Mcphersonsalisbury4898

Z Iurium Wiki

Oxidative coupling of methane (OCM) is a reaction to directly convert methane into high value-added hydrocarbons (C2+) such as ethylene and ethane using molecular oxygen and a catalyst. This work investigated lanthanum oxide catalysts for OCM, which were promoted with alkaline-earth metal oxides (Mg, Ca, Sr, and Ba) and prepared by the solution-mixing method. The synthesized catalysts were characterized using X-ray powder diffraction, CO2-programmed desorption, and X-ray photoelectron spectroscopy. The comparative performance of each promoter showed that promising lanthanum-loaded alkaline-earth metal oxide catalysts were La-Sr and La-Ba. In contrast, the combination of La with Ca or Mg did not lead to a clear improvement of C2+ yield. The most promising LaSr50 catalyst exhibited the highest C2+ yield of 17.2%, with a 56.0% C2+ selectivity and a 30.9% CH4 conversion. Catalyst characterization indicated that their activity was strongly associated with moderate basic sites and surface-adsorbed oxygen species of O2 -. Moreover, the catalyst was stable over 25 h at a reactor temperature of 700 °C.This study concentrates on the analysis of the oil and natural gas reserves of Iran, which hold a crucial role in the global energy market. A common method for the analysis and prediction of the production rates of nonrenewable reserves is used, namely, the Hubbert peak theory. The corresponding curves shed light on the energy policy and future guidelines of the region. Interestingly, Iran ranks fourth and second in the world's oil and natural gas reserves, and the analysis covers more than 50 years, which makes it beneficial in different ways. Regional production rates, the maximum amount of production, and the approximate year in which this would happen, plus the time span until all reserves entirely run out, are extracted in this assessment. Besides, the effect of local consumption on production is examined in detail. Comparisons with other key countries are given. Oil producers, Iraq and Saudi Arabia, and natural gas producers, Russia and Qatar, are considered, and the reasons behind each selection are explained. In addition, global energy policies related to pollution reduction and the effects of the downstream industries are discussed. Moreover, the impact of the international sanctions on Iran production is reviewed. Furthermore, a prediction on outlook of the future of Iran oil and natural gas production is made. Finally, the energy outlook, including the main primary energy resources for these five countries, is briefly reviewed.Catalytic reforming is a key technology in the petroleum refining and petrochemical industry. In recent years, countercurrent continuous reforming has put forward and practiced the new concept of matching the activity of the catalyst with the difficulty of the reaction. Based on the equation-oriented method, the steady-state model for the reactor-regenerator section of countercurrent continuous reforming was established, including the reactor module, the regenerator module, the compressor model, the heat exchanger model, the heating furnace model, and the oil property model. The inlet and outlet of each module are connected according to the actual technological process, and the model conforms to the requirement of real-time optimization (RTO). The sequential quadratic programming (SQP) algorithm is used for calculation in this study. The model is calibrated to make the calculated value more consistent with the actual value. The model simulation showed the trend of the reforming reaction and the difference between countercurrent reforming and cocurrent reforming. Finally, the process model was optimized for different goals such as the yield of aromatics, the yield of high-octane gasoline, and the yield of C7 + aromatics. These results indicate that the established model can simulate the actual industrial process, which can meet the requirements of RTO, and obtain considerable profits for different optimization objectives.Tight sandstone reservoirs have ultralow physical properties and strong heterogeneity, and there is a need to describe the corresponding pore structure characteristics systematically to promote research on unconventional reservoirs. The pore structure, controlled by the diagenesis and volcanic activity of the tight reservoirs in the third member of the Shahejie Formation (Es3) of the Gaoshangpu structural belt in the Nanpu Sag, is studied by high-pressure mercury injection, nuclear magnetic resonance, and constant-rate-controlled mercury porosimetry. The results show that the Es3 reservoir can be divided into three types the pore radii of Type I reservoirs range from 120 to 180 μm, and the throat radii are larger than 1 μm, resulting in good pore connectivity; pore radii of Type II reservoirs are approximately 100 μm, and the throat radii range from 0.1 to 1 μm, resulting in moderate pore connectivity; and pore radii of Type III reservoirs are much smaller than 100 μm, and the throat radii are smaller than 0.1 μm, resulting in worst pore connectivity. The pore size of Type I reservoirs is most sensitive to compaction, and the pore connectivity is mainly controlled by carbonate cementation; the pore throat size and pore connectivity of Type II reservoirs are seriously affected by clay cementation, and pores are mainly formed by dissolution. However, the pore structure of Type III reservoirs is the worst among those investigated in this study but can be further improved by dissolution to a certain extent. Volcanic activity controls cementation and affects dissolution, thus changing the pore structure. A pore structure evolution model is established, which can provide a reference for future oil gas exploration.Optically addressable spin defects in wide-band-gap semiconductors as promising systems for