Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 111
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Eur Arch Otorhinolaryngol ; 281(7): 3535-3545, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38353769

RESUMO

OBJECTIVE: The objectives of this study are twofold: first, to visualize the structure of malformed cochleae through image reconstruction; and second, to develop a predictive model for postoperative outcomes of cochlear implantation (CI) in patients diagnosed with cochlear hypoplasia (CH) and incomplete partition (IP) malformation. METHODS: The clinical data from patients diagnosed with cochlear hypoplasia (CH) and incomplete partition (IP) malformation who underwent cochlear implantation (CI) at Beijing Tongren Hospital between January 2016 and August 2020 were collected. Radiological features were analyzed through 3D segmentation of the cochlea. Postoperative auditory speech rehabilitation outcomes were evaluated using the Categories of Auditory Performance (CAP) and the Speech Intelligibility Rating (SIR). This study aimed to investigate the relationship between cochlear parameters and postoperative outcomes. Additionally, a predictive model for postoperative outcomes was developed using the K-nearest neighbors (KNN) algorithm. RESULTS: In our study, we conducted feature selection by using patients' imaging and audiological attributes. This process involved methods such as the removal of missing values, correlation analysis, and chi-square tests. The findings indicated that two specific features, cochlear volume (V) and cochlear canal length (CDL), significantly contributed to predicting the outcomes of hearing and speech rehabilitation for patients with inner ear malformations. In terms of hearing rehabilitation, the KNN classification achieved an accuracy of 93.3%. Likewise, for speech rehabilitation, the KNN classification demonstrated an accuracy of 86.7%. CONCLUSION: The measurements obtained from the 3D reconstruction model hold significant clinical relevance. Despite the considerable variability in cochlear morphology across individuals, radiological features remain effective in predicting cochlear implantation (CI) prognosis for patients with inner ear malformations. The utilization of 3D segmentation techniques and the developed predictive model can assist surgeons in conducting preoperative cochlear structural measurements for patients with inner ear malformations. This, in turn, can offer a more informed perspective on the anticipated outcomes of cochlear implantation.


Assuntos
Cóclea , Implante Coclear , Aprendizado de Máquina , Humanos , Implante Coclear/métodos , Masculino , Feminino , Cóclea/anormalidades , Cóclea/diagnóstico por imagem , Cóclea/cirurgia , Lactente , Resultado do Tratamento , Pré-Escolar , Orelha Interna/anormalidades , Orelha Interna/cirurgia , Orelha Interna/diagnóstico por imagem , Imageamento Tridimensional , Estudos Retrospectivos , Criança
2.
Angew Chem Int Ed Engl ; 63(6): e202314638, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38009764

RESUMO

Ion-selective membranes are crucial in various chemical and physiological processes. Numerous studies have demonstrated progress in separating monovalent/multivalent ions, but efficient monovalent/monovalent ion sieving remains a great challenge due to their same valence and similar radii. Here, this work reports a two-dimensional (2D) MXene membrane with super-aligned slit-shaped nanochannels with ultrahigh monovalent ion selectivity. The MXene membrane is prepared by applying shear forces to a liquid-crystalline (LC) MXene dispersion, which is conducive to the highly-ordered stacking of the MXene nanosheets. The obtained LC MXene membrane (LCMM) exhibits ultrahigh selectivities toward Li+ /Na+ , Li+ /K+ , and Li+ /Rb+ separation (≈45, ≈49, and ≈59), combined with a fast Li+ transport with a permeation rate of ≈0.35 mol m-2 h-1 , outperforming the state-of-the-art membranes. Theoretical calculations indicate that in MXene nanochannels, the hydrated Li+ with a tetrahedral shape has the smallest diameter among the monovalent ions, contributing to the highest mobility. Besides, the weakest interaction is found between hydrated Li+ and MXene channels which also contributes to the ultrafast permeation of Li+ through the super-aligned MXene channels. This work demonstrates the capability of MXene membranes in monovalent ion separation, which also provides a facile and general strategy to fabricate lamellar membranes in a large scale.

