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排序方式: 共有233条查询结果,搜索用时 31 毫秒
111.
Anodic stripping voltammetric determination of total lead, copper and selenium in whole blood and blood serum 总被引:1,自引:0,他引:1
A two-step procedure including appropriate wet-digestions, separation of selenium from interfering ions such as heavy metal
ions with pentyl alcohol and anodic stripping voltammetric (ASV) determination of Pb2+, Cu2+ and SeO3
2– is developed. The elements in digested whole blood and serum sample solutions were determined by using a standard addition
method. 1 × 10–9 mol/L SeO2–
3, Cu2+ and Pb2+ were successfully determined with relative standard deviations of approximately 1–2% (n = 6–8).
Received: 19 August 1996 / Revised: 24 February 1997 / Accepted: 28 February 1997 相似文献
112.
S. Ağan A. Çelik-Aktaş J.M. Zuo A. Dana A. Aydınlı 《Applied Physics A: Materials Science & Processing》2006,83(1):107-110
Germanosilicate layers were grown on Si substrates by plasma enhanced chemical vapor deposition (PECVD) and annealed at different temperatures ranging from 700–1010 °C for durations of 5 to 60 min. Transmission electron microscopy (TEM) was used to investigate Ge nanocrystal formation in SiO2:Ge films. High-resolution cross section TEM images, electron energy-loss spectroscopy and energy dispersive X-ray analysis (EDX) data indicate that Ge nanocrystals are present in the amorphous silicon dioxide films. These nanocrystals are formed in two spatially separated layers with average sizes of 15 and 50 nm, respectively. EDX analysis indicates that Ge also diffuses into the Si substrate. PACS 68.73.Lp; 61.46.Hk; 61.46.-w; 68.65.Hb; 61.82.Rx 相似文献
113.
Mustafa Hulusi Ugur Hasan Kılıç Mustafa Lütfü Berkem Atilla Güngör 《Chemical Papers》2014,68(11):1561-1572
UV-cured caprolactone-based polyurethane acrylate (PUA) polymer blend electrolytes were prepared and characterised. To develop polymer electrolytes suited to ambient temperature, an ionically-conductive and reliable polymer electrolyte based on urethane acrylate resins synthesised from a fluorine-containing di-functional oligomer 6F ethoxylated diacrylate, a di-functional reactive diluent 1,6-hexanediol diacrylate for adjusting the viscosity, and a radical photo-initiator doped with a mixture of lithium salts were used. Free-standing flexible electrolyte films were prepared by UV-curing via free-radical photopolymerisation. The performance of the lithium polymer cell system (Li/PE(F4)/LiCoO2) was determined by electrochemical impedance spectroscopy, cyclic voltammetry, a galvanostatic recurrent differential pulse, chronocoulometry and chronoamperometry. The electrolyte with optimal amounts of fluorine-containing oligomer and optimal salt mixture content exhibited enhanced conductivity, showing a conductivity of 1.00 × 10?4 S cm?1 at ambient temperature. The specific capacity, specific energy and specific power of a Li/PE(F4)/LiCoO2 cell were also determined. 相似文献
114.
Synthesis of Dihydropyrans and Dihydrofurans via Radical Cyclization of Unsaturated Alcohols and 1,3‐Dicarbonyl Compounds
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Hakan Aslan Deniz E. Akpınar Atilla Öktemer Mehtap Yakut Oğuzhan Alagöz 《Helvetica chimica acta》2014,97(5):652-663
The oxidative cyclization reactions of 1,3‐dicarbonyl compounds 1a – 1c and α,β‐unsaturated alcohols 2a – 2f with Mn(OAc)3 were performed, leading to dihydrofurans. Treatment of 1a and 1b with 2‐methylbut‐3‐en‐2‐ol ( 2a ) gave dihydrofurans 3aa and 3ba , and dihydropyrans 4aa and 4ba , as unexpected products. While the reaction of 2‐methylbut‐3‐yn‐2‐ol ( 2b ) with acetylacetone ( 1b ) yielded a bifuran, ethyl acetoacetate ( 1a ) led to a mixture of furan, bifuran, and salicylate derivatives. Besides, surprisingly, styryl‐substituted dihydrofurans were obtained from the reactions of 1,3‐dicarbonyl compounds and (3E)‐2,4‐diphenylbut‐3‐en‐2‐ol. The reaction mechanisms were proposed for the formation of the different products, considering intermediates in these reaction mixtures. 相似文献
115.
