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1.
Opt Express ; 32(4): 6567-6574, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439356

RESUMO

This paper present a novel, integrated compressed ultrafast photography system for comprehensive measurement of the aluminium planar wire array Z-Pinch evolution process. The system incorporates a large array streak camera and embedded encoding to improve the signal-to-noise ratio. Based on the "QiangGuang-I" pulsed power facility, we recorded the complete continuous 2D implosion process of planar wire array Z-Pinch for the first time. Our results contribute valuable understanding of imploding plasma instabilities and offer direction for the optimization of Z-Pinch facilities.

2.
Food Funct ; 15(6): 3158-3173, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38440931

RESUMO

The gut health-promoting properties of saponin-rich Polygonatum cyrtonema Hua (FP) fermented with Lactobacillus plantarum P9 were explored in a dextran sulfate sodium (DSS)-induced colitis mouse model. FP supplementation effectively inhibited DSS-induced physiological alteration and impaired immune responses by reducing the disease activity index (DAI) score and restoring the T helper (Th) 1/Th2 and regulatory T (Treg)/Th17 ratios. In addition, FP supplementation protected the gut barrier function against DSS-induced damage via upregulation of zonula occludens (ZO)-1 and occludin and downregulation of pro-inflammatory cytokines, including interleukin (IL)-1ß, tumor necrosis factor-α (TNF-α), IL-18, and the granulocyte-macrophage colony-stimulating factor (GM-CSF). This study further elucidated the potential mechanisms underlying the FP-mediated suppression of the plasticity of type 3 innate lymphoid cells (ILC3) and subsequent macrophage polarization. Therefore, the FP supplementation effectively restored mucosal immune homeostasis and enhanced gut integrity. In addition, it suppressed the growth of Escherichia-Shigella and Enterococcus and promoted the enrichment of probiotics and short-chain fatty acid-producing microbes, such as Romboutsia, Faecalibaculum, and Blautia. In conclusion, P. cyrtonema Hua fermented with L. plantarum P9 might be a promising dietary intervention to improve gut health by sustaining overall gut homeostasis and related gut integrity.


Assuntos
Colite , Polygonatum , Animais , Camundongos , Dextranos , Imunidade Inata , Linfócitos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Homeostase , Interleucina-1beta , Sulfatos , Sódio
3.
Rev Sci Instrum ; 93(11): 113303, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461448

RESUMO

Streak cameras are powerful imaging instruments for studying ultrafast dynamics with the temporal resolution ranging from picosecond to attosecond. However, the confined detection area limits the information capacity of streak cameras, preventing them from fulfilling their potential in lidar, compressed ultrafast photography, etc. Here, we designed and manufactured a large-format streak tube with a large-size round-aperture gate, a spherical cathode, and a spherical screen, leading to an expanded detection area and a high spatial resolution. The simulation results show that the physical temporal resolution of the streak tube is better than 45 ps and the spatial resolutions are higher than 14 lp/mm in the whole area of 24 × 28 mm2 on the cathode. The experiments demonstrate the streak tube's application potential in weak light imaging benefiting from the imaging magnification of 0.79, a photocathode radiance sensitivity of 37 mA/W, a radiant emitting gain of 11.6 at the wavelength of 500 nm, and a dynamic range higher than 512:1. Most importantly, in the photocathode area of Φ35 mm, the static spatial resolutions at the center and the edge along the slit (R = 16 mm) reach 32 and 28 lp/mm, respectively, and are higher than 10 lp/mm in the whole area of 24 × 28 mm2 on the cathode, allowing for a considerable capacity for spatial information.

