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In the aim of further research of the highly bioactive benzofuran and triazine derivatives, the synthesis of 1,2,4-triazine derivatives bearing the benzofuran moiety has been undertaken. Using a simple and convenient method, a three steps synthesis of novel functionalized 1,2,4-triazine derivatives from readily available starting materials has been described. Herein, two derivatives of 1,2,4-triazine were obtained in moderate yields. The structures of all synthesized compounds were elucidated by spectral methods of analysis

Acrobot, which is also called gymnastic robot, is a single input-multi output (SIMO) system which imitates motion of a barbell athlete. However, two links of this model are just equivalent to body and hand of athlete. To imitate better motion of athlete, three-linked acrobot- a complicated multi input-multi output (MIMO) under-actuated system – is developed. Parts of barbell athlete including leg, body and hand, are modelled well by this new system. In this paper, we present a method to apply an 81-rule fuzzy algorithm, which is popularly used for invert pendulum systems, to balance this model at upward equilibrium point. Instead of using a complicated 729-rule fuzzy controller which is set by knowledge of experts, we use more simple fuzzy structure. Through genetic algorithm (GA), the pre-processing and post-processing coefficients of fuzzy controller are chosen. With these suitable coefficients, our fuzzy controller is proved to work well through Matlab/Simulink simulation.

In the further research and synthesis of hybrid molecules which exhibit highly biological activities, the synthesis of triazole-fused bicyclic heterocycles bearing the benzofuran has been undertaken. A facile, convenient and good yielding synthesis of novel benzofuran-bearing 1,2,4-trazole derivatives were described. Herein, two derivatives of [1,2,4]triazolo[3,4-b][1,3,4]thiadiazole were synthesized from salicylaldehyde in four steps in moderate to good yields. Structures of all the targeted synthesized compounds were elucidated by spectral methods of analysis

Corncob (CC) is one of the high-yield agricultural by-products used for recycling in many fields. Corncob-based biochar (CCB) is considered a potentially low-cost adsorbent. The article aims to describe the structural and morphological changes of CCB under different pyrolysis temperatures (350oC, 450oC, and 550 oC) and duration (30, 60, and 90 minutes). Using the FTIR, SEM, BET, and BJH analysis, the evolution of the changes in the properties of CCBs was evaluated. FTIR spectra showed that the surface of CCBs contained abundant carbon-containing in functional groups such as an alkane, aromatic ring, are suitable for binding pollutants in solution. It might be concluded that the CCB550/90 can be a potential adsorbent due to possessing the highest surface area (127.295 m2.g-1), total pore volume (0.080 cm3.g-1) and the heterogeneous structure. The preliminary experiment result also showed that CCB550/90 had the highest phosphate adsorption capacity with 9.799 mg.g-1 in the stock solution, and removed up to 98% of phosphate. The new research results could be used to further biochar studies or even apply to the large-scale production of adsorbents.

This work presented the removal of nitrate ions in aqueous solution based on silica nanoparticles (SiNPs), which were extracted from rice husk ash. The optimal conditions for nitrate ion adsorption were studied including pH, contact time, adsorbate concentration, and amount of absorbance. The surface morphological analysis showed that the SiNPs extracted (purity of 98%) were around 50 nm with a surface area of 30 m2·g−1 and adsorption average pore width of 2.72 nm, offers possibility for high capability of nitrate ion removal. The experimental results showed that the nitrate ion capability of adsorption was obtained around 14.22 mg·g−1 with a concentration range from 0 to 25 mg·L−1 based on optimizing conditions including pH 6, contact time of 50 minutes, and SiNP dosage of 0.15 g vol−1. In addition, nitrate ion removal based on SiNPs will provide considerate benefits such as the reducing costly sample pretreatment steps, less time-consuming, and reliable methods for processing nitrate-polluted water.

This research deals with the influences of macro, meso and micro steel-smooth fibers on tensile and compressive properties of strain-hardening fiber-reinforced concretes (SFCs). The different sizes, indicated by length/diameter ratio, of steel-smooth fiber added in plain matrix (Pl) were as follows: 30/0.3 for the macro (Ma), 19/0.2 for the meso (Me) and 13/0.2 for the micro fiber (Mi). All SFCs were used the same fiber volume fraction of 1.5%. The compressive specimen was cylinder-shaped with diameter × height of 150 × 200 mm, the tensile specimen was bell-shaped with effective dimensions of 25 × 50 × 100 mm (thickness × width × gauge length). Although the adding fibers in plain matrix of SFCs produced the tensile strain-hardening behaviors accompanied by multiple micro-cracks, the significances in enhancing different mechanical properties of the SFCs were different. Firstly, under both tension and compression, the macro fibers produced the best performance in terms of strength, strain capacity and toughness whereas the micro produced the worst of them. Secondly, the adding fibers in plain matrix produced more favorable influences on tensile properties than compressive properties. Thirdly, the most sensitive parameter was observed to be the tensile toughness. Finally, the correlation between tensile strength and compressive strength of the studied SFCs were also reported. Keywords: aspect ratio; strain-hardening; post-cracking; ductility; fiber size.

