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1.
Chem Soc Rev ; 53(11): 5428-5488, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38682880

RESUMO

Elevated levels of carbon dioxide (CO2) in the atmosphere and the diminishing reserves of fossil fuels have raised profound concerns regarding the resulting consequences of global climate change and the future supply of energy. Hence, the reduction and transformation of CO2 not only mitigates environmental pollution but also generates value-added chemicals, providing a dual remedy to address both energy and environmental challenges. Despite notable advancements, the low conversion efficiency of CO2 remains a major obstacle, largely attributed to its inert chemical nature. It is imperative to engineer catalysts/materials that exhibit high conversion efficiency, selectivity, and stability for CO2 transformation. With unparalleled precision at the atomic level, atomic layer deposition (ALD) and molecular layer deposition (MLD) methods utilize various strategies, including ultrathin modification, overcoating, interlayer coating, area-selective deposition, template-assisted deposition, and sacrificial-layer-assisted deposition, to synthesize numerous novel metal-based materials with diverse structures. These materials, functioning as active materials, passive materials or modifiers, have contributed to the enhancement of catalytic activity, selectivity, and stability, effectively addressing the challenges linked to CO2 transformation. Herein, this review focuses on ALD and MLD's role in fabricating materials for electro-, photo-, photoelectro-, and thermal catalytic CO2 reduction, CO2 capture and separation, and electrochemical CO2 sensing. Significant emphasis is dedicated to the ALD and MLD designed materials, their crucial role in enhancing performance, and exploring the relationship between their structures and catalytic activities for CO2 transformation. Finally, this comprehensive review presents the summary, challenges and prospects for ALD and MLD-designed materials for CO2 transformation.

2.
Molecules ; 28(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38067499

RESUMO

The partial upgrading of "tar-like" Canadian bitumen is an essential process to reduce its viscosity to an acceptable range that meets the required pipeline specifications. An innovative and potentially greener solution has emerged in the form of microwave irradiation. This work proposes and demonstrates the use of an electrically powered commercial microwave along with carbon-based microwave susceptors (activated carbon, biochar, coke, and graphite) to promote localized thermal cracking within bitumen at a temperature as low as 150 °C, compared to the conventional method of 400 °C. The remarkable results show that just 0.1 wt% of carbon additives can reduce the viscosity of bitumen by 96% with just 10 min of microwaving at 200 °C. A Saturates, Aromatics, Resins, and Asphaltenes (SARA) analysis reveals that the mass fractions of light components (saturates) are almost doubled and that almost one-third of heavy polar hydrocarbon constituents are cracked and decomposed into much lighter molecules, resulting in higher-quality, less viscous bitumen. Furthermore, this study highlights the key role of the surface area and porosity of the carbon microwave susceptor in absorbing microwave radiation, offering exciting new avenues for optimization. Microwave-assisted partial upgrading of bitumen is a cost-effective and eco-friendly alternative to conventional upgrading, producing upgraded bitumen that requires significantly less diluent at a lower cost prior to pipeline transportation.

3.
Nano Lett ; 16(8): 5303-9, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27455174

RESUMO

One of the main challenges for advanced metallic nanoparticles (NPs) supported functional perovskite catalysts is the simultaneous achievement of a high population of NPs with uniform distribution as well as long-lasting high performance. These are also the essential requirements for optimal electrode catalysts used in solid oxide fuel cells and electrolysis cells (SOFCs and SOECs). Herein, we report a facile operando manufacture way that the crystal reconstruction of double perovskite under reducing atmosphere can spontaneously lead to the formation of ordered layered oxygen deficiency and yield segregation of massively and finely dispersed NPs. The real-time observation of this emergent process was performed via an environmental transmission electron microscope. Density functional theory calculations prove that the crystal reconstruction induces the loss of coordinated oxygen surrounding B-site cations, serving as the driving force for steering fast NP growth. The prepared material shows promising capability as an active and stable electrode for SOFCs in various fuels and SOECs for CO2 reduction. The conception exemplified here could conceivably be extended to fabricate a series of supported NPs perovskite catalysts with diverse functionalities.