3.
J Am Chem Soc ; 145(27): 14793-14801, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37351897

RESUMO

Metal-organic framework (MOF) membranes have attracted significant research interest in gas separation, but efficient helium (He) separation remains a challenge due to the weak polarizability of He and the intrinsic pore size flexibility of MOFs. Herein, incorporated fullerenes (C60 and C70) were used to tune the crystallographic phase composition of ZIF-8 membranes, thus creating small and fixed apertures for selective He permeation. The fullerene-modified ZIF-8 (C60@ZIF-8 and C70@ZIF-8) membranes contain about 20% of the rigid-lattice ZIF-8_I-43m phase and have been prepared as 200-350 nm thick supported layers through electrochemical synthesis. They show a significantly enhanced molecular sieving for He/N2,CH4 together with a satisfactory He permeance of >200 GPU. Specifically, the He/N2 selectivity of the C70@ZIF-8 membrane is up to 30.4, which is much higher than that of the fullerene-free ZIF-8 membrane (5.1) and nearly an order of magnitude higher than those of other reported He-selective MOF membranes. A continuous long-term gas permeation test over 780 h under dry and humid conditions proved the excellent stability of the fullerene-modified ZIF-8 membranes. The general validity and versatility of the proposed strategy for MOF membrane preparation are also demonstrated by the enhancement of the separation performance of a fullerene-modified ZIF-76 membrane.

4.
Cardiovasc Drugs Ther ; 37(6): 1053-1064, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35171385

RESUMO

OBJECTIVE: As some articles have highlighted the role of microRNA-92a (miR-92a) in myocardial ischemia-reperfusion injury (MI/RI), this article aimed to investigate the effect of miR-92a on Sevoflurane (Sevo)-treated MI/RI via regulation of Krüppel-like factor 4 (KLF4). METHODS: An MI/RI rat model was established by ligating the left anterior descending coronary artery. The cardiac function, pathological changes of myocardial tissues, inflammatory response, oxidative stress and cardiomyocyte apoptosis in MI/RI rats were determined. KLF4 and miR-92a expression was detected in the myocardial tissue of rats, and the target relationship between miR-92a and KLF4 was confirmed. RESULTS: Sevo treatment alleviated myocardial damage, inflammatory response, oxidative stress response, and cardiomyocyte apoptosis, and improved cardiac function in MI/RI rats. miR-92a increased and KLF4 decreased in the myocardial tissue of MI/RI rats. KLF4 was targeted by miR-92a. Downregulation of miR-92a or upregulation of KLF4 further enhanced the effect of Sevo treatment on MI/RI. CONCLUSION: This study suggests that depletion of miR-92a promotes upregulation of KLF4 to improve cardiac function, reduce cardiomyocyte apoptosis and further enhance the role of Sevo treatment in alleviating MI/RI.


Assuntos
MicroRNAs , Traumatismo por Reperfusão Miocárdica , Ratos , Animais , MicroRNAs/metabolismo , Sevoflurano/farmacologia , Sevoflurano/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Fator 4 Semelhante a Kruppel , Miocárdio/patologia , Miócitos Cardíacos , Apoptose
5.
Appl Intell (Dordr) ; : 1-17, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36685641

RESUMO

Sepsis is a life-threatening medical condition that is characterized by the dysregulated immune system response to infections, having both high morbidity and mortality rates. Early prediction of sepsis is critical to the decrease of mortality. This paper presents a novel early warning model called Double Fusion Sepsis Predictor (DFSP) for sepsis onset. DFSP is a double fusion framework that combines the benefits of early and late fusion strategies. First, a hybrid deep learning model that combines both the convolutional and recurrent neural networks to extract deep features is proposed. Second, deep features and handcrafted features, such as clinical scores, are concatenated to build the joint feature representation (early fusion). Third, several tree-based models based on joint feature representation are developed to generate the risk scores of sepsis onset that are combined with an End-to-End neural network for final sepsis detection (late fusion). To evaluate DFSP, a retrospective study was conducted, which included patients admitted to the ICUs of a hospital in Shanghai China. The results demonstrate that the DFSP outperforms state-of-the-art approaches in early sepsis prediction.

6.
Angew Chem Int Ed Engl ; 62(52): e202311138, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37615530

RESUMO

The soaring development of industry exacerbates the shortage of fresh water, making drinking water production an urgent demand. Membrane techniques feature the merits of high efficiency, low energy consumption, and easy operation, deemed as the most potential technology to purify water. Recently, a new type of two-dimensional materials, MXenes as the transition metal carbides or nitrides in the shape of nanosheets, have attracted enormous interest in water purification due to their extraordinary properties such as adjustable hydrophilicity, easy processibility, antifouling resistance, mechanical strength, and light-to-heat transformation capability. In pioneering studies, MXene-based membranes have been evaluated in the past decade for drinking water production including the separation of bacteria, dyes, salts, and heavy metals. This review focuses on the recent advancement of MXene-based membranes for drinking water production. A brief introduction of MXenes is given first, followed by descriptions of their unique properties. Then, the preparation methods of MXene membranes are summarized. The various applications of MXene membranes in water treatment and the corresponding separation mechanisms are discussed in detail. Finally, the challenges and prospects of MXene membranes are presented with the hope to provide insightful guidance on the future design and fabrication of high-performance MXene membranes.

