A series of single-phase broadband white-light-emitting Sr5(PO4)3F:Eu(2+),Mn(2+) phosphors were prepared by a solid state reaction. The luminescence property, and the crystal and electronic ...structures of the fluorophosphates were studied by photoluminescence analysis, XRD Rietveld refinement and density functional theory calculation (DFT), respectively. Under near ultraviolet excitation in the 250 to 430 nm wavelength range, the phosphors exhibit two emission bands centered at 440 and 556 nm, caused by the Eu(2+) and Mn(2+) ions. By altering the relative ratios of Eu(2+) and Mn(2+) in the compounds, the emission color could be modulated from blue to white. The efficient energy transfer from the Eu(2+) to Mn(2+) ions could be ascribed to the well crystallized host lattice and the facile substitution of Eu(2+) and Mn(2+) for Sr(2+) sites due to similar ionic radii. A series of fluxes were investigated to improve the photoluminescence intensity. When KCl was used as flux in the synthesis, the photoluminescence intensity of Sr5(PO4)3F:Eu(2+),Mn(2+) was enhanced by 85% compared with no fluxes added. These results demonstrate that the single-phase Sr5(PO4)3F:Eu(2+),Mn(2+) with enhanced luminescence efficiency could be promising as a near UV-convertible direct white-light-emitting phosphor for WLED applications.
Construction of three-dimensional (3D) flower-like nanostructures with controlled morphologies has emerged as an attractive tool by scientists in the marine electric field sensor research field due ...to their peculiar structural features. Herein, novel 3D flower-like Ag-CF capacitive composite electrodes have been created by an eco-friendly water-bath strategy via AgNO
as a sliver source and subsequently compounded with carbon fibers (CFs) pretreated by thermal oxidation. A series of electrode samples with various morphologies obtained by modulating different reaction times and temperatures bring about the dominant formation mechanism of these nanostructures and the influence behavior on the CF electrode in detail. Especially, the 3D flower-like Ag-CF electrode shows a large surface area acquired under the conditions of 80 °C and 15 min, which can provide more electroactive sites in electrochemical analysis and exhibit a maximum areal specific capacitance of 619.75 mF·cm
at a scanning speed of 10 mV·s
. This is mainly due to the synergistic behavior of the unique 3D flower-like morphology and the large specific surface area of CFs. Furthermore, a cylinder-shaped Ag-CF sensor is designed, which delivers a superior potential difference of 33.08 μV, a potential difference drift of 18.62 μV/24 h for 30 days, and a self-noise of 0.92 nV/rt (Hz)@1 Hz. In this work, the intriguing synthesis strategy can be a promising facile approach to manufacture the controllable 3D flower-like Ag-CF electrode for electric field sensor applications.
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IJS, KILJ, NUK, PNG, UL, UM
This paper considers the m-machine flow shop scheduling problem with the no-wait constraint to minimize total completion time which is the typical model in steel production. First, the asymptotic ...optimality of the Shortest Processing Time (SPT) first rule is proven for this problem. To further evaluate the performance of the algorithm, a new lower bound with performance guarantee is designed. At the end of the paper, numerical simulations show the effectiveness of the proposed algorithm and lower bound.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
The anti-hepatocellular carcinoma effects of TET are acknowledged, but its application is hindered by its poor water solubility and low bioavailability. Conventional methods for nanocrystal ...preparation are laborious and lack control. To address these limitations, we propose employing the microfluidic method in the preparation of TET nanocrystals, aiming to enhance the aforementioned constraints. The objectives of this study were to prepare TET nanocrystals (TET-NC@GL) using a Y-microfluidic method with glycyrrhetinic acid (GL) as a stabilizer. The optimal preparation prescription was determined through a single-factor test and Box-Behnken response surface method. Additionally, the nanocrystals prepared with the commonly used stabilizer polyvinylpyrrolidone K30 (PVPK30), known as TET-NC@PVPK30, were characterized and evaluated for their toxicity to HepG2 cells. Hybridized nanocrystals (TET-HNC@GL and TET-HNC@PVPK30) were synthesized using a water-soluble aggregation-induced emission (AIE) fluorescent probe (TVP). Qualitative and quantitative cellular uptake experiments were conducted using these hybridized nanocrystals. Conducting
in vivo
pharmacokinetic assays evaluates the relative bioavailability of nanocrystals. The results indicated that TET-NC@GL, optimized using the response surface method, had a particle size of 136.47 ± 3.31 nm and a PDI of 0.219 ± 0.002. The administration of TET-NC@GL significantly enhanced the cell inhibition rate compared to the TET group and the TET-NC@PVPK30 group (
P
< 0.01). Moreover, the qualitative and quantitative cellular uptake results revealed a significant enhancement in cellular uptake in the TET-HNC@GL administration group compared to the TET-HNC@PVPK30 group (
P
< 0.01).
