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1.
Langmuir ; 36(33): 9818-9826, 2020 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-32787038

RESUMEN

Anisotropic nanoparticles and their dispersions have attracted much attention because of their distinguished characteristics and promising applications. In this study, the novel liquid crystalline nanocomposite ionogel electrolyte materials based on anisotropic nanoparticles of attapulgite (ATP) have been prepared. The gelation, liquid crystalline (LC) behavior, thermal stability, and ionic conductivity were systematically investigated. Rheological, polarized optical microscopy (POM), and small-angle X-ray scattering (SAXS) measurements demonstrated that these liquid crystalline ionogels showed a two-step mechanism consisting of gelation and subsequent reorganization of the gel. Interestingly, the obtained ionogel electrolytes were very stable and LC gel structures were not destroyed even though the temperature was as high as 200 °C. Furthermore, these ionogels possessed outstanding thermal stability and the decomposition temperature exceeded 400 °C. Remarkably, the LC nanocomposite ionogel electrolytes exhibited high room temperature ionic conductivity and the value still exceeded 1.0 × 10-3 S/cm even when the ATP concentration up to 30 wt %. These novel findings are very useful for the fabrication of high temperature resistant electrochemical devices and liquid crystalline nanocomposite materials.

2.
Opt Express ; 25(8): A323-A337, 2017 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-28437919

RESUMEN

Absorption and scattering by molecules, aerosols and hydrosols, and the reflection and transmission over the sea surface can modify the original polarization state of sunlight. However, water-leaving radiance polarization, containing embedded water constituent information, has largely been neglected. Here, the efficiency of the parallel polarization radiance (PPR) for enhancing ocean color signal of suspended particulate matter is examined via vector radiative transfer simulations and laboratory experiments. The simulation results demonstrate that the PPR has a slightly higher ocean color signal at the top-of-atmosphere as compared with that of the total radiance. Moreover, both the simulations and laboratory measurements reveal that, compared with total radiance, PPR can effectively enhance the normalized ocean color signal for a large range of observation geometries, wavelengths, and suspended particle concentrations. Thus, PPR has great potential for improving the ocean color signal detection from satellite.

3.
Macromol Rapid Commun ; 38(21)2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28898505

RESUMEN

This study reports a remarkably facile method to synthesize novel ionogels with imidazolium cycle crosslinks based on polyamidoamine (PAMAM) dendrimers via one-pot, modified Debus-Radziszewski reaction in ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM][OAc]). High room temperature ionic conductivity (up to 6.8 mS cm-1 ) is achieved, and more remarkably, it can still exceed 1 mS cm-1 when the dendrimer content reached 70% because PAMAM dendrimers are completely amorphous with many cavities and the newly formed imidazolium crosslinks contains ions. The elastic modulus of these ionogels can exceed 106 Pa due to the newly-formed rigid imidazolium crosslinks. Crucially, these ionogels are robust gels even at temperatures up to 160 °C. Such novel ionogels with high ionic conductivity, tunable modulus, and flexibility are desirable for use in high-temperature flexible electrochemical devices.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Dendrímeros/química , Geles/síntesis química , Imidazoles/química , Líquidos Iónicos/química , Elasticidad , Conductividad Eléctrica , Geles/química , Temperatura , Viscosidad
4.
IEEE Trans Pattern Anal Mach Intell ; 46(5): 3438-3449, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38109233

RESUMEN

Shadow detection is a basic task of remote sensing image analysis, but it is often seriously disturbed by vegetation, water bodies, and black objects. It is observed that vegetation and dark objects often show a dark look in visible bands but brighter in the near-infrared (NIR), and is also noticed that the reflection of inland water bodies in the green band is stronger than that in the blue band. Taking advantage of these physical properties and combining them with the bluish and dark appearance of shadows, we propose a simple but effective shadow detection method for multispectral remote sensing images. These physical properties are used to create transformation models that suppress features such as vegetation, water bodies, etc., but at the same time enhance shadows. Then, we transform the shadow representation into a color space to generate candidate shadows using dominant color components. To separate shadows from the others, we propose two indexes, the normalized Color Difference Composite Index (CDCI) and Color Purity Index (CPI), and fuse them to achieve shadows and their confidence. The experimental results indicate that the proposed method can effectively detect the shadows in multispectral images and outperforms the state-of-the-art approaches.

