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1.
Materials (Basel) ; 17(14)2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39063707

RESUMO

Fabricating efficient oxygen evolution reaction (OER) electrocatalysts is crucial for water electrocatalysis. Herein, the spinel-type high-entropy oxides of (Co, Fe, Mn, Ni, Cr)3O4 were synthesized through the high-temperature calcination approach. The influences of calcination temperatures on structures and electrochemical properties were investigated. The optimized catalyst of HEO-900 contains the hybrid structure of regular polyhedrons and irregular nanoparticles, which is beneficial for the exposure of electrochemically active sites. It was identified that the abundant high-valence metal species of Ni3+, Co3+, Fe3+, Mn4+, and Cr3+ are formed during the OER process, which is generally regarded as the electrochemically active sites for OER. Because of the synergistic effect of multi-metal active sites, the optimized HEO-900 catalyst indicates excellent OER activity, which needs the overpotential of 366 mV to reach the current density of 10 mA cm-2. Moreover, HEO-900 reveals the prominent durability of running for 24 h at the current density of 10 mA cm-2 without clear delay. Therefore, this work supplies a promising route for preparing high-performance multi-metal OER electrocatalysts for water electrocatalysis application.

2.
Environ Pollut ; : 124609, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39074690

RESUMO

Fluorochemical industry is an emerging industry leading to environmental emissions of fluoride ion, fluorinated greenhouse gases (GHGs) and per- and polyfluoroalkyl substances (PFASs) globally. Chlorofluorocarbon (CFCs) and hydrochlorofluorocarbon (HCFCs) are the primary causes of ozone layer depletion, and together with hydrofluorocarbons (HFCs), they contribute to global climate warming. PFAS are emerging persistent organic pollutants, comprising thousands of materials including perfluoroalkyl acids (PFAAs), perfluoroalkane sulfonamides (FASAs), and fluoropolymers.As the implementation of the Montreal Protocol and the Stockholm Convention makes progress, fluorochemical industry is searching for alternatives like HFCs, perfluoroalkyl ether carboxylic acids (PFECAs) and etc.. Even though studies on chemical processes and environmental influences of the fluorochemical industry are plentiful, research on emissions of fluorine chemicals from different fluorochemical industry is still scarce. In this study, we conducted on-site sampling to analyze the distribution of fluorine chemicals in the surrounding environment of the fluorochemical industrial sites. The sampling sites represent different stages of fluorochemical industry production, including fluorite mining, synthesis of fluorochemical raw materials like fluorocarbons, and fine fluorine product processing which is mostly PFAS. Results show that at the fluorite mining stage, concurrent emissions of fluoride ion and CFC-12 contribute to the primary environmental issue. Perfluorooctanoic acid (PFOA) and some short-chain PFASs like perfluorobutanoic acid (PFBA), perfluoropentanoic acid (PFPeA), perfluoroheptanoic acid (PFHpA), and perfluorobutanesulfonic acid (PFBS) are the main pollutants from fluocarbons production, accompanied by emissions of fluorinated GHGs such as HFC-32, and HCFC-22. At the fine fluorine product synthesis stage where produces fluoropolymers, perfluoropolyethers and fluorinated surfactants, PFAS especially for emerging alternatives PFECAs like hexafluoropropylene oxide dimer acid (HFPODA) and Perfluoro-4-oxapentanoic acid (PF4OPeA), as well as fluorinated GHGs like HFC-23 and HFC-227ea, require increasing attention.

