Abstract
The Global Climate Observing System Reference Upper-Air Network (GRUAN) with high-vertical-resolution radiosonde data at three Arctic stations and European Centre for Medium-Range Weather ...Forecasts (ECMWF) reanalysis data (ERA5) were used to investigate the characteristics of multiple temperature inversions (TI) and humidity inversions (HI) in this study. It is found that surface-based inversion (SBI) at two coastal stations exists throughout the whole year, mainly due to the surface cooling in cold months, advection warm months, and the orography of the stations. The seasonal variation of surfaced-based HI (SBHI) frequency is similar to that of SBI, and its intensity is greater in summer because of the larger air moisture content. The frequency of the first elevated TI (EI1) and HI (EHI1) are both higher than that of the surface-based ones. The second elevated TI/HI layer (EI2/EHI2) is shallower and weaker than that of the EI1/EHI1. At two coastal stations, EI1 caused by warm advection is thicker and stronger than that caused by subsidence. At the station farther from the coast, EI1 caused by subsidence is higher, thinner, and stronger. The top height and depth of the EHI2 both show seasonal variations, with larger values in the cold months. EHI1 tends to be formed by the TI, whereas EHI2 is dominant by humidity advection at all studied stations. HI under the influence of TI is usually thicker and stronger than that formed by humidity advection. The coexistence of EI and EHI is the most frequent inversion structure at these stations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Aurora kinase inhibitors have attracted a great deal of interest as a new class of antimitotic agents. We report a novel class of Aurora inhibitors based on a pentacyclic scaffold. A prototype ...pentacyclic inhibitor 32 (AKI-001) derived from two early lead structures improves upon the best properties of each parent and compares favorably to a previously reported Aurora inhibitor, 39 (VX-680). The inhibitor exhibits low nanomolar potency against both Aurora A and Aurora B enzymes, excellent cellular potency (IC50 < 100 nM), and good oral bioavailability. Phenotypic cellular assays show that both Aurora A and Aurora B are inhibited at inhibitor concentrations sufficient to block proliferation. Importantly, the cellular activity translates to potent inhibition of tumor growth in vivo. An oral dose of 5 mg/kg QD is well tolerated and results in near stasis (92% TGI) in an HCT116 mouse xenograft model.
An iron-based complex Fe(II)-BTC (BTC = 1,3,5-benzenetricarboxylic acid) modified electrode as a mimetic enzyme sensor was designed for detecting the photorelease of nitric oxide (NO) in sodium ...nitroprusside (SNP). The Fe(II)-BTC complex film was electrodeposited on the surface of a glassy carbon electrode, and its morphology and composition were characterized by scanning electron microscopy, energy-dispersive spectrometer and Fourier transform infrared. The response of the mimetic enzyme sensor was investigated by diverse electrochemical methods, including voltammetry, electrochemical impedance spectroscopy, chronocoulometry and chronoamperometry. The sensor exhibited good catalytic activity for electrochemical oxidation of NO and followed Michaelis–Menten behaviors. The electrocatalytic oxidation mechanism for NO was proposed. The mimetic enzyme sensor not only had the features of easy preparation, low cost and high stability, but also had a wide linear range from 18 nmol L−1 to 9 μmol L−1 and a low detection limit of 7.2 nmol L−1, which had been used to detect the NO photorelease from SNP successfully.
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•An iron-based complex Fe(II)-BTC modified electrode as a mimetic enzyme sensor was fabricated by electrodeposition.•The Fe(II)-BTC films displayed good catalytic activity for electrochemical oxidation of nitric oxide (NO).•The electrocatalytic oxidation mechanism for NO was proposed.•The mimetic enzyme sensor had good stability and reproducibility, as well as a wide linear range and a low detection limit.•The mimetic enzyme sensor was used to detect the NO photorelease from sodium nitroprusside successfully.
H-bond cross-linked polyimide (HPI) nanofiber-modified polyethylene (PE) composite separators with high thermal stability, excellent electrolyte wettability, and improved electrochemical performance ...are prepared by electrospinning and alkaline hydrolysis processes. Due to the high thermal stability of the layer of HPI nanofiber, the dimension stability of the HPI@PE separator is greatly enhanced compared to the PE separator, without obvious thermal shrinkage at 200 °C. In comparison to the PE separators, lithium-ion batteries (LIBs) assembled with the HPI@PE composite separators show better cycling performance and rate capability, which are ascribed to the high polarity and developed porosity of the HPI nanofiber layer, which gives the separator excellent electrolyte wettability (electrolyte uptake and retention are 204 and 65%, respectively), low bulk resistance (3.1 Ω), and high ionic conductivity (0.46 mS cm–1). Therefore, the assembled Li/HPI@PE/LiCoO2 cell achieves a specific capacity of 105.5 mA h g–1 as well as a capacity retention of 80.7% after 200 cycles at the discharge rate of 1 C. These results indicate that the prepared HPI@PE separator is applicable toward safe, long-life, and high-rate LIBs.
•A porous polythiophene/UiO-66 extraction coating was prepared by electrodeposition.•UiO-66 enhanced the uniformity of the coating and decreased the stacking of PEDOT.•The extraction efficiency of ...the coating was improved by more than 100 times.•Adsorption isotherm indicated π stacking effect played dominant role in extraction.•Seven types of VOCs in ion-exchange resins was determined by HS-SPME/GC-FID.
