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1.
Small ; 20(27): e2310972, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38282180

RESUMEN

Recently, aqueous zinc-ion batteries with conversion mechanisms have received wide attention in energy storage systems on account of excellent specific capacity, high power density, and energy density. Unfortunately, some characteristics of cathode material, zinc anode, and electrolyte still limit the development of aqueous zinc-ion batteries possessing conversion mechanism. Consequently, this paper provides a detailed summary of the development for numerous aqueous zinc-based batteries: zinc-sulfur (Zn-S) batteries, zinc-selenium (Zn-Se) batteries, zinc-tellurium (Zn-Te) batteries, zinc-iodine (Zn-I2) batteries, and zinc-bromine (Zn-Br2) batteries. Meanwhile, the reaction conversion mechanism of zinc-based batteries with conversion mechanism and the research progress in the investigation of composite cathode, zinc anode materials, and selection of electrolytes are systematically introduced. Finally, this review comprehensively describes the prospects and outlook of aqueous zinc-ion batteries with conversion mechanism, aiming to promote the rapid development of aqueous zinc-based batteries.

2.
Compr Rev Food Sci Food Saf ; 23(4): e13398, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38925595

RESUMEN

Food science encounters increasing complexity and challenges, necessitating more efficient, accurate, and sensitive analytical techniques. Mass spectrometry imaging (MSI) emerges as a revolutionary tool, offering more molecular-level insights. This review delves into MSI's applications and challenges in food science. It introduces MSI principles and instruments such as matrix-assisted laser desorption/ionization, desorption electrospray ionization, secondary ion mass spectrometry, and laser ablation inductively coupled plasma mass spectrometry, highlighting their application in chemical composition analysis, variety identification, authenticity assessment, endogenous substance, exogenous contaminant and residue analysis, quality control, and process monitoring in food processing and food storage. Despite its potential, MSI faces hurdles such as the complexity and cost of instrumentation, complexity in sample preparation, limited analytical capabilities, and lack of standardization of MSI for food samples. While MSI has a wide range of applications in food analysis and can provide more comprehensive and accurate analytical results, challenges persist, demanding further research and solutions. The future development directions include miniaturization of imaging devices, high-resolution and high-speed MSI, multiomics and multimodal data fusion, as well as the application of data analysis and artificial intelligence. These findings and conclusions provide valuable references and insights for the field of food science and offer theoretical and methodological support for further research and practice in food science.


Asunto(s)
Análisis de los Alimentos , Tecnología de Alimentos , Espectrometría de Masas , Tecnología de Alimentos/métodos , Espectrometría de Masas/métodos , Análisis de los Alimentos/métodos
3.
Small ; 19(50): e2304504, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37635108

RESUMEN

Aqueous zinc-ion batteries (AZIBs) are considered to be one of the most promising devices for large-scale energy storage systems owing to their high theoretical capacity, environmental friendliness, and safety. However, the ionic intercalation or surface redox mechanisms in conventional cathode materials generally result in unsatisfactory capacities. Conversion-type aqueous zinc-tellurium (Zn-Te) batteries have recently gained widespread attention owing to their high theoretical specific capacities. However, it remains an enormous challenge to improve the slow kinetics of the aqueous Zn-Te batteries. Here, MoO2 nanoclusters embedded in hierarchical nitrogen-doped carbon nanoflower (MoO2 /NC) hosts are successfully synthesized and loaded with Te in aqueous Zn-Te batteries. Benefitting from the highly dispersed MoO2 nanoclusters and hierarchical nanoflower structure with a large specific surface area, the electrochemical kinetics of the Te redox reaction are significantly improved. As a result, the Te-MoO2 /NC electrode exhibits superior cycling stability and a high specific capacity of 493 mAh g-1 at 0.1 A g-1 . Meanwhile, the conversion mechanism is systematically explored using a variety of ex situ characterization methods. Therefore, this study provides a novel approach for enhancing the kinetics of the Te redox reaction in aqueous Zn-Te batteries.