3.
Schizophr Res ; 270: 281-288, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38944974

RESUMO

BACKGROUND: The striatum is thought to play a critical role in the pathophysiology and antipsychotic treatment of schizophrenia. Previous studies have revealed abnormal functional connectivity (FC) of the striatum in early-onset schizophrenia (EOS) patients. However, no prior studies have examined post-treatment changes of striatal FC in EOS patients. METHODS: We recruited 49 first-episode drug-naïve EOS patients to have resting-state functional magnetic resonance imaging scans at baseline and after 8 weeks of treatment with antipsychotics, along with baseline scanning of 34 healthy controls (HCs) for comparison purposes. We examined the FC values between each seed in striatal subregion and the rest of the brain. The Positive and Negative Syndrome Scale (PANSS) was applied to measure psychiatric symptoms in patients. RESULTS: Compared with HCs at baseline, EOS patients exhibited weaker FC of striatal subregions with several brain regions of the salience network and default mode network. Meanwhile, FC between the dorsal caudal putamen (DCP) and left supplementary motor area, as well as between the DCP and right postcentral gyrus, was negatively correlated with PANSS negative scores. Furthermore, after 8 weeks of treatment, EOS patients showed decreased FC between subregions of the putamen and the triangular part of inferior frontal gyrus, middle frontal gyrus, supramarginal gyrus and inferior parietal lobule. CONCLUSIONS: Decreased striatal FC is evident, even in the early stages of schizophrenia, and enhance our understanding of the neurodevelopmental abnormalities in schizophrenia. The findings also demonstrate that reduced striatal FC occurs after antipsychotic therapy, indicating that antipsychotic effects need to be accounted for when considering striatal FC abnormalities in schizophrenia.

4.
Microbes Environ ; 39(2)2024.
Artigo em Inglês | MEDLINE | ID: mdl-38763742

RESUMO

Microcystins (MCs) produced by Microcystis aeruginosa are harmful to animal and human health, and there is currently no effective method for their removal. Therefore, the development of biological approaches that inhibit cyanobacteria and remove MCs is needed. We identified strain MB1, confirmed as Morchella, using morphological and mole-cular evolution methods. To assess the impact of strain MB1 on M. aeruginosa, we conducted an experiment in which we inoculated M. aeruginosa with Morchella strain MB1. After their co-cultivation for 4| |d, the inoculation with 0.9696| |g MB1 completely inhibited and removed M. aeruginosa while concurrently removing up to 95% of the MC content. Moreover, within 3| |d of their co-cultivation, MB1 removed more than 50% of nitrogen and phosphorus from the M. aeruginosa solution. Therefore, the development of effective biological techniques for MC removal is paramount in safeguarding both the environment and human well-being. We herein successfully isolated MB1 from its natural habitat. This strain effectively inhibited and removed M. aeruginosa and also reduced the content of nitrogen and phosphorus in the M. aeruginosa solution. Most importantly, it exhibited a robust capability to eliminate MCs. The present results offer a new method and technical reference for mitigating harmful algal blooms.


Assuntos
Proliferação Nociva de Algas , Microcistinas , Microcystis , Nitrogênio , Fósforo , Microcistinas/metabolismo , Microcystis/metabolismo , Microcystis/crescimento & desenvolvimento , Microcystis/química , Fósforo/metabolismo , Nitrogênio/metabolismo
5.
Ecotoxicol Environ Saf ; 272: 116041, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38350213

RESUMO

Although PFOS has been banned as a persistent organic pollutant, it still exists in large quantities within the environment, thus impacting the health of aquatic ecosystems. Previous studies focused solely on high PFOS concentrations, disregarding the connection with environmental factors. To gain a more comprehensive understanding of the PFOS effects on aquatic ecosystems amidst changing environmental conditions, this study investigated the cellular responses of Microcystis aeruginosa to varying PFOS concentrations under heatwave and nutrient stress conditions. The results showed that PFOS concentrations exceeding 5.0 µg/L had obvious effects on multiple physiological responses of M. aeruginosa, resulting in the suppression of algal cell growth and the induction of oxidative damage. However, PFOS concentration at levels below 20.0 µg/L has been found to enhance the growth of algal cells and trigger significant oxidative damage under heatwave conditions. Heatwave conditions could enhance the uptake of PFOS in algal cells, potentially leading to heightened algal growth when PFOS concentration was equal to or less than 5.0 µg/L. Conversely, deficiency or limitation of nitrogen and phosphorus significantly decreased algal abundance and chlorophyll content, inducing severe oxidative stress that could be mitigated by exposure to PFOS. This study holds significance in managing the impact of PFOS on algal growth across diverse environmental conditions.


Assuntos
Microcystis , Ecossistema , Clorofila , Estresse Oxidativo , Fósforo/farmacologia
6.
Opt Lett ; 48(24): 6400-6403, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099758

RESUMO

Laser beam steering is important for classical and quantum information processing. On-chip beam steering is a major motivation for developing large-scale photonic integrated circuits such as optical phased arrays. A major challenge for such arrays is to simultaneously control a large number of on-chip phase shifters, which requires a complicated analog control algorithm and rapidly increasing power consumption. We report a green light (532 nm) 1 × 16 focal plane array photonic integrated circuit with simple control and low power consumption. Fabricated on a silicon nitride platform, the focal plane array achieves angular beam steering over a 10° field of view, with ultra-low electrical power consumption (4 × 3.1 mW).

