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1.
Inorg Chem ; 63(5): 2756-2765, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38252459

RESUMO

Electrocatalytic nitrate reduction reaction (EC-NITRR) shows a significant advantage for green reuse of the nitrate (NO3-) pollutant. However, the slow diffusion reaction limits the reaction rate in practical EC-NITRR, causing an unsatisfactory ammonia (NH3) yield. In this work, a multifunctional NiFe-LDH/CeO2 with the dual adsorption effect (physisorption and chemisorption) and dual-metal sites (Ce3+ and Fe2+) was fabricated by the electrodeposition method. NiFe-LDH/CeO2 performed an expected ability of enrichment for NO3- through the pseudo-first-order and pseudo-second-order kinetic models, and the polymetallic structure provided abundant sites for effective reaction of NO3-. At-0.6 V vs RHE, the ammonia (NH3) yield of NiFe-LDH/CeO2 reached 335.3 µg h-1 cm-2 and the selectivity of NH3 was 24.2 times that of NO2-. The nitrogen source of NH3 was confirmed by 15NO3- isotopic labeling. Therefore, this work achieved the recycling of the NO3- pollutant by synergy of enrichment and catalysis, providing an alternative approach for the recovery of NO3- from wastewater.

2.
Phys Chem Chem Phys ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101517

RESUMO

SO3 is an important reactive species in sulfur cycle and sulfuric acid formation processes and its reactions with some functional group substances, such as H2O, NH3, CH3OH, and organic and inorganic acids, have been extensively studied. However, its loss mechanism with multifunctional species is still lacking in detail. Herein, the reaction mechanism between SO3 and monoethanolamide (MEA) was investigated in the gas phase and on water droplets. The quantum chemical calculations indicate that the gas-phase reactions of SO3 with the OH and NH2 moieties of MEA hardly occur as their reaction energy barriers are up to 21.9-29.4 kcal mol-1. When a single water molecule is added into the SO3 + MEA reaction, it not only decreases the reaction barrier by at least 15.0 kcal mol-1 and thus enhances the rate obviously, but can also lead to the main product changing from HOCH2CH2NHSO3H to NH2CH2CH2OSO3H. The Born Oppenheimer molecular dynamics simulations on a water droplet show that the routes of the NH2CH2CH2OSO3-⋯H3O+ ion pair, HSO4- and HOCH2CH2NH3+ ions and zwitterionic formations of HOCH2CH2NH2+-SO3- and SO3--OCH2CH2NH3+ occur through a loop-structure route or chain reaction process, and can be finished within several picoseconds. Interestingly, the nucleation simulations show that the products of HOCH2CH2NHSO3H and NH2CH2CH2OSO3H have a potential ability to participate in the formation of new particles as they can form larger clusters with H2SO4, NH3 and H2O molecules within 20 ns. Thus, the present study will not only give new insight into the reaction between SO3 and multifunctional compounds, but also provide a new potential formation mechanism for particles resulting from the loss of SO3.

3.
J Sep Sci ; 47(1): e2300535, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37933692

RESUMO

In this article, a highly crystalline porous imine-based covalent organic framework was synthesized at room temperature and used as solid-phase extraction (SPE) adsorbent for the purification and enrichment of trace sulfonamides (SAs) from food samples. The structure of the obtained material was characterized and studied in detail. The extraction process was optimized and the final elution was determined by the ultra-high-performance liquid chromatography-quadrupole time of flight mass spectrometry method. Low limits of detection (0.02-0.19 µg/kg) were obtained under optimal conditions, with the recoveries ranging from 70.5% to 105.3% when spiked at different levels. The adsorption process of the material for SAs was fitted by the Langmuir and Freundlich adsorption isotherm model, and the extraction capacity for Nitrofuran metabolites from food samples was also investigated for comparison. The results demonstrated that the framework was a good candidate SPE adsorbent that can be used for the enrichment of drug residues in complex matrix, and the work may provide a systematic study method for the development of porous adsorbents.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Cromatografia Líquida de Alta Pressão/métodos , Iminas , Sulfonamidas/análise , Porosidade , Extração em Fase Sólida/métodos
4.
MAGMA ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922525

