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161.
Summary A technique is presented for the extraction of free and conjugated drugs and related compounds out of small quantities of urine. The method is designed in such a way that many samples can be tested for a great number of substances at the same time. Furthermore, we tried to achieve a high quality analysis using when ever possible chemicals with relatively low toxicity to men and environment. Therefore we avoided e.g., halogenated hydrocarbons. The detection of the substances is only performed by thin-layer chromatography (TLC) using well known reagents, like ninhydrin, Dragendorff, iodoplatinate and ferric chloride solutions. If necessary, the extracts can also be used with other Chromatographic techniques, particularly with GC/MS, if a substance has to be clearly identified. Approximately 500 authentical urines have been analyzed in a 1 year period using the method described. We found about 75 different substances. These results are presented in a table.  相似文献   
162.
Zusammenfassung Durch Einwirkung von SOCl2 auf 4-Hydroxycumarin bzw. 4-Hydroxycarbostyril sind Bis-(4-hydroxycumarinyl-[3])-sulfid (I) und Bis-(4-hydroxycarbostyril-[3])-sulfid (II) leicht zugänglich. Diese Sulfide können zu Dicumarino- bzw. Dicarbostyrilo-(1,4)-oxathiinen (III bzw. IV) cyclisiert werden.
Bis-(4-hydroxycoumarinyl-[3])-sulfide (I) and bis-(4-hydroxycarbostyril-[3])-sulfide (II) have been prepared by the reaction between SOCl2 and 4-hydroxycoumarin and 4-hydroxycarbostyril. Cyclisation of these sulfides yielded dicoumarino- (III) and dicarbostyrilo-oxathiin-(1.4) (IV).


Herrn KollegenH. Bretschneider, Innsbruck, mit den besten Wünschen zum 60. Geburtstag.

Aus der DissertationTh. Kappe, Universität Graz 1961, S. 78–83.  相似文献   
163.
Coulomb excitation of the first excited 2+-state was measured usingα-particles to determine reduced transition probabilities,B(E2; 0 gs + →2 1 + ), in nuclei with a closed shell of 82 neutrons. TheB(E2; 0 gs + →2 1 + -values are 10.2 single-particle units (spu) for138Ba, 13.5 spu for140Ce, 11.9 spu for142Nd and 11.6 spu for144Sm. The uncertainty ranges from 1.3 % to 2.3 %.  相似文献   
164.
High‐quality positron lifetime measurements (70 million total counts) are reported for polyethylenes (PEs) of different crystallinities (Xc = 3–82%). The specific volumes of the crystalline and amorphous phases (Vc and Va, respectively) were estimated from density and wide‐angle X‐ray scattering (WAXS) experiments. Some samples (those with low values of Xc) were branched PEs, and those with high values of Xc were linear PEs for which Xc was varied with changes in the crystallization temperature. Both Vc and Va increase with decreasing Xc in the range 0% ≤ Xc ≤ 56% (the branched PEs) but are constant for Xc ≥ 56% (the linear PEs). The lifetime spectra were analyzed with the MELT and LIFSPECFIT routines. Artifacts that can appear in the spectrum analysis were checked via an analysis of computer‐generated spectra. Four lifetime components appeared in all of the PEs; the two long‐lived ones are attributed to pick‐off annihilation of ortho‐positronium (o‐Ps) in crystalline regions (τ3) and in holes of the amorphous phase (τ4). With increasing Xc, τ3 decreases from about 1.2 to 1 ns, τ4 decreases from 3.0 to 2.5 ns, and the intensity I4 decreases from 29 to 0%. An increase in I3 from 6 to 12% was observed. A comparison with simulations shows that the true I3 value approaches 0 for Xc → 0%. The decrease in I4 is weaker than the increase in Xc; this leads to the conclusion that the apparent specific o‐Ps yield in the amorphous phase I4Xc increases with Xc. Possible reasons for this surprising results are discussed. The fractional free hole volume [h = (Va ? Vocc)/Va, where Vocc is the crystalline occupied volume] was estimated from density and WAXS results. Between Xc = 0 and 56%, h decreases from 0.151 to 0.090, but it does not change further above Xc = 56%. The mean size (v) of the local free volumes (holes) estimated from τ4 decreases from 200 to 150 Å3. The number density of holes (Nh) calculated from these values (Nh = h/v) also decreases from 0.8 to 0.6 nm?3 in the range 0% ≤ Xc ≤ 56%. The values of Va, Vc, h, and Nh increase with an increasing degree of branching but do not vary for linear PEs. The possible influence of a crystalline–amorphous interfacial phase (three‐phase model) on the observed lifetime parameters is also discussed. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 40: 65–81, 2002  相似文献   
165.