7.
Molecules ; 28(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37894485

RESUMO

Lowering blood cholesterol levels is crucial for reducing the risk of cardiovascular disease in patients with familial hypercholesterolemia. To develop Perilla frutescens (L.) Britt. leaves as a functional food with a cholesterol-lowering effect, in this study, we collected P. frutescens (L.) Britt. leaves from different regions of China and Republic of Korea. On the basis of the extraction yield (all components; g/kg), we selected P. frutescens (L.) Britt. leaves from Hebei Province, China with an extract yield of 60.9 g/kg. After evaluating different concentrations of ethanol/water solvent for P. frutescens (L.) Britt. leaves, with luteolin 7-glucuronide as the indicator component, we selected a 30% ethanol/water solvent with a high luteolin 7-glucuronide content of 0.548 mg/g in Perilla. frutescens (L.) Britt. leaves. Subsequently, we evaluated the cholesterol-lowering effects of P. frutescens (L.) Britt. leaf extract and luteolin 7-glucuronide by detecting total cholesterol in HepG2 cells. The 30% ethanol extract lowered cholesterol levels significantly by downregulating 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase expression. This suggests that P. frutescens (L.) Britt leaves have significant health benefits and can be explored as a potentially promising food additive for the prevention of hypercholesterolemia-related diseases.


Assuntos
Perilla frutescens , Humanos , Glucuronídeos , Luteolina , Extratos Vegetais/farmacologia , Solventes , Etanol , Colesterol , Água , Folhas de Planta
8.
Int J Biol Macromol ; 247: 125677, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37406916

RESUMO

Dyeing wastewater is a carcinogenic pollutant, which is widely known for its harmful effects on humans and marine organisms. In this study, a novel composite was prepared by blending thiourea modified chitosan with zinc sulfide nanoparticles (T-CS/ZnS) to comprehensively remove methyl orange (MO), rhodamine B (Rh B), and methylene blue (MB) effectively. Characterization results suggested that the synthesized composite has an irregular and rough surface that provided high specific surface area for adsorption process, while the strong optical response and low bandgap width contributed to the subsequent photocatalytic degradation of adsorbed dye molecules. Under optimum experimental conditions, the removal rates of MO, Rh B, and MB were 99.59 %, 99.49 %, and 91.04 %, respectively. Amino and hydroxyl groups provide electrons in photocatalytic reactions. The reaction process is consistent with the quasi-first-order kinetic model, and the material has good stability and regeneration potential. This study indicated that T-CS/ZnS composite is a highly effective material for the treatment of dyeing wastewaters.


Assuntos
Quitosana , Poluentes Químicos da Água , Humanos , Corantes , Águas Residuárias , Sulfetos , Adsorção , Poluentes Químicos da Água/análise , Azul de Metileno
9.
J Colloid Interface Sci ; 650(Pt A): 58-66, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37392500

RESUMO

Liquid crystal (LC) droplets exhibit unique and sensitive response behaviors to surface absorptions, making them promising candidates for sensing aplications. Here, we have developed a label-free, portable, and cost-effective sensor for the specific and rapid detection of silver ions (Ag+) in drinking-water samples. To achieve this, we have modified cytidine into a surfactant (denoted as C10-M-C) and anchored it onto the surface of LC droplets. The specific binding ability between cytidine and Ag+ enables LC droplets anchored with C10-M-C to respond rapidly and specifically to Ag+ ions. Furthermore, the sensitivity of the response meets requirements for the harmless concentration of Ag+ in drinking-water. The sensor we developed is label-free, portable, and cost-effectively. We believe that the sensor reported here can be applied to the detection of Ag+ in drinking-water and environmental samples.

