A5017410721- Microwave and Dielectric Measurement Techniques
- Advanced Electrical Measurement Techniques
- Sensor Technology and Measurement Systems
- Radio Frequency Integrated Circuit Design
- Corrosion Behavior and Inhibition
- Metal complexes synthesis and properties
- Microwave Engineering and Waveguides
- Inorganic and Organometallic Chemistry
- Synthesis and biological activity
- Synthesis of β-Lactam Compounds
- Scientific Measurement and Uncertainty Evaluation
- Synthesis and Characterization of Heterocyclic Compounds
- Concrete Corrosion and Durability
- Structural and Chemical Analysis of Organic and Inorganic Compounds
- Surface and Thin Film Phenomena
- Advanced Sensor Technologies Research
- Photochemistry and Electron Transfer Studies
- Electronic Packaging and Soldering Technologies
- Gyrotron and Vacuum Electronics Research
- Power Line Communications and Noise
- Carbohydrate Chemistry and Synthesis
- Synthesis and Biological Activity
- Particle accelerators and beam dynamics
- Hydrogen embrittlement and corrosion behaviors in metals
- Microwave-Assisted Synthesis and Applications
Eskişehir Osmangazi University
2009-2024
Tübitak National Metrology Institute
2002-2024
Scientific and Technological Research Council of Turkey
2011-2012
University of Maryland Extension
2000
Yeditepe University
1999
A novel series of cis-2-azetidinones 2(a-c ) was carried out by the cyclo addition reaction imine 1(a-c and acyl chloride in dry dichloromethane at 0-5 oC using triphenylamine. The Schiff bases with chloroacetyl resulted corresponding major product cis-2-azetidinone stereoisomers 2(a-c). synthesized compounds were characterized analytical spectral (Infrared, 1H NMR, 13C elemental analysis) data. Keywords: Benzothiazole, β-lactam, base, cis-2-azetidinone, Staudinger Acknowledgements authors...
Schiff base derivatives of benzothiazoles were synthesized using substituted 2-aminobenzothiazoles and different benzaldehydes. The structures the bases determined Fourier transform infrared spectroscopy, 1H NMR, 13C elemental analyses. acid dissociation behavior, which was visible in UV–visible absorption spectra, 10 novel benzothiazole studied. acidity constants (pKa), structures, protonation mechanisms studied molecules obtained. substituent effect on both phenyl rings these observed,...
The acid dissociation constants (K a ) of eight novel biologically active benzothiazole Schiff bases were determined by UV-vis spectroscopic technique at 25 ± 0.1 °C.The calculated acidity constants, pK values , evaluated in structure elucidation and protonation -deprotonation mechanisms.The prototropic tautomerism was also studied.
Radio Frequency (RF) power sensor calibration is one of the essential measurements in RF and microwave metrology. For a reliable accurate calibration, there are various methods, such as substitution method, direct comparison transfer method (DCTM), vector network analyzer (VNA)-based (VBCM). The VBCM that derived from DCTM. It preferred since VNA has better measurement capability fewer connection requirements for devices. In this study, milestones potential application errors given by...
Schiff base derivatives of benzothiazole 2a–e have been synthesized by reacting with substituted 2-aminobenzothiazole 1a–e and different benzaldehydes 5a–e. The obtained bases reaction NaBH4 has afforded the corresponding some novel amines 3a–e. condensation chloroacetylchloride leads to amide 4a–e. structures compounds are characterized elemental analysis, IR, MS, 1H NMR 13C NMR.
The aim of this paper is to compare the power measurement capabilities in millimetre- and sub-millimetre-wave frequency bands several national metrology institutes one research institute. first comparison, WR-6.5 waveguide (110 GHz 170 GHz), involved NPL, TUBITAK UME PTB. second WR-1.5 (500 750 METAS, UME, LNE, WAT, GUM VDI. Two types travelling standards were used for these comparisons: a thermoelectric sensor band calorimetric bands. was characterised by participants against their own...
The novel Schiff bases 3a?d were synthesized by reacting 6-methyl-2-aminobenzothiazole and different substituted benzaldehydes. Afterwards, the obtained reduced with NaBH4 to form amine compounds 4a?d. In final step, reaction of chloroacetyl chloride gave amide derivatives 5a?d. structures all characterized FT-IR, 1H-NMR, 13C-NMR, ESI MS, HETCOR, 2D (1H?1H) COSY spectra elemental analyses. antimicrobial activities compounds, tested against some Gram-positive Gram-negative bacterial as well...