In vivo
pharmacokinetic results showed that the bioavailability of TET-NC@GL group was 3.5 times higher than that of the TET group. The results demonstrate the successful preparation of TET-NC@GL nanocrystals.
Graphical Abstract
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Lanthanide metal-organic frameworks (Ln-MOFs) are featured by their tolerance to water and dense structure. In this work, an amine-functionalized Ln-MOF was facilely synthesized by coordination of ...terbium with 2-aminoterephthalic acid under the condition of microwave irradiation. The crystal structure was characterized by single crystal X-ray diffraction, FT-IR, Raman, TG-DTA and XPS analysis. The basic catalytic activity of the NH2-Tb-MOF was evaluated for Knoevenagel condensation and Henry reactions. Apart from the high activity and 100% selectivity to the condensation product, the NH2-Tb-MOF catalyst could be easily recycled and reused owing to the high stability of the MOF framework formed by coordination of Tb3+ with carboxylic groups. Remarkably, the NH2-Tb-MOF exhibited size-selective catalysis to substrates. For the small-sized reactants, it displayed comparable activity to the homogeneous catalyst of aniline owing to the high dispersion of NH2− active sites and the low diffusion limits. However, in the same reaction system, extremely poor activity in Knoevenagel condensation and Henry reaction for the bulky substrate 4-(tert-butyl) benzaldehyde was observed due to the both effects of substitute and inhibition of diffusion into the micropores. Crystal structure analysis provided a mechanistic evidence that the heterogeneous base catalysis arose from the amino groups densely distributed inside the micropores.
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•NH2-Tb-MOF is facilely synthesized under microwave irradiation condition.•Structure characterization demonstrates the amino groups in the micropores.•The activity of NH2-Tb-MOF as solid base catalyst is evaluated.•The NH2-Tb-MOF shows a selective catalysis towards small sized reactants.•The stable structure affords the heterogeneous catalyst recyclable and reusable.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A series of cobalt nickel phosphates are prepared via a mild chemical precipitation method followed by calcination at a low temperature. With variation of Co/Ni molar ratio, the compositions and ...microstructures of the as-prepared samples are modulated and their electrochemical performances as battery-type materials are optimized. Electrochemical measurements by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) technique and electrochemical impedance spectroscopy (EIS) reveal that the flower-like CoNi2(PO4)2 with the molar ratio of Co/Ni = 1:2 exhibits a high specific capacity of 630.4 C g−1 at the current density of 1 A g−1, and an excellent cycling stability of 84.3% capacity retention after 1000 cycles. Furthermore, a hybrid supercapacitor, fabricated with the CoNi2(PO4)2 as positive and graphene as negative electrode material, exhibits a high specific capacitance of 103 F g−1 at the current density of 1 A g−1, along with a high energy density of 32.2 Wh kg−1 at the power density of 377.6 W kg−1, and even 21.7 Wh kg−1 at 4.9 kW kg−1. These figures demonstrate that cobalt nickel phosphates as electrode materials with the optimized composition and microstructure may hold promising application in energy storage devices.
•Cobalt nickel phosphates are prepared.•The composition and microstructure are modulated with variation of Co/Ni ratio.•The electrode properties as battery-type material are optimized.•The flower-like CoNi2(PO4)2 shows high-performance hybrid capacitor application.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A mathematical model is established for the preheating commissioning process of waxy crude oil pipelines. The governing equations are solved by the finite volume method and the finite difference ...method. Accordingly, numerical computations are made for the Niger crude oil pipeline and the Daqing-Tieling 3rd pipeline. The computational results agree well with the field test data. On this basis, fluid temperature in the process of the preheating commissioning is studied for single station-to-station pipeline. By comparing different preheating modes, it is found that the effect of forward preheating is the best. Under different preheating commissioning conditions, the optimal combination of outlet temperature and flow rate is given.
