediction-based diagnosis (prediction error), simulation-based diagnosis (visual predictive check), and Bayesian forecasting. In addition, external cohorts with and without proton pump inhibitor were used to evaluate the models respectively. Ten models suitable for the external dataset were finally included into the study. In prediction-based diagnostics, none of the models met pre-determined criteria for predictive indexes. Only M4, M6, and M10 demonstrated favorable simulations in visual predictive check. The prediction performance of M5, M7, M8, and M9 evaluated using the cohort without proton pump inhibitor showed a significant improvement compared to that evaluated using the whole cohort. Consistent with our expectations, Bayesian forecasting significantly improved the predictive per-formance of the models with two or three prior observations. In general, the applicability of these published posaconazole PopPK models extrapolated to our center was unsatisfactory. Prospective studies combined with therapeutic drug monitoring are needed to establish a PopPK model for posaconazole in the Chinese population to promote individualized dosing.
The geometric structures of Si n Au+ (n = 2–11, 14, and 15) clusters are investigated using density functional theory computations in combination with infrared multiple-photon dissociation spectra ...measured on the corresponding cluster·argon and cluster·xenon complexes. The Si n Au+ clusters adopt planar structures for the smallest sizes (n = 2–4) and have three-dimensional geometries for larger sizes (n ≥ 5). All of the investigated Si n Au+ clusters have exohedral structures in which the Au dopant atom is adsorbed on a surface site of the bare Si n + cluster at a low-coordinated position. The growth mechanism of Si n Au+ clusters is discussed and compared with those of Si n Cu+ and Si n Ag+. The present results indicate that the filled d shell and the atomic radii of the dopant atoms may play important roles in the cage formation of the transition-metal-doped Si clusters. Moreover, it is found that the localization of charge on the Au dopant atoms in Si n Au+ determines the extent of complex formation with argon and xenon.
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