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1.
J Phys Chem A ; 128(25): 4956-4965, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38868987

RESUMO

Criegee intermediates exert a crucial influence on atmospheric chemistry, functioning as powerful oxidants that facilitate the degradation of pollutants, and understanding their reaction kinetics is essential for accurate atmospheric modeling. In this study, the kinetics of CH2OO and syn-CH3CHOO reactions with acetaldehyde (CH3CHO) were investigated using a flash photolysis reaction tube coupled with the OH laser-induced fluorescence (LIF) method. The experimental results indicate that the reaction of syn-CH3CHOO with CH3CHO is independent of pressure in the range of 5-50 Torr when using Ar as the bath gas. However, the rate coefficient for the reaction between CH2OO and CH3CHO at 5.5 Torr was found to be lower compared to the near-constant values observed between 10 and 100 Torr. Furthermore, the reaction of syn-CH3CHOO with CH3CHO demonstrated positive temperature dependence from 283 to 330 K, with a rate coefficient of (2.11 ± 0.45) × 10-13 cm3 molecule-1 s-1 at 298 K. The activation energy and pre-exponential factor derived from the Arrhenius plot for this reaction were determined to be 2.32 ± 0.49 kcal mol-1 and (1.66 ± 0.61) × 10-11 cm3 molecule-1 s-1, respectively. In comparison, the reaction of CH2OO with CH3CHO exhibited negative temperature dependence, with a rate coefficient of (2.16 ± 0.39) × 10-12 cm3 molecule-1 s-1 at 100 Torr and 298 K and an activation energy and a pre-exponential factor of -1.73 ± 0.31 kcal mol-1 and (1.15 ± 0.21) × 10-13 cm3 molecule-1 s-1, respectively, over the temperature range of 280-333 K.

2.
Sensors (Basel) ; 24(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339668

RESUMO

To address the problem that complex bearing faults are coupled to each other, and the difficulty of diagnosis increases, an improved envelope spectrum-maximum second-order cyclostationary blind deconvolution (IES-CYCBD) method is proposed to realize the separation of vibration signal fault features. The improved envelope spectrum (IES) is obtained by integrating the part of the frequency axis containing resonance bands in the cyclic spectral coherence function. The resonant bands corresponding to different fault types are accurately located, and the IES with more prominent target characteristic frequency components are separated. Then, a simulation is carried out to prove the ability of this method, which can accurately separate and diagnose fault types under high noise and compound fault conditions. Finally, a compound bearing fault experiment with inner and outer ring faults is designed, and the inner and outer ring fault characteristics are successfully separated by the proposed IES-CYCBD method. Therefore, simulation and experiments demonstrate the strong capability of the proposed method for complex fault separation and diagnosis.

3.
Small ; 19(50): e2304918, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37626450

RESUMO

Developing composite materials with the synergistic effects of heterogeneous structures and multiple components is considered as a promising strategy to achieve high-performance electromagnetic wave (EMW) absorbers. To further satisfy the demand of broadband and strong microwave absorption, a novel NiS/carbon nanofibers (CNFs)/porous carbon composite is successfully synthesized by hydrothermal and chemical vapor deposition using lotus leaves as a biomass carbon source. A few carbon nanotubes (CNTs) and uniformly dispersed Ni nanocrystals have also been found in the hybrid. Benefiting from the porous structure derived from lotus leaves, the combination of dielectric NiS, conductive carbon nanomaterials, and magnetic Ni nanoparticles, together with the three-dimensional conductive network of CNFs and CNTs, the remarkable EMW absorption properties with a minimum reflection loss up to -67.65 dB have been achieved at merely 2.32 mm. Besides, the widest effective absorption band can reach 5.9 GHz with a thin thickness of 2.07 mm, covering almost the entire Ku band. In addition, under the incident angle of 31°, the radar cross-section reduction value of LNSF-600 can reach 42.88 dBm2. Therefore, this work provides an efficient and facile method for manufacturing outstanding biomass-derived EMW absorbers.

