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1.
Bioresour Technol ; 388: 129746, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37689119

RESUMO

In this study, impregnation combined with KOH activation with different mixing methods was used to prepare magnetic biochar. The effects of synthetic method on biochar physicochemical properties and adsorption performance were explored. The results showed that treatment of a Fe-Zn oxide with KOH activation provided excellent adsorption properties with adsorption capacity of 458.90 mg/g due to well-developed microporous structure and rich-in O-containing functional groups as well as exposed oxidizing functional groups (Fe2O3 and FeOOH). Langmuir-Freundlich and pseudo-second-order models accurately fit phenol adsorption. Neutral conditions (pH = 6) and lower ionic strengths were beneficial to phenol removal. Additionally, the predominant adsorption processes were physisorption and chemisorption. Correlation analyses and characterization data confirmed that pore filling, π-π interactions and surface complexation were the dominant driving forces for phenol adsorption. This research provides an environmentally friendly method for utilizing agricultural wastes for the removal of a variety of pollutions from aquatic environment.

2.
Environ Pollut ; 331(Pt 1): 121871, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37225081

RESUMO

In this study, a novel nitrogen-doped magnetic Fe-Ca codoped biochar for phenol removal was successfully fabricated via a hydrothermal and coactivation pyrolysis method. A series of adsorption process parameters (K2FeO4 to CaCO3 ratio, initial phenol concentration, pH value, adsorption time, adsorbent dosage and ion strength) and adsorption models (kinetic models, isotherms and thermodynamic models) were determined using batch experiments and various analysis techniques (XRD, BET, SEM-EDX, Raman spectroscopy, VSM, FTIR and XPS) to investigate the adsorption mechanism and metal-nitrogen-carbon interaction. The biochar with a ratio of Biochar: K2FeO4: CaCO3 = 3:1:1 exhibited superior properties for adsorption of phenol and had a maximum adsorption capacity of 211.73 mg/g at 298 K, C0 = 200 mg/L, pH = 6.0 and t = 480 min. These excellent adsorption properties were due to superior physicomechanical properties (a large specific surface area (610.53 m2/g) and pore volume (0.3950 cm3/g), a well-developed pore structure (hierarchical), a high graphitization degree (ID/IG = 2.02), the presence of O/N-rich functional groups and Fe-Ox,Ca-Ox, N-doping, as well as synergistic activation by K2FeO4 and CaCO3). The Freundlich and pseudo-second-order models effectively fit the adsorption data, indicating multilayer physicochemical adsorption. Pore filling and π-π interactions were the predominant mechanisms for phenol removal, and H-bonding interactions, Lewis-acid-base interactions, and metal complexation played an important role in enhancing phenol removal. A simple, feasible approach with application potential to organic contaminant/pollutant removal was developed in this study.


Assuntos
Fenol , Poluentes Químicos da Água , Fenol/análise , Nitrogênio/análise , Porosidade , Poluentes Químicos da Água/análise , Fenóis/análise , Carvão Vegetal/química , Adsorção , Cinética , Fenômenos Magnéticos
3.
ACS Appl Mater Interfaces ; 15(17): 21457-21466, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37070714

RESUMO

Understanding the oxygen transport mechanism through an ionomer film that covered the catalyst surface is essential for reducing local oxygen transport resistance and improving the low Pt-loading proton exchange membrane fuel cell performance. Besides the ionomer material, the carbon supports, upon which ionomers and catalyst particles are dispersed, also play a crucial role in local oxygen transport. Increasing attention has been paid to the effects of carbon supports on local transport, but the detailed mechanism is still unclear. Herein, the local oxygen transports based on conventional solid carbon (SC) and high-surface-area carbon (HSC) supports are investigated by molecular dynamics simulations. It is found that oxygen diffuses through the ionomer film that covered the SC supports via "effective diffusion" and "ineffective diffusion". The former denotes the process by which oxygen diffuses directly from the ionomer surface to the Pt upper surface through small and concentrated regions. In contrast, ineffective diffusion suffers more restrictions by both carbon- and Pt-dense layers, and thus, the oxygen pathways are long and tortuous. The HSC supports exhibit larger transport resistance relative to SC supports due to the existence of micropores. Also, the major transport resistance originates from the carbon-dense layer as it inhibits oxygen from diffusing downward and migrating toward the pore opening, while the oxygen transport inside the pore is facile along the pore's inner surface, which leads to a specific and short diffusion pathway. This work provides insight into oxygen transport behavior with SC and HSC supports, which is the basis for the development of high-performance electrodes with low local transport resistance.

