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1.
Small ; 20(12): e2306563, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37929642

RESUMO

Crystalline carbon nitride (CCN), derived from amorphous polymeric CN, is considered as a new generation of metal-free photocatalyst because of its high crystallinity. In order to further promote the photocatalytic performance of CCN, p-type MnO nanoparticles are in situ synthesized and merged with n-type CCN through a one-pot process to form p-n heterojunction. The formed interfacial electric field between the semiconductors with different work functions efficiently breaks the coulomb interaction between MnO and CCN. The prepared catalysts exhibit drastically increased photocatalytic hydrogen evolution (PHE) activity integrated with oxidation of alkyl and aryl alcohols under irradiation of visible light. In the aqueous solution of benzyl alcohol (BzOH), the hydrogen generation rate over MnO/CCN (39.58 µmol h-1) is nearly 7 times and 37 times that of pure CCN (5.76 µmol h-1) and CN (1.06 µmol h-1), respectively, combining with oxidation of BzOH to benzaldehyde. This work proposes an avenue for in situ construction of a novel 2D material-based S-scheme heterojunction and extends its application in solar energy conservation and utilization.

2.
J Colloid Interface Sci ; 648: 898-906, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37329601

RESUMO

Photocatalytic performance of polymeric carbon nitride (CN) is primarily restricted by limited light utilization and poor charge separation efficiency. To this end, skeleton modification strategy was adopted by attaching thiophene ring and polar nickel complex (NiL) onto CN. The obtained bifunctionalized carbon nitride (TCN-NiL) displayed obviously elevated optical absorption and photoexcited charge separation efficiency. The NiL, with polar structure, plays as active sites like cocatalyst thus exhibited platinum-like H2 evolution activity from water splitting under visible light. The optimized photocatalytic H2 generation rate over TCN-NiL reached 136.7 µmol·h-1 without any cocatalyst, the highest rate reported so far in noble-metal-free CN-based catalysts, which is 5 times of that of CN loaded with 3 wt% Pt. Additionally, the maximum wavelength of performing H2 production capacity over TCN-NiL extends to 550 nm from 450 nm of CN, suggesting an excellent visible light absorption ability. This work provides a way for modifying CN to enhance the photocatalytic activities in a noble metal free system.

3.
Biomed J ; 45(3): 472-481, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35367669

RESUMO

BACKGROUND: The impact of COVID-19 on public health has mandated an 'all hands on deck' scientific response. The current clinical study and basic research on COVID-19 are mainly based on existing publications or our knowledge of coronavirus. However, efficiently retrieval of accurate, relevant knowledge on COVID-19 can pose significant challenges for researchers. METHODS: To improve quality in accessing important literature findings, we developed a novel natural language processing (NLP) method to automatically recognize the associations among potential targeted host organ systems, associated clinical manifestations, and pathways. We further validated these associations through clinician experts' evaluations and prioritize candidate drug targets through bioinformatics network analysis. RESULTS: We found that the angiotensin-converting enzyme 2 (ACE2), a receptor that SARS-CoV-2 required for cell entry, is associated with cardiovascular and endocrine organ system and diseases. Furthermore, we found SARS-CoV-2 is associated with some important pathways such as IL-6, TNF-alpha, and IL-1 beta-induced dyslipidemia, which are related to inflammation, lipogenesis, and oxidative stress mechanisms, suggesting potential drug candidates. CONCLUSION: We prioritized the list of therapeutic targets involved in antiviral and immune modulating drugs for experimental validation, rendering it valuable during public health crises marked by stresses on clinical and research capacity. Our automatic intelligence pipeline also contributes to other novel and emerging disease management and treatments in the future.


Assuntos
COVID-19 , Humanos , Descoberta do Conhecimento , Processamento de Linguagem Natural , Peptidil Dipeptidase A/metabolismo , SARS-CoV-2
4.
J Colloid Interface Sci ; 616: 791-802, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35248966

RESUMO

The development of stable and efficient non-noble metal-based photocatalysts for water splitting is currently a key but challenging process for effective conversion and storage of sustainable energy. Here, we designed a new non-noble metal composite photocatalyst by covalently connecting nickel molecular ligand (NiL) to the graphitized carbon nitride (CN) framework for photocatalytic hydrogen evolution under visible light irradiation. Compared to CN, NiL-modified CN (NiL/CN) shows excellent photogenerated carrier migration rate. Without Pt as a co-catalyst, NiL/CN exhibits high photocatalytic activity (23.4 µmol h-1) with high stability. Experiments and theoretical calculations disclose that ligand-metal charge transfer (LMCT) mechanism plays a key role on the enhancement of photocatalytic activity. This work provides a promising method for future designing low-cost, high-performance photocatalysts for hydrogen production under solar light.

