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1.
J Hazard Mater ; 421: 126634, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34330077

RESUMO

Developing sheet-on-sheet (2D/2D) heterostructure with built-in electric field (BIEF) is effective in boosting the performance of photocatalysts for emerging contaminants degradation. Herein, the 2D/2D microtopography and (-)TiO2/(+)Bi2MoO6 BIEF were precisely integrated into hierarchical nanosheets, which can provide the basis and driving force for charge transfer both in in-plane and interface of heterojunction. The prepared photocatalyst (TiO2/Bi2MoO6) showed high-efficiency and stable performance for photocatalytic amoxicillin (AMX) degradation, which was 18.2 and 5.7 times higher than TiO2 and Bi2MoO6, respectively. More importantly, TiO2/Bi2MoO6 showed more efficient photocatalytic activity and photogenerated charge separation than TiO2@Bi2MoO6 (different morphology). Besides, four possible pathways of AMX degradation were proposed depending on Gaussian calculations and intermediates analysis by GC-MS and HPLC-TOFMS. This work sheds light on the design and construction of unique 2D/2D heterostructure photocatalysts for AMX degradation.


Assuntos
Amoxicilina , Bismuto , Catálise , Molibdênio , Titânio
2.
J Colloid Interface Sci ; 605: 648-656, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34352445

RESUMO

Pancake-like TiO2 (M-TiO2) derived from the metal-organic framework was inlaid into three-dimensional flower-like BiOI through a facile solvothermal method. M-TiO2 supplies large surface area and mesoporous structure for attachment and transfer of the substrates and products, while BiOI acts as a photosensitizer to absorb visible light and generates electrons and holes. The distinct structure of M-TiO2/BiOI gives a favorable contact between the two monomers, and promotes the transfer of charge carriers. In conjunction with the proper band positions of M-TiO2 and BiOI, the efficient separation of electron-hole pairs is attained. Benefiting from the above cooperative effects of M-TiO2 and BiOI, the performance for the vanillin generation from sodium lignosulfonate (SLS) over M-TiO2/BiOI composites has a prominent improvement under visible light. Specifically, the yield over optimal M-TiO2/BiOI sample is about 5.8 mg/gSLS, obviously superior to that over pristine M-TiO2 (~1 mg/gSLS) and BiOI (~1.1 mg/gSLS). It is found that h+ and O2- play the key role for vanillin generation from sodium lignosulfonate, and the low vanillin generation under UV-vis light sheds light on that OH is an adverse factor. We hoped that this work could inspire the studies on the photocatalytic valorization of biomass using noble metal-free catalysts.


Assuntos
Bismuto , Estruturas Metalorgânicas , Benzaldeídos , Luz , Lignina/análogos & derivados , Sódio , Titânio
3.
J Colloid Interface Sci ; 605: 727-740, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34365309

RESUMO

Developing durable photocatalysts with highly efficient antibiotics degradation is crucial for environment purification. Herein, tetra (4-carboxyphenyl) porphyrin (TCPP) was loaded onto the surface of Bi2MoO6 microspheres to gain hierarchical organic-inorganic TCPP/Bi2MoO6 (TCPP/BMO) heterojunctions via a facile impregnation strategy. The catalytic properties of these catalysts were comprehensively investigated through the photodegradation of tetracycline hydrochloride (TC) under visible light. Among all the TCPP/BMO heterojunctions, the highest photodegradation rate constant (0.0278 min-1) was achieved with 0.25 wt% TCPP (TCPP/BMO-2), which was approximately 1.15 folds greater than that of pristine Bi2MoO6 and far superior to pure TCPP. The extremely high photocatalytic performance is attributed to the interfacial interaction between TCPP and Bi2MoO6, which favors the efficient separation of charge carriers and the enhancement of visible-light absorbance. TCPP/BMO-2 possesses high mineralization capability and good recycling performance. Photo-induced O2-, h+, and OH were mainly responsible for the degradation of TC. The degradation pathways of TC and toxicity of degradation intermediates were analyzed based on the intermediates detected by the high performance liquid chromatography-mass spectrometer (HPLC-MS) and the toxicity assessment by the quantitative structure-activity relationship (QSAR) prediction. A possible photocatalytic mechanism over TCPP/BMO is proposed. This work offers an insight in developing the porphyrin-based organic-inorganic heterojunctions for effectively remedying pharmaceutical wastewater.