4.
J Adhes Dent ; 25(1): 23-30, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689275

RESUMO

PURPOSE: To investigate the bond durability of composite cement to zirconia after treatment with a 15-methacryloyloxypentadecyl dihydrogen phosphate (15-MPDP)-containing adhesive and 2 commercially available adhesives. MATERIALS AND METHODS: Ninety zirconia bars were fabricated and bonded to prepolymerized resin composite cylinders with a composite cement after surface treatment for 20 s using the following adhesives: Adper Easy One (AEO, negative control), Single Bond Universal (SBU, positive control), and 10 wt% 15-MPDP powder mixed with Adper Easy One (15- MPDP). After storage in distilled water at 37°C for 24 h, the specimens were divided into 3 subgroups according to the aging treatment applied (n = 10): no aging treatment (0/TC), 10,000 thermocycles (1/TC), and 37,500 thermocycles (3/TC). Shear bond strength (SBS) was analyzed using two-way ANOVA (p < 0.05), and the fracture surfaces were examined under a dental microscope. RESULTS: Significant differences in the SBSs among the surface treatments and aging treatments were observed (both p < 0.001). The 15-MPDP and SBU groups showed significantly higher SBSs than the AEO group, whereas similar SBSs were found in the 15-MPDP and SBU groups. Significant reductions in the SBSs were found after 37,500 thermocycles (p < 0.001), although no significant difference between specimens aged with 10,000 thermocycles and non-aged specimens was observed. CONCLUSIONS: The 15-MPDP-containing dental adhesive exhibited bond durability comparable to that of a well-established 10-MDP-containing universal adhesive. Aging by 10,000 thermocycles may be insufficient to disrupt the bond of composite cement to zirconia.


Assuntos
Colagem Dentária , Fosfatos , Propriedades de Superfície , Cimentos de Resina , Zircônio , Cimentos de Ionômeros de Vidro , Resistência ao Cisalhamento , Teste de Materiais
5.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499058

RESUMO

Juice, as a liquid foodstuff, is subject to spoilage and damage due to complications during transport and storage. The appearance of intact outer packaging often makes spoilage and damage difficult to detect. Therefore, it of particular importance to develop a fast, real-time material to evaluate liquid foodstuffs. In this paper, starch films with pH response characteristics are successfully prepared by inorganic ion modification by utilizing whole starch and amylopectin as raw materials. The mechanical properties, stability properties, hydrophilic properties and pH electrical signal response indices of the films are analyzed and measured. The films exhibit good electrical conductivity values with 1.0 mL of ion addition (10 mmol/L), causing the composite film to respond sensitively to solutions with varying pH values. In the test of spoiled orange juice, the full-component corn starch (CS) film has more sensitive resistance and current responses, which is more conducive for applications in the quality monitoring of juice. The results indicate that modified starch films can potentially be applied in the real-time monitoring of the safety of liquid foodstuffs.


Assuntos
Sucos de Frutas e Vegetais , Amido , Amido/química , Amilopectina , Embalagem de Alimentos/métodos , Alimentos
6.
Int J Mol Sci ; 23(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36499539

RESUMO

The pyrolysis of biomass is an efficient means of utilizing biomass resources. Biomass can be converted into various high-performance chemicals and functional materials through pyrolysis. However, current pyrolysis technologies suffer from low conversion rates and single products, so the preparation of nitrogen compounds with high economic value remains a challenge. The walnut shell was soaked in three nitrogen-containing compound solutions before carbonization to produce high-value-added nitrogen-containing chemicals (with a nitrogen content of 59.09%) and biochar for the adsorption of polycyclic aromatic hydrocarbons (PAHs). According to biochar analysis, biochar has a porous structure with a specific surface area of 1161.30 m2/g and a high level of rocky desertification. The surface forms a dense pyrrole structure, and the structure produces π-π interactions with naphthalene molecules, exhibiting excellent naphthalene adsorption with a maximum capacity of 214.98 mg/g. This study provides an efficient, rapid, and environmentally friendly method for producing nitrogen-containing chemicals with high-added value and biochar.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/química , Nitrogênio , Pirólise , Carvão Vegetal/química , Adsorção
7.
Medicine (Baltimore) ; 101(31): e30026, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35945710

