CONCURRENCY AND COMPUTATION-PRACTICE & EXPERIENCE
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2014
·Vol. 27
·期 13
·3184-3204
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IF 0.784
Mihai Alexandru,Thierry Monteil,Petr Lorenz,Fabio Coccetti,Hervé Aubert
Summary This paper deals with the parallel computing and computation time prediction applied to computational electromagnetics based on rigorous methods for large and complex structures, such as tunnels and airplane cabins. The main objective of this work is represented by the electromagnetic computation of an airplane cabin in order to characterize the propagation channel for a given frequency inside the structure. A well-known three-dimensional numerical method, transmission-line matrix, is adopted for this work. Transmission-line matrix modelling method is applied to volumes, using the symmetrical condensed node. The planar structures are modelled with the mode matching approach. In order to analyse the electromagnetic field at high frequencies inside large structures as an airplane cabin, the transmission-line matrix mesh step is very small compared with the size of the physical structure. Thus, the total amount of data that need to be processed exceeds the RAM memory presented on a traditional computing machine. The implementation of the parallel transmission-line matrix algorithm is a viable solution to this problem taking full advantage of the parallel and distributed architectures, as clusters, grids and supercomputers. The results prove the benefits of the grid computing and supercomputer environments to solve electrically large structures. The parallel hybrid approach, based on Message Passing Interface, is designed for Single Programme Multiple Data programming model. The study highlights the role of parallelization scheme, grid versus supercomputer, with respect to the size of the problem and its repartition. In order to access the computing resources available on different parallel computing platforms, users need to respect a charter containing time and resource number restrictions when doing reservations. So, a time prediction model based on the profile of the transmission-line matrix algorithm has been developed to allow safe reservations of the computing nodes on grid environment. To have a good agreement between the measured and the predicted values for the computation time, the problem of the cache misses appearing during the simulation has been considered in the profile-based prediction model of the transmission-line matrix/modal hybrid application, according to the processor cache memory size. The maximum error for the estimated values of the computation times is about 6.09%. The relevance of this work is based on the fact that is given a complete tool to deal with the large electromagnetic structures: a parallel transmission-line matrix implementation to take the advantage of the distributed architectures and a time prediction model in order to optimize the resource reservation and the simulation execution on the computing nodes. Copyright © 2014 John Wiley & Sons, Ltd.
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高影响因子
Molecular Catalysis
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2022
·
IF 5.089
Ying Zhang,Zhi-Wen Duan,Han-Yu Liu,Feng Qian,Pu Wang
Microbial whole-cell catalysis has been a popular method for chiral alcohols preparation. In this study, Cyberlindnera saturnus ZJPH1807 was successfully employed as a biocatalyst to reduce 2-chloro-1-(2,4-dichlorophenyl)ethanone (CPE) to ( R )-2-chloro-1-(2,4-dichlorophenyl)ethanol (( R )-CPEO), a key chiral intermediate of antifungal drug miconazole. In order to further improve the bioprocess yield, natural deep eutectic solvent and cyclodextrin were introduced into the reaction system as additives. It was found that carnitine/trehalose (C/Tre, 1:1 mol/mol) could increase the permeability of cell membrane appropriately and improve the mass transfer rate. And the addition of methyl-β-cyclodextrin (MCD) could improve the solubility of CPE in buffer solution, simultaneously promoting cofactor recycling. Furthermore, MCD and C/Tre exerted a synergistic effect on the acceleration of CPE bioreduction, producing 91.0% yield in 1.5 h at 35.8 mM CPE in a C/Tre-MCD-containing system, with a 12.4-fold increase in productivity compared to neat buffer solution only. When the substrate loading was increased to 67.1 mM, the yield could also achieve 84.2%. The established bioreduction process was also feasible at 100 mL preparation scale with a 88.5% ( R )-CPEO yield. The integration of C/Tre and MCD can significantly improve catalytic efficiency for hydrophobic substrates and be applied in biocatalysis.
