Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 96
Filtrar
1.
Light Sci Appl ; 13(1): 153, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965220

RESUMO

Photodetection has attracted significant attention for information transmission. While the implementation relies primarily on the photonic detectors, they are predominantly constrained by the intrinsic bandgap of active materials. On the other hand, photothermoelectric (PTE) detectors have garnered substantial research interest for their promising capabilities in broadband detection, owing to the self-driven photovoltages induced by the temperature differences. To get higher performances, it is crucial to localize light and heat energies for efficient conversion. However, there is limited research on the energy conversion in PTE detectors at micro/nano scale. In this study, we have achieved a two-order-of-magnitude enhancement in photovoltage responsivity in the self-rolled tubular tellurium (Te) photodetector with PTE effect. Under illumination, the tubular device demonstrates a maximum photovoltage responsivity of 252.13 V W-1 and a large detectivity of 1.48 × 1011 Jones. We disclose the mechanism of the PTE conversion in the tubular structure with the assistance of theoretical simulation. In addition, the device exhibits excellent performances in wide-angle and polarization-dependent detection. This work presents an approach to remarkably improve the performance of photodetector by concentrating light and corresponding heat generated, and the proposed self-rolled devices thus hold remarkable promises for next-generation on-chip photodetection.

2.
Micromachines (Basel) ; 15(4)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38675236

RESUMO

In this work, we propose a SiC-NSFET structure that uses a PTS scheme only under the gate, with SiC layers under the source and drain, to improve the leakage current and thermal reliability. Punch-through stopper (PTS) doping is widely used to suppress the leakage current, but aggressively high PTS doping will cause additional band-to-band (BTBT) current. Therefore, the bottom oxide isolation nanosheet field-effect transistor (BOX-NSFET) can further reduce the leakage current and become an alternative to conventional structures with PTS. However, thermal reliability issues, like bias temperature instability (BTI), hot carrier injection (HCI), and time-dependent dielectric breakdown (TDDB), induced by the self-heating effect (SHE) of BOX-NSFET, become more profound due to the lower thermal conductivity of SiO2 than silicon. Moreover, the bottom oxide will reduce the stress along the channel due to the challenges associated with growing high-quality SiGe material on SiO2. Therefore, this method faces difficulties in enhancing the mobility of p-type devices. The comprehensive TCAD simulation results show that SiC-NSFET significantly suppresses the substrate leakage current compared to the conventional structure with PTS. In addition, compared to the BOX-NSFET, the stress reduction caused by the bottom oxide is avoided, and the SHE is mitigated. This work provides significant design guidelines for leakage and thermal reliability optimization of next-generation advanced nodes.

3.
Micromachines (Basel) ; 15(3)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38542667

RESUMO

In this paper, we investigate the effects of negative bias instability (NBTI) and self-heating effect (SHE) on threshold voltage in NSFETs. To explore accurately the interaction between SHE and NBTI, we established an NBTI simulation framework based on trap microdynamics and considered the influence of the self-heating effect. The results show that NBTI weakens the SHE effect, while SHE exacerbates the NBTI effect. Since the width of the nanosheet in NSFET has a significant control effect on the electric field distribution, we also studied the effect of the width of the nanosheet on the NBTI and self-heating effect. The results show that increasing the width of the nanosheet will reduce the NBTI effect but will enhance the SHE effect. In addition, we extended our research to the SRAM cell circuit, and the results show that the NBTI effect will reduce the static noise margin (SNM) of the SRAM cell, and the NBTI effect affected by self-heating will make the SNM decrease more significantly. In addition, our research results also indicate that increasing the nanosheet width can help slow down the NBTI effect and the negative impact of NBTI on SRAM performance affected by the self-heating effect.

