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The unsteady MHD boundary layer flow of a micropolar fluid near the forward stagnation point of a two dimensional plane surface
is investigated by using similarity transformations. The transformed nonlinear differential equations are solved by an analytic
method, namely homotopy analysis method (HAM). The solution is valid for all values of time. The effect of MHD and porous
medium, non dimensional velocity and the microrotation are presented graphically and discussed. The coefficient of skin friction
is also presented graphically. 相似文献
63.
Nanocrystalline perovskite oxide materials ABO3 (where A = Ba, Ca, Mg, Sr; and B = Ce, Mn, and Ti) have been synthesized via sol-citrate combustion and hydrothermal-based methods with and without surfactant under mild conditions. Metal-titanates (ATiO3) were prepared using synthesized anatase-TiO2 nanotube powder, metal hydroxide/chloride solutions, and NaOH as raw materials. The stoichiometric amount of all reactants were put in polytetrafluoroethylene (PTFE)-lined stainless steel digestion reactor and were kept in convention oven at desired reaction conditions like mole composition, pH, temperature, and time, in range A/Ti = 0.9–1.1, 10–12, 150–170 °C for 24–48 h, respectively. The nanocrystalline barium cerium oxide (BaCeO3) was synthesized using citric acid as polymerization agent in sol-combustion process, whereas barium manganite (BaMnO3) was prepared via hydrothermal process using polyethyl glycol surfactant as structure directing agent. Thermal stability, phase evolution, and morphology of synthesized products were characterized by thermogravimetry and differential thermal analysis, X-ray diffraction (XRD), and scanning electron microscopy (SEM). XRD results revealed that synthesized CaTiO3 and BaMnO3 nanorods had an orthorhombic perovskite and hexagonal structure, respectively; whereas, the nanoparticle morphologies of BaTiO3, Ba0.5Sr0.5TiO3, and MgTiO3, BaCeO3 perovskite oxides were found strongly depended on pH of the precursor solutions. SEM images showed variety of morphological structures ranging from nanostructured surface with distinct particles morphology to nanowires and nanorods (length varies from nano to several micrometers) and uniform diameter ~<100 nm, depending upon the hydrothermal reaction conditions. 相似文献
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Farha Naz Mohd Asad Pawan Malhotra Asimul Islam Faizan Ahmad Md Imtaiyaz Hassan 《Applied biochemistry and biotechnology》2014,172(6):2838-2848
Microtubule-associated protein/microtubule affinity-regulating kinase 4 (MARK4) is a member of the family Ser/Thr kinase and involved in numerous biological functions including microtubule bundle formation, nervous system development, positive regulation of programmed cell death, cell cycle control, cell polarity determination, cell shape alterations, cell division etc. For various biophysical and structural studies, we need this protein in adequate quantity. In this paper, we report a novel cloning strategy for MARK4. We have cloned MARK4 catalytic domain including 59 N-terminal extra residues with unknown function and catalytic domain alone in PQE30 vector. The recombinant MARK4 was expressed in the inclusion bodies in M15 cells. The inclusion bodies were solubilized effectively with 1.5 % N-lauroylsarcosine in alkaline buffer and subsequently purified using Ni–NTA affinity chromatography in a single step with high purity and good concentration. Purity of protein was checked on sodium dodecyl sulphate–polyacrylamide gel electrophoresis and identified by using mass spectrometry immunoblotting. Refolding of the recombinant protein was validated by ATPase assay. Our purification procedure is quick, simple and produces adequate quantity of proteins with high purity in a limited step. 相似文献
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Naz Mohammed Aghatabay Metin Tulu Mehmet Somer Durata Haciu Ayberk Yilmaz 《Structural chemistry》2008,19(1):21-32
1,3-bis(benzimidazol-2-yl)-2-thiapropane (L) ligand and its zinc halide ZnX2 (X = Cl, Br, I) complexes have been synthesized. The compounds were characterized using the elemental analysis, molar conductivity,
FT-Raman, FT-IR (mid i.r., far i.r.), 1H and 13C NMR spectra, and quantum chemical calculations performed with Gaussian 03 package program set. The optimized geometries
and vibrational frequencies of the ligand and [Zn(L)Cl2] complex were calculated using the DFT/B3LYP method with a 6–31g(d) basis set. The geometry optimization of [Zn(L)Cl2] yields a slightly distorted tetrahedral environment around Zn ion, while the molecule clearly reveals the Cs symmetry. The
molar conductivity data reveals that the complexes are neutral. The ligand is bidentate, via two of the imine nitrogen atoms
in the bis-imidazole ring units, and together with the monodentate coordination of the two halides to the metal centre. 相似文献
66.
The influence of heat transfer on the steady flow of a fourth‐grade fluid between two stationary parallel porous plates is studied. The flow is engendered under the application of a constant pressure gradient. The concept of homotopy analysis method is utilized for the series solution of the governing problem. Numerical solution has been also carried out. In addition, both analytic and numerical solutions are compared. The variations of embedded parameters into the solution are predicted through the graphical representations. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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S. Sayin T. Kohlhaas S. Veziroglu E.Ş. Okudan M. Naz S. Schröder E.I. Saygili Y. Açil F. Faupel J. Wiltfang O.C. Aktas A. Gülses 《Materials Today Chemistry》2020
Resorbable and volume-stable collagen matrices have been preferred as grafting materials for diverse clinical applications in recent years. On the other hand, there is always an existing risk of transmission of infection with the cells or the tissues of the graft in using such collagen matrices. Moreover, considering the economic aspects, there is also a need for cost-efficient alternative materials. In this sense, marine algae can be considered as alternatives since they represent vast and cheap source of potential biopolymers. This work covers a comprehensive cytocompatibility study of composite biopolymers derived from different types of marine algae. 相似文献
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Zari I. Shafiq Anum Rasool G. Sindhu Tabassum Naz Khan T. S. 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6913-6929
Journal of Thermal Analysis and Calorimetry - The present research is manifested to observe the impact of double stratification in the Marangoni convective flow of the Casson nanoliquid model... 相似文献
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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