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1.
Sci Rep ; 14(1): 9959, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38693281

RESUMO

Steam-assisted gravity drainage (SAGD) is an efficient thermal recovery technique for oil sands and extra heavy oil exploitation. The development of steam chamber goes through multi-stage physical processes for SAGD production in a heavy oil reservoir with an interlayer. In this study, considering the situation that an interlayer is located directly above a pair of horizontal wells, we analyzed the whole process of steam chamber development. We divided the whole process into stages I-V, which are the first rising stage, the first lateral expansion stage, the second rising stage, the second lateral expansion stage and the confinement stage, respectively. Particularly, we further divided stage II into 2 periods and stage IV into 3 periods. These stages and periods can help us understand the development process of steam chamber dominated by an interlayer more profoundly. Based on the divided stages and periods, we established different models of SAGD production by assuming different geometric shapes of steam chamber in different stages and periods. Oval shape was assumed in stages I and III, and inverse triangle shape was hypothesized in stages II, IV and V. The formulas of the front distance of steam chamber and the oil production rate of SAGD were deduced from the established models for different development stages. At the end, we performed two example applications to SAGD production in heavy oil reservoirs with an interlayer. The real oil production rates were matched very well with the theoretical oil production rates calculated by the deduced formulas, which implies the multi-stage development model of steam chamber is of reliability and utility.

2.
ACS Omega ; 7(17): 15123-15131, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35572758

RESUMO

Silicon monoxide (SiO x ), as a promising anode for the next-generation high-power lithium-ion batteries, has some advantages such as higher lithium storage capacity (∼2400 mAh g-1), suitable working potential, and smaller volume variations during cycling compared with pure silicon. However, its disadvantages such as its inherent low conductivity and high cost impede its extensive applications. Herein, we have developed a low-cost and high-capacity SiO x /C@graphite (SCG) composite derived from oat husks by a simple argon/hydrogen reduction method. For further practical application, we also investigated the electrochemical performances of SiO x mixed with different ratios of graphite. As an advanced anode for lithium-ion batteries, the SCG-1 composite exhibits an excellent electrochemical performance in terms of lithium storage capacity (809.5 mAh g-1 at 0.5 A g-1 even after the 250th cycle) and high rate capability (479.7 mAh g-1 at 1 A g-1 after the 200th cycle). This work may pave the way for developing a low-cost silicon-based anode derived from biomass with a large reversible capacity and long cycle life in lithium-ion batteries.

3.
ACS Omega ; 5(27): 16440-16447, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32685807

RESUMO

Silicon suboxide (SiO x ) is one of the most promising anodes for the next-generation high-power lithium-ion batteries because of its higher lithium storage capacity than current commercial graphite, relatively smaller volume variations than pure silicon, and appropriate working potential. However, the high cost, poor cycling stability, and rate capability hampered its industrial applications due to its complex production process, volume changes during Li+ insertion/extraction, and low conductivity. Herein, a low-cost and high-capacity SiO x /C@graphite (SCG) hybrid was designed and synthesized by a facile one-pot carbonization/hydrogen reduction process of the rice husk and graphite. As an advanced anode for lithium-ion batteries, the SiO x /C@graphite hybrid delivers a high reversible capacity with significantly enhanced cycling stability (842 mAh g-1 after 300 cycles at 0.5 A g-1) and rate capability (562 mAh g-1 after 300 cycles at 1 A g-1). The great improvement in performances could be attributed to the positive synergistic effect of SiO x nanoparticles as lithium storage active materials, the in situ-formed carbon matrix network derived from biomass functioning as an efficient three-dimensional conductive network and spacer to improve the rate capability and buffer the volume changes, and graphite as a conductor to further improve the rate capabilities and cycling stability by increasing the conductivity. The low-cost and high-capacity SCG derived from rice husk synthesized by a facile, scalable synthetic method turns out to be a promising anode for the next-generation high-power lithium-ion batteries.

