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91.
Kumaranand Palaniappan Nadia Hundt Prakash Sista Hien Nguyen Jing Hao Mahesh P. Bhatt Yun‐Yue Han Elizabeth A. Schmiedel Elena E. Sheina Michael C. Biewer Mihaela C. Stefan 《Journal of polymer science. Part A, Polymer chemistry》2011,49(8):1802-1808
Poly(3‐hexylthiophene)‐b‐poly(4‐vinylpyridine) diblock copolymer was synthesized by RAFT polymerization of 4‐vinyl pyridine using a trithiocarbonate‐terminated poly(3‐hexylthiophene) macro‐RAFT agent. The optoelectronic properties and the morphology of the block copolymer blends with CdSe quantum dots were investigated. UV‐vis and fluorescence experiments were performed to prove the charge transfer between CdSe and poly(3‐hexylthiophene)‐b‐poly(4‐vinylpyridine) diblock copolymer. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
92.
Prakash Sista Mahesh P. Bhatt Ashton R. Mccary Hien Nguyen Jing Hao Michael C. Biewer Mihaela C. Stefan 《Journal of polymer science. Part A, Polymer chemistry》2011,49(10):2292-2302
Poly{4,8‐bis(4‐decylphenylethynyl)benzo[1,2‐b:4,5‐b′]dithiophene} ( P1 ) homopolymer and poly{4,8‐bis(4‐decylphenylethynyl)benzo[1,2‐b:4,5‐b′]dithiophene ‐alt‐thiophene} ( P2 ) alternating copolymer have been synthesized by Stille coupling polymerization. The field‐effect mobilities of both polymers were measured on both untreated and silane‐treated OFET devices. Various silanes were selected to allow an incremental increase in the hydrophobicity of the silicon dioxide dielectric. A direct correlation was observed between the hydrophobicity of the silicon dioxide dielectric surface and the enhancement of the field‐effect mobilities. The highest mobilities for both polymers were measured on the OFET devices treated with heptadecafluoro‐1,1,2,2‐tetrahydro‐decyl‐1‐trimethoxysilane (FS) which generated the most hydrophobic surface. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
93.
Mahesh M. SavantNeetha S. Gowda Akshay M. PansuriyaChirag V. Bhuva Naval KapuriyaSridhar M. Anandalwar Shashidhara J. PrasadAnamik Shah Yogesh T. Naliapara 《Tetrahedron letters》2011,52(2):254-257
A highly efficient strategy to 2,3-substituted chromen-4H-ones has been developed. The methodology involves unexpected intramolecular heteroannulation of readily accessible substituted 2-hydroxy-ω-nitroacetophenone with carbon disulfide in the presence K2CO3 followed by methylation with methyl iodide. These chromenones were further reacted with various nucleophiles such as amines, thiols, and alkoxide resulting in the facile C-N, C-S, and C-O bond formation. The scope and generality have been discussed. 相似文献
94.
95.
Mahesh S. Majik Perunninakulath S. Parameswaran Santosh G. Tilve 《Helvetica chimica acta》2008,91(8):1500-1504
A straightforward synthesis of (S)‐pyrrolam A is described. The synthesis involves in situ generation of the phosphorane 3 , followed by an intramolecular Wittig reaction to furnish (S)‐pyrrolam A. 相似文献
96.
Instantaneous phase shifting arrangement for microsurface profiling of flat surfaces 总被引:1,自引:0,他引:1
Phase shifting interferometry is a well-established technique for non-contact surface profile measurement. Though phase shifting technique has many advantages, it is marred by a few inaccuracies due to the vibration and mechanical movement of the phase shifter itself. Significant amount of work is reported to theoretically compensate these error sources. But for a few works, prominent achievements have not been reported in eliminating these error sources in phase shifting interferometry. In this paper, a novel optical layout, in combination with instantaneous phase shifting interferometry is described. Experiments were carried out with this setup on a super mirror with a λ/20 surface roughness, to demonstrate the validity of the principle. 相似文献
97.
Subhash P. Chavan Mahesh Thakkar Ashok B. Pathak Mohan M. Bhadbhade 《Tetrahedron》2005,61(15):3873-3879
The first enantiospecific synthesis of (+)-β-herbertenol, from naturally occurring R-(+)-citronellal, employing Taber's diazo decomposition protocol as the key step, is described. 相似文献
98.
Radhakrishnan Sivakumar Vijayaragavan Reena Nallamuthu Ananthi Muthiya Babu Sambandam Anandan Sivan Velmathi 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):1146-1151
Salicylaldimine based schiff base receptors with different substituents showing fluorescent enhancement in the presence of fluoride anion was visualized through naked eye as well as by change in spectral properties (UV–vis and fluorescent techniques). The reason for such fluorescence enhancement may be due to hydrogen bond interaction between receptor recognition site and fluoride anion. Such a hydrogen bond interaction creates a six-membered transition state, which avoids quenching processes. To support this, fluorescence enhancement factor (FEF) was calculated and it was found to be more (FEF = 652) for –NO2 substituted receptor compared to other receptors. 相似文献
99.
4S-Aminoproline polypeptide 2 forms unusual β-structure in trifluoroethanol that switches to the polyproline II (PPII) form in aqueous medium, while 4R-aminoproline peptide 1 retains PPII form in both solvents. This first instance of a polyproline derivative showing a β-structure is attributed to competitive pH-dependent (4-NH(3)(+)/NH(2)) stereoelectronic effect (4R vs 4S) and the overriding importance of stereospecific intra/intermolecular H-bonding in (2,4)-cis-4S-aminoproline in contrast to (2,4)-trans-4R-aminoproline oligomers. 相似文献
100.
Mahesh Chander Gupta 《Accreditation and quality assurance》2010,15(10):591-593
The ISO/IEC 17025 standard requires that all documents that form part of the management system of the organization must be
controlled. However, as customary, the certificates issued from testing or calibration laboratories do no bear any unique
identity mark/number similar to other documents to announce control over the document. This leaves enough room for doubt to
many in treating this document at par with other management system documentation. Some auditors had raised this question during
accreditation visits. 相似文献