4.
Inflammation ; 46(1): 359-369, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36104516

RESUMO

A cytokine storm (CS) is an out-of-control inflammatory response closely associated with the progression of diseases, such as multiple organ failure (MOF), severe sepsis, and severe or critical COVID-19. However, there is currently a lack of reliable diagnostic markers to distinguish CS from normal inflammatory responses. Tumor necrosis factor-α (TNF-α) includes transmembrane TNF-α (tmTNF-α) and secreted TNF-α (sTNF-α). The MOF mouse model in this study showed that the tmTNF-α expression changes in the neutrophils differed from the serum TNF-α and serum IL-18, INF-γ, IL-4, and IL-6. Furthermore, tmTNF-α, instead of serum TNF-α, IL-18, INF-γ, IL-4, and IL-6, reflected liver and kidney tissue damage and increased with the aggravation of these injuries. Analysis of the ROC results showed that tmTNF-α effectively distinguished between inflammatory responses and CS and efficiently differentiated between surviving and dead mice. It also significantly improved the diagnostic value of the traditional CRP marker for CS. These results indicated that the tmTNF-α expressed in the neutrophils could be used to diagnose CS in MOF mice, providing an experimental basis to further develop tmTNF-α for diagnosing CS patients.


Assuntos
COVID-19 , Fator de Necrose Tumoral alfa , Animais , Camundongos , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Interleucina-18 , Insuficiência de Múltiplos Órgãos/diagnóstico , Interleucina-4 , Síndrome da Liberação de Citocina , Biomarcadores , Teste para COVID-19
5.
ACS Omega ; 8(48): 45616-45625, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38075822

RESUMO

It is not uncommon for metals to corrode, causing the properties of the material to be affected. Superhydrophobic materials have made effective advances in metal corrosion protection because they can effectively insulate liquids from being trapped on metal surfaces. In this study, self-assembled films were formed using octadecanethiol (ODT) modification to obtain superhydrophobic as well as superoleophilic bifunctional materials. With a water contact angle (WCA) of 156°, the material surface exhibits excellent self-cleaning properties. It is also stable in highly corrosive environments. The good hydrophobicity of the material is due to the more tightly arranged conical structure and the ODT coatings of the treated copper mesh surface. The Cassie-Baxter equation calculations showed that the total exposed area of water droplets in air (91.35%) is significantly higher than the area in contact with metal surfaces. This work provides a new strategy for the design of self-assembled surface-modified superhydrophobic materials with excellent performance and stable properties by controlling the chemical composition and morphology of the material surface. The materials are prepared by avoiding cumbersome steps and the use of unusual materials and instrumentation, which allows our designs to greatly reduce the economic costs of time, labor, and raw materials, and to facilitate large-scale industrial preparation and application. The prepared superhydrophobic and superoleophilic synergistic surfaces have excellent self-cleaning properties, wetting stability, anti-corrosive properties, oil-water separation properties, coagulation properties, and durability and have a wide range of applications in the fields of anti-corrosion and seawater desalination.

6.
Chem Commun (Camb) ; 59(32): 4770-4773, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37000520

RESUMO

Prompted by the recent stepwise mechanistic proposal for the Huisgen [3+2] cycloaddition reaction between enamine and α-diazo ester, where the nucleophilic addition of the enamine carbon onto the terminal nitrogen of diazo ester is crucial, we examined the possible use of N-heterocyclic olefins (NHOs) as highly electron-rich dipolarophiles in these reactions. The mesoionic NHOs derived from 1,2,3-triazoles undergo fast [4+1] cycloaddition to give 3-(triazolium-4-yl)-(3H)-pyrazol-4-olates at room temperature. The reaction mechanism has been explored through experimental and DFT computational studies.

