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21.
M. Wunder und V. Thüringer 《Fresenius' Journal of Analytical Chemistry》1913,52(12):740-752
Ohne Zusammenfassung(Mitteilung aus dem Institut von Professor L. Duparc, Laboratorium für analytische Chemie der Universität Genf.) 相似文献
22.
M. Wunder und B. Jeanneret 《Fresenius' Journal of Analytical Chemistry》1913,52(2):99-101
Ohne Zusammenfassung 相似文献
23.
Justin Wunder 《Fresenius' Journal of Analytical Chemistry》1876,15(1):493
Ohne Zusammenfassung 相似文献
24.
25.
Toennes SW Schneider K Kauert GF Wunder C Moeller MR Theunissen EL Ramaekers JG 《Analytical and bioanalytical chemistry》2011,400(1):145-152
Cannabis is not only the most widely used illicit drug worldwide but is also regularly consumed along with ethanol. In previous
studies, it was assumed that cannabis users develop cross-tolerance to ethanol effects. The present study was designed to
compare the effects of ethanol in comparison to and in combination with a cannabis joint and investigate changes in pharmacokinetics.
In this study, 19 heavy cannabis users participated and received three alcohol dosing conditions that were calculated to achieve
steady blood alcohol concentrations (BAC) of about 0, 0.5 and 0.7 g/l during a 5-h time window. Subjects smoked a Δ9-tetrahydrocannabinol (THC) cigarette (400 μg/kg) 3 h post-onset of alcohol dosing. Blood samples were taken between 0 and
4 h after smoking. During the first hour, samples were collected every 15 min and every 30 min thereafter. Mean steady-state
BACs reached 0, 0.36 and 0.5 g/l. The apparent elimination half-life of THC was slightly prolonged (1.59 vs. 1.93 h, p < 0.05) and the concentration 1 h after smoking was slightly lower (24 vs. 17 ng/ml, p < 0.05) with the higher ethanol dose. The prolonged THC elimination might be explained by a small ethanol-mediated change
in distribution to and from deep compartments. Concentrations and pharmacokinetics of 11-hydroxy-THC and 11-nor-9-carboxy-THC
(THCA) were not significantly influenced by ethanol. However, THCA concentrations appeared lower in both ethanol conditions,
which might also be attributable to changes in distribution. Though not significant in the present study, this might be relevant
in the interpretation of cannabinoid concentrations in blood. 相似文献
26.
Johannes Schütz Wolfgang Brandt Mariana Spetea Klaus Wurst Gerhard Wunder Helmut Schmidhammer 《Helvetica chimica acta》2003,86(6):2142-2148
The novel morphinans 13 – 18 , which carry amino acid substituents at C(6), with potentially limited access to the central nervous system were prepared in two steps from 14‐O‐methyloxymorphone ( 5 ). Reductive amination with amino acid tert‐butyl esters gave compounds 7 – 12 , which were hydrolyzed with tetrafluoroboric acid. Structure elucidation (including X‐ray analysis), preliminary μ‐opioid receptor binding studies, and calculations of pharmacokinetic parameters were carried out. 相似文献
27.
Jingru Luo Yang Li Haochuan Zhang Ailun Wang Wei‐Shang Lo Qi Dong Nicholas Wong Christopher Povinelli Yucai Shao Sumanth Chereddy Stephanie Wunder Udayan Mohanty Chia‐Kuang Tsung Dunwei Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15457-15461
The incompatibility between the anode and the cathode chemistry limits the used of Mg as an anode. This issue may be addressed by separating the anolyte and the catholyte with a membrane that only allows for Mg2+ transport. Mg‐MOF‐74 thin films were used as the separator for this purpose. It was shown to meet the needs of low‐resistance, selective Mg2+ transport. The uniform MOF thin films supported on Au substrate with thicknesses down to ca. 202 nm showed an intrinsic resistance as low as 6.4 Ω cm2, with the normalized room‐temperature ionic conductivity of ca. 3.17×10?6 S cm?1. When synthesized directly onto a porous anodized aluminum oxide (AAO) support, the resulting films were used as a standalone membrane to permit stable, low‐overpotential Mg striping and plating for over 100 cycles at a current density of 0.05 mA cm?2. The film was effective in blocking solvent molecules and counterions from crossing over for extended period of time. 相似文献
28.