Assuntos
Porfirinas , Tetraciclina , Antibacterianos/farmacologia , Bismuto , Molibdênio
4.
J Colloid Interface Sci ; 607(Pt 2): 1717-1729, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34598029

RESUMO

This work describes the synthesis of porous hierarchical microspheres composed of amorphous SiO2 and crystalline ß-Bi2O3 (BSO) via a simple solvothermal process and subsequent calcination. Complementary physicochemical methods were applied to study the function of amorphous SiO2, as well as the phase composition and morphology evolution of as-synthesized samples as a function of calcination temperature. The presence of amorphous SiO2 contributed to form hierarchically structured ß-Bi2O3 with enhanced thermostability. Moreover, the degradation of tetracycline hydrochloride (TC) under visible light irradiation was employed as a model reaction to evaluate the photocatalytic activity of as prepared materials. In consequence, both phase composition and morphology were found to be significant parameters for adjusting the photocatalytic performance of the synthesized samples. The fastest TC degradation at a low dosage of catalyst (0.2 g L-1) was observed for the sample annealed at 400℃ which contains a highly crystalline ß-Bi2O3 phase. The synergistic effect of the porous structure, excellent light absorption, and higher charge carrier separation and transfer efficiency is believed to be the reason for the optimal photocatalytic activity. This study offers a new method toward the fabrication of hierarchical porous structured ß-Bi2O3 with enhanced thermostability for various applications.


Assuntos
Bismuto , Dióxido de Silício , Antibacterianos , Microesferas , Porosidade
5.
Chemosphere ; 286(Pt 2): 131783, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34364228

RESUMO

Two-dimensional (2D) bismuth-based semiconductors have aroused intensive concern owing to their prominent photocatalytic activity for organic pollutants removal. In this work, a facile strategy for introducing oxygen vacancy in Bi-based oxyiodides (BixOyIz) sheet-like architectures to activate molecular oxygen was proposed. The structure, photoelectric properties and visible light (λ > 420 nm) induced photocatalytic activities of these samples for decomposition of bisphenol A (BPA) were systematically characterized and evaluated. The as-prepared Bi7O9I3 with a feeding Bi/I molar ratio of 1:1 exhibited the best photocatalytic activity comparable to those of similarly synthesized Bi7O9I3 with other molar ratios and BiOIO3 catalysts. The optimal Bi7O9I3 achieved excellent photocatalytic activity with 99.6 % degradation efficiency of BPA within 20 min and superior structural stability with 95.1 % degradation retention over 5 cycling tests. In addition, the resulting Bi7O9I3 sample displayed a high mineralization efficiency of BPA. Importantly, the plenty of oxygen vacancies (Vos) exsiting in Bi7O9I3 played the dominant role in both accelerating electron transfer and activating molecular oxygen to facilitate the generation of superoxide radical (O2·-) and singlet oxygen (1O2), thereby proceeding oxidative degradation of BPA molecules during photoreactions. The efforts and attempts are also extendable to synthesis other 2D photocatalysts, providing potential for effective charge-carrier separation and molecular oxygen activation.