5.
J Colloid Interface Sci ; 596: 75-88, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33838327

RESUMO

Evolution of hydrogen from water by utilizing solar energy and photocatalysts is one of the most promising ways to solve energy crisis. However, designing a cost-effective and stable photocatalyst without any noble metals is of vital importance for this process. Herein, an extremely active molecular complex cocatalyst NiL2(Cl)2 is successfully designed. After being covalently linked to thiophene-embedded polymeric carbon nitride (TPCN), the hybrid catalyst NiL2(Cl)2/TPCN exhibits extraordinary H2 production activity of 95.8 µmol h-1 without Pt (λ ≥ 420 nm), together with a remarkable apparent quantum yield of 6.68% at 450 nm. In such a composite catalyst, the embedded π-electron-rich thiophene-ring not only extends the π-conjugated system to enhance visible light absorption, but also promotes the charge separation through electron-withdrawing effect. It turns out that the CN covalent bonds formed between NiL2(Cl)2 and TPCN skeleton accelerate the transfer of electrons to the Ni active sites. Our finding reveals that the strategy of embedding π-electron-rich compounds to graphitic carbon nitride provides potentials to develop excellent photocatalysts. The strong covalent combination of molecular complexes cocatalyst onto organic semiconductors represents an important step towards designing noble-metal-free photocatalysts with superior activity and high stability for visible light driven hydrogen evolution.

6.
Onco Targets Ther ; 13: 7887-7896, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982274

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is a group of malignant hematopoietic system diseases. Taurine-upregulated gene 1 (TUG1) is a long non-coding RNA that has been associated with human cancers, including AML. However, the role and molecular mechanisms of TUG1 in AML remains to be defined. METHODS: Expression of TUG1 and miR-185 was detected using RT-qPCR. Cell viability and apoptotic rate were measured by MTT assay and flow cytometry, respectively. Glycolysis was determined by commercial glucose and lactate assay kits and Western blot. The target binding between TUG1 and miR-185 was predicted on Starbase online database and confirmed by luciferase reporter assay and RNA immunoprecipitation. RESULTS: TUG1 was upregulated and miR-185 was downregulated in the peripheral blood mononuclear cells of AML specimens and cells (HL-60, KG-1, MOLM-14, and MOLM-13). Both TUG1 knockdown and miR-185 overexpression via transfection could suppress cell viability, glucose consumption, lactate production, and hexokinase 2 expression, but promote apoptotic rate in HL-60 and KG-1 cells. Notably, TUG1 functioned as a sponge of miR-185 by target binding. Moreover, downregulation of miR-185 could partially overturn the effect of TUG1 knockdown on cell proliferation and glycolysis in HL-60 and KG-1 cells. CONCLUSION: Expression of TUG1 was upregulated in AML patients and cells, and its knockdown repressed cell proliferation and glycolysis in AML cells in vitro by targeting miR-185.