4.
Small ; 19(41): e2302627, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37287342

RESUMO

The pursuit of efficient CO2 capture materials remains an unmet challenge. Especially, meeting both high sorption capacity and fast uptake kinetics is an ongoing effort in the development of CO2 sorbents. Here, a strategy to exploit liquid-in-aerogel porous composites (LIAPCs) that allow for highly effective CO2 capture and selective CO2 /N2 separation, is reported. Interestingly, the functional liquid tetraethylenepentamine (TEPA) is partially filled into the air pockets of SiO2 aerogel with left permanent porosity. Notably, the confined liquid thickness is 10.9-19.5 nm, which can be vividly probed by the atomic force microscope and rationalized by tailoring the liquid composition and amount. LIAPCs achieve high affinity between the functional liquid and solid porous counterpart, good structure integrity, and robust thermal stability. LIAPCs exhibit superb CO2 uptake capacity (5.44 mmol g-1 , 75 °C, and 15 vol% CO2 ), fast sorption kinetics, and high amine efficiency. Furthermore, LIAPCs ensure long-term adsorption-desorption cycle stability and offer exceptional CO2 /N2 selectivity both in dry and humid conditions, with a separation factor up to 1182.68 at a humidity of 1%. This approach offers the prospect of efficient CO2 capture and gas separation, shedding light on new possibilities to make the next-generation sorption materials for CO2 utilization.

5.
Phys Chem Chem Phys ; 25(34): 23187-23196, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37605796

RESUMO

We have used the OH laser-induced fluorescence (LIF) method to measure the kinetics of the simplest Criegee intermediate (CH2OO) reacting with two abundant amines in the atmosphere: dimethylamine ((CH3)2NH) and trimethylamine ((CH3)3N). Our experiments were conducted under pseudo-first-order approximation conditions. The rate coefficients we report are (2.15 ± 0.28) × 10-11 cm3 molecule-1 s-1 for (CH3)2NH at 298 K and 10 Torr, and (1.56 ± 0.23) × 10-12 cm3 molecule-1 s-1 for (CH3)3N at 298 K and 25 Torr with Ar as the bath gas. Both reactions exhibit a negative temperature dependence. The activation energy and pre-exponential factors derived from the Arrhenius equation were (-2.03 ± 0.26) kcal mol-1 and (6.89 ± 0.90) × 10-13 cm3 molecule-1 s-1 for (CH3)2NH, and (-1.60 ± 0.24) kcal mol-1 and (1.06 ± 0.16) × 10-13 cm3 molecule-1 s-1 for (CH3)3N. We propose that the electronegativity of the atom in the co-reactant attached to the C atom of CH2OO, in addition to the dissociation energy of the fragile covalent bonds with H atoms (H-X bond), plays an important role in the 1,2-insertion reactions. Under certain circumstances, the title reactions can contribute to the sink of amines and Criegee intermediates and to the formation of secondary organic aerosol (SOA).

6.
J Phys Chem A ; 127(11): 2432-2439, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36913641

RESUMO

The kinetics of the simplest Criegee intermediate (CH2OO) reaction with tert-butylamine ((CH3)3CNH2) was studied under pseudo-first-order conditions with the OH laser-induced fluorescence (LIF) method at the temperature range of 283-318 K and the pressure range of 5-75 Torr. Our pressure-dependent measurement showed that at 5 Torr─the lowest pressure measured in the current experiment─this reaction was under the high-pressure limit condition. At 298 K, the reaction rate coefficient was measured to be (4.95 ± 0.64) × 10-12 cm3 molecule-1 s-1. The title reaction was observed to be negative temperature-dependent; the activation energy of (-2.82 ± 0.37) kcal mol-1 and the pre-exponential factor of (4.21 ± 0.55) × 10-14 cm3 molecule-1 s-1 were derived from the Arrhenius equation. The rate coefficient of the title reaction is slightly larger than (4.3 ± 0.5) × 10-12 cm3 molecule-1 s-1 of the CH2OO reaction with methylamine; the electron inductive effect and the steric hindrance effect might play a role in contributing to such difference.

7.
Int J Mol Sci ; 24(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36901862

RESUMO

Primary ovarian insufficiency (POI) is a heterogeneous disease resulting from non-functional ovaries in women before the age of 40. It is characterized by primary amenorrhea or secondary amenorrhea. As regards its etiology, although many POI cases are idiopathic, menopausal age is a heritable trait and genetic factors play an important role in all POI cases with known causes, accounting for approximately 20% to 25% of cases. This paper reviews the selected genetic causes implicated in POI and examines their pathogenic mechanisms to show the crucial role of genetic effects on POI. The genetic factors that can be found in POI cases include chromosomal abnormalities (e.g., X chromosomal aneuploidies, structural X chromosomal abnormalities, X-autosome translocations, and autosomal variations), single gene mutations (e.g., newborn ovary homeobox gene (NOBOX), folliculogenesis specific bHLH transcription factor (FIGLA), follicle-stimulating hormone receptor (FSHR), forkhead box L2 (FOXL2), bone morphogenetic protein 15 (BMP15), etc., as well as defects in mitochondrial functions and non-coding RNAs (small ncRNAs and long ncRNAs). These findings are beneficial for doctors to diagnose idiopathic POI cases and predict the risk of POI in women.


