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The stability of combustion in the process of fire flooding requires not only a reasonable gas injection rate but also a matching exhaust rate. A reasonable injection-production balance system is very important. Based on the material balance of injection-production, the expression of injection-production ratio suitable for normal fire flooding production is established. The air injection rate of fire flooding combustion and oxygen consumption of formation pressurization is analyzed by this formula to calculate the gas production and liquid production in combustion. The reasonable injection and production parameters for the oilfield are calculated by using the oilfield parameters. It can be seen that the calculated value of injection-production ratio is consistent with the actual value, which shows that the injection-production ratio is reasonable and can guide the adjustment of production parameters in the oilfield.

The process of the fluid catalytic cracking (FCC) is accompanied by complex physical and chemical reactions and phase transition processes. For the FCC process–maximizing isoparaffin process (MIP), coupled simulation and optimization of flow reaction can meet the requirements for the design and operation of high efficiency, low energy consumption, low pollution, and low cost in the catalytic device. A combination of Eulerian–Eulerian model and 11-lump kinetic model is adopted to simulate the flow-reaction process of gas–solid two-phase of an industrial MIP riser reactor. A drag model based on the energy-minimization multiscale model established by Yang is incorporated into FLUENT through a user-defined function (UDF). The temperature distribution of the catalyst and the concentration of each product component at the outlet are in good agreement with the industrial measured data, which indicates that the established coupling model of flow reaction and drag model are reliable and effective. The two operating variables of the catalyst-to-oil ratio and catalyst inlet temperature are explored their effects on the flow-reaction process of FCC gas–solid two-phase. In the prelifting zone, the velocity of catalyst particles presents parabolic distribution. In the first reaction zone, the maximum velocity of catalyst particles is about 1/2 of the radius of the riser. In the second reaction zone, the maximum particle velocity of catalyst is located in the central region, with a slight increase in about 1/2 of the radius of the riser. The increase in catalyst-to-oil ratio leads to the decrease in the yield of diesel oil and the increase in yields of gasoline, liquefied petroleum gas, propylene, and dry gas. The changes in the catalyst inlet temperature affect the product distribution of the outlet component, which can provide an important guiding significance.

Electrical double layer capacitors (EDLCs) featuring low-cost and solution-processable electrode materials have attracted significant research interest for their green and economical applications in energy harvesting and storage devices. Here, we demonstrate a novel synthetic route for films of an underexplored 3-D hexagonal bismuth chalcohalide, Bi13S18I2, and investigate its potential as the active electrode material in EDLC-type supercapacitors. The synthetic procedure has been optimised and comprises the lowest annealing temperature (150 °C) and the shortest processing time (1 h) currently reported. When integrated in a symmetrical EDLC with an aqueous NaClO4 electrolyte, the Bi13S18I2-based device achieves a remarkable areal capacitance of 210.68 mF cm−2 with 99.7% capacitance retention after 5000 cycles. Both the Bi13S18I2 powder and thin-film electrodes have been characterized through XRD, XPS, Raman spectroscopy, and SEM. The superior stability, low-cost, and facile synthesis of Bi13S18I2 proves its promising potential for supercapacitor applications.

To meet the requirement of high molar extinction coefficient, broad absorption spectrum, and photo/thermal stability for sensitizers of quasi-solid-state dye-sensitized solar cells (Qs-DSSCs) with reduced film thickness, a novel D-A-π-A configuration organic sensitizer IQ22 was specifically designed, in which the conjugation bridge of cyclopentadithiophene (CPDT) unit was incorporated to widen the light response and enhance molar coefficients for increasing the short-circuit current density (JSC), and the octane chain on CPDT was targeted for suppressing the charge recombination and improving the open-circuit voltage (VOC). As a result, the Qs-DSSC based on IQ22 exhibits very promising conversion efficiency as high as 8.76%, with a JSC of 18.19 mA cm–2, a VOC of 715 mV, and a fill factor (FF) of 0.67 under AM 1.5 illumination (100 mW cm–2), standing out in the Qs-DSSCs utilizing metal-free organic sensitizers.