RESUMO

To investigate the normal diameter of the abdominal aorta and common iliac arteries of the middle-aged and elderly people in China and the relationship of the diameters with age, sex, height, weight, body mass index (BMI), and body surface area (BSA). This retrospective study enrolled 625 patients including 380 males and 245 females aged 60.00 years (interquartile range 13.00 years). All clinical data and the diameters of the abdominal aorta and common iliac arteries were analyzed. The diameter of the abdominal aorta was 21.49 ± 2.49 mm at the proximal, 16.94 (interquartile range 2.39) mm at the middle, and 15.65 (interquartile range 2.90) mm at the distal segment. The diameter of the common iliac artery was 10.76 (interquartile range 1.99) mm at the right proximal, 10.41 (interquartile range 2.05) mm at the left proximal, 10.74 (interquartile range 2.25) mm at the right distal, and 10.67 (interquartile range 2.22) mm at the left distal segment. The height, weight, BSA, BMI, diameters of the proximal, middle and distal abdominal aorta as well as the proximal and distal left and right common iliac arteries were significantly higher in males than those in females (P < .001). Height, weight, BSA, and BMI were significantly (P < .001) positively correlated with the diameter of the abdominal aorta and common iliac artery at the proximal, middle, and distal segments. The middle and distal diameters of the abdominal aorta were significantly higher in males than those in females (P < .05). The diameter of the abdominal aorta at the proximal, middle, and distal segment as well as the diameter of the left and right common iliac artery at the distal segment were significantly (P < .05) increased with age. The normal values of the diameter of the abdominal aorta and common iliac arteries are suggested for the middle-aged and elderly Chinese people for clinical reference. The diameters are gender related and significantly positively correlated with BSA, height, weight, and BMI, which is beneficial for the diagnosis and treatment planning of relevant vascular diseases.


Assuntos
Aorta Abdominal , Artéria Ilíaca , Idoso , Aorta Abdominal/diagnóstico por imagem , Superfície Corporal , China , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Front Bioeng Biotechnol ; 10: 1099118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36686261

RESUMO

The integrity of the packaging of a liquid foodstuff makes it difficult to detect spoilage. Therefore, it is important to develop a sensitive, fast and real-time material for liquid food detection. CMC, as lignocellulose derivatives and starch are widely used in the food industry. In this study, starch films with pH-responsive properties are successfully prepared from full-component starch and corn amylopectin (CA) by adding CMC. The effects of CMC on the mechanical properties, morphology characteristics, physical and chemical structures, stability and pH responsiveness of the starch films are analyzed. The starch/CMC-1.0 g composite films display good electrical conductivity and reduce the resistance of the composite film by two orders of magnitude. The composite films have pH response ability; in the simulation of orange juice spoilage experiment, the CA/CMC composite film has a more sensitive current response and was more suitable for the application to liquid food quality detection. Additionally, the starch/CMC composite films have potential applications for rapid detection and real-time monitoring of the safety of liquid food.

9.
ACS Appl Mater Interfaces ; 13(29): 34332-34340, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34275282

RESUMO

The self-supporting graphdiyne/exfoliated graphene (GDY/EG) composites materials were prepared by the solvothermal method and applied as lithium-ion batteries (LIBs). Graphdiyne (GDY) is a new type of carbon allotrope with a natural macroporous structure, but its conductivity is poor. A small amount of highly conductive graphene can improve surface conductivity and facilitate electron transport. The layered GDY/graphene heterogeneous interface can reduce the electron aggregation polarization, enhance the ability to obtain electrons from the electrolyte, and form a more uniform solid-electrolyte interface (SEI) film. The structural performance and electrochemical performance have been systematically studied. The results showed that the GDY/EG composite electrode has a reversible capacity of 1253 mA h g-1 after 600 cycles at a current density of 0.5 A g-1. When the current density is 5 A g-1, the GDY/EG composite electrode can still maintain a reversible capacity of 324 mA h g-1 after 2000 cycles, and the electrode can still maintain a good morphology after recycling. GDY/EG has a high reversible capacity, excellent rate capability, and cycle stability. A small amount of EG and inner foam copper form a double-layer conductivity, which changes the storage method of lithium ions and facilitates the rapid diffusion of lithium ions.

