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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   
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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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Polyethylene terephthalate (PET) is the most widely used polymer in the world. For the first time, the laser-driven integration of aluminum nanoparticles (Al NPs) into PET to realize a laser-induced graphene/Al NPs/polymer composite, which demonstrates excellent toughness and high electrical conductivity with the formation of aluminum carbide into the polymer is shown. The conductive structures show an impressive mechanical resistance against >10000 bending cycles, projectile impact, hammering, abrasion, and structural and chemical stability when in contact with different solvents (ethanol, water, and aqueous electrolytes). Devices including thermal heaters, carbon electrodes for energy storage, electrochemical and bending sensors show this technology's practical application for ultra-robust polymer electronics. This laser-based technology can be extended to integrating other nanomaterials and create hybrid graphene-based structures with excellent properties in a wide range of flexible electronics’ applications.  相似文献   
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This research reviews challenges in building sustainable relationships between the parties involved in the crowdfunding and crowdsourcing projects, which are running in extreme situations, such as the COVID-19 pandemic. This study aims to solve problems that generate the crowdsourcing concerns and to find better alternatives to increase trust for crowdfunding among donors, as this impacts their strategic sustainability in the conditions of turbulence and COVID-induced financial crisis. It was found that factors influence donor decisions in different ways, yet the common tendency for donor activity is non-monotonicity. Future development in the field of sustainable relationships should focus on creating a donor classification system.

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The effect of the electrostatic field on hydrogen absorption is experimentally studied for the case of AB5-type intermetallic compound LaNi4.4Al0.3Fe0.3 with low equilibrium pressure. Experimental facility contained control and measurement system for PCT-isotherms and a non-conductive polymer vessel immersed in a bath of a thermostat with transformer oil. The test sample with 100 g of the activated alloy powder was used. Electrostatic field was created between a copper tube, which simultaneously served as a hydrogen inlet, connected to a high voltage source and a grounded nickel plate rolled in the form of a cylinder around the outer wall of the vessel. The electrodes were arranged coaxially, the maximum voltage on the internal electrode was 15 kV. The high voltage source also allowed changing the polarity on the internal electrode.It was found that the electrostatic field had no effect on the already established equilibrium in the hydrogen-alloy system at a voltage at the electrode up to 15 kV, regardless of the polarity. However, the process of hydrogen absorption is noticeably slowed down when a voltage of up to 15 kV with negative polarity is applied to the internal electrode, and the effect increases with increasing voltage. At a voltage of 15 kV and the positive polarity of the internal electrode, there was no noticeable effect on the hydrogen absorption process.  相似文献   
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The process of two-wave photopolymerization of a UV-curable composition with an optically degrading inhibitor is considered. By numerical simulation, it is shown that in the composition layer uniformly exposed to UV-radiation, such systems allow getting segments with different conversion under the action of inhomogeneous visible light. Based on the data on the photopolymerization kinetics of the compositions from triethylene glycol dimethacrylate (TEGDMA) and bisphenol-A glycidyl dimethacrylate (bis-GMA) with the UV-initiator 2,2-dimethoxy-2-phenylacetophenone (DMPA), it was shown that 3,5-di-tert-butyl-o-benzoquinone (35Q) with N,N-dimethylaniline (DMA, “Aldrich”, 99%) can serve as an inhibitor that degrades under action of visible radiation. Combining inhomogeneous visible light generated with a conventional DLP-projector and uniform UV-radiation of LED (365 nm) the two-wave lithographic process was implemented to create polymeric 2D-structures in 20 μm layer of the compositions from TEGDMA (70)/bis-GMA (30)/DMPA (0.05 wt%)/35Q (0.5 wt%)/DMA (1 wt%).  相似文献   
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The production of printed circuit boards using the printing process produces considerable quantities of copper-containing etching solutions. The copper is recovered from the ammoniacal etching baths by cementation with aluminum waste at ≥ 99 % Cu yield rates. Instead of the usual landfilling, the aluminum-containing solution is processed into a coagulant which can be used in the treatment of mining tailings and wastewater. The aluminum oxychloride produced in this way was characterized in detail and its effectiveness as a flocculant for a finely dispersed system (kaolin suspension) was investigated and confirmed in a jar test.  相似文献   
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