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81.
A novel bis scaffold containing a pentapeptide PHGGG, derived from the prion octarepeat, forms fibrils of nanometric dimensions, thus indicating that certain segments in the unstructured region of the prion protein may facilitate an initial fibrillation event. 相似文献
82.
Wavelength beam combining of five ytterbium fiber lasers is demonstrated in a master-oscillator power-amplifier configuration at combined powers up to 6 W. The combined beam profile has an M2 value of 1.14, which is equal to that of an individual fiber. Beam steering in one dimension over 140 resolvable spots is also demonstrated. 相似文献
83.
84.
We answer in negative a question of Gál and Miltersen [Proc 30th Int Coll Automata, Languages, and Programming (ICALP) 2003, pp. 332–344] about a combinatorial game arising in the study of time‐space trade‐offs for data structures. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2005 相似文献
85.
Rajendra N. Goyal Neena Jain Vibha Gurnani 《Monatshefte für Chemie / Chemical Monthly》2001,132(5):575-585
Summary. The electrochemical behaviour of chlorpromazine has been examined in phosphate buffers in aqueous as well as micellar media
at a pyrolytic graphite electrode surface. Two oxidation peaks were obtained in linear sweep voltammetry of chlorpromazine.
The first peak corresponds to the formation of the cationic free radical, which on further 1e−-oxidation gives a dication. The spectroscopic changes and kinetics of the cationic free radical and dication species generated
during electrooxidation of chlorpromazine were investigated in both media. The decay of the dication was studied chronoamperometrically
and was found to follow first-order kinetics with a half-life of ∼25 ms. Surfactants affect both E
p and i
p values. The anionic surfactant SDS has been found to catalyze the reaction of the free radical cation and the dication. 相似文献
86.
Here we investigate a majorization problem involving starlike function of complex order belonging to a certain class defined by means of fractional derivatives. Relevant connections of the main results obtained in this paper with those given by earlier workers on the subject are also pointed out. 相似文献
87.
88.
A. K. Goyal 《Periodica Mathematica Hungarica》1986,17(1):13-20
In this paper,D-strong and almostD-strong near-rings have been defined. It has been proved that ifR is aD-strongS-near ring, then prime ideals, strictly prime ideals and completely prime ideals coincide. Also ifR is aD-strong near-ring with identity, then every maximal right ideal becomes a maximal ideal and moreover every 2-primitive near-ring becomes a near-field. Several properties, chain conditions and structure theorems have also been discussed.Most of the parts of this paper are included in author's doctoral dissertation at Sukhadia University Udaipur (1983). The author expresses his gratitude to Dr.S. C. Choudhary for his kind guidance. 相似文献
89.
In this communication we present the synthesis and characterization of the first two members of a new class of metallomesogen. The Pd and Cu complexes of 1-hydroxy-2,3,5,6,7-pentakis(dodecyloxy)anthra-9,10-quinone were prepared by reacting the respective metal(II) acetate with the ligand. Preliminary mesophase characterization by DSC and polarizing optical microscopy indicates the formation of columnar mesophases in both the complexes. 相似文献
90.
Alan R. Katritzky Nabin K. Meher Sureyya Hanci Reena Gyanda Srinivasa R. Tala Sindhu Mathai Randolph S. Duran Sophie Bernard Firouzeh Sabri Sandeep K. Singh Jacek Doskocz David A. Ciaramitaro 《Journal of polymer science. Part A, Polymer chemistry》2008,46(1):238-256
Fourteen commercial polyols have been characterized by GPC, NMR spectroscopy, and elemental analysis. From these, eight corresponding tosylates, six nitrate esters, seven mesylates, 13 alkynes, and 14 azides have been prepared and all these derivatives have been fully characterized. Five alkyne monomers and eight azide monomers were also prepared. Twelve alkynes and 13 azides (functionality 2–4) were combined in 1,3‐dipolar cycloaddition reactions under neat conditions to prepare triazole‐cured polymers, avoiding any heavy metal catalyst. Characterization by NMR spectroscopy, elemental analysis, and gel permeation chromatography indicated triazole polymers 14 , 22 , 23 , 28 , and 30 with degrees of polymerization of 17–28 to be the best candidates for future work. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 238–256, 2008 相似文献