5.
World J Gastrointest Surg ; 16(6): 1647-1659, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38983313

RESUMEN

BACKGROUND: The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are novel inflammatory indicators that can be used to predict the severity and prognosis of various diseases. We categorize acute pancreatitis by etiology into acute biliary pancreatitis (ABP) and hypertriglyceridemia-induced acute pancreatitis (HTGP). AIM: To investigate the clinical significance of NLR and PLR in assessing persistent organ failure (POF) in HTGP and ABP. METHODS: A total of 1450 patients diagnosed with acute pancreatitis (AP) for the first time at Shanxi Bethune Hospital between January 2012 and January 2023 were enrolled. The patients were categorized into two groups according to the etiology of AP: ABP in 530 patients and HTGP in 241 patients. We collected and compared the clinical data of the patients, including NLR, PLR, and AP prognostic scoring systems, within 48 h of hospital admission. RESULTS: The NLR (9.1 vs 6.9, P < 0.001) and PLR (203.1 vs 160.5, P < 0.001) were significantly higher in the ABP group than in the HTGP group. In the HTGP group, both NLR and PLR were significantly increased in patients with severe AP and those with a SOFA score ≥ 3. Likewise, in the ABP group, NLR and PLR were significantly elevated in patients with severe AP, modified computed tomography severity index score ≥ 4, Japanese Severity Score ≥ 3, and modified Marshall score ≥ 2. Moreover, NLR and PLR showed predictive value for the development of POF in both the ABP and HTGP groups. CONCLUSION: NLR and PLR vary between ABP and HTGP, are strongly associated with AP prognostic scoring systems, and have predictive potential for the occurrence of POF in both ABP and HTGP.

6.
J Inflamm Res ; 17: 6673-6690, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39345896

RESUMEN

Objective: To analyze the influence of diabetes mellitus on the clinical outcomes of moderately severe acute pancreatitis (MSAP) and severe acute pancreatitis (SAP). Methods: This retrospective study included patients diagnosed with MSAP and SAP at Shanxi Bethune Hospital from January 1, 2017, to December 31, 2021. Clinical data were collected, including patient demographics, 24-hour laboratory indicators, and inflammation indices. Propensity score matching (PSM) was used to compare outcomes before and after matching. Patients were randomized into training and validation sets (7:3) to develop and validate a clinical prediction model for infected pancreatic necrosis (IPN). Results: Among 421 patients, 79 had diabetes at admission. Before PSM, diabetic patients had higher incidences of peripancreatic fluid (71% vs 47%, p<0.001) and IPN (48% vs 10%, p<0.001), higher surgical intervention rates (24% vs 12%, p=0.008), and significant differences in abdominocentesis (22% vs 11%, p=0.014). After PSM, 174 patients were matched, and the diabetes group still showed higher incidences of peripancreatic fluid (69% vs 47%, p=0.008), IPN (48% vs 11%, p<0.001), and surgical intervention rates (27% vs 13%, p=0.037). Diabetes, modified CT severity index (MCTSI), serum calcium, and HDL-c were identified as independent risk factors for IPN. The prediction model demonstrated good predictive value. Conclusion: In MSAP and SAP patients, diabetes mellitus can exert an influence on their clinical outcome and is an independent risk factor for IPN. The alignment diagram and web calculator constructed on the basis of diabetes mellitus, modified CT severity index (MCTSI), serum calcium and high-density lipoprotein cholesterol (HDL-c) have good predictive value and clinical guidance for the occurrence of IPN in MSAP and SAP.

