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The actin cytoskeleton is extremely dynamic and supports diverse cellular functions in many physiological and pathological processes, including tumorigenesis. However, the mechanisms that regulate the actin-related protein 2/3 (ARP2/3) complex and thereby promote actin polymerization and organization in cancer cells are not well-understood. We previously implicated the proline-rich 11 (PRR11) protein in lung cancer development. In this study, using immunofluorescence staining, actin polymerization assays, and siRNA-mediated gene silencing, we uncovered that cytoplasmic PRR11 is involved in F-actin polymerization and organization. We found that dysregulation of PRR11 expression results in F-actin rearrangement and nuclear instability in non-small cell lung cancer cells. Results from molecular mechanistic experiments indicated that PRR11 associates with and recruits the ARP2/3 complex, facilitates F-actin polymerization, and thereby disrupts the F-actin cytoskeleton, leading to abnormal nuclear lamina assembly and chromatin reorganization. Inhibition of the ARP2/3 complex activity abolished irregular F-actin polymerization, lamina assembly, and chromatin reorganization due to PRR11 overexpression. Notably, experiments with truncated PRR11 variants revealed that PRR11 regulates F-actin through different regions. We found that deletion of either the N or C terminus of PRR11 abrogates its effects on F-actin polymerization and nuclear instability and that deletion of amino acid residues 100–184 or 100–200 strongly induces an F-actin structure called the actin comet tail, not observed with WT PRR11. Our findings indicate that cytoplasmic PRR11 plays an essential role in regulating F-actin assembly and nuclear stability by recruiting the ARP2/3 complex in human non-small cell lung carcinoma cells.

Identifying highly efficient catalysts for direct CO2 hydrogenation to liquid hydrocarbons is crucial for CO2 utilization via chemical conversion using renewable resources, the so-called Power-to-Liquids. In this study, well-defined mesoporous carbon (MPC) of 6.9 nm pore size was synthesized as a support material for Fe oxycarbide nanoparticles, which serve as active sites for the CO2 hydrogenation reaction, combining reverse water-gas shift and Fischer-Tropsch reactions. The unique physicochemical properties of MPC favored the formation of an active carbidic Fe phase and the rapid diffusion of produced hydrocarbons which resulted in an enhanced CO2 conversion and long-chain hydrocarbon selectivity. As a result, the MPC supported Fe catalyst showed C5+ hydrocarbon selectivity of 44.5% with a CO2 conversion rate of 50.6% (300 °C, 2.5 MPa, H2/CO2 = 3).

A series of Zn modified hierarchical ZSM-5 catalysts with Si/Al ratios of 25 and 40, and Zn loading amounts of 0, 0.5, 1, and 2 wt% was designed to pursue a highly efficient catalyst with excellent catalytic activity and stability toward BTEX formation in the aromatization of light hydrocarbons. The Zn modified hierarchical ZSM-5 catalysts with intracrystalline mesopores were prepared by alkali treatment and Zn impregnation. The effects of the alkali treatment and Zn modification on the textural property, acidity, catalytic performance, and coke formation were investigated in detail via various characterization techniques. It was found that the catalytic stability of the alkali-treated catalysts notably improved. This can be mainly attributed to the fact that the alkali treatment of the pre-synthesized ZSM-5 generated a large amount of mesopores, which could alleviate the diffusion limitations. Moreover, the Zn modification remarkably improved the initial BTEX yield, which was due to the improved Lewis/Bronsted (L/B) ratio in the prepared catalysts. However, as the Zn loading amount increased from 0 to 2 wt%, the catalyst stability dramatically decreased, especially for the 2 wt% case. It seems that the balance between the Lewis and Bronsted acid sites (i.e., the suitable L/B ratio) is the key to obtaining both high BTEX yield and catalyst stability, and the optimum Zn loading amount is determined to be 0.5 wt% with an L/B ratio of around 1.

