Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
ACS Appl Mater Interfaces ; 16(1): 1749-1756, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38158375

RESUMO

Montmorillonite (MMT) is known as an ion-exchangeable material, and cations between MMT nanosheets are easily exchanged by other cations. In this work, Ca2+, Fe3+, and Al3+ intercalated two-dimensional MMT membranes were developed by ion exchange of pristine MMT membranes (Na+-MMT), and their ion and dye removal abilities were investigated. The d-spacings of hydrated Fe3+ intercalated MMT membrane (Fe3+-MMT) and Al3+ intercalated MMT membrane (Al3+-MMT) were decreased compared with hydrated Na+-MMT membrane due to the stronger electrostatic attraction between Fe3+/Al3+ and negatively charged MMT nanosheets. Ion and dye sieving performances were improved significantly after the intercalation of Ca2+, Fe3+, and Al3+ into MMT membranes. Al3+-MMT membrane with a thickness of 1.17 µm could exclude 94% of Na+, and its ion sieving performance remained stable during a 120-h ion sieving experiment. Moreover, the rejection rate for rhodamine B (RB) reached 94% using an Al3+-MMT membrane with a thickness of 500 nm, and a water permeance of 73 L m-2 h-1 bar-1 was achieved. The excellent ion and dye sieving performances make it promising in the application of desalination and nanofiltration.

2.
J Colloid Interface Sci ; 622: 11-20, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35490614

RESUMO

Generally, electrospun membranes have high mechanical strength, high porosity and low permeation resistance. Although covalent organic frameworks (COFs) have attracted great interest as advanced membrane materials, few works disclosed that the COFs composite membranes were synthesized on electrospun substrates. In this work, the electrospun polyvinylidene fluoride (PVDF) membranes were used as substrates for the preparation of COF composite membranes with graphene oxide and oxidized carbon nanotubes (GO-OCNTs) as an intermediate layer. The COF/GO-OCNTs/PVDF composite membranes were prepared by suction filtering the GO-OCNTs intermediate layer on the electrospun substrate, and then interfacial polymerization of COF layer. After adding the intermediate layer, the water permeance and dye retention rate of the composite COF membrane are both improved. By exploring the reaction parameters in the interfacial polymerization process, the optimized membrane shows that the rejection rate of Coomassle brilliant blue G250 (BBG-250) is about 97.1%, and the water permeability achieves 96.7 L m-2 h-1 bar-1. In addition, the COF/GO-OCNTs/PVDF composite membrane exhibits excellent chemical and mechanical stability. The long-term filtration experiment of the composite membrane shows good water permeation stability. This work provides a method to prepare dense and defect-free COF films on electrospun substrates.

3.
ACS Appl Mater Interfaces ; 13(48): 58076-58084, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34816708

RESUMO

Two-dimensional (2D) membranes as a new type of water filtration membrane have shown great potential in water separation and purification. However, their long-term stability under cross-flow conditions and their antifouling property are two main concerns for practical separation and purification processes. In this work, a strategy of nanoparticle bridges based on amorphous TiO2 is developed to link adjacent WS2 nanosheets on a WS2 membrane surface, leading to a strong membrane surface with excellent stability during 204 h of continuous cross-flow filtration. Moreover, the amorphous TiO2 bridges also form a TiO2/WS2 heterojunction on the WS2 membrane surface, exhibiting an impressive photocatalysis-driving self-cleaning property by pollutant photodegradation. And the flux recovery ratio (FRR) exceeds 95% after three cycles of separation experiments. The excellent long-term stability and photocatalysis-driving self-cleaning property of the WS2/TiO2 membrane provide a new approach to construct robust 2D membranes.

4.
J Hazard Mater ; 398: 122862, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-32473327

RESUMO

With the frequent discharge of wastewater and leakage of oil accidents, it has gained much attention to treat oil and organic pollutants from water. Herein, a facile and environmentally friendly approach is presented to fabricate MgAlZn layered double hydroxide-coated stainless steel mesh (LDH-SSM) via hydrothermal method, which could be used to separate various oil/water mixtures due to its superhydrophilic and underwater superoleophobic property. The as-prepared mesh possesses selective separation performance for oil/water mixtures with separation efficiency higher than 99.2% and high water flux of ∼ 44.5 L m-2 s-1 under gravity-driven force. Such membrane shows an effective separation for oil/water mixtures and recyclability, as well as exhibit excellent superhydrophilicity, making it a prominent candidate for oily water remediation.