RESUMO

OBJECT: To review recent advances of artificial intelligence (AI) in enhancing the efficiency and throughput of the MRI acquisition workflow in neuroimaging, including planning, sequence design, and correction of acquisition artifacts. MATERIALS AND METHODS: A comprehensive analysis was conducted on recent AI-based methods in neuro MRI acquisition. The study focused on key technological advances, their impact on clinical practice, and potential risks associated with these methods. RESULTS: The findings indicate that AI-based algorithms have a substantial positive impact on the MRI acquisition process, improving both efficiency and throughput. Specific algorithms were identified as particularly effective in optimizing acquisition steps, with reported improvements in workflow efficiency. DISCUSSION: The review highlights the transformative potential of AI in neuro MRI acquisition, emphasizing the technological advances and clinical benefits. However, it also discusses potential risks and challenges, suggesting areas for future research to mitigate these concerns and further enhance AI integration in MRI acquisition.

5.
Magn Reson Med ; 90(2): 417-431, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37066854

RESUMO

PURPOSE: Optimizing three-dimensional (3D) k-space sampling trajectories is important for efficient MRI yet presents a challenging computational problem. This work proposes a generalized framework for optimizing 3D non-Cartesian sampling patterns via data-driven optimization. METHODS: We built a differentiable simulation model to enable gradient-based methods for sampling trajectory optimization. The algorithm can simultaneously optimize multiple properties of sampling patterns, including image quality, hardware constraints (maximum slew rate and gradient strength), reduced peripheral nerve stimulation (PNS), and parameter-weighted contrast. The proposed method can either optimize the gradient waveform (spline-based freeform optimization) or optimize properties of given sampling trajectories (such as the rotation angle of radial trajectories). Notably, the method can optimize sampling trajectories synergistically with either model-based or learning-based reconstruction methods. We proposed several strategies to alleviate the severe nonconvexity and huge computation demand posed by the large scale. The corresponding code is available as an open-source toolbox. RESULTS: We applied the optimized trajectory to multiple applications including structural and functional imaging. In the simulation studies, the image quality of a 3D kooshball trajectory was improved from 0.29 to 0.22 (NRMSE) with Stochastic optimization framework for 3D NOn-Cartesian samPling trajectorY (SNOPY) optimization. In the prospective studies, by optimizing the rotation angles of a stack-of-stars (SOS) trajectory, SNOPY reduced the NRMSE of reconstructed images from 1.19 to 0.97 compared to the best empirical method (RSOS-GR). Optimizing the gradient waveform of a rotational EPI trajectory improved participants' rating of the PNS from "strong" to "mild." CONCLUSION: SNOPY provides an efficient data-driven and optimization-based method to tailor non-Cartesian sampling trajectories.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética , Humanos , Imageamento Tridimensional/métodos , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Rotação
6.
Opt Lett ; 48(9): 2261-2264, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37126249

RESUMO

We demonstrate fabrication of a 30-cm-long thin-film lithium niobate (TFLN) optical delay line (ODL) incorporated with segmented microelectrodes of 24-cm total length using the femtosecond laser lithography technique. The transmission spectra of the unbalanced Mach-Zehnder interferometers (MZIs) reveal an ultra-low propagation loss of 0.025 dB/cm. The device exhibits a low half-wave voltage of 0.45 V, corresponding to a voltage-length product of 10.8 V·cm, which is equivalent to 5.4 V·cm in the push-pull configuration. We also demonstrate a high electro-optic (EO) tuning efficiency of 3.146 fs/V and a continuous tuning range of 220 fs in the fabricated ODL.

7.
Inorg Chem ; 62(16): 6499-6509, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37036090

RESUMO

Electrochemical oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) is a promising approach to produce high-value chemicals such as 2,5-furandicarboxylic acid (FDCA). However, the undesirable stability of catalysts commonly limits its potential application value. In this work, NiOOH derived from Ni(OH)2 was determined as the main catalytic site for HMF oxidation, but the collapse of Ni(OH)2 caused severe instability during the electrocatalytic process because of the crystal structure mismatch between NiOOH and Ni(OH)2. The implantation of Ce in Ni(OH)2 (Ce-Ni(OH)2) was successfully realized to address the stability issue of bare Ni(OH)2, since the larger ion radius of Ce could increase the Ni-O bond length and d-spacing. As a result, the activity of 14%Ce-Ni(OH)2 has not obviously decayed after the 50 cyclic voltammetry (CV)-cycle test. HMF conversion is close to 100%, and the Faraday efficiency (FE) reaches 86.6% at the potential of 0.45 V vs Ag/AgCl. This study provides a new strategy to design stable catalysts for the conversion of biomass derivatives.

