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排序方式: 共有103条查询结果,搜索用时 15 毫秒
21.
Suna Wang Dacheng Li Jianmin Dou Daqi Wang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(4):m118-m121
In the title coordination compound, catena‐poly[[[bis[diaquacadmium(II)]‐μ2‐trans‐1,2‐bis(4‐pyridyl)ethene]bis{μ2‐2,2′‐[(5‐carboxymethoxy‐m‐phenylene)dioxy]diacetato}] trans‐1,2‐bis(4‐pyridyl)ethene solvate dihydrate], {[Cd2(C12H10O9)2(C12H10N2)(H2O)4]·C12H10N2·2H2O}n, (I), each CdII centre adopts a pentagonal–bipyramidal coordination geometry. The incompletely deprotonated 2,2′‐[(5‐carboxymethoxy‐m‐phenylene)dioxy]diacetate (TCMB) ligands and trans‐1,2‐bis(4‐pyridyl)ethene (bpe) ligands both act as bidentate bridges, linking the CdII centres into one‐dimensional ladders, which are connected into an undulating two‐dimensional (6,3) layer through O—H...N hydrogen bonds between the carboxylate groups of the TCMB ligands and the N atoms of the uncoordinated bpe ligands. Each undulating layer polycatenates two other identical layers, exhibiting the unusual combination of both 2D → 2D parallel and 2D → 3D parallel interpenetration (2D and 3D are two‐ and three‐dimensional, respectively). 相似文献
22.
Zinc porphyrin-appended dendrimers, 12PZn, 18PZn, 24PZn, and 36PZn, containing 12, 18, 24, and 36 zinc porphyrin units, respectively, were synthesized using zinc porphyrin dyad (2PZn) and triad (3PZn) as precursors. Although these dye-functionalized dendrimers all serve as chiroptical sensors for an asymmetric bipyridine (RR- and SS-Py2), the sensing capability is highly dependent on the structure of the dendritic scaffold. 2PZn, which is chiroptically silent toward Py2, turns cooperative and displays a large ICD (induced circular dichroism) response in the visible region when incorporated into 12PZn. Judging from the extents of contribution of each zinc porphyrin unit to the CD amplitudes ([Deltaepsilonmax]), the cooperativity in 24PZn (112 M-1 cm-1) is lower than that in 12PZn (196 M-1 cm-1) and much lower in dendron 4PZn (59 M-1 cm-1). In contrast, 3PZn, which is ICD-active toward Py2, hardly shows such an enhanced cooperativity when incorporated into 18PZn and 36PZn and dendron 6PZn, as well. Absorption spectroscopy suggests some unique conformational characteristics of the zinc porphyrin units in highly cooperative 12PZn. 相似文献
23.
24.
Shao Yong Li Bei Sun Zhi Chao Xiao Ming Hui Huang Wei Xue Xie Jun Min Liu 《中国化学快报》2009,20(6):640-642
A one-step procedure is developed to synthesize inherently chiral p-tert-butylcalix[4]azacrown 1 through etherification between p-tert-butylcalix[4]arene and compound 3, which can be amplified to efficiently prepare more inherently chiral calix[4]arenes in ABHH substitution pattern. 相似文献
25.
26.
Gorkem Yilmaz Hojjat Toiserkani Dilek Odaci Demirkol Serhan Sakarya Suna Timur Yusuf Yagci Lokman Torun 《Journal of polymer science. Part A, Polymer chemistry》2011,49(1):110-117
Well‐defined amphiphilic graft copolymer with hydrophobic polysulfone (PSU) backbone and hydrophilic poly(acrylic acid) (PAA) side chains were synthesized and characterized. For this purpose, commercially available PSU was converted to azido‐functionalized polymer (PSU‐N3) by successive chloromethylation and azidation processes. Independently, poly(tert‐butyl acrylate) (PtBA) with an alkyne‐end‐group is obtained by using suitable initiator in atom transfer radical polymerization (ATRP). Then, this polymer was successfully grafted onto PSU‐N3 by click chemistry to yield polysulfone‐graft‐poly(tert‐butyl acrylate), (PSU‐g‐PtBA). Finally, amphiphilic polysulfone‐graft‐poly(acrylic acid), (PSU‐g‐PAA), membranes were obtained by hydrolyzing precursor the PSU‐g‐PtBA membranes in trifluoroacetic acid. The final polymer and intermediates at various stages were characterized by 1H NMR, FTIR, GPC, and SEM analyses. Protein adsorption and eukaryotic and prokaryotic cell adhesion on PSU‐g‐PAA were studied and compared to those of PSU‐g‐PtBA and unmodified PSU. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
27.