Assuntos
Compostos Benzidrílicos , Oxigênio , Bismuto , Iodetos , Luz , Óxidos , Fenóis
6.
J Colloid Interface Sci ; 607(Pt 1): 269-280, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34506999

RESUMO

Tetragonal/orthorhombic-bismuth tungstate (t/o-Bi2WO6) homojunctions of high photocatalytic efficiencies were fabricated through a novel in situ Bi induced phase transformation. The photocatalytic efficiencies of t-Bi2WO6 were greatly enhanced via formation of the homojunction. Photocatalytic degradation of rhodamine B (RhB), a recalcitrant organic pollutant, under simulated sunlight illumination was investigated as a demonstration for the efficiency enhancement. A 6.22 folds improvement was achieved with formation of the homojunction in terms of reaction rate constants. The homojunction catalyst was demonstrated to be photocatalytically stable over a five cycles operation. The t/o-Bi2WO6 homojunction enhances separation and utilization efficiency of photo-generated charge carriers and thus greatly boosts the catalytic efficiency. Trapping tests and electron spin resonance spectroscopy were conducted to reveal that singlet oxygen (1O2), hole (h+), electrons (e-), and superoxide anion radical (O2-) are the main working reactive species for RhB degradation. Density functional theory (DFT) calculations were performed to prove the feasibility of Bi induced phase transformation of t-Bi2WO6 to o-Bi2WO6. The present development offers a new design route for high efficiency photocatalysts for water pollution control.


Assuntos
Poluentes Ambientais , Compostos de Tungstênio , Bismuto , Luz
7.
J Colloid Interface Sci ; 607(Pt 1): 423-430, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34509116

RESUMO

For semiconductor-based photocatalytic reactions, defect engineering has been proven as an efficient approach to enhance the photocatalytic performance. In this work, a synergistically PVP/EG-assisted in situ self-assembly strategy has been successfully developed for preparing flowerlike BiOCl nanospheres (NSP) assembled by ultrathin nanosheets (thickness of 3.8 nm) with abundant oxygen vacancies (OVs). During the hydrothermal process, PVP plays a template role in controlling the orientation of the crystallite growth, leading to the forming of nanosheets. Meanwhlie, ethylene glycol would induce the self-assembly of nanosheets into a loose hierarchical architecture duo to its stereo-hindrance effect. NSP achieves a twice higher photocatalytic conversion of benzylamine than BiOCl nanosheets (NST) under visible light. XPS, ESR, NH3-TPD results manifest that NSP possesses more active sites including OVs and unsaturated Bi atoms than NST, because of avoiding the accumulation of ultrathin nanosheets. In situ FTIR reveals that benzylamine molecules can be chemisorbed and activated on BiOCl interfaces via forming -N…Bi- species. The OVs can facilitate the forming of superoxide radicals (•O2-), achieving the selective photooxidation. Finally, a possible synergetic mechanism based on the interaction of reactants and catalyst interfaces was proposed to illustrate the photocatalytic process at the molecular level.


Assuntos
Bismuto , Nanosferas , Catálise , Luz , Oxigênio
8.
J Colloid Interface Sci ; 607(Pt 1): 684-697, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34530189

RESUMO

Persulfate-assisted photocatalysis technology is considered to be a promising method for the rapid and efficient degradation of organic pollutants in water environment remediation. In this study, a novel g-C3N4/Bi2MoO6/PDS (CN/BMO/PDS) system is constructed and applied in 2,4-dinitrophenylhydrazine (2,4-DPH) degradation under visible light irradiation. Compared with the CN/BMO system, the degradation rate of 2,4-DPH is significantly improved from 59.7% to 90.2% within 60 min in the combined CN/BMO/PDS system. The enhanced performance can be attributed to the superior synergetic effects of CN/BMO, PDS and visible light irradiation. More importantly, singlet oxygen (1O2) is determined as the main reactive species based on the radical scavenging experiments and electron paramagnetic resonance (EPR), which indicates that the combined system can achieve non-radical oxidative degradation of pollutants, instead of the traditional radical oxidation process. In addition, the active sites of the reaction during the non-radical 1O2 oxidation are calculated by density functional theory (DFT), and the stability and reusability of catalyst are also investigated. In brief, the CN/BMO/PDS system has great application potential for removing organic pollutants from wastewater.


