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1.
Small ; 20(34): e2401216, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38593322

RESUMEN

Polarization-sensitive broadband optoelectronic detection is crucial for future sensing, imaging, and communication technologies. Narrow bandgap 2D materials, such as Te and PdSe2, show promise for these applications, yet their polarization performance is limited by inherent structural anisotropies. In this work, a self-powered, broadband photodetector utilizing a Te/PdSe2 van der Waals (vdWs) heterojunction, with orientations meticulously tailored is introduced through polarized Raman optical spectra and tensor calculations to enhance linear polarization sensitivity. The device exhibits anisotropy ratios of 1.48 at 405 nm, 3.56 at 1550 nm, and 1.62 at 4 µm, surpassing previously-reported photodetectors based on pristine Te and PdSe2. Additionally, it exhibits high responsivity (617 mA W-1 at 1550 nm), specific detectivity (5.27 × 1010 Jones), fast response (≈4.5 µs), and an extended spectral range beyond 4 µm. The findings highlight the significance of orientation-engineered heterostructures in enhancing polarization-sensitive photodetectors and advancing optoelectronic technology.

2.
Phys Chem Chem Phys ; 25(26): 17207-17213, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37350186

RESUMEN

Transition metal and nitrogen co-doped carbon materials (M-N-C) have attracted great attention in the field of catalysis due to their high atomic utilization and outstanding catalytic performance. Herein, a series of Co and N-doped carbon catalysts (Co-N-C@mSiO2-x) were successfully prepared by pyrolysis of cobalt porphyrins in situ synthesized in the cavity of mesoporous hollow silica spheres according to a ship-in-bottle method. The optimal catalyst exhibited excellent catalytic performance for the selective oxidation of ethylbenzene, with 95.5% conversion for ethylbenzene and 98.9% selectivity toward acetophenone. In combination with characterization techniques, acid treatment experiments and KSCN poisoning tests, the successful synthesis of cobalt-porphyrins in hollow silica spheres was demonstrated, and the excellent performance of Co-N-C@mSiO2-0.10 was attributed to the more acid-resistant Co-Nx species as the main metal active center. In addition, the N-containing groups could significantly facilitate the conversion of ethylbenzene. This work is expected to provide a straightforward and green approach to design metal and N co-doped carbon materials.

3.
Fish Shellfish Immunol ; 82: 453-459, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30145199

RESUMEN

The noble scallop Chlamys nobilis has been a commercially important marine cultured bivalve in the Southern Sea of China for decades. Mass mortality events, however, often occur during scallops' cultivation. Mortality of up to 67%-90% was recorded at the beginning of March in 2017 in some culture areas of Nan'ao (Shantou, China), spreading to all scallops within a week. In the present study, in order to investigate the response of the noble scallop at the physiological and molecular level during mass mortality, scallops with different mortalities of 90%, 67%, and 6% were sampled from three sites at Hunter bay, Baisha bay, and Longhai, respectively. Total carotenoids content (TCC), total antioxidant capacity (TAC), malondialdehyde (MDA) content and the expression levels of three immune-related genes (toll-like receptor, C-type lectin receptor and big defensing) in different scallop tissues were determined. The scallops were divided into three groups of sub-health, lesion, and health. TAC, TCC, as well as transcript levels of CnTLR-1, Cnlec-1 and CnBD in sub-health and lesion scallops were all significantly lower (P < 0.05) than those in health scallops, while MDA in sub-health and lesion scallops were significantly higher than those in health scallops (P < 0.05). Similarly, TCC and TAC in lesion scallops were both higher than sub-health scallops. Moreover, significantly positive correlations were found between TCC and TAC (P < 0.05) and between CnTLR-1 and Cnlec-1 (P < 0.05), while significantly negative correlations were found between TCC and CnTLR-1 (P < 0.05), TCC and Cnlec-1 (P < 0.05), TAC and CnBD (P < 0.05), as well as between MDA and Cnlec-1 (P < 0.001). All the results indicate that noble scallops significantly change their physiological and molecular levels when suffering from stress, and that their antioxidant and immune response systems play important defense functions.