5.
ChemSusChem ; 12(1): 275-282, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30430758

RESUMO

Two-dimensional (2D) lamellar membranes consisting of restacked WS2 nanosheets have shown excellent separation properties for water filtration. The stability, antifouling properties, and antibacterial activities of the WS2 laminar membranes were investigated for practical application. We discovered that the separation properties of the WS2 laminar membranes changed slightly after soaking in water for 28 days as well as that of a 45 h-cross-flow filtration, demonstrating an extraordinary operational stability of the WS2 laminar membranes. The remarkable stability is related to the dominant van der Waals interactions between WS2 nanosheets. In addition, the WS2 laminar membranes exhibited excellent antibacterial properties against S. aureus and E. coli with antibacterial rates of 91.3 % and 89.7 %, respectively. These properties of the WS2 laminar membranes make them promising candidates for application in water filtration.

6.
J Colloid Interface Sci ; 505: 38-48, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28558291

RESUMO

Novel ultrafiltration membranes with both superior antibacterial and self-cleaning properties were fabricated. By using a non-solvent induced phase separation method (NIPS), N-halamine epoxide and siloxane were grafted onto the multi-walled carbon nanotubes (N-Si-MWNTs) to fabricate polyvinylidene fluoride (PVDF) hybrid membranes. The membrane morphology was observed under a field emission scanning electron microscopy. The results demonstrated that the PVDF hybrid membranes had an asymmetrical structure, and their hydraulic permeability was evidently enhanced with the addition of modified MWNTs. When compared with the primitive PVDF membrane, the hybrid membranes presented improved surface hydrophilicity. After three ultrafiltration-regeneration cycles with bovine serum albumin as model biofoulant and pure water as detergent, the PVDF hybrid membranes exhibited a high flux recovery ratio (FRR). Furthermore, when compared with other membranes, the membrane containing N-Si-MWNTs displayed the highest FRR value of above 96.5% after the entire fouling and cleaning experiment. The fabricated PVDF/N-Si-MWNTs hybrid membranes had excellent antibacterial efficacy, presenting maximum antibacterial efficacy of 98.0% and 95.6% against Staphylococcus aureus and Escherichia coli, respectively. Thus, the PVDF/N-Si-MWNTs membranes fabricated in this study are environment-friendly with both benign antibacterial and self-cleaning properties.

7.
ACS Appl Mater Interfaces ; 9(18): 15408-15423, 2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28425291

RESUMO

The uniform monodispersed vanadium-doped three-dimensional dendritic mesoporous silica nanospheres (nV-MSNSs) were successfully synthesized in a heterogeneous oil-water biphase stratification reaction system and characterized by several state-of-the-art methods. The synthesized nV-MSNSs were applied to the oxidative dehydrogenation of the propane (ODHP) reaction with the presence of CO2 and exhibited excellent catalytic performances. The results show that the vanadium loading (1.3-8.0 wt %) evidently influences the textural properties, oxidation state, and polymerization degree of vanadium species of nV-MSNSs. The specific surface area (SBET), pore diameter (Dp), and pore volume (Vp) of nV-MSNSs decrease with the loading of vanadium species. The excessively high vanadium loading leads to the slight connection of nanospheres, but does not affect the assembly and growth of the three-dimensional (3D) dendritic channels. The percentage of highly dispersed vanadium VV species gradually increases and attains the maximum value for 5.2V-MSNSs with the loading of vanadium and then decreases with further vanadium addition. The higher-polymerized VOx species gradually generates above 5.2 wt % vanadium content for nV-MSNSs. The lower-polymerized VOx species appear to be more active than the higher-polymerized VOx species. Markedly, the 5.2V-MSNSs exhibit the highest catalytic activity with the initial propane conversion of 58% for the ODHP. The excellent catalytic performance can be maintained after eight reaction-regeneration cycles. The silica mesoporous frameworks can be well preserved in the reaction-regeneration cycles; meanwhile, the highly dispersed vanadium oxide also can be fully recovered after in situ regeneration. Hence, nV-MSNS catalysts exhibit outstanding activity and stability, and it would have a promising application in the DH of alkanes.