7.
Am J Cancer Res ; 13(5): 1923-1937, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293178

RESUMO

Exosomal proteins represent valuable research directions in the liquid biopsy of lung cancer (LC). Immunoglobulin subtypes, immunoglobulin molecules with different domains in variable regions, are products of B cell responses to different tumor antigens and are associated with tumor incidence and development. The plasma of patients with LC should theoretically contain a large number of B cell-derived exosomes that specifically recognize tumor antigens. This paper intended to assess the value of the proteomic screening of plasma exosomal immunoglobulin subtypes for diagnosing non-small cell LC (NSCLC). The plasma exosomes of NSCLC patients and healthy control participants (HCs) were isolated using ultracentrifugation. Label-free proteomics was employed to assess the differentially expressed proteins (DEPs), while the biological characteristics of the DEPs were analyzed using GO enrichment. The immunoglobulin content in the top two fold change (FC) values of the DEPs and the immunoglobulin with the lowest P-value were verified using an enzyme-linked immunosorbent assay (ELISA). The differentially expressed immunoglobulin subtypes verified via ELISA were selected to statistically analyze the receiver operating characteristic curve (ROC), after which the diagnostic values of the NSCLC immunoglobulin subtypes were determined via the ROC area under the curve (AUC). The plasma exosomes of the NSCLC patients contained 38 DEPs, of which 23 were immunoglobulin subtypes, accounting for 60.53%. The DEPs were mainly related to the binding between immune complexes and antigens. The ELISA results showed significant differences between the immunoglobulin heavy variable 4-4 (IGHV4-4) and immunoglobulin lambda variable 1-40 (IGLV1-40) in the LC patients and HCs. Compared with the HCs, the AUCs of IGHV4-4, IGLV1-40, and a combination of the two in diagnosing NSCLC were 0.83, 0.88, and 0.93, respectively, while the AUCs for non-metastatic cancer were 0.80, 0.85, and 0.89. Moreover, their diagnostic values for metastatic cancer compared to non-metastatic cancer displayed AUCs of 0.71, 0.74, and 0.83, respectively. When IGHV4-4 and IGLV1-40 were combined with serum CEA to diagnose LC, the AUC value increased, exhibiting values of 0.95, 0.89, and 0.91 for the NSCLC, non-metastatic, and metastatic groups, respectively. Plasma-derived exosomal immunoglobulins containing IGHV4-4 and IGLV 1-40 domains can provide new biomarkers for diagnosing NSCLC and metastatic patients.

8.
Front Pharmacol ; 13: 930638, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091838

RESUMO

Background: Modified Zengye Decoction (MZD), a traditional Chinese medicine, is an effective treatment for patients with primary Sjögren's syndrome (pSS). Purpose: To evaluate the efficacy of MZD and investigate its effect on plasma exosomal proteins. Methods: Eighteen pSS patients were treated with MZD for 2 weeks. The therapeutic effect was evaluated by observing the changes in clinical symptoms, laboratory parameters, and plasma cytokines before and after treatment. Then, the differentially expressed proteins (DEPs) in the plasma exosomes before and after treatment were identified via label-free proteomics, while Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were used to analyze the possible biological functions and signaling pathways involved in the exosomal DEPs. Results: MZD can effectively relieve the clinical symptoms of pSS patients, downregulate the plasma IgG and IgM levels, and inhibit plasma cytokine production. Thirteen DEPs were identified via label-free proteomics in the plasma exosomes before and after MZD treatment, of which 12 were downregulated proteins. GO analysis showed that these downregulated proteins were mainly related to the insulin response involved in dryness symptoms and the Gram-negative bacterial defense response and proteoglycan binding involved in infection. KEGG enrichment analysis showed that these downregulated proteins were primarily associated with the porphyrin metabolism involved in oteoarthrosis and the NF-κB and TLR4 pathways involved in infection. Conclusion: MZD can effectively alleviate SS symptoms, while its mechanism may be associated with the reduced protein expression in insulin response, porphyrin metabolism, and the TLR4/NF-κB pathway.