Assuntos
Insuficiência Ovariana Primária , Feminino , Humanos , Recém-Nascido , Amenorreia/genética , Aberrações Cromossômicas , Mutação , Insuficiência Ovariana Primária/genética , Insuficiência Ovariana Primária/patologia
8.
Anal Chem ; 94(40): 13810-13819, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36184789

RESUMO

Since the outbreak of coronavirus disease 2019 (COVID-19), the epidemic has been spreading around the world for more than 2 years. Rapid, safe, and on-site detection methods of COVID-19 are in urgent demand for the control of the epidemic. Here, we established an integrated system, which incorporates a machine-learning-based Fourier transform infrared spectroscopy technique for rapid COVID-19 screening and air-plasma-based disinfection modules to prevent potential secondary infections. A partial least-squares discrimination analysis and a convolutional neural network model were built using the collected infrared spectral dataset containing 857 training serum samples. Furthermore, the sensitivity, specificity, and prediction accuracy could all reach over 94% from the results of the field test regarding 968 blind testing samples. Additionally, the disinfection modules achieved an inactivation efficiency of 99.9% for surface and airborne tested bacteria. The proposed system is conducive and promising for point-of-care and on-site COVID-19 screening in the mass population.


Assuntos
COVID-19 , COVID-19/diagnóstico , Humanos , Análise dos Mínimos Quadrados , Redes Neurais de Computação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
9.
Future Oncol ; 18(17): 2141-2153, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35378998

RESUMO

Background: N6-methyladenosine (m6A) is crucial in cancer and is being intensively studied. Aim: This bibliometric analysis seeks a broad picture of the role of m6A in cancer to guide and broaden future research. Methods: Publications were retrieved from Web of Science Core Collection and PubMed from 2000 to 2021, with keywords 'm6A' and 'cancer', and analyzed in biblioshiny and VOSviewer. Results: A total of 1013 documents were included, and China and the USA were the top countries with close collaboration. Mechanisms and predictive biomarkers of m6A regulator genes were highlighted. Cross-integration of m6A and other research hot spots, including 'immunotherapy', 'hypoxia' and 'polymorphism', were frontiers of m6A in cancer. Conclusion: This bibliometric study offered an updated perspective on m6A in cancer.


Assuntos
Bibliometria , Neoplasias , Adenosina/análogos & derivados , China , Humanos
10.
Environ Sci Technol ; 53(17): 10454-10461, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31403290

RESUMO

Carbon nanomaterials from various sources are the important component of PM2.5 and have many adverse effects on human health. They are prone to interact with other pollutants and subsequently age, defined here as changes in chemical properties. In this work, we investigated the aging process of various carbon nanoparticle samples such as Special Black 4A, Printex U, single-walled carbon nanotubes, and hexane flame soot by ambient air and studied the evolution of their oxidation potential. We found that coatings of inorganic and organic species dominated the aging process of carbonaceous particles by ambient air. The amounts of disordered carbon and C-H functional groups of aged carbonaceous particles decreased during the aging process; meanwhile, the contents of sulfate and nitrate showed significant increases. In addition, the oxidation potential measured by the dithiothreitol assay remarkably declined as a function of aging time with ambient air evidently because of heterogeneous reactions between SO2 and NO2, as well as the coating with organic vapors. This work is important for understanding the oxidation potential changes of carbonaceous particles during atmospheric transport.


Assuntos
Poluentes Atmosféricos , Nanotubos de Carbono , Aerossóis , Ditiotreitol , Monitoramento Ambiental , Humanos , Nitratos , Oxirredução , Tamanho da Partícula , Material Particulado , Fuligem
11.
Phys Chem Chem Phys ; 21(20): 10417-10422, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31066375

RESUMO

Lithium-ion batteries are an attractive power source for a wide variety of applications. Expanding the performance limit of current Li-ion batteries requires ion-solvent interaction, which governs the ion transport behavior of electrolytes, to be fully understood. We herein examine the coordination number of the Li+ ion in LiPF6-PC solutions using femtosecond vibrational spectroscopy. Surprisingly, we found that the coordination number of PC in the first solvation shell of Li+ decreases from 4 to 2 as the salt concentration increases. At dilute salt concentrations, the Li(PC)4+ complex with a tetrahedral geometry is dominant, while at high salt concentrations, the presence of anions in the first solvation shell modifies the solvation structure, leading only 2 PC molecules to coordinate to Li+ directly. The variety of the solvation structure provides a rational explanation for the ionic conductivity changing as the salt concentration increases.

