Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Improved chiral recognition of some compounds via the simultaneous use of β-cyclodextrin and its permethylated derivative in a reversed-phase high-performance liquid chromatographic system
    Amsterdam : Elsevier
    Journal of Chromatography A 625 (1992), S. 349-352 
    Details
    ISSN: 0021-9673
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0021-9673(92)85219-J
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The chromatic connectivity of graphs (1988)
    Springer
    Graphs and combinatorics 4 (1988), S. 229-233 
    Details
    ISSN: 1435-5914
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract A graphG ischromatically k-connected if every vertex cutset induces a subgraph with chromatic number at leastk. This concept arose in some work, involving the third author, on Ramsey Theory. (For the reference, see the text.) Here we begin the study of chromatic connectivity for its own sake. We show thatG is chromaticallyk-connected iff every homomorphic image of it isk-connected. IfG has no triangles then it is at most chromatically 1-connected, but we prove that the Kneser graphs provide examples ofK 4-free graphs with arbitrarily large chromatic connectivity. We also verify thatK 4-free planar graphs are at most chromatically 2-connected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01864163
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Interactions Between Environmental Selenium and Sulphoxy Radicals (2000)
    Springer
    Journal of atmospheric chemistry 35 (2000), S. 19-31 
    Details
    ISSN: 1573-0662
    Keywords: aqueous phase ; cloud chemistry ; selenium ; sulphoxy radicals ; sulphur oxidation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Chemical interactions between sulphoxy radical anions and elemental Se were investigated to show the influence of SO2 pollution on the atmospheric fate of selenium. Laboratory experiments were performed with elemental Se plates or fine powder exposed to sulphoxy radicals formed in situ during the autoxidation of SO2 dissolved in water. Impacts of the radicals were followed examining the topographic surface changes of Se (atomic force microscopy, AFM) and measuring the S(IV) autoxidation rate, essentially decreased in the presence of Se (conductometry). The experiments showed that remobilization of water insoluble selenium (elemental Se) may take place not only in atmosphere (cloud waters), but also in surface waters, soil and sediments contacting with SO2 polluted air. By scavenging radicals, selenium causes the retardation of the S(IV) autoxidation to sulphuric acid (acid rain), thus contributing to long-distance transport of unreacted S(IV). The more general problem of sulphoxy radical-induced atmospheric corrosion has been brought forward into consideration, as the radicals appear capable to damage diverse solid surfaces.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006227327933
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Bromodeoxyuridine immunohistochemical determination of the lengths of the cell cycle and the DNA-synthetic phase for an anatomically defined population (1989)
    Springer
    Journal of neurocytology 18 (1989), S. 311-318 
    Details
    ISSN: 1573-7381
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A cumulative labelling protocol using 5-bromo-2′-deoxyuridine (BUdR) was followed to determine: (1) the growth fraction (i.e., the proportion of cells that comprise the proliferating population), (2) the length of the cell cycle, and (3) the length of the DNA-synthetic phase (S-phase) for proliferative cells in the dentate gyrus of the mouse. On postnatal day 20 (P20), C57BL/6J mice were injected with BUdR at two hour intervals for a total period of 12 hours. Animals were sacrificed at selected intervals, and the brains were processed for immunohistochemistry using a monoclonal antibody directed against single-stranded DNA containing BUdR. The numbers of BUdR-labelled and unlabelled cells in sections through the hilus of the dentate gyrus were counted. The number of BUdR-labelled cells increased linearly from an initial value of about 12% of the total number of cells to a maximum value of just over 24% of the total. These findings indicate that, at P20, a maximum of 24.2 ± 1.2% of the cells in the dentate hilus are part of the proliferating population. The calculated length of the cell cycle of the cells comprising the intrahilar proliferative zone was estimated to be 16.1 ± 0.8h. The length of the S-phase was estimated at 8.0 ± 0.4 h. In addition, mathematical analysis, using one and two population models, indicates that over 90% of the proliferating cells in the dentate hilus at this age comprise a single population at least in terms of the lengths of the cell cycle and the S-phase. This protocol provides a convenient method for thein situ analysis of the cell cycle for anatomically defined proliferative populations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01190834
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    BUdR as an S-phase marker for quantitative studies of cytokinetic behaviour in the murine cerebral ventricular zone (1992)
    Springer
    Journal of neurocytology 21 (1992), S. 185-197 
    Details
    ISSN: 1573-7381
