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281.
Akram-Sadat Tabatabaei-Panah Mahmood Jeddi-Tehrani Roya Ghods Mohammad-Mehdi Akhondi Nazanin Mojtabavi Ahmad-Reza Mahmoudi Ebrahim Mirzadegan Sorour Shojaeian Amir-Hassan Zarnani 《Journal of fluorescence》2013,23(2):293-302
Here we introduce novel optical properties and accurate sensitivity of Quantum dot (QD)-based detection system for tracking the breast cancer marker, HER2. QD525 was used to detect HER2 using home-made HER2-specific monoclonal antibodies in fixed and living HER2+ SKBR-3 cell line and breast cancer tissues. Additionally, we compared fluorescence intensity (FI), photostability and staining index (SI) of QD525 signals at different exposure times and two excitation wavelengths with those of the conventional organic dye, FITC. Labeling signals of QD525 in both fixed and living breast cancer cells and tissue preparations were found to be significantly higher than those of FITC at 460–495 nm excitation wavelengths. Interestingly, when excited at 330–385 nm, the superiority of QD525 was more highlighted with at least 4–5 fold higher FI and SI compared to FITC. Moreover, QDs exhibited exceptional photostability during continuous illumination of cancerous cells and tissues, while FITC signal faded very quickly. QDs can be used as sensitive reporters for in situ detection of tumor markers which in turn could be viewed as a novel approach for early detection of cancers. To take comprehensive advantage of QDs, it is necessary that their optimal excitation wavelength is employed. 相似文献
282.
Mohammad Hossein Tavakoli Talaye Arjmand Abasi Shirin Omid Ebrahim Mohammadi‐Manesh 《Crystal Research and Technology》2013,48(2):58-68
In this paper, for an inductively heated Czochralski furnace used to grow sapphire single crystal, influence of the inner (wall‐to‐wall) and crystal internal (bulk) radiation on the characteristics of the growth process such as temperature and flow fields, structure of heat transfer and crystal‐melt interface has been studied numerically using the 2D quasi‐steady state finite element method. The obtained results of global analysis demonstrate a strong dependence of thermal field, heat transport structure and crystal‐melt interface on both types of radiative heat transfer within the growth furnace. 相似文献
283.
Reza Ojani Jahan-Bakhsh Raoof Ebrahim Zarei Seyed Naser Azizi Maryam Abrishamkar 《Monatshefte für Chemie / Chemical Monthly》2012,40(8):7-12
Abstract
This paper describes microwave-assisted synthesis of a new MFI-type zeolite, Zeolite Secony Mobile (ZSM-5), its characterization by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM), and its application for fabrication of a modified carbon paste electrode. This novel electrode was employed for sensitive and simultaneous determination of dopamine and uric acid at biological pH (pH 7.0). The results show that this zeolite-modified carbon paste electrode significantly improves the electron transfer rate and reduces the overpotential of dopamine and uric acid oxidation without any fouling effect due to deposition of their oxidized products. The linear analytical curves were obtained in the ranges of 9.0 × 10−6–4.9 × 10−4 and 8.0 × 10−6–9.0 × 10−4 M for dopamine and uric acid, respectively, by using differential pulse voltammetry based on oxidation of these biomolecules. The detection limits (2σ) were determined for dopamine and uric acid as 7.9 × 10−6 and 7.1 × 10−6 M, respectively. This method has been successfully employed for quantification of dopamine and uric acid in real samples. 相似文献284.
Khadijeh Rezaee Ebrahim Saraee M. M. Gharipour M. R. Abdi F. Majidi 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):811-815
The street children phenomenon is an increasing problem in most cities of the world including Isfahan, which is a fast growing
town. The number of street children with the growth of the town is increased. It is therefore important to have baseline data
on their health problems. Hair element analysis remains an important tool in the nutritional and environmental assessment
of them. A measurement of the elemental concentration in recently-grown hair provides an integrated view of the element status
in the follicular cells and their blood supply, unaffected by short term fluctuations in the nutrient intake of the subject.
This study aimed to assess heavy metals concentrations in the hair of street children in Isfahan using neutron activation
analysis method. The concentration of heavy metals (Cu, Cr, Fe, Hg, Mn, and Zn) of 17 Iranian street children (Isfahan) was
examined. Data analysis found that different profiles of the concentrations of Cr, Hg, Mn, and Zn were seen in each sample.
These results were discussed with reference to show of environmental effects. 相似文献
285.