7.
J Med Internet Res ; 22(5): e19087, 2020 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-32401210

RESUMO

BACKGROUND: In December 2019, pneumonia cases of unknown origin were reported in Wuhan City, Hubei Province, China. Identified as the coronavirus disease (COVID-19), the number of cases grew rapidly by human-to-human transmission in Wuhan. Social media, especially Sina Weibo (a major Chinese microblogging social media site), has become an important platform for the public to obtain information and seek help. OBJECTIVE: This study aims to analyze the characteristics of suspected or laboratory-confirmed COVID-19 patients who asked for help on Sina Weibo. METHODS: We conducted data mining on Sina Weibo and extracted the data of 485 patients who presented with clinical symptoms and imaging descriptions of suspected or laboratory-confirmed cases of COVID-19. In total, 9878 posts seeking help on Sina Weibo from February 3 to 20, 2020 were analyzed. We used a descriptive research methodology to describe the distribution and other epidemiological characteristics of patients with suspected or laboratory-confirmed SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection. The distance between patients' home and the nearest designated hospital was calculated using the geographic information system ArcGIS. RESULTS: All patients included in this study who sought help on Sina Weibo lived in Wuhan, with a median age of 63.0 years (IQR 55.0-71.0). Fever (408/485, 84.12%) was the most common symptom. Ground-glass opacity (237/314, 75.48%) was the most common pattern on chest computed tomography; 39.67% (167/421) of families had suspected and/or laboratory-confirmed family members; 36.58% (154/421) of families had 1 or 2 suspected and/or laboratory-confirmed members; and 70.52% (232/329) of patients needed to rely on their relatives for help. The median time from illness onset to real-time reverse transcription-polymerase chain reaction (RT-PCR) testing was 8 days (IQR 5.0-10.0), and the median time from illness onset to online help was 10 days (IQR 6.0-12.0). Of 481 patients, 32.22% (n=155) lived more than 3 kilometers away from the nearest designated hospital. CONCLUSIONS: Our findings show that patients seeking help on Sina Weibo lived in Wuhan and most were elderly. Most patients had fever symptoms, and ground-glass opacities were noted in chest computed tomography. The onset of the disease was characterized by family clustering and most families lived far from the designated hospital. Therefore, we recommend the following: (1) the most stringent centralized medical observation measures should be taken to avoid transmission in family clusters; and (2) social media can help these patients get early attention during Wuhan's lockdown. These findings can help the government and the health department identify high-risk patients and accelerate emergency responses following public demands for help.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Mineração de Dados , Pneumonia Viral/epidemiologia , Mídias Sociais , Adolescente , Adulto , Fatores Etários , Idoso , COVID-19 , Criança , Pré-Escolar , China/epidemiologia , Infecções por Coronavirus/complicações , Feminino , Febre/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , SARS-CoV-2 , Adulto Jovem
8.
J Hazard Mater ; 382: 121057, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470300

RESUMO

Zeolitic imidazolate frameworks (ZIFs) possess tremendous potential in various adsorption and catalysis areas for their particular structures. However, the dispersibility and acid stability of ZIFs are important issues hindering their applications. To address these challenges, a transparent polydimethysiloxane (PDMS) coating was constructed to heterogeneously anchor the Cu doped ZIF-67 (Cu/ZIF-67) nanoparticles on melamine sponge surface, achieving a PDMS-coated ZIF three-dimensional composite sponge. Thus PDMS coating could also effectively protect ZIFs from acid damage to prolong the service life of photocatalyticity. It was demonstrated that the composite sponges were able to repeatedly (over 40 cycles) degrade Sudan I dyes with remarkable photocatalytic efficiency (>97%). More importantly, the ion impenetrability of PDMS coating made the ZIFs based composite a longer term catalytic life than unprotected Cu/ZIF-67 under acid condition. Incidentally, due to the introduction of rough ZIFs and hydrophobic PDMS coating, the obtained sponge also exhibits super-hydrophobicity (158.5°), great compressibility and excellent oil/acid water separation performance. We expect that such a polymer coating strategy could act as a novel inspiration for extending the applications and life span of ZIF-based composites.

9.
J Colloid Interface Sci ; 560: 11-20, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31639561

RESUMO

Developing earth-abundant H2-production heterogeneous photocatalysts with robust activity and stability has attracted great interests. Herein, a low-cost photocatalyst was prepared by binding nickel complex covalently from primary amines of chitosan (NiL) onto photosensitive carbon nitride nanosheets (CN) through electrostatic interaction. Introduction of NiL results in more efficient utilization of solar energy, photogenerated electrons' direct transfer and lower overpotential for water reduction. The optimized NiL3-CN photocatalyst shows the highest H2 evolution rate of 346 µmol g-1 h-1 under visible light irradiation and exhibits high stability during test. This work presents great potentials for sustainable conversion of solar energy, and sheds positive light on the development of heterogeneous photocatalysts via anchoring H2-evolving molecule catalysts confined by inexpensive macromolecules onto a semiconductor photosensitizer through a facile and valid method.