7.
Water Res ; 251: 121100, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38198974

RESUMEN

Studies on the Fe(VI)/S(IV) process have focused on improving the efficiency of emerging contaminants (ECs) degradation under alkaline conditions. However, the performance and mechanisms under varying pH levels remain insufficiently investigated. This tudy delved into the efficiency and mechanism of Fe(VI)/S(IV) process using sulfamethoxazole (SMX) and ibuprofen (IBU) as model contaminants. We found that pH was crucial in governing the generation of reactive species, and both Fe(V/IV) and SO4•- were identified in the reaction system. Specifically, an increase in pH favored the formation of SO4•-, while the formation of Fe(VI) to Fe(V/IV) became more significant at lower pH. At pH 3.2, Fe(III) resulting from the Fe(VI) self-decay reactedwith HSO3-to produce SO4•-and •OH. Under near-neutral conditions, the coexistance of Fe(V/IV) and SO4•- in abundance contributed to the optimal oxidation of both pollutants in the Fe(VI)/S(IV) process, with the removal exceeding 74% in 5 min. Competitive quenching experiments showed that the contributions of Fe(V/IV) to SMX and IBU destruction dimished, while the contributions of radicals increased with an increase in pH. However, this evolution was slower during SMX degradation compared to IBU degradation. A comprehensive understnding of pH as the key factor is essential for the optimization of the sulfite-activated Fe(VI) oxidation process in water treatment.


Asunto(s)
Hierro , Contaminantes Químicos del Agua , Purificación del Agua , Compuestos Férricos , Contaminantes Químicos del Agua/análisis , Cinética , Oxidación-Reducción , Sulfametoxazol , Purificación del Agua/métodos , Ibuprofeno
8.
Health Place ; 81: 103018, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36996594

RESUMEN

Few studies have investigated relative contributions of the built and natural environments to and their nonlinear associations with leisure physical activity (PA) in different spatial contexts. Applying gradient boosting decision tree models to data comprising 1049 adults collected in Shanghai, we investigated the associations between built and natural environments and leisure PA in residential and workplace neighborhoods. Results show that the built environment is more important than the natural environment to leisure PA in both residences and workplaces. Environmental attributes have nonlinear and threshold effects. Within certain ranges, land use mix and population density have opposite associations with leisure PA in residences and workplaces, whereas the distance to the city center and the area of water are associated with leisure PA in residences and workplaces with the same direction. These findings help urban planners design context-specific environmental interventions for supporting leisure PA.


Asunto(s)
Planificación Ambiental , Lugar de Trabajo , Adulto , Humanos , China , Características de la Residencia , Actividades Recreativas , Ejercicio Físico , Caminata
9.
Water Res ; 228(Pt B): 119363, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36434974

RESUMEN

Application of heterogeneous advanced oxidation processes (AOPs) for wastewater treatment suffers from the low oxidant utilization efficiency, slow catalytic cycling and severe matrix interference. Herein, we report that amorphous zirconium dioxide (aZrO2), a redox-inert metal oxide, can efficiently activate peroxymonosulfate (PMS) to degrade organic micropollutants under very low oxidant doses and complex coexisting matrices. Distinct from conventional AOPs where radicals are formed, the surface Zr(IV)-PMS* complex was identified as the principal reactive species, and primarily conducted oxygen-atom-transfer route with selected molecules. Quantitative structure-activity relationship analysis indicated that the formation of Zr(IV)-PMS* complex was governed by the density of the surface hydroxyl groups. The strong interaction between the Zr atom and PMS caused the deviation of the negative charge from Zr(IV) metal sites to the oxidant. As a result, the O-O bond of the adsorbed PMS was prolonged and its oxidation potential elevated, which enabled it to directly react with contaminants. This study indicates the potential of aZrO2 as a novel and eco-friendly catalyst that activates PMS to selectively tackle organic contaminants, and sheds light on the designing of Fenton-like catalysts using redox-inert metals.


Asunto(s)
Compuestos Orgánicos , Peróxidos , Oxidantes , Relación Estructura-Actividad Cuantitativa
10.
ACS Appl Mater Interfaces ; 13(4): 5614-5624, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33492940

RESUMEN

Stretchable ionogels have recently emerged as promising soft and safe ionic conductive materials for use in wearable and stretchable electrochemical devices. However, the complex preparation process and insufficient thermomechanical stability greatly limit the precise rapid fabrication and application of stretchable ionogels. Here, we report an in situ 3D printing method for fabricating high-performance single network chemical ionogels as advanced strain sensors. The ionogels consist of a special cross-linking network constructed by poly(ionic liquid) and hyperbranched polymer (macro-cross-linkers) that exhibits high stretchability (>1000%), superior room-temperature ionic conductivity (up to 5.8 mS/cm), and excellent thermomechanical stability (-75 to 250 °C). The strain sensors based on ionogels have a low response time (200 ms), high sensitivity with temperature independence, long-term durability (2000 cycles), and excellent temperature tolerance (-60 to 250 °C) and can be used as human motion sensors. This work provides a new strategy to design highly stretchable and superior stable electronic devices.