8.
J Environ Manage ; 340: 117973, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37119626

RESUMO

This paper is to discuss the impact of green mergers and acquisitions (GMA) on illegal pollution discharge (ILP). The diurnal difference pollution data of the nearest monitoring station around heavy polluting enterprises are used to measure ILP. Results show that: (1) Compared with polluting firms that have not conducted GMA, GMA can reduce ILP by 2.9%. (2) Large scale, strong industrial correlation and cash payment of GMA is more conducive to controlling ILP. GMA in the same city is easier to inhibit ILP. (3) Impact paths of GMA on ILP mainly include cost effect, technology effect and responsibility effect. GMA aggravates ILP by increasing management costs and risk control risks. GMA inhibits ILP by increasing green innovation, environmental protection investment, social responsibility performance and environmental information disclosure. (4) GMA has a greater inhibition effect on ILP in state-owned firms, technology-intensive firms and eastern firms. (5) The industrial spillover effect of GMA is more obvious than that of the same city. This paper provides implications for curbing ILP from the perspective of GMA.


Assuntos
Revelação , Poluição Ambiental , Indústrias , Investimentos em Saúde , Tecnologia , China , Conservação dos Recursos Naturais
9.
Biochem Biophys Res Commun ; 559: 183-190, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-33945996

RESUMO

Oral squamous cell carcinoma (OSCC) is one of the causes of cancer-related death worldwide. The abnormal proliferation ability of OSCC has become one of the major reasons for its poor prognosis. FK-506 binding protein 11 (FKBP11) is abnormally expressed in malignant tumors and affects many biological processes. The purpose of this study is to investigate the effect of FKBP11 on cell proliferation in OSCC and explore the possible regulatory mechanism. The expression of FKBP11 was detected by western blotting (WB) and/or real-time PCR in OSCC and paracancerous normal tissues in tongue squamous cell carcinoma (TSCC) cell lines, revealing high expression in OSCC and CAL-27 cells. Furthermore, FKBP11 knockdown inhibited the proliferation of CAL-27 cells by CCK-8 and colony formation assays. G2/M arrest and induction of apoptosis were observed using flow cytometry, Hoechst 33258 and Calcein-AM/PI staining, accompanied by changes in some cell cycle- and apoptosis-related proteins, including CDK1, Cyclin B1, p21, p27, p53, Bax, Bcl-2 and Caspase-3. Additionally, the expression of these proteins can be reversed by the use of pifithrin-α (PFT-α), a p53 inhibitor. An in vivo xenograft model further confirmed that FKBP11 enhanced OSCC progression. In conclusion, FKBP11 could promote cell proliferation by regulating G2/M phase and apoptosis via the p53/p21/p27 and p53/Bcl-2/Bax pathways, respectively, which suggests that it may be a new candidate target for the treatment of OSCC.


Assuntos
Carcinogênese/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia , Transdução de Sinais , Proteínas de Ligação a Tacrolimo/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Apoptose/genética , Carcinogênese/genética , Carcinoma de Células Escamosas/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Bucais/genética , Proteínas de Ligação a Tacrolimo/genética
10.
Molecules ; 26(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202485

RESUMO

In this work, steam explosion (SE) was exploited as a potential hydrothermal-humification process of vegetable wastes to deconstruct their structure and accelerate their decomposition to prepare humified substances. Results indicated that the SE process led to the removal of hemicellulose, re-condensation of lignin, degradation of the cellulosic amorphous region, and the enhancement of thermal stability of broccoli wastes, which provided transformable substrates and a thermal-acidic reaction environment for humification. After SE treatment, total humic substances (HS), humic acids (HAs), and fulvic acids (FAs) contents of broccoli samples accounted for up to 198.3 g/kg, 42.3 g/kg, and 166.6 g/kg, and their purification were also facilitated. With the increment of SE severity, structural characteristics of HAs presented the loss of aliphatic compounds, carbohydrates, and carboxylic acids and the enrichment of aromatic structures and N-containing groups. Lignin substructures were proved to be the predominant aromatic structures and gluconoxylans were the main carbohydrates associated with lignin in HAs, both of their signals were enhanced by SE. Above results suggested that SE could promote the decomposition of easily biodegradable matters and further polycondensation, aromatization, and nitrogen-fixation reactions during humification, which were conducive to the formation of HAs.


