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1.
Gamini Gunawardena Derek Pletcher Anjam Razaq 《Journal of Electroanalytical Chemistry》1984,164(2):363-367
Cyclic voltammetry and potential step techniques have been used to study the electrodeposition of indium metal from 1 mol dm?3 potassium chloride, pH 2–4.5, onto a vitreous carbon electrode. It is confirmed that the In/In3+ couple is fast in chloride media and the nucleation and growth of the indium phase is discussed. It is shown that instantaneous nucleation occurs at an overpotential of only a few mV and that the growth of the nuclei is three dimensional. 相似文献
2.
Simultaneous detection of ultraviolet and infrared radiation in a single GaN/GaAlN heterojunction 总被引:1,自引:0,他引:1
Jayasinghe RC Ariyawansa G Dietz N Perera AG Matsik SG Yu HB Ferguson IT Bezinger A Laframboise SR Buchanan M Liu HC 《Optics letters》2008,33(21):2422-2424
Results are presented for a dual-band detector that simultaneously detects UV radiation in the 250-360 nm and IR radiation in the 5-14 microm regions with near zero spectral cross talk. In this detector having separate UV- and IR-active regions with three contacts (one common contact for both regions) allows the separation of the UV and IR generated photocurrent components, identifying the relative strength of each component. This will be an important development in UV-IR dual-band applications such as fire-flame detection, solar astronomy, and military sensing, eliminating the difficulties of employing several individual detectors with separate electronics-cooling mechanisms. 相似文献
3.
Mieszawska AJ Jalilian R Sumanasekera GU Zamborini FP 《Journal of the American Chemical Society》2005,127(31):10822-10823
This contribution describes the synthesis of gold nanorod (Au NR)/single-wall carbon nanotube (SWCNT) heterojunctions assembled directly on Si/SiOx substrates. SWCNTs are attached to amine-functionalized Si/SiOx substrates, and Au monolayer-protected clusters (MPCs) are adsorbed to the surface of SWCNTs through hydrophobic interactions. Seed-mediated reduction of HAuCl4 with ascorbic acid in the presence of cetyltrimethylammonium bromide (CTAB) onto the Au MPCs leads to the growth of larger Au nanostructures directly on the SWCNTs. Au NRs account for 19% of the nanostructures, some of which are attached directly to the sidewall and some at the ends of the SWCNTs. Raman spectroscopic measurements of SWCNTs before and after growth of the Au nanostructures reveal that the presence of Au leads to an approximately 50-fold enhancement of the Raman scattering signal. Combining 1D nanostructures of different materials (Au and carbon in this example) is of fundamental interest and may find use in nanoelectronics, chemical sensing, electrochemical, and spectroscopy applications. 相似文献
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Two new trioxygenated D:A-friedo-oleananes from Elaeodendron glaucum have been shown to be the angular methyl dioxygenated 25,28-dihydroxy-D:A-friedo-oleanan-3-one(1) and 3,28-dioxo-D:A-friedo-oleanan-25-ol(2) by interconversion and deoxygenation of the alcohol(2) using Lithium-ethyle diamine reduction coupled with spectroscopic methods. 相似文献
6.
In large LPs it may be that a major fraction of the constraints has a particularly simple form. Frequently this simple form may be exploited by either decomposition or implicit representation methods. In these cases, the effective size and computational difficulty are more closely related to the number of remaining nonspecial constraints than to the number of special constraints. A unified computational procedure is presented for mechanically identifying near maximal sets of special structure constraints for most of the kinds of special structures which have been identified thus far as being exploitable. 相似文献
7.
James E. Sealey Charles E. Frazier Gamini Samaranayake Wolfgang G. Glasser 《Journal of Polymer Science.Polymer Physics》2000,38(3):486-494
Esters of cellulose with trifluoroethoxy acetic acid (TFAA) were prepared in homogeneous phase using a mixed anhydride with p‐toluenesulfonic acid. Esters with low degree of substitution (DS), and with DS rising from 0 to 3, had hydrophobic character that prevented the usual association with moisture, which is otherwise typical of cellulose esters with low DS. Cellulose trifluoroethoxy acetate (CT) had Tg's declining by about 40 °C per DS‐unit (from 160 to 41 °C) as DS rose from 1 to 3. Mixed esters, cellulose derivatives with acetate and trifluoroethoxy acetate substituents (CAT), exhibited glass‐to‐rubber and melting transitions by DSC. A linear relationship between both Tg and Tm with respect to DS was recorded with the Tg and Tm separated by 30° to 40 °C. This is consistent with cellulose esters described elsewhere. Surprisingly, the Tg's of CT and CAT were found to be identical when the DS was equivalent to the DS of the fluoro substituents (DSF). © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 486–494, 2000 相似文献
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Gamini Gunawardane 《International Journal of Mathematical Education in Science & Technology》2013,44(1):149-150
In a recent issue of this journal, Trypia presented a simple rule to determine the blending pattern and quantities for a multi‐product blending firm. This paper presents three variations of Trypia's model suitable for discussion in production management and mathematical modelling courses. First, it presents a generalized version of Trypia's problem leading to a linear programming formulation. Next a more realistic version of Trypia's problem including set‐up costs is presented together with a simple method for determining production sequence and quantities. Finally, the case of sequence dependent set‐up costs is discussed. 相似文献
10.
Summary. Gibbs energy of transfer data for LiF and NaF from water to aqueous alcohol mixtures, obtained from solubility measurements, are
examined via the Born equation. In spite of its well-known deficiencies, the simple Born model accounts for much of the observed variation of Δt
G°(MF, w→w+ROH), particularly for NaF. This unexpected success of the Born model appears to result from the fortuitous cancellation of the donor and acceptor contributions to the solvation of the
cations and anions by these closely related co-solvents. Examination of the deviations between the observed and calculated
Δt
G° values also suggests that they are partly due to uncompensated ion-pairing effects, especially for LiF.
Corresponding author. E-mail: hefter@chem.murdoch.edu.au
Received October 29, 2002; accepted November 8, 2002
Published online April 24, 2003
RID="a"
ID="a"Dedicated to Prof. Dr. Heinz Gamsj?ger on the occasion of his 70th birthday 相似文献