10.
J Colloid Interface Sci ; 555: 268-275, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31386995

RESUMO

The photocatalytic activity of graphitic carbon nitride (CN) is mainly restricted by its high recombination rate of charge carriers and narrow visible light absorption. In the present work, nitrogen-deficient CN (NDCCN) nanosheets with high crystallinity were synthesized using molten salt (NaLiCO3) as an etching agent and high-temperature solvent. The electronic structure and energy band levels of the obtained NDCCN are optimized to extend its optical absorption and enhance separation efficiency of photo-generated charge carriers. With these changes, NDCCN displays high photocatalytic activity for hydrogen evolution under visible light illumination (111 µmol h-1), which is 4.6 times of that over pristine CN. This finding opens up a new window to simultaneously decrease nitrogen composition and increase crystallinity of carbon nitride for higher solar-light-driven hydrogen production efficiency.

11.
ACS Appl Mater Interfaces ; 11(16): 14986-14996, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30945844

RESUMO

A facile and simple synthetic route is developed to prepare earth-abundant and noble metal-free hybrid photocatalysts, which are composed of graphitic carbon nitride (CN), nickel complex, and NiO x nanoparticles. Bimolecular nucleophilic substitution reaction was employed to attach a nickel complex onto a graphitic CN framework through covalent bonds to support its high loading and dispersion. NiO x nanoparticles were further incorporated into the catalysts to serve as a hole-transporting medium to improve the separation of photogenerated carriers for higher photocatalytic activity. Both yNiL/CN and yNiL/NiO x/CN exhibit superb H2 evolution activity. The optimum H2 evolution rate of the binary photocatalysts yNiL/CN reaches 303.3 µmol·h-1·g-1, whereas that of the ternary photocatalysts yNiL/NiO x/CN reaches 524.1 µmol·h-1·g-1, and the apparent quantum efficiency reaches 1.46% at 450 nm. This finding reveals that coordination of a nickel complex is significant in promoting photocatalytic performance, and the incorporation of NiO x nanoparticles as a hole-transporting medium is beneficial for separation of the photogenerated charge carriers. The novel hybrid system offers a new horizon for designing transition-metal complex-modified graphitic CN as noble metal-free and highly active photocatalysts for efficient visible light-driven hydrogen generation.

12.
Chem Asian J ; 13(20): 3073-3083, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30098233

RESUMO

In this study, a photocatalyst with a distorted skeleton and synthesized by grafting triamterene onto graphitic carbon nitride (g-C3 N4 ) frameworks was prepared. The pteridine ring of the triamterene-based nitrogen-enriched organic structure functions as a trapped electron site owing to its inductive effect. The benzene ring in triamterene plays an important role in the even dispersion of electrons by a conjugative effect. Redistribution of the intramolecular electronic potential is caused by a synergistic effect between the pteridine and benzene rings of triamterene and promotes separation and migration of the photoinduced charge carriers. After coupling with triamterene, the π electrons of g-C3 N4 are relocated; that is, the intrinsic electronic and band structures of g-C3 N4 are effectively modulated. The modified polymeric photocatalyst shows a high photocatalytic H2 evolution rate of 157.5 µmol h-1 , a value that is 4.3 times higher than the H2 evolution rate of pristine g-C3 N4 (36.8 µmol h-1 ), with an apparent quantum efficiency of 9.7 % at λ=450 nm. The incorporation of triamterene into the g-C3 N4 frameworks significantly expands its π-delocalized system by redistribution of the electronic potential, expands the visible-light absorption range, and effectively promotes the separation and migration of photoinduced charge carriers. This strategy may provide a reference for promoting charge separation of g-C3 N4 through redistribution of the electronic potential and for synthesizing novel carbon nitride based semiconductors for efficient solar energy conversion into hydrogen.

13.
J Colloid Interface Sci ; 526: 374-383, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29751271

RESUMO

This work reports effective photocatalysts which are composed of carbon nitride (CN), carbon nanotubes (CNTs), MoS2 and NiS, for hydrogen evolution aiming at energy crises and environmental pollutions. The morphologies and optical properties of the photocatalysts were carefully characterized and their photocatalytic performance towards water reduction was studied afterwards. MoS2 and NiS exhibit a significant synergistic effect working as co-catalysts. Compared to MoS2/CN nanohybrid, carbon nanotubes and NiS improved the absorption of visible light and the separation of charge carriers effectively. NiS-MoS2/CNTs/CN catalyst exhibits high performance for H2 evolution and the optimized rate is 309.9 µmol·h-1·g-1 with no noble metals under visible light irradiation. The study demonstrates a non-noble metal photocatalyst system for effective generation of hydrogen with low cost.