4.
Polymers (Basel) ; 14(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36501491

RESUMO

With the continuous development of road construction and maintenance, SBS(Styrene-butadiene-styrene)-modified asphalt is widely used. However, there is no mature method for restoring aged SBS-modified asphalt. This study proposes the use of SBR(polymerized styrene butadiene rubber) and bio-oil for the restoration of aged SBS. In this study, five kinds of recycled asphalt were prepared by adding 5% bio-oil, 10% bio-oil, 6% SBR, 6% SBR + 5% bio-oil, and 6% SBR + 10% bio-oil to long-term aged SBS-modified asphalt. Softening point, penetration, and rotational viscosity experiments were tested to evaluate the conventional properties. Rheological tests revealed the performance of asphalt. Fourier transform infrared spectroscopy (FTIR), and atomic force microscope (AFM) tests were tested to demonstrate the microscopic characteristics of asphalt. Conventional tests investigated that aged asphalt viscosity will increase. Bio-oil could well recycle the asphalt viscosity. SBR could also soften aged asphalt, but its modification effect is limited compared with bio-oil. Rheological tests presented that the SBR and bio-oil have little impact on the temperature sensitivity of SBS-modified asphalt. SBR and bio-oil could decrease the asphalt stiffness. However, SBR and bio-oil could ameliorate the anti-cracking behavior of aged asphalt. The microscopic tests exhibited that SBR and bio-oil could decrease the asphaltene and colloid. Meanwhile, bio-oil could supplement alcohols and ethers at wave number 1000 cm-1-1270 cm-1. Alcohols and ethers are hard to oxidize, something which has a beneficial role in the anti-aged of recycled asphalt.

5.
Materials (Basel) ; 15(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36234145

RESUMO

An increasing amount of waste seashells in China has caused serious environmental pollution and resource waste. This paper aims to solve these problems by using waste seashells as modified materials to prepare high-performance modified asphalt. In this study, seashell powder (SP) and stratum corneum-exfoliated seashell powder (SCESP) were adopted to prepare 10%, 20% and 30% of seashell powder-modified asphalt (SPMA) and stratum corneum-exfoliated seashell powder-modified asphalt (SCESPMA) by the high-speed shear apparatus, respectively. The appearance and composition of two kinds of SPs were observed and determined by the scanning electron microscope (SEM). The types of functional groups, temperature frequency characteristics, low temperature performance and adhesion of SPMA were tested by the Fourier-transform infrared (FTIR) spectrometer, dynamic shear rheometer (DSR), bending beam rheometer (BBR) and contact angle meter. The results show that the SP and SCESP are rough and porous, and their main component is CaCO3, which is physically miscible to asphalt. When the loading frequency ranges from 0.1 Hz to 10 Hz, the complex shear modulus (G*) and phase angle (δ) of SPMA and SCESPMA increase and decrease, respectively. At the same load frequency, SCESPMA has a larger G* and a smaller δ than SPMA. At the same temperature, SCESPMA has a larger rutting factor (G*/sin δ) and better high-temperature deformation resistance than SPMA. SP and SCESP reduce the low-temperature cracking resistance of asphalt, of which SCESP has a more adverse effect on the low-temperature performance of asphalt than SP. When SP and SCESP are mixed with asphalt, the cohesion work (Waa), adhesion work (Was) and comprehensive evaluation parameters of water stability (ER1, ER2 and ER3) of asphalt are improved. It is shown that both SP and SCESP have good water damage resistance, of which SCESP has better water damage resistance than SP. These research results have important reference value for the application of waste biological materials in asphalt pavement.

6.
Appl Opt ; 61(25): 7401-7408, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256041

RESUMO

Streak tube imaging lidar (STIL) can obtain 4-D images of a target, and its performance is mainly determined by the streak tube sensor. To obtain a large field of view, we developed a streak tube with a photocathode length as large as 35.3 mm, which is larger than the commonly used ST-HDR (30 mm). At the same time, the temporal resolution and dynamic spatial resolution are 60 ps and 12 lp/mm, which are very suitable to obtain accurate target coordinates for 4-D imaging. In addition, the streak tube has a high detection sensitivity of 46 mA/W at 500 nm and, hence, prospects in remote imaging. To test the performance of the streak tube, an underwater STIL experiment was conducted. Echo signal processing was performed by means of a bandpass filter and a matched filter, and then the peak detection algorithm was used to reconstruct the image. The results indicate that a spatial resolution better than 9 mm is achieved in the limpid water with a depth of 20 m, and a range accuracy of 1 cm is achieved in the turbid water with a depth of 10 m. Such a performance suggests that the large-field streak tube is of great potential for underwater target imaging and other remote imaging applications.