研究领域:
生物化学
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微生物学
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制药工程
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高影响因子
International Journal of Electrochemical Science
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2023
·
IF 1.5
Yuyuan Liu,Jie Liu,Qianli Zhang,Jie Wei,Guiyun Xu
Bismuth (Bi) nano-needle, nano-rod, nano-sheet, and nano-flower were synthesized using a facile one- step solvothermal method by adjusting the volume of ethylenediamine (EDA). The prepared Bi nanoparticles were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis and their formation mechanism was discussed. Bi nano-particle modified carbon paste electrode (CPE) combined with differential pulse anodic stripping voltammetry (DPASV) was developed for the determination of Cd (II). It was shown that Bi nano-flower modified electrode displayed the highest detection sensitivity on account of its particular three-dimensional structures. The stripping peak currents of Cd (II) at “bulk” and “drop coating” Bi nano-flower modified CPEs were compared with those of Bi film modified CPEs using “in-situ” and “out-situ” plating methods. The optimized detection conditions were 5% Bi nano-flower bulk modified CPE at pH 4.4, deposition potential of -1.2 V ( vs . AgCl/Ag) and deposition time of 200 s. The linear range, sensitivity and detection limit were 0.05 - 1 μM, 27.5 μA/μM, and 2.4 nM , respectively. The proposed Bi nano-flower bulk modified CPE was conveniently usable in the trace Cd (II) analysis for environmental water samples with the recovery rang of 91.1%-105.6%.
研究领域:
分析化学
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环境科学
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高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2017
·
IF 5.401
Zhenping Liu,Mingliang Jin,Jieping Cao,Juan Wang,Xin Wang,Guofu Zhou,Albert van den Berg,Lingling Shui
In this work, a high-sensitive electrochemical sensor of Norfloxacin (NFX) has been developed using a composite electrode of MWCNT-CPE/pRGO-ANSA/Au. MWCNT-CPE is the multi-walled carbon nanotubes (MWCNT) – carbon paste electrode (CPE). pRGO-ANSA means the partially reduced graphene oxide (pRGO) – 6-aminonaphthalene-2-sulphonic acid (ANSA) hybrid nanomaterials. Au represents gold nanoparticles. The electrochemical sensing of NFX was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and differential pulse voltammetry (DPV). Experimental results show that the combination of MWCNT-CPE/pRGO-ANSA/Au offers high electrical conductivity, large surface area and excellent electrocatalytic activity, being beneficial for electrochemical sensing performance. The calibration curves of NFX exhibit linear response in the NFX concentration range of 0.03–1.0 and 1.0–50.0 μM, with the limit of detection (LOD) of 0.016 μM (S/N = 3). The fabricated sensors were successfully applied for detecting the presence of NFX in pharmaceutical formulations and rat plasma samples. The measured results were comparable with those obtained using ultrahigh performance liquid chromatography (UHPLC), indicating its high potential for applications in pharmaceutical analysis and clinical therapeutic drug monitoring.
研究领域:
分析化学
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药学
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临床医学
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高影响因子
MOLECULES
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2020
·Vol. 25
·期 2
·344
·
IF 3.267
Limin Qu,Ke Song,Qi Zhang,Jie Guo,Juan Huang
Tyrosinase inhibitors with excellent inhibitory activities and lower side effects have promising applications in the fields of medicine, agriculture, food sciences and cosmetics. In this study, a method for simultaneous separation and determination of six target compounds (puerarin, daidzin, genistein, daidzein, genistin, and formononetin) inPuerariae LobataeRadix was established by cloud point extraction (CPE) and concentration combined with high performance liquid chromatography (HPLC). To achieve high extraction yields, an ultrasound-assisted extraction method was developed based on a salt-modified Triton X-100 system. The optimal extraction conditions are: surfactant Triton X-100 concentration 0.07 g/mL, liquid-solid