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381.
Olkan Çuvalcı Faruk Ünker Turgut Batuhan Baturalp Utku Gülbulak Atila Ertaş 《声与振动》2021,55(4):281-294
In this paper, an experimental model of a horizontal cantilever beam with a rotating/oscillating attached to the shaker for harmonic excitation at the one end and a gyrostabilizer at the other end is built to verify the equations of the Lagrangian model. The primary focus of the study was to investigate the parameters of excitation amplitude, natural frequency, rotating mass (disk mass), and disk speed of gyro that would minimize the amplitude of the beam to identify these effects. Numerical and experimental results indicate that the angular momentum of the gyrostabilizer is the most effective parameter in the reduction of beam displacement. 相似文献
382.
Ümit H. Kaynar Mehmet Ayvacıklı Sermin Çam Kaynar Ümran Hiçsönmez 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(3):1469-1477
The adsorption of the uranyl ions from aqueous solutions on the nanoporous ZnO powders has been investigated under different experimental conditions. The adsorption of uranyl on nanoporous ZnO powders were examined as a function of the contact times, pH of the solution, concentration of uranium(VI) and temperature. The ability of this material to remove U(VI) from aqueous solution was followed by a series of Langmuir and Freunlinch adsorption isotherms. The adsorption percent and distribution coefficient for nanoporous ZnO powders were 98.65 % ± 1.05 and 7,304 mL g?1, respectively. The optimum conditions were found as at pH 5.0, contact time 1 h, at 1/5 Zn2+/urea ratio, 50 ppm U(VI) concentration and 303 K. The monomolecular adsorption capacity of nanoporous ZnO powders for U(VI) was found to be 1,111 mg g?1 at 303 K. Using the thermodynamic equilibrium constants obtained at different temperatures, various thermodynamic parameters, such as ΔG°, ΔH° and ΔS°, have been calculated. Thermodynamic parameters (ΔH° = 28.1 kJ mol ?1, ΔS° = 160.30 J mol?1 K?1, ΔG° = ?48.54 kJ mol?1) showed the endothermic and spontaneous of the process. The results suggested that nanoporous ZnO powders was suitable as sorbent material for recovery and adsorption of U(VI) ions from aqueous solutions. 相似文献
383.
A Potent,Selective and Cell‐Active Allosteric Inhibitor of Protein Arginine Methyltransferase 3 (PRMT3) 下载免费PDF全文
Dr. H. Ümit Kaniskan Dr. Magdalena M. Szewczyk Dr. Zhengtian Yu Dr. Mohammad S. Eram Dr. Xiaobao Yang Keith Schmidt Dr. Xiao Luo Miao Dai Dr. Feng He Irene Zang Dr. Ying Lin Dr. Steven Kennedy Dr. Fengling Li Elena Dobrovetsky Aiping Dong Dr. David Smil Dr. Sun‐Joon Min Dr. Melissa Landon Dr. Jennifer Lin‐Jones Dr. Xi‐Ping Huang Prof. Dr. Bryan L. Roth Prof. Dr. Matthieu Schapira Dr. Peter Atadja Dr. Dalia Barsyte‐Lovejoy Prof. Dr. Cheryl H. Arrowsmith Dr. Peter J. Brown Dr. Kehao Zhao Prof. Dr. Jian Jin Prof. Dr. Masoud Vedadi 《Angewandte Chemie (International ed. in English)》2015,54(17):5166-5170
PRMT3 catalyzes the asymmetric dimethylation of arginine residues of various proteins. It is essential for maturation of ribosomes, may have a role in lipogenesis, and is implicated in several diseases. A potent, selective, and cell‐active PRMT3 inhibitor would be a valuable tool for further investigating PRMT3 biology. Here we report the discovery of the first PRMT3 chemical probe, SGC707, by structure‐based optimization of the allosteric PRMT3 inhibitors we reported previously, and thorough characterization of this probe in biochemical, biophysical, and cellular assays. SGC707 is a potent PRMT3 inhibitor (IC50=31±2 nM , KD=53±2 nM ) with outstanding selectivity (selective against 31 other methyltransferases and more than 250 non‐epigenetic targets). The mechanism of action studies and crystal structure of the PRMT3‐SGC707 complex confirm the allosteric inhibition mode. Importantly, SGC707 engages PRMT3 and potently inhibits its methyltransferase activity in cells. It is also bioavailable and suitable for animal studies. This well‐characterized chemical probe is an excellent tool to further study the role of PRMT3 in health and disease. 相似文献
384.