14.
Small ; 14(12): e1703599, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29430823

RESUMO

Conjugated polymers with tailored donor-acceptor units have recently attracted considerable attention in organic photovoltaic devices due to the controlled optical bandgap and retained favorable separation of charge carriers. Inspired by these advantages, an effective strategy is presented to solve the main obstructions of graphitic carbon nitride (g-C3 N4 ) photocatalyst for solar energy conversion, that is, inefficient visible light response and insufficient separation of photogenerated electrons and holes. Donor-π-acceptor-π-donor polymers are prepared by incorporating 4,4'-(benzoc 1,2,5 thiadiazole-4,7-diyl) dianiline (BD) into the g-C3 N4 framework (UCN-BD). Benefiting from the visible light band tail caused by the extended π conjugation, UCN-BD possesses expanded visible light absorption range. More importantly, the BD monomer also acts as an electron acceptor, which endows UCN-BD with a high degree of intramolecular charge transfer. With this unique molecular structure, the optimized UCN-BD sample exhibits a superior performance for photocatalytic hydrogen evolution upon visible light illumination (3428 µmol h-1 g-1 ), which is nearly six times of that of the pristine g-C3 N4 . In addition, the photocatalytic property remains stable for six cycles in 3 d. This work provides an insight into the synthesis of g-C3 N4 -based D-π-A-π-D systems with highly visible light response and long lifetime of intramolecular charge carriers for solar fuel production.

15.
J Colloid Interface Sci ; 495: 27-36, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28187307

RESUMO

Nitrogen-deficient graphitic carbon nitride (CN-HAc) was synthesized by thermal condensation of acetic acid-treated melamine as a precursor. The nitrogen vacancies play a remarkable role on controlling the electronic structure of g-C3N4, such as extending the optical absorption and enhancing the separation efficiency of photogenerated charge carriers, resulting in the improvement of photocatalytic activity. The photocatalytic activity of the catalysts was evaluated by splitting water and degradation of rhodamine B (RhB) under visible light irradiation (λ>420nm). The average H2 evolution rate on CN-HAc is 24µmolh-1, which is about 5 times of that on pristine g-C3N4. Meanwhile, CN-HAc exhibits superior photocatalytic mineralization of RhB. The possible formation mechanism of nitrogen-deficient in the framework of g-C3N4 is proposed.

16.
Chem Asian J ; 12(5): 515-523, 2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-28028932

RESUMO

Carbonyl-grafted g-C3 N4 porous nanosheets (COCNPNS) were fabricated by means of a two-step thermal process using melamine and oxalic acid as starting reagents. The combination of melamine with oxalic acid to form a melamine-oxalic acid supramolecule as a precursor is key to synthesizing carbonyl-grafted g-C3 N4 . The bulk carbonyl-grafted g-C3 N4 (COCN) was further thermally etched onto porous nanosheets by O2 under air. In such a process, the carbonyl groups were partly removed and the obtained sample showed remarkably enhanced visible-light harvesting and promoted the separation and transfer of photogenerated electrons and holes. With its unique porous structure and enhanced light-harvesting capability, under visible-light illumination (λ>420 nm) the prepared COCNPNS exhibited a superior photocatalytic hydrogen evolution rate of 83.6 µmol h-1 , which is 26 times that of the p-CN obtained directly from thermal polycondensation of melamine.

17.
Phys Chem Chem Phys ; 17(22): 14827-35, 2015 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-25978305

RESUMO

Advanced materials for electrocatalytic and photoelectrochemical water splitting are key for taking advantage of renewable energy. In this study, ZnO/ZnSe/CdSe/Cu(x)S core-shell nanowire arrays with a nanoporous surface were fabricated via ion exchange and successive ionic layer adsorption and reaction (SILAR) processes. The ZnO/ZnSe/CdSe/Cu(x)S sample displays a high photocurrent density of 12.0 mA cm(-2) under AM 1.5G illumination, achieves the highest IPCE value of 89.5% at 500 nm at a bias potential of 0.2 V versus Ag/AgCl, and exhibits greatly improved photostability. The functions of the ZnSe, CdSe, and Cu(x)S layers in the ZnO/ZnSe/CdSe/Cu(x)S heterostructure were clarified. ZnSe is used as a passivation layer to reduce the trapping and recombination of charge carriers at the interfaces of the semiconductors. CdSe functions as a highly efficient visible light absorber and builds heterojunctions with the other components to improve the separation and transportation of the photoinduced electrons and holes. Cu(x)S serves as a passivation layer and an effective p-type hole mediator, which passivates the defects and surface states of the semiconductors and forms p-n junctions with CdSe to promote the hole transportation at the semiconductor-electrolyte interface. The nanoporous surface of the ZnO/ZnSe/CdSe/Cu(x)S core-shell nanowire arrays, together with the tunnel transportation of the charge carriers in the thin films of ZnSe and CdSe, also facilitates the kinetics of photoelectrochemical reactions and improves the optical absorption as well.

