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641.
Rasool Hashemi Jamal Barvestani 《Journal of Superconductivity and Novel Magnetism》2014,27(2):371-377
This paper presents the tunability of the high temperature superconducting (SC) point defect modes in a two-dimensional photonic crystal composed of circular cylinders on a square lattice. By some modifications on the plane wave expansion method, we have shown that the properties of the SC point defect modes strongly depend on the temperature and external magnetic fields. The superconductor type and the nearest-neighbor of the defect effects are further investigated. Comparison between SC and conventional defects show that the SC one has only a monopole profile for different values of the defect size, and has very low sensitivity on the disorders, which is an important feature from a manufacturing point of view. 相似文献
642.
Contrast Agents: Magnetically Decorated Multiwalled Carbon Nanotubes as Dual MRI and SPECT Contrast Agents (Adv. Funct. Mater. 13/2014)
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643.
Julie Tzu‐Wen Wang Laura Cabana Maxime Bourgognon Houmam Kafa Andrea Protti Kerrie Venner Ajay M. Shah Jane K. Sosabowski Stephen J. Mather Anna Roig Xiaoxing Ke Gustaaf Van Tendeloo Rafael T. M. de Rosales Gerard Tobias Khuloud T. Al‐Jamal 《Advanced functional materials》2014,24(13):1880-1894
Carbon nanotubes (CNTs) are one of the most promising nanomaterials to be used in biomedicine for drug/gene delivery as well as biomedical imaging. This study develops radio‐labeled, iron oxide‐decorated multiwalled CNTs (MWNTs) as dual magnetic resonance (MR) and single photon emission computed tomography (SPECT) contrast agents. Hybrids containing different amounts of iron oxide are synthesized by in situ generation. Physicochemical characterisations reveal the presence of superparamagnetic iron oxide nanoparticles (SPION) granted the magnetic properties of the hybrids. Further comprehensive examinations including high resolution transmission electron microscopy (HRTEM), fast Fourier transform simulations, X‐ray diffraction, and X‐ray photoelectron spectroscopy assure the conformation of prepared SPION as γ‐Fe2O3. High r2 relaxivities are obtained in both phantom and in vivo MRI compared to the clinically approved SPION Endorem. The hybrids are successfully radio labeled with technetium‐99m through a functionalized bisphosphonate and enable SPECT/CT imaging and γ‐scintigraphy to quantitatively analyze the biodistribution in mice. No abnormality is found by histological examination and the presence of SPION and MWNT are identified by Perls stain and Neutral Red stain, respectively. TEM images of liver and spleen tissues show the co‐localization of SPION and MWNTs within the same intracellular vesicles, indicating the in vivo stability of the hybrids after intravenous injection. The results demonstrate the capability of the present SPION–MWNT hybrids as dual MRI and SPECT contrast agents for in vivo use. 相似文献
644.
Abstract—A wind farm consists of large number of turbines, the earth grids of which are connected together. Under fault condition at one turbine, only limited numbers of turbines are impacted. This article analyzes the fault current distributions between wind turbine earth grids under fault conditions. Furthermore, it introduces the clustering technique, which limits the simulation requirements for the wind farm, thus reducing the cost and time of the design process. A case study is also included to validate the analyses. 相似文献
645.
Majid Rasouli Francois Bertrand Jamal Chaouki 《American Institute of Chemical Engineers》2015,61(2):384-394
Radioactive particle tracking is a nonintrusive technique that has been successfully used to study the flow dynamics in a wide range of reactors and blenders. However, it is still limited to the tracking of only one tracer at a time. A multiple radioactive particle tracking (MRPT) technique that can determine the trajectory of two free or restricted (attached to the same particle) moving tracers in a system is introduced. The accuracy (<5 mm) and precision (<5 mm) of the proposed technique is evaluated by tracking two stationary tracers and two moving tracers. The results confirm the reliability and validity of the MRPT technique when the two tracers have the same isotope and the distance between them is not too small (>2 cm). The tracking of two sticking tracers at the two ends of a cylindrical particle in a rotating drum is also considered to illustrate the potential of this characterization method. © 2014 American Institute of Chemical Engineers AIChE J, 61: 384–394, 2015 相似文献
646.
Branka Filipovic Snezana Lukic Dragana Mijac Marija Marjanovic-Haljilji Marko Vojnovic Jelena Bogdanovic Tijana Glisic Natasa Filipovic Jamal Al Kiswani Aleksandra Djokovic Suncica Kapor Slobodan Kapor Zoran Bukumiric Ana Starcevic 《International journal of molecular sciences》2021,22(24)
Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease which is characterized by extremely complex pathogenetic mechanisms and multifactorial etiology. Some of the many pathophysiological mechanisms involved in the development of NAFLD include oxidative stress, impaired mitochondrial metabolism, inflammation, gut microbiota, and interaction between the brain-liver-axis and the regulation of hepatic lipid metabolism. The new therapeutic approaches in the treatment of NAFLD are targeting some of these milestones along the pathophysiological pathway and include drugs like agonists of peroxisome proliferator-activated receptors (PPARs), glucagon-like peptide-1 (GLP-1) agonists, sodium/glucose transport protein 2 (SGLT2) inhibitors, farnesoid X receptor (FXR) agonists, probiotics, and symbiotics. Further efforts in biomedical sciences should focus on the investigation of the relationship between the microbiome, liver metabolism, and response to inflammation, systemic consequences of metabolic syndrome. 相似文献
647.
