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21.
A. Hinz J. S. Wells A. G. Maki 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1987,5(4):351-358
Heterodyne frequency measurements are reported for absorption transitions of N2O in the frequency range from 1257 to 1335 cm?1. The measurements use a CO laser as a transfer oscillator whose frequency is measured directly against combinations of frequencies of two stabilized CO2 lasers whose frequencies are well known. A tunable diode laser is locked to the N2O absorption feature and the frequency difference is measured between the diode laser and the CO laser. Thev 3 fundamental bands of the15N14N16O and14N15N16O isotopes are reported. Measurements are also given for the 0002–0001, 0201–0200, and 0221–0220 vibrational transitions of N2O. A table of frequencies is given for the 0002–0000 band near 2560 cm?1 based on these and earlier measurements. 相似文献
22.
Jürgen G. Hinz 《Monatshefte für Mathematik》1983,95(4):275-286
Let ν denote a totally positive integer of an algebraic number fieldK such that ν is a least primitive root modulo a prime ideal \(\mathfrak{p}\) ofK, least in the sense that its normNν is minimal. One of the simplest questions that presents itself is that of the order of magnitude ofNν in comparison toN \(\mathfrak{p}\) . In the present paper the following bound is shown: $$N_\nu<< N\mathfrak{p}^{{1 \mathord{\left/ {\vphantom {1 4}} \right. \kern-\nulldelimiterspace} 4} + a} for fixed a > 0.$$ The proof of this result is based on deep estimates for certain character sums inK. 相似文献
23.
A new methodology based on pressurized liquid extraction (PLE) followed by LC-MS is presented for the simultaneous and unequivocal determination of alkylphenol ethoxylates (APEOs) and their degradation products, alkylphenols (APs) and alkylphenoxy carboxylates (APECs), in sediment samples. The protocol, applicable to a full range of APEO oligomers and degradation products, permits the sensitive and selective determination of APEOs (nEO = 1-15), APECs (nEO = 0-1) and APs at low ppb levels (LODs = 1-5 microg/kg) in sediment samples. Optimization of the operational parameters of PLE clearly demonstrates that significant thermal losses of APs occur during extraction at elevated temperatures. The loss of octylphenol (OP) at 100 degrees C was 61.2% and of nonylphenol (NP) 40.0%, whereas other compounds were completely recovered. Thus, to avoid losses due to the volatility of alkylphenols, a low extraction temperature should be applied. The conditions that gave the best results for all target compounds were as follows: extraction solvent mixture, methanol-acetone (1:1, v/v); temperature, 50 degrees C; pressure, 1500 p.s.i.; two static cycles. Using PLE and a subsequent clean-up with solid-phase extraction (SPE), the simultaneous extraction of APEOs, APs and APECs from sediment samples was achieved yielding recoveries >70% and producing low MS background noise. The developed methodology was applied on a routine basis to the analysis of alkylphenolic compounds in sediment samples. APEOs and their persistent degradation products were detected in significant concentrations in sediments from Portuguese rivers, especially at sites situated in the proximity of industrial plants (mainly the textile industry). The total concentration of alkylphenolic compounds (APEOs+APs+APECs) ranged from 155 to 2400 microg/kg. Of all the alkylphenolic compounds, NP comprised 40 to 50% with concentrations up to 1172 microg/kg. 相似文献
24.
Herbert Schumann Sebastian Dechert Frank Girgsdies Bernd Heymer Markus Hummert Ji‐Young Hyeon Jens Kaufmann Stefan Schutte Sonja Wernik Birgit C. Wassermann 《无机化学与普通化学杂志》2006,632(2):251-263