This paper reports on the synthesis, crystal structure and application of a novel hybrid bismuth-halide complex: (CN2SH5)3BiI6 (TBI) for supercapacitor applications, featuring merits including high areal capacitance, low cost, solution-processability and non-toxicity. Single crystal X-ray diffraction reveals that TBI crystallizes in the monoclinic system, with discrete [BiI6]3- octahedra as the inorganic motif. Utilizing TBI as the active supercapacitor electrode material with carbon cloth current collector and aqueous NaClO4 electrolyte, an electrode areal capacitance of 3.32 F/cm2 and a systemic specific capacitance of 1030 F/g was achieved when the device operates as an electric double-layer capacitor (EDLC). The supercapacitor device shows excellent capacitance retention even after 5,000 charge-discharge cycles. The powder XRD patterns, Raman spectroscopy and SEM images of TBI electrodes were compared before and after the cycling test to demonstrate the material stability and investigate the film morphology.

We report on the synthesis, crystal structures, optoelectronic properties and solar cell device studies of three novel organic-inorganic iodobismuthates -- [C3H4NS]3[Bi2I9] ([TH]3[Bi2I9]), [C3H4N2]3[Bi2I9] ([IM]3[Bi2I9]) and [C3H5N2S][BiI4] ([AT][BiI4]) as lead-free light harvesters. [TH]3[Bi2I9] and [IM]3[Bi2I9] show zero-dimensional structures, whereas a one-dimensional edge-sharing chain structure of BiI6-octahedra was observed in [AT][BiI4], with interchain short I…I contacts also giving rise to the possibility of three-dimensional charge transport ability. Accordingly, greater energy dispersion in the band structure of [AT][BiI4] can be observed, and less contribution from the organic moities at the conduction band minimum in [AT][BiI4] than [TH]3[Bi2I9] have been confirmed by density functional theory calculations. Moreover, bandgap values are redshiffted from 2.08 eV for [TH]3[Bi2I9] and 2.00 eV for [IM]3[Bi2I9] to 1.78 eV for [AT][BiI4], determined by UV-Vis reflectance spectroscopy. Power conversion efficiency of 0.47% has been achieved by using ([AT][BiI4]) as the light absorber in a hole-conductor-free, fully printable solar cell, with relatively good reproducibility. We also note the observation of a capacitance effect for the first time in a photovoltaic device with bismuth-based solar absorber, which may be related to the mesoporous carbon counter-electrode.

Recently, enormous research passion has been devoted to enhance the power conversion efficiency (PCE) of porphyrin sensitizers for dye-sensitized solar cells (DSSCs), but the major stumbling block is the absorption defect in the visible-light region. To address this challenge, high-performance DSSCs are reported based on a new donor-π-acceptor sensitizer FW-1, 7H-dibenzo[c,g]carbazole-substituted and fused zinc porphyrin, co-sensitized with a benzotriazole-containing dye (WS-5) in iodine and cobalt redox systems, and high PCEs of 10.21 and 10.42 %, respectively, were obtained. An unprecedented breakthrough was obtained by making one sensitizer suitable for several electrolyte systems because of its appropriate molecular orbitals and co-sensitizer.

Supercapacitors are well-known as promising energy storage devices capable of bridging the gap between conventional electrolytic capacitors and batteries to deliver both high power and energy densities for applications in electric vehicles and a smart energy grid. However, many reported instances of high-capacitance pseudocapacitors employ strong Faradaic reactions that hinder fast charge–discharge cycles and long-term stability, limiting their commercial viability. In this study, we utilise an economical and solution-processable procedure to fabricate a Cs3Bi2I9-based symmetric supercapacitor employing both electric double layer capacitance and pseudocapacitance with an aqueous NaClO4 electrolyte to deliver an outstanding device areal capacitance of 2.4 F cm−2 and specific capacitance of 280 F g−1. The Cs3Bi2I9 device achieves an excellent 88% capacitance retention after 5000 charge–discharge cycles, proving its long-term cycle stability and promise as a practical supercapacitor. We characterise the time-dependent charge storage mechanisms through cyclic voltammetry and electrochemical impedance spectroscopy to find that electrostatic charge accumulation predominates at high potentials (0.3–0.6 V) whereas weak, Faradaic charge adsorption and pore penetration bolster charge storage at lower potentials (0.0–0.2 V).