Hüseyin Ünver Mustafa Yıldız Aşkın Kiraz Nazan Ocak İskeleli Ahmet Erdönmez Başaran Dülger Tahsin Nuri Durlu 《Journal of chemical crystallography》2006,36(3):229-237
A new Schiff base compound has been synthesized by the reaction of 2-hydroxy-1-naphthaldehyde with 3,5-bis(trifluoromethyl)aniline.The title compound was characterized by elemental analysis, IR,1H NMR,13C NMR, and UV–Visible techniques.Its UV–Vis spectra was examined in polar and nonpolar solvents and in acidic and basic media. The crystal structure of the compound showed the OH group to be ortho to the imine group. It crystallizes in the monoclinic space group P21 with a = 11.328(2), b = 6.125(1), c = 11.937(2) ?, V = 825.1(2) ?3, D
x
= 1.543 g cm−3and Z = 2. An intramolecular O1- H⋯N1 [2.558(7) ?] hydrogen bond stabilizes the molecule. The compound has also been characterized by its antimicrobial activities. The ligand has been screened in vitro against the organisms Escherichia coli ATCC 11230, Staphylococcus aureus ATCC 6538, Klebsiella pneumoniae UC57, Micrococcus luteus La 2971, Proteus vulgaris ATCC 8427, Pseudomonas aeruginosa ATCC 27853, Mycobacterium smegmatis CCM 2067, Bacillus cereus ATCC 7064, and Listeria monocytogenes ATCC 15313, the yeast cultures Candida albicans ATCC 10231, Kluyveromyces fragilis NRRL 2415, Rhodotorula rubra DSM 70403, Debaryomyces hansenii DSM 70238, and Hanseniaspora guilliermondii DSM 3432. 相似文献
385.
We describe the first usage of a double walled carbon nanotube (DWCNT) modified carbon paste electrode as biosensor transducer. Xanthine was chosen as a substrate for evaluation of the electrode performance. Proper amount of DWCNT and xanthine oxidase enzyme were mixed with proper amount of graphite and mineral oil for attaining the xanthine biosensor. Results were compared with previous work that includes multi-walled carbon nanotube and single-wall carbon nanotube based carbon paste electrode xanthine biosensors. A linearity was obtained in the concentration range between 2–50 μM xanthine under the response time of 150 s with the equation of y?=?0.0441x + 0.2013 and RSD value of 4.20%. This system was applied to the determination of xanthine in canned tuna fish samples and recovery was calculated as 99.20%?±?0.07. 相似文献
386.
A. Ülger 《Mathematische Zeitschrift》2006,254(4):715-728
In this paper we prove the Theorem: Let A be a Banach algebra with a bounded approximate identity (=BAI) such that every proper closed ideal of A is contained in a proper closed ideal with a BAI. Then a multiplier T:A → A has a closed range iff T factors as a product of an idempotent multiplier and an invertible multiplier.This work of the author is supported in part by the Turkish Academy of Sciences. 相似文献
387.
Hasan A. Aygör Serdar Ünlü Neçla Çakmak Cevat Selam 《Central European Journal of Physics》2014,12(7):490-498
Pyatov’s method has been applied to investigate Fermi beta transitions in deformed 74–80Kr isotopes. This self-consistent method, which was used to study the isobar analogue states in the spherical odd-odd nuclei, has to date not been applied for the isobar analogue states in deformed nuclei. The nucleon-nucleon residual interaction has been included so that the broken isospin symmetry in the mean field approximation has been restored and the strength parameter of the effective interaction has been taken out to be a free parameter. The energies and wave functions of the isobaric analogue excitations in 74–80Rb isotopes have been obtained within the framework of the pnQRPA method. The probability of the isospin mixing in the ground states and the centroid energies of the isobar analogue resonance have been presented and the deformation effects on these quantities have been quantified. 相似文献
388.
389.
390.
A mixture of bis‐benzimidazole salts ( 1–7 ), Pd(OAc)2 and K2CO3 in DMF ? H2O catalyzes, in high yield, the Suzuki and Heck cross‐coupling reactions assisted by microwave irradiation in a short time. In particular, the yields of the Heck and Suzuki reactions with aryl bromides were found to be nearly quantative. The synthesized bis‐benzimidazole salts ( 1 – 7 ) were identified by 1H? 13C NMR, IR spectroscopic methods and micro analysis. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献