Asunto(s)
3,4-Metilenodioxianfetamina/metabolismo , Antioxidantes/metabolismo , Carotenoides/metabolismo , Inmunidad Innata , Pectinidae/fisiología , Transcripción Genética/inmunología , Animales , Acuicultura , China , Pectinidae/inmunología
4.
Water Sci Technol ; 70(9): 1488-95, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25401312

RESUMEN

The growth of forecasting models has resulted in the development of an excellent model known as the support vector machine (SVM). SVMs can find a global optimal solution equipped with kernel functions. This research trains and tests the SVM network and constructs the support vector regression prediction model by using hydrologic data. Six hydrologic time series were calculated by different kernel functions (namely, linear, polynomial, radial basis function (RBF)), to determine which kernel is the more suitable hydrologic time series in practice. A new solution is presented to identify the good parameter (C; g) by using grid-search and cross-validation. Results prove that linear SVM is a superior model to polynomial and RBF and produced the most accurate results for modeling hydrologic time series behavior as complex hydrologic phenomena. The case study also shows that the calculation errors were correlated with data characteristics. More stable raw data will result in a more accurate result, whereas more random data will result in a more inaccurate result. Model performance could also be dependent on base data nonlinearity.


Asunto(s)
Monitoreo del Ambiente/métodos , Lagos/análisis , Máquina de Vectores de Soporte , Algoritmos , China , Predicción , Modelos Teóricos , Programas Informáticos
5.
Nanoscale ; 16(37): 17426-17432, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39206958

RESUMEN

Enhancing the exposure of metal active sites and maximizing metal atom utilization are critical challenges in heterogeneous catalysis. To solve these issues, heterogeneous catalysts are usually activated by chemicals. Herein, potassium chloride (KCl) was used as an activator to prepare cobalt-nitrogen co-doped (Co-Nx) hollow periodic mesoporous organosilica spheres (Co-Nx/HPMOs-KCl). Co-Nx/HPMOs-KCl showed outstanding catalytic activity for the selective oxidation of ethylbenzene to acetophenone, with a conversion of up to 94.0% for ethylbenzene and a high selectivity of 98.4% towards acetophenone. Additionally, Co-Nx/HPMOs-KCl maintained excellent catalytic performance for the oxidation of ethylbenzene after six cycles. The excellent performance of Co-Nx/HPMOs-KCl was attributed to the activation of KCl, which increased the specific surface area of the catalyst and thus facilitated the exposure of more metal active sites. After the removal of unstable metal species through further acid treatment, the remaining metal active sites were thus fully exposed and stably embedded in the framework of the hollow periodic mesoporous organosilica spheres (HMPOs). This work presents an efficient catalyst and offers new insights for the improvement of heterogeneous catalysts.

6.
Water Res ; 249: 121007, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38096726

RESUMEN

Polybrominated diphenyl ethers (PBDEs) serve as brominated flame retardants which continue to receive considerable attention because of their persistence, bioaccumulation, and potential toxicity. Although PBDEs have been restricted and phased out, large amounts of commercial products containing PBDEs are still in use and discarded annually. Consequently, PBDEs added to products can be released into our surrounding environments, particularly in aquatic systems, thus posing great risks to human health. Many studies and reviews have described the possible toxic effects of PBDEs, while few studies have comprehensively summarized and analyzed the global trends of their toxicity assessment. Therefore, this study utilizes bibliometrics to evaluate the worldwide scientific output of PBDE toxicity and analyze the hotspots and future trends of this field. Firstly, the basic information including the most contributing countries/institutions, journals, co-citations, influential authors, and keywords involved in PBDE toxicity assessment will be visualized. Subsequently, the potential toxicity of PBDE exposure to diverse systems, such as endocrine, reproductive, neural, and gastrointestinal tract systems, and related toxic mechanisms will be discussed. Finally, we conclude this review by outlining the current challenges and future perspectives in environmentally relevant PBDE exposure, potential carriers for PBDE transport, the fate of PBDEs in the environment and human bodies, advanced stem cell-derived organoid models for toxicity assessment, and promising omics technologies for obtaining toxic mechanisms. This review is expected to offer systematical insights into PBDE toxicity assessments and facilitate the development of PBDE-based research.