4.
Opt Express ; 31(10): 16380-16392, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37157717

RESUMEN

The distributed acoustic sensing system can obtain the vibration signal caused by the vibration of the train. By analyzing these wheel-rail vibration signals, an abnormal wheel-rail relationship identification scheme is proposed. The variational mode decomposition is employed for signal decomposition, thereby obtaining intrinsic mode functions with prominent abnormal fluctuations. The kurtosis value of each intrinsic mode function is calculated, which is compared with the threshold value for the identification of trains with abnormal wheel-rail relationship. And the extreme point of the abnormal intrinsic mode function is used to locate the bogie with an abnormal wheel-rail relationship. Experimental demonstration verifies that the proposed scheme can identify the train and locate the bogie with an abnormal wheel-rail relationship.

5.
Microb Pathog ; 183: 106320, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37625663

RESUMEN

BACKGROUND: Transmissible gastroenteritis virus (TGEV), which belongs to the coronaviruses (CoVs), causes diarrhea and high mortality rates in piglets and poses a huge threat and loss to the pig industry in China. METHOD: We estimated the prevalence of TGEV in Chinese pig animals from 1983 to 2022 by screening 36 papers on TGEV investigations in China from databases such as China Knowledge Network (CNKI), Wanfang Database, Science and Technology Journal Repository (VIP), PubMed, and ScienceDirect, excluding duplicate literature and other host studies according to the exclusion criteria we developed, and excluding literature with incomplete data to extract information from studies that could estimate the prevalence of TGEV infection in pigs in mainland China. RESULTS: A total of 36 studies (including data from 50,403 pigs) met our evaluation criteria. The overall estimated prevalence of TGEV infection in pigs in China is 10% (3887/50403), and the prevalence of TGEV in northeast China is 38% (2582/3078700) is significantly higher than the rest of China. The prevalence of TGEV infection was related to the sampling season and region. CONCLUSION: The results of the study show that the prevalence of TGEV is clearly seasonal and regional. Therefore, further research and monitoring of the prevalence of TGEV infection and the development of control programs based on different conditions are essential. In addition, effective and robust regulatory measures should be taken in colder regions to prevent the spread and transmission of TGEV in pigs.


Asunto(s)
Gastroenteritis Porcina Transmisible , Virus de la Gastroenteritis Transmisible , Animales , China/epidemiología , Diarrea , Gastroenteritis/epidemiología , Gastroenteritis/veterinaria , Prevalencia , Porcinos , Gastroenteritis Porcina Transmisible/epidemiología , Gastroenteritis Porcina Transmisible/virología
6.
Microb Pathog ; 184: 106367, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37778704

RESUMEN

Macrophages play a pivotal role in controlling Mycobacterium infection, and the pathogen thrives in the event of immune evasion and immunosuppression of macrophages. Mammalian cell entry proteins (Mce) are required for Mycobacterium tuberculosis (M. tb) growth and the host cell's initial phagocytosis and cytokine response. Mce2D protein is one of a family of proteins that infect M. tb; however, the function and mechanism of action remain unclear. In this study, we constructed the Mce2D knockout strain using Mycobacterium smegmatis to study the function of Mce2D in the infection of macrophages. The results indicated that compared to the knockout strain, the release of proinflammatory cytokines (TNF-α and IL-1ß) reduced when WT strain infected the macrophages. Moreover, Mce2D boosted the metabolism of oxidized fatty acids, increased the energy supply of TCA, and lowered the glycolysis of glucose in macrophages after bacterial infection, all of which prevented the polarization of macrophages to M1, which was driven by the fact that Mce2D blocked ERK2 phosphorylation by interacting with ERK2 through its DEF motif. This, in turn, promoted nuclear translocation of HIF-1α, allowing signal accumulation, which increased the HIF-1α transcription levels. Finally, the mouse infection experiment showed that Mce2D caused blockage of M1 polarization of alveolar macrophages, resulting in reduced bactericidal activity and antigen presentation, weakening Th1 cell-mediated immune response and helping bacteria escape the immune system. Our results reveal that Mce2D causes immune escape by blocking M1 polarization in macrophages, providing potential targets for the rational design of therapies against M. tb infection.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Ratones , Animales , Mycobacterium tuberculosis/metabolismo , Macrófagos/microbiología , Transducción de Señal , Sistema de Señalización de MAP Quinasas , Citocinas/metabolismo , Mamíferos/metabolismo
7.
Opt Express ; 30(10): 17307-17320, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-36221556