10.
ACS Omega ; 6(3): 2206-2214, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33521460

RESUMO

Based on the characteristic that Ca2+ can react with 4-ethyl-2-methoxyphenol (EMP) to form a complexation with a phenol-calcium ratio of 4:1, a new extraction and purification method of EMP is developed for the first time in this work. At an optimum purification condition, 99.60% purity of EMP can be obtained through a reaction and decomposition operation. By combining a variety of characterizations, which consist of in situ Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance (NMR), inductively coupled plasma optical emission spectrometer (ICP-OES), gas chromatography-mass spectrometry (GC-MS)/flame ionization detector (FID), elemental analysis, and thermogravimetric analysis, the reaction mechanism of the coordination process is studied. It is demonstrated that there are three stages of the coordination reaction between Ca2+ and EMP. A neutralization reaction occurs in the first stage, while the second stage is a mixing reaction stage including neutralization and coordination reaction. When the reaction proceeds to the third stage, another coordination reaction occurs. Furthermore, phenol and ethanol are added as impurities in EMP. EMP with a purity of more than 99.50% can be obtained using this purification method. It confirms that this efficient method can achieve a good purification effect even for EMP solutions with complicated components.

11.
Mol Med Rep ; 23(4)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33576440

RESUMO

Following the publication of this article and after having solicited the opinions of all the participating authors, the Editorial Office was contacted by the authors to explain that the following changes are required to the list of contributing authors on the paper. The corresponding author of the article should be changed to the first author (Gang Chen), and a request was made that the name of the final author in the author list (Xiaotang Yang), who was also the original corresponding author, be removed. Therefore, the author affiliations and addresses, and the corresponding author information, in this paper have been revised as follows: GANG CHEN1, ZHIFENG ZHENG2, JUNSHENG LI3, PEIGANG ZHANG4, ZHENJUN WANG5, SHIPING GUO1, JUN MA6, JIAN SHEN7 and HUIXIN LI8. 1The Secondary Department of Thoracic Surgery, The Tumor Hospital Affiliated to Shanxi Medical University, Taiyuan, Shanxi 030013; 2Department of General Thoracic Surgery, Linfen People's Hospital, Linfen, Shanxi 041000; 3Department of Cardiothoracic Surgery, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, Zhejiang 318000; 4Department of Cardio­Thoracic Surgery, The People's Hospital of Lvliang, Lvliang, Shanxi 033000; 5Cardiothoracic Surgery Department of Shanxi Yangquan Coal Industry (Group) Co., Ltd., Yangquan, Shanxi 045000; 6Department of Thoracic Surgery, Heji Hospital, Changzhi Medical College, Changzhi, Shanxi 046011; 7Department of Cardiothoracic Surgery, Changzhi People's Hospital Affiliated to Shanxi Medical University, Changzhi, Shanxi 046000; 8Department of Cardiothoracic Surgery, Yuci District People's Hospital, Jinzhong, Shanxi 030600, P.R. China. Correspondence to: Dr Gang Chen, The Secondary Department of Thoracic Surgery, The Tumor Hospital Affiliated to Shanxi Medical University, No. 3 of Workers' New Village, Xinghualing, Taiyuan, Shanxi 030013, P.R. China. E­mail: 1973chengang@163.com. Note that all the authors listed on the paper, including the author who has been removed, Xiaotang Yang, have agreed to this Corrigendum. The authors regret this error in the presentation of these affiliations, and apologize for any inconvenience caused. [the original article was published in Molecular Medicine Reports 23: 212, 2021; DOI: 10.3892/mmr.2021.11851].