Three HZSM-5 zeolites with initial Si/Al ratios of 15, 25, and 40 were treated using an alkali solution to establish a hierarchical micropore-mesopore interconnected structure in alkali-treated zeolite samples Z15-AT, Z25-AT, and Z40-AT, respectively. The aim of the present work is to improve the catalytic stability in the aromatization of ethylene, a model compound representing the light hydrocarbons produced by the high-temperature Fischer‒Tropsch synthesis. By using characterization techniques, such as XRD, ICP, N2 adsorption/desorption, TEM, 27Al and 29Si MAS/NMR, NH3-TPD, Pyridine-IR, and TGA, we analyzed the textural property and acidity of the fresh catalysts, as well as the coke formation rate of the spent catalysts. The catalytic stability was shown to be successfully enhanced in the light hydrocarbon aromatization and the initial Si/Al ratio is a crucial factor for the mesopore formation and the catalytic performance. Among the prepared zeolite samples, the Z25-AT sample seemed to be the most suitable catalyst owing to its significant enhancement in the catalytic stability. The main reason for the improved stability by alkali treatment seems to be that the hierarchical pore structure facilitates the mass transfer and provides the additional space for carbon deposition as well, thus weakening the pore blocking and prolongs the lifetime of the catalyst.

The effect of the Fe/Co ratio on the catalytic performance of Fe–Co/alumina catalysts has been investigated in the production of high-calorific synthetic natural gas (SNG) from syngas. Fe–Co/alumina catalysts with different Fe/Co molar ratios were synthesized by the co-precipitation method and characterized using XRD, BET, H2-TPR, Raman, XAS, and XPS. At higher Fe/Co ratios (≥2), the calcined Fe–Co/alumina catalysts were mainly composed of α-Fe2O3 and CoFe2O4. The presence of Co improved the dispersion of iron oxides and the catalyst reducibility under H2 atmosphere. The Fe–Co/alumina catalysts partially formed FeCo alloys when they were reduced at 350 °C under H2. The formation of FeCo alloy destabilized the iron carbide phase and suppressed the carbon chain growth. These Fe–Co/alumina catalysts were efficient in producing high calorific SNG with a heating value of over 60 MJ/Nm3.

In recent years, significant attention has been paid to the CO2 mitigation via the power-to-liquids (PTL) and power-to-gas (PTG) processes because they can efficiently transform CO2 into high-value products such as liquid hydrocarbons and synthetic natural gas (SNG), and provide a promising solution for the storage of the intermittent renewable energy. Herein, we suggested a PTL process and a PTL/PTG process combined with the reverse-water-gas-shift (RWGS) and Co-based Fischer-Tropsch synthesis (FTS), which respectively produce liquid hydrocarbons only and the combination of liquid hydrocarbons and high-calorie SNG, based on the previous study regarding the PTL and PTL/PTG processes composed of Fe-based FTS. We conducted the process modelling and comparative techno-economic analysis to determine the key performance of the proposed PTL and PTL/PTG processes including the CO2 mitigation rate, energy efficiency, total product cost and CO2 mitigation cost. The proposed PTL and PTL/PTG processes can be regarded as feasible technical solutions to convert wasted CO2 into high-value liquid hydrocarbons and SNG. Additionally, the indirect PTL and PTL/PTG processes were helpful for improving the production of liquid hydrocarbons. Meanwhile, the direct PTL/PTG processes and indirect PTL processes favor the energy efficiency and CO2 mitigation.