12.
J Environ Sci (China) ; 84: 51-58, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284916

RESUMO

The dithiothreitol (DTT) assay is the most commonly used method to quantify the oxidative potential of fine particles. However, the reported DTT decay rates of carbon black (CB) materials vary greatly among different researchers. This might have resulted from either the intrinsic toxicity of CB or the unsuitability of the DTT assay protocol for CB particles. In the current study, the protocol of the DTT assay for CB materials has been carefully evaluated. It was found that the dispersion degree of CB particles in water has a great influence on the DTT decay rate of CB materials. For CB particles (special black 4A (SB4A) and Printex U) and single-walled carbon nanotube tube (SWCNT), the DTT decay rate after sonication for 10 min became 4.2, 4.6 and 1.7 times higher than that without sonication. The rate continued to grow as a function of ultrasound time up to 30 min of sonication. Although the concentration of soluble transition metals and surface oxygen-containing species such as carbonyls increased slightly with sonication, they had no significant effects on the measured DTT activity, while the increase in the dispersion degree of aggregates was found to play a vital role in the observed enhancement of the DTT decay rates for different CB materials. Based on our results, 30 min of sonication is recommended for sample dispersion when measuring the DTT decay rate of CB materials.


Assuntos
Ditiotreitol , Fuligem/análise , Oxirredução , Sonicação , Fuligem/efeitos da radiação
13.
Ear Nose Throat J ; : 1455613241256520, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808678

RESUMO

Malignant melanoma originating from the sphenoid sinus is an extremely rare but aggressive tumor of the head and neck. A 57-year-old man had a 1 month history of headache, right trigeminal paresthesias, and upper lid ptosis. Magnetic resonance imaging showed a large mass in the right sphenoid sinus and an invasion of the right cavernous sinus and clivus. The patient underwent endoscopic endonasal transsphenoidal surgery, and pathologically revealed malignant melanoma. One month after the operation, the patient was treated with radiation therapy. Unfortunately, the patient died of distant metastasis 2 years later. Due to its rarity, there is still no effective treatment strategy and no way to assess the progression of malignant melanoma.

14.
Nat Commun ; 15(1): 4347, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773146

RESUMO

Epigenetic mechanisms bridge genetic and environmental factors that contribute to the pathogenesis of major depression disorder (MDD). However, the cellular specificity and sensitivity of environmental stress on brain epitranscriptomics and its impact on depression remain unclear. Here, we found that ALKBH5, an RNA demethylase of N6-methyladenosine (m6A), was increased in MDD patients' blood and depression models. ALKBH5 in astrocytes was more sensitive to stress than that in neurons and endothelial cells. Selective deletion of ALKBH5 in astrocytes, but not in neurons and endothelial cells, produced antidepressant-like behaviors. Astrocytic ALKBH5 in the mPFC regulated depression-related behaviors bidirectionally. Meanwhile, ALKBH5 modulated glutamate transporter-1 (GLT-1) m6A modification and increased the expression of GLT-1 in astrocytes. ALKBH5 astrocyte-specific knockout preserved stress-induced disruption of glutamatergic synaptic transmission, neuronal atrophy and defective Ca2+ activity. Moreover, enhanced m6A modification with S-adenosylmethionine (SAMe) produced antidepressant-like effects. Our findings indicate that astrocytic epitranscriptomics contribute to depressive-like behaviors and that astrocytic ALKBH5 may be a therapeutic target for depression.