12.
ACS Appl Mater Interfaces ; 13(7): 8507-8517, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33570382

RESUMO

A multimetal doping strategy has aroused extensive attention in promoting a non-noble catalyst for selective hydrogenation reaction. Herein, a multimetallic catalyst (NiCoZn@CN) with excellent catalytic performance for hydrogenation of furfural (FAL) to furfuryl alcohol (FOL) is prepared through a facile, inexpensive, and efficient pyrolysis method. Using H2 as a H donor, extremely high selectivity (>99%) with 100% conversion is attained over the optimal NiCoZn@CN-600 catalyst. The subtle synergy between Co and Ni, Zn dopants, which remarkably promotes the performance of the Co-based catalyst, is revealed. In the NiCoZn@CN system, Co0 is proven to be the main active site, whose content is greatly improved by Ni and Co dopants. Additionally, the Ni dopant could also benefit activation of H2 and the Zn dopant could enhance metal nanoparticle dispersion and the porous structure of the catalyst. In situ FTIR indicates that the vertical adsorption mode of FAL with the Oaldehyde terminal on NiCoZn@CN-600 ensures a selective hydrogenation process. With a N-doped carbon matrix, NiCoZn@CN-600 shows good cycling stability in five times run. NiCoZn@CN-600 is also competent in the catalytic transfer hydrogenation (CTH) of FOL, affording >99% yield with 2-propanol as a H donor. This study opens an avenue toward rational design of multimetallic doping catalysts with high selectivity for challenging reactions in the conversion of biomass-derived compounds.

13.
Mol Med Rep ; 23(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33495838

RESUMO

Lung cancer is one of the most common types of cancer and has a high mortality rate, worldwide. The major histopathological subtype is non­small cell lung cancer (NSCLC). The aim of the present study was to investigate the role of long non­coding (lnc) RNA PITPNA antisense RNA 1 (PITPNA­AS1) in NSCLC and elucidate its potential mechanisms. The expression of PITPNA­AS1 was determined in several NSCLC cell lines. Following PITPNA­AS1­silencing, cell proliferation, invasion and migration were evaluated using Cell Counting Kit­8, colony formation, Transwell assay and wound healing assays, respectively. The expression levels of proliferation­, migration­ and epithelial­mesenchymal transition (EMT)­associated proteins were examined using immunofluorescence assay or western blot analysis. A luciferase reporter assay was conducted to verify the potential interaction between PITPNA­AS1 and microRNA(miR)­32­5p. Subsequently, rescue assays were performed to investigate the effects of PITPNA­AS1 and miR­32­5p on NSCLC progression. The results demonstrated that PITPNA­AS1 was highly expressed in NSCLC tissues and cell lines. It was found that PITPNA­AS1 silencing inhibited the proliferation, invasion and migration of NSCLC cells. Furthermore, the protein expression of E­cadherin was upregulated, while the expression levels N­cadherin and vimentin were downregulated. The luciferase reporter assay confirmed that miR­32­5p was a direct target of PITPNA­AS1. The rescue experiments suggested that a miR­32­5p inhibitor significantly reversed the inhibitory effects of PITPNA­AS1 silencing on proliferation, invasion, migration and EMT in NSCLC cells. Collectively, the present results demonstrated that PITPNA­AS1 silencing could suppress the progression of NSCLC by targeting miR­32­5p, suggesting a promising biomarker in NSCLC diagnosis and treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proliferação de Células , Transição Epitelial-Mesenquimal , Inativação Gênica , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Células A549 , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/genética , MicroRNAs/genética , Metástase Neoplásica , RNA Longo não Codificante/genética , RNA Neoplásico/genética
14.
Eur Radiol ; 31(4): 2332-2339, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33000304

RESUMO

OBJECTIVE: To analyze missed rib fractures and proper time for evaluation on CT at different ages and to determine factors that favor missed fractures. METHODS: One hundred patients with rib fractures who underwent CT were classified into three groups according to their age: young, middle-aged, and elderly. CT was performed within 1 to 6 weeks after trauma. The imaging features and temporal changes of rib fractures were analyzed. RESULTS: At the first CT during the initial week, 638 ribs were detected with one or several fractures, overall 838 fractures were confirmed, and 6 were suspected. In the next 2-6 weeks, 47 occult rib fractures were additionally detected. The number of additionally diagnosed fractures was the highest in respectively the 3rd week among younger, 4th week in the middle-aged, and 6th week in the elderly groups. The detection of occult rib fractures was significantly delayed in the middle-aged and elderly groups compared with the young group (p < 0.05). The time to form bony callus was also significantly (p < 0.05) delayed with age, with significantly (p < 0.05) more time needed to form bony callus in the middle-aged (23.8 ± 4.5 days) and elderly (28.48 ± 5.1 days) groups than in the young group (18.0 ± 2.2 days). CONCLUSIONS: Most rib fractures can be detected within the first week after trauma. Detection of occult rib fractures will be delayed with increase of age, and repeated CT scanning should be appropriately postponed in patients at different ages. Trabecula, inner and outer plates, costal angle, and cartilage are the primary locations for occult and subtle fractures which should be carefully evaluated. KEY POINTS: • More rib fractures can be detected on repeated CT scans, especially for subtle and occult rib fractures. • Detection of all rib fractures helps relieve the patient's concerns and determine the degree of personal injury for appropriate evaluation.


