ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Investigation of the effect of laser treatment on the longitudinal and transverse velocity of an aluminum alloy (2002)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 91 (2002), S. 5775-5781 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The velocities of longitudinal and transverse waves for aluminum alloy 2024-T62 shocked by a high-power Nd: Glass laser are investigated by a laser ultrasonics method. The results show that the velocity of the longitudinal wave measured after the laser-shock processing increases at the center and decreases at the edge of the laser-shocked area (LSA). The maximum relative increase is 28% and the maximum decrease up to 10%, when compared with that measured before the alloy was shocked by laser processing. The velocity of the transverse wave decreases at any position within LSA, the maximum relative decrease being 13%. The decrease at the edge of LSA is larger than that at the center. © 2002 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1452761
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    MRI study of the inhibitory effect of new spin traps on in vivo CCl"4-induced hepatotoxicity in rats
    Amsterdam : Elsevier
    Free Radical Biology and Medicine 14 (1993), S. 677-681 
    Details
    ISSN: 0891-5849
    Keywords: CCl"4 ; EM ; Free radicals ; Hepatotoxicity ; In vivo ; M"3PO ; MRI ; PhM"2PO ; Spin traps
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0891-5849(93)90150-S
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Prophylactic effects and spin trapping efficacies of 2-substituted DMPO spin traps
    Amsterdam : Elsevier
    Free Radical Biology and Medicine 15 (1993), S. 509 
    Details
    ISSN: 0891-5849
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0891-5849(93)90331-N
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Effects of organic modifier and ion-pair reagent in liquid chromatography (1993)
    Springer
    Chromatographia 35 (1993), S. 390-394 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Electrostatic model ; Ion-pair reagent ; Organic modifier ; Prediction of k′ values
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The capacity factors of phenylamine and naphthylamine sulphonic acids in reversed-phase, ion-pair liquid chromatography (RP-IPC) were measured. The combined effects of organic modifier (Cb) and ion-pair reagent concentration (Cp) on retention follow an equation based on the electrostatic model: $$\ln k' = a + b lnC_p + cC_b $$ the experimental value of b correlates well with the value of 0.5 z (z=charge on analyte ion) predicted for mono and divalent ions. The measured value of b is, however, lower than that predicted for trivalent ions, which may be due to the effective number of charges being less than the apparent number. The absolute values of a and c are much larger than those in RP-HPLC in the absence of an ion-pair reagent, quantitative correlation of a and c with retention values in RP-HPLC and solute charges has been observed and a good linear relationship between a and c has been obtained, strongly supporting the validity of the electrostatic retention model. A critical value, R, at which the negative effect of methanol on retention is equal to the positive effect of the ion-pair reagent (TBAI) has been proposed. The critical values obtained are related to the behaviour of the solute, the ion-pair reagent and the stationary and mobile phases, and lies between −0.04 and −0.065 in most cases, which means that the increase by exp times (=2.718×) the ion-pair concentration the original is equivalent to a decrease of 0.04–0.065 in volume fraction of methanol
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02278591
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Prediction of retention of O-ethyl, O-aryl and N-isopropyl phosphoroamidothioates in RP-HPLC from molecular structure parameters (1991)
    Springer
    Chromatographia 31 (1991), S. 143-146 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Molecular structure parameters ; Prediction of retention ; Phosphoroamidothiotes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Multi-variable regression analysis between lnkw, c (in retention equation lnk′=lnkw+cCb) and molecular structure parameters, including hydrophobicity, electric effect, field effect and position-specific effect constant, was carried out with O-ethyl, O-aryl and N-isopropyl phosphoroamidothioates as test solutes. With these quantitative relationships, the retention behaviour of these solutes for different mobile phase compositions was predicted. The results showed that there are only 26.7% of total, experimentally measured, capacity factors with relative deviations larger than 5% and only 2.2% with deviations larger than 10%, which means that it is possible to apply the method reported to predict retention values for qualitative purposes for different mobile phase compositions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02274562
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Effect of inorganic salt concentration on the retention value in reversed phase ion-pair liquid chromatography (1991)
    Springer
    Chromatographia 32 (1991), S. 538-542 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Ion-pair separation ; Salt concentration ; Charge number of solute ; Gouy-Chapman theory
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Thermodynamic and numerical treatments have been combined with Gouy-Chapman theory were to show that the effect of the salt concentration on the capacity factor in reversed-phase ion-pair liquid chromatography (RP-IPC) can be expressed as lnk′=A+blnCs. The parameter B is related to the charge number of the solute, and the parameter A is determined by both electrostatic and nonelectrostatic interaction, and can the linearly correlated with logarithm of the capacity factor in RP-HPLC for the solute with one negative charge. It also been observed that the electrostatic interaction is reduced with increasing salt concentration in RP-IPC, and this effect is more remarkable for solutes with more than the one negative charge of sulphonic acids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02327899
