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101.
Benjamin A. Chalmers Hui Xing Sevan Houston Charlotte Clark Sussan Ghassabian Andy Kuo Benjamin Cao Andrea Reitsma Cody‐Ellen P. Murray Jeanette E. Stok Glen M. Boyle Carly J. Pierce Stuart W. Littler David A. Winkler Paul V. Bernhardt Cielo Pasay James J. DeVoss James McCarthy Peter G. Parsons Gimme H. Walter Maree T. Smith Helen M. Cooper Susan K. Nilsson John Tsanaktsidis G. Paul Savage Craig M. Williams 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(11)
102.
Keefe CD Butler E Gillis E MacDonald JL 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,67(1):125-138
This paper reports the complex refractive index, molar absorption coefficient and imaginary molar polarizability spectra of liquid iodobenzene at 25 degrees C. The imaginary molar polarizability spectrum was fitted with 184 classical damped harmonic bands to determine the integrated intensity of the individual transitions. The standard deviation of the fitted spectrum from the experimental spectrum is 0.024 cm(3) mol(-1), and the R(2) value of the fit is 0.9968 indicating that the fitted spectrum is an accurate representation of the experimental spectrum. The dipole moment derivatives with respect to the normal coordinates and transition moments were determined for 26 of the 30 fundamentals. The total intensities of the in-plane and out-of-plane fundamentals were compared to benzene and other monosubstituted benzene derivatives using the F-sum rule. It was found that the total intensity of the out-of-plane fundamentals is essentially the same for the different compounds while the total intensities for the in-plane fundamentals varies according to the electronegativities of the substituents. 相似文献
103.
Beves JE Constable EC Housecroft CE Neuburger M Schaffner S Shardlow EJ 《Dalton transactions (Cambridge, England : 2003)》2007,(16):1593-1602
The reaction of 4'-(2-propyn-1-oxy)-2,2':6',2'-terpyridine (HC[triple bond]CCH2Oterpy) with trans-[PtI2(PR3)2] (R = Et, (n)Bu, Ph) results in the regioselective formation of the metalloditopic ligands trans-[Pt(C[triple bond]CCH2Oterpy)2(PR3)2], crystallographic data for which are presented. Each ditopic ligand reacts with FeCl(2).4H(2)O to give heterometallomacrocycles, the smallest of which is a [2 + 2] macrocycle, confirmed structurally for R = Et. The NMR spectroscopic data confirm the formation of symmetrical species, i.e. macrocyclic and not polymeric species. The distribution of products has been investigated using pulsed-field gradient spin-echo (PGSE) diffusion NMR spectroscopy, and indicates that the kinetic products from the reactions of 1, 2 or 3(L) with iron(II) are [Fe(n)L(n)](2n+) with n = 2, 3 or 4. For L = 1 and 2, these mixtures of products convert in solution to the thermodynamically favoured [Fe(2)L(2)](4+). 相似文献
104.
Laser-induced desorption of water molecules from nanometer amorphous solid water films supported on a single-crystal platinum substrate is reported. A femtosecond laser pulse creates hot substrate electrons, which are injected into the water layer, resulting in significant desorption at the water-vacuum interface. The dependence of the desorption yield on film thickness and results for isotopic spacer and capping layers reveal that the desorbing water originates from relatively deep down into the water layer, i.e., from several nanometers below the surface. This is proposed to be the result of cooperative electronic effects resulting from the high electron densities in the thin water film, which cause a transient destabilization of the water H-bonded network. Motion of excited water molecules through the layer is enabled by mixing within the layer on ultrafast timescales during the desorption process. 相似文献
105.
106.
An electrochemical synthetic condition is developed to produce cobalt hydroxide films with significantly increased basal spacings (d(001)>or= 25.0 A) by incorporating anionic surfactants (i.e. sodium dodecyl sulfate and 1-hexadecanesulfonate) into the interlayer regions via electrodeposition. 相似文献
107.
An electrochemical biosensor with a new bioorganometallic approach for the detection of human immunodeficiency virus (HIV) type 1 protease (HIV-1 PR) using surface-bound ferrocenoyl (Fc)-pepstatin conjugates is presented. 相似文献
108.
Competitive solubilization of cholesterol and phytosterols in nonionic microemulsions 总被引:1,自引:0,他引:1
It is well documented that phytosterols inhibit the uptake of exogenic cholesterol and do not interfere with cholesterol synthesis or cause side effects. The mechanism by which phytosterols interfere with cholesterol absorption is not completely clear and there are at least three hypotheses for their beneficial activity. Among these is that of competitive solubilization of phytosterols and cholesterol in dietary mixed micelles. In the present study we investigated the competitive solubilization of phytosterols (approximately 50% beta-sitosterol) and cholesterol in a nonionic microemulsion system constructed as a model for the dietary mixed micelles. We studied the effect of the competitive solubilization of cholesterol and phytosterols on the structural transformations and physical properties of the microemulsion and evaluated the locus of the solubilizates within the nanodroplets of each sterol separately and when they are loaded together at different weight ratios along one dilution line. Our results show that chemical and structural differences between cholesterol and phytosterols significantly influence the solubilization capacity of the nonionic microemulsion. Cholesterol, being more amphiphilic, is solubilized more efficiently at the W/O microemulsion interface, while in the O/W microemulsion phytosterols are dissolved somewhat more efficiently in the droplet core. 相似文献
109.
The gold(I)-catalyzed regioselective cyclizations of silyl ketene amides or carbamates with alkynes were utilized to construct cyclopentanes or dehydro-delta-lactams. 相似文献
110.
Perkell JS Denny M Lane H Guenther F Matthies ML Tiede M Vick J Zandipour M Burton E 《The Journal of the Acoustical Society of America》2007,121(1):505-518
The role of auditory feedback in speech production was investigated by examining speakers' phonemic contrasts produced under increases in the noise to signal ratio (N/S). Seven cochlear implant users and seven normal-hearing controls pronounced utterances containing the vowels /i/, /u/, /e/ and /ae/ and the sibilants /s/ and /I/ while hearing their speech mixed with noise at seven equally spaced levels between their thresholds of detection and discomfort. Speakers' average vowel duration and SPL generally rose with increasing N/S. Average vowel contrast was initially flat or rising; at higher N/S levels, it fell. A contrast increase is interpreted as reflecting speakers' attempts to maintain clarity under degraded acoustic transmission conditions. As N/S increased, speakers could detect the extent of their phonemic contrasts less effectively, and the competing influence of economy of effort led to contrast decrements. The sibilant contrast was more vulnerable to noise; it decreased over the entire range of increasing N/S for controls and was variable for implant users. The results are interpreted as reflecting the combined influences of a clarity constraint, economy of effort and the effect of masking on achieving auditory phonemic goals-with implant users less able to increase contrasts in noise than controls. 相似文献