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121.
Nair VA Mustafa SM Mohler ML Fisher SJ Dalton JT Miller DD 《Tetrahedron letters》2004,45(51):9475-9477
A series of optically active nonsteroidal selective androgen receptor modulators with structures analogous to bicalutamide was prepared by replacing the trifluoromethyl group with iodine and the sulfonyl linker by oxygen. 相似文献
122.
Certain Cu(I) and Cu(II) salts are able to mediate the dimerization of arylboronic acids in DMF. They provide the corresponding symmetrical biaryls in moderate to very good yields. It is possible to run the reaction catalytically under an oxygen atmosphere without a significant loss of yields. 相似文献
123.
Mustafa Korkmaz Burak Ozbagci 《Proceedings of the American Mathematical Society》2001,129(5):1545-1549
There exists a (relatively minimal) genus Lefschetz fibration with only one singular fiber over a closed (Riemann) surface of genus iff and . The singular fiber can be chosen to be reducible or irreducible. Other results are that every Dehn twist on a closed surface of genus at least three is a product of two commutators and no Dehn twist on any closed surface is equal to a single commutator.
124.
The energy levels of neutral atoms supported by potential V (r) = -Zexp(-ar)/r (Yukawa potential) are studied, using both dimensional and dimensionless quantities, via a new analytical methodical proposal (devised to solve for nonexactly solvable Schrödinger equation). Using dimensionless quantities, by scaling the radial Hamiltonian through y = Zr and = /Z, we report that the scaled screening parameter is restricted to have values ranging from zero to less than 0.4. On the other hand, working with the scaled Hamiltonian enhances the accuracy and extremely speeds up the convergence of the energy eigenvalues. The energy levels of several new eligible scaled screening parameter values are also reported. 相似文献
125.
Haldun Oguz Erkan Tarhan Murat Korkmaz Ugur Yilmaz Mustafa A. Safak Munir Demirci Levent N. Ozluoglu 《Journal of voice》2007,21(2):203-210
OBJECTIVE: The aim of this study was to identify the effects of objective laryngopharyngeal reflux (LPR) on the acoustic parameters of patients by comparing their voice samples with that of control subjects. STUDY DESIGN: Prospective study in two tertiary reference hospitals. METHODS: 48 consecutive patients with symptoms related to LPR and 64 control subjects were included in the study. Suspected LPR patients underwent a 24-hour ambulatory pH monitoring, and 25 (52%) of them were shown to have objective LPR. Acoustical evaluation results of objective LPR patients were compared with that of symptomatic LPR patients and control subjects. RESULTS: All frequency perturbation values obtained from objective and symptomatic LPR patients were higher than the control subjects (P<0.01). Mean fundamental frequency, amplitude perturbation measures, and noise-to-harmonics ratio were not significantly different between groups. CONCLUSION: LPR patients have significantly different frequency perturbation values than control subjects. 相似文献
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128.
Judit E. Puskas Mustafa Y. Sen Joseph R. Kasper 《Journal of polymer science. Part A, Polymer chemistry》2008,46(9):3024-3028
This article reports our discovery that poly(ethylene glycol) (PEG) can quantitatively be functionalized by transesterification using Candida antarctica lipase B (Novozyme 435) as the catalyst. α‐ω telechelic PEG‐methacrylates and PEG‐acetates were successfully prepared using commercially available PEGs with both narrow and broad molecular weight distribution. 1H and 13C NMR together with MALDI‐TOF mass spectroscopy verified the expected structures. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3024–3028, 2008 相似文献
129.
Mustafa Y. Sen Judit E. Puskas David E. Dabney Chrys Wesdemiotis Christelle Absalon 《Journal of polymer science. Part A, Polymer chemistry》2010,48(16):3501-3506
A new two‐step synthesis of polyisobutylene (PIB) with precisely one thymine functionality per chain (PIB‐T) is reported. The primary hydroxyl‐functionalized PIB (PIB‐OH) precursor was prepared by direct functionalization via living carbocationic polymerization of isobutylene initiated by the α‐methylstyrene epoxide/TiCl4 system. Matrix assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐ToF MS) of a low molecular weight PIB‐OH precursor demonstrated the effectiveness of direct functionalization by this method. A PIB‐acrylate precursor (PIB‐Ac) was obtained from such a PIB‐OH, and the PIB‐T was subsequently prepared by Michael addition of thymine across the acrylate double bond. MALDI‐ToF MS of the products verified that all polymer chains carried precisely one thymine group. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3501–3506, 2010 相似文献
130.
Timur I. Abdullin Oksana V. Bondar Irina I. Nikitina Emil R. Bulatov Michail V. Morozov Albert Kh. Hilmutdinov Myakzyum Kh. Salakhov Mustafa ulha 《Bioelectrochemistry (Amsterdam, Netherlands)》2009,77(1):37-42
We studied the electrochemical properties of gold nanoparticles (GNPs) and their complexes with proteins using square-wave voltammetry. Effect of the nanoparticle size and detection procedure was explored upon the oxidation of GNPs on a glassy carbon electrode (GCE). For pre-characterized GNPs of 13, 35 and 78 nm diameter, the oxidation peak potential was + 0.98, + 1.03 and + 1.06 V vs. Ag/AgCl, respectively. The conjugation of GNPs with four different proteins was verified by UV–Vis spectroscopy and atomic force microscopy indicated the formation of protein shells around GNPs. This process hampered the oxidation of GNPs on bare GCE causing pronounced decrease in the current response by an average factor of 72. GCE modification with carbon nanotubes weakly influenced the sensitivity of GNP detection but resulted in a 14.5-fold signal increase averaged for all GNP–protein complexes. The acidic dissolution and electrodeposition of GNPs or their complexes adsorbed on GCE allowed superior signal amplification directly proportional to nanoparticle size. The results are useful for the optimization of voltammetric analysis of GNP–protein complexes and can be extended to the characterization of other metal nanostructures and their complexes with biological components. 相似文献