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51.
The ligand containing the 4‐amino‐1‐benzyl piperidine group, N, N′‐(4‐amino‐1‐benzyl piperidine)‐glyoxime, (LH2) (1) was prepared from 4‐amino‐1‐benzyl piperidine with anti‐dichloroglyoxime at ? 15 °C in absolute Tetrahydrofuran (THF). In the trinuclear [Pd(L)2Ru2(phen)4](ClO4)2 (4) and [Pd(L)2Ru2(bpy)4](ClO4)2 (5) metal complexes, the PdII ion centered into the main oxime core by the coordination of the imino groups while the two RuII ions coordinated dianionic oxygen donors of the oxime groups and linked to the ligands of 1,10‐phenanthroline and 2,2′‐bipyridine. The mono and trinuclear metal complexes were characterized by elemental analyses, FT‐IR, UV–vis, 1H and 13C‐NMR spectra, magnetic susceptibility measurements, molar conductivity, cyclic voltammetry, mass spectra, X‐ray powder techniques and their morphology by SEM measurements. The cyclic voltammetric results show that the cathodic peak (Epc) potential of (3) shifts towards more positive values compared with that of (2) as a result of the BPh2+‐bridged complex formation. The Suzuki–Miyaura reaction was used to investigate their activity as catalyst either prepared in‐situ or from well‐defined complexes. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
52.
新疆大学大学生营养知识态度行为的调查 总被引:1,自引:0,他引:1
目的了解新疆大学大学生营养知识、膳食态度、膳食结构和行为现况及存在的问题,为今后开展营养教育的设计及干预提供科学依据.方法采用自行设计的营养知识等方面的问卷,对新疆大学在校的2859名不同生源地,一~三年级不同专业男、女大学生中进行营养知识,膳食态度与膳食结构和行为的抽样调查.结果学生营养知识方面42.4%学生合格,其中男生39%、女生45.8%,膳食态度方面合格率达到72.2%,其中男生62.1%、女生82.3%,膳食结构和行为合格率57.9%,其中男生51.6%、女生64.6%.结论多数学生缺乏必要的营养知识,学生正确营养态度形成率均不高,如:不吃早餐、吃零食等行为较普遍,早餐及各类食物营养价值的有关知识欠缺,膳食结构及行为存在严重的不合理性,尤以农村生源学生及二,三年级学生为重,但有较好的健康饮食意识,他们接受营养知识的态度较好,愿意接受更多的营养知识并改正不良的饮食习惯,应采取多种措施加强对大学生营养知识的宣传教育和营养健康教育,纠正不良饮食行为,引导养成合理膳食行为,尤其是对来自农村学生及女生中针对性的进行膳食营养健康教育及干预十分必要. 相似文献
53.
Electrochemical and optical properties of novel donor‐acceptor thiophene‐perylene‐thiophene polymers
Sermet Koyuncu Mahmut Kus Serafettin Demic İsmet Kaya Eyup Ozdemir Siddik Icli 《Journal of polymer science. Part A, Polymer chemistry》2008,46(6):1974-1989
In this study, donor‐acceptor type thiophene‐perylene‐thiophene monomers were synthesized and polymerized by both oxidative polymerization using FeCl3 as catalyst and the electrochemical process. UV–vis, FTIR, 1H NMR, and elemental analysis techniques were used for structural characterization. Thermal behaviors of these compounds were determined by using TGA system. The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels and electrochemical and optical band gap values were calculated by using the results of cyclic voltammetry and UV–vis measurements, respectively. The number–average molecular weight (Mn), weight–average molecular weight (Mw), and polydispersity index (PDI) values of synthesized polymers were determined by size exclusion chromatography. Conductivity measurements of these polymers were carried out by electrometer by using a four‐point probe technique. The conductivity was observed to be increased by iodine doping. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1974–1989, 2008 相似文献
54.
55.
Aytaç Gültekin Gamze Karanfil Faruk Özel Mahmut Kuş Ridvan Say Savaş Sönmezoğlu 《Journal of Physics and Chemistry of Solids》2014
In the present study, pure and gold nanoparticle (Au NP)-doped titanium dioxide (TiO2) and cadmium oxide (CdO) thin film were prepared by the sol–gel method, and the effect of Au NP doping on the optical, structural and morphological properties of these thin films was investigated. The prepared thin films were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet–visible–near infrared (UV–Vis–NIR) spectra. While the optical band increases from 3.62 to 3.73 for TiO2 thin films, it decreases from 2.20 to 1.55 for CdO thin films with increasing Au doping concentration. Analysis of XRD indicates that the intensities of peaks of the crystalline phase have increased with the increasing Au NP concentrations in all thin films. SEM images demonstrate that the surface morphologies of the samples were affected by the incorporation of Au NPs. Consequently, the most significant results of the present study are that the Au NPs can be used to modify the optical, structural and morphological properties of TiO2 and CdO thin films. 相似文献
56.