A novel electrode was prepared by forming TiO2 thin films using a commercially available TiO2 powder (Degussa P25) on graphite plates for water photoelectrocatalytic decontamination. In addition to, for the first time the photoelectrochemical degradation of 3,4‐dichlorophenol was investigated. The effects of applied potential, pH, and initial 3,4‐dichlorophenol concentration on the photoelectrocatalytic (PEC) degradation of 3,4‐dichlorophenol using ultraviolet (UV) illuminated TiO2/graphite (TiO2/C) thin film electrode was examined and discussed. Also, direct photolysis (DP), electrochemical oxidation (EC), photocatalytic (PC) and photoelectrocatalytic (PEC) degradation of 3,4‐dichlorophenol were compared. Results show that the best responses for PEC are obtained at applied potential 1.2 V versus reference electrode, pH 8.0 and initial 3,4‐dichlorophenol concentration 6.7 mg L?1. 相似文献
286.
Naguib AM Ebrahim ME Aly HF Metawaa HM Mahmoud AH Mahmoud EA Ebrahim FM 《Natural product research》2012,26(23):2196-2198
This research was performed to investigate in?vitro the biological activities of successive as well as 70% ethanol extracts of Nepeta cataria on some biochemical parameters including oxidative markers and carbohydrate-hydrolysing enzyme activities (α-amylase, β-galactosidase and α-glucosidase). Powdered N. cataria and its successive extracts were screened for their phytochemical constituents. Tests for tannins, carbohydrates, glycosides and flavonoids were positive in ethanolic extract, but those for steroids and terpenoids were positive in petroleum ether and chloroform extracts. Also, different extracts were chromatographically investigated. The results obtained demonstrated that different successive extracts of N. cataria exhibited an inhibitory effect on oxidative stress indices and carbohydrate-hydrolysing enzymes. It is observed that 70% ethanol, petroleum ether and chloroform extracts showed, respectively, the most potent inhibitory activities, while ethyl acetate and ethanol successive extracts appeared with moderate or low reducing activities. 相似文献
287.
Ebrahim Alizadeh Kurosh Sedighi Mousa Farhadi H.R. Ebrahimi-Kebria 《Communications in Nonlinear Science & Numerical Simulation》2009,14(2):462-472
The Adomian decomposition method (ADM) can provide analytical approximation or approximated solution to a rather wide class of nonlinear (and stochastic) equations without linearization, perturbation, closure approximation, or discretization methods. In the present work, ADM is employed to solve the momentum and energy equations for laminar boundary layer flow over flat plate at zero incidences with neglecting the frictional heating. A trial and error strategy has been used to obtain the constant coefficient in the approximated solution. ADM provides an analytical solution in the form of an infinite power series. The effect of Adomian polynomial terms is considered and shows that the accuracy of results is increased with the increasing of Adomian polynomial terms. The velocity and thermal profiles on the boundary layer are calculated. Also the effect of the Prandtl number on the thermal boundary layer is obtained. Results show ADM can solve the nonlinear differential equations with negligible error compared to the exact solution. 相似文献
288.
Fixed point and coincidence results are presented for single-valued generalized -weakly contractive mappings on complete metric spaces , where is a lower semicontinuous function with and for all and is a function such that is nonempty and closed. Our results extend previous results given by Rhoades (2001) [1] and by Zhang and Song (2009) [2]. 相似文献
289.
Aliphatic and aromatic alcohols are efficiently oxidized to ketones or carboxylic acids using aqueous hydrogen peroxide as an oxidant in the presence of a Mn(III) Schiff-base complex as a catalyst under solvent-free conditions. The oxidation of alcohols occurred at 50 °C to give the corresponding ketones or carboxylic acids with a yield higher than 60%. 相似文献
290.
Mansoor Anbia Seyyed Ebrahim Moosavi Fard Korosh Shafiei Mohammad Ali Hassanzadeh Abbas Mayahipour 《中国化学》2012,30(4):842-846
Vanadium doped nanoporous Ti0.9Sn0.1O2 thin film has been prepared on an alumina substrate by sol‐gel method with Pluronic P123 as the organic template, and humidity sensing properties of it has been investigated. It is found that V‐doped nanoporous Ti0.9Sn0.1O2 thin film shows good humidity sensing properties, and impendence of it decreases more than four orders of magnitude in the relative humidity (RH) range of 11%–95% at 25°C. The response and recovery time of this sensor are about 13 and 17 s, respectively. High sensitivity, narrow hysteresis loop, rapid response and recovery, prominent stability and good repeatability are obtained. A possible mechanism is suggested to explain the humidity sensitive properties. 相似文献