In this work, the multilayer of the surface plasmon resonance (SPR) sensor was optimized to achieve the maximum sensor sensitivity. By optimizing the thickness of the silver layer (Ag) and dielectric films (TiO2 and AlAs), the optimum sensitivity of the SPR sensor could be obtained. The performance of the SPR sensor proposed was compared with control simulations utilizing zinc oxide (ZnO) and molybdenum oxide (MoO3). The numerical results indicate that the figure-of-merits (FOM) of the SPR sensor was achieved around 150/RIU, corresponding to the sensor sensitivity of 162.79°/RIU with the optimized thicknesses of the TiO2, Ag, and AlAs layers of 140 nm, 60 nm, and 25 nm, respectively. This refractive index sensor shows the FOM to have high detection accuracy and high sensitivity that lead to finding potential application in bio-chemical detection with a small volume of liquid used in biological diagnosis.

Adsorption is an efficient, cost-effective, and eco-friendly method for the treatment of phosphorus from wastewater. This work presents the adsorptive removal of phosphate ions in aqueous solution ...

This brief review presents the recent process in optical sensors based on surface plasmon resonance (SPR). In particular, it will focus on the optical sensors that employ the change of refractive index as the sensing transduction signal. Various detection schemes of optical sensors which include phase modulation, wavelength modulation and intensity modulation are discussed. The performance advantageous and disadvantageous of the description of optical sensors structure and their respective experimental configurations are also described. The examples of detection in chemistry, biology and heavy metals will be presented. Future prospects of surface plasmon resonance (SPR) sensing technology is also discussed.

In this work, SiO2 nanoparticles were prepared by the sol-gel method after sodium silicate was extracted from rice husk ash (RHA) under various experimental conditions such as types of acids, NaOH concentration, dissolved time, and temperature and used for removal of Fe2+ ions from aqueous solutions. The extracted SiO2 was morphologically and chemically characterized and showed a surface area of 78 m2/g and uniform pores of 2.71 nm, offering high adsorption capacity for Fe2+ ions. The influence of pH, contact time, and amount of adsorbent was studied in order to establish the best conditions for the Fe2+ adsorption and removal. Furthermore, the adsorption data were fitted with an exponential shape curve for all the three variable parameters that affect the adsorption process. The best results were obtained for pH 5, 20 min contact time, and 0.5 g adsorbent dose. The loading adsorption capacity was 9 mg of Fe2+ ions/g SiO2 in the concentration range 0.1–1.0 mgL−1. In addition, the synthesized SiO2 with the size of around 50 nm can be used for specific heavy metal removal and drug delivery, after modification of the SiO2 surface with various functional groups.

Carbon dioxide (CO2) accounts for the most significant proportion of greenhouse gas emissions, progress towards decrease the existence of atmospheric CO2 have received considerable attention. Therefore, focus on carbon capture and utilization, which reduces the content of CO2 and provides an excellent solution to generate value-added and renewable fuels. Herein, the electrochemical CO2 reduction activity of Ag@ZnO@rGO electrocatalysts prepared by facile synthesis route has been systematically investigated. The good incorporation of Ag in the ZnO NPs matrix (Ag@ZnO) was synthesized through the thermal calcination of Ag+-impregnated ZIF8. Then, Ag@ZnO was coated by rGO using a hydrothermal technique. We found that the efficiency of electrochemical CO2 reduction is highly dependent on the porosity and conductivity properties. The effective interaction of rGO in Ag-based ZnO porous nanoparticles showed high activity, leading to reach Faradaic efficiencies of about 70% at −1.6 V vs. SCE. To the best of our knowledge, the performance in this work is comparable to the literature. Additionally, the electrocatalyst stays for more than 30 min without any significant change of activity, possessing the ability for applications to reducing CO2.

