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1. Characterizing Oxidatively Damaged Cotton Fabrics : Part II: A Model for the Catalytic Damage Phenomenon Using Electrogenerated Oxygen

Author:
Kokot, S.; Marahusin, L.; Schweinsberg, D.P.; Jermini, M.
Source:
Textile research journal 1994 v.64 no.12 pp. 710-716
ISSN:
0040-5175
Subject:
chemometrics,   etc   ; bleaching; cellulose; cotton; cotton fabric; electrochemistry; electrodes; hydrogen peroxide; infrared spectroscopy; models; oxygen; reflectance; textile fibers;     Show all 13 Subjects
Abstract:
... "Catalytic damage" occurs in cotton fabrics during hydrogen peroxide bleaching. The model for catalytic damage proposed previously by Meyer, Kokot, Weber, and Zürcher is compared with a laboratory simulation of cotton cellulose damage produced using electrogenerated oxygen species at metal electrodes. Additional electrochemical information is provided to support the previously proposed mechanism o ...
DOI:
10.1177/004051759406401202

2. Investigation of peak compression effects in packed column supercritical fluid chromatography using chemometrics

Author:
Carlsson, D.; Strode, J. T., III; Gyllenhaal, O.; Karlsson, A.; Karlsson, L.
Source:
Chromatographia 1997 v.44 no.5-6 pp. 289-294
ISSN:
0009-5893
Subject:
chemometrics,   etc   ; carbon; experimental design; models; supercritical fluid chromatography; temperature;     Show all 6 Subjects
Abstract:
... In this paper chemometrics have been used to study and characterize peak compression phenomena in packed column SFC. A carbon dioxide/2-methyl-1-propanol mobile phase was used in the experimental design (modifier concentration, temperature and pressure) and modelling part of the investigation. A cubic interaction term was needed in the model to obtain a reasonable fit, suggesting that all three pa ...
DOI:
10.1007/BF02466397

3. Haemolymph Pigment Composition as a Chemometric Indicator of Phase in the Desert Locust, Schistocerca Gregaria

Author:
Mahamat, Hassane; Hassanali, Ahmed; Munyinyi, David
Source:
International journal of tropical insect science 1997 v.17 no.2 pp. 199-204
ISSN:
1742-7592
Subject:
chemometrics,   etc   ; Schistocerca gregaria; absorbance; carotenoids; clearcutting; diet; hemolymph; insects;     Show all 8 Subjects
Abstract:
... The blue biliverdin pigment in the haemolymph of Schistocerca gregaria Forskål (Orthoptera: Acrididae) was shown to be associated with all the stages and ages of the solitary-reared (solitarious) insects, irrespective of their origin or diet. The pigment was absent or present in very small quantities in the crowd-reared (gregarious) insects. The ratio of absorbance at 460 nm and 680 ran, the forme ...
DOI:
10.1017/S1742758400016374

4. Furanic and phenolic composition of cider brandy. A chemometric study

Author:
Mangas, J.J.; Rodriguez, R.; Moreno, J.; Suarez, B.; Blanco, D.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.10 pp. 4076-4079
ISSN:
0021-8561
Subject:
chemometrics,   etc   ; apples; brandy; ciders; discriminant analysis; ethanolysis; furfural; least squares; lignin; manufacturing; models; oak barrels; oxidation; raw materials; syringic acid;     Show all 15 Subjects
Abstract:
... A chemometric study based on furanic and polyphenolic substances is presented for typifying cider brandies of different ages obtained from ciders made from freshly pressed apple must and from reconstituted apple concentrate. Univariate treatment of the furfural content is sufficient for characterizing the brandies according to the raw material employed in their manufacture, but no single variable ...
DOI:
10.1021/jf9701300

5. Novel tartaric acid isoflavone derivatives that play key roles in differentiating Japanese soy sauces

Author:
Kinoshita, E.; Ozawa, Y.; Aishima, T.
Source:
Journal of agricultural and food chemistry 1997 v.45 no.10 pp. 3753-3759
ISSN:
0021-8561
Subject:
chemometrics,   etc   ; algorithms; cluster analysis; daidzein; discriminant analysis; ethers; fermentation; genistein; manufacturing; mash; molecular weight; reversed-phase high performance liquid chromatography; soy sauce; spectral analysis; tartaric acid;     Show all 15 Subjects
Abstract:
... Nonvolatile components in various brands of Japanese fermented soy sauce were analyzed by gradient reversed phase HPLC. The resulting HPLC profiles were correctly assigned into their original brands by chemometric pattern recognition techniques, such as cluster analysis, linear discriminant analysis (LDA), linear discriminant analysis using genetic algorithm (GALDA), and SIMCA. Three key component ...
DOI:
10.1021/jf9702095

