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1.
Environ Sci Pollut Res Int ; 31(30): 42792-42809, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38878248

RESUMO

In this work, salicylic acid (SA) was used to induce the self-assembly of octadecyl trimethyl ammonium chloride (OTAC), a cationic surfactant, into three-dimensional wormlike micelle aggregates. These aggregates act as a soft template for hierarchical MgAl hydrotalcite (LDH) to create a multi-level pore structure adsorption material. Scanning electron microscopy characterization showed that the surface of the hierarchical hydrotalcite exhibited a dense layered structure, unlike the monolayer structure of ordinary hydrotalcite. Furthermore, the hierarchical MgAl-LDH possesses a significantly larger specific surface area (113.94 m2/g) and wide pore size distribution ranging more extensively from 2 to 80 nm, which significantly has an impressive adsorption effect on sulfonated lignite (SL), with a maximum adsorption capacity of 192.7 mg/g at pH = 7. Extensive research has been conducted on the adsorption mechanism of hierarchical MgAl-LDH, attributing it to surface adsorption due to the unique multi-level structure of the adsorbent. After two cycles of regeneration experiments, the adsorption capacity of the adsorbent remained at a high level of 179.1 mg/g, demonstrating the excellent renewability of hierarchical MgAl-LDH. Moreover, the hierarchical hydrotalcite showed high adsorption capacity in the adsorption of sulfonated lignite, which was attributed to its larger specific surface area and superior pore structure to expose more active sites.


Assuntos
Hidróxido de Alumínio , Hidróxido de Magnésio , Hidróxido de Alumínio/química , Hidróxido de Magnésio/química , Adsorção
2.
Front Physiol ; 13: 1034014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338468

RESUMO

Background: Abdominal aortic aneurysm (AAA) is a degenerative disease that causes health problems in humans. However, there are no effective drugs for the treatment of AAA. Artemisia annua L. (A. annua) is a traditional herbal that has been widely used in cardiovascular disease. Based on network pharmacology and molecular docking technology, this study predicted the practical components and potential mechanisms of A. annua inhibiting the occurrence and development of AAA. Methods: The main active ingredients and targets of A. annua were screened through the TCMSP database; the GeneCards, OMIM, PharmGkb, and TTD databases were used to search for the targeted genes of AAA and map them to the targets of the active ingredients to obtain the active ingredient therapy of A. annua. The targets of AAA were to construct a protein interaction network through the STRING platform. R software was used to carry out the enrichment analysis of GO and KEGG for relevant targets, and Cytoscape was used to construct the active ingredient-target network prediction model of A. annua. Finally, AutoDock Vina was used to verify the results of the active ingredients and critical targets. Results: The main active ingredients obtained from A. annua for the treatment of AAA include quercetin, luteolin, kaempferol, isorhamnetin, and artemetin, as well as 117 effective targets, including RELA, MAPK14, CCND1, MAPK1, AKT1, MYC, MAPK8, TP53, ESR1, FOS, and JUN. The 11 targeted genes might play a key role in disease treatment. Enriched in 2115 GO biological processes, 159 molecular functions, 56 cellular components, and 156 KEGG pathways, inferred that its mechanism of action might be related to PI3K-Akt signaling pathway, fluid shear stress, atherosclerosis, and AGE-RAGE signaling pathway. Molecular docking results showed that the top five active components of A. annua had a good affinity for core disease targets and played a central role in treating AAA. The low binding energy molecular docking results provided valuable information for the development of drugs to treat AAA. Conclusion: Therefore, A. annua may have multiple components, multiple targets, and multiple signaling pathways to play a role in treating AAA. A. annua may have the potential to treat AAA.

3.
Food Chem ; 383: 132424, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35182869

RESUMO

In the present study, the differences in the antioxidant capability, metabolite composition and fungal diversity in peach gum with various colours were investigated. Metabolomics revealed that peach gum comprised many small-molecule metabolites (including primary and secondary metabolites), and most polyphenols (such as flavonoids and phenolic acids) showed a significantly positive relationship with the colour deepening, total phenol content and antioxidant capability. Using fungal diversity analysis, the abundance of five fungi at the genus level increased with peach gum colour deepening, and these fungi demonstrated a significantly positive relationship with two defense hormones (salicylic acid and abscisic acid) and most polyphenols (particularly flavonoids). The gummosis pathogenic fungus Botryosphaeria was among the five fungi, suggesting that peach gum colouring may reflect plant defense responses against pathogenic fungi. Additionally, the concentrations of 12 flavonoids in peach gum samples were detected based on LC-QQQ/MS, among which hesperetin, naringenin and eriodictyol were the most abundant.


