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1.
Environ Pollut ; 344: 123269, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38159627

RESUMO

The removal and recovery of uranium [U(VI)] from organic containing wastewater has been a challenging in radioactive wastewater purification. Here, we designed a polyamine/amidoxime polyacrylonitrile fiber (PAN-AO-A) with high removal efficiency, excellent selectivity, excellent organic resistance and low cost by combining the anti-organic properties of amidoxime polyacrylonitrile fiber (PAN-AO-A) with the high adsorption capacity of polyamine polyacrylonitrile fiber, which is used to extract U(VI) from low-level uranium-containing wastewater with high ammonia nitrogen and organic content. PAN-AO-A adsorbent with high grafting rate (86.52%), high adsorption capacity (qe = 618.8 mg g-1), and strong resistance to organics and impurity interference is achieved. The adsorption rate of U(VI) in both real organic and laundry wastewater containing uranium is as high as 99.7%, and the partition coefficients (Kd) are 7.61 × 105 mL g-1 and 9.16 × 106 mL g-1, respectively. The saturated adsorption capacity of PAN-AO-A in the continuous system solution can reach up to 505.5 mg g-1, and the concentration of U(VI) in the effluent is as low as 1 µg L-1. XPS analysis and Density functional theory (DFT) studies the coordination form between U(VI) and PAN-AO-A, where the most stable structure is η2-AO(UO2)(CO3)2. The -NH-/-NH2 and -C(NH2)N-OH groups of PAN-AO-A exhibit a synergistic complex effect in the U(VI) adsorption process. PAN-AO-A is a material with profound influence and limitless potential that can be used for wastewater containing U(VI) and organic matter.


Assuntos
Urânio , Águas Residuárias , Urânio/análise , Poliaminas , Oximas/química , Adsorção
2.
Front Neurosci ; 17: 1057781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845438

RESUMO

Objective: Optic chiasma compression and associated visual impairment induced by a non-functioning pituitary adenoma (NFPA) is commonly assessed by the optic disk and retina but is inadequate to understand the entire visual pathway impairment. We aim to evaluate the use of optical coherence tomography (OCT) coupled with diffusion tensor imaging (DTI) for the preoperative evaluation of visual pathway impairment. Methods: Fifty-three patients with NFPA (categorized into mild and heavy compression subgroups) were subjected to OCT to calculate the thickness of the circumpapillary retinal nerve fiber layer (CP-RNFL), macular ganglion cell complex (GCC), macular ganglion cell layer (GCL), and macular inner plexus layer (IPL), as well as to DTI to calculate the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values. Results: Compared to mild compression, heavy compression caused decreased FA value, increased ADC value of several segments of the visual pathway, thin temporal CP-RNFL, and quadrant macular GCC, IPL, and GCL. Average CP-RNFL thickness, inferior-macular inner-ring IPL and GCC thicknesses, inferior CP-RNFL thickness, and superior CP-RNFL thickness were the best indicators of the impairment of the optic nerve, optic chiasma, optic tract, and optic radiation, respectively. Conclusion: DTI and OCT parameters can effectively evaluate visual pathway impairment and are beneficial for the objective preoperative evaluation of visual pathway impairment in patients with NFPA.

3.
Adv Sci (Weinh) ; 8(8): 2004262, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33898196

RESUMO

Single junction binary all-small-molecule (ASM) organic solar cells (OSCs) with power conversion efficiency (PCE) beyond 14% are achieved by using non-fullerene acceptor Y6 as the electron acceptor, but still lag behind that of polymer OSCs. Herein, an asymmetric Y6-like acceptor, BTP-FCl-FCl, is designed and synthesized to match the recently reported high performance small molecule donor BTR-Cl, and a record efficiency of 15.3% for single-junction binary ASM OSCs is achieved. BTP-FCl-FCl features a F,Cl disubstitution on the same end group affording locally asymmetric structures, and so has a lower total dipole moment, larger average electronic static potential, and lower distribution disorder than those of the globally asymmetric isomer BTP-2F-2Cl, resulting in improved charge generation and extraction. In addition, BTP-FCl-FCl based active layer presents more favorable domain size and finer phase separation contributing to the faster charge extraction, longer charge carrier lifetime, and much lower recombination rate. Therefore, compared with BTP-2F-2Cl, BTP-FCl-FCl based devices provide better performance with FF enhanced from 71.41% to 75.36% and J sc increased from 22.35 to 24.58 mA cm-2, leading to a higher PCE of 15.3%. The locally asymmetric F, Cl disubstitution on the same end group is a new strategy to achieve high performance ASM OSCs.