4.
Zhongguo Zhong Yao Za Zhi ; 45(23): 5738-5744, 2020 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-33496114

RESUMO

To investigate the effect of baicalin extracted from Qinbai Qingfei Concentrated Pills on the expressions of TGF-ß1, mmp2 and timp2 in mice with pulmonary fibrosis induced by bleomycin. The Biacore technique was used to detect the specific binding between Qinbai Qingfei Concentrated Pills and TGF-ß1, and the affinity components were enriched, regenerated and recovered by Biacore fishing. Then ultra-performance liquid chromatography and quadrupole time of flight mass spectrometry(UPLC-Q-TOF-MS) were used to determine whether the monomer was baicalin. Biacore was used to verify the affinity kinetics of baicalin, which was validated by pharmacodynamics in vivo. Totally 30 BALB/C mice were randomly divided into three groups: baicalin group, blank group and model group. The blank group was given sodium chloride injection(0.08 mL·kg~(-1)), while the model group and the baicalin group were injected with 4 mg·kg~(-1) bleomycin. The localization of TGF-ß1, mmp2 and timp2 protein in the cells and the mRNA expressions of TGF-ß1, mmp2 and timp2 were detected by RT-PCR 14 days later. The results of Biacore affinity analysis showed that the peak of binding response between Qinbai Qingfei Concentrated Pills and TGF-ß1 protein reached 1 524.0 RU, with specific binding. The affinity constant K_D of baicalin and TGF-ß1 was 1.620 06 µmol·L~(-1), which was determined by SPR kinetic analysis, suggesting a stable binding between baicalin and TGF-ß1, which verified the results of angulation. The results of immunohistochemistry showed that the deposition of cellulose in baicalin group was significantly less than that in model group, the mRNA expressions of TGF-ß1, mmp2 and timp2 were decreased in baicalin solution compared with the model group. Baicalin combined with TGF-ß1 could inhibit the expressions of mmp2 and timp2 and delay the progress of pulmonary fibrosis.


Assuntos
Fibrose Pulmonar , Fator de Crescimento Transformador beta1 , Animais , Flavonoides , Cinética , Camundongos , Camundongos Endogâmicos BALB C
5.
ACS Omega ; 4(14): 16016-16025, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31592125

RESUMO

Porous multicomponent Mn-Sn-Co oxide microspheres (MnSnO3-MC400 and MnSnO3-MC500) have been fabricated using CoSn(OH)6 nanocubes as templates via controlling pyrolysis of a CoSn(OH)6/Mn0.5Co0.5CO3 precursor at different temperatures in N2. During the pyrolysis process of CoSn(OH)6/Mn0.5Co0.5CO3 from 400 to 500 °C, the part of (Co,Mn)(Co,Mn)2O4 converts into MnCo2O4 accompanied with structural transformation. The MnSnO3-MC400 and MnSnO3-MC500 microspheres as secondary nanomaterials consist of MnSnO3, MnCo2O4, and (Co,Mn)(Co,Mn)2O4. Benefiting from the advantages of multicomponent synergy and porous secondary nanomaterials, the MnSnO3-MC400 and MnSnO3-MC500 microspheres as anodes exhibit the specific capacities of 1030 and 750 mA h g-1 until 1000 cycles at 1 A g-1 without an obvious capacity decay, respectively.

6.
Dalton Trans ; 48(25): 9205-9213, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31157342

RESUMO

Hierarchical porous MnCo2O4 yolk-shell microspheres have been synthesized via a facile chemical precipitation method with subsequent calcination treatment. The hierarchical porous MnCo2O4 yolk-shell microspheres as secondary nanomaterials can improve the effective contact area between the MnCo2O4 electrode and electrolyte, accommodate the volume variations during cycling, and shorten the Li+ diffusion path in the nanoparticles. Benefiting from their particular structure and interconnected pores, as anodes for lithium ion batteries, the hierarchical porous MnCo2O4 yolk-shell microspheres show high reversible lithium storage capacity, excellent cycling performance and enhanced rate capability. More importantly, they also exhibit long-life and high-rate lithium storage as high as 691.3 mA h g-1 after 500 cycles even at 1 C.

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