RESUMEN

Intrusion identification has been an intractable task for perimeter security. One of the primary challenges is to possess high identification rate over a long-distance range monitoring. This paper proposes an intrusion identification scheme based on ultra-weak fiber Bragg grating (UWFBG) arrays. The scheme is acquired by the combination of a Gaussian mixture model (GMM) and a hidden Markov model (HMM). The time dependencies are obtained by the analysis of relevant sensors in UWFBG arrays from the procedure of intrusions. The features extracted from vibration signals with time dependencies are used as the input of GMM-HMM. The GMM-HMM simultaneously analyzes features and time dependencies to identify intrusion. Experimental demonstration verifies that the proposed scheme can identify three intrusions (walking, knocking and climbing) and two non-intrusions (heavy truck passing and wind blowing) with the average identification rate of 98.2%. By the comparison tests with other six classifiers, the proposed GMM-HMM scheme shows a solid performance in the integrated evaluation for intrusion identification.

8.
Exp Cell Res ; 398(2): 112418, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33309808

RESUMEN

BACKGROUND: NIMA-related kinase-7 (NEK7) is a serine/threonine kinase that drives cell-cycle dynamics by modulating mitotic spindle formation and cytokinesis. It is also a crucial modulator of the pro-inflammatory effects of NOD-like receptor 3 (NLRP3) inflammasome. However, the role of NEK7 in microglia/macrophages post-spinal cord injury (SCI) is not well defined. METHODS: In this study, we performed both in vivo and in vitro experiments. Using an in vivo mouse SCI model, NEK7 siRNAs were administered intraspinally. For in vitro analysis, BV-2 microglia cells with NEK7-siRNA were stimulated with 1 µg/ml lipopolysaccharide (LPS) and 2 mM Adenosine triphosphate (ATP). RESULTS: Here, we found that the mRNA and protein levels of NEK7 and NLRP3 inflammasomes were upregulated in spinal cord tissues of injured mice and BV-2 microglia cells exposed to Lipopolysaccharide (LPS) and Adenosine triphosphate (ATP). Further experiments established that NEK7 and NLRP3 interacted in BV-2 microglia cells, an effect that was eliminated following NEK7 ablation. Moreover, NEK7 ablation suppressed the activation of NLRP3 inflammasomes. Although NEK7 inhibition did not significantly improve motor function post-SCI in mice, it was found to attenuate local inflammatory response and inhibit the activation of NLRP3 inflammasome in microglia/macrophages of the injured spinal cord. CONCLUSION: NEK7 amplifies NLRP3 inflammasome pro-inflammatory signaling in BV-2 microglia cells and mice models of SCI. Therefore, agents targeting the NEK7/NLRP3 signaling offers great promise in the treatment of inflammatory response post-SCI.


Asunto(s)
Inflamasomas/metabolismo , Macrófagos/metabolismo , Microglía/metabolismo , Quinasas Relacionadas con NIMA/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Adenosina Trifosfato/farmacología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , ARN Mensajero/metabolismo , Transducción de Señal/efectos de los fármacos , Traumatismos de la Médula Espinal/cirugía
9.
Sensors (Basel) ; 22(15)2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35957211

RESUMEN

Changes in the geological environment and track wear, and deterioration of train bogies may lead to the looseness of subway fasteners. Identifying loose fasteners randomly distributed along the subway line is of great significance to avoid train derailment. This paper presents a convolutional autoencoder (CAE) network-based method for identifying fastener loosening features from the distributed vibration responses of track beds detected by an ultra-weak fiber Bragg grating sensing array. For an actual subway tunnel monitoring system, a field experiment used to collect the samples of fastener looseness was designed and implemented, where a crowbar was used to loosen or tighten three pairs of fasteners symmetrical on both sides of the track within the common track bed area and the moving load of a rail inspection vehicle was employed to generate 12 groups of distributed vibration signals of the track bed. The original vibration signals obtained from the on-site test were converted into two-dimensional images through the pseudo-Hilbert scan to facilitate the proposed two-stage CAE network with acceptable capabilities in feature extraction and recognition. The performance of the proposed methodology was quantified by accuracy, precision, recall, and F1-score, and displayed intuitively by t-distributed stochastic neighbor embedding (t-SNE). The raster scan and the Hilbert scan were selected to compare with the pseudo-Hilbert scan under a similar CAE network architecture. The identification performance results represented by the four quantification indicators (accuracy, precision, recall, and F1-score) based on the scan strategy in this paper were at least 23.8%, 9.5%, 20.0%, and 21.1% higher than those of the two common scan methods. As well as that, the clustering visualization by t-SNE further verified that the proposed approach had a stronger ability in distinguishing the feature of fastener looseness.


