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511.
E. Ühlein E. Best H. Bergmann P. Kratochvíl A. Sippel 《Colloid and polymer science》1968,226(1):83-96
Ohne Zusammenfassung 相似文献
512.
GÜnther Trautmann 《Archiv der Mathematik》1967,18(2):188-196
Ohne ZusammenfassungHerrn Prof. Dr.Hans Grauert danke ich an dieser Stelle recht herzlich fÜr viele Anregungen und Ratschläge. 相似文献
513.
The fourth-order contributions of WW, Z? and ZZ intermediate states to the S-matrix elements of μμ elastic scattering have been calculated by dispersion theoretic techniques in the U-gauge. It is shown that the contributions are finite and very small compared to the low-order contributions. It is also shown that the main part of these finite contributions comes from the WW intermediate state. 相似文献
514.
Summary
Taql endonuclease was purified by high performance ion exchange liquid chromatography with linear gradient elution. Of the chromatographic
media tested as mobile phases for the HPLC purification ofTaql endonuclease, sodium acetate (pH 5.0) and phosphate (pH 7.0) buffers were appropriate for use with cation exchange columns,
and L-histidine (pH 6.0) and Tris (pH 8.0) buffers with anion exchange columns. 相似文献
515.
Abstract In this study the graft copolymerization of acrylamide (AAm) on swollen poly(ethylene terephthalate) (PET) fibers using cerium ammonium nitrate (CeAN) initiator was investigated. Five organic solvents, dimethylsulfoxide (DMSO), morpholine, acetic acid (HAc), n-butanol, and 1,2-dichloroethane (DCE), were used as swelling agents. DMSO was found to be the most suitable swelling agent. Solvent diffusion into the fibers was observed to increase with treatment time and temperature. The optimum graft yield was obtained when fibers were grafted after having been swollen in DMSO for a period of 1 hour at 140°C. Variation of graft yield with polymerization time and temperature, and monomer, initiator, and acid concentrations were investigated. Graft yields were observed to increase initially with polymerization time, then to level off, and were found to increase up to a certain monomer and Ce4+ concentration, then to decrease slightly. The effect of grafting on such fiber properties as diameter, viscosity, and moisture gain were also investigated. 相似文献
516.
517.
Ohne Zusammenfassung 相似文献
518.
W. Hückel C. Mahr R. Haul E. Buddecke H. H. Pfeiffer S. Hünig F. Würstlin A. Giller A. Krekel E. Gruner H. -W. Georgii K. -C. Buschbeck F. H. Müller E. Ühlein 《Colloid and polymer science》1959,163(1):71-79
Ohne Zusammenfassung 相似文献
519.
Ümit Çakir Mehmet Karakaplan Hamdi Temel Halil Hoşgören Çakil Erk 《Journal of inclusion phenomena and macrocyclic chemistry》1996,26(1-3):21-26
Three new lariat dilactam host molecules were prepared by the reaction of triethyleneglycol dicarboxylic acid dichloride withN,N-disubstitutèd-4,7-dioxa-1,10-diazadecane precursors. The amide nitrogen pivot of such compounds are substituted with the benzyl, octyl and dodecyl groups. The complexing ability of these dilactams is displayed with a series of metal complexes of Na+, K+, Ca2+, Sr2+, Pb2+ and Ag+ ions. The structures determined are consistent with the data of1H-NMR,13C-NMR, IR spectra and elemental analyses.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995. 相似文献
520.
Summary The PGAA applications can be enhanced by using subthermal neutrons, cold neutrons at university research reactors. Only two cold neutron beam facilities were developed at the U.S. university research reactors, namely at Cornell University and the University of Texas at Austin. Both facilities used mesitylene moderator. The mesitylene moderator in the Cornell Cold Neutron Beam Facility (CNBF) was cooled by a helium cryorefrigerator via copper cold fingers to maintain the moderator below 30 K at full power reactor operation. Texas Cold Neutron Source (TCNS) also uses mesitylene moderator that is cooled by a cryorefrigerator via a neon thermosiphon. The operation of the TCNS is based on a helium cryorefrigerator, which liquefies neon gas in a 3-m long thermosiphon. The thermosiphon cools and maintains mesitylene moderator at about 30 K in a chamber. Neutrons streaming through the mesitylene chamber are moderated and thus reduce their energy to produce a cold neutron distribution. 相似文献