Synthesis and Characterization of New Intramolecularly Nitrogen‐stabilized Organoaluminium‐ and Organogallium Alkoxides The intramolecularly nitrogen stabilized organoaluminium alkoxides [Me2Al{μ‐O(CH2)3NMe2}]2 ( 1a ), Me2AlOC6H2(CH2NMe2)3‐2,4,6 ( 2a ), [(S)‐Me2Al{μ‐OCH2CH(i‐Pr)NH‐i‐Pr}]2 ( 3a ) and [(S)‐Me2Al{μ‐OCH2CH(i‐Pr)NHCH2Ph}]2 ( 4 ) are formed by reacting equimolar amounts of AlMe3 and Me2N(CH2)3OH, C6H2[(CH2NMe2)3‐2,4,6]OH, (S)‐i‐PrNHCH(i‐Pr)CH2OH, or (S)‐PhCH2NHCH(i‐Pr)CH2OH, respectively. An excess of AlMe3 reacts with Me2N(CH2)2OH, Me2N(CH2)3OH, C6H2[(CH2NMe2)3‐2,4,6]OH, and (S)‐i‐PrNHCH(i‐Pr)CH2OH producing the “pick‐a‐back” complexes [Me2AlO(CH2)2NMe2](AlMe3) ( 5 ), [Me2AlO(CH2)3NMe2](AlMe3) ( 1b ), [Me2AlOC6H2(CH2NMe2)3‐2,4,6](AlMe3)2 ( 2b ), and [(S)‐Me2AlOCH2CH(i‐Pr)NH‐i‐Pr](AlMe3) ( 3b ), respectively. The mixed alkyl‐ or alkenylchloroaluminium alkoxides [Me(Cl)Al{μ‐O(CH2)2NMe2}]2 ( 6 ) and [{CH2=C(CH3)}(Cl)Al{μ‐O(CH2)2NMe2}]2 ( 8 ) are to obtain from Me2AlCl and Me2N(CH2)2OH and from [Cl2Al{μ‐O(CH2)2NMe2}]2 ( 7 ) and CH2=C(CH3)MgBr, respectively. The analogous dimethylgallium alkoxides [Me2Ga{μ‐O(CH2)3NMe2}]2 ( 9 ), [(S)‐Me2Ga{μ‐OCH2CH(i‐Pr)NH‐i‐Pr}]n ( 10 ), [(S)‐Me2Ga{μ‐OCH2CH(i‐Pr)NHCH2Ph}]n ( 11 ), [(S)‐Me2Ga{μ‐OCH2CH(i‐Pr)N(Me)CH2Ph}]n ( 12 ) and [(S)‐Me2Ga{μ‐OCH2(C4H7NHCH2Ph)}]n ( 13 ) result from the equimolar reactions of GaMe3 with the corresponding alcohols. The new compounds were characterized by elemental analyses, 1H‐, 13C‐ and 27Al‐NMR spectroscopy, and mass spectrometry. Additionally, the structures of 1a , 1b , 2a , 2b , 3a , 5 , 6 and 8 were determined by single crystal X‐ray diffraction. 相似文献
25.
Sonja Strah Branko Stanovnik Simona Goli
Grdadolnik 《Journal of heterocyclic chemistry》1997,34(1):263-267
Alkyl 2-(2-benzoyl-2-ethoxycarbonyl-1-ethenyl)amino-3-dimethylaminopropenoates 4a,b were prepared. They react with C-nucleophiles such a 2-pyridinylacetonitrile 5 and methyl-2-quinolinylacetate 8, cyclohexane-1,3-dione 10 and its derivatives 12 and 14, resorcinol derivative 16 , 2-naphtol 18, 2-pyranone derivatives 20 and 22, and 4-hydroxypyridin-2(1H)-one 24, to form substituted amino derivatives of quinolizine 6, benzo[c]quinolizine 9, tetrahydrobenzopyran-2-one 11, 13, 15 , naphto[2,1-b]pyran-3-one 19 , pyranopyranones 21, 23, and pyrano[3,2-c]pyridine 25. 相似文献
26.
Cheremina O Bachmakov I Neubert A Brune K Fromm MF Hinz B 《Biomedical chromatography : BMC》2005,19(10):777-782
Oxycodone (14-hydroxy-7,8-dihydrocodeinone) is a potent opioid receptor agonist. In the present study, a liquid-liquid extraction-based reversed-phase HPLC method with UV detection was validated and applied for the analysis of oxycodone and its major metabolite, noroxycodone, in human plasma. The analytes were separated using a mobile phase, consisting of acetonitrile and phosphate buffer (8:92, v/v) at a flow rate of 1 mL/min, and UV detection at 205 nm. The retention times for oxycodone, noroxycodone and codein (internal standard) were 14.7, 13.8 and 10.2 min, respectively. The validated quantitation range of the method was 2-100 ng/mL for oxycodone and 10-100 ng/mL for noroxycodone. The developed procedure was applied to assess the pharmacokinetics of oxycodone and its metabolite following administration of a single 20 mg oral dose of oxycodone hydrochloride to one healthy male volunteer. 相似文献
27.
Jürgen G. Hinz 《Monatshefte für Mathematik》1979,87(3):229-239
Let \(K = \mathbb{Q}(\sqrt d )\) be any quadratic number field with discriminantd. ζ K (s) denotes the Dedekind zeta-function. The purpose of this note is to prove the following asymptotic formula: $$\int\limits_0^T {|\zeta _K ({1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2} + it)|^2 dt = ({6 \mathord{\left/ {\vphantom {6 {\pi ^2 }}} \right. \kern-\nulldelimiterspace} {\pi ^2 }})} \prod\limits_{p/d} {(1 + {1 \mathord{\left/ {\vphantom {1 p}} \right. \kern-\nulldelimiterspace} p})^{ - 1} \cdot R_K^2 \cdot T \cdot \log ^2 T + O_\varepsilon \left\{ {\left| d \right|1 + \varepsilon \cdot T \cdot \log T} \right\},} $$ where the implied constant depends only on ε. HereR K, denotes the residue of ζ K (s) ats=1. 相似文献
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