Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 144
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Angew Chem Int Ed Engl ; 63(17): e202401602, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38345598

RESUMO

Electrochemical biomass conversion holds promise to upcycle carbon sources and produce valuable products while reducing greenhouse gas emissions. To this end, deep insight into the interfacial mechanism is essential for the rational design of an efficient electrocatalytic route, which is still an area of active research and development. Herein, we report the reduction of dihydroxyacetone (DHA)-the simplest monosaccharide derived from glycerol feedstock-to acetol, the vital chemical intermediate in industries, with faradaic efficiency of 85±5 % on a polycrystalline Cu electrode. DHA reduction follows preceding dehydration by coordination with the carbonyl and hydroxyl groups and the subsequent hydrogenation. The electrokinetic profile indicates that the rate-determining step (RDS) includes a proton-coupled electron transfer (PCET) to the dehydrated intermediate, revealed by coverage-dependent Tafel slope and isotopic labeling experiments. An approximate zero-order dependence of H+ suggests that water acts as the proton donor for the interfacial PCET process. Leveraging these insights, we formulate microkinetic models to illustrate its origin that Eley-Rideal (E-R) dominates over Langmuir-Hinshelwood (L-H) in governing Cu-mediated DHA reduction, offering rational guidance that increasing the concentration of the adsorbed reactant alone would be sufficient to promote the activity in designing practical catalysts.

2.
Kidney360 ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38323855

RESUMO

BACKGROUND: OPTIMIZE was a randomized, open-label study evaluating different tenapanor initiation methods. OPTIMIZE evaluated tenapanor alone and in combination with phosphate binders (PBs) to achieve target serum phosphate (P) ≤5.5 mg/dL. METHODS: Patients with inadequately controlled P receiving maintenance dialysis from 42 US locations who were taking PBs with baseline P >5.5 mg/dL and ≤10.0 mg/dL, or were PB-naive with baseline P >4.5 mg/dL and ≤10.0 mg/dL, were included in OPTIMIZE. Participants taking PBs at baseline were randomized to switch from PBs to tenapanor (Straight Switch; n = 151) or reduce PB dosage by ≥50% and add tenapanor (Binder Reduction; n = 152); PB-naive patients started tenapanor alone (Binder-Naive; n = 30). Participants received tenapanor 30 mg twice a day for 10 weeks (part A), followed by an elective, 16-week open-label extension (part B). Outcomes included changes from baseline in P, intact fibroblast growth factor 23 (iFGF23), parathyroid hormone (PTH), serum calcium, and medication burden; patient-reported outcomes; and safety. RESULTS: By part A endpoint, 34.4% (Straight Switch), 38.2% (Binder Reduction), and 63.3% (Binder-Naive) of patients achieved P ≤5.5 mg/dL. Mean P reduction and median pill burden reduction from baseline to part A endpoint were 0.91± 1.7 mg/dL and 4 pills/day for the Straight Switch and 0.99± 1.8 mg/dL and 1 pill/day for the Binder Reduction group. The mean P reduction for Binder-Naive patients was 0.87± 1.5 mg/dL. Among Straight Switch and Binder Reduction patients who completed patient experience questionnaires, 205 of 243 (84.4%) reported an improved phosphate-management routine. Diarrhea was the most common adverse event (133 of 333 [39.9%]). CONCLUSIONS: Tenapanor as monotherapy or in combination with PBs effectively lowered P toward the target range in patients who were PB naïve or who were not at goal despite PB use. FUNDING: Ardelyx, Inc. TRIAL REGISTRATION: NCT04549597.

