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101.
Herein, we report the development of a robust, sensitive, and selective non‐enzymatic electrochemical sensor for the detection of hydrogen peroxide (H2O2). The novel BA modified CN‐dot wrapped Cu2O‐nano‐frogspawn (FS@CN‐dot) sensor probe demonstrated a catalytic property towards H2O2 that allowed the highly sensitive electrochemical detection at a low reduction potential. The as prepared CN‐dot wrapped Cu2O hetero‐structured nanocomposite was analyzed using surface analysis methods to confirm the morphology, crystallinity, and oxidation states of various constituents and dopant elements. Further, the morphological analysis of the Cu2O nanoparticles revealed that the Cu2O retains frogspawns‐liked structure. Under the optimized experimental conditions, the sensor showed a wide dynamic range of H2O2 from 0.5 μM to 9 mM with a detection limit (LD) of 1.2±0.1 nM. The designed sensing probe showed good stability, high sensitivity, and selectivity even in the presence of potential interfering molecules. To check the reliability of the fabricated sensor in biomedical applications, the proposed sensing probe was successfully applied to monitor H2O2 in saliva of a gum‐diseased patient. To the best of our knowledge, this report is the first of its kind not only because of its novel construction style in terms of CN source, but also in terms of real sample applicability as well.  相似文献   
102.
A novel electrode based on orange peel derived C‐dots decorated CuO nanorods (CR@C‐dot) modified lead pencil (LP) electrode has been fabricated for highly sensitive and selective monitoring of dopamine (DA). Prior to the functionalization with C‐dot, electrochemical efficacy of CR was evaluated and compared with CuO nano‐needles (CN) and nano‐spheres (CS). The morphology, surface area and composition of synthesized nanoparticles was confirmed through field emission scanning electron microscopy (FE‐SEM), N2‐adsorption‐desorption isotherm, X‐ray diffraction (XRD), Raman spectroscopy and X‐ray photoelectron spectroscopy (XPS). Our results indicated that CR has high electrocatalytic activity compared to CN and CS by expositing greater fraction of catalytic active sites, large surface area and short diffusion pathways. The electrochemical efficacy of CR is further enhanced by decorating with orange peel derived C‐dots, which surprisingly lead to the integrations of surface‐active sites with current collectors with minimum resistance by acting as an electron transport mediator and providing more surface defects. The developed CR@C‐dot sensor enables highly sensitive and selective recognition of DA detection (0.0007 μM), over good linear range (5–2250 μM) with rapid response time. the developed CR@C‐dot sensor was successfully used to monitor the DA from deboned chicken, thus suggesting reliability of the developed electrode.  相似文献   
103.
Gelatin-gum arabic spherical multinuclear microcapsules (SMMs) encapsulating peppermint oil were prepared by complex coacervation. Transglutaminase (TG) was used to harden the SMMs by complex coacervation instead of traditional reagents such as formaldehyde or glutaraldehyde. The effect of various cross-linking parameters on the hardening effectiveness of SMMs containing peppermint oil was investigated. The optimum parameters were as follows: hardening for 6h at 15 degrees C and pH 6.0 with a TG concentration of 15 U/g gelatin. Compared with formaldehyde, TG exhibits similar microcapsule hardening effectiveness.  相似文献   
104.

Peristaltic pumping of Sisko fluid through the non-uniform asymmetric channel is addressed. Main motivations are given to nonlinear radiation and inclined magnetic field. The perturbation technique and lubrication approach are utilized for development of governing problems and solutions. Resulting equations are solved for velocity, temperature, pressure and stream function. Trapping phenomenon is also observed. Variation of pertinent parameters is plotted and illustrated physically. The larger inclination of the magnetic field leads to a rise in velocity. Moreover, the size of trapping bolus tends to reduce and finally disappears for the larger fluid parameter. To our knowledge, such attempt for linear radiation and without inclined magnetic field does not exist even for both symmetric and asymmetric channels. Further it should be noted that problem remains nonlinear even after utilizing long wavelength and low Reynolds number assumptions.

  相似文献   
105.