Mahmut Akyig̃it Hidayet Hüda Kösal Murat Tosun 《Advances in Applied Clifford Algebras》2014,24(3):631-641
In this paper, the Fibonacci generalized quaternions are introduced. We use the well-known identities related to the Fibonacci and Lucas numbers to obtain the relations regarding these quaternions. Furthermore, the Fibonacci generalized quaternions are classified by considering the special cases of quaternionic units. 相似文献
57.
Cumhur Canbazoğlu Mahmut Doğru 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1245-1249
Determining radioactivity levels in foodstuffs is of great importance for the protection of human health. In addition, the literature includes few studies related to this subject in Turkey. In this study, gamma spectroscopic system was used in order to measure 226Ra, 232Th, 40K and 137Cs activity concentrations in vegetables and fruits produced in Elaz?? Region. The average activity concentrations in vegetables was calculated as 0.64 ± 0.26 Bq kg?1 for 226Ra, 0.65 ± 0.14 Bq kg?1 for 232Th, 13.98 ± 1.22 Bq kg?1 for 40K, and 0.54 ± 0.04 Bq kg?1 for 137Cs. The average activity concentrations in fruits were 1.52 ± 0.34, 0.98 ± 0.23, 18.66 ± 1.13 and 0.59 ± 0.16 Bq kg?1, respectively for 226Ra, 232Th, 40K and 137Cs. Total committed effective dose value was determined as 20 and 30.55 μSv y?1, respectively for vegetables and fruits. The findings were compared with previous data reported for Turkey and other regions of the world. 相似文献
58.
Mahmut Erzengin Dudu Demir Mikail Arslan Selma Sinan 《Applied biochemistry and biotechnology》2014,173(7):1597-1606
Paraoxonase 1 (PON1: EC 3.1.8.1) is a calcium-dependent enzyme associated with high-density lipoproteins (HDLs) and has a protective effect against oxidation of low-density lipoproteins (LDLs) in mammals. PON1 is the best-studied member of a family of enzymes called serum paraoxonases, or PONs, identified in mammals and other vertebrates as well as in invertebrates. PONs exhibit a range of important activities, including drug metabolism and detoxification of organophosphates such as nerve agents. This study reports, for the first time, purification and biochemical characterization of serum PON1 from different bovine breeds namely Swiss Black, Holstein, and Montofon. Bovine serum PON1s were purified using ammonium sulfate precipitation followed by Sepharose-4B-l-tyrosine-1-naphthylamine hydrophobic interaction chromatography. SDS–polyacrylamide gel electrophoresis of the purified enzymes indicates a single band with an apparent MW of 43 kDa. The purified enzymes had a specific activity of 10.78, 27.00, and 22.38 U/mg for Swiss Black, Holstein, and Montofon bovines, respectively. The overall purification rates of our method were 262.47-, 2,476.90-, and 538.06-fold for Swiss Black, Holstein, and Montofon bovines, respectively. Furthermore, using phenyl acetate as a substrate, we determined the K M and V max values of the purified enzymes, as 0.80 mM, 1428.5 U/ml for Swiss Black; 0.40 mM, 714.3 U/ml for Holstein; and 0.50 mM, 1,111.1 U/ml for Montofon bovine. The present study has revealed that there is no substantial difference in PON1 activities among the studied bovine breeds. 相似文献
59.
我们采用标志重捕方法对废弃地小型兽类群落的物种组成及种群生态学特征进行了初步研究.结果表明,废弃地小型兽类群落由以下八个物种组成:共捕鼠类529只,分别是普通田鼠52只,小家鼠230只.中麝嗣103只,黑家鼠24只,褐家鼠96只,小林姬鼠15只,田鼠5只和Pygmy中麝嗣1只.根据活动区大小的分析发现各物种在废弃地具有各自的活动领域和微栖息地.各物种的种群密度,繁殖周期,迁移特征表明,它们在不同的样地之间进行交流.总的来说,废弃地为不同的小型兽类提供丰富的食物资源和繁殖活动场所,同时有利于小型兽类的隐蔽,减少捕食危险,因此该景观中的小型兽类物种多样性比较大,已形成比较稳定的鼠类群落. 相似文献
60.
Mahmut Torul Halil Hogren Giray Topal Mürüvvet Yurdako 《Journal of heterocyclic chemistry》2005,42(6):1201-1205
A new selective molecular receptor, borocryptate, based on the combination of the 15 membered ring diazatrioxa core and two saligenin units as binding sites for boron has been described. The resulting peristatic chiral compound is stable in air and easily converted to polynuclear complex, Na‐borocryptate, without using an inert atmosphere. 相似文献