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-607357

RESUMO

Objective To obtain suitable hearing screening methods for preschool children.Methods A total of 2025 children aged 2~6 years old in 30 kindergartens in Huangshi City were selected by random sampling method.Acoustic impedance and otoacoustic emission tests(transiently evoked otoacoustic emissions and distortion product otoacoustic emissions) were performed in two stages of preliminary hearing screening.The children who failed the hearing screening needed to do the re-creening with the same methods;the children who failed the rescreening needed to receive audiological tests including ABR, ASSR examination and imaging examinations.Results The total screening pass rate was 94.02%, of which 1 842 passed the preliminary hearing screening(90.96%, 1 842/2 025).The 183 children who failed the preliminary hearing screening received the re-screening, 62 children passed the re-screening(33.88%,62/183).121 children failed the re-screening(5.98%,121/2 025), and finally 72 children(3.56%,72/2 025)were diagnosed with hearing loss, including 47 cases of otitis media,22 cases of sensorineural hearing loss(8 cases were moderate, 4 cases were severe hearing loss,10 cases were profound);18 cases were unilateral hearing loss while 4 cases were bilateral hearing loss.Conclusion Acoustic impedance and otoacoustic emission tests can be used for hearing screening in preschool children.The hearing problems of preschool children in Huangshi City were concentrated mainly in the middle ear secretory otitis media and different degree of sensorineural hearing loss.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-494041

RESUMO

OBJECTIVE To explore the early intervention effect in autism spectrum disorders children with dysaudia. METHODS Three cases of child with language barrier were diagnosed with dysaudia by acoustic impedance test, distortion otoacoustic emission (DPOAE) and short sound auditory brainstem response test (ABR). They were diagnosed with autism pectrum disorders through further test. They were matched with hearing aid, and took speech rehabilitation training, followed-up one year to observe the language communication effect. RESULTS After one year of treatment with hearing aid, both CAP and SIR score increased. CONCLUSION Autism spectrum disorders children with dysaudia can get better language exchange by early intervention with hearing aid and speech rehabilitation training.

10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-747845

RESUMO

To explore the audiological features in children who were sever sensorineural hearing loss infected with rubella virus. There were two cases of rubella virus infection in children who were deaf, they conducted the distortion product otoacoustic emission, ABR and auditory steady-state evoked response (ASSR) examination, then analyzed the results comprehensively. Two patients' mothers were prompted to have infected rubella virus during the early three months pregnant period by history and laboratory tests. The two patients were not detected deafness gene mutation. Audiology results implied the two patients were very severe binaural sensorineural deafness, so they were recommended to equipped with hearing aids and cochlear implant surgery. Early pregnancy women infected with rubella virus can cause very severe offspring sensorineural deafness. The crowd whose mother were suspected to infect with rubella virus in early pregnancy, that should be tracked and detected hearing in order to achieve early detection, early intervention and early treatment.


Assuntos
Criança , Feminino , Humanos , Gravidez , Implante Coclear , Implantes Cocleares , Potenciais Evocados Auditivos , Auxiliares de Audição , Perda Auditiva Neurossensorial , Virologia , Emissões Otoacústicas Espontâneas , Rubéola (Sarampo Alemão) , Vírus da Rubéola , Virulência
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-464832

RESUMO

Objective To study the efficacy of voice therapy combined with Jinsangsanjie pill in patients with vocal nodule .Methods A total of 146 patients with vocal nodes were randomly divided into three groups :45 cases in group A(single Jinsangsanjie pill therapy) ,47 cases in group B(single voice therapy) and 54 cases in group C(voice therapy combined with Jinsangsanjie pill therapy) ,30 healthy adults were as a normal control group .The treatment lasted 1 month .The results were evaluated by voice handicap index ,voice acoustic analysis and electronic laryngo‐scope which were collected before and after 1 month treatments .Results The VHI ,jitter ,shimmer and NNE of all patients were reduced while the MPT was increased after the treatment .The differences were significant (P0 .05) .Conclusion The voice therapy combined with Jinsangsanjie pill in the treatment of vocal nodules is more efficiently ,and can improve patient’s pronunciation features .

