ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

1

Digitale Medien

Crystallinities of copolymers of ethylene and 1-alkenes (1988)

Clas, S.-D. ; Heyding, R. D. ; McFaddin, D. C. ; [weitere]

Bognor Regis [u.a.] : Wiley-Blackwell

Journal of Polymer Science Part B: Polymer Physics 26 (1988), S. 1271-1286

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0887-6266

Schlagwort(e): Chemistry ; Polymer and Materials Science

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie , Physik

Notizen: Random copolymers of ethylene with 1-butene, 1-octene, and 1-octadecene have been prepared using a homogeneous vanadium-based catalyst system. Comonomer contents determined by 13C-NMR analysis of polymer solutions are in the range 1-10 mol%. Crystallinities were estimated by means of density measurements, x-ray diffraction, differential scanning calorimetry, laser Raman spectroscopy, and CPMAS 13C-NMR spectroscopy. The results are compared with those obtained for heterogeneous copolymers of ethylene containing 1-4 mol% 1-butene. As the comonomer content is increased, the crystallinity decreases. The dimension perpendicular to the 110 plane in orthorhombic crystallites decreases linearly with crystallinity. This decrease in crystallite size is accompanied by an increase in the size of the orthorhombic unit cell. For copolymers containing large amounts of 1-octene and 1-octadecene, a second crystalline form appears. Differences in estimates of crystallinity are discussed in terms of looser packing in highly branched copolymers and the extent to which the second crystalline form participates in the phase structure.

Zusätzliches Material: 6 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/polb.1988.090260611

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

2

Digitale Medien

Determination of chlorpromazine and its major metabolites by gas chromatography/mass spectrometry: Application to biological fluids (1985)

Gruenke, L. D. ; Craig, J. Cymerman ; Klein, F. D. ; [weitere]

Chichester : Wiley-Blackwell

Biological Mass Spectrometry 12 (1985), S. 707-713

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 1052-9306

Schlagwort(e): Chemistry ; Analytical Chemistry and Spectroscopy

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie

Notizen: A method for the quantitative determination of chlorpromazine and five of its major metabolites in a single sample of biological fluid in the ng/ml range has been developed utilizing gas chromatography/mass spectrometry with selected ion recording. The assay is highly specific and quantification is accomplished by an inverse stable isotope dilution technique, using deuterium-labeled variants of the compounds as internal standards. In this way the concentrations of chlorpromazine and five of its major metabolites (the sulfoxide, the N-oxide, the monodemethylated, the didemethylated, and the 7-hydroxylated compounds) can be determined in biological fluids. Levels in humans have been measured both in plasma and in red blood cells and are compared to those found in related in vitro studies.

Zusätzliches Material: 2 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/bms.1200121207

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

3

Digitale Medien

Two-dimensional proton NMR studies on poly(VPGVG) and its cyclic conformational correlate, cyclo(VPGVG)3 (1989)

Urry, D. W. ; Chang, D. K. ; Krishna, N. R. ; [weitere]

New York : Wiley-Blackwell

Biopolymers 28 (1989), S. 819-833

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0006-3525

Schlagwort(e): Chemistry ; Polymer and Materials Science

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie

Notizen: Two-dimensional nuclear Overhauser enhancement (2D NOESY) data are reported for the polypentapeptide of elastin, poly(VPGVG), and the cyclopentadecapeptide, cyclo(VPGVG)3. In both, the repeating type II Pro2-Gly3 β-turn can be derived from the NOE data, providing confirmation of many previous studies. In addition, other through-space connectivities are detailed that also compare favorably with previously determined crystal and solution structures for cyclo(VPGVG)3. Also, near identical data for the cyclopentadecapeptide and the polypentapeptide demonstrate the cyclic conformation-linear (helical) conformational correlate relationship between the two molecules. The 2D NOESY experiment is seen to be an effective means of establishing the presence or absence of a conformational relationship between a cyclic repeating sequence and its higher molecular weight linear counterpart. This is an approach of substantial practical value when developing the conformation of sequential polypeptides and when attempting to identify the presence of the conformation of a repeating peptide sequence within a more complex primary structure.Having established the basic conformational relationship between a cyclic conformation and its linear helical counterpart, cross peaks present in the linear helical structure that are not present in the cyclic conformational correlate can provide information on the interactions between adjacent turns of the helix. In this connection, a ValγCH3 ↔ ProβCH2 interaction is reported that can be the basis for determining the number of pentamers per turn of helix once it is determined whether it is dominantly the Val1 or Val4γCH3 that is interacting with the Pro2βCH2.

Zusätzliches Material: 7 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/bip.360280404

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

4

Digitale Medien

High performance liquid chromatography (HPLC) of natural products part VI.For part V, see [1] Sulfoxides of penicillin N and cephalosporin c and their role in biosynthesis of β-lactam antibiotics (1984)

Kukolja, S. ; Miller, R. D. ; Duckworth, D. C. ; [weitere]

New York, NY : Wiley-Blackwell

Helvetica Chimica Acta 67 (1984), S. 876-884

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0018-019X

Schlagwort(e): Chemistry ; Organic Chemistry

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie

Notizen: Pure pencillin N α-sulfoxide (1) and penicillin N β-sulfoxide (2) were obtained by HPLC and tested as substrates for deacetoxycephalosporin C synthetase (DXCS). Neither one of the sulfoxides was utilized under conditions of conversion of penicillin N (8) to deacetoxycephalosporin C (9). The cephalosporin C α and β-sulfoxides (3 and 4, resp.) were also prepared. Relative stabilities of the sulfoxides 3 and 4 are discussed by interpretation of the 13C-NMR spectra.