10.
Sci Total Environ ; 890: 164207, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37196964

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are a class of synthetic organic fluorides that have been widely used in various industrial and consumer applications. However, their potential ecological risks have raised concerns. In this study, PFASs were investigated in different environmental media in the Jiulong River and Xiamen Bay regions of China, revealing widespread contamination of PFASs in the watershed. PFBA, PFPeA, PFOA, and PFOS were detected in all 56 sites, with short-chain PFASs dominating (72 % of the total). Novel PFAS alternatives, including F53B, HFPO-DA, and NaDONA, were detected in >90 % of the water samples. Seasonal and spatial variations in PFAS concentrations were observed in the Jiulong River estuary, while Xiamen Bay was not significantly affected by seasonal changes. In sediment, PFSAs were dominant with long-chains while PFCAs with short-chains, and the occurrence was influenced by water depth and salinity. PFSAs were more inclined to be adsorbed in sediments than PFCAs, and log Kd of PFCAs increased with the numbers of -CF2-. Paper packaging, machinery manufacturing, WWTP discharge, airport and dock activities were the dominant sources of PFASs. Risk quotient showed that PFOS or PFOA may pose high toxicity to Danio rerio and Chironomus riparius. Although the overall ecological risk in the catchment is still low, the hazard of bio-concentration under long-term exposure and multi-pollutant synergistic toxicity cannot be ignored.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Animais , Água , Ácidos Alcanossulfônicos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Peixe-Zebra , China , Fluorocarbonos/análise
11.
Anal Methods ; 15(20): 2505-2511, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37183758

RESUMO

Copper plays a key role in the human body; meanwhile, excess Cu2+ ions can result in various diseases. Nanoclusters (NCs) are often used to measure Cu2+ ions, but there are two difficulties. On the one hand, a single probe of NCs is easily affected by environmental factors. On the other hand, it is difficult to mask the interference of Pb2+ ions and Cd2+ ions in the process of detecting Cu2+ ions. As a new type of quantum dots (QDs), tungsten disulfide quantum dots (WS2-QDs) have some advantages of simple synthesis and stable luminescence properties. Stable WS2-QDs with blue fluorescence are used as a reference probe, while gold silver nanoclusters (AuAgNCs) with red fluorescence are used as a response probe. A ratiometric fluorescent sensor was constructed by mixing the two styles of fluorescent probes, which is abbreviated as NCs/QDs. This nano-sensor can be used to detect the concentration of Cu2+ ions, in which the fluorescence of QDs does not change significantly, while the fluorescence of NCs can be quenched by Cu2+ ions. The concentration of Cu2+ ions can be determined as low as 0.12 µM with a linear range from 0.3 to 3 µM. The common interference caused by Pb2+ and Cd2+ ions can be eliminated by the phosphate buffer solution (PBS). This sensor was used to detect the concentration of Cu2+ in river water with satisfactory results.

12.
Foods ; 12(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36981186

RESUMO

In this study, we developed a novel offline high-performance liquid chromatography (HPLC) method based on 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) radicals for antioxidant screening in 20 polyphenolic compounds and used the Trolox equivalent antioxidant capacity assay to evaluate their antioxidant activity. Compared to the existing offline HPLC methods based on 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH), the offline HPLC method based on the AAPH radical is more sensitive. Additionally, we applied this method to Lepechinia meyenii (Walp.) Epling extract and screened out seven antioxidants, caffeic acid, hesperidin, rosmarinic acid, diosmin, methyl rosmarinate, diosmetin, and n-butyl rosmarinate, which are known antioxidants. Therefore, this study provides new insights into the screening of antioxidants in natural extracts.

13.
Food Chem ; 418: 135891, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36965395

RESUMO

Herein, we have introduced hybridization chain reaction (HCR) into the photonic crystals (PhCs) hydrogel, for the first time, realizing HCR for inducing the change of the optical signal of PhCs hydrogel and using this hydrogel as a sensor for determination of the aflatoxin B1 (AFB1). By using specific sequences as the cross-linker, the extension of the cross-linker by HCR drives the swelling of the hydrogel, and the optical property of 2D PhCs array converts this swelling into a change of the Debye diffraction ring. Moreover, by further selecting the aptamer to construct the cross-linker, the hydrogel is also endowed with a unique capability for AFB1, making the hydrogel a novel sensor based on the signal amplification strategy. The results show that the designed hairpin DNAs can effectively trigger the HCR and cause the swelling of hydrogel, and the hydrogel sensor has a good determination performance and high specific recognition for AFB1.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aflatoxina B1/análise , Hidrogéis/química , Aptâmeros de Nucleotídeos/química , DNA/genética , DNA/química , Hibridização de Ácido Nucleico , Técnicas Biossensoriais/métodos , Limite de Detecção
14.
Anal Chem ; 95(8): 4220-4226, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36786428