Assuntos
Homólogo AlkB 5 da RNA Desmetilase , Astrócitos , Transtorno Depressivo Maior , Camundongos Knockout , Animais , Astrócitos/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/genética , Camundongos , Humanos , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/patologia , Masculino , Feminino , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Estresse Psicológico/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Transportador 2 de Aminoácido Excitatório/genética , Comportamento Animal , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Depressão/metabolismo , Depressão/genética , Adulto , Transmissão Sináptica , Pessoa de Meia-Idade
15.
Chemosphere ; 311(Pt 1): 137079, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36328320

RESUMO

In this work, the self-healing polyethersulfone ultrafiltration membrane constructed by host-guest chemistry between cucurbit [8]uril (CB [8] is a family of macrocyclic compounds comprising 8 glycoluril units) and two guest molecules based on reverse thermally induced phase separation (RTIPS) method was developed, which had excellent self-healing performance, better mechanical properties, and high permeation flux and BSA rejection rate. The membrane autonomously restored it BSA rejection rate up to about 89% from rejection rate levels as low as 21% after damage. The observed self-healing performance were attributed to the swelling of pore-filled CB [8] hydrogel into the damage position, the molecular interdiffusion of the hydrogel chains, the strong hydrogen bond of the hydrogel chains and the host-guest interaction between CB [8] and two guest molecules (HEC-Np and PVA-MV). SEM morphologies illustrated that the prepared pore-filled membrane via the RTIPS method had homogeneous and porous skin surface and sponge-like cross-section, which imparted the prepared membranes with improved permeability and better mechanical properties. Properties of MR-CB [8] membranes, which varied with increased content of CB [8], were evaluated by permeability, water contact angle, thermogravimetric analysis (TGA), mechanical properties, FRR, scanning electron microscope (SEM) and atomic force microscopy (AFM). The contact angle water showed that CB [8] hydrogel enhanced the surface hydrophilicity of the prepared membrane. TGA illustrated that the thermal stability improved with the increased content of CB [8]. The optimal pore-filled CB [8] hydrogel membrane (MR-CB [8]2) exhibited that the pure water flux reached 2100.5 L/m2 h, while the BSA rejection rate remained at 86.0%. The results of this work suggested pore-filled CB [8] hydrogel membrane was a more promising way to develop polyethersulfone ultrafiltration membranes with self-healing performance.


Assuntos
Hidrogéis , Ultrafiltração , Água/química
16.
Exp Ther Med ; 25(5): 215, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37123210

RESUMO

The endoscope-assisted supraorbital keyhole approach and extended transsphenoidal approach have been widely used in the treatment of tuberculum sellae meningiomas (TSMs). The purpose of the present study was to retrospectively analyze and compare the characteristics and efficacy of the two surgical approaches under the endoscope in the resection of TSMs. In the present study, 36 patients with TSMs who underwent surgical resection are presented, including one group of 17 cases with an endoscopic supraorbital keyhole approach and the other group of 19 cases with an endoscopic extended transsphenoidal approach. The clinical characteristics, diagnosis, treatment process and treatment effect of the two groups were analyzed retrospectively, and the two surgical approaches were also compared. The gross total resection rates of the two groups were similar, reaching 94.5 and 94.7%, respectively. The postoperative visual acuity recovery showed that in the endoscopic supraorbital keyhole approach group, 23 eyes were improved, 8 eyes were maintained and 3 eyes deteriorated, and the visual recovery was 67.6%. In the endoscopic extended transsphenoidal approach group, 32 eyes were improved, 4 eyes were maintained and 2 eyes deteriorated, and the visual recovery was 84.2%. In the supraorbital keyhole approach group, there was no cerebrospinal fluid leakage, while in the extended transsphenoidal approach group, cerebrospinal fluid leakage occurred in 3 cases (15.8%). In these two groups, no tumor recurrence was revealed during the follow-up of ~5 years. Both the endoscope-assisted supraorbital keyhole approach and the extended transsphenoidal approach were effective and safe. The endoscopic supraorbital keyhole approach treated TSMs with lateral extension, but it was not enough to protect the optic nerve. The endoscopic extended transsphenoidal approach protected the optic nerve, but the risk of cerebrospinal fluid leakage was increased. In conclusion, these two surgical methods have their own advantages and limitations.

17.
ACS Appl Mater Interfaces ; 15(13): 17377-17385, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36952640

RESUMO

The use of amino-terminated siloxanes as coupling interface for perovskite single crystals (PSCs)/silicon integrated devices has been demonstrated to be an effective method toward CMOS compatible optoelectronics; however, it suffers from the coupling stability against the hydrophilicity of the exposed terminal amino groups. In this work, a phenyl-terminated interfacial molecule, anilino-methyl-triethoxysilane (AMTES), is proposed to achieve the effectively galvanic coupling between PSCs and silicon, which can not only improve the device environmental reliability but also lower the surface energy of the silicon substrate so as to facilitate the epitaxial growth of PSCs. Benefiting from the interfacial coupling of AMTES, the obtained MAPbI3 SC/silicon integrated device possesses highly efficient multiwavelength photodetection properties across the X-ray and NIR range, which exhibits a specific detectivity D* of 3.84 × 1013 cm Hz1/2 W-1 in the visible-NIR region and an X-ray sensitivity of 1.18 × 104 µC Gyair-1 cm-2 with the lowest detection limit of 49.6 nGyair s-1. The ultra wide -3 dB bandwidth of 67,300 Hz and the linear dynamic range (LDR) of 112 dB also prove its impressive dynamic response capabilities. Moreover, the AMTES modified integrated device almost maintains 96% of the initial photodetection performance even after keeping in the atmosphere environment for 28 days. This work opens a new avenue for interfacial engineering toward the development of on-chip PSC integrated silicon optoelectronic devices.