Asunto(s)
Retardadores de Llama , Éteres Difenilos Halogenados , Humanos , Éteres Difenilos Halogenados/toxicidad , Retardadores de Llama/toxicidad
7.
World J Clin Cases ; 12(20): 4272-4288, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39015929

RESUMEN

BACKGROUND: Education, cognition, and intelligence are associated with cholelithiasis occurrence, yet which one has a prominent effect on cholelithiasis and which cardiometabolic risk factors mediate the causal relationship remain unelucidated. AIM: To explore the causal associations between education, cognition, and intelligence and cholelithiasis, and the cardiometabolic risk factors that mediate the associations. METHODS: Applying genome-wide association study summary statistics of primarily European individuals, we utilized two-sample multivariable Mendelian randomization to estimate the independent effects of education, intelligence, and cognition on cholelithiasis and cholecystitis (FinnGen study, 37041 and 11632 patients, respectively; n = 486484 participants) and performed two-step Mendelian randomization to evaluate 21 potential mediators and their mediating effects on the relationships between each exposure and cholelithiasis. RESULTS: Inverse variance weighted Mendelian randomization results from the FinnGen consortium showed that genetically higher education, cognition, or intelligence were not independently associated with cholelithiasis and cholecystitis; when adjusted for cholelithiasis, higher education still presented an inverse effect on cholecystitis [odds ratio: 0.292 (95%CI: 0.171-0.501)], which could not be induced by cognition or intelligence. Five out of 21 cardiometabolic risk factors were perceived as mediators of the association between education and cholelithiasis, including body mass index (20.84%), body fat percentage (40.3%), waist circumference (44.4%), waist-to-hip ratio (32.9%), and time spent watching television (41.6%), while time spent watching television was also a mediator from cognition (20.4%) and intelligence to cholelithiasis (28.4%). All results were robust to sensitivity analyses. CONCLUSION: Education, cognition, and intelligence all play crucial roles in the development of cholelithiasis, and several cardiometabolic mediators have been identified for prevention of cholelithiasis due to defects in each exposure.

8.
J Phys Chem Lett ; 15(19): 5103-5111, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38708945

RESUMEN

The vast compositional space available in high-entropy oxide semiconductors offers unique opportunities for electronic band structure engineering in an unprecedented large room. In this work, with wide band gap semiconductor lithium niobate (LiNbO3) as a model system, we show that the substitutional addition of high-entropy metal cation mixtures within the Nb sublattice can lead to the formation of a single-phase solid solution featuring a substantially narrowed band gap and intense broadband visible light absorption. The resulting high-entropy LiNbO3 [denoted as Li(HE)O3] crystallizes as well-faceted nanocubes; atomic-resolution imaging and elemental mapping via transmission electron microscopy unveil a distinct local chemical complexity and lattice distortion, characteristics of high-entropy stabilized solid solution phases. Because of the presence of high-entropy stabilized Co2+ dopants that serve as active catalytic sites, Li(HE)O3 nanocubes can accomplish the visible light-driven photocatalytic water splitting in an aqueous solution containing methanol as a sacrificial electron donor without the need of any additional co-catalysts.