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary BUdR incorporation into replicating DNA, detected immunohistochemically, is used as an S-phase marker in the proliferative cell populations of the cerebral wall of the mouse embryo on the 14th gestational day (E14). The analysis initiates a series of studies concerned with the cytokinetic behaviour and cell output of proliferative populations involved in neocortical histogenesis. On E14 there are two periventricular proliferative zones in the cerebral wall. These are the ventricular and subventricular zones. The ventricular zone is a pseudostratified epithelium. DNA replication occurs with the cell nucleus in the outer zone of the epithelium and mitoses at the ventricular surface. Prior applications of BUdR for studies of cytogenesis in the CNS have been extended in two principal ways: (1) basic fuchsin was used as counterstain for BUdR-negative nuclei and (2) labelling indices were determined separately in strata or bins, 10 μm in height, through the full depth of the ventricular zone and overlying cerebral wall. It was established that a single injection of 50 μg g−1 into the pregnant dam was associated with labelling of 100% of nuclei in S-phase over an interval extending from 15 min to at least 2.0 h after injection. The zone where nuclei are undergoing S-phase (S-phase zone) extends through the outer four bins of the ventricular zone. The method has high quantitative reproducibility with anse for labelling indices in bins within the S-phase zone less than 10% of the average values. Evidence is provided that BUdR incorporation is initiated with the nucleus in the outer aspect of the S-phase zone. The efficiency of incorporation of the marker is reduced as nuclei near the end of DNA replication and move to the inner aspect of the S-phase zone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01194977
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A structural theory of matrix-defined finite automata (1965)
    Springer
    Studia logica 16 (1965), S. 115-116 
    Details
    ISSN: 1572-8730
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Philosophy
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02176146
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Dwie definicje równoważności automatów (1970)
    Springer
    Studia logica 26 (1970), S. 16-16 
    Details
    ISSN: 1572-8730
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Philosophy
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02283838
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    The endomorphism spectrum of an ordered set (1995)
    Springer
    Order 12 (1995), S. 45-55 
    Details
    ISSN: 1572-9273
    Keywords: Primary: 06A06, 05C35 ; Secondary: 05B05, 03C13 ; Ordered set ; order-preserving map ; endomorphism ; retract ; reflexive graph ; rigid ; projective plane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Theendomorphism spectrum of an ordered setP, spec(P)={|f(P)|:f ∈ End(P)} andspectrum number, sp(P)=max(spec(P)\{|P|}) are introduced. It is shown that |P|〉(1/2)n(n − 1) n − 1 implies spec(P) = {1, 2, ...,n} and that if a projective plane of ordern exists, then there is an ordered setP of size 2n 2+2n+2 with spec(P)={1, 2, ..., 2n+2, 2n+4}. Lettingh(n)=max{|P|: sp(P)⩽n}, it follows thatc 1 n 2⩽h(n)⩽c 2 n n+1 for somec 1 andc 2. The lower bound disproves the conjecture thath(n)⩽2n. It is shown that if |P| − 1 ∈ spec(P) thenP has a retract of size |P| − 1 but that for all κ there is a bipartite ordered set with spec(P) = {|P| − 2, |P| − 4, ...} which has no proper retract of size⩾|P| − κ. The case of reflexive graphs is also treated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01108589
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Computer simulation of non-linear preparative chromatography processes (1989)
    Springer
    Chromatographia 28 (1989), S. 293-299 
    Details
    ISSN: 1612-1112
    Keywords: Preparative liquid chromatography ; Column overloading ; Computer simulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A theory of non-linear chromatography based on the mass balance equation is presented. The model is a system of partial differential equations and it includes axial dispersion in the mobile phase, flow in the mobile phase and mass transfer between phases. In the case of the injection of a mixture competition between components for places in the stationary or the mobile phase is taken into account. In the paper are discussed: numerical calculations of concentration and volume overloading and the effect of the mutual influence of the components of the injected mixture on the process of mass transfer between phases. Additionally, results of experiments for convex and concave adsorption isotherms are presented. In both cases the results obtained qualitatively confirm the theoretical analyses.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02260778
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Host-guest interactions of calix[4]resorcinarenes with benzene derivatives in conditions of reversed-phase high-performance liquid chromatography. Determination of stability constants (1998)
    Chichester : Wiley-Blackwell
    Journal of Physical Organic Chemistry 11 (1998), S. 426-437 
    Details
    ISSN: 0894-3230
    Keywords: calix[4]resorcinarenes ; organophosphorus compounds ; solvatophobic interactions ; host-guest complexation ; high-performance liquid chromatography ; x-ray analysis ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Reversed-phase high-performance liquid chromatography [LiChrosorb RP-18,UV detection at 254 nm and acetonitrile-water (86:14,v/v) as mobile phase] was applied to studies of the host-guest complexation of tetraalkylcalix[4]resorcinareneoctols and their upper rim phosphoryl, sulfonyl and dialkylaminomethyl derivatives with some aromatic guests in the mobile phase. It was shown that the formation of the inclusion complexes results in changes in the retention of aromatic guests and improves their separation. Stability constants of the complexes were calculated from the dependences of the l/k′ values of the aromatic guest on the concentration of the calix[4]resorcinarene in the mobile phase. The molecular structure of 4,6,16,18-tetrahydroxy-10,12,22,24-tetrakis(dipropoxyphosphoryloxy)-2,8,14,20-tetramethylcalix[4]resorcinarene (12) was determined. Crystal data for 12 are P21/n, a  =  16.708(9) Å, b  =  18.683(6) Å, c  =  20.243(5) Å, β  =  95.75(3)°, V  =  6287(4) Å3 and Z  =  4. Compound 12 exists in a boat conformation, in which two opposite unsubstituted resorcinol rings of the macrocyclic skeleton lie in the plane formed by four methine bridges and two diphosphorylated rings are perpendicular to the plane. © 1998 John Wiley & Sons, Ltd.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...