3.
JMIR Form Res ; 8: e53216, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329787

RESUMO

BACKGROUND: The accumulation of vast electronic medical records (EMRs) through medical informatization creates significant research value, particularly in obstetrics. Diagnostic standardization across different health care institutions and regions is vital for medical data analysis. Large language models (LLMs) have been extensively used for various medical tasks. Prompt engineering is key to use LLMs effectively. OBJECTIVE: This study aims to evaluate and compare the performance of LLMs with various prompt engineering techniques on the task of standardizing obstetric diagnostic terminology using real-world obstetric data. METHODS: The paper describes a 4-step approach used for mapping diagnoses in electronic medical records to the International Classification of Diseases, 10th revision, observation domain. First, similarity measures were used for mapping the diagnoses. Second, candidate mapping terms were collected based on similarity scores above a threshold, to be used as the training data set. For generating optimal mapping terms, we used two LLMs (ChatGLM2 and Qwen-14B-Chat [QWEN]) for zero-shot learning in step 3. Finally, a performance comparison was conducted by using 3 pretrained bidirectional encoder representations from transformers (BERTs), including BERT, whole word masking BERT, and momentum contrastive learning with BERT (MC-BERT), for unsupervised optimal mapping term generation in the fourth step. RESULTS: LLMs and BERT demonstrated comparable performance at their respective optimal levels. LLMs showed clear advantages in terms of performance and efficiency in unsupervised settings. Interestingly, the performance of the LLMs varied significantly across different prompt engineering setups. For instance, when applying the self-consistency approach in QWEN, the F1-score improved by 5%, with precision increasing by 7.9%, outperforming the zero-shot method. Likewise, ChatGLM2 delivered similar rates of accurately generated responses. During the analysis, the BERT series served as a comparative model with comparable results. Among the 3 models, MC-BERT demonstrated the highest level of performance. However, the differences among the versions of BERT in this study were relatively insignificant. CONCLUSIONS: After applying LLMs to standardize diagnoses and designing 4 different prompts, we compared the results to those generated by the BERT model. Our findings indicate that QWEN prompts largely outperformed the other prompts, with precision comparable to that of the BERT model. These results demonstrate the potential of unsupervised approaches in improving the efficiency of aligning diagnostic terms in daily research and uncovering hidden information values in patient data.

4.
Nanoscale ; 16(8): 3838-3880, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38329288

RESUMO

Lead halide perovskites (LHPs) are emerging semiconductor materials for light-emitting diodes (LEDs) owing to their unique structure and superior optoelectronic properties. However, defects that initiate degradation of LHPs through external stimuli and prompt internal ion migration at the interfaces remain a significant challenge. The electric field (EF), which is a fundamental driving force in LED operation, complicates the role of these defects in the physical and chemical properties of LHPs. A deeper understanding of EF-induced defect behavior is crucial for optimizing the LED performance. In this review, the origins and characterization of defects are explored, indicating the influence of EF-induced defect dynamics on LED performance and stability. A comprehensive overview of recent defect passivation approaches for LHP bulk films and nanocrystals (NCs) is also provided. Given the ubiquity of EF, a summary of the EF-induced defect behavior can enhance the performance of perovskite LEDs and related optoelectronic devices.

5.
Am J Gastroenterol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38294158

RESUMO

INTRODUCTION: This post hoc analysis evaluated the efficacy of tenapanor on abdominal symptoms in patients with irritable bowel syndrome with constipation. Abdominal symptoms assessed included pain, discomfort, bloating, cramping, and fullness. METHODS: The abdominal symptom data were pooled from 3 randomized controlled trials (NCT01923428, T3MPO-1 [NCT02621892], and T3MPO-2 [NCT02686138]). Weekly scores were calculated for each abdominal symptom, and the Abdominal Score (AS) was derived as the average of weekly scores for abdominal pain, discomfort, and bloating. The overall change from baseline during the 12 weeks was assessed for each symptom weekly score and the AS. The AS 6/12-week and 9/12-week response rates (AS improvement of ≥2 points for ≥6/12- or ≥9/12-week) were also evaluated. The association of weekly AS response status (reduction of ≥30%) with weekly complete spontaneous bowel movement (CSBM) status (=0 and >0) was assessed. RESULTS: Among 1,372 patients (684 tenapanor [50 mg twice a day] and 688 placebo), the least squares mean change from baseline in AS was -2.66 for tenapanor vs -2.09 for placebo ( P < 0.0001). The 6/12-week AS response rate was 44.4% for tenapanor vs 32.4% for placebo ( P < 0.0001), and for 9/12-week AS, 30.6% for tenapanor vs 20.5% for placebo ( P < 0.0001). A significant association between weekly CSBM status and weekly AS response status was observed each week ( P < 0.0001), with a greater proportion achieving an AS reduction in patients with >0 CSBMs in a week. DISCUSSION: Tenapanor significantly reduced abdominal symptoms in patients with irritable bowel syndrome with constipation, particularly pain, discomfort, and bloating measured by AS, compared with placebo.