Duygu Aydın Tekdaş Ruslan Garifullin Berna Şentürk Yunus Zorlu Umut Gundogdu Ergin Atalar Ayse B. Tekinay Alexander A. Chernonosov Yusuf Yerli Fabienne Dumoulin Mustafa O. Guler Vefa Ahsen Ayşe Gül Gürek 《Photochemistry and photobiology》2014,90(6):1376-1386
The design and synthesis of a phthalocyanine – Gd‐DOTA conjugate is presented to open the way to novel molecular theranostics, combining the properties of MRI contrast imaging with photodynamic therapy. The rational design of the conjugate integrates isomeric purity of the phthalocyanine core substitution, suitable biocompatibility with the use of polyoxo water‐solubilizing substituents, and a convergent synthetic strategy ended by the use of click chemistry to graft the Gd‐DOTA moiety to the phthalocyanine. Photophysical and photochemical properties, contrast imaging experiments and preliminary in vitro investigations proved that such a combination is relevant and lead to a new type of potential theranostic agent. 相似文献
116.
Cemil İbiş Amaç Fatih Tuyun Gökşin Aydınlı 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2014-2023
The substituted products alkyl(aryl)thio-tetrahalo-3-nitrobuta-1,3-dienes 3a–b were obtained from the reactions of 1-bromo-1,2,4,4-tetrachloro-3-nitrobuta-1,3-diene (1) with thiols. Further reactions of the substituted product alkyl(aryl)thio-tetrahalo-3-nitrobuta-1,3-dienes 3a–b in dichloromethane reacted with piperazine derivatives and morpholine to generate 5a–b and 7a–l. The structures of the new compounds were determined by microanalysis and spectroscopic data. 相似文献
117.
In this paper, the Moufang-Klingenberg plane over a local alternative ring R of dual numbers is studied. It is shown that its collineation group is transitive on quadrangles. It is therefore shown that
the coordinatization of these Moufang-Klingenberg planes is independent of the choice of the coordinatization quadrangle.
Also, the concept of 6-figures is extended to these Moufang-Klingenberg planes and it is shown that any 6-figure corresponds
to only one inversible m ∈ R. 相似文献
118.
Mehmet Atilla Tasdelen 《European Polymer Journal》2011,(5):937-941
Poly(epsilon-caprolactone)/clay nanocomposites were prepared by copper(I) catalyzed azide/alkyne cycloaddition (CuAAC) “click” reaction. In this method, ring-opening polymerization of epsilon-caprolactone using propargyl alcohol as the initiator has been performed to produce alkyne-functionalized PCL and the obtained polymers were subsequently attached to azide-modified clay layers by a CuAAC “click” reaction. The exfoliated polymer/clay nanocomposites were characterized by X-ray diffraction spectroscopy, thermogravimetric analysis and transmission electron microscopy. 相似文献
119.
120.
In this study, a series of ultraviolet (UV)‐curable organic–inorganic hybrid coating materials containing phosphorus were prepared by sol–gel approach from acrylate end‐capped urethane resin, acrylated phenyl phosphine oxide oligomer (APPO), and inorganic precursors. TEOS and MAPTMS were used to obtain the silica network and Ti:acac complex was employed for the formation of the titania network in the hybrid coating systems. Coating performance of the hybrid coating materials applied on aluminum substrates was determined by the analysis techniques, such as hardness, gloss, impact strength, cross‐cut adhesion, taber abrasion resistance, which were accepted by international organization. Also, stress–strain test of the hybrids was carried out on the free films. These measurements showed that all the properties of the hybrids were enhanced effectively by gradual increase in sol–gel precursors and APPO oligomer content. The thermal behavior of the hybrid coatings was investigated by thermogravimetric analysis (TGA) analysis. The flame retardancy of the hybrid materials was examined by the limiting oxygen index (LOI); the LOI values of pure organic coating (BF) increased from 31 to 44 for the hybrid materials containing phosphorus (BF‐P:40/Si:10). The data from thermal analysis and LOI showed that the hybrid coating materials containing phosphorus have higher thermal stability and flame resistance properties than the organic polymer. Besides that, it was found that the double bond conversion values for the hybrid mixtures were adequate in order to form an organic matrix. The polycondensation reactions of TEOS and MAPTMS compounds were also investigated by 29Si‐NMR spectroscopy. SEM studies of the hybrid coatings showed that silica/titania particles were homogenously dispersed through the organic matrix. In addition, it was determined that the hybrid material containing phosphorus and silica showed fibrillar structure. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献