Assuntos
Benzopiranos/química , Substâncias Húmicas , Eliminação de Resíduos , Vapor , Verduras/química
11.
Molecules ; 25(11)2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32503303

RESUMO

In this work, lignin fractionation is proposed as an effective approach to reduce the heterogeneity of lignin and improve the adsorption and recycle performances of lignin as a cationic dye adsorbent. By stepwise dissolution of enzymatic hydrolysis lignin in 95% and 80% ethanol solutions, three lignin subdivisions (95% ethanol-soluble subdivision, 80% ethanol-soluble subdivision, and 80% ethanol-insoluble subdivision) were obtained. The three lignin subdivisions were characterized by gel permeation chromatography (GPC), FTIR, 2D-NMR and scanning electron microscopy (SEM), and their adsorption capacities for methylene blue were compared. The results showed that the 80% ethanol-insoluble subdivision exhibited the highest adsorption capacity and its value (396.85 mg/g) was over 0.4 times higher than that of the unfractionated lignin (281.54 mg/g). The increased adsorption capacity was caused by the enhancement of both specific surface area and negative Zeta potential. The maximum monolayer adsorption capacity of 80% ethanol-insoluble subdivision by adsorption kinetics and isotherm studies was found to be 431.1 mg/g, which was much higher than most of reported lignin-based adsorbents. Moreover, the 80% ethanol-insoluble subdivision had much higher regeneration yield (over 90% after 5 recycles) compared with the other two subdivisions. Consequently, the proposed fractionation method is proved to be a novel and efficient non-chemical modification approach that significantly improves adsorption capacity and recyclability of lignin.


Assuntos
Cátions/isolamento & purificação , Celulase/metabolismo , Fracionamento Químico/métodos , Etanol/química , Lignina/metabolismo , Azul de Metileno/isolamento & purificação , Água/química , Adsorção , Cátions/análise , Lignina/química , Lignina/isolamento & purificação , Azul de Metileno/análise
12.
Biologicals ; 55: 1-16, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30093175

RESUMO

A fundamental aspect of biological product safety is to assure absence of adventitious agents in the final product. Next-generation or high-throughput sequencing (NGS/HTS) has recently demonstrated detection of viruses that were previously missed using the recommended routine assays for adventitious agent testing of biological products. This meeting was co-organized by the International Alliance for Biological Standardization (IABS) and the U.S. Food and Drug Administration (FDA) to assess the current status and discuss the readiness of NGS for adventitious virus detection in biologics. The presentations included efforts for standardization, case studies on applications in biologics, comparison with routine virus detection assays, and current regulatory thinking. Participants identified the need for standard reference reagents, well-annotated databases, large data storage and transfer capacity, personnel with relevant expertise, particularly in bioinformatics; and harmonization of international regulations for testing biologic products and reagents used for their manufacturing. We hope this meeting summary will be of value to regulators and industry for considerations of NGS applications for adventitious virus detection in biologics.


Assuntos
Adenoviridae/genética , Sequenciamento de Nucleotídeos em Larga Escala , Animais , Congressos como Assunto , Humanos , Estados Unidos , United States Food and Drug Administration
13.
Luminescence ; 32(6): 999-1008, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28181726