The power-to-liquids (P2L) and power-to-gas (P2G) processes which utilize renewable power to convert carbon dioxide and water into value-added syncrude and synthetic natural gas have recently gained much attention as an efficient way for CO2 mitigation. Based on our previously proposed direct P2L and P2L/P2G hybrid processes in the absence of the reverse-water–gas-shift unit, in this work, we developed the indirect P2L and P2L/P2G hybrid processes combined with the reverse-water–gas-shift unit, which produce solely syncrude and the combination of syncrude and synthetic natural gas, respectively. A comparative study of the indirect and direct P2L and P2L/P2G hybrid processes via the process modelling and techno-economic analysis was implemented to quantitatively evaluate their process performance differences, and it was indicated that the indirect P2L and P2L/P2G hybrid processes were also able to be considered as suitable technologies for the transformation of CO2 into high-value hydrocarbons, and the indirect P2L/P2G hybrid process seemed to be more competitive than the indirect P2L process from both technical and economic aspects. Moreover, compared to the direct P2L and P2L/P2G hybrid processes, the indirect P2L and P2L/P2G hybrid processes produce more syncrude, however, they are less efficient in aspects of energy efficiency and net CO2 reduction.

Conceptual design for two options of carbon-dioxide-utilized gas-to-methanol process (CGTM) was implemented by using process simulation software Aspen Plus. The overall mass and energy stream results as well as the thermal and carbon efficiency were obtained from the developed process models. Before the following economic evaluation and sensitivity analysis, total capital investment (TCI) and total product cost (TPC) of both CGTM options were determined. Then, economic evaluation were conducted to assess the economic profitability of the base cases for both CGTM options, using the economic evaluation indicators such as net present value (NPV), internal rate of return (IRR), and discounted payback period (DPBP). Furthermore, sensitivity analysis as well as break-even analysis were also applied to investigate the economic performance of both CGTM options under different circumstances, by changing parameters such as methanol and NG prices, plant scale, and carbon tax. It was shown that the methanol price, CAPEX, and NG price are the most sensitive factors, and the two CGTM options were economically feasible in the plant scale range of 2500–5000 ton per day, according to the economic evaluation indicators NPV, IRR, and DPBP, and were more economically competitive in the case of higher plant scale and carbon tax.

Two process models for a carbon-dioxide-utilized gas-to-methanol (GTM) process (CGTM) that primarily produces methanol were developed using the process simulation software Aspen Plus. Both models comprised a reforming unit, a methanol synthesis unit and a recycling unit, with the feeding point of the fresh feed CO2 as the principal configurational difference. In the reforming unit, CO2/Steam–mixed reforming was performed to generate the targeted syngas in flexible compositions. Meanwhile, CO2 hydrogenation was conducted over a Cu-based catalysts in the methanol synthesis unit to directly produce the targeted product, methanol. After methanol synthesis, the unreacted syngas was recycled to the methanol synthesis and reforming units to enhance energy efficiency. The simulation results revealed that both CGTM options can favorably improve the energy efficiency and significantly reduce the total CO2 emissions, compared to a conventional GTM process. The energy efficiency was shown to be highly affected by the recycle ratio and a higher recycle ratio seemed to favorably improve CO2 conversion, enhance energy efficiency, and reduce CO2 emissions. However, the split ratio (recycle-to-reforming unit/total recycle) seems to have little effect on the energy efficiency, and the optimum recycle to the reforming unit was determined to be none.

This study proposed a novel chemical looping coupling system for coproducing syngas and hydrogen with in situ CO2 utilization. It integrates chemical looping combustion, chemical looping reforming, CO2-H2O co-splitting, hydrogen production and air oxidation using CH4 as fuel and iron oxide as oxygen carrier. In this process, syngas and H2 purification, in addition to CO2 capture and storage are no longer necessary. It not only produces high-purity hydrogen and syngas without pollutants and greenhouse gas emissions, but realizes the sufficient utilization of feed and oxygen carriers. A detailed thermodynamic analysis of the proposed chemical looping coupling process was conducted by Aspen Plus. The effects of key parameters, such as feed ratio, temperature, and pressure in each reactor on the process performance were investigated in terms of the utilization of CH4, the yield and purity of syngas and hydrogen, and the oxygen carrier coupling. In addition, the energy balance was analyzed for the coupling system with heat exchanger network. Based on the established process model, we concluded that the preferable feed ratios in combustion, reforming, co-splitting, steam and air reactors were 4, 1, 0.4, 1.1 and 1.5, respectively. The preferable temperatures in the five reactors mentioned above were 900, 900, 850, 500 and 500 °C in sequence, and the preferable pressure was 1 atm in each reactor. Under these conditions, high-purity hydrogen (100%) and syngas (99% and 93% purity) with ideal H2/CO ratio (~2) could be obtained. The energy efficiency and exergy efficiency of this coupling system reached up to 90.54% and 72.04%, respectively.