Assuntos
Poluentes Ambientais , Nanocompostos , Bismuto , Molibdênio
9.
J Colloid Interface Sci ; 607(Pt 2): 942-953, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34571315

RESUMO

A hollow core-shell potassium phosphomolybdate (KMoP)@cadmium sulfide (CdS)@bismuth sulfide (Bi2S3) Z-scheme tandem heterojunction is fabricated by a simple hydrothermal strategy and kept in a water bath to continue the reaction. At the same time, the ternary structure combined Keggin-type polyoxometalate with two photosensitive sulfide semiconductors to form a stable hollow core-shell heterojunction. KMoP@CdS@Bi2S3 with a narrow band gap of âˆ¼ 1.2 eV also has excellent photothermal performance, which may further promote photocatalytic efficiency. The hollow core-shell KMoP@CdS@Bi2S3 tandem heterojunction shows excellent H2 production performance, CrVI reduction ability and photocatalytic degradation performance of highly toxic tetracycline (TC). Under visible light irradiation, the photocatalytic H2 generation rate of the KMoP@CdS@Bi2S3 tandem heterojunction reaches 831 µmol h-1, which is 103 times higher than that of pristine KMoP. The photocatalytic reduction efficiency of CrVI and degradation efficiency of TC are as high as 95.5 and 97.51%, ∼4 times higher than that of KMoP. The boosted photocatalytic performance can be ascribed to the formation of core-shell Z-scheme tandem heterojunctions favoring spatial charge separation and the narrow band gap, which extends the photoresponse to visible light/NIR regions. When TC and CrVI exist at the same time, the reduction efficiency of CrVI can be as high as 99.64% because the intermediate of TC degradation can promote the reduction of CrVI. In addition, the photocatalytic performance of the KMoP@CdS@Bi2S3 heterojunction remains nearly constant after 4 recycles, which indicates high stability. The design strategy may provide new insights for preparing other high-performance core-shell tandem heterojunction photocatalysts for solar energy conversion.


Assuntos
Cádmio , Potássio , Bismuto , Compostos de Cádmio , Catálise , Molibdênio , Ácidos Fosfóricos , Sulfetos
10.
Chemosphere ; 286(Pt 1): 131541, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34293565

RESUMO

To effectively degrade organic pollutants in wastewater, visible-light-driven Bi2MoO6/PPy hierarchical heterogeneous photocatalysts were prepared through a solvothermal method and the following in-situ chemical oxidation polymerization. Compared with pristine Bi2MoO6 photocatalyst, the composite photocatalysts exhibited dramatically improved photocatalytic activity and photostability towards the degradation of methylene blue dye and tetracycline antibiotic. Bi2MoO6/PPy-80 sample achieved the highest photocatalytic degradation rates for methylene blue dye (93.6%) and tetracycline antibiotic (88.3%) under visible light irradiation. These two organic pollutants could be completely degraded into nontoxic small molecules according to in-depth HPLC-MS analysis of degradation products. The transient photocurrent responses, electrochemical impedance spectra, and photoluminescence spectra demonstrated that the introduction of PPy nanoparticles on the surface of Bi2MoO6 nanosheets could effectively accelerate the separation of photo-generated electron-hole pairs. Furthermore, a possible synergetic photocatalytic mechanism was put forward based on the electron spin resonance and XPS valence-band spectra. This work indicated that construction of hierarchical composite photocatalysts combining polypyrrole conductive polymer and Bi2MoO6 semiconductor in nanoscale is an efficient approach to improve photocatalytic activity for environmental remediation.


