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71.
M. Procop A. Klein I. Rechenberg D. Krüger 《Analytical and bioanalytical chemistry》1997,358(1-2):358-360
An ion beam technique has been developed which allows the preparation of bevels from semiconducting heteroepitaxial structures
with smooth surfaces and very flat angles in the order of 0.1°. The bevels are used for AES depth profiling of heterostructures
by the line scan technique. Measured and calculated line scans from (Al,Ga)As/GaAs and SiGe/Si test structures are compared
to estimate the contributions of the electron escape depth and the ion beam mixing to the depth resolution.
Received: 21 August 1996 / Revised: 14 January 1997 / Accepted: 18 January 1997 相似文献
72.
Alexander Nickolaevich Kholodov 《Acta Appl Math》1990,19(1):1-54
We determine all orthogonal polynomials having Boas-Buck generating functions g(t)(xf(t)), where% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGceaqabeaacqqHOo% qwcaGGOaGaamiDaiaacMcacqGH9aqpruqqYLwySbacfaGaa8hiamaa% BeaaleaacaaIWaaabeaakiaadAeacaqGGaWaaSbaaSqaaiaabgdaae% qaaOGaaeikaiaadggacaGGSaGaa8hiaiaadshacaqGPaGaaeilaiaa% bccacaqGGaGaaeiiaiaadggacqGHGjsUcaaIWaGaaiilaiaa-bcacq% GHsislcaaIXaGaaiilaiaa-bcacqGHsislcaaIYaGaaiilaiablAci% ljaacUdaaeaacqqHOoqwcaGGOaGaamiDaiaacMcacqGH9aqpcaWFGa% WaaSraaSqaaiaaicdaaeqaaOGaamOraiaabccadaWgaaWcbaGaaeOm% aaqabaGccaGGOaWaaSqaaSqaaiaaigdaaeaacaaIZaaaaOGaaiilai% aa-bcadaWcbaWcbaGaaGOmaaqaaiaaiodaaaGccaGGSaGaa8hiaiaa% dshacaGGPaGaa8hiamaaBeaaleaacaaIWaaabeaakiaadAeacaqGGa% WaaSbaaSqaaiaabkdaaeqaaOGaaeikamaaleaaleaacaaIYaaabaGa% aG4maaaakiaacYcacaWFGaWaaSqaaSqaaiaaisdaaeaacaaIZaaaaO% Gaaiilaiaa-bcacaWG0bGaaiykaiaacYcacaWFGaWaaSraaSqaaiaa% icdaaeqaaOGaamOraiaabccadaWgaaWcbaGaaeOmaaqabaGccaGGOa% WaaSqaaSqaaiaaisdaaeaacaaIZaaaaOGaaiilaiaa-bcadaWcbaWc% baGaaGynaaqaaiaaiodaaaGccaGGSaGaa8hiaiaadshacaGGPaGaai% 4oaaqaaiabfI6azjaacIcacaWG0bGaaiykaiabg2da9iaa-bcadaWg% baWcbaGaaGimaaqabaGccaWGgbGaaeiiamaaBaaaleaacaqGZaaabe% aakiaacIcadaWcbaWcbaGaaGymaaqaaiaaisdaaaGccaGGSaGaa8hi% amaaleaaleaacaaIYaaabaGaaGinaaaakiaacYcacaWFGaWaaSqaaS% qaaiaaiodaaeaacaaI0aaaaOGaaiilaiaa-bcacaWG0bGaaiykaiaa% -bcadaWgbaWcbaGaaGimaaqabaGccaWGgbGaaeiiamaaBaaaleaaca% qGZaaabeaakiaabIcadaWcbaWcbaGaaGOmaaqaaiaaisdaaaGccaGG% SaGaa8hiamaaleaaleaacaaIZaaabaGaaGinaaaakiaacYcacaWFGa% WaaSqaaSqaaiaaiwdaaeaacaaI0aaaaOGaaiilaiaa-bcacaWG0bGa% aiykaiaacYcaaeaadaWgbaWcbaGaaGimaaqabaGccaWGgbGaaeiiam% aaBaaaleaacaqGZaaabeaakiaacIcadaWcbaWcbaGaaG4maaqaaiaa% isdaaaGccaGGSaGaa8hiamaaleaaleaacaaI1aaabaGaaGinaaaaki% aacYcacaWFGaWaaSqaaSqaaiaaiAdaaeaacaaI0aaaaOGaaiilaiaa% -bcacaWG0bGaaiykaiaacYcacaGGUaGaa8hiamaaBeaaleaacaaIWa% aabeaakiaadAeacaqGGaWaaSbaaSqaaiaabodaaeqaaOGaaeikamaa% leaaleaacaaI1aaabaGaaGinaaaakiaacYcacaWFGaWaaSqaaSqaai% aaiAdaaeaacaaI0aaaaOGaaiilaiaa-bcadaWcbaWcbaGaaG4naaqa% aiaaisdaaaGccaGGSaGaa8hiaiaadshacaGGPaGaaiOlaaaaaa!C1F3!\[\begin{gathered}\Psi (t) = {}_0F{\text{ }}_{\text{1}} {\text{(}}a, t{\text{), }}a \ne 0, - 1, - 2, \ldots ; \hfill \\\Psi (t) = {}_0F{\text{ }}_{\text{2}} (\tfrac{1}{3}, \tfrac{2}{3}, t) {}_0F{\text{ }}_{\text{2}} {\text{(}}\tfrac{2}{3}, \tfrac{4}{3}, t), {}_0F{\text{ }}_{\text{2}} (\tfrac{4}{3}, \tfrac{5}{3}, t); \hfill \\\Psi (t) = {}_0F{\text{ }}_{\text{3}} (\tfrac{1}{4}, \tfrac{2}{4}, \tfrac{3}{4}, t) {}_0F{\text{ }}_{\text{3}} {\text{(}}\tfrac{2}{4}, \tfrac{3}{4}, \tfrac{5}{4}, t), \hfill \\{}_0F{\text{ }}_{\text{3}} (\tfrac{3}{4}, \tfrac{5}{4}, \tfrac{6}{4}, t),. {}_0F{\text{ }}_{\text{3}} {\text{(}}\tfrac{5}{4}, \tfrac{6}{4}, \tfrac{7}{4}, t). \hfill \\\end{gathered}\]We also determine all Sheffer polynomials which are orthogonal on the unit circle. The formula for the product of polynomials of the Boas-Buck type is obtained. 相似文献
73.