9.
Chemosphere ; 351: 141185, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38215831

RESUMEN

Chromium-containing wastewater causes serious environmental pollution due to the harmfulness of Cr(VI). The ferrite process is typically used to treat chromium-containing wastewater and recycle the valuable chromium metal. However, the current ferrite process is unable to fully transform Cr(VI) into chromium ferrite under mild reaction conditions. This paper proposes a novel ferrite process to treat chromium-containing wastewater and recover valuable chromium metal. The process combines FeSO4 reduction and hydrothermal treatment to remove Cr(VI) and form chromium ferrite composites. The Cr(VI) concentration in the wastewater was reduced from 1040 mg L-1 to 0.035 mg L-1, and the Cr(VI) leaching toxicity of the precipitate was 0.21 mg L-1 under optimal hydrothermal conditions. The precipitate consisted of micron-sized ferrochromium spinel multiphase with polyhedral structure. The mechanism of Cr(VI) removal involved three steps: 1) partial oxidation of FeSO4 to Fe(III) hydroxide and oxy-hydroxide; 2) reduction of Cr(VI) by FeSO4 to Cr(III) and Fe(III) precipitates; 3) transformation and growth of the precipitates into chromium ferrite composites. This process meets the release standards of industrial wastewater and hazardous waste and can improve the efficiency of the ferrite process for toxic heavy metal removal.


Asunto(s)
Óxido de Aluminio , Aleaciones de Cromo , Óxido de Magnesio , Aguas Residuales , Contaminantes Químicos del Agua , Compuestos Férricos/química , Cromo/química , Hidróxidos , Contaminantes Químicos del Agua/análisis
10.
Eur J Pharmacol ; 942: 175520, 2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36693551

RESUMEN

Sepsis comprises a lethal immunologic response due to infection. Increasingly, evidence has demonstrated the important role of long non-coding RNA growth arrest-specific transcript 5 (GAS5) in the regulation of sepsis. Nevertheless, the mechanisms by which GAS5 participates in the progression of sepsis remain unclear. Our study demonstrated the role and underlying mechanism of GAS5 in regulating lipopolysaccharide (LPS)-induced inflammation. In this study, GAS5 expression was found to be markedly decreased in serum samples of sepsis patients and a sepsis mouse model, and was negatively related with HMGB1 expression. GAS5 overexpression inhibited cell inflammatory responses by decreasing HMGB1 release. Furthermore, GAS5 inhibited LPS-mediated hyperacetylation and the release of HMGB1 by increasing the expression of sirtuin1 (SIRT1). Additionally, upregulated GAS5 attenuated inflammatory responses in vitro and vivo, and the knockdown of a miR-155-5p mimic and SIRT1 rescued the effects of GAS5 upregulation. Mechanistically, GAS5 sponged miR-155-5p to upregulate SIRT1, thereby inhibiting HMGB1 acetylation and release. In conclusion, our findings indicate that GAS5 suppresses inflammatory responses by modulating the miR-155-5p/SIRT1/HMGB1 axis in sepsis, providing a novel therapeutic target for inflammation in sepsis.


Asunto(s)
Proteína HMGB1 , MicroARNs , ARN Largo no Codificante , Sepsis , Animales , Ratones , Apoptosis/genética , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Inflamación/genética , Lipopolisacáridos/farmacología , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Sepsis/genética , Sirtuina 1/genética , Sirtuina 1/metabolismo
11.
Burns Trauma ; 11: tkad023, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38026444