7.
Angew Chem Int Ed Engl ; 62(19): e202302124, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864648

RESUMO

Electrocatalytic N2 reduction reaction (NRR) is recognized as a zero-carbon emission method for NH3 synthesis. However, to date, this technology still suffers from low yield and low selectivity associated with the catalyst. Herein, inspired by the activation of N2 by lithium metal, a highly reactive defective black phosphorene (D-BPene ) is proposed as a lithium-like catalyst for boosting electrochemical N2 activation. Correspondingly, we also report a strategy for producing environmentally stable D-BPene by simultaneously constructing defects and fluorination protection based on topochemical reactions. Reliable performance evaluations show that the fluorine-stabilized D-BPene can induce a high NH3 yield rate of ≈70 µg h-1 mgcat. -1 and a high Faradaic efficiency of ≈26 % at -0.5 V vs. RHE in an aqueous electrolyte. This work not only exemplifies the first stable preparation and practical application of D-BPene , but also brings a new design idea for NRR catalysts.

8.
Angew Chem Int Ed Engl ; 62(45): e202312995, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37713602

RESUMO

Two-dimensional (2D) metal-organic framework (MOF) membranes are considered potential gas separation membranes of the next generation due to their structural diversity and geometrical functionality. However, achieving a rational structure design for a 2D MOF membrane and understanding the impact of MOF nanosheet stacking modes on membrane separation performance remain challenging tasks. Here, we report a novel kind of 2D MOF membrane based on [Cu2 Br(IN)2 ]n (IN=isonicotinato) nanosheets and propose that synergetic stacking modes of nanosheets have a significant influence on gas separation performance. The stacking of the 2D MOF nanosheets is controlled by solvent droplet dynamic behaviors at different temperatures of drop coating. Our 2D MOF nanosheet membranes exhibit high gas separation performances for H2 /CH4 (selectivity >290 with H2 permeance >520 GPU) and H2 /CO2 (selectivity >190 with H2 permeance >590 GPU) surpassing the Robeson upper bounds, paving a potential way for eco-friendly H2 separation.

9.
Angew Chem Int Ed Engl ; 62(13): e202218717, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36728627

RESUMO

The aqueous electrocatalytic reduction of NO3 - into NH3 (NitrRR) presents a sustainable route applicable to NH3 production and potentially energy storage. However, the NitrRR involves a directly eight-electron transfer process generally required a large overpotential (<-0.2 V versus reversible hydrogen electrode (vs. RHE)) to reach optimal efficiency. Here, inspired by biological nitrate respiration, the NitrRR was separated into two stages along a [2+6]-electron pathway to alleviate the kinetic barrier. The system employed a Cu nanowire catalyst produces NO2 - and NH3 with current efficiencies of 91.5 % and 100 %, respectively at lower overpotentials (>+0.1 vs. RHE). The high efficiency for such a reduction process was further explored in a zinc-nitrate battery. This battery could be specified by a high output voltage of 0.70 V, an average energy density of 566.7 Wh L-1 at 10 mA cm-2 and a power density of 14.1 mW cm-2 , which is well beyond all previously reported similar concepts.

10.
Angew Chem Int Ed Engl ; 62(30): e202305695, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37235524

RESUMO

Redox flow batteries have been discussed as scalable and simple stationary energy storage devices. However, currently developed systems encounter less competitive energy density and high costs, restricting their wider application. There is a lack of appropriate redox chemistry, preferably based on active materials that are abundant in nature and show high solubility in aqueous electrolytes. A nitrogen-centered redox cycle operating between the limiting species ammonia and nitrate via an eight-electron redox reaction stayed practically unnoticed, albeit its ubiquity in biological processes. Ammonia or nitrate are world-scale chemicals with high aqueous solubility, and are then comparably safe. We demonstrate here the successful implementation of such a nitrogen-based redox cycle between ammonia and nitrate with eight-electron transfer as a catholyte for Zn-based flow batteries, which continuously worked for 12.9 days with 930 charging-discharging cycles. A very competitive energy density of 577 Wh L-1 can be reached, which is well above most reported flow batteries (e.g. 8 times the standard Zn-bromide battery), demonstrating that the nitrogen cycle with eight-electron transfer can offer promising cathodic redox chemistry for safe, affordable, and scalable high-energy-density storage devices.