11.
Nanoscale ; 11(8): 3689-3700, 2019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-30742194

RESUMEN

A novel type of chemically crosslinked liquid crystalline nanocomposite ionogel electrolyte based on poly(ionic liquid) (PIL) with superior ionic conductivity and high anisotropic conductivity was designed and synthesized using the in situ photopolymerization of sheared soft ionogels containing charged halloysite nanotubes (HNTs) and ionic liquid monomers. The oriented structure was investigated using scanning electron microscopy (SEM) and small-angle X-ray scattering (SAXS). The chemically crosslinked backbone of the PIL and the addition of HNTs endowed the flexible ionogels with a combined very high modulus (up to 26.7 MPa) and mechanical strength (up to 4.4 MPa). Crucially, the obtained ionogels exhibited high mechanical stability even at temperatures up to 200 °C. Remarkably, in terms of the conductivities, the resulting pre-sheared ionogels displayed superior room temperature ionic conductivity (up to 6 mS cm-1) and a very high conductivity anisotropy ratio (up to 1600), owing to the alignment of the HNTs with oppositely charged surfaces and the high ionic conductivity of the polyelectrolyte PILs. Furthermore, flexible solid-state supercapacitor devices based on the high ion-conductive nanocomposite ionogels were fabricated, which demonstrated high and temperature-dependent specific capacitance, and remarkable cycling stability and flexible performance.

12.
Polymers (Basel) ; 11(3)2019 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-30960428

RESUMEN

A new family of chemical cross-linked ionogel is successfully synthesized by photopolymerization of hyperbranched aliphatic polyester with acrylate terminal groups in an ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4). The microstructure, viscoelastic behavior, mechanical property thermal stability, and ionic conductivities of the ionogels are investigated systematically. The ionogels exhibit high mechanical strength (up to 1.6 MPa) and high mechanical stability even at temperatures up to 200 °C. It is found to be thermally stable up to 371.3 °C and electrochemically stable above 4.3 V. The obtained ionogels show superior ionic conductivity over a wide temperature range (from 1.2 × 10-3 S cm-1 at 20 °C up to 5.0 × 10-2 S cm-1 at 120 °C). Moreover, the Li/LiFePO4 batteries based on ionogel electrolyte with LiBF4 show a higher specific capacity of 153.1 mAhg-1 and retain 98.1% after 100 cycles, exhibiting very stable charge/discharge behavior with good cycle performance. This work provides a new method for fabrication of novel advanced gel polymer electrolytes for applications in lithium-ion batteries.

13.
ACS Appl Mater Interfaces ; 10(28): 24149-24156, 2018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-29956538

RESUMEN

It has been a big challenge to separate oil slicks from oil-polluted water sources efficiently and in an environmentally friendly way. Three-dimensional (3D) hydrophobic and superoleophilic materials have great potential in water separation continually. In this study, we developed a facile two-step strategy for fixing functionalized nanoparticles on 3D complex macroscopic surfaces. By using commercial glue to immobilize different types of nanoparticles on the surfaces of various 3D objects, superhydrophobic copper foam, cotton wool, and polyurethane (PU) sponge with strong stability and excellent performance were prepared. Owing to flexible fixing with the glue, the prepared PU sponge remained superhydrophobic after 950 mechanical compression cycles, 250 cycles of absorption/squeezing, or soaking in n-dodecane for 60 h. The prepared PU sponge was applied to the rapid absorption of clean oil on a water surface, and the feasibility of separating mixed oil through capillary separation of cavernous bodies was examined. Furthermore, the method for loading nanoparticles onto a 3D structure can be used with many self-cleaning, flexible electrodes and catalysts.

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