Asunto(s)
Vías Férreas , Tecnología
10.
Electrophoresis ; 42(16): 1552-1559, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34128241

RESUMEN

Oyster is rich in plasmalogens that are ether phospholipids with biological functions to human body. Air-frying is a popular technique for preparing delicious oyster but makes the plasmalogens vulnerable to oxidation. In this study, the effect of air-frying processing on plasmalogens oxidation was studied by lipidomic approach. Plasmalogens were always mixed with normal phospholipids, thus the lipid extract was treated with mild acid hydrolysis to rapidly degrade plasmalogens owing to the acid lability of vinyl ether linkage at sn-1 position. After hydrophilic interaction chromatography MS/MS analysis, there were three plasmalogen classes, plasmanylcholine, plasmanylethanolamine, and plasmanylinositol, completely separated, and each plasmalogen molecular species was identified and quantified. It indicated that the content of plasmalogens underwent an obvious decrease during the air-frying process. To weaken such effect, the influence of air-frying temperature was further inspected by multivariate statistical analyses. The main variables, including the ions of m/z 756.4927, 784.5486, 828.5812, etc., were revealed by unsupervised principle component analysis, supervised orthogonal partial least-square analysis, and variable importance in projection plot. As a conclusion, air-frying has health benefits in reducing fat content but destructive to plasmalogens, thus interventions are recommended to prevent the degradation of plasmalogens.


Asunto(s)
Ostreidae , Animales , Hidrólisis , Lipidómica , Plasmalógenos , Espectrometría de Masas en Tándem
11.
Microb Pathog ; 152: 104618, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33220443

RESUMEN

Over the past decade, various avian influenza viruses have been isolated from wild ducks found in the northeast of China. To monitor the prevalence of multiple subtype specific AIVs antibodies, 1705 wild ducks' eggs from six wetlands of northeast China were analyzed for surveillance of H1, H3, H5, and H7 AIVs antibodies by c-ELISA and HI test from Jan 2017 to Dec 2019. The results show that the combined frequency of multiple subtype specific AIVs antibodies were H1 (12.32%), H3 (8.15%), H5 (2.05%), and H7 (3.46%) respectively. Therefore, a detailed analysis of the geographical distribution of AIVs in China, and the risk factors for human infection is of vital importance. This study provides basic data for other researchers to deeply study AIVs distribution characteristics, and for governments to develop detailed measures to control the spread of AIVs.


Asunto(s)
Virus de la Influenza A , Gripe Aviar , Animales , China/epidemiología , Patos , Yema de Huevo , Humanos , Gripe Aviar/epidemiología , Filogenia
12.
Opt Lett ; 46(17): 4402-4405, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34470026

RESUMEN

A high dynamic range distributed acoustic sensing (DAS) system is demonstrated based on a dual-wavelength (2λ) interferometric acoustic sensor array, constructed using 2λ fiber Bragg grating pairs (FBGPs). Each FBGP is composed of two weak FBGs presenting -30-dB reflectivity and center wavelengths of 1535 nm and 1565 nm. With the phase demodulation results from the two wavelengths, 2λ linear regression phase unwrapping is implemented, which significantly enhances the dynamic range of the DAS system. By examining the four time-division-multiplexed sensors, an average background noise level of -105.2dBrad/Hz at 1 kHz and a cross talk level lower than -70dB at 1 kHz are achieved.

13.
Cancer Cell Int ; 21(1): 4, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33397392

RESUMEN

BACKGROUND: Leptin Receptor (LEPR) has been suggested to have several roles in cancer metastasis. However, the role of LEPR and its underlying mechanisms in lymphatic metastasis of hepatocarcinoma have not yet been studied. METHODS: We performed bioinformatics analysis, qRT-PCR, western blotting, immunohistochemistry, immunofluorescence, enzyme-linked immunosorbent, coimmunoprecipitation assays and a series of functional assays to investigate the roles of LEPR in hepatocellular carcinoma. RESULTS: We discovered that LEPR was highly expressed in liver cancer tissues, and the expression of LEPR in Hca-F cells was higher than that in Hca-P cells. Furthermore, LEPR promotes the proliferation, migration and invasion and inhibits the apoptosis of hepatocarcinoma lymphatic metastatic cells. Further studies indicated that LEPR interacts with ANXA7. Mechanistically, LEPR regulated ERK1/2 and JAK2/STAT3 expression via ANXA7 regulation. CONCLUSIONS: These findings unveiled a previously unappreciated role of LEPR in the regulation of lymphatic metastatic hepatocellular carcinoma, assigning ANXA7-LEPR as a promising therapeutic target for liver cancer treatments.

