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Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Changzhou University (Natural Science Edition) / Changzhou Daxue Xuebao (Ziran Kexue Ban) is the property of Editorial Department of Journal of Changzhou University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Since the influence of carbon dioxide (CO2) on the dynamic interfacial tension of crude oil and aqueous solutions at the elevated temperatures and pressures is an important issue, this investigation is aimed to measure the IFT of crude oil/water, CO2, and carbonated water. The measured values reveal that the IFTs of crude oil/CO2 are decreased through the first interval, while a gradual and continuous reduction in IFT is obtained at the second interval. Although both intercepts and slopes of the first interval lines are more than the second interval for all the studied temperatures, they show a similar trend as a function of temperature. The used vanishing IFT method measurement reveals that the minimum miscibility pressure (MMP), first contact miscibility pressure, and intersection point (where the slopes of the linear curves change) of two linear equations have a linear increasing trend as temperature changes. However, this trend was not observed for the aqueous solution saturated with CO2 (i.e., carbonated water) which can be related to the difference between liquid- and gas-phase behavior as well as the formation of carbonic acid in the carbonated water process. IFT values reduced from 18.6 mN/m (@ pH = 8) to 0.3 mN/m (@ pH = 14) with an increase in pH of the aqueous solution, while miscibility conditions can be obtained for CO2 cases at pressures higher than the MMP points. Considerably higher IFT values were measured in the presence of water and carbonated water in the range of 9.1–17.5 mN/m and 12.2–17.4 mN/m, respectively. The most important feature of the CW process can be the swelling factor of crude oil due to the fact that the oil swelling of up to 40% was achieved at elevated temperature (75 °C) and pressure (4500 psi) after only1600 s. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) were developed by exploiting the photovoltaic effect to convert solar energy into electrical energy. The photoanode layer thickness significantly affects the semiconductor film's ability to carry electronic charges, adsorb sensitizing dye molecules, and lower the recombination of photo-excited electrons injected into the semiconductor. This study investigated the dependence of the zinc oxide (ZnO) photoanode thin-film thickness and the film soaking time in N719 dye on the photocurrent–voltage characteristics. The ZnO photoanode was applied to glass using the doctor blade method. The thickness was varied by changing the scotch tape layers. The ZnO-based DSSC attained an efficiency of 2.77% with three-layered photoanodes soaked in the dye for three hours, compared to a maximum efficiency of 0.68% that was achieved with three cycles using the dip-coating method in other research. The layer thickness of the ZnO photoanode and its optimal adsorption time for the dye are important parameters that determine the efficiency of the DSSC. Therefore, this work provides important insights to further improve the performance of DSSCs. [ABSTRACT FROM AUTHOR]

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The photo extraction of rubidium atoms from the bulk of a photonic crystal has been investigated. It has been found that in the case of irradiation of the crystal in the stop band where the desorbing light does not penetrate deeply, the separation of atoms occurs practically from its surface, so that the density of desorbed atoms in the cell decreases only exponentially. In the case of irradiation of the crystal outside the stop band, the bulk of the crystal is irradiated almost completely. In this connection, the exponential decrease in the density of atoms in the cell is replaced by its relatively slow reduction of diffusion nature. The bulk diffusion coefficient of rubidium atoms in the photonic crystal was measured to be 2 · 10−8 cm2/s. [ABSTRACT FROM AUTHOR]

Adsorption deformation significantly affects the seepage characteristics of coal. However, effect of sorption time on coal permeability and gas pressure has not been investigated systematically. In this study, the sorption experiment of coal samples is conducted to elaborate the importance of sorption equilibration time. Then a coupled coal deformation and gas flow model is established considering the sorption characteristic and permeability evolution. This coupled model is implemented through finite element method to analyze the effect of sorption time on coal permeability and gas pressure. The simulation results reveal that the gas pressure of the coal will change with the adsorption time. The fracture pressure maintains a high level while the matrix pressure is relatively low during the adsorption process. The sorption time has a great influence on the distribution of gas pressure. The smaller the adsorption time is, the lower the gas pressure becomes. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An experimental and statistical study was performed for the purification of hydrogen in an H/CO mixture using the PSA process with activated carbon. This process has been extensively used for the high purification of gas mixtures. Central composite design (CCD) was used for the modeling and optimization of the process, regardless of complex and time-consuming equations generally employed in the literature. The statistical analysis of models, as obtained from the CCD method, revealed that distinct second-order polynomial equations, with F-value more than 200, p-value less than 0.0001, and R-squared more than 0.9900, could predict the experimental data for purity, recovery and productivity of hydrogen. Based on the established models, as the purge-to-feed (P/F) ratio increased, the purity increased, while the recovery and productivity decreased. The recovery and productivity first increased and then decreased as adsorption time increased. Thus, the optimal condition of the PSA process was obtained using the CCD models. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cadmium sulfide (CdS) quantum dots (QDs) were adsorbed on a titanium dioxide (TiO) nanoporous film by successive ionic layer adsorption and reaction (SILAR) method with different adsorption times to study the influences of different SILAR adsorption times on CdS quantum dot-sensitized solar cells (QDSCs). The optical properties of CdS sensitized TiO films were studied by scanning electron microscopy and UV-Vis absorbance spectroscopy. The particle size of the CdS QDs was approximated using the effective mass approximation theory from the absorbance spectra. The photovoltaic characteristics of the CdS QDSCs were analyzed by I- V characteristics and electrochemical impedance spectroscopy under air mass 1.5 illumination. As a result, the particle size of the CdS QDs became larger and light harvesting was enhanced with increasing SILAR adsorption time. The maximum photovoltaic conversion efficiency of the CdS QDSCs (1.86%) was obtained at the SILAR adsorption time of 30 min with the highest short circuit current density and lowest charge transfer resistance. [ABSTRACT FROM AUTHOR]

Abstract: The desorption characteristics of coalbed in China are affected by many factors. The desorption ratio of coalbed gas is approximately 40%, and mostly less than 70%, and it is affected by gas content and coalbed pressure. Most of the desorption time values are between 0.1883 and 19.17d, and the time span of high-rank coal is the highest, which can reach 30 d. The value has a positive correlation with coal rank. A great number of experimental data show that temperature, coal dimension and shape, coal rank, ash content, gas content, cleat, sediment environment, and coal style are the main factors affecting desorption time. According to the numerical simulation result, coal desorption volume affects the single well production. And the single well output has a positive correlation with the desorption. The variation of coal desorption time value can induce the change of output peak value of a single well and its occurrence time. [Copyright &y& Elsevier]

An experimental and theoretical study is performed for bulk separation of H/CO mixture (70/30 volume %) by PSA process with zeolite 5A, a process widely used commercially in conjunction with the catalytic steam reforming of natural gas or naphtha. For the optimized adsorption conditions of PSA, the characteristics of adsorption/desorption characteristics have been studied through breakthrough and desorption experiments under various conditions. The purge-to-feed ratio is important to the H product purity only at a long adsorption step time. H could be concentrated from 70% in the feed to 99.99% at H recovery of 67.5%. The results of all five steps in PSA are successfully predicted by the LDF model considering an energy balance and nonlinear isotherm. For the model, the effective diffusivities (D,) are obtained separately from the uptake curves of H and CO. The Langmuir-Freundlich isotherm is used to correlate the experimental equilibrium data and is very well fitted to the results. [ABSTRACT FROM AUTHOR]