RESUMO

Bisphenol A (BPA), one of the most abundantly produced endocrine disrupting chemicals, is widely used in everyday plastic products and thus must be monitored. Multimode sensing platforms are able to combine the advantages of different strategies while solving the issues of inaccurate test results of single signal sensing. However, the exploration in this field is limited due to the compromise of sensing conditions and inevitable mutual interferences of different systems. Herein, we constructed a two-dimensional photonic crystal dually cross-linked supramolecular hydrogel (2DPCDCSH) by utilizing a host-guest pair of ß-cyclodextrin (ß-CD) and tert-butyl (t-Bu) as the second cross-linking for colorimetric and fluorescent dual-mode sensing of BPA. Based on the fact that BPA can act as a competitive guest to break the host-guest interaction between ß-CD and t-Bu, the cross-linking density decreased and an expansion-induced structural color change occurred. Sensitive and selective BPA detection can be easily achieved by measuring the Debye diffraction ring diameter or observing the color change of 2DPC with a detection limit of 1 µg mL-1. Moreover, the formation of the ß-CD/BPA complex gave a significant enhancement of the intrinsic fluorescence of BPA, obtaining a detection limit of 0.001 µg mL-1. The two sensing systems can share the same reaction condition and yield a wider dynamic response range than the single signal strategy. Overall, the proposed method presented an efficient, rapid, cost-effective, and regenerative dual-mode method for BPA analysis and shed new insights for the design of diversified sensing platforms.

15.
Exp Neurol ; 359: 114272, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370841

RESUMO

A novel understanding of peripheral nerve injury is epithelial-mesenchymal transition (EMT), which characterizes the process of dedifferentiation and transformation of Schwann cells after nerve injury. Despite being regarded as an important mechanism for healing nerve injuries, long-term EMT is the primary cause of fibrosis in other tissue organs. The potential mechanism promoting neurofibrosis in the process of chronic degeneration of nerve injury and the effects of motor neurons (MNs) transplantation on neurofibrosis and repair of nerve injury were studied by transcriptome sequencing and bioinformatics analysis, which were confirmed by in vivo and in vitro experiments. Even 3 months after nerve injury, the distal nerve maintained high levels of transforming growth factor ß-1 (TGFß-1) and Snail family transcriptional repressor 2 (Snai2). The microenvironment TGFß-1, Snai2 and endogenous TGFß-1 formed a positive feedback loop in vivo and in vitro, which may contribute to the sustained EMT state and neurofibrogenesis in the distal injured nerve. Inhibiting TGFß-1 and Snai2 expression and reversing EMT can be achieved by transferring MNs to distal nerves, and the removal of transplanted MNs is capable of reactivating EMT and promoting the growth of proximal axons. In conclusion, EMT persisting can be an explanation for distal neurofibrosis and a potential therapeutic target. By reversibly regulating EMT, MNs transplantation can alleviate neurofibrogenesis of distal nerve in chronic degeneration.


Assuntos
Transição Epitelial-Mesenquimal , Transdução de Sinais , Células de Schwann/metabolismo , Neurônios Motores/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta/farmacologia
16.
Rev Sci Instrum ; 93(11): 114707, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461418

RESUMO

A compact mesoband radiation system is designed and tested. The system is composed of a charging power supply, a Marx generator, a switched quarter-wavelength oscillator, and a circularly polarized patch antenna. The Marx generator outputs a fast high-voltage pulse with a rise time of 10 ns and an amplitude of 100 kV, which is used to charge the oscillator. The oscillator consists of a quarter-wavelength coaxial transmission line, a ring ground switch, and a coupler. It generates a mesoband oscillation pulse with a center frequency of 350 MHz and a percentage bandwidth of 10%. The oscillation pulse is radiated by the circularly polarized patch antenna. The measured radiation factor is greater than 50 kV, and the radiation waveform is consistent with the simulation waveform.