9.
Chem Commun (Camb) ; 57(50): 6137-6140, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34042131

RESUMO

Mesoionic N-heterocyclic olefins (mNHOs) were first reported last year and their reactivity remains largely unexplored. Herein we report the reaction of unprotected mNHOs and organic azides as a novel synthetic route to a variety of pyrazolo[3,4-d][1,2,3]triazoles, an important structural motif in drug candidates and energetic materials. The only byproduct aniline can be easily recycled and converted back to the starting organic azide, in compliance with the green chemistry principle. The reaction mechanism has been explored through experimental and computational studies.

10.
ACS Appl Mater Interfaces ; 12(14): 16209-16215, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32180390

RESUMO

Solid oxide fuel cells (SOFCs) offer opportunities for the application as both power sources and chemical reactors. Yet, it remains a grand challenge to simultaneously achieve high efficiency of transforming higher hydrocarbons to value-added products and of generating electricity. To address it, we here present an ingenious approach of nanoengineering the triple-phase boundary of an SOFC anode, featuring abundant Co7W6@WOx core-shell nanoparticles dispersed on the surface of black La0.4Sr0.6TiO3. We also developed a cofeeding strategy, which is centered on concurrently feeding the SOFC anode with H2 and chemical feedstock. Such combined optimizations enable effective (electro)catalytic dehydrogenation of n-butane to butenes and 1,3-butadiene. The C4 alkene yield is higher than 50% while the peak power density of the SOFC reached 212 mW/cm2 at 650 °C. In addition, coke formation is largely suppressed and little CO/CO2 is produced in this process. While this work shows new possibility of chemical-electricity coupling in SOFCs, it might also open bona fide avenues toward the electrocatalytic synthesis of chemicals at higher temperatures.

11.
Artigo em Zh | MEDLINE | ID: mdl-26930904

RESUMO

OBJECTIVE: To investigate the correlation between tongue body MRI measurements and the lingual region obstruction in patients with obstructive sleep apnea hypopnea syndrome (obstructive sleep apnea hypopnea syndrome, OSAHS), and the relationship of two diagnosis methods in positioning obstructive level, in order to improve the preoperative diagnostic accuracy of obstructive level in OSAHS patients . METHOD: Fifty-nine patients with OSAHS definited by the AG200 sleep apnea monitoring and obstruction plane positioning system was included. They all underwent tongue MRI scan, after three-dimensional reconstruction, the tongue body length to diameter, relative thickness, basal diameter, wide around central about wide diameter and tongue body volume were measured. The lower blocking (mainly composed of lingual region) constituent ratio P established by AG200 was correlated with tongue parameters measured by MRI. At the same time, To analysis of differences of P in patients with different degree of OSAHS. RESULT: Among these patients with OSAHS in different degree, the coefficient correlation between tongue parameters(tongue length, relative thickness, basal diameter, wide middle diameter, tongue body volume) and lower blocking constitute ratio P werer LP = 0.051,rHP = 0.069, r1 = 0.215, r2 = 0.147, rVP = 0.259, respectively. lower obstruction of form than the differences had statistical significance. The measured tongue parameters and value P(the lower blocking constituent ratio) were negatively correlated, which demonstrated that exclusing of the larynx and hypopharynx airway obstruction, the lower airway obstruction detected by AG200 was related with tongue parameters measured by MRI, and was strongestly related with the tongue body volume. CONCLUSION: The volume of tongue and AG had correlation in judgement of lower blocking. In OSAHS patients the lower blocking constituent ratio varies between the defferent severity groups of the disease, the combina tion of the two method can be used to predict the obstructive plane in OSAHS patients with upper airway obstruction, and provide the basis for the individual treatment of patients with OSAHS.