14.
J Dairy Sci ; 104(3): 3569-3574, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33358821

RESUMEN

Staphylococcus aureus is one of the most common mastitis-causing bacteria in dairy cows. It is associated with reduced production performance in animals and with huge financial losses for the dairy industry worldwide. An accurate and sensitive method for the early diagnosis and identification of Staph. aureus in milk samples is essential. The present study aimed to establish a closed-tube isothermal multiple self-matching-initiated amplification (IMSA) technique for visual confirmation of the presence of Staph. aureus targeting the nuc conserved sequence gene. The specific primers successfully amplified the target sequence within 45 min at 63°C reaction temperature and using the optimal components of the reaction system. The positive amplicon showed bright green fluorescence under UV light when mixed with the chromogenic substrate SYBR Green I, and the negative samples remained orange in color. We observed fluorescence and a ladder-like pattern in the IMSA amplicon for all Staph. aureus strains, and we observed no significant change for the non-Staph. aureus strains. The IMSA assay had high specificity compared with loop-mediated isothermal amplification (LAMP): it confirmed the presence of all 7 Staph. aureus strains, and we found no false-positive results for the 12 non-Staph. aureus strains. The lower limit of detection for the IMSA assay was 1 × 102 cfu/mL, 10-fold more sensitive than the results obtained using LAMP. We also successfully applied the IMSA assay to confirm the presence of Staph. aureus in milk samples of cows with mastitis, and the results were consistent with those of LAMP and real-time PCR. The present study reports the use of IMSA to confirm the presence of Staph. aureus and provides a potentially useful method for rapid preliminary screening for Staph. aureus.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Infecciones Estafilocócicas , Animales , Bovinos , Femenino , Mastitis Bovina/diagnóstico , Leche , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Sensibilidad y Especificidad , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/genética
15.
Angew Chem Int Ed Engl ; 60(45): 24022-24027, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34498366

RESUMEN

We developed a tandem electrocatalyst for CO2 -to-CO conversion comprising the single Cu site co-coordinated with N and S anchored carbon matrix (Cu-S1 N3 ) and atomically dispersed Cu clusters (Cux ), denoted as Cu-S1 N3 /Cux . The as-prepared Cu-S1 N3 /Cux composite presents a 100 % Faradaic efficiency towards CO generation (FECO ) at -0.65 V vs. RHE and high FECO over 90 % from -0.55 to -0.75 V, outperforming the analogues with Cu-N4 (FECO only 54 % at -0.7 V) and Cu-S1 N3 (FECO 70 % at -0.7 V) configurations. The unsymmetrical Cu-S1 N3 atomic interface in the carbon basal plane possesses an optimized binding energy for the key intermediate *COOH compared with Cu-N4 site. At the same time, the adjacent Cux effectively promotes the protonation of *CO2 - by accelerating water dissociation and offering *H to the Cu-S1 N3 active sites. This work provides a tandem strategy for facilitating proton-coupled electron transfer over the atomic-level catalytic sites.

16.
Opt Express ; 28(16): 23189-23197, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32752319

RESUMEN

A high-precision wear measurement method with temperature stability achieved by measuring the length variation of a fiber Bragg grating (FBG) is proposed. The adoption of the optical frequency-domain reflectometry (OFDR) technology makes the spatial resolution of this measurement method reach 15.13 µm, and the offline and online measurement accuracies are 30 µm and 100 µm, respectively. The systematic error of the FBG length measuring system is within 30 µm. Because the length measurement is done with a short FBG instead of a much longer fiber, the measurement error induced by the time-varying temperature or strain is significantly reduced in the proposed method. The spatial resolution and accuracy of this method is suitable for wear measurements of various parts in the mechanical field, such as bearings, gears, and pistons.