Aiming at achieving the large-scale CO2-equivalent reduction in the landfill industry, conceptual design of two sustainable landfill gas-to-methanol process options without the pre-treatment and methanol upgrading sections were implemented via using Aspen Plus simulator. In both proposed options, the optimum syngas ratio (H2/(2CO + 3CO2) = 1) is fulfilled by either supplying additional H2 (option 1) or pre-separating the surplus CO2 in LFG using membrane (option 2). A comparative techno-economic analysis was carried out to determine the energy efficiency and the CO2-equivalent reduction rate, as well as the net present value (NPV), the internal rate of return (IRR), and the discounted payback period (DPBP) of both proposed options. It is shown that both options 1 and 2 can be regarded as alternative processes for converting landfill gas to methanol, and option 1 is more energy efficient and eco-friendly, while, option 2 is more economically competitive. Moreover, a sensitivity analysis indicates that the CAPEX, the prices of methanol, CO2 allowance, and H2 are the most sensitive factors, and option 1 can be economically comparable with option 2 given that the H2 price can be lowered down to around 1000 $/Mt. This work provides two candidate process routes for efficient conversion of landfill gas to value-added methanol, which makes the landfill industry become more sustainable and profitable, especially in the event of a future high carbon tax and low H2 price.

Two process models for modular gas-to-liquids (GTL) process mainly producing Fischer–Tropsch (F–T) synthetic oils were developed by Aspen Plus software. Both models mainly comprised a reforming unit, an F–T synthesis unit, and a recycle unit, with the syngas generation and syngas ratio conditioning methods as the main difference. In the reforming unit, either steam reforming or CO 2 /Steam-mixed reforming was selected to generate the desired syngas. Co-based microchannel F–T synthesis was applied to convert the obtained syngas to synthetic oils. After F–T synthesis, a portion of the unreacted syngas was recycled to improve energy efficiency, and reduce CO 2 emissions. Technical and economic analyses were both employed to investigate the two modular GTL options. For the technical aspect, effects of recycling and splitting ratios on the performance of both options were investigated. Sensitivity analysis and break-even analysis were applied to the economic analysis. It was found that the increased energy efficiency and reduced CO 2 emissions could be achieved by recycling a portion of the unreacted syngas. Both options were economically viable at the plant scale of 2500 BPD, and were more competitive in the event of high carbon tax.

Aiming at achieving large-scale CO2 mitigation in the iron & steel industries via efficient utilization of the by-product gases such as the coke oven gas (COG) and Linz-Donawitz converter gas (LDG) in the iron & steel works, conceptual design of a LDG-to-methanol process (option 1) and two LDG/COG-to-methanol processes (options 2 and 3 without or with H2 purification, respectively) was implemented using the process simulator Aspen Plus. Both the process development and economic analysis for all the three proposed options were conducted to determine the technical performance via indicators such as the energy efficiency and CO2 reduction rate, and the profitability via indicators such as the total capital investment and the net methanol production cost. Meanwhile, six case studies under different recycle ratios (0.5–0.95) were conducted for each proposed option to investigate the effects of recycle ratio on the technical and economic performance. The techno-economic analysis results clearly show that all the three proposed options are highly efficient for CO2 mitigation via methanol production using the by-product gases LDG and COG. More specifically, options 1 and 3 seem to be more energy efficient and eco-friendly than option 2, in terms of energy efficiency and CO2 reduction rate. Whereas, options 2 and 3 seem to be more economically feasible than option 1, considering the net methanol production cost. From the aspects of both technical and economic performance, option 3 is considered as the most competitive process. This work provides candidate process routes for the iron & steel industries to become more sustainable and profitable, especially in the event of a high carbon tax and a low H2 price in the future.