18.
ACS Appl Mater Interfaces ; 6(11): 8467-74, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24758144

RESUMO

ZnO/ZnS/CdS/CuInS2 core-shell nanowire arrays with enhanced photoelectrochemical activity under visible light were successfully prepared via ion exchange and hydrothermal methods. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV-vis absorption, X-ray photoemission spectroscopy, and photoelectrochemical response. As a p-n junction photoanode, ZnO/ZnS/CdS/CuInS2 heterostructure shows much higher visible light photoelectrocatalytic activity toward water splitting than ZnO/ZnS/CdS and ZnO/ZnS films. The ZnO/ZnS/CdS/CuInS2 film with optimal constitution exhibits the highest photocurrent of 10.5 mA/cm(2) and the highest IPCE of approximately 57.7% at 480 nm and a bias potential of 0 V versus Ag/AgCl. The critical roles of CdS and ZnS in ZnO/ZnS/CdS/CuInS2 heterostructure were investigated. ZnS, as a passivation layer, suppresses the recombination of the photogenerated charge carriers at the interface of the oxide and CuInS2. CdS enhances the absorption of visible light and forms p-n junctions with CuInS2, which promotes the transport of charge carriers and retards the recombination of electrons and holes in CuInS2 to improve the photoelectrochemical performance of ZnO/ZnS/CdS/CuInS2 heterostructure.

19.
J Biomed Inform ; 48: 130-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24486562

RESUMO

Extracting information from unstructured clinical narratives is valuable for many clinical applications. Although natural Language Processing (NLP) methods have been profoundly studied in electronic medical records (EMR), few studies have explored NLP in extracting information from Chinese clinical narratives. In this study, we report the development and evaluation of extracting tumor-related information from operation notes of hepatic carcinomas which were written in Chinese. Using 86 operation notes manually annotated by physicians as the training set, we explored both rule-based and supervised machine-learning approaches. Evaluating on unseen 29 operation notes, our best approach yielded 69.6% in precision, 58.3% in recall and 63.5% F-score.


Assuntos
Inteligência Artificial , Carcinoma/diagnóstico , Neoplasias Hepáticas/diagnóstico , Processamento de Linguagem Natural , Algoritmos , Carcinoma/patologia , China , Simulação por Computador , Sistemas Computacionais , Mineração de Dados/métodos , Registros Eletrônicos de Saúde , Humanos , Idioma , Neoplasias Hepáticas/patologia , Informática Médica/métodos , Software
20.
Dalton Trans ; 43(9): 3660-8, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24413658

RESUMO

Surface-dispersive-type Bi2O2CO3/Bi2WO6 heterostructured nanosheets were successfully prepared via anion exchange in a hydrothermal process with the graphitic carbon nitride (g-C3N4) as a precursor of CO3(2-). The Bi2O2CO3 nanoparticles (with diameters about 5 nm) were highly homogeneously dispersed and inlaid in the single-crystalline Bi2WO6 nanosheets. The composites with intimate interfacial contacts between Bi2O2CO3 and Bi2WO6 exhibited superior visible light photocatalytic activity towards the degradation of rhodamine B (RhB). The composite nanosheets containing 7.86 wt% Bi2O2CO3 showed the best performance and the degradation rate of RhB was 6 times faster than that with the bare Bi2WO6. The dramatic enhancement of the photocatalytic activity of the Bi2O2CO3/Bi2WO6 photocatalysts can be attributed to the hetero-interfaces between Bi2O2CO3 and Bi2WO6, their intrinsically layered structure, two-dimensional morphology and the effective separation of the photoinduced carriers at the interfaces and in the semiconductors. This method can be used to design and prepare other Aurivillius heterostructured semiconductors for efficient light harvesting and energy conversion applications.

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