17.
Huan Jing Ke Xue ; 43(11): 4801-4809, 2022 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-36437053

RESUMO

Emerging pollutants have drawn global concerns under rapid urbanization and industrialization. However, research has been relatively independent on specific groups of pollutants due to the limitation of the discipline. In this study, from the perspective of interdisciplinary research, taking the fluorochemical industry as an example, two major categories of emerging pollutants, per-and polyfluoroalkyl substances (PFAS) and ozone-depleting substances (ODS), were discussed regarding their co-emission. The co-production mechanism of the two types of pollutants were discussed from the production processes to reveal their internal relationship; their differences and cross-processes in the emission routes were analyzed, as well as the technical approaches and challenges required in sample collection, pretreatment, and instrumental analysis. The eco-environmental effects, including ecological and human health risks, ozone depletion, and global warming effects caused by the two types of pollutants in different media were comprehensively summarized. We also further expanded the perspectives of stakeholder analysis, life cycle analysis, and mass balance analysis to provide suggestions for further research and management of emerging pollutant co-emissions.


Assuntos
Poluentes Ambientais , Ozônio , Humanos , Monitoramento Ambiental , Urbanização , Indústrias
18.
RSC Adv ; 12(31): 19875-19884, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35865193

RESUMO

Silicon dioxide (SiO2) has attracted much attention as an ideal coating material for iron (Fe)-based soft magnetic powder cores (SMPCs). However, maintaining the integrity and uniformity of Fe-based/SiO2 core-shell heterostructures is still a challenge. The evolution mechanism of core-shell heterostructures determines the performance of Fe-based SMPCs. Herein, the evolution of the core-shell structures and heterogeneous interfaces of Fe-Si@SiO2 SMPCs with axial pressure and the influence of the evolution on the SMPCs performance were investigated. The results show that in the axial pressure range of 10-15 kN, the core-shell heterostructures were gradually integrated, whereas the SiO2 insulation coatings underwent an amorphous-to-crystalline transformation. At axial pressure above 16 kN, the Fe-Si powder melted partially, and the core-shell heterostructure collapsed due to overheating, caused by the gradient temperature field during the hot-press sintering. When the core-shell heterostructure was intact, the Fe-Si@SiO2 SMPCs showed a permeability of over 38 with a wide and stable frequency range of 100-300 kHz, a saturation magnetisation of 231.7 emu g-1, resistivity of 0.8 mΩ cm and total loss of 704.7 kW m-3 at 10 mT and 100 kHz. When the core-shell heterostructure was destroyed, the resistivity dropped dramatically and the loss increased to 765.0 and 897.4 kW m-3. These results show the relationship between the core-shell heterostructure of Fe-Si@SiO2 SMPCs, axial pressure and magnetic properties, which would be vital in achieving high power density, high efficiency and miniaturisation in SMPCs.

19.
Analyst ; 147(15): 3585-3592, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35822491

RESUMO

There is an increasing need to develop simple yet effective sensors with high sensitivity, high selectivity, rapid response, and low cost for on-site detection of UO22+ in the environment in planned or emergency situations. Herein, we develop a UO22+ responsive interpenetrating porous photonic crystal ball (IPPCB) sensor by template replication and a two-step activation method. The amidoxime group and carboxyl group in the hydrogel drive the shrinkage of the hydrogel network through the coordination with UO22+, which reduces the lattice spacing, thereby changing the structure color and shifting the reflection peak position. Therefore, we can perform a semi-quantitative analysis of UO22+ with the naked eye or a fiber spectrometer. Benefiting from the sensor's spherical symmetry and periodic interpenetrating porous structure, the sensor can provide angle-independent, fast (12 min), and sensitive (minimum detection concentration of 1 nM) detection of UO22+. Moreover, IPPCBs have high selectivity and excellent regeneration performance, which can be applied to real sample detection.


Assuntos
DNA Catalítico , DNA Catalítico/química , Hidrogéis , Íons/química , Fótons , Porosidade
20.
Chem Commun (Camb) ; 58(32): 5009-5012, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35362504

RESUMO

Herein, a signal-on liquid crystal microarray (LCM) sensor is designed for the first time with a micro-spectral optical sensing signal. Depending on the change of the orientation of the LC molecules in the LCM films and the intensity of the spectral peaks of the PhCs, the signal-on LCM biosensor achieves the detection of AFB1 and the Partial Response Mechanism (PSM) of the LCM films is discovered.


Assuntos
Técnicas Biossensoriais , Cristais Líquidos , Aflatoxina B1/análise , Bioensaio , Limite de Detecção , Análise em Microsséries
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