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Anastasia A. Ivanova Chi Phan Ahmed Barifcani Stefan Iglauer Alexey N. Cheremisin 《Journal of surfactants and detergents》2020,23(2):327-338
Surfactant flooding has widely been used as one of the chemically enhanced oil recovery (EOR) techniques. Surfactants majorly influence the interfacial tension, γ, between oil and brine phase and control capillary number and relative permeability behavior and, thus, influence ultimate recovery. Additives, such as nanoparticles, are known to affect surfactant properties and are regarded as promising EOR agents. However, their detailed interactions with surfactants are not well understood. Thus, in this work, we examined the influence of silica nanoparticles on the ability of surfactants to lower γ and to increase viscosity at various temperatures and salinities. Results show that the presence of nanoparticles decreased γ between n-decane and various surfactant formulations by up to 20%. It was found that γ of nanoparticles–surfactant solutions passed through a minimum at 35 °C when salt was added. Furthermore, the viscosity of cationic surfactant solutions increased at specific salt (1.5 wt.%) and nanoparticle (0.05 wt.%) concentrations. Results illustrate that selected nanoparticles–surfactant formulations appear very promising for EOR as they can lower brine/n-decane interfacial tension and act as viscosity modifiers of the injected fluids. 相似文献
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Galin Ivanov Ertugrul Bilgucu Ivelina Ivanova Milena Dimitrova 《International Journal of Dairy Technology》2020,73(3):563-569
The present study aimed to investigate the effect of somatic cell count (SCC) of raw cow's milk on the volatile organic compound (VOC) profiles of yoghurt. Test yoghurt samples were produced from three batches of cow's milk with low, medium and high SCC, respectively. The VOCs were determined by gas chromatography–mass spectrometry (GC–MS) analysis. A lower diacetyl and acetoin content and a higher content of 2‐heptanone, and butanoic and hexanoic acids were established in the yoghurt samples from batches with high SCC of above 1 000 000 cells/cm3. The increased SCC of cow's milk had a negative effect on the volatile organic compound profiles of yoghurt. 相似文献
5.
Felix Rivkin Irina Kuznetsova Nadezhda Ivanova Sergey Suhodolsky 《Soil Mechanics and Foundation Engineering》2002,39(1):42-43
Soil Mechanics and Foundation Engineering - 相似文献
6.
S. V. Ivanova 《Materials Science》2007,43(5):718-724
We have established that technological defects (cracks) in zirconium articles can develop in the course of long-term storage
prior to their mounting in a reactor, which is caused by the action of residual stresses and hydrogen. We have considered
the conditions of after-operation storage of zirconium articles of the fuel core of thermal reactors in water of the cooling
ponds of reactors and in spent-fuel storehouses. The possibility of subsequent hydrogenation of these articles during their
storage has been shown. Finally, we have studied the effect of hydrogen, absorbed in the course of storage, on the crack resistance
of zirconium articles and the development of defects in them due to delayed hydride cracking.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 105–109, September–October, 2007. 相似文献
7.
Valentina I. Simagina Pavel A. Storozhenko Olga V. Netskina Oksana V. Komova Galina V. Odegova Yury V. Larichev Arcady V. Ishchenko Anna M. Ozerova 《Catalysis Today》2008,138(3-4):253
Catalytic hydrolysis of NaBH4 and NH3BH3 has been studied. It was shown that the nature of the support and the active component of the catalyst affect the H2 generation rate. Despite similar sizes of rhodium particles formed on the surface of different supports (γ-Al2O3, TiO2, carbon), their reactivity is different. Rh/TiO2 with low rhodium concentration (1 wt.%) is the most active catalyst both in the hydrolysis of NaBH4 and NH3BH3. The obtained results show that the rhodium chloride interaction with titania determines the reactivity of rhodium particles formed under action of NaBH4 medium. TEM, DRS UV–vis and XPS were used to characterize the catalysts. 相似文献
8.
Tkachenko Yurii G. Britun Yurchenko Djema Z. Ochkas Larisa F. Bovkun Galina A. 《Powder Metallurgy and Metal Ceramics》2004,43(1-2):99-104
The influence which the composition of powder mixtures, the treatment conditions which the mixtures are subjected to, and the conditions under which the hot-pressed composite materials B4C – (5-10 mass%) calcium-silicon are fabricated exert on the structure, nature of failure, and mechanical properties of these materials is investigated. Optimum properties are possessed by material containing 10 mass% of addition. It is shown that the structure, morphology, and dispersivity, as well as the nature of the distribution of the components that are added to the composite material (secondary phase) vary as the temperature of hot pressing changes. Maximal mechanical characteristics of the composite material (σbend = 560 MPa, K 1c = 4.7 MPa·m1/2, HV = 37 GPa) are attained at hot-pressing temperatures in the range 2000-2100°C. 相似文献
9.
Tarter Ralph E.; Kirisci Levent; Kirillova Galina P.; Gavaler Judy; Giancola Peter; Vanyukov Michael M. 《Canadian Metallurgical Quarterly》2007,21(4):462
This investigation determined the influence of testosterone and neurobehavioral disinhibition (ND) on risk for substance use disorder (SUD). Testosterone level during puberty was hypothesized to promote social dominance associated with norm-violating behavior that, in turn, predisposes individuals to use of illicit drugs and, subsequently, SUD. Using a prospective paradigm, the authors recruited 179 boys (mean age=11.62 years, SD=0.88) and followed up when participants were ages 12-14, 16, 19, and 22. Results indicated that social dominance/norm-violating behavior (SD/NVB) at age 16 mediated the association between testosterone level (ages 12-14) and SUD (age 22). In addition, SD/NVB mediated the association between ND and SUD. These findings suggest that development of SUD is influenced by androgen-dependent and neurobehavioral processes via a social motivational style characterized by SD/NVB. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Z Dimitrova Dimitrova VG Dumanov G Ivanova Petrova 《Canadian Metallurgical Quarterly》1997,67(2-3):73-79
Registered psychiatric morbidity in Bulgaria as a whole and particularly in Plovdiv, the second largest region of the country, was assessed. Three aspects of psychotropic drug usage were analysed, namely, changes in registered psychotropic drugs, the prescribed daily dose (PDD) values for 2 years, and the preferred therapeutic schemes, and drug usage and needs in a psychiatric hospital with 365 beds. This was done by time series analysis for evaluation of psychiatric morbidity and drug consumption data, calculation of PDD for psychotropic medicines, and, based on a modification of the World Health Organization's morbidity method, assessment and prediction of drug use and needs in Plovdiv hospital. The results indicated that the registered morbidity had increased by 4% over the period 1989-93 to 2,427 psychiatric patients per 100,000 people. The increased consumption of especially benzodiazepines and sedative medicines was analyzed. Diazepam was prescribed the most often (91.1%), followed by levomepromazine (86.4%), haloperidol (82.7%), etc. Future drug consumption in Plovdiv hospital is expected to decrease because therapeutic practice in hospitals has been revised and improved on the basis of the World Health Organization's recommendations. 相似文献