Assuntos
Poluentes Ambientais , Polímeros , Bismuto , Catálise , Descontaminação , Microesferas , Molibdênio , Pirróis
11.
J Colloid Interface Sci ; 606(Pt 2): 1261-1273, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492464

RESUMO

Constructing a p-n heterojunction is a feasible strategy to manipulate the dynamic behaviors of photogenerated carriers through an internal electric field. Herein, a novel highly efficient indium oxide/bismuth oxyiodide (In2O3/BiOI) p-n junction photocatalyst was fabricated using a facile ionic liquid-assisted precipitation method for the first time. The morphologies were modified by adding different amounts of acetic acid solution. Their hierarchical architecture was beneficial for adsorbing contaminants in wastewater, while the in-situ formed p-n heterojunction between BiOI and In2O3 facilitated interfacial charge transfer and improved the quantum efficiency. Their visible light-responsive photocatalytic activities were systematically investigated by photocatalytic o-phenylphenol (OPP) and 4-tert-butylphenol (PTBP) oxidation. The degradation rate of OPP over In2O3/BiOI-2 was up to 5.67 times higher than that for BiOI. The excellent activity of In2O3/BiOI should be attributed to the rapid interfacial charge transfer, depressed carrier recombination, and proper band potentials. Trapping experiments and electron paramagnetic resonance characterizations confirmed the generation of hydroxyl radicals (•OH) and superoxide radicals (•O2-), which have played a key role in decomposing pollutants. The intermediate products generated during the photocatalytic degradation of OPP were detected and identified by liquid chromatography-mass spectrometry. Meanwhile, their possible molecular structures and degradation pathways have also been inferred.


Assuntos
Poluentes Ambientais , Líquidos Iônicos , Estruturas Metalorgânicas , Bismuto , Catálise , Índio
12.
J Colloid Interface Sci ; 606(Pt 2): 1715-1728, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34500170

RESUMO

The major challenges of clean energy and environmental pollution have resulted in the development of photocatalysis technologies for energy conversion and the degradation of refractory pollutants. Herein, a novel CdSe/Se/BiOBr hydrangea-like photocatalyst was used to produce hydrogen peroxide (H2O2) and degrade ciprofloxacin (CIP). The Z-scheme heterojunction structure of the photocatalyst and the doping of selenium (Se) led to the efficient separation of electron-hole pairs and charge transfer. The optimized sample of 2 wt% CdSe/Se/BiOBr produced 142.15 mg·L-1 rate of H2O2, which was much higher than that produced by pure BiOBr (89.4 mg·L-1) or CdSe/Se (10.9 mg·L-1). Additionally, almost 100 % of CIP was degraded within 30 min, with a first order rate constant of nearly 5.35 times that of pure BiOBr and 81.44 times that of pure CdSe/Se. The excellent removal efficiency of CIP from natural water matrices confirmed that the composites are promising for the removal of contaminants from natural waterways. Based on trapping experiments, electron spin resonance spectra (ESR) spectroscopy, and density functional theory (DFT) calculations, the photocatalytic mechanisms of H2O2 and CIP degradation by the Z-scheme CdSe/Se/BiOBr composites were proposed. Overall, the dual-functional CdSe/Se/BiOBr composite could potentially be applied for photocatalytic production of H2O2 and treatment of organic pollutants in water.


Assuntos
Compostos de Cádmio , Compostos de Selênio , Selênio , Bismuto , Catálise , Ciprofloxacina , Peróxido de Hidrogênio
13.
J Colloid Interface Sci ; 606(Pt 2): 1998-2010, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34749447

RESUMO

The self-assembled Bi-based metal-organic framework microspheres (Bi-MOF-M) by nanorods were successfully constructed by the glycol-assisted solvothermal method. Using Bi-MOF-M as a homologous template, a petal-like Bi2MoO6 (BMO) layer was grown in situ on its surface to facilely construct a chemically bonded heterojunction interface, realizing a micro/nano hierarchical flower spherical-like Bi-MOF-M/BMO heterojunction composite photocatalyst. The as-prepared series of Bi-MOF-M/BMO-x catalysts show higher visible light catalytic performance for tetracycline hydrochloride (TC) degradation. Among them, Bi-MOF-M/BMO-0.3 has the optimal catalytic activity, and the degradation efficiency can reach 93.6% within 60 min of light irradiation with superior mineralization ability and structural stability, and the degradation kinetic constant is 6.12 times that of Bi-MOF-M and 5.69 times that of BMO, respectively. The homologously grown Bi-MOF-M/BMO chemically bonded heterojunction not only effectively broadens the spectral absorption range and enhances the absorption intensity but also promotes the efficient separation of photogenerated carriers through forming a favorable interfacial electric field and well-matched energy band alignment. A reasonable mechanism for the visible light degradation of TC by the Bi-MOF-M/BMO composite catalyst with h+ and 1O2 as the main reactive species is proposed. The micro/nano hierarchical structure of the Bi-MOF/BMO catalyst allows it to exhibit the easy recovery advantage of micron-scale materials while maintaining the high catalytic activity of the primary nano-components.


