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141.
Joanna Szpunar-obiska Claudia Witte Ryszard obinski Freddy C. Adams 《Fresenius' Journal of Analytical Chemistry》1995,351(4-5):351-377
A comprehensive review of the state-of-the-art of the separation of various organically-bound metals and metalloids for speciation analysis is presented. Recent developments in chromatographic (gas, liquid and supercritical fluid), electrophoretic (free-flow and gel) and fractionation techniques are discussed, followed by a survey of pertinent applications to speciation analysis for organometals and metalloids. The required sample characteristics for a given separation technique are specified and appropriate derivatization procedures are characterized. Methods applicable to the speciation of organic species of a particular element in various matrices are critically evaluated.List of abbreviations APS
ammonium pentanesulfonate
- CCC
counter current chromatography
- CZE
capillary zone electrophoresis
- DBT
dibutyltin
- DCyT
dicyclohexyltin
- DDTC
diethyldithicarbamate
- DEAE
diethylaminoethyl gel (anion exchanger)
- DEL
diethyllead
- DET
diethyltin
- DMA
dimethylarsinic acid
- DMGe
dimethylgermanium
- DMHg
dimethylmercury
- DML
dimethyllead
- DMSb
dimethylstibinic acid
- DMT
dimethyltin
- DPhT
diphenyltin
- DPrT
dipropyltin
- EDTA
ethylenediaminetetraacetate
- FFF
field flow fractionation
- GC
gas chromatography
- HEPES
4-(2-hydroxyethyl)-1-piperazine-ethanesulfonic acid
- HPLC
high performance liquid chromatography
- ICP
inductively coupled plasma
- IEC
ion exchange chromatography
- IIC
ion interaction chromatography
- LC
liquid chromatography
- MBT
monobutyltin
- MCyT
monocyclohexyltin
- MEA
monoethylarsinic acid
- MEHg
monoethylmercury
- MEL
monoethyllead
- MET
monoethyltin
- MIP
microwave induced plasma
- MMA
monomethylarsonic acid
- MMGe
monomethylgermanium
- MMHg
monomethylmercury
- MML
monomethyllead
- MMSb
monomethylstibonic acid
- MMT
monomethyltin
- MPhHg
monophenylmercury
- MPhT
monophenyltin
- MPrT
monopropyltin
- MS
mass spectrometry
- NAA
neutron activation analysis
- NaBS
sodium 1-butanesulfonate
- NaDS
sodium dodecylsulfonate
- NaPS
sodium pentanesulfonate
- PAGE
polyacrylamide gel electrophoresis
- PAR
4-(2-pyridylazo)resorcinol
- PIXE
proton induced X-ray emission
- QF
quartz furnace
- RPC
reversed phase partition chromatography
- SDS
sodium dodecyl sulfate
- SEC
size exclusion chromatography
- SFC
supercritical fluid chromatography
- TBAP
tetrabutylammonium phosphate
- TAL
tetraalkyllead
- TBT
tributyltin
- TCyT
tricyclohexyltin
- TeEL
tetraethyllead
- TEL
triethyllead
- TeML
tetramethyllead
- TET
triethyltin
- TGME
thioglycolic methyl ester
- THF
tetrahydrofuran
- TMA
trimethylarsinic acid
- TMAH
tetramethylammonium hydroxide
- TMGe
trimethylgermanium
- TML
trimethyllead
- TMT
trimethyltin
- TPhT
triphenyltin
- TPrT
tripropyltin
- Tris
tris(hydroxymethyl)aminomethane 相似文献
142.
Aubert B Bona M Boutigny D Couderc F Karyotakis Y Lees JP Poireau V Tisserand V Zghiche A Grauges E Palano A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Charles E Gill MS Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Orimoto TJ Pripstein M Roe NA Ronan MT Wenzel WA Sanchez Pdel A Barrett M Ford KE Hart AJ Harrison TJ Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M Peters K 《Physical review letters》2006,97(26):261803
We report measurements of the decays B(+)-->phiphiK(+) and B(0)-->phiphiK(0) using a sample of 231 x 10(6) BB pairs collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the Stanford Linear Accelerator Center. The branching fractions are measured to be B(B(+)-->phiphiK(+))=(7.5+/-1.0(stat)+/-0.7(syst)) x 10(-6) and B(B(0)-->phiphiK(0))=(4.1(-1.4)(+1.7)(stat)+/-0.4(syst)) x 10(-6) for a phiphi invariant mass below 2.85 GeV/c(2). 相似文献
143.
Aubert B Barate R Bona M Boutigny D Couderc F Karyotakis Y Lees JP Poireau V Tisserand V Zghiche A Grauges E Palano A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Charles E Gill MS Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Wenzel WA del Amo Sanchez P Barrett M Ford KE Harrison TJ Hart AJ Hawkes CM Morgan SE Watson AT Goetzen K Held T Koch H 《Physical review letters》2006,97(17):171803
The photon spectrum in B-->Xs gamma decay, where Xs is any strange hadronic state, is studied using a data sample of 88.5 x 10(6) e+ e- --> Upsilon(4S) --> BB decays collected by the BABAR experiment at the Stanford Linear Accelerator Center. The partial branching fraction, DeltaB(B --> Xs gamma) = (3.67+/-0.29(stat)+/-0.34(syst)+/-0.29(model)) x 10(-4), the first moment = 2.288+/-0.025+/-0.017+/-0.015 GeV, and the second moment E2(gamma) = 0.0328+/-0.0040+/-0.0023+/-0.0036 GeV2 are measured for the photon energy range 1.9 GeV < E gamma < 2.7 GeV. They are also measured for narrower E gamma ranges. The moments are then fit to recent theoretical calculations to extract the heavy quark expansion parameters m(b) and mu2(pi) and to extrapolate the partial branching fraction to E gamma > 1.6 GeV. In addition, the direct CP asymmetry A(CP)(B-->X(s+d gamma) is measured to be -0.110+/-0.115(stat)+/-0.017(syst). 相似文献
144.