Assuntos
Fraturas das Costelas , Ferimentos não Penetrantes , Idoso , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fraturas das Costelas/diagnóstico por imagem , Costelas , Tomografia Computadorizada por Raios X
15.
ACS Appl Mater Interfaces ; 12(31): 35088-35097, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32662620

RESUMO

To understand the processes of voltage cycling-induced catalyst degradation, influence of cycle profiles on Pt degradation is investigated using a mathematical method. Results show that the electrochemical surface area (ECSA) loss rate increases significantly with longer dwell time at the upper potential limit (UPL), which is mainly attributed to the enhanced Pt mass loss. The scan rate is also found to have little impact on the ECSA loss in the range of 1-37.5 mV/s as a lower scan rate will increase the Pt mass loss but mitigate Ostwald ripening. However, too long dwell time at the UPL or too slow scan rate would promote the formation of a more steady-state Pt oxide coverage, which is speculated to mitigate Pt dissolution. Decreasing cycle number has also been demonstrated to be the main contributor to the lower ECSA loss due to Ostwald ripening. Additionally, Ostwald ripening and Pt mass loss have comparable contributions to catalyst degradation at the UPL ≤ 0.9 V, while Pt mass loss contributes more at a higher UPL, which suggests that different load cycling strategies should be proposed for mitigating catalyst degradation at different UPLs.

16.
Adv Sci (Weinh) ; 7(12): 2000286, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32596122

RESUMO

Reverse electrodialysis is a promising method to harvest the osmotic energy stored between seawater and freshwater, but it has been a long-standing challenge to fabricate permselective membranes with the power density surpassing the industry benchmark of 5.0 W m-2 for half a century. Herein, a vertically transported graphene oxide (V-GO) with the combination of high ion selectivity and ultrafast ion permeation is reported, whose permeation is three orders of magnitude higher than the extensively studied horizontally transported GO (H-GO). By mixing artificial seawater and river water, an unprecedented high output power density of 10.6 W m-2 is obtained, outperforming all existing materials. Molecular dynamics (MD) simulations reveal the mechanism of the ultrafast transport in V-GO results from the quick entering of ions and the large accessible area as well as the apparent short diffusion paths in V-GO. These results will facilitate the practical application of osmotic energy and bring an innovative design strategy for various systems involving ultrafast transport, such as filtration and catalysis.

17.
ACS Omega ; 5(17): 10011-10020, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32391489

RESUMO

A mild and effective synthesis of resorcinol-furfural (RF) thermosetting resin was proposed with ethanol as a distinctive solvent, which, as a usually neglected factor, was shown to not only help form a homogeneous reaction system but also observably reduce the energy barriers between the early intermediates and transition states in addition reactions by explicit solvent effects, drawn from theoretical calculation conclusions. Besides, the para-additions on aromatic rings were more dominant than ortho-additions with the same reactants, which affected the final link types of monomers verified by Fourier transform infrared spectroscopy and two-dimensional nuclear magnetic resonance tests. The prepared resin can be assigned to a relatively fast gel speed and a high residual mass (65.25%) after pyrolysis in a N2 atmosphere by adjusting the molar ratios of F to R, and the curing of that was a complex reaction, with a curing temperature around 149 °C and an activation energy of about 49.11 kJ mol-1 obtained by the Kissinger method.