6.
Neurogastroenterol Motil ; 35(11): e14658, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37668173

RESUMO

BACKGROUND: Tenapanor, a first-in-class, minimally systemic inhibitor of intestinal sodium/hydrogen exchanger isoform 3 (NHE3), is approved for the treatment of irritable bowel syndrome with constipation (IBS-C) in adults based on two randomized, placebo-controlled, phase III studies (T3MPO-1 [NCT02621892], T3MPO-2 [NCT02686138]). The open-label T3MPO-3 extension study (NCT02727751) enrolled patients who completed these studies to investigate long-term safety and tolerability of tenapanor. METHODS: Patients who completed T3MPO-1 (16 weeks) or T3MPO-2 (26 weeks) were eligible for enrollment in T3MPO-3. Patients in T3MPO-3 received open-label tenapanor 50 mg twice a day for up to an additional 39 (T3MPO-1) or 26 (T3MPO-2) weeks. Treatment-emergent adverse events (TEAEs) were evaluated in the entire T3MPO-3 safety population and in patients who received a total of ≥52 weeks of tenapanor. KEY RESULTS: A total of 312 patients were enrolled in T3MPO-3; 90 received ≥52 weeks of tenapanor. TEAEs were reported in 117 (37.5%) patients in the safety population and in 52 (57.8%) patients who received ≥52 weeks of tenapanor. Diarrhea was the most common TEAE, occurring in 10.6% of the safety population and in 11.1% of patients who received ≥52 weeks of tenapanor. Most cases were mild or moderate in severity, with only two severe cases reported in the safety population. No deaths occurred during the T3MPO-3 study. CONCLUSIONS: Tenapanor was tolerable over ≥52 weeks of treatment and showed similar safety to that seen in shorter studies. Combined results of the T3MPO studies indicate that tenapanor is a valuable new treatment option for patients with IBS-C.


Assuntos
Síndrome do Intestino Irritável , Adulto , Humanos , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/induzido quimicamente , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/tratamento farmacológico , Isoquinolinas/efeitos adversos , Sulfonamidas/efeitos adversos , Trocador 3 de Sódio-Hidrogênio
7.
ACS Appl Mater Interfaces ; 15(36): 42706-42716, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37646254

RESUMO

Quasi-two-dimensional (quasi-2D) perovskites exhibit excellent performance when applied to light-emitting diodes (LEDs). However, quasi-2D perovskite films generally have nonuniform n phases and irregular internal crystal structures, which degrade the device's performance. Here, we propose using a Dion-Jacobson (DJ)-type organic spacer to modulate the phase distribution of the Ruddlesden-Popper (RP) quasi-2D perovskite. A DJ-type organic spacer cation, 1.6-hexamethylenediamine (HDABr2), was introduced into the perovskite as the second spacer cation with propylamine hydrobromide (PABr). As DJ-type and RP-type perovskites have similar spacings, RP-DJ style does not cause a chaotic crystalline structure; instead, it modulates the perovskite crystallization and narrows the phase distribution. In parallel, there is a substantial improvement in the maximum luminance, current efficiency, external quantum efficiency, and device stability of the quasi-2D perovskite LEDs. This work provides a novel concept for combining the organic spacer cations for quasi-2D perovskites.

8.
J Phys Chem Lett ; 14(24): 5481-5488, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37290033

RESUMO

It is still quite challenging to achieve high-performance and stable blue perovskite materials due to their instability and degradation. The lattice strain provides an important pathway to investigate the degradation process. In this article, the lattice strain in perovskite nanocrystals was regulated by the ratio of Cs+, EA+, and Rb+ cations with different sizes. Their electrical structure, formation energy, and ion migration activation energy were calculated with the density functional theory (DFT) method. The luminescence properties and stability of blue lead bromide perovskite nanocrystals were analyzed with spectra regulation from 516 to 472 nm. It was demonstrated that the lattice strain plays an important role in the luminescence performance and degradation process of perovskite materials. The study provides the positive correlation between lattice strain and degradation as well as luminescence properties in lead halide perovskite materials, which is of great importance in uncovering their degradation mechanism and developing stable and high-performance blue perovskite materials.

9.
Nat Commun ; 14(1): 488, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717582

RESUMO

Induced pluripotent stem cell (iPSC) reprogramming is inefficient and understanding the molecular mechanisms underlying this inefficiency holds the key to successfully control cellular identity. Here, we report 24 reprogramming roadblock genes identified by CRISPR/Cas9-mediated genome-wide knockout (KO) screening. Of these, depletion of the predicted KRAB zinc finger protein (KRAB-ZFP) Zfp266 strongly and consistently enhances murine iPSC generation in several reprogramming settings, emerging as the most robust roadblock. We show that ZFP266 binds Short Interspersed Nuclear Elements (SINEs) adjacent to binding sites of pioneering factors, OCT4 (POU5F1), SOX2, and KLF4, and impedes chromatin opening. Replacing the KRAB co-suppressor with co-activator domains converts ZFP266 from an inhibitor to a potent facilitator of iPSC reprogramming. We propose that the SINE-KRAB-ZFP interaction is a critical regulator of chromatin accessibility at regulatory elements required for efficient cellular identity changes. In addition, this work serves as a resource to further illuminate molecular mechanisms hindering reprogramming.