RESUMEN

Background: Sepsis is a common severe complication in major burn victims and is characterized by a dysregulated systemic response to inflammation. YTH domain family 2 (YTHDF2), a well-studied N6-methyladenosine (m6A) reader that specifically recognizes and binds to m6A-modified transcripts to mediate their degradation, is connected to pathogenic and physiological processes in eukaryotes, but its effect on sepsis is still unknown. We aimed to discover the effects and mechanisms of YTHDF2 in sepsis. Methods: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blot analyses were used to measure the expression of YTHDF2, the interleukin 6 receptor (IL-6R), high-mobility group box-1 (HMGB1), Janus kinase 2 (JAK2) and signal transducer and activator of transcription 1 (STAT1) under different in vitro conditions. Enzyme-linked immunosorbent assays were utilized to evaluate the expression of HMGB1, IL-6, IL-1ß and tumor necrosis factor-α. To confirm that YTHDF2 specifically targets IL-6R mRNA, RNA immunoprecipitation and dual-luciferase reporter assays were performed. Finally, we utilized a mouse model of lipopolysaccharide (LPS)-induced sepsis to verify the effects of YTHDF2 in vivo. Results: According to our findings, YTHDF2 was expressed at a low level in peripheral blood mononuclear cells from septic mice and patients as well as in LPS-induced RAW264.7 cells. Overexpression of YTHDF2 alleviated the inflammatory response by inhibiting HMGB1 release and JAK2/STAT1 signalling in LPS-stimulated cells. Mechanistically, YTHDF2 suppressed JAK2/STAT1 signalling by directly recognizing the m6A-modified site in IL-6R and decreasing the stability of IL-6R mRNA, thereby inhibiting HMGB1 release. In vivo experiments showed that YTHDF2 played a protective role in septic mice by suppressing the IL-6R/JAK2/STAT1/HMGB1 axis. Conclusions: In summary, these findings demonstrate that YTHDF2 plays an essential role as an inhibitor of inflammation to reduce the release of HMGB1 by inhibiting the IL-6R/JAK2/STAT1 pathway, indicating that YTHDF2 is a novel target for therapeutic interventions in sepsis.

12.
Sci Total Environ ; 813: 152637, 2022 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-34963612

RESUMEN

Chromite ore processing residue (COPR) has been a severe environmental contaminant which is worthy of attention. In this study, we developed an eco-friendly and practical technology for effectively stabilizing and recovering Cr(VI) in COPR via combining FeSO4 reducing agent and the hydrothermal treatment. A stable spinel phase product was formed during detoxification. In addition, the ferrochrome resources in the treated COPR can be obtained by magnetic separation. As we studied, the hydrothermal environment promoted the release of unstable Na2CrO4 from COPR into the solution, and the released CrO42- was reduced to Cr(III) by FeSO4. Subsequently, Cr(III), Fe(II) and Fe(III) were hydrothermally mineralized to form the magnetic spinel phase Fe2+(Cr3+X, Fe3+2-x)O4 (FeCr spinel substance), which was conducive to the magnetic separation of ferrochrome resources. Under the optimal hydrothermal conditions (0.15 g FeSO4/2 g COPR, treatment at 180 °C for 8 h), the total Cr leaching concentration of treated COPR (COPR-HT) was decreased from 120.51 mg L-1 to 0.23 mg L-1, well below the regulatory limit of 1.5 mg L-1 (HJ/T 301-2007, China EPA). After 300 days aging under atmospheric conditions, the total Cr leaching concentration of COPR-HT was still below 1.5 mg L-1. Besides, the COPR-HT after magnetic separation contained 11.52 wt% Cr2O3 and 53.44 wt% Fe2O3, which can be used as the raw material for steel industry. The underlying mechanism of COPR stabilization was explained by XRD, XPS and SEM-EDS analysis. This work converted the toxic and unstable Cr(VI) in COPR into the long-term stable FeCr spinel substance that is easy to magnetically separate. It has important reference for the harmless disposal and resource utilization of other chromium-containing hazardous wastes including chromium slag and electroplating sludge.


