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排序方式: 共有164条查询结果,搜索用时 31 毫秒
41.
Mustafa Soylak Yunus Emre Unsal 《International journal of environmental analytical chemistry》2013,93(5):440-447
In this work, a solid phase extraction method has been developed using a column filled with double-walled carbon nanotubes (DWNT) for preconcentration-separation of gold(III) ions prior to their flame atomic absorption spectrometric determination. Gold(III) ions were quantitatively recovered on DWNT in 1.0?mol?L?1 HCl. The influences of the analytical conditions including eluent type, sample volume, etc. on the recoveries of gold(III) ions were examined. The effects of concomitant ions were also investigated. The detection limits for gold(III) based on 3σ was calculated as 1.5?µg?L?1. The procedure presented in this paper was applied to the gold content of a number of water, geological and anodic slime samples with successful results. 相似文献
42.
In this article, we describe the preparation of a new lactose biosensor based on electrode coating with β‐galactosidase and glucose oxidase immobilized gelatin. For this purpose, β‐galactosidase and glucose oxidase enzymes were immobilized onto gelatin by crosslinking with glutaraldehyde. Properties of the immobilized β‐galactosidase and glucose oxidase enzymes electrode have been studied. The effects of glutaraldehyde concentration, temperature and pH variations and reusability were among the subjects analyzed. Lactose biosensors were subjected to continuous repeated use in order to observe reusability and shelf life; where standard lactose and milk samples were used as substrate solutions. Continuous reuse experiments showed that most of the lactose biosensors activities were retained even after the 10th use in a period of 30 days. 相似文献
43.
A New and Convenient Synthesis of Amino‐phthalimide (1H‐Isoindole‐1,3(2H)‐dione) Derivatives and Their Photoluminescent Properties 下载免费PDF全文
A new and convenient synthesis for amino‐phthalimide (1H‐isoindole‐1,3(2H)‐dione) derivatives has been developed starting from an α,β‐unsaturated ketone. The ketones were reacted with amines to give aromatic amine products. This is the first time that substituted amine groups have been incorporated in aromatic rings. The mechanism of the product formation is rationalized by the 1,2‐addition of amines to ketones. All aromatic compounds exhibited high fluorescence properties at the blue‐green region. 相似文献
44.
Amir Reza Sadrolhosseini Mohd Maarof Moksin W. Mahmood Mat Yunus Zainal Abidin Talib Mahnaz M. Abdi 《Optical Review》2011,18(4):331-337
Copper corrosion is one of the important parameters used for evaluating the quality of biodiesel. In this work, a polypyrrole-chitosan
sensing layer was utilized for the detection of Cu2+ in biodiesel using the surface plasmon resonance technique. With the sensitivity of this sensor being about 0.1 ppm, different
corrosion levels could be recognized in samples that were classified as class 1a according to the standard copper strip test. 相似文献
45.
Mukund G. Kulkarni Ajit S. Borhade Yunus B. Shaikh Vijay B. Ningdale Sanjay W. Chavhan 《合成通讯》2013,43(3):423-433
A two-step iterative sequence of Wittig olefination followed by Claisen rearrangement resulted in 1,7-octadienes, which afforded the corresponding cyclohexene carbaldehydes upon ring-closing metathesis with Grubbs catalyst. 相似文献
46.
We synthesized 9,10-dioxatricyclo[6.2.2.01,6]dodeca-3,11-dien-6-yl hydroperoxide (7) and investigated for the first time its further chemical transformation with dimethylsulfide, NEt3, PPh3, and Co-TPP, respectively. A variety of stereospecifically oxygenated compounds were obtained from these reactions containing different functional groups such as alcohols, ketone, and epoxides. 相似文献
47.
Hakan Sert Yunus Yıldız Tugba Onal Okyay Bahdisen Gezer Zeynep Dasdelen Betül Sen Fatih Sen 《Journal of Cluster Science》2016,27(6):1953-1962
Addressed herein, monodisperse Vulcan carbon supported Pt nanoparticles (Mw-Pt NPs@VC) have been reproducibly synthesized using the microwave assisted method and their application for methylene blue (MB) removal from aqueous solutions was investigated through the adsorption mechanism. The prepared nanomaterials were characterized by X-ray diffraction, transmission electron microscopy, high resolution transmission electron microscopy and X-ray photoelectron spectroscopy. All results show that highly crystalline and colloidally stable nanoparticles have been formed and Mw-Pt NPs@VC were found to be one of the the most active catalyst. The results showed that the Mw-Pt NPs@VC nanoparticles had remarkable MB adsorption capacity of 271.15 mg/g. The equilibrium for MB adsorption was attained in ~55 min. Moreover, Mw-Pt NPs@VC is a reusable and promising material for MB removal since it preserves 95.6 % of its initial efficiency after six successive cycles of adsorption–desorption. 相似文献
48.
Çiftçi Gönül Yenilmez Şenkuytu Elif İncir Saadet Elif Eçik Esra Tanrıverdi Zorlu Yunus Ölçer Zehra Uludağ Yildiz 《Mikrochimica acta》2017,184(7):2307-2315
Microchimica Acta - This paper describes an amperometric method for studying DNA-drug candidate interactions. It uses an automatted electrochemical biosensor (MiSens®) based on real-time... 相似文献
49.
Isha A Yusof NA Ahmad M Suhendra D Yunus WM Zainal Z 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,67(5):1398-1402
Fatty hydroxamic acid (FHA) immobilized in polyvinyl chloride (PVC) has been studied as a sensor element of an optical fibre chemical sensor for V(V). By using this instrument, V(V) in solution has been determined in the log concentration range of 0-2.5 (i.e. 1.0-300 mg/L). The detection limit was 1.0 mg/L. The relative standard deviation (R.S.D.) of the method for the reproducibility study at V(V) concentration of 200 mg/L and 300 mg/L were calculated to be 2.9% and 2.0%, respectively. Interference from foreign ions was also studied at 1:1 mole ratio of V(V):foreign ions. It was found that, Fe(III) ion interfered most in the determination of vanadium(V). Excellent agreement with ICP-AES method was achieved when the proposed method was applied towards determination of V(V). 相似文献
50.
Enantiospecific Synthesis of (R)‐3‐Amino‐4‐(2,4,5‐trifluorophenyl)butanoic Acid Using (S)‐Serine as a Chiral Pool 下载免费PDF全文
Aytekin Köse Özlem Gündoğdu Derya Aktaş Meryem Fıstıkçı Ramazan Altundaş Hasan Seçen Yunus Kara 《Helvetica chimica acta》2015,98(2):260-266
Starting from (S)‐serine, a new method was developed for the synthesis of the β‐amino acid part of sitagliptin in ten steps and with an overall yield of 30%. The crucial step of the synthesis was the ring opening of N‐ and O‐protected (R)‐aziridin‐2‐methanol with (2,4,5‐trifluorophenyl)magnesium bromide to give N‐ and O‐protected (R)‐2‐amino‐3‐(2,4,5‐trifluorophenyl)propan‐1‐ol. 相似文献