Assuntos
Estruturas Metalorgânicas , Tetraciclina , Bismuto , Flores , Luz , Microesferas , Molibdênio
14.
J Environ Manage ; 300: 113777, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34649309

RESUMO

Herein, a green and facile methodology was used for the structural design of semiconductor nanomaterials and employed as efficient photocatalyst to resolve the environmental issues of water pollutants. Titanium oxide coupled with bismuth oxide (TiO2@Bi2O3) nanocomposite was synthesized by employing the seed extract of Sapindus mukorossi (commonly found plant in India) and subsequently used for the elimination of toxic, and persistence industrial pollutants namely bisphenol A (BPA) and methylene blue (MB). Microscopic and spectroscopic techniques revealed particle size of synthesized nanocomposite found less than 50 nm along with high crystallinity. Appearance of stretching vibrations at 459 cm-1 for Bi-O-Ti in the IR spectra of nanocomposite has established the coupling of TiO2 with Bi2O3. The parameters of degradation were optimized by varying the pollutant concentration, catalytic amount and pH in the presence of natural sunlight. The nanocomposite TiO2@Bi2O3 showed maximum degradation (MB: 94% and BPA: 91%) at a minimum concentration of pollutant (50 mgL-1) with catalyst amount (35 mg), neutral pH and reduces half-life of pollutants (BPA: 1h, MB: 0.5h). Owing of higher surface area (80 m2g-1), lower band gap (2.5 eV), and more negative zeta potential value (-40.3 mV) results into excellent photocatalytic properties. The breakage of S-N conjugated system in MB results into rapid degradation as compare to BPA. The degradation followed first-order kinetics and Langmuir adsorption in both the cases. Presence of active radicals during the photocatalysis process was responsible for quick degradation and strongly supported by scavenger analysis. GC-MS analysis revealed the degradation of toxic pollutants into safer metabolites and finally mineralized. Multiple times (n = 8) reusability of green photocatalyst advocated sustainability and appropriate for industrial applications.


Assuntos
Poluentes Ambientais , Nanocompostos , Poluentes Químicos da Água , Bismuto , Catálise , Cinética , Fotólise , Titânio
15.
Sensors (Basel) ; 21(20)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34696121

RESUMO

This work reports the fabrication of integrated electrochemical fluidic paper-based analytical devices (ePADs) using a marker pen drawing and screen-printing. Electrodes were deposited on paper using screen-printing with conductive carbon ink. Then, the desired fluidic patterns were formed on the paper substrate by drawing with a commercial hydrophobic marker pen using an inexpensive computer-controlled x-y plotter. The working electrode was characterized by cyclic voltammetry and scanning electron microscopy. The analytical utility of the electrochemical PADs is demonstrated through electrochemical determination of Pb(II) and Cd(II) by anodic stripping voltammetry. For this purpose, the sample was mixed with a buffer solution and a Bi(III) solution, applied to the test zone of the PAD, the metals were preconcentrated as a bismuth alloy on the electrode surface and oxidized by applying an anodic potential scan. The proposed manufacturing approach enables the large-scale fabrication of fit-for-purpose disposable PADs at low cost which can be used for rapid on-site environmental monitoring.