4.
Clin Exp Med ; 24(1): 33, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329593

RESUMO

Therapy-related myelodysplastic syndrome (t-MDS) is defined as a complication in patients with cancer following exposure to chemotherapy and/or radiotherapy and has an inferior outcome compared with de novo myelodysplastic syndrome (de novo MDS). This study aimed to estimate and compare the clinical outcomes of haploidentical stem cell transplantation (haplo-HSCT) for t-MDS and de novo MDS. We retrospectively analyzed 96 patients with MDS who received haplo-HSCT between January 2015 and December 2021. Eleven patients with t-MDS and 85 patients with de novo MDS were matched using the case-pair method in a 1:8 ratio with the following pairing criteria: (1) sex, (2) age (± 5 years), (3) year of haplo-HSCT (± 2 years), and (4) blast cell counts (≥ 5% or not). The 3-year overall survival and disease-free survival after haplo-HSCT for t-MDS versus de novo MDS patients were 72.7% versus 75.1% (P = 0.99) and 54.5% versus 67.0% (P = 0.50), respectively. The 3-year cumulative incidence of relapse was 36.4% versus 15.5% (P = 0.08), respectively. In multivariate analysis, there was no difference in relapse between t-MDS and de novo MDS. The 3-year cumulative non-relapse mortality rates were 9.1% versus 17.6% (P = 0.45), respectively. This study confirmed the comparable clinical outcomes of haplo-HSCT on the prognosis of t-MDS and de novo MDS.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas , Segunda Neoplasia Primária , Humanos , Estudos Retrospectivos , Síndromes Mielodisplásicas/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Recidiva
5.
Stat Appl Genet Mol Biol ; 23(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363177

RESUMO

Developments in biotechnologies enable multi-platform data collection for functional genomic units apart from the gene. Profiling of non-coding microRNAs (miRNAs) is a valuable tool for understanding the molecular profile of the cell, both for canonical functions and malignant behavior due to complex diseases. We propose a graphical mixed-effects statistical model incorporating miRNA-gene target relationships. We implement an integrative pathway analysis that leverages measurements of miRNA activity for joint analysis with multimodal observations of gene activity including gene expression, methylation, and copy number variation. We apply our analysis to a breast cancer dataset, and consider differential activity in signaling pathways across breast tumor subtypes. We offer discussion of specific signaling pathways and the effect of miRNA integration, as well as publish an interactive data visualization to give public access to the results of our analysis.


Assuntos
Neoplasias da Mama , MicroRNAs , Humanos , Feminino , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias da Mama/metabolismo , Variações do Número de Cópias de DNA , Perfilação da Expressão Gênica , Metilação de DNA/genética , Expressão Gênica , Regulação Neoplásica da Expressão Gênica
6.
Nano Lett ; 24(5): 1594-1601, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38134416

RESUMO

Blue quantum dot (QD) light-emitting diodes (QLEDs) exhibit unsatisfactory operational stability and electroluminescence (EL) properties due to severe nonradiative recombination induced by large numbers of dangling bond defects and charge imbalance in QD. Herein, dipolar aromatic amine-functionalized molecules with different molecular polarities are employed to regulate charge transport and passivate interfacial defects between QD and the electron transfer layer (ETL). The results show that the stronger the molecular polarity, especially with the -CF3 groups possessing a strong electron-withdrawing capacity, the more effective the defect passivation of S and Zn dangling bonds at the QD surface. Moreover, the dipole interlayer can effectively reduce electron injection into QD at high current density, enhancing charge balance and mitigating Joule heat. Finally, blue QLEDs exhibit a peak external quantum efficiency (EQE) of 21.02% with an operational lifetime (T50 at 100 cd m-2) exceeding 4000 h.