Assuntos
Algoritmos , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Processamento de Sinais Assistido por Computador , Água
7.
PLoS One ; 17(8): e0271441, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35960754

RESUMO

Compressed fluorescence lifetime imaging (Compressed-FLIM) is a novel Snapshot compressive imaging (SCI) method for single-shot widefield FLIM. This approach has the advantages of high temporal resolution and deep frame sequences, allowing for the analysis of FLIM signals that follow complex decay models. However, the precision of Compressed-FLIM is limited by reconstruction algorithms. To improve the reconstruction accuracy of Compressed-FLIM in dealing with large-scale FLIM problem, we developed a more effective combined prior model 3DTGp V_net, based on the Plug and Play (PnP) framework. Extensive numerical simulations indicate the proposed method eliminates reconstruction artifacts caused by the Deep denoiser networks. Moreover, it improves the reconstructed accuracy by around 4dB (peak signal-to-noise ratio; PSNR) over the state-of-the-art TV+FFDNet in test data sets. We conducted the single-shot FLIM experiment with different Rhodamine reagents and the results show that in practice, the proposed algorithm has promising reconstruction performance and more negligible lifetime bias.


Assuntos
Artefatos , Compressão de Dados , Algoritmos , Compressão de Dados/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagem Óptica , Razão Sinal-Ruído
8.
RSC Adv ; 12(26): 16798-16804, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35754908

RESUMO

As one of Earth's most widely distributed and abundant elements, iron impacts the natural environment and biological systems. Therefore, developing a simple, rapid, and accurate Fe3+ detection method is vital. Fluorescent dicarboxylic cellulose nanocrystals (FDCN) with selective quenching of Fe3+ were synthesized using 7-amino-4-methylcoumarin (AMC), and dicarboxylic cellulose nanocrystals (DCN) prepared by sequential periodate-chlorite oxidation. The sensing characteristics and detection mechanism of FDCN for Fe3+ were studied by fluorescence spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), the Stern-Volmer equation, Job's plot method, and the Benesi-Hildebrand equation. The results showed that FDCN was highly selective for Fe3+, and other metal ions did not reduce the selectivity. High sensitivity with a detection limit of 0.26 µM and a Stern-Volmer quenching constant of 0.1229 were also achieved. The coordination between Fe3+ and the carboxylic, hydroxyl, and amide groups on the surface of FDCN and the carbonyl of coumarin lactones to form FDCN/Fe3+ complexes prevented the intramolecular charge transfer (ICT) process and led to the fluorescence quenching of FDCN. EDTA restored the fluorescence emission of quenched FDCN. The complexation stoichiometry of Fe3+ to FDCN was 1 : 1, and the association constant was 3.23 × 104 M-1. The high hydrophilicity, sensitivity, and selectivity of FDCN for Fe3+ make the chemosensor suitable for Fe3+ trace detection in drinking water and biology.

9.
RSC Adv ; 11(40): 24694-24701, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35481032

RESUMO

High-performance fluorescent composites are key to the development and improvement of fluorescent molecular probe technology. In this study, cellulose nanocrystals (CNC) with high carboxyl concentrations were prepared via sequential periodate-chlorite oxidation. Then, fluorescent cellulose nanocrystals (FCNC) were prepared by attaching 7-amino-4-methylcoumarin (AMC) onto CNC under 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) catalysis. The morphology and fluorescence properties of FCNC were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, elemental analysis, ultraviolet-visible absorbance, fluorescence spectrophotometry, and fluorescence spectroscopy. The results showed that AMC was grafted onto the CNC surface by an amidation reaction, and the absorption and emission maxima for FCNC were blue-shifted from 350 nm and 445 nm of AMC to 335 nm and 440 nm, respectively. FCNC retained the crystallinity and nano-topography size of the CNC. The fluorescence intensity, quantum yield, and fluorescence lifetime of FCNC showed the same change law; it first increased and then decreased with an increase in the graft density of AMC from 0.201 to 0.453 AMC molecules per nm2. The FCNC prepared in this study have good optical properties and can be used in the fields of fluorescent molecular probes and biological imaging.

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