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61.
Eva Kuzielová Matúš Žemlička Jiří Másilko Martin T. Palou 《Journal of Thermal Analysis and Calorimetry》2018,133(1):63-76
Stability of Dyckerhoff cement Class G partially substituted (15 mass%) by metakaolin (MK), silica fume (SF) and ground granulated blast-furnace slag (BFS) was investigated after 7 days of curing under standard and two different autoclaving conditions. Mercury intrusion porosimetry, X-ray diffraction analysis and combined thermogravimetric–differential scanning calorimetry were used to evaluate pore structure development, compressive strength and their dependence on the type of additives in relation to the particular phase composition. Hydrothermal curing led to the formation of α-C2SH and jaffeite, mostly in the case of referential samples and compositions with addition of slowly reacting BFS. Whilst modest hydrothermal curing (0.6 MPa, 165 °C) favoured formation of α-C2SH, larger amounts of jaffeite were determined after curing at the highest used pressure and temperature (2.0 MPa, 220 °C). Undesired transformation of primary hydration products was prevented especially by addition of highly reactive and very fine SF. Particular composition attained the best pore structure characteristics and compressive strength after curing at 0.6 MPa and 165 °C. Formation of more stable phases with C/S ratio close to 1 was proved by wollastonite formation during DSC analyses. More severe conditions of curing, however, led to the significant deterioration of microstructure and strength of corresponding sample, probably due to the formation of trabzonite, killalaite and zoisite. Considering the values of hydraulic permeability coefficient and compressive strength, replacement of cement by MK improved significantly the properties of cement when compared with the referential as well as with other blended compositions under the mentioned curing conditions. 相似文献
62.
The paper shows a computer-assisted procedure for the optimization of selectivity of two columns coupled in series by tuning the working temperature (using the isothermal mode) and columns coupling-point pressure at constant inlet and outlet carrier gas pressures. The optimization procedure validation was tested by the separation of 32 hydrocarbons in a column series with the aim to resolve the maximum number of components in the shortest possible analysis time.Dedicated to Professor J. F. K. Huber on the occasion of his 65th birthday 相似文献
63.
Andreas Hofer Eva Brosche und Rudolf Heidinger 《Fresenius' Journal of Analytical Chemistry》1971,253(2):117-119
Zusammenfassung Eine rasche und selektive Methode zur Bestimmung von wasserlöslichem Bor in Mischdüngern wird beschrieben. Bor wird aus der Probelösung, die etwa 0,1 N an Salzsäure sein soll, durch zweimaliges Schütteln mit 20%iger Lösung von 2-Äthyl-1,3-hexandiol in Methylisobutylketon isoliert. Anschließend wird es mit 0,5 N Natronlauge in die wäßrige Phase zurückgeschüttelt und mit, Azomethin H spektralphotometrisch bei 415 nm bestimmt.
Der Direktion der Österreichischen Stickstoffwerke A.G. danken wir für die Erlaubnis zur Veröffentlichung. 相似文献
Spectrophotometric determination of water-soluble boron in complex fertilizers using azomethine h following a separation by extraction with 2-ethyl-1,3-hexanediol
A rapid and selective method for the determination of water-soluble boron in complex fertilizers is described. Boron is separated from the sample solution, which should be approximately 0.1 N in hydrochloric acid, by shaking twice with 20% solution of 2-ethyl-1,3-hexanediol in hexone. Following this extraction boron is back-extracted into the aqueous phase with 0.5 N sodium hydroxide. It is finally determined spectrophotometrically at 415 nm using azomethine H as reagent.
Der Direktion der Österreichischen Stickstoffwerke A.G. danken wir für die Erlaubnis zur Veröffentlichung. 相似文献
64.
Lamed R Kenig R Morag E Yaron S Shoham Y Bayer EA 《Applied biochemistry and biotechnology》2001,90(1):67-73
Previous work from our group [Morag (Morgenstern), E., Bayer, E. A., and Lamed, R. (1991), Appl. Biochem. Biotechnol.
30, 129–136] has demonstrated an anomalous electrophoretic mobility pattern for scaffoldin, the 210-kDa cellulosome-integrating
subunit of Clostridium thermocellum. Subsequent evidence [Morag, E., Bayer, E. A., and Lamed, R. (1992), Appl. Biochem. Biotechnol.
33, 205–217] indicated that the effect could be attributed to a nonproteolytic fragmentation of the subunit into a defined series
of lowermolecular-weight bands. In the present work, a recombinant segment of the scaffoldin subunit was employed to determine
the site(s) of bond breakage. An Asp-Pro sequence within the cohesin domain was identified to be the sensitive peptide bond.
This sequence appears quite frequently in the large cellulosomal proteins, and the labile bond may be related to an as yet
undescribed physiological role in the hydrolysis of cellulose by cellulosomes. 相似文献
65.
