Mcdonaldlevesque8126

Shale gas is a promising energy source offering additional energy security over concerns of fossil fuel depletion. Injecting CO2 into depleted shale gas reservoirs might provide a feasible solution for CO2 storage and enhanced gas recovery. However, shale strain caused by the CO2 injection as well as CO2 sequestration in the reservoir needs to be considered during shale gas production. For this purpose, this paper examines the adsorption capacities, CO2-induced swelling, and He-induced strain of shales at 0-16 MPa and 35-75 °C. The maximum excess adsorption at different temperatures correlated with the bulk phase density as the CO2 temperature increased, the maximum excess adsorption density decreased. The density of the adsorbed phase, obtained using the Dubinin-Radushkevich model, was used to fit the excess adsorption data. At low pressure, the CO2-induced strain on shale was caused by the gas adsorption, whereas at high pressure, it was caused by gas pressure. The absolute adsorption linearly correlated with the adsorption-induced strain.The acid base protonation equilibria of N-acetylcysteine (Nac) and its equilibrium constants in water solutions were determined by the Hyperquad 2008 software assessment from the pH potentiometry data, which provides a diversity of statistics presentations. The effect of a number of organic solvents on the acid base protonation processes was also examined. The solution equilibria of N-acetylcysteine (Nac) were studied at T = 298.15 K in water (w1) + organic liquid mixtures [100 w2 = 0, 20, 40, 60, and 80%] with an ionic strength of I = 0.16 mol·dm-3 NaNO3. Also, the organic solvent's influence was studied based on the Kamlet-Taft linear solvation energy relationship. The experimental results were compared with theoretical ones obtained via the Gaussian 09 calculation computer program. The protonation equilibria of Nac were found to be important in the progress of separation systems in aqueous and non-aqueous ionic solutions. Nac showed a likely good metal dibasic chelating bioligand as the DFT calculations proved two binding sites. Spectrophotometry evaluation was also done for N-acetylcysteine bioligands at various pH values in water solutions then its absorbance ratio was measured.Steam injection is the most widely used technique for effectively reducing the viscosity of heavy oil in heavy oil production, in which in situ upgrading of heavy oil by aquathermolysis plays an important role. Earlier, transition-metal catalysts have been used for improving the efficiency of steam injection by catalytic aquathermolysis and achieving a higher degree of in situ oil upgrading. However, the unclear mechanism of aquathermolysis makes it difficult to choose efficient catalysts for different types of heavy oil. This theoretical study is aimed at deeply understanding the mechanism of in situ upgrading of sulfur-containing heavy oil and its catalysis. For this purpose, cyclohexyl phenyl sulfide (CPS) is selected as a model compound of sulfur-containing oil components, and, for the first time, a catalytic effect of transition metals on the thermochemistry and kinetics of its aquathermolysis is investigated by the density functional theory (DFT) methods with the use of the Becke three-parameter Lee-Yanrmolysis provides a new supplementary theoretical tool that can be used in the development of catalysts for different chemical transformations of heavy oil components in reservoirs due to hydrothermal treatment.Biomass tar is the bottleneck of biomass gasification, which not only is adverse to energy production but also brings severe environmental issues. A scrubber with vegetable oil is considered as a low-cost but efficient approach for tar removal, but the effects of oil's properties on different tar absorptions were rarely reported. In this study, canola oil, palm oil, and pure oleic acid and linoleic acid, which are the main compounds of vegetable oils, were employed for absorptive removal of benzene, toluene, and phenol. The degree of unsaturation, average molecular weight, and average chain length of solvents were quantitatively characterized. A series of time and temperature-dependent absorption experiments were conducted, and the relationship between oils' properties and absorption performances was built. Results showed that pure oleic acid had the biggest absorption capacity for benzene and toluene due to the mono-unsaturated structure. Increasing the average molecular weight and chain length also enhanced tar absorption. Moreover, Grey relative analysis was employed to investigate the influence of each factor on tar absorption. #link# The average molecular weight exerted the most significant influence on tar absorption in the tested temperature range whose comprehensive relevance coefficients reached the highest at 0.9810, 0.7669, and 0.7739 for benzene, toluene, and phenol, respectively. This study puts more attention on the nature of vegetable oils, and we hope to provide useful information for modulating a better oil-based scrubber medium and further enhancing tar absorptive removal.Coalbed is the carrier for coalbed methane (CBM) enrichment and migration. The pore structure characteristics of coal and their main geological controlling factors are critical to the exploration and development of CBM. In this paper, 20 coal samples were collected from eastern Yunnan and western Guizhou, China. Based on vitrinite reflectance, proximate analysis, maceral analysis, and low-temperature N2 adsorption/desorption (LT-N2GA) experiments, the hysteresis coefficient of low-temperature N2 desorption was proposed, the types of pore structure were identified, and the effects of coal facies and rank on the pore structure were revealed. The results show that the Ro,max values of the 20 coal samples are between 0.74 and 3.38%, which belong to medium- and high-rank coal. In the coal macerals, the vitrinite is mainly collodetrinite. The inertinite is dominated by semifusinite, and some coal samples contain exinite. link2 The coal samples investigated can be divided into