6. Chemometric characterization of TLC systems of the type silica-binary non-aqueous mobile phase in the analysis of flavonoids

Author:
Maciejewicz, W.; Soczewinski, E.
Source:
Chromatographia 2000 v.51 no.7-8 pp. 473-477
ISSN:
0009-5893
Subject:
chemometrics,   etc   ; chemical structure; chromatography; flavonoids; quantitative analysis; solutes;     Show all 6 Subjects
Abstract:
... Retention-mobile phase composition relationships have been determined for eighteen flavonoids chromatographed with non-aqueous systems of the type silicadiluent+polar modifier (S). The slopes of the plots depended on the molecular structures of the solutes, primarily on the number of hydroxyl groups. The selectivities and sequences depended on the diluent and modifier applied; plots ofR M against ...
DOI:
10.1007/BF02490487

7. Chemometric characterization of soil and plant pollution: Part 1: Multivariate data analysis and geostatistical determination of relationship and spatial structure of inorganic contaminants in soil

Author:
Zupan, Marko; Einax, Jürgen W.; Kraft, Jörg; Lobnik, Franc; Hudnik, Vida
Source:
Environmental science and pollution research international 2000 v.7 no.2 pp. 89-96
ISSN:
0944-1344
Subject:
chemometrics,   etc   ; cadmium; chromium; cluster analysis; copper; discriminant analysis; factor analysis; geostatistics; kriging; lead; multivariate analysis; nickel; pollutants; soil; soil pollution; variance; zinc; Slovenia;     Show all 18 Subjects
Abstract:
... Geostatistical and multivariate methods of data analysis are used to describe patterns of soil pollution with inorganic contaminants in Celje County, Slovenia. Groups of contaminants and polluted sites were identified using cluster analysis and confirmed with multidimensional variance and discriminant analysis. Factor analysis yields an identification of not directly observable relationships betwe ...
DOI:
10.1065/espr199910.008

8. RPHPLC as a tool for determining the congenericity of a set of 2,4-dihydroxythiobenzanilide derivatives

Author:
Józwiak, K.; Szumilo, H.; Senzcyna, B.; Niewiadomy, A.
Source:
Chromatographia 2000 v.52 no.3-4 pp. 159-161
ISSN:
0009-5893
Subject:
chemometrics,   etc   ; bioactive properties; chromatography; dissociation; hydrogen bonding; hydrophobicity; pH; quantitative analysis; quantitative structure-activity relationships;     Show all 9 Subjects
Abstract:
... During the chemometric analysis of 2,4-dihydroxythiobenzanilides by of RPHPLC, four of the derivatives were observed to have unexpectelly high lipophilicity. These substances also behaved abnormally as mobile phase pH was increased. The high hydrophobicity and the lack of dissociation of these substances result from the formation of additional internal hydrogen-bond. Lack of congenericity was also ...
DOI:
10.1007/BF02490447

9. Optimization of chromatographic systems for the high-performance thin-layer chromatography of flavonoids

Author:
Matysik, G.; Soczewinski, E.; Wójciak-Kosior, M.; Wojtasik, E.
Source:
Chromatographia 2000 v.52 no.5-6 pp. 357-362
ISSN:
0009-5893
Subject:
chemometrics,   etc   ; adsorbents; databases; ethyl acetate; flavonoids; glycosides; methanol; methylene chloride; silica; thin layer chromatography;     Show all 10 Subjects
Abstract:
... To characterize the retention and selectivity of separations of 23 flavonoids (aglycones and glycosides) relationships betweenR F and modifier concentration were determined for silica and diol adsorbents (with mixtures of ethyl acetate and methanol as mobile phases), for cyanopropyl silica (with mixtures of ethyl acetate and dichloromethane as mobile phases), for aminopropyl silica (with mixtures ...
DOI:
10.1007/BF02491032

10. Ionic binding of human serum albumin — dependence on pH and ionic strength: a chromatographic approach

Author:
Guillaume, Y. C.; Guinchard, C.; Robert, J. F.; Berthelot, A.
Source:
Chromatographia 2000 v.52 no.9-10 pp. 575-578
ISSN:
0009-5893
Subject:
chemometrics,   etc   ; calcium; cations; chromatography; electrostatic interactions; human serum albumin; ionic strength; magnesium; pH; solvents; temperature; thermodynamics;     Show all 12 Subjects
Abstract:
... A chemometric method was applied to investigate the binding mechanism of Ca²⁺ and Mg²⁺ to human serum albumin (HSA) using a bio-chromatographic approach. The effects of the bulk solvent pH, its ionic strength and column temperature on the transfer of Ca²⁺ and Mg²⁺ from the bulk solvent to immobilized human serum albumin as a stationary phase were studied. Thermodynamic parameters corresponding to ...
DOI:
10.1007/BF02789753