ratio 80:1 (mL/g), NaCl addition amount 0.6 g, equilibrium time 40 min, equilibrium temperature 70 °C. Under the optimal conditions, the total maximum extraction yield of the six target isoflavones reached 8.92 mg/g. Usingl-tyrosine andl-dopa as substrates, the effects of puerarin on the monophenolase and diphenolase activity of tyrosinase activity were investigated by the enzyme kinetics method. The results showed that puerarin inhibited monophenolase activity with an IC50of 0.537 mg/mL and activated diphenolase activity. The inhibition type of puerarin on monophenolase and the activation type of puerarin on diphenolase were analyzed by Lineweaver-Burk plots which show that puerarin showed mixed inhibition on monophenolase and mixed activation on diphenolase. Therefore, puerarin can be used as both a tyrosinase inhibitor and a tyrosinase activator.Keywords:Puerariae LobataeRadix;cloud point extractions;tyrosinase inhibitors;tyrosinase activator;kinetic analysis
研究领域:
药理学
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植物化学
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酶学
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PubMed
高影响因子
International Journal of Electrochemical Science
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2023
·
IF 1.5
Ruli Xu,Xiaomin Qian,Zhiyuan Zhang,Fanshu Yuan,Yuqing Song,Jie Liu,Qianli Zhang,Jie Wei
A sensitive and selective carbon paste electrode (CPE) for the detection of bisphenol A (BPA) was prepared using N doped multi-walled carbon nanotubes (N-MWCNT) as the electron transport accelerator and molecularly imprinted polymer (MIP) as the recognition element of BPA. In presence of the initiator of 2, 2′-azobis(isobutyronitrile) (AIBN), BPA was imprinted using acrylonitrile as a functional monomer and ethylene glycol dimethacrylate (EGDMA) as a cross-linker. The polymers of MIP and non-molecularly imprinted polymer (NIP) were characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Under the optimized conditions, the oxidation peak current increases linearly with the increase of BPA concentration in the range of 0.05 – 90 μmol/L (R = 0.9991), and the detection limit was 11.8 nmol/L. MIP/N-MWCNT/CPE successfully detected BPA in the elution solution of a plastic bottle.
研究领域:
分析化学
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环境科学
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材料科学
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电化学
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高影响因子
MICROCHEMICAL JOURNAL
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2024
·
IF 4.9
Yuvarajgouda N. Patil,Manjunath B. Megalamani,D.A. Ayush Gowda,Sharanappa T. Nandibewoor,Shivashankar Hiremath
This study focuses on developing a rapid, easy-to-use, and sensitive sensor for the electroanalytical detection of Metaxalone (MXL) for the first time. A novel sensor was created by combining sulfur-incorporated graphitic carbon nitride (S-GCN) with tungsten-doped titanium oxide nanoparticles (W: TiO 2 NPs) in a carbon paste, which was then loaded into a polytetrafluoroethylene (PTFE) tube. The synthesized modifiers were characterized using SEM, XRD, and FTIR techniques to understand their structural, morphological, and functional features, contributing to the electrocatalytic activity of the modified sensor (W: TiO 2 /S-GCN@CPE). Comparative analysis showed that W: TiO 2 /S-GCN@CPE achieved higher detection currents than the unmodified carbon paste electrode (CPE). Cyclic voltammetry (CV) and square wave voltammetry (SWV) were used to detect and quantify MXL electrochemically. The electrode’s physicochemical properties were studied under optimal conditions within a potential range of 0.3 V to 1.5 V. The W: TiO 2 /S-GCN@CPE showed a detection limit of 0.85 x 10 -8 M and demonstrated linearity over a concentration range of 0.1–100 x 10 -7 M. The sensor’s selectivity against interference from metal ions was also assessed. In practical applications, the developed electrode effectively detected MXL in spiked water, tablets, and biological samples, showing significant detection capacity and good recovery rates. Additionally, the electrode demonstrated stability across multiple measurements, positioning W: TiO 2 /S-GCN@CPE as a promising sensor for MXL detection.