Asunto(s)
Cromo , Compuestos Férricos , Óxido de Aluminio , Cromo/análisis , Residuos Industriales/análisis , Óxido de Magnesio , Fenómenos Magnéticos
13.
J Hazard Mater ; 440: 129754, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35985215

RESUMEN

Chromium ore processing residue (COPR) is a hazardous waste generated during the production of chromate. Currently, approximately 10% of Cr2O3 cannot be extracted after chromite sodium roasting and remains in COPR, wasting valuable Cr resources. In this study, Mg was selectively removed by using (NH4)2SO4 roasting in combination with H2SO4 leaching. The results showed that the selective removal of 79.55% Mg from COPR could be achieved under the optimum (NH4)2SO4 roasting conditions (80 mmol (NH4)2SO4, 800 °C, 2 h). During the subsequent sodium roasting and acid leaching stages, the Cr extraction rate was 84.63% for the COPR direct roasting and 95.39% for the Mg removal residue roasting. The increased Cr extraction efficiency is attributed to the transformation of Mg-rich spinel and diopside (the Mg & Cr coexisting phases) in COPR converted into easily extractable (Fe,Cr)2O3 and Cr2O3 after the Mg treatment. This study investigated that the phase transformation of the Cr host phases is crucial for the sufficient extraction of Cr and provides inspiration for the development of efficient and practical Cr extraction techniques. Moreover, the method can be extended to the effective extraction of Cr from other Cr-containing wastes.


Asunto(s)
Cromatos , Residuos Industriales , Cromo/química , Residuos Peligrosos , Residuos Industriales/análisis , Sodio
14.
Environ Int ; 142: 105798, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32590279

RESUMEN

In this research, a novel chitosan (CS)-vanadium-titanium-magnetite (VTM) composite was designed and synthesized. The interaction between CS-VTM and Congo red (CR) dye conformed to a pseudo-second-order model to support the potent involvement of chemisorption. The effects of adsorbent dosage, reaction temperature, and initial solution pH on adsorption of CR were investigated. Approximately 99.1% of CR (100 mg/L) was adsorbed at a CS-VTM dose of 2.0 g/L or above, while such a reaction was favored at temperatures of 65 °C and pH of 6.0. Thermodynamically, the adsorption of CR proceeded spontaneously (ΔG < 0) above 35 °C. According to scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectrometer, and zeta potential analysis, its adsorption on CS-VTM can be attributed to electrostatic attraction and hydrogen bonds. The prepared CS-VTM exhibited superior adsorption performance on removal of CR as evidenced by significantly large partition coefficient of 108.3 mg g-1 µM-1 (equilibrium adsorption capacity of 62.2 mg/g at CR dose of 100 mg/L). Overall, the CS-VTM proved to be a promising and environmentally friendly adsorbent for the highly efficient and effective removal of organic dyes among the comparable sorbents studied to date.


Asunto(s)
Quitosano , Contaminantes Químicos del Agua , Adsorción , Colorantes , Óxido Ferrosoférrico , Concentración de Iones de Hidrógeno , Cinética , Titanio , Vanadio , Aguas Residuales
15.
Nanoscale ; 10(25): 11775-11781, 2018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-29714380

RESUMEN

Binary transition metal phosphides hold immense potential as innovative electrode materials for constructing high-performance energy storage devices. Herein, porous binary nickel-cobalt phosphide (NiCoP) nanosheet arrays anchored on nickel foam (NF) were rationally designed as self-supported binder-free electrodes with high supercapacitance performance. Taking the combined advantages of compositional features and array architectures, the nickel foam supported NiCoP nanosheet array (NiCoP@NF) electrode possesses superior electrochemical performance in comparison with Ni-Co LDH@NF and NiCoO2@NF electrodes. The NiCoP@NF electrode shows an ultrahigh specific capacitance of 2143 F g-1 at 1 A g-1 and retained 1615 F g-1 even at 20 A g-1, showing excellent rate performance. Furthermore, a binder-free all-solid-state asymmetric supercapacitor device is designed, which exhibits a high energy density of 27 W h kg-1 at a power density of 647 W kg-1. The hierarchical binary nickel-cobalt phosphide nanosheet arrays hold great promise as advanced electrode materials for supercapacitors with high electrochemical performance.

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