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61.
Hassan Ali Zamani Rahimi Fatemeh Naghavi‐Reyabbi Fatemeh Arvinfar Ali Imani Alihossien Reza Ganjali Mohammad Faridbod Farnoush Salavati‐Niasari Masoud 《中国化学》2011,29(7):1523-1528
A poly(vinyl chloride) (PVC) membrane sensor for holmium ions was fabricated based on N‐[(Z)‐1‐(2‐thienyl)‐ methylidene]‐N‐[4‐(4‐{[(Z)‐1‐(2‐thienyl)methylidene]amino} phenoxy)phenyl] amine (TPA) as a new ion carrier, acetophenon (AP) as plasticizing solvent mediator and sodium tetraphenyl borate (NaTPB) as an anion excluder. The electrode shows a good selectivity towards Ho3+ ions respect to other inorganic cations, including alkali, alkaline earth, transition and heavy metal ions. The constructed sensor displays a Nernstian behavior (19.5±0.3 mV/decade) over the concentration range of 1.0×10−6 to 1.0×10−2 mol·L−1 with the detection limit of the electrode being 4.6×10−7 mol·L−1 and very short response time (ca. 5 s). It has a useful working pH range of 3.2–9.8 for at least 8 weeks. The electrode was successfully applied as an indicator electrode for the potentiometric titration of a Ho3+ solution with EDTA and holmium determination in some alloys. The proposed sensor accuracy was studied by the determination of Ho3+ in mixtures of three different ions. 相似文献
62.
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64.
Nano-TiO2 as an eco-friendly and efficient nanocatalyst was applied for quinoxaline preparation with improved yield.In this protocol,diketones and 1,2-diamines were condensed in the presence of catalyst at room temperature. 相似文献
65.
Mohamad Javad Tahmasebi Birgani Fatemeh Seif Nahid Chegeni Mohamad Reza Bayatiani 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1367-1370
In consideration the radiological properties of materials and studying the scattering processes in atomic and nuclear physics,
the effective atomic and mass numbers is widely employed. These numbers have been calculated for any mixed or composite materials
in interaction with high energy photons (Linac in radiation therapy). A pair equation in terms of these numbers is obtained.
The first equation has been derived from the conservation of mass energy law and the second by minimizing the binding energy
from the semiempirical mass formula (Myers and Swiatecki formula) that gives a relation between atomic and mass numbers for
stable nuclei approximately. By these equations one can obtain the effective atomic and mass numbers for any compound or mixed
materials uniquely. These numbers are calculated for some materials and compared with the other studies. 相似文献
66.
67.
Majid M. Heravi Samaheh Sadjadi Sodeh Sadjadi Hossein A. Oskooie Fatemeh F. Bamoharram 《Ultrasonics sonochemistry》2009,16(6):718-720
Bis(indolyl)alkanes have been synthesised in excellent yields in the presence of catalytic amount of silica-supported Preyssler nano particles as green, reusable and efficient catalyst under ultra sonic irradiation. 相似文献
68.
A straightforward and modular preparative approach to 1,3,5-triaroylbenzene-based functionalized cyclophane ring systems has been developed. The key cyclophane-forming macrocyclization reaction was accomplished during the course of a regioselective cross-benzannulation between bis(aryl ethynyl) ketone and enaminone reactants. Macrocyclic products with ring sizes ranging from 18- to 22-membered were successfully constructed. The composition of the tether connecting the two aryl ethynyl ketone fragments can be easily varied; consequently, this method is suitable for construction of a diverse range of structurally distinct cyclophane products. To illustrate this feature, cyclophanes possessing xylyl, alkyl, di(ethylene triamine), and di(ethylene oxy) bridging units were synthesized in isolated yields of 11-46%. Three new cyclophanes (calixarene-like macrocyles 8 and 9, as well as crownophane 18) were structurally characterized by X-ray diffractometry. 相似文献
69.
A unique combination of a supported cobalt complex and the first example of supported NHPI in acetic acid gives a surprisingly stable heterogeneous catalytic system for the selective aerobic oxidation of methylaromatics to benzaldehydes at atmospheric pressure. 相似文献
70.
A simple, precise, sensitive and accurate method was developed for rapid determination of trace quantities of periodate. The method is based on the accelerating effect of periodate on the reaction of bromate and hydrochloric acid in the presence of hydrazine. The decolorization of methyl orange with the reaction products was used to monitor the reaction spectrophotometrically at 525 nm. Periodate could be determined in the concentration ranges of 0.02–1.5 g/mL. The relative standard deviation for ten replicate determinations of 0.3 g/mL of periodate was 1.12%. The method was applied to the determination of periodate in water samples and indirect determination of ethylene glycol in gasoline and glycerol in vegetable oil via Malaprade reaction with satisfactory results. 相似文献