Assuntos
Ascomicetos , Prunus persica , Antioxidantes , Ascomicetos/genética , Flavonoides , Polifenóis
4.
J Hazard Mater ; 403: 123597, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32781278

RESUMO

A new diffusive gradients in thin films technique (HR-ZCA DGT) was developed for simultaneous two-dimensional (2-D) chemical imaging of sulfides, metallic cations and oxyanions (S, Cd, Co, Fe, Cu, Mn, Ni, Pb, Zn, As, Cr, Mo, Sb, Se, V, P and W) at the submillimeter scale, combined with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis. A novel binding gel was prepared using a double precipitation method with AgI and zirconium oxide (Zr-oxide) deposited sequentially on a preformed Chelex-100 resin gel. A good linear relationship was observed (R2>0.99) between mass accumulation of the 17 assessed elements on the binding gel and the corresponding standardized laser ablation signals (signals of elements divided by signals of internal standard 13C), proving the feasibility of LA-ICP-MS analysis. Good analytical precision (RSD<12 %) was achieved for all 17 elements. A hybrid sensor comprising the novel DGT binding gel overlying an O2 planar optrode was then tested in sediments to evaluate the dynamics of O2 and multiple elements. Results showed that the mobility of As, P and W were controlled by precipitation/dissolution processes with Fe/Mn oxides. V, Co, Ni, Zn, Mo, Cd and Sb were released at the sediment surface with the oxidation of iron sulfides.

5.
Rev Sci Instrum ; 91(1): 015007, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012618

RESUMO

In this paper, a fiber Bragg grating (FBG) temperature measurement method for intersatellite laser link is studied. Based on the analysis of the FBG temperature measurement method, the FBG sensing demodulation system is built to calibrate its wavelength and temperature parameters. The experimental data of temperature gradient monitoring are compared with the on-orbit real-time temperature data of a satellite's solar array measured by the thermistor to verify the temperature monitoring accuracy and stability of the FBG sensing demodulation system. The FBG sensing demodulation system and the thermistor temperature measurement system are compared under the same environmental conditions during the constant temperature period, the continuous heating phase and the natural cooling phase. The results show that during the constant temperature period, the temperature fluctuation range and standard deviation of the FBG sensing demodulation system are ±0.16 °C and 0.08 °C, respectively, which is significantly better than the performance of the thermistor temperature measurement system, whose temperature fluctuation range and standard deviation are ±5.92 °C and 1.08 °C, respectively. The temperature response speed of the former is significantly faster than that of the latter during the continuous heating phase and the natural cooling phase.

6.
Sensors (Basel) ; 19(7)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934942

RESUMO

A novel Fabry⁻Perot (F⁻P) interferometer model based on the ultra-small gradient-index (GRIN) fiber probe is investigated. The signal arm of the F⁻P interferometer is organically combined with the ultra-small GRIN fiber probe to establish the theoretical model of the novel F⁻P interferometer. An interferometer experimental system for vibration measurements was built to measure the performance of the novel F⁻P interferometer system. The experimental results show that under the given conditions, the output voltage of the novel interferometer is 3.9 V at the working distance of 0.506 mm, which is significantly higher than the output voltage 0.48 V of the single-mode fiber (SMF) F⁻P interferometer at this position. In the range of 0.1⁻2 mm cavity length, the novel interferometer has a higher output voltage than an SMF F⁻P interferometer. Therefore, the novel F⁻P interferometer is available for further study of the precise measurement of micro vibrations and displacements in narrow spaces.

