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排序方式: 共有163条查询结果,搜索用时 15 毫秒
91.
Mahnaz M. Abdi Nur Farhana Waheeda Mohd Azli Naz Chaibakhsh Hong Ngee Lim Paridah Md Tahir Gholamreza Karimi Mohammad Khorram 《Journal of polymer science. Part A, Polymer chemistry》2021,59(5):428-438
A dopamine (DA) biosensor was developed based on polypyrrole/tannin/cetyltrimethylammonium bromide (PPy/TA/CTAB) nanocomposite and central composite rotatable design (CCRD) was employed for the optimization of conditions. Chemical polymerization of the PPy/TA in the presence of a cationic surfactant, CTAB, reduced the particle size of composite and a rod-like structure with a lumpy surface and high porosity was observed for nanocomposite justifying the highest current response for the modified electrode. Amperometry and differential pulse voltammetry analyses were applied for all electrochemical measurements and DA detection in the range of 0.5–100 μM. The good adhesion of nanocomposite on the electrode surface, as well as porosity and high surface area of the modified electrode, enhanced the diffusion of DA molecules inside the matrix. Amperometry analysis of the Screen printed carbon electrode/PPy/TA/CTAB modified electrode displayed a good sensitivity of 0.039 μA (μM)−1 toward DA with the limit of detection of 2.9 × 10–7 M. The modified biosensor also excludes the interfering species of ascorbic acid and uric acid which makes this sensor appropriate for DA determination. The proposed biosensor showed an acceptable reproducibility and repeatability with low relative standard deviations of 4.8% and 4.4%, respectively. 相似文献
92.
The article studies the application of the extended Fan sub-equation method to \((1+1)\)-dimensional nonlinear dispersive modified Benjamin-Bona-Mahony equation with fractional evolution. This equation describes the hydromagnetic waves in cold plasma, acoustic waves in inharmonic crystals and acoustic gravity waves in compressible fluids. The structure of the extended Fan sub-equation method on the basis of time-fractional derivative is presented. The main idea of the method is to take full advantage of the general elliptic equation involving five parameters. The fractional derivatives are taken as in the sense of Jumarie’s modified Riemann–Liouville derivative. The method is reliable and gives more general exact solutions than the existing methods. 相似文献
93.
The synthesis of a metal–organic framework (MOF) named IITI‐1 is reported by employing an H2L linker with Cu(NO3)2?3 H2O in a mixed solvent system of N,N‐dimethyl formamide (DMF) and H2O. Further, in order to explore the energy storage application of IITI‐1 , a IITI‐1/CNT hybrid was prepared by a simple ultrasonication technique. Incorporation of a carbon nanotube (CNT) in the layered IITI‐1 MOF gave rise to enhanced electrolyte accessibility along with improved electrochemical storage capacity. The electrochemical investigations reveal a high specific capacitance (380 F g?1 at 1.6 A g?1) with a good rate performance for IITI‐1/CNT . The IITI‐1 MOF and the IITI‐1/CNT composite were characterized by PXRD, BET, SEM, and TEM techniques. Moreover, IITI‐1 MOF was also confirmed by single‐crystal XRD analysis. 相似文献
94.
The novel characteristics of magnetic field and entropy generation in mixed convective flow of Carreau fluid towards a stretched surface are investigated.Buongiornio nanoliquid model consists of thermophoresis and Brownian movement aspects is opted for analysis.Energy expression is modeled subject to thermal radiation and viscous dissipation phenomenon.Concentration by zero mass flux condition is implemented.Consideration of chemical reaction and activation energy characterizes the mass transfer mechanism.Total entropy generation rate and Bejan number is formulated.The utilization of transformation variables reduces the PDEs into non-linear ODEs.The obtained nonlinear complex problems are computed numerically through Shooting scheme.The impact of involved variables like local Weissenberg number,magnetic parameter,thermal radiation parameter,Brownian motion parameter,thermophoresis parameter,buoyancy ratio parameter,mixed convection parameter,Prandtl parameter,Eckert number,Schmidt number,non-dimensional activation energy parameter,chemical reaction parameter,Brinkman number,dimensionless concentration ratio variable,diffusive variable and dimensionless temperature ratio variable on velocity,temperature,nanoparticles concentration,entropy generation,Bejan number,surface drag force and heat transfer rate are examined through graphs and tables. 相似文献
95.
In this paper, the first integral method is applied to solve the Korteweg–de Vries equation with dual power law nonlinearity and equation of microtubule as nonlinear RLC transmission line. This method is manageable, straightforward and a powerful tool to find the exact solutions of nonlinear partial differential equations. 相似文献
96.