18.
Adv Sci (Weinh) ; 10(9): e2205762, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36658735

RESUMO

Aerogel fibers garner tremendous scientific interest due to their unique properties such as ultrahigh porosity, large specific surface area, and ultralow thermal conductivity, enabling diverse potential applications in textile, environment, energy conversion and storage, and high-tech areas. Here, the fabrication methodologies to construct the aerogel fibers starting from nanoscale building blocks are overviewed, and the spinning thermodynamics and spinning kinetics associated with each technology are revealed. The huge pool of material choices that can be assembled into aerogel fibers is discussed. Furthermore, the fascinating properties of aerogel fibers, including mechanical, thermal, sorptive, optical, and fire-retardant properties are elaborated on. Next, the nano-confining functionalization strategy for aerogel fibers is particularly highlighted, touching upon the driving force for liquid encapsulation, solid-liquid interface adhesion, and interfacial stability. In addition, emerging applications in thermal management, smart wearable fabrics, water harvest, shielding, heat transfer devices, artificial muscles, and information storage, are discussed. Last, the existing challenges in the development of aerogel fibers are pointed out and light is shed on the opportunities in this burgeoning field.

19.
Materials (Basel) ; 16(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37959557

RESUMO

Silk nanofibers (SNF) have great applications in high-performance functional nanocomposites due to their excellent mechanical properties, biocompatibility, and degradability. However, the preparation of SNF by traditional methods often requires the use of some environmentally harmful or toxic reagents, limiting its application in green chemistry. In this paper, we successfully prepared SNF using natural silk as raw material and solvent stripping technology by adjusting the solvent concentration and solution ratio (the diameter of about 120 nm). Using the above SNFs as raw materials, SNF membranes were prepared by vacuum filtration technology. In addition, we prepared an SNF/MXene nanocomposite material with excellent humidity sensitivity by simply coating MXene nanosheets with silk fibers. The conductivity of the material can approach 1400.6 S m-1 with excellent mechanical strength (51.34 MPa). The SNF/MXene nanocomposite material with high mechanical properties, high conductivity, and green degradability can be potentially applied in the field of electromagnetic interference (EMI) shielding, providing a feasible approach for the development of functional nanocomposite materials.

20.
Exp Ther Med ; 25(3): 114, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36815971

RESUMO

Thanks to the rapid development and progress of endoscopic technology, the endoscopic endonasal transsphenoidal approach has become one of the best surgical methods for resection of sellar and suprasellar tumors. The craniopharyngioma is usually located in the sellar region or suprasellar region, which is suitable for resection through the endoscopic endonasal transsphenoidal approach. The present report describes 21 cases of craniopharyngioma treated by endoscopic endonasal transsphenoidal approach in the Department of Neurosurgery at the Chongqing General Hospital from February 2014 to September 2019. The characteristics of patients and tumors, including clinical symptoms, preoperative magnetic resonance imaging, intraoperative conditions, as well as postoperative and follow-up outcomes were evaluated. The main clinical symptoms were headache in 15 cases, visual deficiency in 13 cases and growth retardation in two cases. All 21 patients with craniopharyngioma underwent endoscopic endonasal transsphenoidal surgery. Of these, 20 patients achieved gross total resection and one case achieved subtotal resection. After surgery, headache symptoms improved in 11 patients without deterioration and the vision of 11 patients improved without deterioration. The primary postoperative complications were pituitary deficiency in eight cases and permanent diabetes insipidus in five cases. The patients were followed up from one to 52 months post-operation. There was no recurrence in all patients during the follow-up period. The endoscopic endonasal transsphenoidal approach is a safe and effective resection for craniopharyngioma. Moreover, the endoscopic endonasal trans-sphenoidal approach is one of the preferred surgical methods for treatment of sellar or suprasellar tumor.

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