4.
Oxid Med Cell Longev ; 2021: 6694566, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791073

RESUMO

Over the past few decades, the immune system, including both the adaptive and innate immune systems, proved to be essential and critical to brain damage and recovery in the pathogenesis of several diseases, opening a new avenue for developing new immunomodulatory therapies and novel treatments for many neurological diseases. However, due to the specificity and structural complexity of the central nervous system (CNS), and the limit of the related technologies, the biology of the immune response in the brain is still poorly understood. Here, we discuss the application of novel technologies in studying the brain immune response, including single-cell RNA analysis, cytometry by time-of-flight, and whole-genome transcriptomic and proteomic analysis. We believe that advancements in technology related to immune research will provide an optimistic future for brain repair.


Assuntos
Encéfalo/imunologia , Imunidade , Tecnologia , Encéfalo/metabolismo , Humanos , Proteoma/metabolismo , Análise de Célula Única , Transcriptoma/genética
5.
Drug Deliv ; 26(1): 732-743, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31340678

RESUMO

Multifunctional core-shell nanocarriers based on zinc oxide (ZnO)-gated magnetic mesoporous silica nanoparticles (MMSN) were prepared for cancer treatment through magnetic targeting and pH-triggered controlled drug release. Under an external magnetic field, the MMSN could actively deliver chemotherapeutic agent, daunomycin (DNM), to the targeted sites. At neutral aqueous, the functionalized MMSN could stably accommodate the DNM molecules since the mesopores were capped by the ZnO gatekeepers. In contrast, at the acid intercellular environment, the gatekeepers would be removed to control the release of drugs due to the dissolution of ZnO. Meanwhile, ZnO quantum dots not only rapidly dissolve in an acidic condition of cancer cells but also enhance the anti-cancer effect of Zn2+. An in vitro controlled release proliferation indicated that the acid sensitive ZnO gatekeepers showed well response by the 'on-off' switch of the pores. Cellular experiments against cervical cancer cell (HeLa cells) further showed that functionalized MMSN significantly suppressed cancer cells growth through synergistic effects between the chemotherapy and Zn2+ ions with monitoring the treatment process. These results suggested that the ZnO-gated MMSN platform is a promising approach to serve as a pH-sensitive system for chemotherapies delivery and Zn2+ controlled release for further application in the treatment of various cancers by synergistic effects.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Daunorrubicina/administração & dosagem , Nanopartículas de Magnetita/química , Óxido de Zinco/administração & dosagem , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Sobrevivência Celular , Daunorrubicina/farmacologia , Daunorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Íons , Nanopartículas de Magnetita/administração & dosagem , Porosidade , Pontos Quânticos/química , Dióxido de Silício/química , Óxido de Zinco/farmacologia
6.
ACS Appl Mater Interfaces ; 11(17): 15853-15860, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30987420

RESUMO

A deep highest occupied molecular orbital (HOMO) level is a prerequisite for polymer donor material to boost the organic solar cells (OSCs) performance by achieving high open circuit voltage ( Voc). Abandoning the traditional concept of donor-acceptor (D-A) structure, two copolymers PBTZ-4TC and PBTZ-C4T based on acceptor1-π-acceptor2 (A1-π-A2) architecture, where thiophene as the bridge, the difluorinated benzotriazole (BTZ) as A1 unit alternating copolymerized with 4,4'-dicarboxylate-substituted difluorotetrathiophene (4TC) and 3,3'-dicarboxylate-substituted difluorotetrathiophene (C4T) as A2, respectively, are developed. Because of the double acceptor blocks with high electron affinity, both A1-π-A2 type copolymers possess the lower HOMO levels of 5.52-5.56 eV, which are lower than most D-A type donors. Polymer PBTZ-4TC and PBTZ-C4T have the same backbone but only differ with the position of carboxylate substituent on the A2 unit. Intriguingly, subtle optimizing the position of the carboxylate-substitute causes a significantly difference on the properties of the A1-π-A2 type copolymers. PBTZ-C4T with more planar geometry is demonstrated with better light absorption, higher crystallinity, more pronounced temperature-dependent aggregation effect, and favorable bulk heterojunction morphology but with slightly higher HOMO level and more emission energy loss relative to the PBTZ-4TC. The PBTZ-C4T device exhibits the higher power conversion efficiency (PCE) of 9.34% than the PBTZ-4TC-based one (8.75%). These results reveal that concept of A1-π-A2 type copolymers not only can afford more flexibility in tuning the energy levels to achieve the deep HOMO levels but also can provide a facial strategy to greatly enrich the types of polymer donors for high-performance OSCs.