Zusätzliches Material: 9 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/hlca.19840670329

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

5

Digitale Medien

Thermal behavior of cast polyurethane elastomers (1988)

Pandya, M. V. ; Deshpande, D. D. ; Hundiwale, D. G.

New York, NY [u.a.] : Wiley-Blackwell

Journal of Applied Polymer Science 35 (1988), S. 1803-1815

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0021-8995

Schlagwort(e): Chemistry ; Polymer and Materials Science

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie , Maschinenbau , Physik

Notizen: Thermal properties like glass transition temperature (Tg), initial decomposition temperature (idt), integral procedural decomposition temperature (ipdt), and temperature at various % weight loss of a number of polyurethane systems are reported in this paper. Glass transition temperature was determined on TMA, and other thermal properties were determined by thermogravimetry. The experiments were designed to understand various factors such as length of chain extender moiety, flexibility of chain extender units by substitution of ether link in the diol chain, nature of bonds (unsaturation) in the extender unit, and nature of diisocyanates.

Zusätzliches Material: 1 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/app.1988.070350708

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

6

Digitale Medien

Consistent values of rate parameters in free radical polymerization systems (1988)

Buback, M. ; Garcia-Rubio, L. H. ; Gilbert, R. G. ; [weitere]

New York : Wiley-Blackwell

Journal of Polymer Science: Polymer Letters Edition 26 (1988), S. 293-297

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0887-6258

Schlagwort(e): Chemistry ; Polymer and Materials Science

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie

Zusätzliches Material: 1 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/pol.1988.140260704

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

7

Digitale Medien

Ethylene polymerization over organochromium catalysts: A comparison between closed and open pentadienyl ligands (1987)

Freeman, Jeffrey W. ; Wilson, David R. ; Ernst, Richard D. ; [weitere]

Bognor Regis [u.a.] : Wiley-Blackwell

Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 2063-2075

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0887-624X

Schlagwort(e): Chemistry ; Polymer and Materials Science

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Chemie und Pharmazie

Notizen: Divalent organochromium compounds, Cr(Lig)2, often become active catalysts for the polymerization of ethylene when deposited onto an oxide carrier such as silica or aluminophosphate. Hydroxyl groups are thought to react, releasing one ligand and binding the chromium to the surface. The behavior of the catalyst is then governed by the remaining ligand and the type of carrier. In this study two types of ligands were investigated: cyclopentadienyl and its open ring analog dimethylpentadienyl. This small difference in the type of ligand produces a fundamental difference in the polymerization mechanism. For comparison the mixed ligand chromocene, with one open and one closed ligand, was also synthesized and tested for polymerization.

Zusätzliches Material: 3 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/pola.1987.080250804

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

8

Digitale Medien

Modifications to the Mackereth oxygen electrode (1967)

Flynn, D. S. ; Kilburn, D. G. ; Lilly, M. D. ; [weitere]

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 9 (1967), S. 623-625

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0006-3592

Schlagwort(e): Chemistry ; Biochemistry and Biotechnology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung

Zusätzliches Material: 1 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/bit.260090415

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

9

Digitale Medien

Laboratory studies on the suitability of a fertilizer-tap water medium for mass culture of algae (1985)

Geldenhuys, D. J. ; Walmsley, R. D. ; Toerien, D. F.

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 27 (1985), S. 1572-1576

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0006-3592

Schlagwort(e): Chemistry ; Biochemistry and Biotechnology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung

Zusätzliches Material: 4 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/bit.260271108

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext

10

Digitale Medien

Cultivation of a filamentous mold in a glass pilot-scale airlift fermentor (1981)

Malfait, J. L. ; Wilcox, D. J. ; Mercer, D. G. ; [weitere]

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 23 (1981), S. 863-877

zur Merkliste hinzufügen auf der Merkliste

Details

ISSN: 0006-3592

Schlagwort(e): Chemistry ; Biochemistry and Biotechnology

Quelle: Wiley InterScience Backfile Collection 1832-2000

Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung

Notizen: Results of pilot plant studies using a glass airlift fermentation device (55 liter fermentation volume) have proven the relative merits of such a system in the fermentation of a filamentous mold, Monascus purpureus, on 4% (w/w) starch media. The resultant overall yield of cell mass (Yx/s) of 0.38 was an appreciable increase over the 0.32 obtained with a pilot scale stirred tank fermentor previously studied. Power requirements of the airlift fermentor were approximately 50% of those for the mechanically agitated system. The lack of mechanical shear in the airlift system provides a more gentle environment or the cultivation of organisms than does the high degree of shear prevalent in the mechanically agitated vessels. Mass transfer of oxygen to the aqueous phase of the fermentation volume is improved significantly through use of the airlift device. Mass transfer coefficients in the range of 200 reciprocal hr were obtained to approximately 80 reciprocal hr in the stirred tank fermentor.

Zusätzliches Material: 8 Ill.

Materialart: Digitale Medien

URL: http://dx.doi.org/10.1002/bit.260230416

Permalink

	Standort	Signatur	Erwartet	Verfügbarkeit

Andere fanden auch interessant ...

Artikel (Nationallizenzen)

Volltext