Assuntos
Cádmio , Chumbo , Bismuto , Carbono , Eletrodos
16.
Artigo em Inglês | MEDLINE | ID: mdl-34682434

RESUMO

Novice nurses' successful transition to practice is impacted by their interactions with senior nurses. Ensuring that novice nurses are adequately supported during their transition to practice has wide-ranging and significant implications. The aim of this study is to explore the communication patterns between novice and senior nurses by applying an interaction analysis technique. Trimonthly onboarding evaluations between novice and senior nurses were recorded. The Roter Interaction Analysis System was adapted and deployed to identify communication patterns. In total, twenty-two interactions were analyzed. Senior nurses spoke more (64.5%). Task-focused exchange was predominant amongst senior (79.7%) and novice (59.5%) nurses. Senior nurses' talk was concentrated in clusters of information-giving (45%) and advice or instructions (17.2%), while emotional expression (1.4%) and social talk (0.4%) were rare. Novice nurses' talk was concentrated in clusters-information giving (57%) and positive talk (39.5%). The communication patterns between senior and novice nurses during the onboarding period indicate aspects of novice nurse transition that could be addressed, such as encouraging novice nurses to use these interactions to communicate more, or emphasizing the importance of social talk. These insights can be used to inform mentorship and preceptorship training to ensure that senior nurses are able to adequately support novice nurses through all parts of the transition to practice period.


Assuntos
Enfermeiras e Enfermeiros , Preceptoria , Bismuto , Comunicação , Humanos , Mentores
17.
Zhonghua Nei Ke Za Zhi ; 60(11): 977-981, 2021 Nov 01.
Artigo em Chinês | MEDLINE | ID: mdl-34689518

RESUMO

Objective: To analyze the impact of previous exposure to macrolide, quinolones and nitroimidazole antibiotics on eradication rate of bismuth quadruple therapy (BQT) in newly diagnosed patients with Helicobacter pylori(H. pylori). Methods: A total of 469 patients with H. pylori initially treated at the Third Hospital of Peking University from September 2017 to August 2020 were retrospectively recruited. The therapeutic regimens were BQT containing clarithromycin/levofloxacin/metronidazole recommended by Chinese guidelines. Clinical data were collected, including general demographic data, exposure history of antibiotics, CYP2C16 metabolic pattern, endoscopic diagnosis, bacterial density, H.pylori resistance, eradication results, etc. Univariate analysis, Chi-square test, Fisher exact probability test, Kruskal-Wallis H test and Logistic regression model were used as statistical methods. Results: Among different eradication therapies, univariate and multivariate analyses suggested that previous exposure to macrolides (OR=3.37,95%CI 1.04-10.98, P<0.05) was relevant to the decreased eradication rate of BQT containing clarithromycin. This may be due to increased resistance to clarithromycin (OR=6.12,95%CI 3.99-9.40, P<0.01).The previous exposure to quinolones (OR=3.65, 95%CI 1.27-10.49, P<0.05) was relevant to the decreased eradication rate of BQT containing levofloxacin, which was probably explained by the increased resistance to levofloxacin (OR=2.50, 95%CI 1.69-3.71, P<0.01). But the previous history of nitroimidazole did not impact the efficacy of BQT containing metronidazole. Conclusions: In patients newly diagnosed with H.pylori infection, the previous exposure to macrolide or quinolones antibiotics is related to lower eradiation rates of H. pylori. Although the exposure to nitroimidazole also indicates drug resistance to metronidazole, the clinical efficacy of BQT with metronidazole 400 mg four times a day is not affected.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Bismuto/uso terapêutico , Claritromicina/uso terapêutico , Quimioterapia Combinada , Infecções por Helicobacter/tratamento farmacológico , Humanos , Inibidores da Bomba de Prótons/uso terapêutico , Estudos Retrospectivos
18.
Molecules ; 26(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684806