11.
Small ; 18(52): e2204951, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36333122

RESUMO

Photodynamic therapy (PDT) has been showing great potential in cancer treatment. However, the efficacy of PDT is always limited by the intrinsic hypoxic tumor microenvironment (TME) and the low accumulation efficiency of photosensitizers in tumors. To address the issue, a multifunctional hollow multilayer nanoplatform (H-MnO2 @TPyP@Bro) comprising manganese dioxide, porphyrin (TPyP) and bromelain (Bro), is developed for enhanced photodynamic therapy. MnO2 catalyzes the intracellular hydrogen peroxide (H2 O2 ) to produce oxygen (O2 ), reversing the hypoxic TME in vivo. The generated O2 is converted into singlet oxygen (1 O2 ) by the TPyP shell under near-infrared light, which can inhibit tumor proliferation. Meanwhile, the Bro can digest collagen in the extracellular matrix around the tumor, and can promote the accumulation of H-MnO2 @TPyP@Bro in the deeper tumor tissue, further improving the therapeutic effect of PDT. In addition, MnO2 can react with the overexpressed glutathione in TME to release Mn2+ . Consequently, Mn2+ not only induces chemo-dynamic therapy based on Fenton reaction by converting H2 O2 into hydroxyl radicals, but also activates the Mn2+ -based magnetic resonance imaging. Therefore, the developed H-MnO2 @TPyP@Bro nanoplatform can effectively modulate the unfavorable TME and overcome the limitations of conventional PDT for cancer diagnostic and therapeutic.


Assuntos
Neoplasias , Fotoquimioterapia , Porfirinas , Humanos , Fotoquimioterapia/métodos , Compostos de Manganês , Porfirinas/farmacologia , Porfirinas/uso terapêutico , Bromelaínas/farmacologia , Bromelaínas/uso terapêutico , Óxidos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Oxigênio/farmacologia , Neoplasias/terapia , Peróxido de Hidrogênio/farmacologia , Microambiente Tumoral
12.
J Oral Maxillofac Surg ; 80(12): 2003-2014, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36100114

RESUMO

PURPOSE: Salivary gland carcinomas (SGCs) can be classified into more than 20 subtypes with various clinical behaviors. The present study aimed to analyze the clinical and pathological features of SGCs and evaluate their long-term prognosis. METHODS: A retrospective cohort study was performed. This study investigated cases of histologically confirmed SGC at the authors' institution from January 1963 to December 2014. Data on sex, age, site, histopathological diagnosis, tumor-node-metastasis classification, postoperative radiotherapy and/or chemotherapy, local and regional recurrence, and distant metastasis (DM) were collected as covariates. The overall survival (OS) rate was analyzed as the outcome. Kaplan-Meier survival analysis and Cox multivariate analysis were used for survival analysis. The cohort was divided into 2 groups-before and after 1989. The clinicopathological characteristics of the 2 groups were compared using the χ2 test. RESULTS: The cohort included 1,637 patients who met the admission criteria and had a male-to-female ratio of 0.9:1. The median age was 47 years (range, 8 months to 86 years). The median follow-up time was 54 months (range, 1-432 months). The majority of the tumors occurred in the parotid gland (35.3%), followed by the palate gland (25.2%). Adenoid cystic carcinoma was the most common tumor type (34.3%), and mucoepidermoid carcinoma (29%) was the second most common type. In the 1,637 patients, the neck lymph node metastasis rate was 8.7% at the first surgery, and the overall DM rate was 14.1%. The 5-, 10-, and 15-year OS rates of the 1,637 cases were 93.1%, 87.2%, and 79.3%, respectively. Comparative analysis before and after 1989 showed statistically significant differences in sex, site, histologic subtype, T classification, local and regional recurrence rate, and radiotherapy (P < .05), while no significant differences were found in age, N classification, M staging, DM, or chemotherapy. CONCLUSIONS: The OS rates of SGC have improved significantly over the past 30 years. This is attributable to an increase in the proportion of patients diagnosed at the early stage and receiving radiotherapy, as this has led to a reduction in the local and regional recurrence rate and, consequently, an improvement in the survival rates.