7.
Mar Environ Res ; 194: 106329, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159408

RESUMO

The coastal salt marsh wetland is mainly located in the tidal area where sea and land are intertwined, which has the functions of promoting silt and consolidating beach, wave reduction and disaster reduction, and is an ecological barrier against erosion in the coastal zone, which has important ecological value. Nevertheless, owing to the intricate nature of wetland species formation mechanisms and community distribution patterns, the impact of coastal squeeze on Suaeda salsa wetlands loss may not exhibit a linear relationship, necessitating further elucidation of the specific processes involved. Precisely understanding the extent to which coastal squeeze affects the threshold of loss in the Suaeda salsa wetland holds immense importance in safeguarding the distinctive red beach landscape. Furthermore, it represents a pivotal scientific challenge that necessitates resolution in the management of coastal wetlands for their protection and restoration. Hence, drawing upon the theoretical framework concerning the impact of coastal squeeze on the degradation of coastal Suaeda salsa wetland, this study employs the representative silty coastal region of China's northern Liaodong Bay as a case study to conduct empirical investigation. The research integrates Landsat imagery and digital elevation data, and incorporates spatial autocorrelation, elastic coefficient analysis, and barycenter model analysis to examine the threshold of degradation and spatial variations of Suaeda salsa wetland in response to coastal squeeze. The results show that: (1) The risk intensity of coastal squeeze in the study area exhibited a pattern of initial decline followed by an increase from 1995 to 2020, with the highest risk areas predominantly located in the development zone on the eastern bank of the Liao River Estuary. (2) There was a positive correlation between the growth of the coastal squeeze index and the loss of the Suaeda salsa wetland. When the proportion of area in which the coastal squeeze deteriorates reached 43.9%, the Suaeda salsa wetland lose resilience against the impact of coastal squeeze, leading to an intensified rate of loss. (3) Compared with the west side of the Liao River, the critical area of coastal squeeze and the loss barycenter of the Suaeda salsa wetland on the east side of the Liao River have a greater range of changes. The planning and management of coastal ecological restoration necessitates considering the occurrence conditions of the coastal squeeze impact threshold on the loss threshold of wetland and the migration characteristics of the wetland loss area. This approach enables the timely control of coastal squeeze risk intensity in the area and the preservation of wetlands' resistance to external disturbances. Consequently, it holds immense importance for the sustainable development of coastal wetlands.


Assuntos
Chenopodiaceae , Áreas Alagadas , Estuários , Rios , Análise Espacial , China
8.
Sci Adv ; 9(42): eadi7805, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37851806

RESUMO

Uncooled infrared detection based on vanadium dioxide (VO2) radiometer is highly demanded in temperature monitoring and security protection. The key to its breakthrough is to fabricate bolometer arrays with great absorbance and excellent thermal insulation using a straightforward procedure. Here, we show a tubular bolometer by one-step rolling VO2 nanomembranes with enhanced infrared detection. The tubular geometry enhances the thermal insulation, light absorption, and temperature sensitivity of freestanding VO2 nanomembranes. This tubular VO2 bolometer exhibits a detectivity of ~2 × 108 cm Hz1/2 W-1 in the ultrabroad infrared spectrum, a response time of ~2.0 ms, and a calculated noise-equivalent temperature difference of 64.5 mK. Furthermore, our device presents a workable structural paradigm for polarization-sensitive and omnidirectional light coupling bolometers. The demonstrated overall characteristics suggest that tubular bolometers have the potential to narrow performance and cost gap between photon detectors and thermal detectors with low cost and broad applications.

9.
Cardiovasc Diagn Ther ; 13(3): 509-522, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37405013

RESUMO

Background: Mitophagy is an essential factor in mitochondrial quality control and myocardial ischaemia/reperfusion (I/R) injury protection. Because adenosine A2B receptor (A2BR) activation exerts a major role in reducing myocardial I/R injury, the effects of adenosine A2BR activation on cardiac mitophagy under reperfusion conditions were investigated. Methods: 110 adult Wistar rats (7-10 w), weighing 250-350 grams, were cultured in specific-pathogen-free (SPF) conditions before experiments. All hearts were removed and reperfused by Langendorff device. Six hearts with coronary flow (CF) values >28 or <10 mL/min were excluded. Others were arbitrarily divided into the following groups: sham operation group, I/R group, BAY60-6583 (BAY) (1-1,000 nM) + I/R group, PP2 + BAY + I/R group. After ischemia in rats, reperfusion was performed. H9c2 cells were placed in an imitated ischemic environment followed by Tyrode's solution to stimulate hypoxia/reoxygenation (H/R) injury. The mitochondrial fluorescence indicator MitoTracker Green and lysosomal fluorescence indicator LysoTracker Red were used to examine mitochondria and lysosomes, respectively. Colocalization of mitochondrial and autophagy marker proteins was determined by immunofluorescence. Autophagic flow currents were tested by Ad-mCherry-GFP-LC3B. Protein-protein interactions were predicted using a database and analyzed by co-immunoprecipitation. Autophagy marker protein, mitophagy marker protein, and mitophagy protein FUNDC1 were detected by immunoblotting. Results: Compared with those in the I/R group, myocardial autophagy and mitophagy were suppressed by the selective adenosine A2BR agonist BAY, and this effect was inhibited by the selective Src tyrosine kinase inhibitor PP2, indicating that adenosine A2BR activation could inhibit myocardial autophagy and mitophagy by activating Src tyrosine kinase. In support, in H9c2 cells, the selective Src tyrosine kinase inhibitor PP2 inhibited the effect of BAY on TOM20 with LC3 or mitochondria with lysosomes colocalization and autophagy flow. Here, we showed that mitochondrial FUNDC1 co-precipitated with Src tyrosine kinase after BAY was added. Consistently, the immunofluorescence and western blotting results demonstrated that compared to that in the H/R group, the expression of mitochondrial FUNDC1 was reduced by BAY, but this effect was reversed by PP2. Conclusions: Adenosine A2BR activation may inhibit myocardial mitophagy by downregulating expression of the mitochondrial FUNDC1 by activating Src tyrosine kinase under I/R conditions and could increase the interaction between Src tyrosine kinase and FUNDC1.