17.
Opt Express ; 28(5): 6794-6805, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-32225919

RESUMEN

A scheme is proposed for the identification of surface intrusion events, from signals detected by an ultra-weak fiber Bragg grating array in a subway tunnel. The spectral subtraction and the root mean square of the power spectral density are combined to extract event signals. The local characteristics-scale decomposition and the multi-scale permutation entropy are employed subsequently for feature extraction, which can improve the event recognition rate from the perspective of multi-scale analysis. Experimental demonstration verifies that the proposed scheme can identify four common events. Among the events, the discrete pulse construction and the continuous pulse construction on the ground surface are intrusion events, the subway train traveling in the tunnel and the lorry passing on the ground surface are non-intrusion events. The average recognition rate of 96.57% is achieved, which can satisfy actual application requirements.

18.
Opt Express ; 28(11): 16045-16056, 2020 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-32549436

RESUMEN

Reliable sensing and accurate location of a weak and small hot spot are critical for applications in industrial infrastructure monitoring. We propose and experimentally demonstrate a practical and reliable distributed hot spot detection method using ultra-weak fiber Bragg gratings (UWFBGs) array and optical time-domain reflectometry (OTDR) based interrogator. To reliably detect the hot spots, the grating spacing of the sensor array is decreased to a similar size of the hot spot. All UWFBGs within a fiber section (FS) are considered as one sensing element, and the wavelength-division multiplexing technique is introduced to reduce crosstalk between adjacent FSs. To retrieve the sensing information, the proposed FS spectrum interrogation method based on OTDR technology is numerically analyzed and experimentally demonstrated. The interrogator exploits the reflection spectrum of each FS instead of each grating, enabling the low-speed hardware implementation of the whole demodulation method. Experimental results show that the expected hot spot can be successfully detected with a sensing resolution of 10 cm and a location resolution of 1 m over a range of 2 km by exploiting 10-ns pulsewidth. Besides, the temperature measurement can be demonstrated with a temperature sensing precision of ± 1°C and a measurement time of 1.5 s, which are meaningful for the early warning of centimeters-sized fire source in some oil and gas pipelines monitoring applications.

19.
Electrophoresis ; 41(5-6): 379-385, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32040861

RESUMEN

Justicia procumbens is a food and medicine homologous variety, popularly used for making vegetable soups. In this study, a novel mesoporous silica was synthesized and used as the sorbent of SPE for the purification of lignans from J. procumbens. A laboratory-made SPE cartridge was packed with 100 mg of mesoporous silica, which was washed with 10% methanol and eluted using 0.8 mL acetonitrile after sample loading. Afterward, the extract was analyzed by ultra-performance liquid chromatography (UPLC) and MS/MS. All the lignans were efficiently separated in 6 min with the noise level in the range of 50-150 cps. 6'-Hydroxy justicidin B, 6'-hydroxy justicidin A, justicidin B, chinensinaphthol methyl ether, justicidin C, and neojusticdin A were identified to be the dominant molecular species in J. procumbens with contents of 0.065-0.37 mg/g in three tested sample batches from different geographic origins. In conclusion, the proposed mesoporous silica based SPE UPLC-MS/MS method is efficient in linearity (R2 = 0.9989-0.9996), sensitivity (LOD ≤0.13 µg/kg and LOQ ≤0.42 µg/kg), precision (RSDintra-day ≤3.12 and RSDinter-day ≤4.56), and recovery (83.42-96.11%, RSD ≤2.88%).


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Género Justicia/química , Lignanos/análisis , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Modelos Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Dióxido de Silicio/química
20.
Opt Lett ; 45(16): 4523-4526, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32796999

RESUMEN

Acoustic impedance sensing based on forward stimulated Brillouin scattering (FSBS) in fiber has attracted the attention of researchers in recent years. Here, we propose a novel, to the best of our knowledge, multipoint sensing scheme based on FSBS, which explores frequency-division multiplexing. Since the resonance center frequencies of the FSBS-invoked acoustic modes are dependent on the fiber diameter, different fiber sections can be differentiated using carefully selected representative peaks in the FSBS spectrum. With a Sagnac loop structure, continuous-wave light is adopted for FSBS excitation, reducing the required fiber length for efficient opto-acoustic interaction. By evaluating the linewidths of representative peaks, simultaneous acoustic impedance sensing at multiple locations is realized with 0.8 m sensor size.

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