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Role of solute hydrophobicity and charges in reversed-phase ion-pair liquid chromatography (1991)
    Springer
    Chromatographia 32 (1991), S. 329-333 
    Details
    ISSN: 1612-1112
    Keywords: Ion-pair chromatography ; Solute charges ; Solute hydrophobicity ; Quantitative correlation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The Logarithm of capacity factor in RP-HPLC and solute charges have been selected as descriptors of solute hydrophobicity and electrostatic interaction respectively. It has been observed that the logarithm of capacity factors (ln k ip ′ ) for a solute with one, two and three negative charges in RP-IPC can be well correlated with the logarithms of capacity factors (ln kR p ′ ) in RP-HPLC and solute charges (ne). Both the solute hydrophobicity and solute charges with opposite sign to those of the ion-pair reagent made a positive contribution to retention in RP-IPC. The logarithm of capacity factor linearly decreases with organic modifier concentration (Cb) and the logarithm of the inorganic salt concentration (lnCs). The intercept (ln k ip ′ , A) and slope (cip,B) values of a linear relationship between ln kR p ′ vs. Cb and ln k ip ′ vs. ln C5 also can be well correlated with ln kR p ′ and ne. The solute hydrophobicity and solute charges also made a positive contribution to the parameters ln k ip w and A, but a negative contribution to parameter cip. The parameter B, however is mainly determined by the solute charges.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02321429
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Correlation free-solution capillary electrophoresis migration times of small peptides with physicochemical properties (1993)
    Springer
    Chromatographia 37 (1993), S. 429-432 
    Details
    ISSN: 1612-1112
    Keywords: Capillary electrophoresis ; Migration time prediction ; Small peptides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A series of small peptides containing varying degree of charge and size was used to study the effects of physicochemical properties on migration in free-solution capillary electrophoresis (FSCE). A semiempirical relationship between migration time under acidic conditions and the square root of molecular weight divided by the quantity of the number of the positively ionizable groups has been established. The ionization of the carboxyl terminal group in the polypeptides is negligible under acidic conditions. The relationship developed from this work has been used for the prediction of migration parameters in free solution capillary electrophoresis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02272260
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Combined effect of organic modifier concentration and column temperature on retention in reversed-phase ion-pair liquid chromatography (1992)
    Springer
    Chromatographia 34 (1992), S. 14-18 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Ion-pairing ; Temperature effects ; Organic modifier concentration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The retention behavior of phenylamine and naphthylamine sulphonic acid was evaluated in reversed-phase ion-pair liquid chromatography as a function of organic modifier concentration and column temperature. It has been observed that the logarithm of capacity factors decrease linearly with organic modifier concentration, and there is a good linear relationship between the intercept and slope for this relationship. Phenylamine and naphthylamine sulphonic acid retention decreases with increase in column temperature. A linear dependence of lnk ip ′ on the reciprocal of the absolute temperature, the Van't Hoff plot, was observed over the column temperature range studied, and the standard enhalpic change (ΔHo) for these sulphonic acid transfers from the mobile phaser to the stationary phase was determined. ΔHo was dependent on the solute structure and in the range from 2.5 Kcal/mol to 5.5 Kcal/mol, which is close to that observed in RP-HPLC. The enthalpy/entropy compensation effect was evaluated by plotting lnk ip(T) ′ vs. −ΔHo, and the apparent differences in retention mechanisms between the analytes were observed, which may arise from the significant differences in their configuration, hydrophobicity and the charges of the solutes as well as the complex retention processes of RP-IPC.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02290452
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Determination of drug-protein interactions by combined microdialysis and high-performance liquid chromatography (1997)
    Springer
    Chromatographia 44 (1997), S. 205-208 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Microdialysis ; Carbamazepine ; Human serum albumin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary A simple and rapid method for determination of the parameters of the interaction between drugs and protein, including the association constant and the number of binding sites, has been developed by use of a microdialysis sampling technique combined with high-performance liquid chromatography. The drug and protein (carbamazepine (5H-dibenz[b,f]flazepine-5-carboxamide, CBZ) and human serum albumin (HSA) were used as examples) were mixed in different molar ratios in 0.067 M potassium phosphate buffer, pH 7.4, and incubated at 37°C in a water-bath. The microdialysis probe was the used to sample the mixed CBZ-HSA solution at a perfusion rate of 1 μL min−1. The concentration of CBZ in the microdialysate was determined by reversed-phase high-performance liquid chromatography. Relative recovery (R), determined in vitro under similar conditions, was approximately 42.7%; theRSD ofR was approximately 1.85%. The estimated association constant (K) and the number of the binding sites,n, on one molecule of HSA were 1.06×104 M−1 and 0.880, respectively, which is in good agreement with the literature values determined by high-performance frontal analysis. The potential use of microdialysis is also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02466457
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...