Assuntos
Carcinoma Adenoide Cístico , Carcinoma Mucoepidermoide , Neoplasias das Glândulas Salivares , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Seguimentos , Estadiamento de Neoplasias , Neoplasias das Glândulas Salivares/cirurgia , Neoplasias das Glândulas Salivares/patologia , Carcinoma Adenoide Cístico/cirurgia , Carcinoma Mucoepidermoide/cirurgia , Carcinoma Mucoepidermoide/patologia , Prognóstico , Taxa de Sobrevida , Glândulas Salivares/patologia
13.
Angew Chem Int Ed Engl ; 61(41): e202206152, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-35768337

RESUMO

Bioinspired asymmetric nanofluidic ion channels with ionic diode behavior that can boost the osmotic energy (so-called blue energy) conversion are highly desirable, especially if they can be easily constructed and modified. Two-dimensional (2D) metal carbides and nitrides, known as MXenes, combine hydrophilic surfaces and tunable surface charge properties, providing a shortcut to prepare asymmetric nanofluidic ion channels. Here, we report a mechanically robust, flexible, and scale-up-friendly asymmetric Ti3 C2 Tx MXene-based ionic diode membrane with a highly rectified current and demonstrate its potential use in reverse electrodialysis osmotic energy conversion. Under the salinity gradient of synthetic seawater and river water, our ionic diode membrane-based generator's power density is 8.6 W m-2 and up to 17.8 W m-2 at a 500-fold salinity gradient, outperforming the state-of-the-art membranes. The design of MXene-based ionic diode-type membrane provides a facile and general strategy in developing large-scale 2D nanofluidics and selective ion transport.


Assuntos
Salinidade , Titânio , Íons , Osmose , Água
14.
Angew Chem Int Ed Engl ; 61(27): e202203170, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35478427

RESUMO

Direct synthesis of N-containing organic compounds from dinitrogen (N2 ) can make synthetic chemistry more sustainable. Previous bottlenecks in lithium-mediated N2 fixation were resolved by loading Li-metal anodes covered with the typical Li+ ion-conducting solid electrolyte interface, which are subsequently allowed to react with N2 . The developed strategy allowed us to reach high Faradaic efficiencies toward Li3 N. These reactive Li3 N were then contacted with acylchlorides. Surface nitride ions are more nucleophilic than amines which direct the two C-N coupling reactions toward formation of imides rather than amides, and an integrated current efficiency of 57-77 % could be realized. This study thereby not only provides a feasible electrochemical Li3 N synthesis, but also delineates an economical and green synthesis of highly valuable N-containing compounds from N2 under mild conditions, just using commercial spare parts and processes from the omnipresent Li battery technology.

15.
J Am Chem Soc ; 143(41): 16902-16907, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34623812

RESUMO

Potassium-sulfur batteries hold practical promise for next-generation batteries because of their high theoretical gravimetric energy density and low cost. However, significant impediments are the sluggish K2S oxidation kinetics and a lack of atomic-level understanding of K2S oxidation. Here, for the first time, we report the catalytic oxidation of K2S on a sulfur host with Co single atoms immobilized on nitrogen-doped carbon. On the basis of combined spectroscopic characterizations, electrochemical evaluation, and theoretical computations, we show a synergistic effect of dynamic Co-S and N-K interactions to catalyze K2S oxidation. The resultant potassium-sulfur battery exhibited high capacities of 773 and 535 mAh g-1 under high current densities of 1 and 2 C, respectively. These findings provide atomic-scale insights for the rational design of highly efficient sulfur hosts.

16.
Angew Chem Int Ed Engl ; 60(41): 22265-22269, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34379858

RESUMO

A two-dimensional (2D) laminar membrane with Li+ selective transport channels is obtained by stacking MXene nanosheets with the introduction of poly(sodium 4-styrene sulfonate) (PSS) with active sulfonate sites, which exhibits excellent Li+ selectivity from ionic mixture solutions of Na+ , K+ , and Mg2+ . The Li+ permeation rate through the MXene@PSS composite membrane is as high as 0.08 mol m-2 h-1 , while the Li+ /Mg2+ , Li+ /Na+ , and Li+ /K+ selectivities are 28, 15.5, and 12.7, respectively. Combining the simulation and experimental results, we further confirm that the highly selective rapid transport of partially dehydrated Li+ within subnanochannels can be attributed to the precisely controlled interlayer spacing and the relatively weaker ion-terminal (-SO3 - ) interaction. This study deepens the understanding of ion-selective permeation in confined channels and provides a general membrane design concept.