The present study elaborates three-dimensional (3D) thermally radiative flow of carbon nanotubes dispersed in water with Darcy–Forchheimer porous space. A bidirectional linear stretchable sheet is used to generate the flow. Darcy–Forchheimer relation specifies porous space. Single-wall carbon nanotubes and multi-wall carbon nanotubes are accounted. Solutions development is due to optimal homotopy analysis technique. Optimal data of sundry variables are obtained. The optimal solution interpretations of velocities and temperature are interpreted via plots. Physical quantities are also elaborated. Our results reveal that thermal field against radiation and temperature ratio parameter is enhanced.

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106.
The synthetic strategy is based on alkylation of 4-aryl-N-(4-chlorophenyl)-6-methyl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxamide derivatives IV a–g , with some alkyl halides and α-haloketones, namely, methyl iodide, chloroacetonitrile, and phenacyl bromide to give the corresponding S-substituted derivatives Va–c . Treatment of IVa–c with ethyl bromoacetate in ethanol under reflux in the presence of potassium hydroxide solution led to the formation of N-(4-chlorophenyl)-7-methyl-3-oxo-5-(aryl)-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidine-6-carboxamide derivative VIII a–c in a single-step synthesis. On the other hand, compound IVa reacted with α-halo carbonitriles, namely, chloro acetonitrile, and monobromo malononitrile, to produce directly thiazolo[3,2-a]pyrimidine derivatives Xa and Xb , respectively, Compound Xb also reacted with each of formic acid, formamide, and ammonium thiocyanate to form thiazolodipyrimidine derivatives XI–XIII , respectively. Compound VIIIa–c coupled with arenediazonium salts in pyridine to give the corresponding 2-arylhydrazo derivatives XVIa–e . Compounds IV a–g and VIIIa–c were resynthesized under microwave irradiation. Some of the newly synthesized compounds were tested for their antimicrobial activities.  相似文献   
107.
The present analysis comprises the steady two-dimensional magnetohydrodynamic flow of an upper-convected Maxwell fluid near a stagnation-point over a stretching surface. The governing non-linear partial differential equation for the flow are reduced to an ordinary differential equation by using similarity transformations. The analytic solution of nonlinear system is constructed in the series form using Homotopy analysis method. Convergence of the obtained series is discussed explicitly. The effects of the sundry parameters on the velocity profile is shown through graphs. The values of skin-friction coefficient for different parameters is tabulated.  相似文献   
108.
This article looks into the unsteady rotating magnetohydrodynamic (MHD) flow of an incompressible second grade fluid in a porous half space. The flow is induced by a suddenly moved plate in its own plane. Both the fluid and plate rotate in unison with the same angular velocity. Analytic solution of the governing flow problem is obtained by using Fourier sine transform. Based on the modified Darcy's law, expression for velocity is obtained. The influence of pertinent parameters on the flow is delineated and appropriate conclusions are drawn. Several existing solutions of Newtonian fluid have been also deduced as limiting cases.  相似文献   
109.
Riccati equation approach is used to look for exact travelling wave solutions of some nonlinear physical models. Solitary wave solutions are established for the modified KdV equation, the Boussinesq equation and the Zakharov-Kuznetsov equation. New generalized solitary wave solutions with some free parameters are derived. The obtained solutions, which includes some previously known solitary wave solutions and some new ones, are expressed by a composition of Riccati differential equation solution...  相似文献   
110.
Coronopus didymus (Brassicaceae) commonly known as lesser swine cress has been reported to be used for its pharmacological activities. This study aimed to evaluate the medicinal potential of C. didymus extracts against cancer, diabetes, infectious bacteria and oxidative stress and the identification of bioactive compounds present in these extracts. The effects of using different solvents for the extraction of C. didymus on the contents of major polyphenols and biological activities were investigated. Plant sample was shade dried, ground to a fine powder, and then soaked in pure acetone, ethanol and methanol. The highest contents of major polyphenols were found in methanol-based extract, i.e., chlorogenic acid, HB acid, kaempferol, ferulic acid, quercetin and benzoic acid with 305.02, 12.42, 11.5, 23.33, 975.7 and 428 mg/g of dry weight, respectively, followed by ethanol- and acetone-based extracts. The methanol-based extract also resulted in the highest antioxidant activities (56.76%), whereas the highest antiproliferative (76.36) and alpha glucosidase inhabitation (96.65) were demonstrated in ethanol-based extracts. No antibacterial property of C. didymus was observed against all the tested strains of bacteria. Further studies should be focused on the identification of specific bioactive compounds responsible for pharmacological activities.  相似文献   
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