10.
Sci Rep ; 13(1): 5568, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019907

RESUMO

Based on the counted power system emission factors of North China Power Grid, a community carbon emissions sample database is constructed. The support vector regression (SVR) model is trained to forecast the power carbon emissions, which is optimized by genetic algorithm (GA). A community carbon emission warning system is designed according the results. The dynamic emission coefficient curve of the power system is obtained by fitting the annual carbon emission coefficients. The time series SVR carbon emission prediction model is constructed, while the GA is improved to optimize its parameters. Taking Beijing Caochang Community as an example, a carbon emission sample database is generated based on the electricity consumption and emission coefficient curve to train and test the SVR model. The results show that the GA-SVR model fits well with the training set and the testing set, and the prediction accuracy of the testing set reaches 86%. In view of the training model in this paper, the carbon emission trend of community electricity consumption in the next month is predicted. The carbon emission warning system of the community is designed, and the specific strategy of community carbon emission reduction is proposed.

11.
Eur J Med Chem ; 254: 115371, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37084597

RESUMO

The NaV1.8 channel is a genetically validated target for pain and it is mostly expressed in the peripheral nervous system. Based on the disclosed structures of NaV1.8-selective inhibitors, we designed and synthesized a series of compounds by introducing bicyclic aromatic fragments based on the nicotinamide scaffold. In this research, a systematic structure-activity relationship study was carried out. While compound 2c possessed moderate inhibitory activity (IC50 = 50.18 ± 0.04 nM) in HEK293 cells stably expressing human NaV1.8 channels, it showed potent inhibitory activity in DRG neurons and isoform selectivity (>200-fold against human NaV1.1, NaV1.5 and NaV1.7 channels). Moreover, the analgesic potency of compound 2c was identified in a post-surgical mouse model. These data demonstrate that compound 2c can be further evaluated as a non-addictive analgesic agent with reduced cardiac liabilities.


Assuntos
Canal de Sódio Disparado por Voltagem NAV1.7 , Niacinamida , Humanos , Camundongos , Animais , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Células HEK293 , Dor/tratamento farmacológico , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Analgésicos/química
12.
Int J Mol Sci ; 24(6)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36982900

RESUMO

Chlorophyll drives plant photosynthesis. Under stress conditions, leaf chlorophyll content changes dramatically, which could provide insight into plant photosynthesis and drought resistance. Compared to traditional methods of evaluating chlorophyll content, hyperspectral imaging is more efficient and accurate and benefits from being a nondestructive technique. However, the relationships between chlorophyll content and hyperspectral characteristics of wheat leaves with wide genetic diversity and different treatments have rarely been reported. In this study, using 335 wheat varieties, we analyzed the hyperspectral characteristics of flag leaves and the relationships thereof with SPAD values at the grain-filling stage under control and drought stress. The hyperspectral information of wheat flag leaves significantly differed between control and drought stress conditions in the 550-700 nm region. Hyperspectral reflectance at 549 nm (r = -0.64) and the first derivative at 735 nm (r = 0.68) exhibited the strongest correlations with SPAD values. Hyperspectral reflectance at 536, 596, and 674 nm, and the first derivatives bands at 756 and 778 nm, were useful for estimating SPAD values. The combination of spectrum and image characteristics (L*, a*, and b*) can improve the estimation accuracy of SPAD values (optimal performance of RFR, relative error, 7.35%; root mean square error, 4.439; R2, 0.61). The models established in this study are efficient for evaluating chlorophyll content and provide insight into photosynthesis and drought resistance. This study can provide a reference for high-throughput phenotypic analysis and genetic breeding of wheat and other crops.