Koczoń P Piekut J Borawska M Swisłocka R Lewandowski W 《Analytical and bioanalytical chemistry》2006,384(1):302-308
FT–IR and Raman experimental data were assigned to appropriate bond vibrations and used to compare the different electronic
charge distributions in the aromatic rings and carboxylic anions of various lithium, sodium, potassium, rubidium and caesium o-iodobenzoates and picolinates. Then principal component analysis (PCA) was applied in order to attempt to distinguish the
biological activities of these compounds according to selected band wavenumbers. The growth of the bacteria Escherichia coli and Bacillus subtilis and the yeasts Saccharomyces cerevisiae and Hansenula anomala under optimal growth conditions were measured after 24 hours of incubation by the classical plate method. The influence of
the picolinates and o-iodobenzoates on the growth of these microorganisms, again after 24 hours of incubation, was also measured and compared to
the effect of sodium benzoate, which was used as a reference material. In general, the o-iodobenzoates exhibited more activity against the microorganisms than the picolinates. A statistically significant linear
correlation between the spectral data and the degree of influence of a given compound on microorganism growth was established.
The correlation coefficients for the o-iodobenzoates were 0.696, –0.628, 0.693 and 0.755 for E. coli, B. subtilis, H. anomala and S. cerevisiae, respectively, and for the picolinates they were 0.818, 0.826, 0.821 and 0.877 for E. coli, B. subtilis, H. anomala and S. cerevisiae, respectively. Therefore, IR spectroscopy is shown to be a rapid and reliable analytical tool for preliminary estimation
of the antimicrobial properties of newly synthesized compounds, that can be applied before microbial performance tests. 相似文献
145.
Ryszard Kacprzyk 《Journal of Electrostatics》2010,68(2):190-195
A simplified analysis of the charge decay processes for samples equipped with different types of grounding electrodes is presented. It is shown that the electrical properties of the back electrode (injecting or blocking) can strongly influence the charge decay process for plane parallel dielectric samples. The theory is confirmed by experimental investigation. For the sample with blocking back electrode the 50% time decay parameter can be an order of magnitude higher compared to that obtained for injecting or side electrode. In practical situations charge decay with the plane parallel samples may be much slower than that predicted by measurements carried out according to current standards. 相似文献
146.
Pawel Lukaszczuk E. Borowiak-Palen Mark H. Rümmeli Ryszard J. Kalenczuk 《Applied Physics A: Materials Science & Processing》2010,100(2):505-510
In this contribution we present a systematic study on the dispersion of SWCNTs in a water-based solution of biocompatible
detergent: sodium deoxycholate (DOC). By avoiding harsh chemical conditions, which are known to damage nanotubes structure,
a stable SWCNTs suspension was created. Long term stirring of the solution led to preparation of a stable transparent solution,
containing well-dispersed isolated SWCNTs. The as-prepared dispersion remained stable and clear for two months. Optical absorption
spectroscopy was employed to measure SWCNTs suspension stability. Nanotube aggregation was evaluated through the tangential
mode (G mode) present in the Raman spectrum. High-resolution transmission electron microscopy was employed to observe the
mechanism of debundling process. 相似文献
147.
Arkadiusz Lewandowski 《Journal of Geometric Analysis》2018,28(3):2466-2476
We prove that given a family \((G_t)\) of strictly pseudoconvex domains varying in \(\mathcal {C}^2\) topology on domains, there exists a continuously varying family of peak functions \(h_{t,\zeta }\) for all \(G_t\) at every \(\zeta \in \partial G_t\). 相似文献
148.
Jerzy Grzybowski Hubert Przybycień Ryszard Urbański 《Set-Valued and Variational Analysis》2013,21(2):201-216
Any abstract convex cone S with a uniformity satisfying the law of cancellation can be embedded in a topological vector space $\widetilde{S}$ (Urbański, Bull Acad Pol Sci, Sér Sci Math Astron Phys 24:709–715, 1976). We introduce a notion of a cone symmetry and decompose in Theorem 2.12 a quotient vector space $\widetilde{S}$ into a topological direct sum of its symmetric subspace $\widetilde{S}_s$ and asymmetric subspace $\widetilde{S}_a$ . In Theorem 2.19 we prove a similar decomposition for a normed space $\widetilde{S}$ . In section 3 we apply decomposition to Minkowski–Rådström–Hörmander (MRH) space with three best known norms and four symmetries. In section 4 we obtain a continuous selection from a MRH space over ?2 to the family of pairs of nonempty compact convex subsets of ?2. 相似文献
149.
We report on the fabrication of two-dimensional polymeric photonic crystal membranes on the surface of silicon using visible-light multibeam interference lithography. The structures are created by the interference of three beams of a green laser. A polymer buffer layer doped with a Rhodamine B laser dye, interlaid between the lithography layer and the silicon substrate, suppresses the effects of strong reflection and nonradiative absorption of silicon on the interference pattern. Large-area defect-free photonic crystal membranes are experimentally realized on silicon surface. 相似文献
150.
We prove that the correlations present in a multipartite quantum state have an operational quantum character even if the state is unentangled, as long as it does not simply encode a multipartite classical probability distribution. Said quantumness is revealed by the new task of local broadcasting, i.e., of locally sharing preestablished correlations, which is feasible if and only if correlations are stricly classical. Our operational approach leads to natural definitions of measures for quantumness of correlations. It also reproduces the standard no-broadcasting theorem as a special case. 相似文献