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611.
612.
Ogawa M Sheverdyaeva PM Moras P Topwal D Harasawa A Kobayashi K Carbone C Matsuda I 《J Phys Condens Matter》2012,24(11):115501
Angle-resolved photoemission spectroscopy experiments show that the electronic structure of a Ag(111) film grown on Si(111) is markedly perturbed by the formation of a √3 × √3-Ag(2)Bi Rashba-type surface alloy. Four spin-split surface states, with different band dispersions and energy contours, intercept and hybridize selectively with the sp-derived quantum well states of the Ag layer. Detailed two-dimensional band mapping of the system was carried out and constant energy contours at different energies result in hexagonal-, star- and flower-like distortions of the quantum well states as a result of various interactions. Further wavy-like modulations of the electronic structure of the film are found to originate from umklapp reflections of the Ag film states according to the surface periodicity. 相似文献
613.
Zhou Wang Jianlong Chen Dinesh Khurana Tsit-Yuen Lam 《Algebras and Representation Theory》2012,15(1):195-200
We show that in a ring of stable range 1, any (von Neumann) regular element is clean. Our main results also imply that any
unit-regular ring has idempotent stable range 1 (and is therefore clean), and that a semilocal ring has idempotent stable
range 1 if and only if it is semiperfect. 相似文献
614.
Chhetri DK Neubauer J Berry DA 《The Journal of the Acoustical Society of America》2012,131(2):1401-1412
The laryngeal neuromuscular mechanisms for modulating glottal posture and fundamental frequency are of interest in understanding normal laryngeal physiology and treating vocal pathology. The intrinsic laryngeal muscles in an in vivo canine model were electrically activated in a graded fashion to investigate their effects on onset frequency, phonation onset pressure, vocal fold strain, and glottal distance at the vocal processes. Muscle activation plots for these laryngeal parameters were evaluated for the interaction of following pairs of muscle activation conditions: (1) cricothyroid (CT) versus all laryngeal adductors (TA/LCA/IA), (2) CT versus LCA/IA, (3) CT versus thyroarytenoid (TA) and, (4) TA versus LCA/IA (LCA: lateral cricoarytenoid muscle, IA: interarytenoid). Increases in onset frequency and strain were primarily affected by CT activation. Onset pressure correlated with activation of all adductors in activation condition 1, but primarily with CT activation in conditions 2 and 3. TA and CT were antagonistic for strain. LCA/IA activation primarily closed the cartilaginous glottis while TA activation closed the mid-membranous glottis. 相似文献
615.
A simple interferometric polarimeter with an integrated calibration scheme is proposed for accurate and fast mapping of the state of polarization (SOP). Conventional single-shot polarimeters that detect the amplitude and phase of orthogonally polarized field components by interferometry using Fourier fringe analysis suffers from errors caused by the imperfect reference beam and ambiguity in the spatial carrier frequency in the fringe pattern. In the proposed system, the integrated calibration scheme eliminates those error sources and enables accurate measurement of SOP without prior knowledge of the reference beam and the spatial carrier frequency. 相似文献
616.
Synthesis of Polysubstituted Pyrazolo[3,4‐b]pyridine‐3‐Carbohydrazide and Pyrazolo[3,4‐d]pyridazine Derivatives 下载免费PDF全文
Dinesh C. Bhavsar Prashant S. Nikam Sachin A. Gangurde Raghunath B. Toche 《Journal of heterocyclic chemistry》2014,51(3):635-641
5‐Amino‐4‐formyl pyrazole carboxylate gave facile reactions with malononitrile, hydrazine, and ketones in the presence of piperidine furnished substituted pyrazolo[3,4‐b]pyridines and pyrazolo[3,4‐b]quinolones. The pyridazine sulfonamides were obtained by the reaction of 5‐chloro 4‐formyl pyrazole carboxylate with sulfonamide derivatives. 相似文献
617.
Mercuric Acetate Mediated Oxidative Cyclization of (2E, 4E)‐1‐(2‐Hydroxyphenyl)‐5‐phenylpenta‐2,4‐dien‐1‐ones: Synthesis of (Z)‐2‐((E)‐3‐Phenylallylidene)benzofuran‐3(2H)‐ones 下载免费PDF全文
(2E,4E)‐1‐(2‐Hydroxyphenyl)‐5‐phenylpenta‐2,4‐dien‐1‐ones 1a , 1b , 1c , 1d , 1e on oxidative cyclization with mercuric acetate in dimethylsulphoxide have provided (Z)‐2‐((E)‐3‐phenylallylidene)benzofuran‐3(2H)‐ones 2a , 2b , 2c , 2d , 2e in good yields. 相似文献
618.
Shetty Kalidas Bothra Dinesh Crawford Don L. Korus Roger A. 《Applied biochemistry and biotechnology》1990,24(1):213-221
Applied Biochemistry and Biotechnology - Extracellular peroxidases were produced in plant cell suspension cultures in proportion to cell dry weight during exponential growth phase. This correlation... 相似文献
619.
Tectona grandis Linn (Teak), is locally known as Sagwan, belongs to Lamiaceae family. It is one of the most valuable timber in the world, due to its beautiful surface and its resistance to termite and fungal damage. The main active ingredient compounds that are responsible for these action are tectoquinone, lapachol and deoxylapachol. Naphthoquinones, anthraquinones and isoprenoid quinones are abundant metabolites in teak. In addition to these, teak contains several other phytochemicals such as triterpenoids, steroids, lignans, fatty esters and phenolic compounds. Pharmacologically, the plant has been investigated for antioxidant, anti-inflammatory, anti-pyretic, cytotoxic, analgesic, hypoglycemic, wound healing and antiplasmodial activities. The present review highlights the phytochemical and pharmacological aspects of teak. 相似文献
620.
Bhimareddy Dinesh Krishnayan Basuroy Narayanaswamy Shamala Padmanabhan Balaram 《Tetrahedron》2012,68(23):4374-4380
A cylindrical pore of ~7.5 Å diameter containing a one-dimensional water wire, within the confines of a hydrophobic channel lined with the valine side chain, has been observed in crystals of the peptide Boc–d-Pro-Aib-Val-Aib-Val–OMe (1) (Raghavender et al., 2009, 2010). The synthesis and structural characterization in crystals of three backbone homologated analogues Boc–d-Pro-Aib-β3(R)Val-Aib-Val–OMe (2), Boc–d-Pro-Aib-γ4(R)Val-Aib-Val–OMe (3), Boc–d-Pro-Aib-γ4(S)Val-Aib-Val–OMe (4) are described. Crystal structures of peptides 2, 3 and 4 reveal close-packed arrangements in which no pore was formed. In peptides 2 and 3 the N-terminus d-Pro-Aib segment adopted conformations closely related to Type II′ β-turns, while residues 2–4 form one turn of an αβ right-handed C11 helix in 2 and an αγ C12 helix in 3. In peptide 4, a continuous left-handed helical structure was observed with the d-Pro-Aib segment forming a Type III′ β-turn, followed by one turn of a left-handed αγ C12 helix. 相似文献