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81.
82.
Koh SE McDonald KD Holt DH Dulcey CS Chaney JA Pehrsson PE 《Langmuir : the ACS journal of surfaces and colloids》2006,22(14):6249-6255
The work function of indium tin oxide (ITO) substrates was modified with phosphonic acid molecular films. The ITO surfaces were treated prior to functionalization with a base cleaning procedure. The film growth and coverage were quantified by contact angle goniometry and XPS. Film orientation was determined by reflection/absorption infrared spectroscopy using ITO-on-Cr substrates. The absolute work functions of nitrophenyl- and cyanophenyl-phosphonic acid films in ITO were determined by Kelvin probe measurement to be 5.60 and 5.77 eV, respectively. 相似文献
83.
84.
This study examined the hypothesis that filamentous actin associated with the complex cytoskeleton of the kangaroo sperm head and tail may be contributing to lack of plasma membrane plasticity and a consequent loss of membrane integrity during cryopreservation. In the first study, the distribution of G and F actin within Eastern Grey Kangaroo (EGK, Macropus giganteus) cauda epididymidal spermatozoa was successfully detected using DNAse-FITC and a monoclonal F-actin antibody (ab205, Abcam), respectively. G-actin staining was most intense in the acrosome but was also observed with less intensity over the nucleus and mid-piece. F-actin was located in the sperm nucleus but was not discernable in the acrosome or sperm tail. To investigate whether cytochalasin D (a known F-actin depolymerising agent) was capable of improving the osmotic tolerance of EGK cauda epididymal spermatozoa, sperm were incubated in hypo-osmotic media (61 and 104 mOsm) containing a range of cytochalasin D concentrations (0-200 microM). Cytochalasin D had no beneficial effect on plasma membrane integrity of sperm incubated in hypo-osmotic media. However, when EGK cauda epididymidal sperm were incubated in isosmotic media, there was a progressive loss of sperm motility with increasing cytochalasin D concentration. The results of this study indicated that the F-actin distribution in cauda epididymidal spermatozoa of the EGK was surprisingly different from that of the Tammar Wallaby (M. eugenii) and that cytochalasin-D does not appear to improve the tolerance of EGK cauda epididymidal sperm to osmotically induced injury. 相似文献
85.
Visual information from a speaker's face profoundly influences auditory perception of speech. However, relatively little is known about the extent to which visual influences may depend on experience, and extent to which new sources of visual speech information can be incorporated in speech perception. In the current study, participants were trained on completely novel visual cues for phonetic categories. Participants learned to accurately identify phonetic categories based on novel visual cues. These newly-learned visual cues influenced identification responses to auditory speech stimuli, but not to the same extent as visual cues from a speaker's face. The novel methods and results of the current study raise theoretical questions about the nature of information integration in speech perception, and open up possibilities for further research on learning in multimodal perception, which may have applications in improving speech comprehension among the hearing-impaired. 相似文献
86.
We demonstrate that nearly critical quantum magnetic fluctuations in strongly correlated electron systems can change the Fermi surface topology and also lead to spin charge separation in two dimensions. To demonstrate these effects, we consider a small number of holes injected into the bilayer antiferromagnet. The system has a quantum critical point (QCP) which separates magnetically ordered and disordered phases. We demonstrate that in the physically interesting regime, there is a magnetically driven Lifshitz point (LP) inside the magnetically disordered phase. At the LP, the topology of the hole Fermi surface is changed. We also demonstrate that in this regime, the hole spin and charge necessarily separate when approaching the QCP. The considered model sheds light on generic problems concerning the physics of the cuprates. 相似文献
87.
Fomin N Arrington J Asaturyan R Benmokhtar F Boeglin W Bosted P Bruell A Bukhari MH Christy ME Chudakov E Clasie B Connell SH Dalton MM Daniel A Day DB Dutta D Ent R El Fassi L Fenker H Filippone BW Garrow K Gaskell D Hill C Holt RJ Horn T Jones MK Jourdan J Kalantarians N Keppel CE Kiselev D Kotulla M Lindgren R Lung AF Malace S Markowitz P McKee P Meekins DG Mkrtchyan H Navasardyan T Niculescu G Opper AK Perdrisat C Potterveld DH Punjabi V Qian X Reimer PE Roche J Rodriguez VM Rondon O 《Physical review letters》2012,108(9):092502
We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data also include the kinematic region where three-nucleon correlations are expected to dominate. 相似文献
88.
Satomi Niwayama Elizabeth M. Holt 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):e300-e301
The title compound, C12H16O6, prepared by a standard synthetic method, was determined by single‐crystal X‐ray crystallography to exist with a cyclopropane ring fused to a cyclopentene ring. Comparison of the unit‐cell dimensions and space group of this material with those of a crystal of the same material prepared using a route involving pig liver esterase hydrolysis shows them to be identical. 相似文献
89.
Sara K. Metcalf Elizabeth M. Holt 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):1228-1231
Diethyl 4‐(2,5‐dimethoxyphenyl)‐2,6‐dimethyl‐1,4‐dihydropyridine‐3,5‐dicarboxylate, C21H27NO6, (I), diethyl 4‐(3,4‐dimethoxyphenyl)‐2,6‐dimethyl‐1,4‐dihydropyridine‐3,5‐dicarboxylate, C21H27NO6, (II), and diethyl 2,6‐dimethyl‐4‐(3,4,5‐trimethoxyphenyl)‐1,4‐dihydropyridine‐3,5‐dicarboxylate, C22H29NO7, (III), crystallize with hydrogen‐bonding networks involving the H atom bonded to the N atom of the 1,4‐dihydropyridine ring and carbonyl O atoms in (I) and (II). Unusually, (III) shows O atoms of methoxy groups serving as hydrogen‐bond acceptors. 相似文献
90.
Aicha Benabad Karima Bakhous Fatima Cherkaoui Elizabeth M. Holt 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1292-1293
BiV0.4Fe3IIIO(PO4)3 crystallizes with two Fe atoms (one on an inversion centre and one on a mirror plane) displaying octahedral geometry and a third Fe atom (on a mirror plane) with trigonal bipyramidal coordination. Fe atoms are seen in oxygen‐bridged chains. BiV atoms are found in the interstitial sites between these chains. Bi shows sevenfold coordination, with Bi—O distances between 2.357 (7) and 2.529 (6) Å. 相似文献