Assuntos
Células-Tronco Pluripotentes Induzidas , Dedos de Zinco , Animais , Camundongos , Reprogramação Celular/genética , Cromatina/genética , Cromatina/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 4 Semelhante a Kruppel
10.
J Phys Chem Lett ; 13(45): 10649-10655, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36354201

RESUMO

Quantum dot (QD) light-emitting devices operating in non-carrier-injection (NCI) mode have attracted intense interest. Revealing the source of carriers that support the periodic electroluminescence is important because there is no injection of carriers from the external electrode. Electrons/holes generated by well-to-well multiple ionization in adjacent QDs are generally recognized as the carrier source for electroluminescence, and the stacked QD layers are necessary. In this work, NCI electroluminescence (NCI-EL) from monolayer QDs is successfully demonstrated, which cannot be properly explained by the previously proposed mechanism of multiple ionization. A working mechanism related to periodic in-well ionization is proposed, in which electrons tunnel directly from the valence band of QDs to the conduction band to form free electrons and holes. The effects of driving voltage amplitude, frequency, and QD size on the NCI-EL performance are investigated. Finite element simulation is used to clarify the ionization process. We believe this work can extend the working mechanism model of NCI-EL from QDs and provide guidance for promoting QD-based light-emitting device performance.

11.
Nanoscale Adv ; 4(6): 1632-1638, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36134380

RESUMO

Quasi-2D perovskites with the general formula of L2A n-1Pb n X3n+1 (L = organic spacer cation, A = small organic cation or inorganic cation, X = halide ion, and n ≤ 5) are an emerging kind of luminescent material. Their emission color can be easily tuned by their composition and n value. Accurate prediction of the photon energy before experiments is essential but unpractical based on present studies. Herein, we use machine learning (ML) to explore the quantitative relationship between the photon energies of quasi-2D perovskite materials and their precursor compositions. The random forest (RF) model presents high accuracy in prediction with a root mean square error (RMSE) of ∼0.05 eV on a test set. By feature importance analysis, the composition of the A-site cation is found to be a critical factor affecting the photon energy. Moreover, it is also found that the phase impurity greatly lowers the photon energy and needs to be minimized. Furthermore, the RF model predicts the compositions of quasi-2D perovskites with high photon energies for blue emission. These results highlight the advantage of machine learning in predicting the properties of quasi-2D perovskites before experiments and also providing color tuning directions for experiments.

12.
iScience ; 25(7): 104531, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35784795

RESUMO

Improving solar energy collection in aquatic environments would allow for superior environmental monitoring and remote sensing, but the identification of optimal photovoltaic technologies for such applications is challenging as evaluation requires either field deployment or access to large water tanks. Here, we present a simple bench-top characterization technique that does not require direct access to water and therefore circumvents the need for field testing during initial trials of development. Employing LEDs to simulate underwater solar spectra at various depths, we compare Si and CdTe solar cells, two commercially available technologies, with GaInP cells, a technology with a wide bandgap close to ideal for underwater solar harvesting. We use this method to show that while Si cells outperform both CdTe and GaInP cells under terrestrial AM1.5G solar irradiance, CdTe and GaInP cells outperform Si cells at depths >2 m, with GaInP cells operating with underwater efficiencies approaching 54%.

13.
RSC Adv ; 12(5): 3081-3089, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35425286

RESUMO

Quasi-2D perovskites are potential materials for optoelectronics like light-emitting diodes (LEDs); compared to their 3D counterparts, they are considered more stable against the atmosphere and more efficient in exciton confining. However, the simultaneous formation of different phases in the quasi-2D perovskite film, i.e., the phase impurity issue, lowers the device performance. We propose using a small molecule additive, trimethylolpropane trimethacrylate (TMPTA), to suppress the phase impurity by mixing it into the antisolvent. The phase pure quasi-2D perovskite film was obtained, and meanwhile, the film quality was also improved. Moreover, the ester functional groups in TMPTA also passivate the charged defects in the perovskite film, minimizing the carrier recombination in the device. Correspondingly, with TMPTA modification, the maximum current efficiency is increased by 25%, and the half lifetime of the PeLEDs is prolonged by three times.

