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41.
Clare Robinson D.A. Barry Irina Kouznetsova 《The Science of the total environment》2009,407(16):4560-4573
Enhanced reductive dehalogenation is an attractive treatment technology for in situ remediation of chlorinated solvent DNAPL source areas. Reductive dehalogenation is an acid-forming process with hydrochloric acid and also organic acids from fermentation of the electron donors typically building up in the source zone during remediation. This can lead to groundwater acidification thereby inhibiting the activity of dehalogenating microorganisms. Where the soils' natural buffering capacity is likely to be exceeded, the addition of an external source of alkalinity is needed to ensure sustained dehalogenation. To assist in the design of bioremediation systems, an abiotic geochemical model was developed to provide insight into the processes influencing the groundwater acidity as dehalogenation proceeds, and to predict the amount of bicarbonate required to maintain the pH at a suitable level for dehalogenating bacteria (i.e., > 6.5). The model accounts for the amount of chlorinated solvent degraded, site water chemistry, electron donor, alternative terminal electron-accepting processes, gas release and soil mineralogy. While calcite and iron oxides were shown to be the key minerals influencing the soil's buffering capacity, for the extensive dehalogenation likely to occur in a DNAPL source zone, significant bicarbonate addition may be necessary even in soils that are naturally well buffered. Results indicated that the bicarbonate requirement strongly depends on the electron donor used and availability of competing electron acceptors (e.g., sulfate, iron (III)). Based on understanding gained from this model, a simplified model was developed for calculating a preliminary design estimate of the bicarbonate addition required to control the pH for user-specified operating conditions. 相似文献
42.
Relevance of the acid–base approach in prediction of adhesion properties in two‐component injection moulding 下载免费PDF全文
Eduard Kraus Sonja Horvat Christian Deubel Christian Staudigel Benjamin Baudrit Peter Heidemeyer Martin Bastian Irina Starostina Oleg Stoyanov 《应用聚合物科学杂志》2016,133(8)
We demonstrate the use of innovative wetting method in prediction of the adhesion properties of biobased polymers for two‐component injection moulding, taking into account the acid–base surface properties of joined materials. The measurements were carried out in accordance with modified Berger method by calculation of the difference in shortened acidity parameter ΔDshort between hard and soft component. Correlation factors up to 0.99 were observed between ΔDshort and peel force. In comparison to results obtained by conventional wetting methods, high potential for the selection of components with high interface adhesion and for prediction of the functionality by the acid–base approach was demonstrated. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43048. 相似文献
43.
Irina V. Nefedova Alexander G. Martynov Alexey A. Averin Gayane A. Kirakosyan Aslan Yu. Tsivadze Yulia G. Gorbunova 《Israel journal of chemistry》2016,56(2-3):181-187
Octopus-like zinc and magnesium phthalocyaninates bearing eight flexible benzylated diethylene glycol chains were synthesized and their interaction with fullerenes C60 and C70 was investigated by UV-Vis spectrophotometric titration, as well as by steady-state and time-resolved fluorescence spectroscopy in chloroform and toluene media. These measurements revealed a high affinity of receptors for C60 and C70, with selectivity to C70: binding constants for C70 are almost two times higher than for C60. These results are interpreted by means of quantum-chemical calculations using the PM6-DH2 Hamiltonian. The binding constants also depend on both the nature of the metal ion in the receptor and the solvent. It is expected that the obtained molecules and supramolecular complexes can be used for further elaboration of optoelectronic donor-acceptor materials. 相似文献
44.
45.
Manabu Nishijima Irina D. Gocheva Shigeto Okada Takayuki Doi Jun-ichi Yamaki Tetsuaki Nishida 《Journal of power sources》2009,190(2):558-562
Fluorine compounds have high discharge voltage due to its highly ionic metal-ligand bonds. In them, perovskite-type metal trifluorides with corner sharing matrix have large bottlenecks of diffusion pathways for intercalants. Iron trifluoride composites (FeF3-C) prepared by planetary ball milling with carbon showed reversible charge/discharge behavior not only for Li, but also for Na anodes. X-ray diffraction and 57Fe Mössbauer spectroscopy were applied to characterize the electrochemical properties of FeF3 vs. Li and Na anodes. The cathode performances of the other commercially available transition metal trifluorides such as MF3 (M = Ti, V, Mn, Co) have been also investigated. 相似文献
46.