Abstract Numerical simulation of 18O exchange between CO2, H2O and HCO3 ? explains the ratio mass 46/mass 44 (=C18O16O/C16O2) measured by mass spectrometry to approximately 1% relative mean difference. In the presence of intact red blood cells the reaction takes place extra- and intracellularly at different reaction rates. Because CO2 hydration/dehydration is accelerated intracellularly by carbonic anhydrase, a difference in intra- and extracellular concentration of labelled reactants occurs. The ensuing transfer of reactants across the cell membrane depends on their membrane permeabilities which are approximately PCO 2 ? 2 cm/s, PH 2 O ? 0.002 cm/s and PHCO 3 ? 0.00015 cm/s (values from the literature). We found that the numerical simulation is affected most by PHCO 3 . The influence of the other permeabilities is at least ten times less. Therefore within the range of normal literature values, PHCO 3 is the only permeability that has a rate limiting effect on 18O exchange. This is why, in turn, PHCO 3 can be derived from an experimentally determined time course of mass 46/mass 44 by a fitting procedure. Another crucial parameter that can be estimated from the experimental results is the intraerythrocytic carbonic anhydrase activity Ai . 相似文献
29.
Parameswara Rao Chinnam Michael R. Gau Joseph Schwab Michael J. Zdilla Stephanie L. Wunder 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(10):971-974
Solvent‐free single crystals of 1,3,5,7,9,11,13,15‐octaphenylpentacyclo[9.5.1.13,9.15,15.17,13]octasiloxane (abbreviated as octaphenyl‐POSS), C48H40O12Si8, were obtained by dehydration/condensation of the tetrol Si4O4(Ph)4(OH)4. The powder pattern generated from the single‐crystal data matches well with the experimentally measured powder pattern of commercial octaphenyl‐POSS. The geometry of the centrosymmetric molecule in the crystal was compared with that in the gas phase, and had shorter Si—O bond lengths and a broader range of Si—O—Si bond angles. The average Si—O bond length [1.621 (3) Å], and Si—O—Si and O—Si—O bond angles [149 (5) and 109 (1)°, respectively] were within the same range measured previously for octaphenyl‐POSS solvates. 相似文献
30.
Jiang Ding Prithwiraj Maitra Stephanie L. Wunder 《Journal of Polymer Science.Polymer Physics》2003,41(17):1978-1993
Poly(ethylene oxide) (PEO) of 4600 molar mass (PEO‐4600) was crystallized from methanol in the presence of hydrophilic fumed silicas (A380, A200, and OX50) with nominal surface areas of 380, 200, and 50 m2/g and a hydrophobic fumed silica (R812s) modified with methyl groups. The composites were characterized by thermogravimetric analysis and differential scanning calorimetry. The inhibition of crystallization and the tendency for chain reorganization after melting were in the order of A380 > A200 > OX50 > R812s, respectively, that is, both were least for the hydrophobic silica and increased with increasing specific surface area for the hydrophilic silica. The interaction of PEO with the silica increased in the melt state as compared with the solution‐cast samples, resulting in enhanced suppression of crystallization. The following took place at a high silica content: (1) crystallization occurred at crystallization temperatures [Tc < Tc (bulk)], suggesting that the silica inhibited crystallization; (2) crystallites with melt temperatures [Tm < Tm (bulk)] were observed, indictive of smaller and/or less perfect crystals; and (3) melt entropies [ΔSm (surface) < ΔSm (bulk)] suggested that the interaction of surface silanols, SisOH, with PEO decreased both the melt entropy and crystallite size/perfection. Crystallinity was observed in solution‐cast composites when there were greater than ~0.03 PEO molecules/nm2 for native and ~0.01 PEO molecules/nm2 for methylated fumed silica, similar to reported plateau equilibrium adsorption values from methanol. These results were consistent with a model in which PEO interacted more strongly with native fumed silica as compared with hydrophobically modified silica because of hydrogen bonding of the ether oxygens of PEO with the acidic silanols, preventing chain mobility and crystallization. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1978–1993, 2003 相似文献