7.
Macromol Rapid Commun ; 40(8): e1800906, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30779393

RESUMO

A trade-off between open-circuit voltage (V OC ) and high short-circuit (J SC ) becomes one of the most vital problems limiting further improvement in polymer solar cells' (PSCs) efficiency. In this work, two asymmetric polymer donors PBDT-F-2TC and PBDT-SF-2TC are designed and synthesized. When blended with a state-of-the-art acceptor IT-4F with low lowest-unoccupied molecular orbital level, simultaneously high V OC (up to 0.94 V) and J SC (up to 20.73 mA cm-2 ) are obtained for both copolymers. Note that the V OC value of 0.94 V is the highest value of PSCs based on IT-4F reported so far. The simultaneously improved V OC and J SC in resulting devices are discovered from the deep highest-occupied molecular orbital levels (-5.5 to -5.7 eV) and the hyperchromic effect of the polymers, the small driving force, and the small energy loss during the charge transfer, due to the synergistic effect of asymmetric carboxylate unit and fluorine/sulfur atoms. More importantly, thanks to the asymmetric 2TC, both PBDT-F-2TC- and PBDT-SF-2TC-based PSCs can be successfully processed by non-halogenated solvent 1,2,4-trimethylbenzene (TMB) to yield device efficiencies of 10.29% and 10.39%, respectively, which are the maximum values for non-fullerene PSCs fabricated using the eco-friendly solvent TMB.


Assuntos
Fontes de Energia Elétrica , Polímeros/química , Energia Solar
8.
Macromol Rapid Commun ; 39(7): e1700706, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29405489

RESUMO

Main chain donor and side chain acceptor (D-s-A) copolymers are an important branch of the D-A copolymer family. However, the development of D-s-A copolymers significantly falls behind the alternative D-A copolymers, especially for organic solar cells, because a breakthrough in device performance is not yet obtained with a reported power conversion efficiency (PCE) of 2%-4%. Herein, a newly developed D-s-A copolymer PDRCNBDT, bearing 2-(1, 1-dicyanomethylene) rhodanine pendant group as the donor material, delivers a high PCE of 5.3% for nonfullerene solar cells. To the best of our knowledge, this is the best value reported for D-s-A copolymers to date. The improved PCE is observed to be associated with a very small energy loss (Eloss ) of 0.57 eV, accompanied by a high open-circuit voltage (Voc ) of 1.015 eV. It is important to note that this efficient D-s-A copolymer is employed in organic solar cells (OSCs), free of additive and annealing treatments.


Assuntos
Eletricidade , Polímeros/química , Energia Solar , Polímeros/síntese química
9.
Infect Genet Evol ; 38: 62-72, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26705239

RESUMO

Bioactive components in the midgut of ticks play a key role in tick blood digestion, feeding and pathogen transmission. The study of protein and gene targets in midgut provides opportunities to explore novel tick control strategies. Only a few nucleotide sequences are available in public databases for Haemaphysalis flava, an important disease vector for humans and animals. Knowledge of the process of blood digestion by the ticks and protein expression in the digestive tract is limited. Here, we utilize high-throughput sequencing to characterize the midgut transcriptome of fully engorged (FE, average length of 10mm) and partially engorged (PE, average length of 5mm) female H. flava. 6.8GB and 8.3GB of high-quality sequence data were obtained using Illumina sequencing technology. 54,357,490 and 66,116,050 reads were finally assembled into 76,556 unigenes with mean length of 704bp. The transcripts involved in blood meal digestion were classified into eight large categories, including peptidase inhibitor, peptidase (serine-, metallo-, cysteine-, aspartic-peptidase), phospholipase, carbohydrate digestion/hydrolases, lipid binding, immunity-related proteins, iron/heme metabolism and secreted proteins. A total of 5508 differentially expressed genes (DEGs) were identified between FE and PE. To confirm the DEG results, ten genes involved in blood digestion, feeding and defending from pathogens, were validated using qPCR. Our results not only contribute to better understanding of the changes in midgut transcript expression during different blood feeding stages, but also provide a valuable resource for identifying targets for future tick control studies.


Assuntos
Trato Gastrointestinal/metabolismo , Perfilação da Expressão Gênica , Ixodidae/genética , Transcriptoma , Animais , Biologia Computacional , Feminino , Ontologia Genética , Interações Hospedeiro-Patógeno , Repetições de Microssatélites , Anotação de Sequência Molecular , Fases de Leitura Aberta , Análise de Sequência de DNA
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