RESUMO

The red-emitting phosphor Ca0.8 Zn0.2 TiO3 :Pr3+ was synthesized using an ethylene glycol (EG)-assisted hydrothermal method. The effects of additional amounts of and order of adding EG, plus hydrothermal temperature, time, and pH on the composition, morphology and optical properties of the titanate phosphors were studied. The crystalline phases of the titanate phosphors were confirmed to be constituted of a series of co-existing CaTiO3 , Zn2 TiO4 and Ca2 Zn4 Ti16 O38 compounds in various proportions that were visualized using an X-ray diffractometer (XRD). The optical properties of the phosphors were studied using photoluminescence spectra and UV-visible spectroscopy. The results show that the impurities Zn2 TiO4 :Pr3+ and Ca2 Zn4 Ti16 O38 :Pr3+ significantly contributed to the enhancement of an absorption band around 380 nm. The optimum Ca0.8 Zn0.2 TiO3 :Pr3+ phosphor consisting of appropriate amounts of CaTiO3 , Ca2 Zn4 Ti16 O38 and Zn2 TiO4 in three phases was achieved by controlling the hydrothermal conditions, and the obtained red phosphor exhibited the highest red emission (1 D2  â†’ 3 H4 transition of Pr3+ ) with an ideal chromaticity coordinate located at (x = 0.667, y = 0.332) under 380 nm excitation.


Assuntos
Európio/química , Substâncias Luminescentes/química , Praseodímio/química , Titânio/química , Zinco/química , Luminescência , Substâncias Luminescentes/síntese química , Medições Luminescentes , Temperatura
14.
Bull Environ Contam Toxicol ; 99(2): 270-275, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28500355

RESUMO

Direct head-space solid-phase microextraction (HS-SPME) of phenols in water is usually difficult due to its polarity and solubility in aqueous matrix. Herein we report the fabrication of metal-organic framework MOF-177 coated stainless steel fiber for the HS-SPME of phenols (2-methylolphenol, 4-methylolphenol, 2,4-dimethylolphenol, 2,4-dichlorphenol, and 3-methyl-4-chlorophenol) in environmental water samples prior to the gas chromatography-mass spectrometry detection. Several parameters affecting the extraction efficiency were optimized in the experiment, including extraction temperature and time, the pH value and salt addition. The results indicated that the coated fiber gave low detection limits (0.015-0.043 µg L-1) and good repeatability with the RSD ranging from 2.8% to 5.5% for phenols. The recoveries are between 84.5%-98.6% with the spiked level of 10 µg L-1 for the real water samples. The established method may afford a kind of potential enrichment material and a reference method for the analysis of methylphenols in water samples.


Assuntos
Fenóis/análise , Microextração em Fase Sólida/instrumentação , Poluentes Químicos da Água/análise , Clorofenóis/análise , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Microextração em Fase Sólida/métodos , Aço Inoxidável/química , Temperatura
15.
Molecules ; 19(11): 19050-65, 2014 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-25415471

RESUMO

Several pleuromutilin derivatives possessing thiadiazole moieties were synthesized via acylation reactions under mild conditions. The in vitro antibacterial activities of the derivatives against methicillin-resistant S. aureus, methicillin-resistant S. epidermidis, S. aureus, S. epidermidis, E. coli, and B. cereus were tested by the agar dilution method and Oxford cup assay. All the screened compounds displayed potent activity. Compound 6d was the most active antibacterial agent because of its lowest MIC value and largest inhibition zone. Docking experiments were performed to understand the possible mode of the interactions between the derivatives and 50S ribosomal subunit. Moreover, the absorption, distribution, metabolism, excretion and toxicity properties of the synthesized compounds were analyzed after prediction using the Advanced Chemistry Development/Percepta Platform available online.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Diterpenos/síntese química , Diterpenos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Simulação de Acoplamento Molecular , Compostos Policíclicos , Pleuromutilinas
16.
Int J Biol Macromol ; 258(Pt 2): 128963, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154721

RESUMO

Nano-lignin presents great potential in advanced carbon materials preparation since it integrates the advantages of nanomaterials as well the preferable properties of lignin (e.g. high carbon content and highly aromatic structure). Herein, lignin-derived carbon nanosphere supported Pd catalysts (Pd@LCNS) were prepared via a two-step carbonization of Pd2+ adsorbed lignin nanospheres (LNS) and applied in vanillin hydrodeoxygenation. The effect lignin heterogeneity on the synthesis of Pd@LCNS as well as its catalytic performance was further investigated through the synthesis of Pd@LCNS using three lignin fractions with different molecular weight. The results showed that the three Pd@LCNSs exhibited significant differences in the morphology of both carbon support and Pd nanoparticles. Pd@LCNS-3 prepared from high molecular weight lignin fraction (L-3) presented stable carbon nanosphere support with the smallest particle size (∼150 nm) and the highest Pd loading amount (3.78 %) with the smallest Pd NPs size (∼1.6 nm). Therefore, Pd@LCNS-3 displayed superior catalytic activity for vanillin hydrodeoxygenation (99.34 % of vanillin conversion and 99.47 % of 2-methoxy-4-methylphenol selectivity) at 90 °C without H2. Consequently, this work provides a sustainable strategy to prepare uniformly dispersed lignin-based carbon-supported Pd catalyst using high molecular weight lignin as the feedstock and further demonstrate its superior applicability in the selective transfer hydrogenation of vanillin.


