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1.
The reaction of 1,1,1-tris(diiodarsinomethyl)ethane, CH3C(CH2AsI2)3 (I), with i-C3H7NH2, n-C4H9NH2, C6H5NH2, p-CH3C6H4NH2 and [(CH3)3Si]2NH in the presence of (C2H5)3N as auxiliary base in THF gives the adamantane cage compounds CH3C(CH2AsNC3H7)3 (III), CH3C(CH2AsNC4H9)3 (IV), CH3C(CH2AsNC6H5)3 (V), CH3C(CH2AsNC6H4CH3)3 (VI) and CH3C[CH2AsNSi(CH3)3]3 (VII). VII is also obtained in the reaction of I with NaN[Si(CH3)3]2. The by-product (CH3)3SiO(CH2)4I (VIII) could be isolated in both syntheses of VII. All compounds have been characterized by mass spectrometry and infrared, Raman and 1H NMR spectroscopy. 相似文献
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Hoang Dang Lanh G. Lietz Ho Si Thoang J. Völter 《Reaction Kinetics and Catalysis Letters》1982,21(4):429-432
The conversion of n-hexane was studied on a Pt-Sn/Al2O3 catalyst, a PtSn alloy and on the corresponding Pt catalysts. The results indicate the same catalytic effect of tin in supported and unsupported catalysts. It is concluded that the role of tin is connected with alloy formation.
- Pt-Sn/Al2O3, PtSn Pt-. . , .相似文献
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Christopher B. Lietz Qing Yu Lingjun Li 《Journal of the American Society for Mass Spectrometry》2014,25(12):2009-2019
Ion mobility (IM) is a gas-phase electrophoretic method that separates ions according to charge and ion-neutral collision cross-section (CCS). Herein, we attempt to apply a traveling wave (TW) IM polyalanine calibration method to shotgun proteomics and create a large peptide CCS database. Mass spectrometry methods that utilize IM, such as HDMSE, often use high transmission voltages for sensitive analysis. However, polyalanine calibration has only been demonstrated with low voltage transmission used to prevent gas-phase activation. If polyalanine ions change conformation under higher transmission voltages used for HDMSE, the calibration may no longer be valid. Thus, we aimed to characterize the accuracy of calibration and CCS measurement under high transmission voltages on a TW IM instrument using the polyalanine calibration method and found that the additional error was not significant. We also evaluated the potential error introduced by liquid chromatography (LC)-HDMSE analysis, and found it to be insignificant as well, validating the calibration method. Finally, we demonstrated the utility of building a large-population peptide CCS database by investigating the effects of terminal lysine position, via LysC or LysN digestion, on the formation of two structural sub-families formed by triply charged ions.
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Surface Chemistry, Sintering, and Redispersion of Pd/Al2O3 Catalysts Surface chemistry of Pd/Al2O3 has been investigated by temperature-programmed reduction, O2 chemisorption, and u.v.-vis spectroscopy. Depending on conditions of different thermal pretreatments especially in O2, different chlorine-free and chlorine-containing Pd compounds exist on the alumina. Sintering and redispersion of Pd are governed by properties of chlorine-free Pd oxide. The mechanism of Pd sintering consists in the thermal decomposition of a two-dimensional PdO phase; redispersion consists in formation of this phase by spreading of bulk PdO. There is no direct connection between Pd oxidation and redispersion. The discussion compares properties of Pd/Al2O3 and Pt/Al2O3. 相似文献
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Chiral, enantiomerically pure organic-soluble acids are often used as NMR chiral solvating agents (CSAs) for analyzing the enantiopurity of amines. However, the reports that describe CSAs for amines provide limited comparisons to other previously reported reagents. As such, it is difficult to know which among the many CSAs to pick when studying a new amine. We report a comparison of thirteen commercially available CSAs for the analysis of primary, secondary and tertiary amines in chloroform-d. (R)-α-methoxyphenylacetic acid, (R)-(-)-O-acetylmandelic acid, (R)-2-methoxy-2-(1-naphthyl)propionic acid and (R)-(-)-1,1′-binaphthyl-2,2′-diylhydrogenphosphate are identified as the best four to use as a starting point for the analysis of a new amine. 相似文献
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Gustav Lietz 《Colloid and polymer science》1943,102(1):22-29
Zusammenfassung Es wird über Abbauversuche an technischen Knochenleimen berichtet und die desaggregierende bzw. hydrolytische Wirkung verschiedener
Abbaumethoden unter Ausschlu? der normalen sauren oder alkalischen Hydrolyse durch die messende Verfolgung wesentlicher Eigenschaften,
wie Viskosit?t, schutzkolloides Verhalten und spezielle textilistische Wirkungen, ermittelt. Zur Unterscheidung der mizellaren
Desaggregation von der echten Hydrolyse werden die Aminostickstoff-Bestimmungsmethoden nach S?rensen, Willst?tter-Waldschmidt-Leitz
und van Slyke herangezogen. Bei der Beobachtung des thermischen Abbaus durch bis zu 24 stündigem Kochen ergibt sich neben
der zu erwartenden Desaggregation auch eine deutlich feststellbare hydrolytische Spaltung, wie aus dem Ansteigen der Formolzahlen
hervorgeht. Es wird angenommen, da? die von der Fabrikation her bereits st?rker abgebauten Knochenleime der Thermolyse leichter
unterliegen als hochaggregierte native Pr?parate.
Die Verfolgung der Einwirkung proteolytischer Fermente auf. Knochenleime, besonders unter Bedingungen, die von den für die
einzelnen Fermente optimalen abweichen, führt im ganzen zu Ergebnissen, die den Erwartungen entsprechen. W?hrend Chymase ausschlie?lich
in geringem Ma?e desaggregierend wirkt, kann sowohl die peptische wie die tryptische Verdauung auch unter milden Bedingungen
(bei nicht optimalem pH) zu Ergebnissen führen, die im Sinne der Zielsetzung dieser Untersuchungen liegen. 相似文献
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O. Lietz 《Fresenius' Journal of Analytical Chemistry》1904,43(11):712-713
Ohne Zusammenfassung 相似文献