研究领域:
分析化学
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环境科学
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生物医学工程
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高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
·
IF 7.312
Yao Zhang,Chao Wu,Huiming Zhu,Baoquan Zhang
Superhydrophobic materials for efficient separation of stabilized oil/water emulsions are in an urgent need to deal with an enormous amount of oily wastewater worldwide. The stainless steel mesh supported zeolitic imidazolate framework-7 (ZIF-7-coated SSM) was fabricated by way of secondary hydrothermal growth, it was further modified by using coordinated polysiloxane elastomer (CPE). Based on characterization by using SEM, XRD, FT-IR and contact angle measurements, the as-synthesized CPE-ZIF-7-coated SSM possessed a rough surface structure of microscale ravines with both superhydrophobicity and superoleophilicity. The stabilities of CPE-ZIF-7-coated SSM were investigated with respect to various treatments including high temperature, corrosion and ultrasonication. The self-healing ability and working mechanism of CPE-ZIF-7-coated SSM were explored by responding to continuous abrasion and O 2 plasma etching. The CPE-ZIF-7-coated SSM exhibited high water-in-oil emulsion separation efficiencies of over 99.9% with a remarkably fast self-healing ability upon damage in less than 10 min without any externally imposed input of matter/energy. The superhydrophobic CPE-ZIF-7-coated SSM with fast self-healing ability would be a promising alternative material for practical applications in separation of emulsive oil/water mixtures.
研究领域:
材料科学
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环境工程
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化学工程
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高影响因子
TALANTA
·
2021
·
IF 6.057
Wen-Jing Wei,Yuan Yang,Xin-Yuan Li,Peng Huang,Qiang Wang,Ping-Jian Yang
Silver Nanoparticles (Ag-NPs), an emerging type of pollutant, might occur various physical and chemical transformations, which would affect its environmental fate, transformation and biological effects. Sulfurization is the most common conversion of Ag-NPs, accompanied by the formation of nano-silver sulfide (Ag 2 S-NPs). The method of Ag 2 S-NPs analysis and characterization is of great significance for assessing the environmental risks of Ag. In this study, cloud point extraction (CPE) and Single Particle-Inductively Coupled Plasma-Mass Spectrometry (SP-ICP-MS) were used in combination to establish a simple and reliable analysis method to quantify Ag 2 S-NPs in water, with the morphology unchanged. Non-Ag 2 S-NPs were dissociated into Ag + firstly, and Ag 2 S-NPs and Ag + were separated by CPE, followed by SP-ICP-MS analysis. The extraction rate based on particle number concentration was between (76.19 ± 0.56) % to (106.35 ± 0.00) % in environmental waters. Compared with the (76.96 ± 2.18) nm Ag 2 S-NPs spiked, the particle size extracted increased slightly with (94.19 ± 2.72) nm- (97.25 ± 0.22) nm as the large-size Ag 2 S-NPs originally presented in waters, instead of agglomeration. This method could be generally applicable to the analysis of Ag 2 S-NPs in waters, and provide ideas for other metal sulfide nanoparticles (MS-NPs), which has certain significance.
研究领域:
环境科学
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分析化学
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PubMed
高影响因子
SENSORS
·
2024
·Vol. 24
·期 4
·1211
·
IF 3.4
Shimeng Sun,Qing Ma,Qiyu Sheng,Shangwei Huang,Chenxia Wu,Junsong Liu,Jia Xu
Amyloid plays a critical role in the pathogenesis of Alzheimer’s disease (AD) and can aggregate to form oligomers and fibrils in the brain. There is increasing evidence that highly toxic amyloid-β oligomers (AβOs) lead to tau protein aggregation, hyperphosphorylation, neuroinflammation, neuronal loss, synaptic loss, and dysfunction. Although the effects of AβOs on neurons have been investigated using conventional biochemical experiments, there are no established criteria for electrical evaluation. To this end, we explored electrophysiological changes in mouse hippocampal neurons (HT22) following exposure to AβOs and/or naringenin (Nar, a flavonoid compound) using electrical impedance spectroscopy (EIS). AβO-induced HT22 showed a decreased impedance amplitude and increased phase angle, and the addition of Nar reversed these changes. The characteristic frequency was markedly increased with AβO exposure, which was also reversed by Nar. The AβOs decreased intranuclear and cytoplasmic resistance and increased nucleus resistance and extracellular capacitance. Overall, the innovative construction of the eight-element CPE-equivalent circuit model further reflects that the pseudo-capacitance of the cell membrane and cell nucleus was increased in the AβO-induced group. This study conclusively revealed that AβOs induce cytotoxic effects by disrupting the resistance characteristics of unit membranes. The results further support that EIS is an effective technique for evaluating AβO-induced neuronal damage and microscopic electrical distinctions in the sub-microscopic structure of reactive cells.
