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排序方式: 共有271条查询结果,搜索用时 15 毫秒
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So-called “quantized” algebras are popular objects of study in non-commutative algebra. Usually such algebras are either positively graded Ore domains R with R 0 = K a field and R = K[R 1], R 1 being a finite dimensional K vectorspace, or else filtered rings having a ring of forementioned type for its associated graded ring. We show that every discrete valuation of K extends to a valuation, in the sence of O. Schilling (cf. [S]), of the skewfield of fractions, Δ = Qcl (R), of the Ore domain R (Proposition 2.3. and Corollary 2.8.). Such extension property has long been known to fail for finite dimensional skewfields over K; its validity in the case of several quantized algebras may be viewed as a consequence of the rigidity of their defining relations. Our result opens the door for a more arithmetical study of Δ e.g. in case K is a numberfield or an algebraic function field of a curve; for an application in this direction we refer to a first version of some divisor calculus started in [VW]. 相似文献
34.
María Cristina Bustos Freddy Paiva Wolfgang Wendland 《Mathematical Methods in the Applied Sciences》1990,12(6):533-548
We present the control of continuous sedimentation in an ideal thickener as an initial and boundary value problem and construct the entropy solution. 相似文献
35.
Let H be a Hopf algebra with bijective antipode, α, β ∈ Aut
Hopf
(H) and M a finite dimensional (α, β)-Yetter-Drinfeld module. We prove that End(M) endowed with certain structures becomes an H-Azumaya algebra, and the set of H-Azumaya algebras of this type is a subgroup of BQ(k, H), the Brauer group of H. 相似文献
36.
Ding S Luan D Boey FY Chen JS Lou XW 《Chemical communications (Cambridge, England)》2011,47(25):7155-7157
We demonstrate a new hydrothermal method to directly grow SnO(2) nanosheets on a graphene oxide support that is subsequently reduced to graphene. This unique SnO(2)/graphene hybrid structure exhibits enhanced lithium storage properties with high reversible capacities and good cycling performance. 相似文献
37.
Li H Cao X Li B Zhou X Lu G Liusman C He Q Boey F Venkatraman SS Zhang H 《Chemical communications (Cambridge, England)》2011,47(36):10070-10072
Graphene oxide (GO) sheet is used as a novel substrate for dip-pen nanolithography (DPN). After GO is transferred onto SiO(2) using the Langmuir-Blodgett technique, CoCl(2) is patterned on both GO and exposed SiO(2) substrates simultaneously by DPN, which is used for growth of different structured carbon nanotubes. 相似文献
38.
39.
This paper reports the effect of transfer line (TL) internal diameter (i.d.) on gas chromatographic separation characteristics such as efficiency and speed, when a multicapillary (MC) column is used for speciation analysis of mercury. Five different TL consisting of fused-silica capillaries with 0.15, 0.20, 0.25, 0.32, and 0.53 mm i.d. are compared. The separation efficiency and total chromatographic run time are critically affected by the i.d. of the TL. Narrow capillaries (i.d.0.20 mm) produce minimum peak dispersion whereas wide capillaries result in narrow peaks and shorter chromatographic analysis times. A thermodynamic approach is proposed to describe the motion of the analytes through the separation column and TL. The model provides good agreement with the experimental data for high pressures (35 psig) and wide TL (0.25 mm i.d.).Dedicated to the memory of Wilhelm Fresenius 相似文献
40.
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