Succinic acid has been pertracted with TOA using free liquid membranes without or with 1‐octanol. The addition of the alcohol led to the increase of up to 2.8–3 times of the acid's initial and final mass flows. At the same time, the influence of 1‐octanol on the transport capacity of the pertraction system was negative, its addition inducing the accumulation of succinic acid into the liquid membrane. A mathematical model describing the acid accumulation inside the liquid membrane has been developed for pertraction systems without and with 1‐octanol and offers good concordance with the experimental data. © 2012 Canadian Society for Chemical Engineering 相似文献
47.
Rheological properties of liquid explosives are summarized and discussed in this paper. Liquid explosives are highly concentrated emulsions by their physical nature. During the internal phase, it is an aqueous supersaturated solution of mainly ammonium nitrate which is a useful component of a multi-component system, and at the continuous phase it is a solution of emulsifier in hydrocarbon oils. Liquid explosives demonstrate a complex set of properties characteristic for highly concentrated emulsions, such as visco-plasticity, existence of the yield stress, thixotropy (or time-dependent behavior), non-Newtonian flow at stresses exceeding the yield stress. Rheological properties depend on the concentration of internal phase, size of droplets, and the nature of the used surfactant. Stability of these materials is determined mainly by the tendency of an aqueous solution to crystallization at prolonged storage, though shearing does not influence on phase separation. Wall slip is absent in flow of liquid emulsions through tubes. Therefore, it allows us to make reliable predictions on the output vs. pressure dependence for real technological practice. 相似文献
48.
Victor V. Ivanov Sergei D. Kirik Alexander А. Shubin Irina A. Blokhina Victor M. Denisov Lilya А. Irtugo 《Ceramics International》2013,39(4):3843-3848
A saturated acidic aluminum chloride solution with a total composition of AlCl3·HCl·12H2O was obtained, and its behavior under thermal treatments was studied using thermogravimetry, differential scanning calorimetry and mass spectrometry techniques. The thermolysis solid products were characterized with XRD and SEM. Four stages of the thermolysis could be distinguished. Initially, the solution lost free water molecules, and an amorphous precipitate with an approximate composition AlCl3·HCl·12 H2O was obtained as a product. The precipitate released eight water molecules in the temperature range 390–425 K. Then, all chlorine atoms in the form of HCl and two water molecules were outgassed at 425–485 K. The product completely lost water up to 650 K. The crystallization of the solid begins with appearance of the phase γ-Al2O3 at 1073 K, and the final product, α-Al2O3, is observed at 1323 K. The application of the saturated trichloride solutions as a binder and a promoter for activated sintering of composite ceramics on the base of alumina was examined. 相似文献
49.
Nicoleta Preda Monica Enculescu Irina Zgura Marcela Socol Elena Matei Violeta Vasilache Ionut Enculescu 《Materials Chemistry and Physics》2013
Cotton fabrics were coated with arrays of ZnO hexagonal prisms using an electroless (catalytic/autocatalytic) deposition process. A typical three step method, similar to those used for electroless deposition of metals on insulating substrates, consisting of pre-activation, activation and deposition steps was employed. The low-dimensional ZnO particles were grown from an aqueous solution containing zinc nitrate as source of zinc ions and dimethylamineborane as reducing agent. The as-obtained ZnO-coated cotton fabrics were characterized from the point of view of structure by X-ray diffraction (XRD) and morphology by scanning electron microscopy (SEM). The XRD studies demonstrate that the ZnO particles have a hexagonal wurtzite crystalline structure. The SEM observations prove that the cotton fibers are homogeneously covered by hexagonal prisms which have uniform base size of approximately 500 nm and height of 1 μm. Optical spectroscopy measurements show that the functionalization with ZnO strongly decreases the transmittance in the UV–vis region of the cotton fabrics. An important characteristic is that the ZnO-functionalized cotton fabrics exhibit superhydrophobicity, with water contact angles exceeding 150°. The technique described is highly reproducible, easy scalable and cheap, allowing a wide range of applications. 相似文献
50.
Anastasiya N. Mikhailova Galina P. Kayukova Igor P. Kosachev Irina I. Vandyukova Alexey V. Vakhin Georgy A. Batalin 《Petroleum Science and Technology》2018,36(17):1382-1388
Character of conversion of organic matter from Domanic rocks of Pervomaiskoye field (Tatarstan) of Semiluki horizon of upper Devonian deposits in the hydrothermal-catalytic system at temperature of 300?°C in carbon dioxide medium was studied with the application of complex of oil-soluble precursors of catalysts containing Fe, Co, and Cu. In presence of catalysts complex, content of organic extract increases, in which content of hydrocarbon fractions, saturated and aromatic hydrocarbons, increases 1.5 times, while resins content decreases by two times. As result of kerogen destruction in products of experiments, the content of asphaltenes and carbonaceous substances such as carbenes and carboides increase. 相似文献