Identifying the gut microbiota associated with host immunity in the AIDS stage.
We performed a cross-sectional study.
We recruited people with HIV (PWH) in the AIDS or non-AIDS stage and evaluated ...their gut microbiota and metabolites by using 16S ribosomal RNA (rRNA) sequencing and liquid chromatography-mass spectrometry (LC-MS). Machine learning models were used to analyze the correlations between key bacteria and CD4 + T cell count, CD4 + T cell activation, bacterial translocation, gut metabolites, and KEGG functional pathways.
We recruited 114 PWH in the AIDS stage and 203 PWH in the non-AIDS stage. The α-diversity of gut microbiota was downregulated in the AIDS stage ( P < 0.05). Several machine learning models could be used to identify key gut microbiota associated with AIDS, including the logistic regression model with area under the curve (AUC), sensitivity, specificity, and Brier scores of 0.854, 0.813, 0.813, and 0.160, respectively. The decreased key bacteria ASV1 ( Bacteroides sp.), ASV8 ( Fusobacterium sp.), ASV30 ( Roseburia sp.), ASV37 ( Bacteroides sp.), and ASV41 ( Lactobacillus sp.) in the AIDS stage were positively correlated with the CD4 + T cell count, the EndoCAb IgM level, 4-hydroxyphenylpyruvic acid abundance, and the predicted cell growth pathway, and negatively correlated with the CD3 + CD4 + CD38 + HLA-DR + T cell count and the sCD14 level.
Machine learning has the potential to recognize key gut microbiota related to AIDS. The key five bacteria in the AIDS stage and their metabolites might be related to CD4 + T cell reduction and immune activation.
Protein phosphatase 2 C (PP2C) gene family is known for regulating a variety of abiotic stresses in plants. However, little is currently understood about this gene family in jute. In this study, a ...total of 60 CcPP2C genes were identified in jute, which were named from CcPP2C1 to CcPP2C60 according to the order of their physical coordinates. These CcPP2C proteins contained about 162–1324 amimo acids. Their isoelectric points varied in the range of 4.51–9.45, and their molecular weights varied from 18.307 to 146.906 kDa. The evolutionary tree of PP2Cs in jute and Arabidopsis indicated that PP2Cs can be divided into 12 branches. Sixty-seven collinear gene pairs were identified between 42 CcPP2Cs and 62 AtPP2Cs by analyzing the whole genome collinearity data of jute and Arabidopsis. The analyses of conserved motifs in these CcPP2C proteins and cis-elements in the promoters revealed that CcPP2Cs might play an extensive role in responses to various abiotic stresses in jute. Particularly, the expression patterns of CcPP2Cs in group A under salt treatments showed that CcPP2C51 was up-regulated under various stress treatments. And CcPP2C51 was localized in the nucleus and cell membrane. In Arabidopsis, the overexpression of CcPP2C51 positively regulated the salt-tolerance genes. Also, the overexpression of CcPP2C51 improved the salt tolerance of jute regenerated roots. This study revealed the origin and evolution of PP2C genes in jute, and provides potential possibilities for molecular breeding of jute.
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•A total of 60 CcPP2C genes were identified in jute•These 60 CcPP2C genes are evolutionarily conserved and might be involved in stresses•Different expression patterns were observed under salt treatment in CcPP2Cs•CcPP2C51 was found to be localized in the nucleus and cell membrane•Overexpression of CcPP2C51 in Arabidopsis and jute resulted in salt tolerance
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
White xerogel powder of yttrium tungstate-chloride was synthesized, and its photoluminescence properties were investigated. Under the excitation of 254
nm, the xerogel phosphor exhibits emission ...ranging from 300 to 650
nm. This luminescent spectrum is identified as two emission bands of 300–400 and 400–650
nm due to different emission mechanism. While the emission band of 300–400
nm is ascribed to the charge transfer (CT) from O to metal W, the emission of 400–650
nm is attributed to electron–hole (e
−–h
+) carrier emission related to oxygen vacancies. By calcining the sample in reducing atmosphere, the number of oxygen vacancies acting as luminescence centers is increased. As a result, the emission intensity of 400–650
nm is significantly enhanced. Based on electron paramagnetic resonance and spectral analysis, the mechanism of peroxy-radical hole traps (PRHT) is proposed for the luminescence of 400–650
nm.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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