12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-247966

RESUMO

<p><b>OBJECTIVE</b>To compare the efficacy and safety of subcutaneous immunotherapy with dermatophagoides pteronyssinus standardized extract given in conventional and cluster immunotherapy schedules for persistent allergic rhinitis.</p><p><b>METHODS</b>One hundred and ten patients with moderate to severe allergic rhinitis caused by dust mites, in accordance with the immunotherapy inclusion criteria, were allocated to receive conventional immunotherapy as group A (n = 57) or cluster immunotherapy as group B (n = 53). In group A, 7 cases were lost to follow-up, the expulsion rate of group A was 12.28%; in group B, 1 case was lost to follow-up, the expulsion rate of group B was 1.89%. Nasal symptom scores, medicine scores and mini rhinoconjunctivitis quality of life questionnaire (Mini RQLQ) were recorded and compared before and after 7 weeks, 15 weeks, 1.0 year, 1.5 years, 2.0 years. All the scores were assessed to evaluate the clinical efficacy, and also the incidence of local and systemic adverse reactions were registered to evaluate the safety. SPSS 19.0 software was used to analyze the data.</p><p><b>RESULTS</b>Nasal symptom scores, medicine scores and Mini RQLQ of both groups were significant lower than those before the treatment (all P < 0.05). Mini RQLQ and nasal symptom scores in cluster group (0.55 ± 0.21,0.57 ± 0.27) were more significantly declined than the conventional group after 7 weeks and 2.0 years of observation (all PMini RQLQ<0.05;nasal symptom scores: 1.41 ± 0.65, 0.83 ± 0.30, t value was 11.344, 5.649, both P < 0.05). The clinical efficiency rate in cluster group (86.5%, 94.2%) were more significantly highter than those (60.0%, 80.0%) in the conventional group after 7 weeks and 2 years of observation (χ(2) value was 9.224, 4.642, both P < 0.05). The medicine scores in cluster group (0.11 ± 0.04) was more significantly declined than conventional group (0.47 ± 0.11) after 7 weeks (t = 27.665, P < 0.05). The incidence of local and systemic adverse reactions during the incremental-dose phase and maintenance-dose phase compared with conventional immunotherapy were not significantly different (P > 0.05).</p><p><b>CONCLUSION</b>The cluster immunotherapy is a safe treatment method which is more effective and faster than conventional immunotherapy to the dust mites caused allergic rhinitis.</p>


Assuntos
Animais , Feminino , Humanos , Masculino , Dermatophagoides pteronyssinus , Imunoterapia , Perda de Seguimento , Medicina , Pyroglyphidae , Qualidade de Vida , Padrões de Referência , Rinite Alérgica , Alergia e Imunologia , Terapêutica , Segurança , Inquéritos e Questionários
13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-748797

RESUMO

OBJECTIVE@#To investigate the clinical effect of nasal packing of pulmicort respules combined withnasopore after endoscopic sinus surgery.@*METHOD@#A total of 30 CRSwNP and CRSsNP patients with bilateral functional endoscopic sinus surgery and finished following up visit were randomly choosed, conventionally select the left nasal cavity as the experimental group, the right nasal cavity as the control group. Experimental group to pack the nasal cavity with pulmicort respules union nasopore after surgery and control group to pack the nasal cavity with only nasopore after surgery. The differences were observed in patients with subjective symptoms and recovery of mucosa of operative cavity between the two groups after two weeks, one month and three months.@*RESULT@#(1) The postoperative VAS symptoms score about nasal obstruction, nasal secretion, headache, dizziness and distending pain after two weeks,one month and three months in the experiment group were significantly better than those in the control group(P0.05).@*CONCLUSION@#The application of nasal packing of pulmicort respules combined with nasopore after functional endoscopic sinus surgery can effectively relieve postoperative uncomfortable symptoms, promote recovery of mucosa of perative cavity, which deserves clinical promotion.


Assuntos
Humanos , Anti-Inflamatórios , Bandagens , Budesonida , Endoscopia , Epistaxe , Cavidade Nasal , Obstrução Nasal , Seios Paranasais , Cirurgia Geral , Período Pós-Operatório
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...