Assuntos
Clorofila , Imageamento Hiperespectral , Triticum/genética , Secas , Melhoramento Vegetal , Folhas de Planta
13.
Dev Psychol ; 59(5): 874-885, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36972094

RESUMO

We examined the development of numerical magnitude representations of fractions and decimals from fourth to 12th grade. In Experiment 1, we assessed the rational number magnitude knowledge of 200 Chinese fourth, fifth, sixth, eighth, and 12th graders (92 girls and 108 boys) by presenting fraction and decimal magnitude comparison tasks as well as fraction and decimal 0-1 and 0-5 number line estimation tasks. Magnitude representations of decimals became accurate earlier, improved more rapidly, and reached a higher asymptotic accuracy than magnitude representations of fractions. Analyses of individual differences revealed positive relations between the accuracy of decimal and fraction magnitude representations at all ages. In Experiment 2, we presented an additional set of 24 fourth graders (14 girls and 10 boys) with the same tasks but with the decimals that were being compared varying in the number of decimal digits. The decimal advantage continued to be present for both magnitude comparison and estimation tasks, indicating that the greater accuracy with decimals was not limited to decimals with equal numbers of decimal digits, though unequal numbers of decimal digits did impact performance with decimals on both magnitude comparison and number line estimation tasks. Implications for understanding numerical development and education are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Povo Asiático , Matemática , Feminino , Humanos , Masculino , Criança , Adolescente
14.
J Environ Manage ; 324: 116255, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36352707

RESUMO

Simulation-based optimization (S-O) frameworks are effective in developing cost-effective watershed management strategies, where optimization algorithms have substantial effect on the quality of strategies. Despite the development and improvement of multi-objective evolutionary algorithms (MOEAs) provide more robust alternatives for optimization, they typically have limited applications in real-world decision contexts. In this study, three advanced MOEAs, including NSGA-II, MOEA/D and NSGA-III, were introduced into the S-O framework and applied to a real-world watershed management problem, and their performance and characteristics were quantified through performance metrics. Results show that a higher crossover or mutation probability do not necessarily promote convergence and diversity of solutions, while a larger generation and population size is helpful for MOEAs to find high-quality solutions. Compared to the other two MOEAs, NSGA-II consistently exhibits robust performance in finding solutions with good convergence and high diversity, and provides more options at the same computational cost, while the degenerate Pareto front of the proposed watershed management problem may account for the poor performance of MOEA/D and NSGA-III in terms of diversity. For a 10% TN or TP reduction target, the average cost of the NSGA-II optimized strategies is 32.22% or 47.83% of the commonly used strategies. In addition, this study also discussed the development of resilient watershed management to buffer the impacts of climate change on aquatic system, the incorporation of fuzzy programming into the S-O framework to develop robust watershed management strategies under uncertainty, and the application of machine learning-based surrogate models to reduce computational cost of the S-O framework. These results can contribute to the understanding of MOEAs and provide useful guidance to decision makers.