A Poly (3,4-ethylenedioxothiophene) (PEDOT)/UiO-66 composite was electrodeposited on an etched stainless-steel wire as head-space solid-phase microextraction (HS-SPME) coating. A robust, well controlled thickness, and uniform coating of metal organic framework composites can be realized by the electrodeposited strategy. The incorporated UiO-66 not only enhanced the uniformity and stability of the composite coating, but also effectively decreased the stacking phenomenon of PEDOT and improved its extraction efficiency, which was over 100 times higher than that of the PEDOT coating without UiO-66. The composite coating was used to enrich seven types of volatile organic compounds (VOCs) in ion-exchange resins, including methyl cyclohexane, benzene, toluene, ortho-xylene, styrene, para-xylene and divinyl-benzene. The results of adsorption isotherm analysis showed that π stacking effect played dominant role between the composite coating and VOCs in the extraction process. The composite coating was characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared and thermogravimetric analysis, respectively. A determination method for seven kinds of VOCs was established by HS-SPME coupled with gas chromatography-flame ionization detection (GC-FID). Under the optimal experimental conditions, the detection linear range (LRs) was 0.09-100 ng mL−1, and the detection limit (LODs) was 0.03-0.06 ng mL−1 (S/N = 3). The method was applied for the migration detection of VOCs in four types of ion-exchange resin, which showed satisfactory recovery (84.5-117.2%).
Abstract
This study explores parental mediation of smartphone use by rural‐to‐urban migrant children in China. A total of 16 migrant parents participated in semi‐structured interviews. Reflexive ...thematic analysis is conducted to analyse the transcribed interviews. Findings indicate that migrant parents are highly concerned about the harmful impact of smartphone use on their children. Three parental mediation strategies mentioned in previous studies are confirmed, that is, restriction mediation, monitoring and active mediation, whereas a new mediation strategy, namely, activity substitution, is identified in this study. This study finds that the parents use a combination of different strategies for parental mediation. Furthermore, four themes identify the challenges in parental mediation: Lack of time, skills and helper for parenting and father's absence, inconsistency between parents' restrictive mediation and own overuse practices, the adverse effect of COVID‐19 and the need for professional help. Finally, implications for social work practice are discussed.
A cauliflower-shaped Fe/Fe-BTC nanocomposite was prepared by one-step controlled electrodeposition, which exhibited tunable morphology, electrocatalysis and extraction applications.
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...•A Fe/Fe-BTC nanocomposite was prepared by cathodic electrodeposition.•The properties of Fe-BTC film varied with thedeposition potential.•The electrosynthesis mechanism of Fe/Fe-BTC nanocomposite was proposed.•The Fe/Fe-BTC film had application potential in electrocatalysis and extraction.
A cauliflower-shaped Fe/Fe-BTC nanocomposite was prepared by one-step controlled cathodic electrodeposition method. The obtained Fe-BTC nanoscale film was characterized by scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FT-IR), thermogravimetric analysis (TGA) and electrochemical measurements, indicating its morphology, structure and electrochemical activities varied with the applied cathodic potential. The electrodeposition process was investigated thoroughly and the electrosynthesis mechanism of the Fe/Fe-BTC nanocomposite was proposed. The Fe/Fe-BTC nanoscale film deposited at −1.5 V exhibited the loosest morphology and best electrochemical activity, which showed the best application potential in electrocatalytic H2O2 reduction and adsorption of diethyl phthalate (DEP) and dibutyl phthalate (DBP). The iron-based binary metal organic materials were designable and could be applied in the field of electrocatalysis and extraction.
Fruit color is closely associated with the commercial value of citrus fruit. Postharvest green lemon is prone to non-uniform coloration during storage, which negatively affects its marketability. To ...better control postharvest lemon color, it is vital to understand the mechanism for the uneven degreening of lemon fruit. In this study, we investigated the chloroplast development, chlorophyll, carotenoid and hormone contents and related genes involved in lemon degreening by morphological, physiological, and biochemical analysis and transcriptomics. During room temperature storage, the green lemon fruit showed degreening on the day10, and exhibited complete yellowing on the day 40 of storage. The fruit were yellow-green variegated from day 10 to day 40 after harvest. The degreened part showed decreases in chlorophyll, brassinolide (Br), indoleacetic acid (IAA) and gibberellin (GA3) content while accumulation of carotenoids and abscisic acid (ABA). Ethephon (CEPA) treatment accelerated the degreening of green lemon, and decreased the chlorophyll a and b, and IAA contents, while increased the contents of phytofluene, phytoene, and ABA in the flavedo. However, opposite results were obtained under gibberellic acid (GA3) treatment. Transcriptomic profiling analysis under different treatments revealed that the expression of PPH, PSY, NCED4, bHLH25, ERF106 and NAC72 has the highest correlation with pigment metabolism. These results indicate that the uneven degreening of green lemon is associated with uneven distribution of hormones and pigments in the flavedo.
•The uneven degreened part showed decrease in chlorophylls and increase carotenoids.•The uneven degreened is associated with uneven distribution of hormones and pigments.•CEPA accelerated fruit degreening, while the opposite result was obtained with GA3.•The genes for pigment metabolism, pathways regulated flavedo coloration.
A series of single-metal carbonates and Pb-Zn mixed-metal carbonates were prepared as catalysts for alcoholysis of urea with 1,2-propylene glycol (PG) for the synthesis of propylene carbonate (PC). ...The mixed carbonates all show much better catalytic activities than the single carbonates, arising from a strong synergistic effect between the two crystalline phases, hydrozincite and lead carbonate. The mixed carbonate with Pb/Zn = 1:2 gives the highest yield of PC, followed by the mixed carbonate with Pb/Zn = 1:3. Furthermore, Taguchi method was used to optimize the synthetic process for improving the yield of PC. It is shown that the reaction temperature is the most significant factor affecting the yield of PC, followed by the reaction time, and that the optimal reaction conditions are the reaction time 5 h, the reaction temperature 180 °C and the catalyst amount 1.8 mass%, resulting in the highest PC yield of 96.3%.
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