In this work, SiO2 nanoparticles were prepared by the sol-gel method after sodium silicate was extracted from rice husk ash (RHA) under various experimental conditions such as types of acids, NaOH concentration, dissolved time, and temperature and used for removal of Fe2+ ions from aqueous solutions. The extracted SiO2 was morphologically and chemically characterized and showed a surface area of 78 m2/g and uniform pores of 2.71 nm, offering high adsorption capacity for Fe2+ ions. The influence of pH, contact time, and amount of adsorbent was studied in order to establish the best conditions for the Fe2+ adsorption and removal. Furthermore, the adsorption data were fitted with an exponential shape curve for all the three variable parameters that affect the adsorption process. The best results were obtained for pH 5, 20 min contact time, and 0.5 g adsorbent dose. The loading adsorption capacity was 9 mg of Fe2+ ions/g SiO2 in the concentration range 0.1–1.0 mgL−1. In addition, the synthesized SiO2 with the size of around 50 nm can be used for specific heavy metal removal and drug delivery, after modification of the SiO2 surface with various functional groups.

We present a real-time quantitative immunoassay to detect fibrinogen in the blood plasma of Alzheimer’s disease patients using multimode fiber optical sensors in which surface plasmon resonance (SPR) was employed. Nanometer-thick bimetals including silver and aluminum were coated onto the core surface of the clad-free part (5 cm long) of the fiber for SPR excitation at the He-Ne laser wavelength of 632.8 nm. The histidine-tagged peptide was then coated on the metal surface to immobilize the fibrinogen antibody for the selective capture of fibrinogen among the proteins in the patient blood plasma. The SPR fiber optical sensor enabled quantitative detection of concentrations of fibrinogen from the different human patient blood at a detection limit of ∼20 ng/ml. We also observed a correlation in the fibrinogen concentration measurement between enzyme-linked immunosorbent assay and our SPR fiber-based sensors. This suggests that the presented SPR fiber-based sensors that do not rely on the use of labels such as fluorophores can be used for a real-time quantitative assay of a specific protein such as fibrinogen in a human blood that is known to contain many other kinds of proteins together.

We present the immunoassay of tau proteins (total tau and phosphorylated tau) in human sera using surface plasmon resonance (SPR) fiber sensors. This assay aimed at harvesting the advantages of using both SPR fiber sensors and a blood-based assay to demonstrate label-free point-of-care-testing (POCT) patient-friendly assay in a compact format for the early diagnosis of Alzheimer's disease (AD). For conducting the assay, we used human sera of 40 subjects divided into halves, which were grouped into AD patients and control groups according to a number of neuropsychological tests. We found that on an average, the concentrations of both total tau and phosphorylated tau proteins (all known to be higher in cerebrospinal fluid (CSF) and the brain) turned out to be higher in human sera of AD patients than in controls. The limits of detection of total tau and phosphorylated tau proteins were 2.4 pg mL−1 and 1.6 pg mL−1, respectively. In particular, it was found that the AD group exhibited average concentration of total tau proteins 6-fold higher than the control group, while concentration of phosphorylated tau proteins was 3-fold higher than that of the control. We can attribute this inhomogeneity between both types of tau proteins (in terms of increase of control-to-AD in average concentration) to un-phosphorylated tau proteins being more likely to be produced in blood than phosphorylated tau proteins, which possibly is one of the potential key elements playing an important role in AD progress.

International audience; The synthesis of triaryl methanols was investigated by reacting different 4-metalated 2-substituted pyrimidines with diaryl ketones, the latter being generated by deprotocupration-aroylation of azine and diazine substrates. Cyclization of the triaryl methanols thus obtained afforded pyrido[3’,2’:4,5]pyrrolo[1,2-c]pyrimidines, which were evaluated for kinase inhibition and antiproliferative activities in melanoma cells.

Tan Tai Nguyen,1 Sun Oh Bea,1 Dong Min Kim,2 Won Jung Yoon,3 Jin-Won Park,4 Seong Soo A An,1 Heongkyu Ju1,5,6 1Department of Bionano Technology, College of Bionano Technology, Gachon University, Seongnam, 2Department of Materials Science and Engineering, Hongik University, Sejong City, 3Department of Chemical and Bio Engineering, Gachon University, Seongnam, 4Department of Chemical and Biomolecular Engineering, College of Energy and Biotechnology, Seoul National University of Science and Technology, Seoul, 5Department of Nanophysics, College of Bionano Technology, Gachon University, Seongnam, 6Neuroscience Institute, Gil Hospital, Incheon, South Korea Purpose: We present the regenerative label-free fiber optical biosensor that exploits surface plasmon resonance for quantitative detection of fibrinogen (Fbg) extracted from human blood plasma.Materials and methods: The sensor head was made up of a multimode optical fiber with its polymer cladding replaced by metal composite of nanometer thickness made of silver, aluminum, and nickel. The Ni layer coated allowed a direct immobilization of histidine-tagged peptide (HP) on its metal surface without an additional cross-linker in between. On the coated HP layer, immunoglobulin G was then immobilized for specific capturing of Fbg.Results: We demonstrated a real-time quantitative detection of Fbg concentrations with limit of detection of ~10ng/mL. The fact that the HP layer could be removed by imidazole with acid also permitted us to demonstrate the regeneration of the outermost metal surface of the sensor head for the sensor reusability.Conclusion: The sensor detection limit was estimated to be ~10pM, which was believed to be sensitive enough for detecting Fbg during the clinical diagnosis of cardiovascular diseases, myocardial infarction, strokes, and Alzheimer’s diseases. Keywords: SPR, real-time assay, histidine-tagged peptide, protein sensing