Per Malmberg Eva Jennische Daniel Nilsson Håkan Nygren 《Analytical and bioanalytical chemistry》2011,399(8):2711-2718
The use of high-resolution, imaging TOF-SIMS is described and examples are made to demonstrate the application of the method
in medical research. Cytochemistry by TOF-SIMS is shown by localization of diacylglycerol (DG) in cryostat sections of hyaline
cartilage and by localization of corticosterone in cryostat sections of the adrenal gland cortex. Quantitative measurements
and comparison of groups is shown by comparing the lipid content of adipose tissue from two mouse strains, transgenic mouse
expressing the FOXC2 gene and wild-type controls. Finally, biopsies made for histopathological diagnosis of infantile reversible
cytochrome c oxidase deficiency myopathy were analyzed in order to define the chemical content of areas showing a pathological
structure in the light microscope. The use of high-resolution, imaging TOF-SIMS in medical research allows analysis of intact
tissue and probe-free localization of specific target molecules in cells and tissues. The TOF-SIMS analysis is not dependent
on penetration of reagents into the sample and also independent of probe reactivity such as cross-reactivity or background
staining. The TOF-SIMS method can be made quantitative and allows for analysis of specific target molecules in defined tissue
compartments. 相似文献
66.
67.
68.
Rainer Strommer Wolfgang Strauss Helmut Emmert Reinhard Sailer Rudolf Steiner Eva Reisinger Ernst Haslinger Hans W. Schramm 《Monatshefte für Chemie / Chemical Monthly》2001,132(3):387-392
Summary. Selenium dioxide oxidation allows the selective introduction of a hydroxyl group at position 6 of the steroid skeleton of
the antihormone (11β, 17β)-11-(4-dimethylamino-phenyl)-17-hydroxyl-17-(1-propynyl)-estra-4,9-dien-3-one (mifepristone, RU
486) and leads in a one-step procedure to two diastereomeric oxidation products. Their structure (6α- and 6β-hydroxy-mifepristone)
was determined by NMR spectroscopy. The antiprogestinic activity of the oxidation products is comparable to that of mifepristone.
Received August 25, 2000. Accepted (revised) October 24, 2000 相似文献
69.
Stanislav Stříteský Martin Vala Jan David Eva Šafaříková Jan Víteček Martin Weiter 《Chemical Papers》2018,72(7):1635-1643
In this paper, the possibility to use diketopyrrolopyrrole (DPP) for the construction of electrical devices designed to interact with animal cells was studied. For this purpose, the biocompatibility and electrical properties of the selected DPP derivative (3,6-bis(5-(benzofuran-2-yl)thiophen-2-yl)-2,5-bis(2-ethyl-hexyl)pyrrolo[3,4-c]pyrrole-1,4-dione) [referred as DPP(TBFu)2] were researched. The electrical properties were studied using model organic field-effect transistors. Mainly investigated was under what conditions maximum charge carrier mobility can be achieved. Using the cumulative effect of self-assembled monolayers on dielectrics and electrodes and detailed thermal analysis of the DPP, a higher charge carrier mobility was achieved than has been previously reported (5.5?×?10?3 cm2 V?1 s?1). The biocompatibility was studied based on a culture of 3T3 fibroblasts. This research revealed that DPP(TBFu)2 can be used in applications involving direct contact with living animal cells. The conclusions found with these model devices can be applied to components suitable for biosensing applications, e.g., water- or electrolyte-gated organic field-effect transistors. 相似文献
70.
Access to the Bis‐benzene Cobalt(I) Sandwich Cation and its Derivatives: Synthons for a “Naked” Cobalt(I) Source? 下载免费PDF全文
Stefan C. Meier Albina Holz Jan Kulenkampff Alexei Schmidt Dr. Daniel Kratzert Dr. Daniel Himmel Dominik Schmitz Dr. Ernst‐Wilhelm Scheidt Prof. Dr. Wolfgang Scherer Dr. Christine Bülow Martin Timm Dr. Rebecka Lindblad Dr. Scott T. Akin Dr. Vicente Zamudio‐Bayer Prof. Dr. Bernd von Issendorff Prof. Dr. Michael A. Duncan Prof. Dr. J. Tobias Lau Prof. Dr. Ingo Krossing 《Angewandte Chemie (International ed. in English)》2018,57(30):9310-9314
The synthesis and structural characterization of the hitherto unknown parent Co(bz)2+ (bz=benzene) complex and several of its derivatives are described. Their synthesis starts either from a CoCO5+ salt, or directly from Co2(CO)8 and a Ag+ salt. Stability and solubility of these complexes was achieved by using the weakly coordinating anions (WCAs) [Al(ORF)4]? and [F{Al(ORF)3}2]? {RF=C(CF3)3} and the solvent ortho‐difluorobenzene (o‐DFB). The magnetic properties of Co(bz)2+ were measured and compared in the condensed and gas phases. The weakly bound Co(o‐dfb)2+ salts are of particular interest for the preparation of further CoI salts, for example, the structurally characterized low‐coordinate 12 valence electron Co(PtBu3)2+ and Co(NHC)2+ salts. 相似文献