Assuntos
Obstrução das Vias Respiratórias/complicações , Imageamento por Ressonância Magnética , Apneia Obstrutiva do Sono/diagnóstico , Língua/patologia , Humanos , Imageamento Tridimensional , Sono
12.
Environ Health Perspect ; 117(10): 1612-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20019914

RESUMO

BACKGROUND: With the increase of motor vehicles, ambient air pollution related to traffic exhaust has become an important environmental issue in China. Because of their fast growth and development, children are more susceptible to ambient air pollution exposure. Many chemicals from traffic exhaust, such as carbon monoxide, nitrogen dioxide, and lead, have been reported to show adverse effects on neurobehavioral functions. Several studies in China have suggested that traffic exhaust might affect neurobehavioral functions of adults who have occupational traffic exhaust exposure. However, few data have been reported on the effects on neurobehavioral function in children. OBJECTIVES: The objective of this study was to explore the association between traffic-related air pollution exposure and its effects on neurobehavioral function in children. METHODS: This field study was conducted in Quanzhou, China, where two primary schools were chosen based on traffic density and monitoring data of ambient air pollutants. School A was located in a clear area and school B in a polluted area. We monitored NO(2) and particulate matter with aerodynamic diameter < or = 10 mum as indicators for traffic-related air pollution on the campuses and in classrooms for 2 consecutive days in May 2005. The children from second grade (8-9 years of age) and third grade (9-10 years of age) of the two schools (n = 928) participated in a questionnaire survey and manual-assisted neurobehavioral testing. We selected 282 third-grade children (school A, 136; school B, 146) to participate in computer-assisted neurobehavioral testing. We conducted the fieldwork between May and June 2005. We used data from 861 participants (school A, 431; school B, 430) with manual neurobehavioral testing and from all participants with computerized testing for data analyses. RESULTS: Media concentrations of NO(2) in school A and school B campus were 7 microg/m(3) and 36 microg/m(3), respectively (p < 0.05). The ordinal logistic regression analyses showed that, after controlling the potential confounding factors, participants living in the polluted area showed poor performance on all testing; differences in results for six of nine tests (66.7%) achieved statistical significance: Visual Simple Reaction Time with preferred hand and with nonpreferred hand, Continuous Performance, Digit Symbol, Pursuit Aiming, and Sign Register. CONCLUSION: We found a significant relationship between chronic low-level traffic-related air pollution exposure and neurobehavioral function in exposed children. More studies are needed to explore the effects of traffic exhaust on neurobehavioral function and development.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar , Exposição Ambiental , Desempenho Psicomotor/efeitos dos fármacos , Emissões de Veículos/análise , Poluição do Ar/análise , Criança , China , Cognição/efeitos dos fármacos , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/toxicidade , Material Particulado/análise , Material Particulado/toxicidade , Inquéritos e Questionários
13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(11): 1073-6, 2007 Nov.
Artigo em Zh | MEDLINE | ID: mdl-18396658

RESUMO

OBJECTIVE: To explore the effects of traffic exhausts on children's neurobehavioral functions. METHODS: A field study was conducted in Quanzhou, Fujian province where two primary schools were chosen based on the numbers of automobiles passing by,and the data of ambient air pollutants from the monitoring system. School B and School A located at the high traffic exhausts pollution area and the clear area, respectively. Neurobehavioral functions of pupils in grade 2 and 3 were scored. RESULTS: School B had very similar score of Ruiwen Test with School A, while the score of Digit Eras Test was lower than that in School A with marginal significance. The scores of Digit Symbol,Aim Tracing, Sign Register and Cormect Number test were 38.5 +/- 9.96, 84.3 +/- 27.83, 37.4 +/- 11.62 and 17.1 +/- 5.88 in School B,respectively, which were significantly lower than those in School A (41.6 +/- 12.97, 95.5 +/- 35.80, 42.3 +/- 15.58 and 18.7 +/- 5.78) respectively. Scores in Digit Symbol,Aim Tracing,Sign Register and Cormect Number of pupils in School B were 2.9, 11.5, 5.6 and 1.6 lower than those in School A after adjusting on other confounding factors. CONCLUSION: It was suggested that traffic exhausts might cause damage to children's neurobehavioral functions.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Exposição Ambiental/efeitos adversos , Desempenho Psicomotor , Emissões de Veículos/análise , Poluição do Ar/análise , Criança , China , Feminino , Humanos , Masculino
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