11. Resolution of the essential constituents of Ramulus cinnamomi by an evolving chemometric approach

Author:
Xu, Cheng-Jian; Liang, Yi-Zeng; Song, You-Qun; Li, Ji-Shan
Source:
Fresenius' journal of analytical chemistry 2001 v.371 no.3 pp. 331-336
ISSN:
0937-0633
Subject:
chemometrics,   etc   ; Oriental traditional medicine; chromatography; essential oils; factor analysis; mass spectrometry; volatile compounds;     Show all 7 Subjects
Abstract:
... The analysis of complex mixtures, such as those of traditional Chinese medicine (TCM), is difficult by conventional methods of analysis. Chemometric methods provide a new way to solve such problems. Subwindow factor analysis (SFA) paired with the evolving window orthogonal projection (EWOP) method, has been used as a new evolving approach to the resolution of volatile components of Ramulus cinnamo ...
DOI:
10.1007/s002160100977

12. Genotypic and phenotypic heterogeneity of Streptococcus thermophilus strains isolated from dairy products

Author:
Giraffa, G.; Paris, A.; Valcavi, L.; Gatti, M.; Neviani, E.
Source:
Journal of applied microbiology 2001 v.91 no.5 pp. 937-943
ISSN:
1364-5072
Subject:
chemometrics,   etc   ; Streptococcus thermophilus; cheeses; cluster analysis; dairy technology; fermentation; genetic variation; phenotypic variation; polymerase chain reaction; principal component analysis; starter cultures; sugars;     Show all 12 Subjects
Abstract:
... Aims: Forty strains of Streptococcus thermophilus isolated from dairy products were identified and typed by a polyphasic approach which included phenotypic and genotypic criteria. Methods and Results: Strains were identified by sugar fermentation pattern and species-specific PCR. Phenotypic diversity was evaluated by a chemometric model taking into account some biochemical characteristics (e.g. ac ...
DOI:
10.1046/j.1365-2672.2001.01464.x
PubMed:
11722674

13. A Rapid FTIR Spectroscopic Method for Estimation of Caffeine in Soft Drinks and Total Methylxanthines in Tea and Coffee

Author:
Paradkar, M.M.; Irudayaraj, J.
Source:
Journal of food science 2002 v.67 no.7 pp. 2507-2511
ISSN:
0022-1147
Subject:
chemometrics,   etc   ; Fourier transform infrared spectroscopy; caffeine; models; polymerase chain reaction; prediction; soft drinks; tea;     Show all 8 Subjects
Abstract:
... A rapid Fourier Transform infrared (FTIR) spectroscopic method was developed to estimate caffeine in a variety of soft drinks and total methylxanthine content in tea and coffee using a single calibration model. FTIR spectrum of pure caffeine was characterized, and the 2 spectral regions of 1500 to 1800 cm(-1) and 2800 to 3000 cm(-1) were used for quantitative estimation using Partial least square ...
DOI:
10.1111/j.1365-2621.2002.tb08767.x

14. Chemometrics for the classification of DOP olive oils

Author:
Bianchi, G.; Di Vincenzo, D.; Giansante, L.
Source:
Acta horticulturae 2002 no.586 pp. 599-602
ISSN:
0567-7572
Subject:
chemometrics,   etc   ; European Union; certification; discriminant analysis; fatty acid composition; models; olive oil; olives; saponification; thermal stability;     Show all 10 Subjects
Abstract:
... The work was aimed at making a contribution to olive oil DOP (Protected Denomination of Origin) certification by evaluating how genetical factors can give a typical chemical fingerprint to olive oils. The olive oil samples investigated were obtained from homogeneous samples of monovarietal olives grown in various Italian regions; the olives were collected during the 1996 November/December olive ha ...
DOI:
10.17660/ActaHortic.2002.586.126

15. Multivariate Analysis of Quality and Mineral Parameters on Golden Smoothee Apples Treated Before Harvest with Calcium and Stored in Controlled Atmosphere

Author:
Benavides, A.; Recasens, I.; Casero, T.; Soria, Y.; Puy, J.
Source:
Food science and technology international 2002 v.8 no.3 pp. 139-146
ISSN:
1082-0132
Subject:
chemometrics,   etc   ; acidity; apples; boron; calcium; data analysis; firmness; flowering; fruits; multivariate analysis; nitrogen; oxygen; phosphorus; storage time; texture; trees;     Show all 16 Subjects
Abstract:
... Pre-harvest calcium treatments were applied with the aim of increasing the calcium content and improving the textural parameters in Golden Smoothee apples. Apple trees were sprayed 6 or 12 times with ``Stopit'' (a commercial product) at a rate of 1% (v/v), beginning 60 days after full bloom. The fruit was harvested at commercial maturity and stored for four and six months in controlled atmosphere ...
DOI:
10.1106/108201302026164