quantum information and sensing applications have recently attracted increased attention. Spin defects in two-dimensional materials are expected to show superiority in quantum sensing due to their atomic thickness. Here, we demonstrate that an ensemble of negatively charged boron vacancies (VB -) with good spin properties in hexagonal boron nitride (hBN) can be generated by ion implantation. We carry out optically detected magnetic resonance measurements at room temperature to characterize the spin properties of ensembles of VB - defects, showing a zero-field splitting frequency of ∼3.47 GHz. We compare the photoluminescence intensity and spin properties of VB - defects generated using different implantation parameters, such as fluence, energy, and ion species. With the use of the proper parameters, we can successfully create VB - defects with a high probability. Our results provide a simple and practicable method to create spin defects in hBN, which is of great significance for realizing integrated hBN-based devices.A cyclic depsipeptide, nobilamide I (1), along with the known peptide A-3302-B/TL-119 (2), was isolated from the saline cultivation of the marine-derived bacterium Saccharomonospora sp., strain CNQ-490. The planar structure of 1 was elucidated by interpretation of 1D and 2D NMR and MS spectroscopic data. The absolute configurations of the amino acids in 1 were assigned by using the C3 Marfey's analysis and comparing them with those of 2 based on their biosynthetic pathways. Nobilamide I (1) decreased cell motility by inhibiting epithelial-mesenchymal transition markers in A549 (lung cancer), AGS (gastric cancer), and Caco2 (colorectal cancer) cell lines. In addition, 1 modulated the expression of the matrix metalloproteinase (MMP) family (MMP2 and MMP9) in the three cell lines.Recently, the application of novel nanomaterials, especially magnetic nanomaterials in the development of latent fingerprints (LFP), has become the hot focus for forensic scientists and criminal investigators. As a type of recyclable, environment-friendly material, Fe3O4 nanoparticles achieve a wonderful effect in visualization of LFP. We first report the synthesis and encapsulation of nano-Fe3O4 through "facile coprecipitation", (3-mercaptopropyl)triethoxysilane was covalently embedded into Fe3O4 nanoparticles, and the Fe3O4 core was encapsulated by the nanosilver to prepare novel magnetic nanomaterials (P-MNP@Ag) with the core-shell configuration. For comparison, the magnetic nanomaterials (S-MNP@Ag) were prepared by surface modification. Their composition, structure, and properties were characterized by SEM, TEM, XRD, IR, XPS, and VSM. Compared with commercially available gold powder, silver powder, bare magnetic powder, and prepared S-MNP@Ag, the development effect of LFP on different objects by using P-MNP@Ag had better performance, which presented the advantages of low background interference, high sensitivity, and clear secondary details in LFP. In the crime scenes of some influential cases, P-MNP@Ag had been applied to the visualization of LFP. The biometric identification of criminal suspects was confirmed through fingerprint comparison, which was highly affirmed by the public security department.The coke reactivity index and coke strength after reaction are critical parameters for the efficient operation of a blast furnace. Therefore, maintaining desired qualities of the produced coke as per coal blend chemistry and coke oven battery parameters is essential. However, the coke reactivity index (CRI) and coke strength after reaction (CSR) vary from laboratory to laboratory even though they have the same determination methodology. In the present investigation, a unique laboratory sample holder for reactivity test has been developed. The test method by Nippon Steel Corporation (NSC) has been compared with the newly developed sample holder method. The correlation between coke CRI and CSR has been studied with samples with a wide range of reactivity in the repeatability test. Results confirmed that the reactivity of coke highly depends on the reaction of individual coke pieces participating in the test. Leptomycin B in vivo Despite undergoing strict process monitoring of the testing procedure of hot strength of coke, the present study confirmed that a variation of ±2 points in coke CSR and CRI does not affect coke quality in a single reading. The study also includes the influence of the number of coke pieces in the test sample to optimize the coke bed height. This paper described in detail the methodologies adopted, addressing the factors resulting in differences in CRI/CSR values within the same coke.The policies to meet the "zero waste" regime and transition to sustainable circular economy can no longer ignore the use of wastes in place of natural resources, and these daunting and vital societal challenges are nowadays being faced by several nations. The main objective of this work was to search waste materials suitable for a quick and environmentally friendly production of a nanoporous geomaterial able to trap toxic metals at the solid/liquid interface. More specifically, the end-of-waste from the thermal inertization of cement-asbestos and glass powder from domestic glass containers have been employed as sources for the hydrothermal synthesis of a tobermorite-rich material (TRM) successfully tested for the selective removal of Pb2+, Zn2+, Cd2+, and Ni2+ from aqueous solutions. The synthesis was carried out in alkaline solution under mild hydrothermal conditions (120 °C) within 24 h. The quantitative phase analyses of the TRM carried out by applying the Rietveld method showed the occurrence of a large amount of well-crystallized 11 Å Al-substituted tobermorites and an amorphous phase and a lower content of aragonite and calcite.

Autoři článku: Mcphersonsalisbury4898 (Massey Rich)