14.
ACS Omega ; 7(9): 7893-7900, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35284748

RESUMO

Thermally activated delayed fluorescence (TADF) materials enable organic light-emitting devices (OLEDs) to exhibit high external quantum efficiency (EQE), as they can fully utilize singlets and triplets. Despite the high theoretical limit in EQE of TADF OLEDs, the reported values of EQE in the literature vary a lot. Hence, it is critical to quantify the effects of the factors on device EQE based on data-driven approaches. Herein, we use machine learning (ML) algorithms to map the relationship between the material/device structural factors and the EQE. We established the dataset from a variety of experimental reports. Four algorithms are employed, among which the neural network performs best in predicting the EQE. The root-mean-square errors are 1.96 and 3.39% for the training and test sets. Based on the correlation and the feature importance studies, key factors governing the device EQE are screened out. These results provide essential guidance for material screening and experimental device optimization of TADF OLEDs.

15.
Phys Chem Chem Phys ; 24(10): 6208-6214, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35229093

RESUMO

All-inorganic perovskites, like CsPbBr3, have gained particular concern due to their excellent material stability. However, aside from the general defect issue in perovskite materials, all-inorganic perovskites also suffer from poor film quality, leading to low device efficiency, especially of perovskite light-emitting diodes (PeLEDs) employing a thin perovskite film as the emission layer. Herein, 1,4-phenyldimethylammonium dibromide (phDMADBr), which has ammonium cations (NH3+) on both terminals, is introduced as the additive in the precursor solution. It is proved that phDMADBr can improve the film coverage; meanwhile, it also presents a more intense passivation effect on point defects than a similar additive with a single NH3+ terminal. As demonstrated by density functional theory (DFT) calculations, phDMADBr tends to anchor onto the Br-dangling bond with both NH3+ tails and enhances the adhesion to the perovskite grain surface. The exposed hydrophobic aryl also protects the perovskite from detrimental environmental factors. Correspondingly, the maximum luminance (Lmax), current efficiency (CE), and device stability of the PeLEDs are enhanced. This work offers special guidance for screening passivation additives for inorganic perovskites.

16.
J Phys Chem Lett ; 13(6): 1506-1511, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35132854

RESUMO

The stable cross-shaped CsPbI3 nanoplates (NPs) with red emission were achieved by chemical synthesis with the assistance of YCl3. Y3+ replacing Pb2+ results in the anisotropic growth of the CsPbI3 nanocrystal to form NPs. Four corners of the NPs dissolved, thus forming the cross-shaped NPs. The emission of NPs was shifted from near-infrared (690 nm) to red emission (640 nm) as the dopant amount of Y3+ increased. Y3+ widens the width of the bandgap, which is also proved by first-principles calculations. In addition, the Cl- passivated the surface defects of the NPs, suppressing the nonradiative recombination. The NPs showed remarkable high photoluminescence quantum yields (PLQY) of 96%. PLQY is even more than 60% when NPs have been stored in a glovebox for more than 90 days. The NPs with adjustable wavelength and enhanced stability have a huge application potential in the field of a high-definition display.

17.
Polymers (Basel) ; 14(3)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35160611

RESUMO

The mitigation of interfacial charge accumulation in solution-processed organic light-emitting diodes (s-OLEDs) is an effective method to improve device performance. In this study, the polar solvent vapor annealing (PSVA) method was used to treat two layers in s-OLED, PEDOT:PSS and mCP:DMAC-DPS emitting layers, separately, to optimize the carrier transmission and balance. After the double-layer PSVA treatment, the current efficiency increased, the lifetime of the device is improved, the efficiency roll-off alleviated from 33.3% to 26.6%, and the maximum brightness increased by 31.3%. It is worth mentioning that the work function of the EML interface reduced by 0.36 eV, and the initial injection voltage of the electrons also reduced. Simulating the solubility of the LUMO and HOMO molecule parts of the mCP and DMAC-DPS, it was found that the LUMO parts had stronger polarity and higher solubility in polar solution than the HOMO parts. By comparing the untreated luminescent layer films, it was found that the PSVA treatment improved the uniformity of the film morphology. We may infer that a more ordered molecular arrangement enhances carrier transport as the LUMO parts tend to be close to the surface and the reduced local state traps on the EML surface promote electron injection. According to the experimental results, the injection of holes and electrons is enhanced from both sides of the EML, respectively, and the charge accumulated at the interface of s-OLEDs is significantly reduced due to the improvement of carrier-transported characteristics.

