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171.
A. Tönnißen J. Wanner K. W. Rothe H. Walther 《Applied Physics A: Materials Science & Processing》1979,18(3):297-304
The measurement of the concentration of gaseous hydrogen fluoride in the exhaust of an aluminum plant by resonance absorption
of the radiation of a cw chemical HF laser is reported. The HF concentration has been evaluated taking into account the simultaneous
absorption of water vapor and carbon dioxide at the HF laser frequencies. The absorption cross sections for H2O and CO2 at the HF laser lines have been determined in laboratory experiments. 相似文献
172.
Walther G.?JaryEmail author Thorsten?Ganglberger Peter?P?chlauer Heinz?Falk 《Monatshefte für Chemie / Chemical Monthly》2005,136(4):537-541
Summary. A novel chemical source of singlet oxygen based on the conversion of ozone by 1,1-bis(triphenylphosphino)ferrocene as catalyst was developed into a feasible method for a preperative scale. This is, to our best knowledge, the first application of substituted ferrocenes as oxidation catalysts. 相似文献
173.
Vitamin A and some of its isomers are separated and quantitatively determined as trimethylsilylethers by gas liquid chromatography. The identity of the different fractions is proved by mass spectrometry. 相似文献
174.
Known estimates of the maximal length of simple circuits in certain 3-connected planar graphs are surveyed and improved in several directions. 相似文献
175.
The microwave spectrum of the two possible O-monodeuterated species has been measured in a mixture containing roughly 25% of each of the four possible OH/OH, OH/OD, OD/OH, and OD/OD isotopic species. Both spectra follow a semirigid rotor model without effects due to the tunneling of the two hydroxyl protons. Only one conformer has been detected: one oxygen is gauche with respect to the other; one hydroxyl hydrogen participates in the hydrogen bond, while the second one is trans with respect to the C---C bond. Precise values for the quartic centrifugal distortion constants have been obtained for both species. A measure of the dipole moment is given. 相似文献
176.
177.
C.R. Ottermann G. Köbschall K. Maurer K. Röhrich Ch. Schmitt V.H. Walther 《Nuclear Physics A》1985,436(4):688-698
The cross sections for elastic electron scattering from 3He and 4He were measured for the momentum transfer range from 0.45–2.0 fm?1. The cross sections were separated into their longitudinal (charge) and transverse (magnetic) contributions using the Rosenbluth formula. The charge and magnetic form factors were obtained model-independently.The rms charge radii were found to be 1.671 (14) fm for 4He and 1.976 (15) fm for 3He, and the magnetic rms radius of 3He is 1.99 (6) fm. The mis charge radius for 4He is in excellent agreement with the latest muonic data.Comparison of the form factors was made with Faddeev three-body calculations using realistic two-body NN interactions. At present the theoretical calculation is not able to reproduce the experimental data. 相似文献
178.
In the last few years, the need to determine peroxide-based explosives in solid samples and air samples has resulted in the
development of a series of new analytical methods for triacetonetriperoxide (TATP, acetone peroxide) and hexamethylenetriperoxidediamine
(HMTD). In this review, after a short introduction describing the state of the art in the field, these new analytical methods
are critically discussed. Particular emphasis is placed on spectroscopic and mass spectrometric methods as well as on chromatographic
techniques with selective detection schemes. The potential of these methods to analyse unknown solid samples that might contain
one or more of the explosives and to analyse peroxide-based explosives in air is evaluated. 相似文献
179.
Oberacher H Pitterl F Niederstätter H Weiss EM Stadelmann E Marksteiner J Parson W 《Analytical and bioanalytical chemistry》2006,386(1):83-91
The applicability of ion-pair reversed-phase high-performance liquid chromatography hyphenated to electrospray ionization
time-of-flight mass spectrometry (ICEMS) for the haplotyping of five SNPs (rs769223, rs4818, rs4986871, rs8192488, rs4680)
located within exon 4 of the human catechol-O-methyltransferase (COMT, EC 2.1.1.6) gene is demonstrated. Two differently sized
products of polymerase chain reaction—a 71-bp amplicon partially covering the sequence of a 124-bp amplicon—were used to determine
unequivocally the allelic states of the single nucleotide polymorphisms linked on both chromosomes. The two amplicons were
co-loaded onto the chromatographic column and simultaneously analyzed within a single gradient run. Using the described strategy,
101 individuals representing an Austrian population sample were typed. The obtained haplotype frequencies will serve as reference
values in future association studies to examine the impact of the COMT gene on neuropsychiatric disorders. Additionally, two
newly discovered polymorphic sites within the sequence of the COMT gene are described (a synonymous C>T mutation at the third
position of the amino acid codon 99 in the soluble COMT protein or 149 in the membrane-bound COMT protein; a non-synonymous
G>A substitution at the second position of the amino acid codon 95 in the soluble COMT protein or 145 in the membrane-bound-COMT
protein). 相似文献
180.
Favero LB Velino B Caminati W Arnason I Kvaran A 《The journal of physical chemistry. A》2006,110(33):9995-9999
The rotational spectra of the main isotopomer, of the (29)Si and of all (13)C isotopologues of axial and equatorial forms of 1-fluoro-silacyclohexane have been measured by conventional (only main species) and molecular beam Fourier transform microwave spectroscopy. r(0) and partial r(s) structures are given separately for the two forms. The main structural differences are discussed. From dipole moments and relative intensity measurements, a slight preference (E(Eq) - E(Ax) = 42 +/- 24 cm(-1)) for the axial conformer was found. The rotational spectra of some, the most intense, vibrational satellites have also been measured. They belong to the ring-puckering motions. 相似文献