RESUMO

Disposal of palm oil mill effluent (POME), which is highly polluting from the palm oil industry, needs to be handled properly to minimize the harmful impact on the surrounding environment. Photocatalytic technology is one of the advanced technologies that can be developed due to its low operating costs, as well as being sustainable, renewable, and environmentally friendly. This paper reports on the photocatalytic degradation of palm oil mill effluent (POME) using a BiVO4 photocatalyst under UV-visible light irradiation. BiVO4 photocatalysts were synthesized via sol-gel method and their physical and chemical properties were characterized using several characterization tools including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), surface area analysis using the BET method, Raman spectroscopy, electron paramagnetic resonance (EPR), and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). The effect of calcination temperature on the properties and photocatalytic performance for POME degradation using BiVO4 photocatalyst was also studied. XRD characterization data show a phase transformation of BiVO4 from tetragonal to monoclinic phase at a temperature of 450 °C (BV-450). The defect site comprising of vanadium vacancy (Vv) was generated through calcination under air and maxima at the BV-450 sample and proposed as the origin of the highest reaction rate constant (k) of photocatalytic POME removal among various calcination temperature treatments with a k value of 1.04 × 10-3 min-1. These findings provide design guidelines to develop efficient BiVO4-based photocatalyst through defect engineering for potential scalable photocatalytic organic pollutant degradation.


Assuntos
Bismuto , Resíduos Industriais/análise , Óleo de Palmeira/isolamento & purificação , Fotólise , Vanadatos , Poluentes Químicos da Água/análise , Bismuto/química , Catálise , Cristalografia por Raios X , Microscopia Eletrônica de Varredura , Análise Espectral Raman , Vanadatos/síntese química , Vanadatos/química , Gerenciamento de Resíduos/métodos
19.
Anal Chem ; 93(38): 12995-13000, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34524810

RESUMO

Herein, a photoelectrochemical (PEC) assay was designed for a highly sensitive DNA determination relying upon the SnO2/BiOBr p-n heterojunction as a photoactive material and SiO2 as a signal quencher. Compared with most traditional heterojunctions, the SnO2/BiOBr p-n heterostructure not only lessened the recombination of the photogenerated electron-hole pairs but also promoted the light-harvesting in the ultraviolet-visible (UV-vis) region, leading to further enhanced photoelectric conversion efficiency and photocurrent, which demonstrated 12.1-fold and 6.4-fold increments versus those of pure SnO2 and BiOBr, respectively. Additionally, the limited quantity of target DNA (a fragment of p53 gene) could be transformed into abundant output DNA-SiO2 by employing the Nt·BstNBI enzyme-assisted signal amplification procedure, leading to a highly improved detection sensitivity of the biosensor. Then, output DNA-SiO2 hybridized with the capture DNA anchored on the modified electrode surface, remarkably diminishing the PEC signal and thus achieving sensitive DNA determination. The elaborated PEC biosensor demonstrated outstanding performance within the linear range between 0.5 fM and 5 nM and a low limit of detection down to 0.18 fM, paving a new way for fabricating heterojunction with exceptional photoactive performance and demonstrating the enormous potential for detecting multitudinous biomarkers in bioanalysis and clinical therapy.


Assuntos
Técnicas Biossensoriais , Dióxido de Silício , Bismuto , DNA , Técnicas Eletroquímicas , Limite de Detecção
20.
Chem Commun (Camb) ; 57(71): 8989-8992, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34486607

RESUMO

We present the in situ formation of a hole-transporting material (bismuth hexacyanoferrate) on the surface of bismuth tungstate aimed at an innovative photoelectrochemical strategy. This approach enabled a competent aptasensing platform for chloramphenicol that was amenable to homogenous, label-free, and split-mode detection.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Bismuto/química , Técnicas Eletroquímicas/métodos , Compostos de Tungstênio/química , Animais , Cloranfenicol/análise , Cloranfenicol/química , Ferricianetos/química , Contaminação de Alimentos/análise , Lagos/análise , Limite de Detecção , Leite/química , Processos Fotoquímicos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
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