two types. Type A samples mainly contain openin controlling factor of the pore structure of type A coal samples, while the pore structure of type B coal samples are jointly controlled by TPI and coal rank. Type B coal samples are mainly located in Zhuzang and Laochang high-rank coal research areas, while the distribution of type A coal samples is mainly in other medium-high-rank coal research areas. These results will contribute to the exploration and development of CBM and also guide the study of pore structures of other unconventional gas reservoirs.Prior studies have shown that trifluoromethylarenes can be labeled in high molar activities (Am > 200 GBq/μmol) with positron-emitting carbon-11 (t1/2 = 20.4 min) by the reaction of the copper(I) derivative of [11C]fluoroform [11C]CuCF3, with several types of precursors, such as aryl iodides, arylboronic acids, and aryldiazonium salts. Nonetheless, these precursors can be challenging to synthesize, and in the case of diazonium salts, are unstable. Methods that reduce challenges in precursor preparation for the synthesis of [11C]trifluoromethylarenes are desirable to enhance possibilities for developing biologically relevant 11C-labeled compounds as radiotracers for biomedical imaging with positron emission tomography (PET). Here, we explored the production of no-carrier-added [11C]trifluoromethylarenes from commercially available primary aromatic amines through reactions of [11C]CuCF3 with diazonium salts that were generated in situ. Moderate to high isolated decay-corrected radiochemical yields (RCY) (32-84%) were obtained rapidly (within 2 min) for many para-substituted and meta-substituted primary aromatic amines bearing a halo, methoxy, thiomethyl, hydroxy, nitro, nitrile, carboxyl, ethylcarboxy, or trifluoromethyl substituent. link3 Null to low RCYs (0-13%) were observed only for ortho bromo-, nitro-, or nitrile-substituted precursors. This new radiosynthetic method usefully expands options for producing PET radiotracers bearing a [11C]trifluoromethyl group, especially from aryl amine precursors.Dewaxed honeycomb powder (HCP) was used as a promising adsorbent for removal of malachite green (MG) from aqueous solution. Raw honeycomb was strategically dewaxed by petroleum ether, and the purified product was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), pHzpc, and proximate analysis. A high uptake capacity (123 mg/g) was found at neutral pH. Experimental data follow pseudo-second-order kinetics (k2 as 0.45 × 10-2 g/min/mg, R2 = 0.986) and Langmuir isotherm with R2 0.999. Thermodynamic parameters suggested a spontaneous (ΔG = -26.28 kJ/mol) and exothermic (ΔH = -11.61 kJ/mol) process, which suggests increased randomness (ΔS = 0.0486 kJ/mol) at the solid-liquid interface during the adsorption process. The material can be regenerated by ordinary salt solution (1 M NaCl) and efficiently reused for three cycles with a minimal loss in efficiency. Adsorption mechanism is proposed to be a combination of electrostatic interaction and π-π stacking between aromatic units of HCP and MG. selleck products , possibility of wax commercialization, economic sustainability, and comprehensive waste management make HCP an ideal choice for dye decolorization.A liquid cathode glow discharge (LCGD) was developed as a low-power and miniaturized excitation source of atomic emission spectrometry (AES) for the determination of K, Na, Ca, and Mg in water samples from rivers and lakes. The discharge stability and parameter influencing the analytical performance of LCGD-AES were systematically examined. Moreover, the measurement results of water samples using LCGD-AES were verified by ion chromatography (IC). The results showed that the optimized operating parameters are a 660 V discharge voltage, pH = 1.0 HNO3 as the supporting electrolyte, and a 4.0 mL min-1 solution flow rate. High concentrations of some metals may interfere with the detection of Ca and Mg. Low-molecular-weight organic substances do not have a remarkable enhancement on signal intensity. With the addition of 0.5% cetyltrimethylammonium chloride (CTAC), the emission intensity of elements can enhance significantly. However, it is not used to further evaluate the analytical performance due to instability of plasma after adding CTAC. The maximum power of LCGD is 52 W. The limits of detection and precision (RSD, in 1 mg L-1) of K, Na, Ca, and Mg are 0.20, 0.02, 0.01, and 0.01 mg L-1 and 0.9, 1.5, 0.6, and 1.2%, respectively. The measurement results of K, Na, Ca, and Mg in water samples by LCGD-AES are basically in agreement with the reference values measured by IC. The recovery of samples ranged from 84 to 113% except for Na, suggesting that the measurement results have high accuracy and reliability. All the results indicated that the LCGD-AES can provide an alternative analytical method for in situ, real-time, on-line determination of K, Na, Ca, and Mg in water samples from rivers and lakes.The stator and rotor of an all-metal screw pump are made of metal; so the matching method of the all-metal screw pump cannot be like that of the traditional rubber screw pump, and a certain gap must be reserved. If the gap is too small, it will affect the normal operation of the pump. If the gap is too large, the pump leakage will also become larger, affecting the efficiency of the pump. In this paper, the method of numerical simulation is used to optimize the gap of the pump. At the same time, it is found that the optimal gap of the pump is closely related to the viscosity of the fluid transported by the pump, and different viscosity fluids have different optimal speeds. The speed and clearance of the pump are optimized through numerical simulation to ensure high pump efficiency while taking into account energy saving and avoid the waste caused by excessively high speed. Finally, the relevant research results of numerical simulation are verified through experiments, and it is found that the experimental results are in good agreement with the simulation results, which also proves the accuracy of the numerical simulation results.