International audience; An experimental program was set up to study the suffusion process by using a triaxial erodimeter developed in our laboratory. This device is equipped with a multichannel optical sensor in order to characterize precisely the initiation and development of suffusion process. With the objective to characterize the erodibility of clayey sand, tests were performed under either flow-rate-controlled or hydraulic-gradient-controlled conditions. The test analysis allows distinguishing three steps. First, suffusion of a small quantity of clay is detected on downstream. In flow-rate-controlled conditions, this suffusion is immediately followed by a high increase of the hydraulic gradient which continues during the second step. The second step is characterized by very low amount of particles in the effluent. During the third step, high suffusion of clay appears and induces erosion of clay and sand. The results reveal the necessity to take into account the evolutions of hydraulic gradient (or pressure gradient) and also the evolutions of velocity (or flow rate) to represent the hydraulic loading. The analysis based on energy expended by fluid flow and eroded mass permits to characterize the soil sensitivity to clay suffusion and clayey sand erosion for tests under the two types of hydraulic loading.; Un programme expérimental est réalisé afin d’étudier le processus de suffusion en utilisant un érodimètre triaxial développé au sein de notre laboratoire. Cet appareillage est équipé d’un capteur optique polychromatique afin de caractériser précisément l’initiation et le développement du processus de suffusion. Avec l’objectif de déterminer la sensibilité à l’érosion d’un sable argileux, des essais sont menés à débits imposés ou à gradients hydrauliques imposés. L’analyse des essais permet de distinguer trois étapes. Tout d’abord la suffusion d’une faible quantité d’argile est détectée à l’aval. A débit imposé, cette suffusion est immédiatement suivie par une forte augmentation du gradient hydraulique qui se poursuit au cours de la deuxième étape. La deuxième étape est également caractérisée par la présence d’une très faible quantité de particules dans l’effluent. Pendant la troisième étape, une importante suffusion d’argile apparaît et elle précède une érosion de sable argileux. Les résultats soulignent la nécessité de prendre en compte les évolutions du gradient hydraulique (ou du gradient de pression) et également celles de la vitesse (ou du débit) pour représenter le chargement hydraulique. L’analyse basée sur la détermination de l’énergie dissipée par le fluide interstitiel et la masse érodée permet de caractériser la sensibilité du sol à la suffusion d’argile et à l’érosion de sable argileux pour les essais menés suivant les deux types de chargement hydraulique.

International audience; Deprotonative cupration of aromatics including heterocycles (anisole, 1,4-dimethoxybenzene, thiophene, furan, 2- fluoropyridine, 2-chloropyridine, 2-bromopyridine and 2,4-dimethoxypyrimidine) was realized in tetrahydrofuran at room temperature using the Gilman-type amido-cuprate (TMP)2CuLi in situ prepared from CuCl2*TMEDA through successive addition of 1 equivalent of butyllithium and 2 equivalents of LiTMP. The intermediate lithium (hetero)arylcuprates were evidenced by trapping with iodine, allyl bromide, methyl iodide and benzoyl chlorides, the latter giving the best results. Symmetrical dimers were also prepared from lithium azine and diazine cuprates using nitrobenzene as oxidative agent.

We present a surface plasmon resonance (SPR) based multimode fiber sensor with non-golden bimetallic coating. Our detection scheme used, which is capable of measuring the combined effects of SPR-induced birefringence and intensity changes, supported the minimum resolvable refractive index (RI) of 5.8 x 10(-6)RIU with the operating RI range of 0.05 to be experimentally obtained at a single wavelength (632.8 nm) without non-spectroscopic techniques. The asymmetric profile of the thickness of the bimetal coating on the fiber core together with the inherent range of incidence angle for multimode propagation also contributed to the wide operating range. The SPR fiber device with the detection scheme demonstrated will be likely to be developed as a real-time label-free and highly sensitive diagnostic device of a wide operating range for biomedical and biochemical applications in a portable format. (C)2014 Optical Society of America

La rapidité de mémorisation des techniques numériques permet d'accélérer les mesures et de suivre les évolutions des phénomènes de surfaces.