16. A New Approach to the Characterization of Volatile Signatures of Cork Wine Stoppers

Author:
Boudaoud, Nawal; Eveleigh, Luc
Source:
Journal of agricultural and food chemistry 2003 v.51 no.6 pp. 1530-1533
ISSN:
0021-8561
Subject:
chemometrics,   etc   ; cork; volatile compounds; headspace analysis; principal component analysis; rapid methods; wines; mass spectrometry; stoppers;     Show all 9 Subjects
Abstract:
... This work describes a new method for the rapid characterization of volatile compounds of cork wine stoppers by a dynamic headspace method coupled to mass spectrometry (DHS-MS). This technique does not require any pretreatment of the sample. The global volatile signature of the cork is evaluated without real chromatographic separation of its constituents. For data analysis, the mass fragments of ea ...
DOI:
10.1021/jf025844b

17. A novel method for measuring concentrations of phase separated biopolymers: the use of confocal Raman spectroscopy with self-modelling curve resolution

Author:
Pudney, Paul D.A.; Hancewicz, Tom M.; Cunningham, Dale G.; Gray, Carolyn
Source:
Food hydrocolloids 2003 v.17 no.3 pp. 345-353
ISSN:
0268-005X
Subject:
chemometrics,   etc   ; microstructure; biopolymers; gelatin; dextran; Raman spectroscopy;     Show all 6 Subjects
Abstract:
... This paper examines the potential use of confocal Raman spectroscopy in measuring the concentration of phase separated biopolymers. It demonstrates that this can be done for both bulk phase separated systems and gelled microstructures. The developments in this work mean that the Raman method can now be applied to any mixtures of biopolymers, even when their spectra are highly overlapping. The key ...
DOI:
10.1016/S0268-005X(02)00097-8

18. Classification of monovarietal Italian olive oils by unsupervised (PCA) and supervised (LDA) chemometrics

Author:
Giansante, Lucia; Vincenzo Di, Daria; Bianchi, Giorgio
Source:
Journal of the science of food and agriculture 2003 v.83 no.9 pp. 905-911
ISSN:
0022-5142
Subject:
chemometrics,   etc   ; cultivars; discriminant analysis; fatty acids; fatty alcohols; models; olive oil; olives; prediction; principal component analysis; squalene; triterpenoids;     Show all 12 Subjects
Abstract:
... This research work was conducted to establish whether monovarietal olive oils could be differentiated by their basic classes of compounds, ie (a) fatty acids, (b) fatty alcohols, (c) polycyclic triterpenes and (d) squalene. The ratio values of biosynthetically correlated acids were also examined. The mentioned classes of compounds, formed in distinct biosynthetic compartments of the olive fruit, s ...
DOI:
10.1002/jsfa.1426

19. A New Two Dimensional Germinative Classification of Malting Barley Quality Based on Separate Estimates of Vigour and Viability

Author:
Møller, B.; Munck, L.
Source:
Czech journal of genetics and plant breeding 2004 v.40 no.3 pp. 102-108
ISSN:
1212-1975
Subject:
chemometrics,   etc   ; barley; beta-glucans; energy; germination; industry; least squares; malt; malting barley; models; plant breeders; quality control; spectroscopy; tetrazolium; viability; vigor;     Show all 16 Subjects
Abstract:
... It is surprising that not even today do germination data seem fully integrated with malting data in barley quality evaluation. In order to implement such an integration, pattern recognition multivariate data analysis (chemometrics) is essential. Inspired by the results from chemometric analyses of whole germination curves we tested a two-dimensional classification plot of barley samples based on s ...
DOI:
10.17221/3706-CJGPB

20. Computational screening of combinatorial catalyst libraries

Author:
Melville, James L.; Andrews, Benjamin I.; Lygo, Barry; Hirst, Jonathan D.
Source:
Chemical communications 2004 no.12 pp. 1410-1411
ISSN:
1364-548X
Subject:
chemometrics,   etc   ; catalysts; chemical compounds; chemical reactions; screening;     Show all 5 Subjects
Abstract:
... A catalyst design methodology, utilizing combinatorial synthesis in parallel with chemometric analysis, is presented, which considers the 3D steric and electrostatic properties of substituents about a constant core structure. ...
DOI:
10.1039/b402378a