Assuntos
Benzaldeídos , Carbono , Nanosferas , Carbono/química , Lignina/química , Hidrogenação
17.
Adv Colloid Interface Sci ; 329: 103176, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38761603

RESUMO

Single-atom catalysts (SACs) with active metals dispersed atomically have shown great potential in heterogeneous catalysis due to the high atomic utilization and superior selectivity/stability. Synthesis of SACs using carbon-neutral biomass and its components as the feedstocks provides a promising strategy to realize the sustainable and cost-effective SACs preparation as well as the valorization of underused biomass resources. Herein, we begin by describing the general background and status quo of carbon-based SACs derived from biomass. A detailed enumeration of the common biomass feedstocks (e.g., lignin, cellulose, chitosan, etc.) for the SACs preparation is then offered. The interactions between metal atoms and biomass-derived carbon carriers are summarized to give general rules on how to stabilize the atomic metal centers and rationalize porous carbon structures. Furthermore, the widespread adoption of catalysts in diverse domains (e.g., chemocatalysis, electrocatalysis and photocatalysis, etc.) is comprehensively introduced. The structure-property relationships and the underlying catalytic mechanisms are also addressed, including the influences of metal sites on the activity and stability, and the impact of the unique structure of single-atom centers modulated by metal/biomass feedstocks interactions on catalytic activity and selectivity. Finally, we end this review with a look into the remaining challenges and future perspectives of biomass-based SACs. We expect to shed some light on the forthcoming research of carbon-based SACs derived from biomass, manifestly stimulating the development in this emerging research area.


Assuntos
Biomassa , Carbono , Catálise , Carbono/química , Metais/química
18.
Int J Biol Macromol ; 268(Pt 2): 131937, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685539

RESUMO

As a cellulose-derived material, nanocellulose possesses unique properties that make it an ideal substrate for various functional composite materials. In this study, we developed a novel composite membrane material capable of adsorbing and photo-catalyzing formaldehyde by immobilizing HKUST-1 (copper open framework composed of 1,3,5-benzenetricarboxylic acid) onto NFC (Nano-fibrillated cellulose) membranes and subsequently loading modified carbon nitride. The synthesized CNx@HN composite membrane (consisting of NFC membrane with anchored HKUST-1 and modified g-C3Nx nanosheets) was thoroughly characterized, and its photocatalytic degradation performance towards low concentrations of formaldehyde (3.0 mg/m3) was investigated. The results demonstrated that HKUST-1's porous nature exhibited a concentrated adsorption capacity for formaldehyde, while the modified CNx (Modified g-C3Nx nanosheets) displayed robust photocatalytic degradation of formaldehyde. The synergistic effect of HKUST-1 and modified CNx on the NFC membrane significantly enhanced the efficiency of formaldehyde degradation. Under xenon lamp irradiation, CNx@HN-5 achieved a total removal efficiency of 86.9 % for formaldehyde, with a photocatalytic degradation efficiency of 48.45 %, showcasing its exceptional ability in both adsorption and photocatalytic degradation of formaldehyde. Furthermore, after 10 cycles of recycling, the composite membrane exhibited excellent stability for the photocatalytic degradation process. Therefore, this study presents a green and facile strategy to fabricate nanocellulose-supported composite membranes with great potential for practical applications in formaldehyde degradation.