17.
Angew Chem Int Ed Engl ; 60(39): 21226-21230, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34296814

RESUMO

The combination of gene therapy and chemotherapy provides a We developed a simple and versatile approach to prepare a series of two-in-one nanodrugs through direct self-assembly of cyanine-labeled single-stranded DNA (Cys-DNA) and different types of drug molecules. Molecular dynamics simulation showed that the Cys introduced into the DNA could enhance the noncovalent interaction between Cys-DNA and drug molecules. More drug molecules were incorporated into Cys-DNA, tending to spontaneously form hybrid Cys-DNA/drug nanosphere. Such nanospheres serve as both carriers and cargoes, excluding the extra use of nontherapeutic excipients and showing ultrahigh drug loading capacity. Following this approach, an antisense oligonucleotides/doxorubicin nanodrug model was constructed, demonstrating the significant synergistic anti-tumor therapeutic effect. As a proof of the concept, our study establishes a simple and reproducible two-in-one nucleic acid-based drug formulation.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Carbocianinas/química , DNA/química , Doxorrubicina/farmacologia , Nanopartículas/química , Oligonucleotídeos Antissenso/farmacologia , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Dinâmica Molecular , Oligonucleotídeos Antissenso/química , Tamanho da Partícula
18.
J Am Chem Soc ; 142(50): 20915-20919, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33270450

RESUMO

Metal-organic framework (MOF) membranes have enormous potential in separation applications. There are several MOF membranes grown on polymer substrates aimed for scale-up, but their brittleness hampers any industrial application. Herein, intergrown continuous polypropylene (PP)-supported ZIF-8 membranes have been successfully synthesized via fast current-driven synthesis (FCDS) within 1 h. The PP-supported ZIF-8 membranes exhibit a promising separation factor of 122 ± 13 for binary C3H6-C3H8 mixtures combined with excellent flexibility behavior. The C3H6/C3H8 separation performance of the PP-supported ZIF-8 membrane was found to be constant after bending the supported ZIF-8 film with a curvature of 92 m-1. This outstanding mechanical property is crucial for practical applications. Moreover, we further synthesized ZIF-8 membranes on various polymer substrates and even polymer hollow fibers to demonstrate the production scalability.

19.
J Am Chem Soc ; 142(21): 9582-9586, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32306728

RESUMO

Separation is one of the most energy-intensive processes in the chemical industry, and membrane-based separation technology helps to reduce the energy consumption dramatically. Supported metal-organic framework (MOF) layers hold great promise as a molecular sieve membrane, yet only a few MOF membranes showed the expected separation performance. The main reasons include e.g. nonselective grain boundary transport or the flexible MOF framework, especially the inevitable linker rotation. Here, we propose a crystal engineering strategy that balances the grain boundary structure and framework flexibility in Co-Zn bimetallic zeolitic imidazolate framework (ZIF) membranes and exploit their contributions to the improvement of membrane quality and separation performance. It reveals that a good balance between the two trade-off factors enabled a "sweet spot" that offers the best C3H6/C3H8 separation factor up to 200.

20.
Angew Chem Int Ed Engl ; 59(22): 8720-8726, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31950586

RESUMO

Membrane-based reverse electrodialysis (RED) is considered as the most promising technique to harvest osmotic energy. However, the traditional membranes are limited by high internal resistance and low efficiency, resulting in undesirable power densities. Herein, we report the combination of oppositely charged Ti3 C2 Tx MXene membranes (MXMs) with confined 2D nanofluidic channels as high-performance osmotic power generators. The negatively or positively charged 2D MXene nanochannels exhibit typical surface-charge-governed ion transport and show excellent cation or anion selectivity. By mixing the artificial sea water (0.5 m NaCl) and river water (0.01 m NaCl), we obtain a maximum power density of ca. 4.6 Wm-2 , higher than most of the state-of-the-art membrane-based osmotic power generators, and very close to the commercialization benchmark (5 Wm-2 ). Through connecting ten tandem MXM-RED stacks, the output voltage can reach up 1.66 V, which can directly power the electronic devices.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA