排序方式: 共有208条查询结果,搜索用时 15 毫秒
41.
Masoud Salavati-Niasari Shirin Shafaie-Arani Mohammad Reza Ganjali Parviz Norouzi 《Transition Metal Chemistry》2006,31(7):964-969
12- and 13-Membered diaza dioxa Schiff-base nickel(II) complexes were successfully prepared in a nanoscale microreactor by
the template condensation of (1,8-diamino-3,6-dioxaoctane)nickel(II) complex with bifunctional diketones within the nanodimensional
pores of zeolite Y. The host–guest nanocatalyst (HGN); ([Ni((R2[12]1,3-dieneN2O2)]2+-NaY, [Ni(R2[13]1,4-dieneN2O2)]2+-NaY; R = H, Me and Ph) is catalytically very efficient as compared to other neat complexes for oxidation of cyclohexene with
molecular oxygen as oxidant in the absence of solvent at 70 °C, affording 2-cyclohexene-1-ol and 2-cyclohexene-1-one. 相似文献
42.
Reza Ojani Jahan-Bakhsh Raoof Banafsheh Norouzi 《Journal of Solid State Electrochemistry》2010,14(4):621-631
Conducting and stable poly (N-methylaniline) film was prepared by using the repeated potential cycling technique in aqueous solution containing N-methylaniline, sulfuric acid, and sodium dodecyl sulfate (SDS) at the surface of carbon paste electrode (CPE). The transition
metal ions of Co(ІІ) were incorporated to the polymer by immersion of the modified electrode in 0.1 M cobalt chloride solution
for 10 min. The electrochemical characterization of this modified electrode exhibits stable redox behavior of Co(ІІ)→Co(ІІІ) and formation of insoluble oxide/hydroxide cobalt species on the CPE surface. The modified electrode showed well-defined
and stable redox couples in alkaline aqueous solution. The modified electrode showed excellent electrocatalytic activity for
oxidation of hydrogen peroxide. The response of modified electrode toward the H2O2 oxidation was examined using cyclic voltammetry, differential pulse voltammetry, square wave voltammetry, and chronoamperometry.
This modified electrode has many advantages such as simple preparation procedure, good reproducibility, and high catalytic
activity toward the hydrogen peroxide oxidation. Such characteristics were explored for the specific determination of hydrogen
peroxide in cosmetics product sample, giving results in excellent agreement with those obtained by standard method. 相似文献
43.
M. R. Ganjali B. Larijani H. Shams S. Riahi F. Faridbod P. Norouzi 《Journal of Analytical Chemistry》2010,65(10):1052-1060
Dextromethorphan (DXM) is an antitussive (cough Hyj/UA suppressant) drug found in many cough medicines. Dextromethorphan has also found other uses
in medicine, ranging from pain relief to psychoactive applications. In this study, a potentiometric liquid membrane sensor
for simple and fast determination of dextromethorphan hydrobromide in pharmaceutical formulation and urine was constructed.
For the membrane preparation, DXM-tetraphenylborate complexes were employed as electroactive materials in the membrane. The
wide linear range (10−6–10−2 M), low detection limit (1 × 10−6 M), and fast response time (∼5 s) characterize the proposed sensors. Validation of the method shows suitability of the sensors
for applications in the determination of dextromethorphan hydrobromide in pharmaceutical formulation and urine. 相似文献
44.
Mohammad Reza Ganjali Hamid Khoshsafar Farnoush Faridbod Ali Shirzadmehr Mehran Javanbakht Parviz Norouzi 《Electroanalysis》2009,21(19):2175-2178
Room temperature ionic liquids (RTILs), 1‐n‐butyl‐3‐methylimidazolium tetrafluoroborate, [bmim]BF4, and multiwalled carbon nanotubes (MWCNTs) were used for improvement of a praseodymium carbon paste ion selective sensor response. [bmim]BF4 can be a better binder than mineral oils. MWCNTs have a good conductivity which helps the transduction of the signal in carbon paste electrode. The characteristics of these electrodes as potentiometric sensors were evaluated and compared with PVC membrane sensor. The results indicate that potentiometric sensor constructed with ionic liquid shows an increase in performance in terms of Nernstian slope, selectivity, response time, and response stability compared to Pr(III) PVC membrane sensor. 相似文献
45.