Ampleford DJ Lebedev SV Ciardi A Bland SN Bott SC Hall GN Naz N Jennings CA Sherlock M Chittenden JP Palmer JB Frank A Blackman E 《Physical review letters》2008,100(3):035001
The first laboratory astrophysics experiments to produce a radiatively cooled plasma jet with dynamically significant angular momentum are discussed. A new configuration of wire array z pinch, the twisted conical wire array, is used to produce convergent plasma flows each rotating about the central axis. Collision of the flows produces a standing shock and jet that each have supersonic azimuthal velocities. By varying the twist angle of the array, the rotation velocity of the system can be controlled, with jet rotation velocities reaching approximately 18% of the propagation velocity. 相似文献
97.
Generating relations involving two variable laguerre polynomials Ln(x, y) are derived. The process involves the construction of a three-dimensional Lie algebra isomorphic to special linear algebra sl(2) with the help of Weisner's method by giving suitable interpretations to the index n of the polynomials Ln(x, y). 相似文献
98.
Dr. Johannes Moll Dr. Robert Naumann Lukas Sorge Dr. Christoph Förster Niklas Gessner Lukas Burkhardt Naz Ugur Prof. Dr. Patrick Nuernberger Prof. Dr. Wolfram Seidel Dr. Charusheela Ramanan Prof. Dr. Matthias Bauer Prof. Dr. Katja Heinze 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(57):e202201858
Increasing the metal-to-ligand charge transfer (MLCT) excited state lifetime of polypyridine iron(II) complexes can be achieved by lowering the ligand's π* orbital energy and by increasing the ligand field splitting. In the homo- and heteroleptic complexes [Fe(cpmp)2]2+ ( 12+ ) and [Fe(cpmp)(ddpd)]2+ ( 22+ ) with the tridentate ligands 6,2’’-carboxypyridyl-2,2’-methylamine-pyridyl-pyridine (cpmp) and N,N’-dimethyl-N,N’-di-pyridin-2-ylpyridine-2,6-diamine (ddpd) two or one dipyridyl ketone moieties provide low energy π* acceptor orbitals. A good metal-ligand orbital overlap to increase the ligand field splitting is achieved by optimizing the octahedricity through CO and NMe units between the coordinating pyridines which enable the formation of six-membered chelate rings. The push-pull ligand cpmp provides intra-ligand and ligand-to-ligand charge transfer (ILCT, LL'CT) excited states in addition to MLCT excited states. Ground and excited state properties of 12+ and 22+ were accessed by X-ray diffraction analyses, resonance Raman spectroscopy, (spectro)electrochemistry, EPR spectroscopy, X-ray emission spectroscopy, static and time-resolved IR and UV/Vis/NIR absorption spectroscopy as well as quantum chemical calculations. 相似文献
99.
100.
Wasim Ul Bari Najeeb Ur Rehman Ajmal Khan Sobia Ahsan Halim Ye Yuan Mark A.T. Blaskovich Zyta M. Ziora Muhammad Zahoor Sumaira Naz Riaz Ullah Amal Alotaibi Ahmed Al-Harrasi 《Molecules (Basel, Switzerland)》2021,26(7)
In the study, two novel compounds along with two new compounds were isolated from Grewia optiva. The novel compounds have never been reported in any plant source, whereas the new compounds are reported for the first time from the studied plant. The four compounds were characterized as: 5,5,7,7,11,13-hexamethyl-2-(5-methylhexyl)icosahydro-1H-cyclopenta[a]chrysen-9-ol (IX), docosanoic acid (X), methanetriol mano formate (XI) and 2,2’-(1,4-phenylene)bis(3-methylbutanoic acid (XII). The anticholinesterase, antidiabetic, and antioxidant potentials of these compounds were determined using standard protocols. All the isolated compounds exhibited a moderate-to-good degree of activity against acetylcholinesterases (AChE) and butyrylcholinesterase (BChE). However, compound XII was particularly effective with IC50 of 55 μg/mL (against AChE) and 60 μg/mL (against BChE), and this inhibitory activity is supported by in silico docking studies. The same compound was also effective against DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid) radicals with IC50 values of 60 and 62 μg/mL, respectively. The compound also significantly inhibited the activities of α-amylase and α-glucosidase in vitro. The IC50 values for inhibition of the two enzymes were recorded as 90 and 92 μg/mL, respectively. The in vitro potentials of compound XII to treat Alzheimer’s disease (in terms of AchE and BChE inhibition), diabetes (in terms of α-amylase and α-glucosidase inhibition), and oxidative stress (in terms of free radical scavenging) suggest further in vivo investigations of the compound for assessing its efficacy, safety profile, and other parameters to proclaim the compound as a potential drug candidate. 相似文献