The coupling of liquid chromatography (l.c.) on narrow-bore columns to thin-layer chromatography (t.l.c.) is described. The effluent from a l.c. column can be deposited on a t.l.c. plate after a normal-phase or reversed-phase separation without serious loss of chromatographic information. Both silica and alkyl-modified silica plates can be used for storage. The interface is a fused silica capillary which connects the column outlet to the spray jet assembly of a Linomat applicator for t.l.c. The stored chromatogram can serve as starting point for a new separation, but also allows the use of detection principles which are normally not compatible with l.c. The chromatography of some polynuclear aromatic hydrocarbons is used to illustrate the possibilities of the combinations.  相似文献   
166.
Growth of Single Crystals of Ternary Rare Earth Vanadium(III) Oxides LnVO3 by Flux Electrolysis A simple method for growing single crystals of rare earth vanadium(III) oxides LnVO3 (Ln = La, Sm, Gd, Dy, Er, Yb) by cathodic reduction, starting from vanadium(V) oxide, in a flux of sodium tetraborate and sodium fluoride at T = 1000 K is described. The products were obtained as black, prismatic crystals, suitable for X-ray investigations etc. They were characterized by electron microprobe analyses and by X-ray powder investigations.  相似文献   
167.
Summary A two-dimensional, column liquid chromatographic system is used for the determination of the D- and L-enantiomers of amino acids in biological samples. Separation of the amino acids is first on ion-exchange column by gradient elution with a sodium citratesodium chloride buffer. Enantioseparation is by subsequent injection of 3 l heart-cuts of the individual amino acids onto a second column with a chiral crown ether stationary phase. Finally, fluorescence detection is after post-column labelling of the amino acids using ano-phthalaldehyde-2-mercaptoethanol reagent solution. The high separation power and selectivity of the system allow processing of complex samples with hardly any additional treatment and the determination of small quantities of D-amino acids in the presence of excess L-form. Applicability of the system is illustrated by the determination of D- and L-aspartate, serine, glutamate and alanine in various complex biological samples, such as protein hydrolysates, urine and biotechnological and food samples. Data are given on detectability, repeatability and linearity.  相似文献   
168.
Finehout EJ  Franck Z  Lee KH 《Electrophoresis》2004,25(15):2564-2575
We test the ability of state-of-the-art two-dimensional electrophoresis (2-DE) technology to enable the proteome mapping of ante mortem cerebrospinal fluid (CSF) from a single individual. Using the sensitive technologies of a fluorescent protein stain and fluorescence laser scanning of 2-DE gels, combined with matrix-assisted laser desorption/ionization-time of flight/time of flight-mass spectrometry (MALDI-TOF/TOF-MS) for protein identification, a highly detailed 2-DE map of the CSF proteome was created. The 2-DE map contains 600 identified spots representing 82 different proteins. Of the 82 proteins identified, 25 have not appeared in any previously published 2-DE map of CSF, and 11 have not been previously reported to exist in CSF. Most of the identifications originate from an ante mortem CSF sample collected from a single hydrocephalus patient. A supplemental map created from neurologically normal patients is also presented. A webpage with protein identification and scoring information from both maps is available at http://www.leelab.org/csfmap.  相似文献   
169.
Summary An on-line combination of liquid chromatography, gas chromatography and mass spectrometry has been realized by coupling a quadrupole mass spectrometer to an LC-GC apparatus. Liquid chromatography was used for sample pretreatment of oil samples of different origin. The appropriate LC fraction, containing polycyclic aromatic hydrocarbons, was transferred to the gas chromatograph using a loop-type interface. After solvent evaporation through the solvent vapour exit and subsequent GC separation, the compounds were introduced into the mass spectrometer for detection and identification. The GC column was connected to a short piece of deactivated fused silica that protruded into the ion source. The total analytical set-up allowed the direct analysis of oil samples after dilution in n-pentane without any sample clean-up. Detection limits are about 40 pg in the full scan mode and about 1 pg with selective ion monitoring, i.e. 20 ppb and 0.5 ppb respectively.  相似文献   
170.
All-cis cyclitols derived from cyclopentane have been prepared in two ways: (i) by LiAlH4 reduction of all-cis epoxypolyos; (ii) by dimethyl sulfoxide treatment, in the presence of sodium hydrogencarbonate, of brominated derivatives containing a neighbouring benzoyloxy group; under these conditions, the halogen is replaced by a cis-oriented hydroxyl group. Thus all-cis cyclopentane-tetrol and -pentol have been prepared; their configuration has been confirmed by NMR. spectroscopy.  相似文献   
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