18.
Opt Express ; 28(5): 6102-6122, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32225867

RESUMO

A high-sensitivity ultralow-frequency fiber optic interferometric seismometer using phase feedback control is proposed and demonstrated. The principle of sensitivity improvement using feedback is described, and the characteristics of the seismometer, including the ultralow-frequency vibration sensing with Michelson interferometer with and without feedback control, are analyzed in terms of the amplitude response and phase response. The phase feedback control loop is designed and implemented, and higher sensitivity for very low frequency vibration is achieved. The efficacy of the new approach is demonstrated experimentally, showing that the weak vibration signal originally buried in noise can be observed unambiguously.

19.
RSC Adv ; 11(2): 1115-1123, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35423718

RESUMO

Transition metals (Fe, Co, Ni) supported on activated carbons with different pore diameters (<2 nm, 10 nm, 50 nm) to synthesize carbon nanotubes (CNTS) are first investigated in this study. Through several characteristic analyses, Ni supported on 50 nm activated carbon is verified to be the most efficient catalyst among the samples for CNT growth. The optimum conditions for CNT growth are at a growth temperature of 750 °C with a reaction time of 45 min. Furthermore, a novel purification method for CNTs is proposed, in which KOH and Ca(OH)2 powder are pre-mixed with the crude CNTs and CO2 and N2 gas are introduced into this mixture. When KOH and Ca(OH)2 powder are used at a ratio of 2 : 1 under the atmosphere of CO2 and N2 at the temperature of 750 °C for 1 h, almost all of the amorphous carbon is ablated. Compared with KOH powder, the addition of Ca(OH)2 not only advances the ablation effect, but reduces the damage to CNTs.

20.
Exp Cell Res ; 386(1): 111716, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31734152

RESUMO

BACKGROUND: Emerging evidence demonstrates that epoxyeicosatrienoic acids (EETs) as important active eicosanoids that regulate cardiovascular homeostasis, but the mechanisms underlying its favorable anti-hypertrophic benefits in overpressure model remain obscure. METHODS AND RESULTS: Four weeks after transverse aortic constriction (TAC), TAC mice developed maladaptive cardiac hypertrophy and consequent cardiac failure. Conversely, a cardiotropic adeno-associated viral vector (AAV9) encoding CYP2J2 prevented transverse aortic constriction-induced cardiac hypertrophy with preserved ejection fraction. EET also conferred protection against phenylephrine-induced hypertrophy in H9c2 cardiomyoblasts. Further investigations indicate CYP2J2/EET exerts protection against cardiac hypertrophy through opposing the increase of intracellular Ca2+ level and Ca2+-mediated calcineurin/NFATc3 signaling. Meanwhile, extended myocardial fibrosis in TAC mice was also effectively abolished with the administration of AAV9-2J2. Intriguingly, TAC mice display activated TGF-ß/Samd-3 signaling with decreased Smad-7 expression, whereas AAV9-2J2 attenuated the phosphorylation of Smad-3 without altering TGF-ß expression, whilst preservation of Smad-7. Subsequently, the differentiation of cardiac fibroblasts into myofibroblasts in the presence of TGF-ß1 stimulation was significantly disrupted with EET treatment, accompanied by declined Smad-3 activation and collagen production, whereas inhibition of Smad-7 with SiRNA Smad-7 substantially abrogated these effects of EET on cardiac fibroblasts. CONCLUSIONS: EET has synergistic actions on cardiomyocytes and cardiac fibroblasts, preventing cardiac hypertrophy through inhibition of Ca2+-mediated calcineurin/NFATc3 signaling cascades, and ameliorating myocardial fibrosis dependent on Smad-7. This work further extends the potential mechanisms of EET, providing a novel therapeutic approach for the treatment of pathological remodeling and heart failure.


Assuntos
Ácido 8,11,14-Eicosatrienoico/farmacologia , Calcineurina/metabolismo , Cardiomegalia/prevenção & controle , Cardiotônicos/farmacologia , Fatores de Transcrição NFATC/metabolismo , Proteína Smad7/metabolismo , Ácido 8,11,14-Eicosatrienoico/uso terapêutico , Animais , Cálcio/metabolismo , Cardiomegalia/tratamento farmacológico , Cardiotônicos/uso terapêutico , Linhagem Celular , Células Cultivadas , Citocromo P-450 CYP2J2 , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
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