Weir AJ Klein SR Abrams G Adolphsen CE Akerlof C Alexander JP Alvarez M Amidei D Baden AR Ballam J Barish BC Barklow T Barnett BA Bartelt J Blockus D Bonvicini G Boyarski A Boyer J Brabson B Breakstone A Brom JM Bulos F Burchat PR Burke DL Butler F Calvino F Cence RJ Chapman J Cords D Coupal DP DeStaebler HC Dorfan DE Dorfan JM Drell PS Feldman GJ Fernandez E Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gidal G Gladney L Glanzman T Gold MS Goldhaber G Green A Grosse-Wiesmann P Haggerty J 《Physical review D: Particles and fields》1990,41(5):1384-1388
74.
Zhang X Sieval AB Hummelen JC Hessen B 《Chemical communications (Cambridge, England)》2005,(12):1616-1618
Polyethene with fullerene moieties pendant on short-chain branches was prepared by the catalytic copolymerization of ethene and a fullerene-containing vinylic comonomer, yielding polyethene copolymers containing up to 25 wt% of C60. 相似文献
75.
The near-infrared (NIR) absorption of toluene-sulfonate-diacetylene crystals (PTS) has been investigated during thermal polymerization. It is shown by comparative NIR and IR spectroscopy of deuterated and of protonated PTS at various temperatures, that these absorptions are vibronic in nature. They can be assigned unambiguously to distinct parts of the molecule. No low-lying electronic state has been found. 相似文献
76.
Vora A. Riga A. Dollimore D Alexander K. 《Journal of Thermal Analysis and Calorimetry》2004,75(3):709-717
This study attempts to identify the degradative process which folic acid undergoes in the solid-state under thermal stress.
In order to facilitate the process, the various pieces of the chemical structure, namely, p-amino benzoic acid, pterin and glutamic acid as both its d- and l-isomers were investigated as separate entities. These structured solid-state pieces were then compared to the composite solid
state folic acid degradative curves in order to identify the peaks seen and provide direction for the interpolation of the
degradative mechanism. It was observed that none of the structural pieces could be superimposed as assumed earlier and hence
an attempt was made to identify the decomposition products using various analytical techniques such as infrared spectroscopy,
mass spectroscopy and X-ray diffraction which suggested that the glutamic acid fragment is lost first as evidenced by acid
loss and amide enhancement in the IR spectra. The vitamin was ultimately degrading to carbon fragments and that further identification
was not necessary.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
77.
A. Hazra K. Alexander D. Dollimore A. Riga 《Journal of Thermal Analysis and Calorimetry》2004,75(1):317-330
The present study was aimed at determining the kinetics of evaporation and establishing vapor pressure curves for both single and multi-component systems by thermogravimetry (TG) and differential scanning calorimetry (DSC). Essential oils (e.g. lavender oil, orange oil, clove oil and eucalyptus oil, etc.) are typically multi-component systems consisting of various volatile pure components (e.g. linalyl acetate, limonene, cinnamaldehyde, etc.) which resemble single component systems. In this study linalyl acetate was taken as the calibration compound for TG. The vapor pressure curves for the pure substances were plotted using TG and vapor pressure plots for clove oil and eucalyptus oil were constructed using DSC. The thermodynamic and kinetic parameters of the pure compounds were compared to that of the multi-component systems to quantitatively and qualitatively measure the influence of different compounds on each other. The k-value from the vapor pressure data for linalyl acetate was calculated as 112006 Pa kg0.5mol0.5s-1 m-2 K-0.5. The vapor pressure values were used to determine the Antoine constants using the SPSS 10.0 software.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
78.
Ohne Zusammenfassung 相似文献
79.
Suman Dhami Garry Rumbles Alexander J. MacRobert David Phillips 《Photochemistry and photobiology》1997,65(1):85-90
Abstract— The photophysical properties of cis -disulfonated aluminum phthalocyanine (AlPcS2 ) in unilamellar vesicles (liposomes) of DL-a-dipalmitoyl-phosphatidylcholine have been measured. Both the fluorescence and triplet quantum yields decreased with increasing sensitizer concentration. The time-resolved fluorescence decays, analyzed by both the sum of exponentials and decay time distribution analyses, are compared with those reported for AlPcS2 in leukemic K562 cells. Information on the pho-todynamic transport and localization mechanism has been obtained by drawing correlations between the two systems, indicating active transport of the phthalocyanine into tumor cells involving lysosomal accumulation. 相似文献
80.