Sadaf Jamal Gilani Syed Sarim Imam Adil Ahmed Sanjay Chauhan Mohd. Aamir Mirza 《Drug development and industrial pharmacy》2013,39(11):1799-1806
AbstractA rapid, accurate, and sensitive reverse phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated for the estimation of Thymoquinone (TMQ) in API as well as in noisome. The chromatograms were developed with the mobile phase – water: 2-propanol: methanol (50:45:5 v/v/v) as a solvent system at 254?nm. The method was validated as per ICH guidelines for different parameters and the recovery of TMQ was calculated in developed niosomes. Further, TMQ loaded niosomes (TMQNIOS) were prepared and evaluated for different parameters. The optimized TMQNIOS (F3) was further evaluated for surface morphology, in vitro drug release, permeation study, and confocal laser scanning microscopic (CLSM) study. The method showed linearity range between 6.25 and 100?µg/ml with low detection limit and quantitation limit with a value of 2.08 and 6.25?µg/ml. The developed formulations showed the vesicle size and encapsulation efficiency in the range of 157.32?±?3.15 to 211.44?±?5.23?nm and 59.32?±?4.87 to 83.21?±?3.55%, respectively. The drug release result showed the significant higher release from TMQNIOS in compared to TMQDIS, and the release kinetics data showed Higuchi's equation with highest regression coefficient values. The permeation study and the confocal laser microscopy study further confirmed the enhancement in permeation of TMQ in the intestinal mucosa. 相似文献
648.
Jamal Asadpoor Rahmatollah Rahimi Kamran Akhbari Ali Morsali 《Journal of Inorganic and Organometallic Polymers and Materials》2010,20(4):755-760
Nanoparticles of a new potassium two-dimensional coordination polymer, {[K2(μ4-L)2(μ-H2O)4]n·nH2O} (1), HL = 3-{[(4-nitrophenyl)methylen]amino}benzoic acid} were synthesized from thermal treatment of compound 1 with oleic acid at 523 K. The nanoparticles were characterized by scanning electron microscopy and FT-IR spectroscopy. Compound 1 was structurally characterized by single-crystal X-ray diffraction. The crystal structure of this compound indicates that the coordination number for the potassium ions is seven. A hydrogen bonding network and π-π stacking interactions result in more stability of compound 1 crystal packing. The thermal stability of compound 1 was studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The results of stoichiometry studies and formation of compound 1 in MeCN solution were found to be in support of its solid state stoichiometry and show the 1:1 complex formation between the L− and K+ ion in MeCN solution. 相似文献
649.
This two-parts paper summarizes the experimental and theoretical results of a comprehensive and first of its kind study on the kinetics of carbon dioxide (CO2) absorption and desorption in and from aqueous solutions of monoethanolamine (MEA), diethanolamine (DEA), methyl-diethanolamine (MDEA) and 2-amino-2-methyl-1-propanol (AMP) and their mixtures (i.e., MEA+AMP, MEA+MDEA, DEA+AMP and DEA+MDEA). Part-1 of this paper presents a detailed design of the novel hemispherical apparatus and a rigorous mathematical model applicable to both absorption and desorption conditions with some preliminary results and Part-2 provides detailed results with estimates of kinetic coefficients for CO2 absorption and desorption for eight different aqueous amine systems.The new hemispherical contactor consists of a 76 mm diameter solid hemisphere housed in a Pyrex glass cylinder with appropriate gas and liquid feed and withdrawal systems. The liquid feed passes through a 4 mm ID tube, which is located in the center of the hemisphere, and discharges at the top. The liquid descends as a well-defined liquid film over the surface of the hemisphere and is collected by a funnel (79 mm ID) at the base of the hemisphere. The interfacial area and hydrodynamics are well defined and the entrance/exit effects as well as surface rippling are minimized. Using this apparatus, the absorption experiments were conducted at near atmospheric pressure with pure CO2 saturated with water vapor at 293-323 K with initially unloaded solutions and the desorption experiments were performed at 333-383 K for CO2 loadings between 0.02 and 0.7 moles of CO2 per mole of amine using humidified nitrogen gas as a stripping medium at total system pressures up to 205 kPa.The new rigorous mathematical model developed to interpret the rate data is based on the principle of diffusional mass transfer accompanied with liquid-phase chemical reactions over a hemispherical liquid film. Also developed in this work is a methodology that uses the rigorous model in conjunction with a non-linear regression technique to estimate kinetic parameters. Preliminary results presented in this part of the paper show that the new experimental apparatus was successful in accurately measuring and the new model and its numerical implementation were successful in accurately predicting both absorption and desorption rates for all aqueous amine systems considered in this study. 相似文献
650.