Assuntos
Celulose , Formaldeído , Nitrilas , Formaldeído/química , Celulose/química , Nitrilas/química , Catálise , Adsorção , Membranas Artificiais , Fotólise , Estruturas Metalorgânicas
19.
Int J Pharm ; 657: 124189, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38701906

RESUMO

Amorphous solid dispersions (ASDs) represent an important approach for enhancing oral bioavailability for poorly water soluble compounds; however, assuring that these ASDs do not recrystallize to a significant extent during storage can be time-consuming. Therefore, various efforts have been undertaken to predict ASD crystallization levels with kinetic models. However, only limited success has been achieved due to limits on crystal content quantification methods and the complexity of crystallization kinetics. To increase the prediction accuracy, the accelerated stability assessment program (ASAP), employing isoconversion (time to hit a specification limit) and a modified Arrhenius approach, are employed here for predictive shelf-life modeling. In the current study, a model ASD was prepared by spray drying griseofulvin and HPMC-AS-LF. This ASD was stressed under a designed combinations of temperature, relative humidity and time with the conditions set to ensure stressing was carried out below the glass transition temperature (Tg) of the ASD. Crystal content quantification method by X-ray powder diffraction (XRPD) with sufficient sensitivity was developed and employed for stressed ASD. Crystallization modeling of the griseofulvin ASD using ASAPprime® demonstrated good agreement with long-term (40 °C/75 %RH) crystallinity levels and support the use of this type of accelerated stability studies for further improving ASD shelf-life prediction accuracy.


Assuntos
Cristalização , Estabilidade de Medicamentos , Griseofulvina , Griseofulvina/química , Derivados da Hipromelose/química , Difração de Raios X/métodos , Solubilidade , Composição de Medicamentos/métodos , Química Farmacêutica/métodos , Temperatura , Umidade
20.
Exp Neurol ; 377: 114804, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38704083

RESUMO

BACKGROUND: Sevoflurane (SEV) has been found to induce neurotoxicity and cognitive impairment, leading to the development of degenerative diseases. Protein kinase C delta (PRKCD) is upregulated in the hippocampus of SEV-treated mice and may be related to SEV-related neurotoxicity. However, the underlying molecular mechanisms by which SEV mediates neurotoxicity via PRKCD remain unclear. METHODS: Normal mice and PRKCD knockout (KO) mice were exposed to SEV. Hippocampal neurons were isolated from mice hippocampal tissues. H&E staining was used for pathological morphology of hippocampal tissues, and NISSL staining was used to analyze the number of hippocampal neurons. The mRNA and protein levels were determined using quantitative real-time PCR, western blot, immunofluorescence staining and immunohistochemical staining. The mitochondrial microstructure was observed by transmission electron microscopy. Cell viability was detected by cell counting kit 8 assay, and ferroptosis was assessed by detecting related marker levels. The cognitive ability of mice was assessed by morris water maze test. And the protein levels of PRKCD, ferroptosis-related markers and Hippo pathway-related markers were examined by western bolt. RESULTS: SEV increased PRKCD expression and ferroptosis in hippocampal tissues of mice. Also, SEV promoted mouse hippocampal neuron injury by inducing ferroptosis via upregulating PRKCD expression. Knockout of PRKCD alleviated SEV-induced neurotoxicity and cognitive impairment in mice, and relieved SEV-induced ferroptosis in hippocampal neurons. PRKCD could inhibit the activity of Hippo pathway, and its knockdown also overturned SEV-mediated ferroptosis by activating Hippo pathway. CONCLUSION: SEV could induce neurotoxicity and cognitive impairment by promoting ferroptosis via inactivating Hippo pathway through increasing PRKCD expression.


Assuntos
Disfunção Cognitiva , Ferroptose , Via de Sinalização Hippo , Hipocampo , Camundongos Knockout , Proteína Quinase C-delta , Proteínas Serina-Treonina Quinases , Sevoflurano , Transdução de Sinais , Regulação para Cima , Animais , Sevoflurano/toxicidade , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Disfunção Cognitiva/genética , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Regulação para Cima/efeitos dos fármacos , Proteína Quinase C-delta/metabolismo , Proteína Quinase C-delta/genética , Ferroptose/efeitos dos fármacos , Ferroptose/fisiologia , Camundongos Endogâmicos C57BL , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Anestésicos Inalatórios/toxicidade , Síndromes Neurotóxicas/patologia , Síndromes Neurotóxicas/metabolismo
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