Assuntos
Algoritmos , Mudança Climática , Recursos Hídricos , Simulação por Computador , Incerteza
15.
Light Sci Appl ; 11(1): 329, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36414615

RESUMO

The solar X-ray and Extreme Ultraviolet Imager (X-EUVI), developed by the Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences (CIOMP), is the first space-based solar X-ray and Extreme ultraviolet (EUV) imager of China loaded on the Fengyun-3E (FY-3E) satellite supported by the China Meteorological Administration (CMA) for solar observation. Since started work on July 11, 2021, X-EUVI has obtained many solar images. The instrument employs an innovative dual-band design to monitor a much larger temperature range on the Sun, which covers 0.6-8.0 nm in the X-ray region with six channels and 19.5 nm in the EUV region. X-EUVI has a field of view of 42', an angular resolution of 2.5″ per pixel in the EUV band and an angular resolution of 4.1″ per pixel in the X-ray band. The instrument also includes an X-ray and EUV irradiance sensor (X-EUVS) with the same bands as its imaging optics, which measures the solar irradiance and regularly calibrates the solar images. The radiometric calibration of X-EUVS on the ground has been completed, with a calibration accuracy of 12%. X-EUVI is loaded on the FY-3E satellite and rotates relative to the Sun at a uniform rate. Flat-field calibration is conducted by utilizing successive rotation solar images. The agreement between preliminarily processed X-EUVI images and SDO/AIA and Hinode/XRT images indicates that X-EUVI and the data processing algorithm operate properly and that the data from X-EUVI can be applied to the space weather forecast system of CMA and scientific investigations on solar activity.

16.
Research (Wash D C) ; 2022: 9842752, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928304

RESUMO

Practical implementation of minimally invasive biomedical applications has been a long-sought goal for microrobots. In this field, most previous studies only demonstrate microrobots with locomotion ability or performing a single task, unable to be functionalized effectively. Here, we propose a biocompatible shape memory alloy helical microrobot with regulative structure transformation, making it possible to adjust its motion behavior and mechanical properties precisely. Especially, towards vascular occlusion problem, these microrobots reveal a fundamental solution strategy in the mechanical capability using shape memory effect. Such shape-transformable microrobots can not only manipulate thrust and torque by structure to enhance the unclogging efficiency as a microdriller but also utilize the high work energy to apply the expandable helical tail as a self-propulsive stent. The strategy takes advantage of untethered manipulation to operate microsurgery without unnecessary damage. This study opens a route to functionalize microrobots via accurate tuning in structures, motions, and mechanical properties.

17.
Anal Methods ; 14(35): 3451-3457, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36000503

RESUMO

In this paper, a nucleic acid dye-enhanced electrochemical biosensor based on a screen-printed carbon electrode (SPCE) modified with Au nanoparticles (AuNPs) was designed for the detection of Hg2+ in water. AuNPs were modified on the surface of the disposable SPCE through the electrodeposition of HAuCl4. Subsequently, thiolated DNA probes were immobilized on the AuNP-modified electrode surface by Au-S reaction. After Hg2+ was bound with a DNA probe by thymine (T)-Hg2+-thymine (T) mismatch, the DNA probe was folded into a hairpin structure where positively charged GelRed molecules were embedded into the double-stranded part of the hairpin. Thus, the current of [Fe(CN)6]3-/4- increased significantly on account of the decreased electrostatic repulsion at the electrode surface. Under the optimized experimental conditions, the peak current of [Fe(CN)6]3-/4- exhibited a good linear relationship with lgCHg2+ in the concentration of Hg2+ linear range of 0.1 nM to 500 nM, and the limit of detection (S/N = 3) was calculated as 0.04 nM. The electrochemical sensor also exhibited excellent selectivity for Hg2+ in the presence of nine interfering ions, including Na+, Fe3+, Ni2+, Mg2+, Co2+, Pb2+, K+, Al3+ and Cu2+. Meanwhile, the developed electrochemical sensor was tested in the analysis of Hg2+ in tap water and river water samples, and the recoveries ranged from 81.0 to 114%. Therefore, this nucleic acid dye-enhanced electrochemical biosensor provided the advantages of simplicity, sensitivity, and specificity and is expected to be an alternative for Hg2+ detection in actual environmental samples.