Hadi Farahani Parviz Norouzi Rassoul Dinarvand Mohammad Reza Ganjali 《Journal of separation science》2009,32(2):314-320
A simple and sensitive methodology based on liquid‐phase microextraction (LPME) followed by GC‐MS, was developed for the determination of trihalomethanes (THMs) in drinking water. A microdrop of organic solvent was floated on the surface of the aqueous sample and it was agitated for a desired time. Then, the sample vial was cooled by inserting it into an ice bath for 4 min. The solidified solvent was transferred into a suitable vial and immediately melted. The extract was directly injected into the GC. Microextraction efficiency factors were investigated and optimized: 7 μL 1‐undecanol microdrop exposed for 15 min floated on the surface of a 10.0 mL aqueous sample with the temperature of 60°C containing 3 M of NaCl and stirred at 750 rpm. Under the selected conditions, enrichment factors (EFs) up to 482‐fold, LOD of 0.03–0.08 μg/L (S/N = 3) and dynamic linear ranges of 0.10–100 μg/L were obtained. A reasonable repeatability (RSD < 8.6%, n = 8) with satisfactory linearity (r2 ? 0.9947) of results illustrated a good performance of the present method. The protocol proved to be rapid, cost‐effective, and is a green procedure for the screening purposes. 相似文献
46.
In this paper, we study generalized symmetric Finsler spaces. We first study some existence theorems, then we consider their
geometric properties and prove that any such space can be written as a coset space of a Lie group with an invariant Finsler
metric. Finally we show that each generalized symmetric Finsler space is of finite order and those of even order reduce to
symmetric Finsler spaces and hence are Berwaldian. 相似文献
47.
Mohammad Norouzi Mahmood Tajbakhsh Heshmatollah Alinezhad Azade Geran Urimi 《中国化学会会志》2008,55(3):508-511
Cetyltrimethylammonium peroxodisulfate (CTA)2S2O8 was quantitatively prepared and used for the deprotection of oximes, phenylhydrazones, semicarbazones and thiosemicarbazones to the corresponding carbonyl compounds in acetonitrile. Its agent is more efficient and has advantages over similar reagents in terms of the amount of oxidant, short reaction time, simple work up, and high yield. 相似文献
48.
Mahmood Norouzi Behrooz Zare Vamerzani Mahdi Davoodi Nazanin Biglari Mohammad Mohsen Shahmardan 《Rheologica Acta》2015,54(5):391-402
In this paper, an exact analytical solution for creeping flow of Bingham plastic fluid passing through curved rectangular ducts is presented for the first time. The closed form of axial velocity distribution, flow resistance ratio, and wall shear stress are derived using bounded Fourier transformation. An extensive investigation on mutual effects of Hedstrom number, curvature ratio, and aspect ratio is conducted. The results indicate that a drag reduction is caused in the flow field by increasing the Hedstrom number. It is shown that unlike the Newtonian creeping Dean flow, the critical aspect ratio (an aspect ratio in which the flow resistance ratio is independent from curvature ratio) does not exist at large enough Hedstrom numbers. Analytical solution also indicated that as Hedstrom number is increased, the value of Poiseuille number is enhanced, and unlike the Newtonian flows, the value of Poiseuille number is not zero at edges of cross section. 相似文献
49.
This study presents for the first time development of a highly selective and sensitive thulium(III) micro‐sensor. Theoretical calculations were conducted on a S‐N Schiff base [thiophene‐2‐carbaldehyde‐(7‐methyl‐1,3‐benzothiazol‐2‐yl) hydrazone] (TCMH) in order to obtain a clue about the tendency of TCMH to Tm(III) and some other metal ions. Then, TCMH was used as a membrane‐active component to prepare a Tm(III)‐selective polymeric membrane microelectrode. In line with the resulting data, the electrode exhibits a Nernstian response toward Tm(III) ions for a very wide concentration range (1.0×10?11–4.0×10?6 M) with a detection limit of 1.0×10?11 (ca. 1.5 ppt) and a very fast response time in the whole concentration range (<5 s). In addition, the results showed that the certain microelectrode could be applied in the pH range of 4.0–11.0 with a usage of more than one month without any considerable potential divergence. 相似文献
50.
Mohammad Reza Ganjali Simindokht Shirvani-Arani Parviz Norouzi Morteza Rezapour Masoud Salavati-Niasari 《Mikrochimica acta》2004,146(1):35-41
A novel PVC-based membrane sensor based on the Co(II)-salophen complex (CSC) is described. The electrode revealed a Nernstian response over a wide nitrite ion concentration range (1.0×10–6–1.0×10–1M). The detection limit of the sensor is 8.0×10–7M. The best performance was obtained with a membrane composition of 33% PVC, 61% ortho-nitrophenyloctyl ether, 3% cobalt(II)-salophen, and 3% hexadecyltrimethylammonium bromide. The potentiometric response of the sensor is independent of the pH of solution in the pH range 4.5–11.9. The electrode exhibits a very fast response time and good selectivity over a variety of common inorganic and organic anions, including fluoride, bromide, iodide, sulfite, nitrate, thiocyanate, thriiodide and perchlorate. The selectivity behavior of the proposed sensor shows substantial improvements compared to the previously reported electrodes for nitrite ion. The membrane sensor can be used for at least 2 months without any divergence in potential. The electrode was successfully applied to the monitoring of nitrite ion in water, sausage, flour, wheat, cheese and milk. 相似文献