18.
ACS Appl Mater Interfaces ; 13(51): 61818-61826, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34919371

RESUMO

Near-infrared photodetectors (NIR-PDs) are widely used in communications, biomedical imaging, and national defense. Here we report a new strategy to prepare a short wavelength light filter based NIR-PDs by introducing an interface layer between the perovskite layer and the polymer layer to achieve the selective passage of carriers. Through the synergistic effect of the perovskite and the interface layer, the short wavelength light component in the signal spectrum is effectively filtered out. The organic polymer layer with a bulk heterojunction structure is applied to realize the absorption and conversion of near-infrared light. The prepared device achieves a maximum external quantum efficiency of 83.7% without bias, a high specific detectivity of 1.52 × 1013 Jones, an NIR responsivity of 0.577A/W, and a short response time of 1.73/0.97 µs within the detection range from 770 to 900 nm. All these properties show great advantages compared with other perovskite/polymer hybrid NIR photodetectors that have been reported. This innovative strategy provides a new way to prepare high-performance near-infrared photodetectors.

19.
Polymers (Basel) ; 13(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34372001

RESUMO

Although reported ternary polymer solar cells have higher power conversion efficiency than binary polymers, the mechanism of exciton separation and charge transport in this complex ternary system is still unclear. Herein, based on PM6:Y6:ITIC-M ternary solar cells, we combine the technique of luminescence spectroscopy, including electroluminescence (EL) and photoluminescence (PL) with photovoltaic measurements, to understand clearly the detailed roles of ITIC-M as the third component in the contribution of device performance. The results show that ITIC-M can form the alloy-like composite with Y6 but leave individual Y6 acceptor to conduct charge transfer with PM6 donor, which improves Voc but decreases Jsc because of poor charge transfer capacity of ITIC-M. Meanwhile, the energy transfer from PM6 to ITIC-M exists in the active layers; small IE suppresses exciton dissociation. Deteriorating performance of solar cells demonstrates that, except for complementary absorption spectrum and suitable energy levels in PM6:Y6:ITIC-M system, the synergetic effects of carrier dynamics among different organic materials play an important role in influencing the performance of ternary solar cells.

20.
ACS Appl Mater Interfaces ; 13(23): 26782-26789, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34077176

RESUMO

Technologies for rapid screening of multiple foodborne pathogens have been urgently needed because of the complex food matrix and high outbreaks of foodborne diseases. In this study, multicolor coding up-conversion nanoparticles (UCNPs) were synthesized and applied for rapid and simultaneous detection of five kinds of foodborne pathogens. The multicolor coding UCNPs were obtained through doping different concentrations of a sensitizer (Yb3+) on the shell of the synthesized NaYF4:Yb3+, Tm3+ (20%/2%)@NaYF4:Yb3+, and Er3+ (x %/2%) core/shell nanocrystals. All the UCNPs could emit red and green luminescence simultaneously once excited with near-infrared wavelength (980 nm), and the ratio of red and green (R/G ratio) emission light intensity of each kind of UCNPs varied depending on the Yb3+ doping concentration. In addition, the magnetic nanoparticles (MNPs) modified with the monoclonal antibodies (mAbs) against the target bacteria were used to capture and separate the bacteria, resulting in obtaining the MNP-bacterium complexes. Different UCNPs with multicolor coding acted as signal probes were also modified with the mAbs to react with the MNP-bacterium complexes to form the MNP-bacterium-UCNP sandwich complexes. After the sandwich complexes were excited with a wavelength of 980 nm, the obtained R/G ratios and the green photoluminescence intensity (PL intensity) could be used to distinguish and quantitatively detect foodborne pathogens, respectively. This proposed nanoplatform could detect five foodborne pathogens simultaneously within 2 h with good sensitivity and specificity, showing great potential for multiplex detection of other targets in the fields of medical diagnosis and food security.


Assuntos
Anticorpos Monoclonais/imunologia , Bactérias/patogenicidade , Doenças Transmitidas por Alimentos/diagnóstico , Luminescência , Nanopartículas de Magnetita/química , Bactérias/classificação , Bactérias/imunologia , Doenças Transmitidas por Alimentos/microbiologia , Medições Luminescentes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...