Conceptual design of two options of carbon dioxide utilized gas-to-liquids process (CUGP), which mainly produces light olefins and Fischer–Tropsch (F–T) synthetic oils, has been implemented with the aid of Aspen Plus software. The mass and energy stream results as well as the process efficiencies and CO2 emissions of the proposed options were obtained from the developed models. The capital investment and the product cost estimations were conducted before the following economic analysis. Several indicators such as net present value (NPV), discounted payback period (DPBP) and internal rate of return (IRR) were calculated to evaluate the profitability of the two proposed options. In the economic analysis, sensitivity analysis as well as break-even analysis was carried out. In addition, effects of several sensitive factors such as the prices of synthetic oil, olefin and natural gas, capital investment, carbon tax and plant scale on the IRR of each option were analyzed in detail. It was found that the CUGP, regardless of option, was economically feasible at the plant scale of 40,000 BPD and was more competitive compared with conventional GTL processes, in case of high carbon tax.

Carbon dioxide reforming of methane on Ni–MgO–Al 2 O 3 catalysts has been investigated systematically at various Mg/Al ratios, focusing on catalytic activity and coke resistance. Ni catalysts supported on MgO–Al 2 O 3 were prepared by sol–gel method using citric acid as a gelling agent. The characterization of the catalyst was carried out by XRD, TEM, TPR, N 2 adsorption, H 2 chemisorption, O 2 titration, CO 2 -TPD and TGA. In the comparison with a catalyst prepared by coprecipitation method, it was found that the catalyst prepared by the sol–gel method showed higher coke resistance. In the variation of Mg/Al ratios, high coke resistance was obtained with increasing MgO loading, while high catalytic activity was observed with the catalysts of medium MgO/(MgO + Al 2 O 3 ) ratio (0.44–0.86), of which the superior catalytic activity is likely attributed to high specific surface area and well dispersed Ni particles.

The silk gland is an important organ in silkworm as it synthesizes silk proteins and is critical to spinning. The genomic DNA content of silk gland cells dramatically increases 200-400 thousand times for the larval life span through the process of endomitosis. Using in vitro culture, DNA synthesis was measured using BrdU labeling during the larval molt and intermolt periods. We found that the cell cycle of endomitosis was activated during the intermolt and was inhibited during the molt phase. The anterior silk gland, middle silk gland, and posterior silk gland cells asynchronously exit the endomitotic cycle after day 6 in 5th instar larvae, which correlated with the reduced expression of the cell cycle-related cdt1, pcna, cyclin E, cdk2 and cdk1 mRNAs in the wandering phase. Additional starvation had no effect on the initiation of silk gland DNA synthesis of the freshly ecdysed larvae.

Isobaric vapor–liquid equilibrium (VLE) data for acetic acid + water, acetic acid + n-propyl acetate, acetic acid + iso-butyl acetate, acetic acid + water + n-propyl acetate, acetic acid + water + iso-butyl acetate are measured at 101.33 kPa with a modified Rose still. The nonideal behavior in vapor phase caused by the association of acetic acid are corrected by the chemical theory and Hayden–O’Connell method, and analyzed by calculating the second virial coefficients and apparent fugacity coefficients. The VLE data for acetic acid + water, acetic acid + n-propyl acetate, and acetic acid + iso-butyl acetate are correlated through the NRTL and UNIQUAC models using the nonlinear least square method. The obtained NRTL model parameters are used to predict the ternary VLE data. The ternary predicted values obtained in this way agree well with the experimental values.