2-Azetidinone (2b-e) and some unexpected azet-2(1H)-one derivatives (3b-f) were synthesized in two steps from the substitution of 2-aminobenzothiazole different substituted aromatic aldehydes.Firstly, Schiff bases prepared via reaction 2-aminobenzothiazoles with aldehydes.Second step was formation corresponding 2-azetidinone analogues by cyclocondensation chloroacetyl chloride phenoxy acetyl presence triethylamine.The chemical structures newly compounds confirmed FTIR, 1 H NMR, 13 C HMQC,...
In recent years, BNC type devices such as attenuator and termination are used for high frequency measurements. Unfortunately, there is no any primary standard to obtain traceability devices. It proposed N adapter characterization approach calibration standards, opens, shorts matched loads of Electrical delay calculated characterize then it measurement standards. To validate approach, known standards measured compared with actual results. Obtained results show good agreement. Difference...
Bilateral comparison of calibration factor microwave power sensor was carried out between National Metrology Institute Turkey (TÜBİTAK UME) and Measurement Calibration Center at Saudi Standards, Quality Organization the Kingdom Arabia (SASO NMCC). In this comparison, TÜBİTAK UME pilot laboratory supplied travelling standard with N type connector. Nine different frequency points 0 dBm level were determined for in prepared technical protocol. Each participant used their own measurement...
This paper describes the initial results of a characterisation study QHE samples performed at NMi Van Swinden Laboratorium end 1996. In this work, four different GaAs-based were studied currents and temperatures.
This paper describes measurement system established for microwave low power at TüBITAK UME. System was carried through the superheterodyne type receiver. The realized between 100 MHz to 26.5 GHz frequency range. Also error model of analyzed. output a signal source measured -60 dBm -120 dBm. expanded uncertainty (k=2) is 0.19 dB 3.04 in all
In response to the need for a reliable electrical connection between microwave cavity resonator be operated at temperatures as high 800 K and network analyzer room temperature, we designed suitable transmission lines. The performance of these lines was tested by measuring resonance frequency around 5 GHz cylindrical stainless steel ambient temperature 833 K.
This paper presents comparisons of the power measurement capabilities in millimetre and sub-millimetre-wave frequency bands several national metrology institutes one research institute. The first comparison is WR-6.5 waveguide (110 GHz to 170 GHz) second WR-1.5 (500 750 GHz). Two types travelling standard were used: a thermoelectric sensor (TPS) band calorimetric (CPS) band. TPS was characterised by participants against their own standards generalised effective efficiency calculated. CPS...
The new Schiff bases with D-?-A system were synthesized by the reaction of polycyclic aldehydes and substituted benzothiazoles. structures (7a 9a) determined FT-IR, 1H- -NMR, 13C-NMR, ESI-Mass elemental analyses. optical properties compounds investigated band gaps (Eg) calculated Tauc method using UV?Vis absorption spectra. Density functional theory (DFT/B3LYP/6-31G(d,p)) calculations conducted to get more insight on structural electronic novel bases. optimized molecular geometry,...
In this study, it is aimed to fabricate DC current shunt in the range from 1 A 10 with high accuracy and low drift. Resistance value of was chosen as mΩ which compatible national traceability chain. fabricated, characterized put into use at TÜBİTAK UME (National Metrology Institute Turkey) Laboratory.
This paper describes a bilateral comparison between two national metrology institutes, National Metrology Institute of Turkey (TÜBİTAK UME) and Measurement Calibration Center at Saudi Standards, Quality Organization the Kingdom Arabia (SASO NMCC). The aim is to check newly installed SASO NMCC radio frequency microwave laboratory infrastructure assess compatibility institutes. Measured quantity transmission coefficient fixed attenuators. was carried out in three months with 3 dB, 6 10 20 dB...
TUBİTAK UME has established a new power sensor calibration setup incorporating monitor utilizing the direct comparison transfer method for frequencies up to 50 GHz. The system adds TÜBİTAK UME's existing capability measure sensors with type Nand 3.5 mm connectors. measurement was validated using certificate values of each working frequency range. Good agreement found between previous results and those obtained system.
In order to evaluate the agreement between Physikalisch-Technische Bundesanstalt (PTB, Germany) and Ulusal Metroloji Enstitüsü (TÜBTAK-UME, Turkey) establish a firm basis for traceability, bilateral comparison has been carried out using 1 Ω, 10 kΩ 100 MΩ resistors. Measurements obtained by PTB, based on their quantum Hall resistance standard (QHRS), differ from UME results 46 nΩ/Ω (standard uncertainty u = 0.19 µΩ/Ω) at Ω level, 3.0 (u 0.25 level. The resistors were compared both...