研究领域:
神经科学
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生物物理学
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电生理学
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细胞生物学
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阿尔茨海默病研究
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PubMed
高影响因子
JOURNAL OF CLINICAL MICROBIOLOGY
·
2024
·Vol. 62
·期 2
·
IF 6.1
Zhimin Lu,Xiaonan Wang,Licai Ma,Leina Dou,Xiangjun Zhao,Jin Tao,Yang Wang,Shaolin Wang,Dejun Liu,Yingbo Shen,Xuezhi Yu,Wenbo Yu,Liangxi Jia,Zhanhui Wang,Jianzhong Shen,Kai Wen
Rapid phenotypic detection assays, including Carba NP and its variants, are widely applied for clinical diagnosis of carbapenemase-producing Enterobacterales (CPE). However, these tests are based on the acidification of the pH indicator during carbapenem hydrolysis, which limits test sensitivity and speed, especially for the detection of CPE producing low-activity carbapenem (e.g., OXA-48 variants). Herein, we developed a novel rapid and sensitive CPE detection method (Carba PBP) that could measure substrate (meropenem) consumption based on penicillin-binding protein (PBP). Meropenem-specific PBP was used to develop a competitive lateral flow assay (LFA) for meropenem identification. For the detection of carbapenemase activity, meropenem concentration was optimized using a checkerboard assay. The performance of Carba PBP was evaluated and compared with that of Carba NP using a panel of 94 clinical strains characterized by whole-genome sequencing and carbapenem susceptibility test. The limit of detection of PBP-based LFA for meropenem identification was 7 ng mL−1. Using 10 ng mL−1 meropenem as the substrate, Carba PBP and Carba NP could detect 10 ng mL−1 carbapenemase within 25 min and 1,280 ng mL−1 CPE in 2 h, respectively. The sensitivity and specificity were 100% (75/75) and 100% (19/19) for Carba PBP and 85.3% (64/75) and 100% (19/19) for Carba NP, respectively. When compared with Carba NP, Carba PBP showed superior performance in detecting all the tested CPE strains (including OXA-48-like variants) within 25 min and presented two orders of magnitude higher analytical sensitivity, demonstrating potential for clinical diagnosis of CPE.
研究领域:
微生物学
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临床诊断
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分子生物学
·
传染病
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DOI
PubMed
高影响因子
ANALYTICAL LETTERS
·
2020
·
IF 1.467
Jiajia Hong,Xiaotang Hao,Tiantian Liu,Weiting Liu,Meiyi Xie,Mei Wang,Qian Xu,Bingyi Yang
A sensitive method termed rapid synergistic cloud point extraction (RS-CPE) combined with partial least squares (PLS) was developed for the extraction and simultaneous determination of trace amounts of phenol and three detrimental chlorophenols (CPs) via a microplate assay (MPA). In this study, n-pentanol was used as a novel synergistic inducer and the linear nonionic surfactant Tergitol 15-S-7 was used as an extractant. The whole process of RS-CPE was accomplished in a few minutes without the need for the time-consuming water- or ice-bath steps used in traditional cloud point extraction. An automated and high-throughput assay using a 96-well plate allowed for the simultaneous processing of multiple samples with low sample volume requirements (approximately 200 µL). However, synchronized determination of several CPs using MPA method was problematic because of spectral interferences. Fortunately, a multivariate calibration method using PLS was applied to circumvent these limitations. Under the optimum conditions, the linear dynamic concentration ranges were from 0.5 to 15 µg/mL for 2-chlorophenol and 0.5 to 20 µg/mL for the other analytes. The detection limit range was from 0.275 to 0.419 µg/mL. The enrichment factor was up to 15.4 fold. The developed methodology was successfully applied to quantitative analysis of phenol and three CPs in water samples with recoveries from 90.0% to 109%.
研究领域:
分析化学
·
环境科学
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高影响因子
危险品化学品经营许可证（带存储）