Assuntos
Técnicas Biossensoriais , Mercúrio , Nanopartículas Metálicas , Ácidos Nucleicos , Carbono , Sondas de DNA/análise , Sondas de DNA/química , Técnicas Eletroquímicas , Eletrodos , Ouro/química , Íons , Chumbo , Mercúrio/análise , Mercúrio/química , Nanopartículas Metálicas/química , Timina/química , Água/análise
18.
ACS Appl Mater Interfaces ; 14(27): 31277-31284, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35771521

RESUMO

Passive radiative cooling is a spontaneous pattern of reflecting sunlight and radiating heat into the cold outer space through transparent atmosphere windows. In this work, an ordered-porous-array polymethyl methacrylate (OPA-PMMA) film with the properties of excellent radiative cooling is designed and studied. An ultra-high emissivity of 98.4% in the mid-infrared region (3-25 µm) and a good solar reflectance of 85% in the ultraviolet and near-infrared solar spectra (0.2-2.5 µm) were achieved. The surface temperature of the OPA-PMMA film is 16 °C lower than that of the smooth-surface PMMA films and is 8.6 °C lower than that of the commercial white paint in the outdoor test. The structure of the OPA plays an important role in improving solar reflectivity and emissivity. The films are fabricated using a one-step low-cost process that can be applied for large-scale production. It is vital for promoting radiative cooling as a viable energy technology for buildings, fabric, or equipment that need a cooling environment.

19.
Q J Exp Psychol (Hove) ; 75(12): 2382-2396, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35018842

RESUMO

Rational numbers, like fractions, decimals, and percentages, differ in the concepts they prefer to express and the entities they prefer to describe as previously reported in display-rational number notation matching tasks and in math word problem compiling contexts. On one hand, fractions and percentages are preferentially used to express a relation between two magnitudes, while decimals are preferentially used to represent a magnitude. On the other hand, fractions and decimals tend to be used to describe discrete and continuous entities, respectively. However, it remains unclear whether these reported distinctions can extend to more general linguistic contexts. It also remains unclear which factor, the concept to be expressed (magnitudes vs. relations between magnitudes) or the entity to be described (countable vs. continuous), is more predictive of people's preferences for rational number notations. To explore these issues, two corpus studies and a number notation preference experiment were administered. The news and conversation corpus studies detected the general pattern of conceptual distinctions across rational number notations as observed in previous studies; the number notation preference experiment found that the concept to be expressed was more predictive of people's preferences for number notations than the entity to be described. These findings indicate that people's biased uses of rational numbers are constrained by multiple factors, especially by the type of concepts to be expressed, and more importantly, these biases are not specific to mathematical settings but are generalizable to broader linguistic contexts.


Assuntos
Idioma , Linguística , Humanos , Matemática , Comunicação , Extremidade Superior
20.
Sci Total Environ ; 820: 153190, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35051471

RESUMO

Nanoplastics have attracted wide attention worldwide as a new potentially threatening pollutant, and they can cause harm to the organisms and pose threat to the water environment. Therefore, efficient removal techniques for nanoplastics are urgently needed. In this study, CuNi carbon material (CuNi@C) was prepared by hydrothermal method for the removal of polystyrene (PS) nanoplastics from water. CuNi@C was effectively adsorbed on PS nanoplastics. When the CuNi@C dosage increased from 0.1 g/L to 0.3 g/L, the removal efficiency of PS nanoplastics (10 mg/L) elevated from 32.72% to 99.18%. The images of the scanning electron microscope (SEM) and the Fourier transform infrared spectroscopy (FTIR) spectra of CuNi@C confirmed the adsorption of PS nanoplastics on the CuNi@C. The fitting results of adsorption kinetic models and isotherms equations demonstrated that physical adsorption and monolayer coverage were the predominant mechanisms of the PS nanoplastics adsorption on CuNi@C. Thermodynamics analysis illustrated the adsorption of PS nanoplastics on CuNi@C was a spontaneous and endothermic process. The electrostatic attraction occurred in adsorption progress, and the removal efficiency of PS nanoplastics in the acidic system was generally higher than that in the alkaline system. CuNi@C can be recycled via washing and drying treatment and these CuNi@C comparable PS nanoplastics removal performance to the original ones. After four times cycles, CuNi@C can still remove ~75% of total PS nanoplastics from water. This study reveals that CuNi@C can be used as promising techniques for the removal of PS nanoplastics from the aqueous environment.


Assuntos
Poliestirenos , Poluentes Químicos da Água , Adsorção , Carbono , Concentração de Íons de Hidrogênio , Cinética , Microplásticos , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Água , Poluentes Químicos da Água/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...