7.
Chemosphere ; 223: 108-116, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30772589

RESUMO

Differences in trophic status can lead to different water quality and sediment geochemistry characteristics, influencing antimony (Sb) mobility in sediments and its release into the water column. In this study, seasonal sampling was conducted in algal- and macrophyte-dominated zones of Lake Taihu, China. High-resolution dialysis (HR-Peeper) and diffusive gradients in thin films (DGT) techniques were used to measure soluble Sb and DGT-labile Sb in the sediment-water profiles at a 4 mm vertical resolution. Results showed that total Sb in sediments from the two zones were on average 3.50 mg/kg and 3.21 mg/kg in the algal- and macrophyte-dominated zones, respectively, with the residual fraction being 96.3% and 95.4% of the total Sb contents in the two zones. In winter, soluble Sb concentrations in both zones increased. This was probably due to the oxidation of Sb(III) to Sb(V) by Mn and Fe oxides. In summer and autumn, soluble Sb concentrations in the algal-dominated region remained low. This is attributed to the dominance of insoluble Sb(III) in sediments under anoxic conditions under eutrophic environments. In contrast, soluble Sb concentrations in the macrophyte-dominated zone were significantly high in summer and were 4.15-times higher than limits set by the World Health Organization (WHO). This likely resulted from the photochemical and rhizospheric oxidation of insoluble Sb(III) compounds. It is suggested that Sb contamination in the sediment-water system of the macrophyte-dominated zone deserves additional attention.


Assuntos
Antimônio/análise , Sedimentos Geológicos/química , Lagos/química , Estações do Ano , Água/química , China , Phaeophyceae , Plantas , Solubilidade , Poluentes Químicos da Água/análise
8.
Chemosphere ; 220: 476-485, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30594799

RESUMO

Studies of dredging effectiveness, especially the ones that last for several years, are scarce. In this study, we evaluated effectiveness of dredging performed for six years on controlling cobalt (Co), zinc (Zn), and nickel (Ni) contamination of sediments. High-resolution dialysis (HR-Peeper) and diffusive gradients in thin films (DGT) methods were applied to analyze the non-dredged and post-dredging sediments. The soluble and DGT-labile Co and Ni content declined by 22% and 44% (soluble) and by 16% and 26% (labile) in April, July and October in the post-dredging region. In contrast, their concentrations increased by 105% and 9% (soluble) and 322% and 27% (labile) in January. These changes in the dredging effects were caused by the corresponding changes in the reducible and residual fractions of Co and the residual fraction of Ni in sediments in the dredged site, respectively. Soluble and DGT-labile Zn decreased on average by 23% and 29% in July and October and increased on average by 151% and 52% in April and January in the post-dredging region. The different Zn mobility in the post-dredging region was controlled by the reducible fraction of Zn. The results revealed positive influence of dredging engineering in summer, autumn and/or spring and negative one in winter. Therefore, an accurate assessment of dredging effectiveness should take its seasonal variation into consideration.


Assuntos
Fracionamento Químico/métodos , Cobalto/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Níquel/análise , Poluentes Químicos da Água/análise , Zinco/análise , Estudos de Amostragem
9.
ACS Appl Mater Interfaces ; 8(31): 19892-8, 2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27408988

RESUMO

Continuous fluorescence imaging of intracellular ions in various spectral ranges is important for biological studies. In this paper, fluorescent calcium-selective nanospheres, including calix[4]arene-functionalized bodipy (CBDP) or 9-(diethylamino)-5-[(2-octyldecyl)imino]benzo[a]phenoxazine (ETH 5350) as the chromoionophore, were prepared to demonstrate intracellular calcium imaging in visible or near-IR regions, respectively. The fluorescence of the nanospheres was controlled by the chromoionophore, and thus the spectral range for detection was adjustable by choosing the proper chromoionophore. The response time of the nanospheres to calcium was typically 1 s, which allowed accurate measurement of intracellular calcium. These nanospheres were loaded into cells through free endocytosis and exhibited fluorescence for 24 h, and their intensity was correlated with the elevation of intracellular calcium upon stimulation. The successful demonstration of calcium imaging by use of ion-selective nanospheres within two spectral ranges in 24 h supported that these nanospheres could be applied for continuous imaging of intracellular ions with adjustable spectra.


Assuntos
Nanosferas , Cálcio , Íons , Espectrometria de Fluorescência
10.
Analyst ; 139(1): 52-4, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24213202

RESUMO

A highly stable, long wavelength polarity sensitive probe, 8-nitrophenyl-3,5-dipiperidine-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (NPBDP), was developed for living cell imaging of intracellular lipid droplets by fluorescence microscopy.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Líquido Intracelular/química , Lipídeos de Membrana/análise , Imagem Óptica/métodos
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