Rufen Zhang Zhengsong Hu Qianli Li Peizhen Yan Suna Wang Chunlin Ma 《Heteroatom Chemistry》2014,25(4):217-225
Six new arenetelluronic triorganotin esters, namely (R3Sn)4[ArTe(μ‐O)(OH)O2)]2 (Ar = Ph, R = Me: 1 , R = Ph: 2 ; Ar = 3‐Me‐Ph, R = Me: 3 , R = Ph: 4 , Ar = 3‐Cl‐Ph, R = Me: 5 , R = Ph: 6 ), were prepared by treating arenetelluronic acids with the corresponding R3SnCl (R = Me, Ph) with potassium hydroxide in methanol. All complexes were characterized by elemental analysis, FT‐IR, NMR (1H, 13C, 119Sn) spectroscopy, and X‐ray crystallography. The structural analyses indicate that these complexes are isostructural as Sn4Te2 moiety, in which the Te2(μ2‐O)2 units are situated in the center and each Te atom is coordinated with two OSnR3 groups on the side. Complexes 1 , 3 , and 5 show one‐dimensional chain and two‐dimensional network supramolecular structures by intermolecular C H···O or C H···Cl interactions. The antitumor activities of these complexes reveal that most arenetelluronic triorganotin esters have powerful antitumor activities with certain regularity. 相似文献
28.
Feriha Ozkaya Perihan Unak E. Ilker Medine Serhan Sakarya Gülcan Unak Suna Timur 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(3):1789-1796
18FDG conjugated magnetic iron oxide nanoparticles (MNPs) were synthesized as PET-MR hybrid imaging agent. Synthesized and characterized NPs were then applied to MCF-7 human breast cancer cells. 18FDG conjugated MNPs exhibited the cell incorporation ratio up to 30 %. As well as the characterization studies, apoptotic effects were observed depending on the cellular incorporations by the time. In conclusion, synthesized structures could have a potential as hybrid imaging agent in PET-MR imaging systems besides apoptotic effect on cancer cells. 相似文献
29.
Simge Balaban Ceren Durmus Eda Aydindogan Zinar Pinar Gumus Suna Timur 《Electroanalysis》2020,32(1):128-134
Endogenous steroids such as dehydroepiandrosterone (DHEA) and dehydroepiandrosterone 3‐sulfate (DHEA?S) have commonly used as doping materials by athletes and to date novel techniques are needed for detection of these molecules. In this study, antibody‐based electrochemical biosensor has developed for testing level of the DHEA?S. For this aim, gold surfaces were initially modified with cysteamine (Cys) and then, DHEA?S antibody was immobilized on the surface via glutaraldehyde (GA) as a crosslinking agent. The stepwise modification of electrode surface was monitored by using various electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Linear range was determined as 2.5–100 ng/mL DHEA?S using differential pulse voltammetry (DPV) technique, as well. Moreover, repeatability (±S.D.), coefficient of variation (%) and limit of detection (LOD) values were calculated as 0.033, 1.030 and 3.971, respectively. Also, DHEA?S in synthetic serum and urine samples were successfully determined with standard addition method and confirmation analysis were performed with liquid chromatography quadrupole‐time of flight mass spectrometry (LC‐QTOF/MS) system. The selectivity was studied with the addition of some interfering molecules (testosterone, bovine serum albumin (BSA), cholesterol, uric acid, lactic acid, codein (COD), ascorbic acid, DHEA). Consequently, this work is proposed as practical, innovative and cost‐effective technique that can be easily adapted for the miniaturized form for the analysis of other doping substances as well as DHEA?S for the future works. 相似文献
30.
Gulsah Bor Ezgi Man Ozge Ugurlu Ayse Elcin Ceylan Simge Balaban Ceren Durmus Z. Pinar Gumus Serap Evran Suna Timur 《Electroanalysis》2020,32(9):1922-1929
Pesticide use in agriculture is one of the threats to water safety. Therefore, detection of pesticide residues is crucial for human health. Compared to conventional chromatographic methods, aptasensors are promising tools for fast, cheap and sensitive detection of environmental contaminants. To the best of our knowledge, such an aptasensor has not been reported for imidacloprid (Imi) which is one of the most widely used pesticides. In order to meet this demand, we initially selected two novel aptamers designated as ‘Apta‐1’ and ‘Apta‐2’ by graphene oxide‐SELEX (GO‐SELEX) method. Then, these aptamers were used to fabricate the gold electrode‐based aptasensor platforms and characterized by using electrochemical methods such as cyclic voltammetry, and electrochemical impedance spectroscopy as well as X‐Ray photoelectron spectroscopy. It was found that the limit of detection value of Apta‐1 based sensor for the Imi was found better than Apta‐2 based system, although linear ranges were similar. Based on that finding, Apta‐1 based system was further tested against possible interference molecules. The proposed platform was successfully used for detection of very low concentrations of Imi in the range of ng/mL. Thus, it eliminates the need for sample pre‐treatment and enables a practical analysis in real wastewater samples. 相似文献